TW593748B - Method of obtaining protective coatings on the surface of chemically active materials - Google Patents

Abstract

The invention is concerned with a method of obtaining protective coatings on the surface of chemically active materials comprising a mixture of a chemically active metal and a fusible stable element. The method is characterized by comprising the steps of: providing at least one chemically active metal A; providing at least one fusible stable element B; mixing metal A and element B to form a mixture; treating said mixture at its surface with a liquid agent L, which is capable of dissolving metal A but not capable of dissolving element B, at a temperature which is higher than the melting point of element B thereby creating a coating consisting essentially of element B at the surface of said mixture; ceasing treatment when the desired thickness of the coating has been achieved; removing the liquid agent and cleaning and drying the mixture.

Description

593748 Α7 Β7 V. Description of the invention (1) Scope of the invention ## Η 月 is related to the preparation of a protective coating on the surface of a chemically active material ®% ′ The chemically active material includes a mixture of chemically active metals and fusible stabilizers. A 15-point metal materials are prone to erosion and must be prevented from coming from the stomach. This is particularly important in the case of active metals, which are quickly destroyed by short-term contact with the general environment. Overcome the problems of lithium, sodium, potassium, thallium, planer, magnesium, calcium, thorium, barium, radium, lanthanum, thorium, bait '铕', 纟, uranium, thorium, and several other metals, such as the high chemical activity of thorium ' Almost all in its processing and use phase. Whether the material is completely isolated from the environment by a coating or a sealed enclosure, or by mixing the material with another specially selected ingredient, partially reducing the metal's activity as a protective metal from the harmful effects of the environment and moisture Methods. The choice of the protection method depends on the requirements of the intended use phase of the material. The methods that can be used to deposit the protective coating from the vapor or liquid phase, such as physical or chemical deposition, sputtering, sputtering, plating, Glazing, oxidation, nitriding, etc. cannot be applied to active metals because of their high chemical reactivity. This is why there are two ways to protect the material environment when using active metals now: in sealed enclosures such as metal containers or glass vials and as a mixture of active metals and other substances. The first method is reliable in the storage and transportation of active metals, but requires special tools to open the casing, so it is not possible to provide the metal in small quantities. The second method is more convenient to handle the material during the use phase, but if the Chinese national standard (CNS) Α4 specification (210 × 297 mm) is applied to the paper size, I -------- install-- (please first Read the notes on the back and fill in this page) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs-4-593748 A7 B7 V. Description of the invention (2 The main demand for the source of active metals has become the method of releasing this metal. This method also has serious disadvantages when it is controlled. Therefore, in the alkali metal distribution reagent [US Patent No. 3579459 granted to Tirapota, Ribicin in 1971] or inspiratory evaporative barium As a result of the reaction in the agent, the vapor of the active metal A is generated, and the reaction is carried out in a powder form. AX + Me where AX is an inorganic compound (such as chromate or dichromate) or an intermetallic compound of metal A (such as AhBa), Me A reducing agent, A is the target of vapor. The disadvantages of this type of vapor source are the hygroscopicity of AX, vaporization during V '.', The exothermic characteristics of the reaction, and the carcinogenicity of chromium compounds. Metal vapor, it is recommended to make Thermal decomposition of the intermetallic compound (Read Notes on the back and then fill the page)

At

MeX +

AB B +

Printed by the Consumer Cooperative of the Intellectual Property Office of the Ministry of Economic Affairs, where AB is an intermetallic compound powder or a melt of the composition AB, and B is the second component. The advantage of this specified source is that it can accurately control the evaporation flow rate by changing the time and pyrolysis temperature [U.S. Pat. No. 3945949 of Van Wert and France in 1976; U.S. Pat. No. 4195 89 of Hailier in 1980 number 1]. However, the source of the specified pattern cannot be widely spread because of the high chemical activity of the intermetallic compound AB, especially in the powder form. Another type of method, but also by the precipitation of active metals, is carried out in many steps of organic synthesis reactions, which can be expressed in the general formula as the paper size applicable to the Chinese National Standard (CNS) A4 specification (2) 0X297 mm) -5- 593748 A7 _______B7_ V. Description of the Invention (3)

AY + R -► AR + Y or

R AsolV AR wherein AY is a compound of active metals a and Y, R is an organic substance, and solv is a liquid ammonia or a specific solution of tetrahydrofuran type. The typical problem in this article is the separation of most of the reaction products and the removal of solvents. The concern is that this reagent has a high explosion hazard and flammability. The object of the present invention is a method for preparing a protective coating on the surface of a chemically active material. The chemically active material includes a mixture of a chemically active metal and a fusible stabilizer, and provides a useful metallic black gas in a more effective way by conventional methods. source. Another object of the present invention is to provide chemically active materials, particularly suitable for use as a source of metal vapor, to overcome the disadvantages of the aforementioned techniques. In one aspect of the present invention, a method for preparing a protective coating on a surface of a chemically active material includes providing a mixture of a chemically active metal and a fusible stabilizer element, which is characterized by including the following steps:-providing at least one chemically active metal A-Provide at least one meltable stabilizing element B-Mix metal A and element B to form a mixture-Use liquid reagent L, which can dissolve metal a but cannot dissolve element B, at a temperature higher than the melting point of element B The surface of the mixture is treated at the same time, so that the surface of the mixture is essentially produced by element B. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 × 297 mm) (Please read the precautions on the back before filling this page ), Install ·

1T Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs-6-Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 593748 A7 ___ B7 V. Description of the Invention (4) Coating-When the coating reaches the desired thickness Discontinue treatment-decanting the liquid reagent and-decanting and drying the mixture.

The essence of the method according to the present invention is a mixture of active metal A and fusible stabilizer B with a liquid reagent L, which will dissolve the chemically active metal A but will not react with other ingredients of the material. As a result, metal A can be extracted from the mixture, so that an excessive amount of stabilizer element B is generated on the surface of the material. During the process, this excess stabilizer B will form a continuous liquid film (refer to Figure 3). The film isolates the material from direct contact with the liquid reagent L. After the treatment is terminated, a stabilizing film or coating consisting essentially of element B will be made on the surface of the material. The stabilizing film or coating will protect the material, especially the active metal A from the environment or other effects. . Although the coating material is always obtained from the outside in the prior art method for producing a protective coating, the method according to the present invention is treated with the target internal material source to form the protective coating. With regard to the method according to the invention, it is important that the treatment temperature is higher than the melting point (T f) of the element B. If the method is performed below the melting point of element b, the inner layer of the B atom, formed by this treatment, will be infiltrated by the liquid reagent B, so the corrosion of the mixture AB will continue to occur in the material until completely break down. However, 'If the temperature T > Tf (B) of this method, because this structure of the structure applies Chinese National Standard (CNS) A4 specifications (210X 297 mm)'-C Please read the precautions on the back before filling this page j

593748 A7 B7 V. Description of the invention (5) (Please read the precautions on the back before filling out this page} Changes will make the inner layer B dense. At first, the core of the molten material B appears in the entire inner layer, and then These cores will grow into a plurality of islands, and the islands formed by the molten material of B gradually grow and form new islands, and so on (refer to Figure 4) until all the islands merge into a continuous liquid film of component B. From then on In the method, the extraction of metal A is transformed into a diffusion distribution and the growth of the thin film B becomes controllable. The present invention first discloses a method capable of generating a protective coating on an intermetallic compound containing the most positively charged metal. Therefore, Metal A may be selected from alkali metals, alkaline earth metals, rare earth metals, and radioactive elements. Specifically, metal A may be selected from lithium, sodium, potassium, fine, absolute, magnesium, calcium, thallium, barium, radium, lanthanum, thallium, Bait, thorium, yttrium, uranium, thorium, and thorium. Element B may be selected from Group III, IV, V, and / or νΓ elements of the periodic table and their binary and ternary combinations with each other. Specifically, element B may Selected from gallium, indium and / or tin and their binary And ternary combination. · 丨 The protective shell composition printed by the employee's consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs is selected according to the target material. Because the activation temperature of the material is actually determined by the melting temperature of the B-coat, Therefore, in order to obtain the activation temperature widely used in many applications, different elements B or their combinations can be used. Therefore, the conventional organic synthesis application uses a gallium coating with a melting temperature of about 30 ° C, and a vacuum coating is recommended to use a tin coating For example, when generating an alkali metal source, lead coating is most suitable for operation in acidic media, etc. The following Table 1 provides a number of metal materials with a fixed solid-to-liquid temperature. The paper dimensions apply to Chinese national standards (CMS) A4 specification (210X297 mm) -8-593748 Μ B7 V. Description of the invention (6) Protective coating shell material,% recorded -14% indium gallium-8.4% tin gallium indium-21.5% Μ indium -50% tin-tin-43% bismuth-indium-tin-26% selenium-tin will lead lead melting temperature, C 15.3 20.5 29.8 72.7 120 139 156 183 221 232 271.3 327.5 In these examples, if the binary alloy is used to The most suitable material for the protective shell, for example, has a eutectic composition ^ (refer to Figure 7), a ternary mixture consisting of A-B! _ B2 should be synthesized so that the fine particles have a concentration such as the straight line a-, that is, the composition and The ratio between B2 is equal. The liquid reagent L may be selected from (a) a substance having a higher boiling point and a lower melting point than the melting point of element B, (b) a mixture of substances according to (a), and (c) according to (A) A substance or a mixture thereof (b) A solution dissolved in a solvent, the solvent is neutral to metal A and element B, that is, the liquid reagent L should conform to mp (L) < Tf (B) < bp (L) where mp (L) is the melting point of substance L, and bp (L) is the boiling point of substance L. The liquid reagent L is preferably selected from the group consisting of a CH-acid, an aliphatic alcohol, a polyhydric alcohol, a higher carboxylic acid, a condensed aromatic hydrocarbon and / or a macrocyclic polyether, a mixture thereof, and a solution. These substances can be divided into two groups, whether or not they are produced during the growth process of the end-view film. The paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) (please read the precautions on the back before filling this page).

-、 1T Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 593748 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of the invention (7) It depends on the angry hydrogen. The first group is composed of several kinds of organic compounds to replace the reaction with A. RH (/) + AB (s) RA (〇 + B (/) -f 1/2 H2 (g) 5 where 1, s and g is a symbol representing liquid, solid, and gaseous states. In addition to toxic substances, these substances are, for example, some high-boiling olefins RH (triphenylmethane, etc.), high-boiling ethers R-OR 'and esters (II Ethylene glycol, malonate, etc.), higher aldehydes R-CHO and ketones R-CO-R '(tolualdehyde, 2-heptanone, etc.), higher aliphatic and polyhydric alcohols R -OH (hexadecanol, propylene glycol, ethylene glycol, glycerol, sorbitol, xylitol, etc.), higher carboxylic acids r_COOH (stearic acid, palmitic acid, oleic acid, etc.) And other substances, their mixtures and their solutions in liquid diluent D, which is inactive to the AB system. Liquid ammonia, tetrahydrofuran and other ethers (anisole, diphenyl ether, etc.), aromatic Hydrocarbons (benzoin, xylene, etc.), alkanes (heptane, hexane, tartar oil, etc.) are examples of such diluents. Reactions of metals A with addition reactions The second group of extractants LL + AB (s) AL (/) + B (0 including condensed aromatic hydrocarbons (naphthalene, anthracene, etc.), macrocyclic polyethers ([18] -crown [6] ether 'Etc.), its mixture and the solution dissolved in the above-mentioned diluent D. Termination of the treatment with liquid reagent L is preferred to reduce the temperature to the melting of element B (please read the precautions on the back before filling this page). Order f This paper size is applicable to China National Standard (CMS) A4 specification (210X 297 mm) -10- 593748 A7 B7 5. The invention is completed under (8) points. The thickness of the coating can be 1 micron or more Large, preferably 10 microns or more (please read the notes on the back before filling this page) Large. The thickness of the coating can be controlled by adjusting the reaction period and / or processing time with the liquid reagent L. There are four types Possible methods can affect the dissolution of metal A, and then the thickness of coating B: change the temperature of the method, change the processing time, replace the liquid reagent L, and change the water flow conditions near the surface of the mixture of A and B. Temperature and extraction time Enables control of growth coating thickness: higher temperature and processing time Longer, the thicker the B-coat. Change from a liquid reagent L to another liquid reagent, or dilute the liquid reagent L with a neutral diluent D. The dilution D will not react with the ingredients of the material AB, and it will also affect Formation kinetics and growth of thin film B. In order to improve the uniformity of the coating, convection of the liquid reagent L is generated. The Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs prints the liquid reagent L in the case of a large surface mixture AB liquid flow Flow around this surface (refer to Figure 5). In the case where AB is a small particle, these particles are, for example, moving in the non-mobile medium L under the influence of gravity (see Figure 6). When the target thickness of the coating is reached, the procedure is stopped. Based on this, it is sufficient to reduce the temperature of the system AB-L to T < Tf (B). The liquid thin film B then solidifies and diffusion of A atoms via the solid continuous B layer becomes impossible. The mixture of metal A and element B is preferably immersed in liquid reagent L. The size of the paper is applicable to Chinese national standard (CNS) A4 specification (210X 297 mm) -11-593748 A7 B7 V. Description of the invention (9) 〇 (Please (Please read the notes on the back before filling this page) The mixture of metal A and element B can be formed into the desired shape before being treated with liquid reagent L. However, it is important to understand that the shape of the mixture of metal A and element B can also cause slight changes during treatment with liquid reagent L. The mixture of metal A and element B is preferably formed into a substantially spherical shape before being treated with the liquid reagent L. In this case, the substantially spherical mixture is dropped into the liquid reagent L bath. Furthermore, the mixture of metal A and element B can be formed into a cylindrical or plate shape before being treated with the liquid reagent L. The method of coating AB small particles with an average linear size of ~ 1.0 to ~ 5.0 mm can preferably be performed in two variables:

-Make the melt of AB into the liquid reagent L or-throw any solid or granulated AB solid particles into the liquid reagent L, and the upper layer of the liquid reagent L is heated to a temperature of T > Tf (B) In the first case, printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the melt AB was pressed by a particle collector through a capillary tube passing through an opening to a simple test tube, and a liquid reagent L was used (refer to FIG. 8). The droplets are coagulated in liquid reagent L, and then coated with coating B while moving downward. The molten droplets of AB contain a large amount of stored thermal energy to heat the upper portion of the bath to an undesired temperature T > Tf (B). However, the lower layer of the liquid bath L should still be maintained at a temperature level of T < Tf (B).

In the second case, the solid particles of AB were thrown into the liquid reagent containing L. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) -12- 593748 A7 ____B7 V. Description of the invention (10) (please Read the precautions on the back before filling this page) in the vertical extension bath (refer to Figure 6). The upper part of the bath is heated to T> Tf (B), and the lower part has a temperature T < Tf (B). The particles cover the liquid shell B while sinking in the hot layer, and then the shell solidifies in the cooling layer L below. The thickness of the coating is controlled by two parameters. The length of the hot part is Ah = h! -H. The temperature in this part is T !. The processing area is set so that the formation of the liquid film B is fixed at the time of visual observation and the particles have a shiny metal surface. The first test of the quality of the coating was to expose the coated particles to water at a temperature T < Tf (B). The disappearance of gloss during exposure indicates the continuity of the coating. After surface passivation, the product (large ingot or small block) is thoroughly rinsed with a suitable solvent to remove liquid reagent L, dried, and then used for each application. Other main features and advantages of the present invention: • High productivity: Generally it takes only a few seconds to form the protective coating. 0 Printed by the R Industrial Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. • Universality: The film formation method does not need to depend on the surface size or Depending on the shape. This method can be used for a wide range of products, the nature of the active ingredients, the number of these ingredients, and their concentrations are different for each product. In particular, this method first revealed the ability to produce protective coatings on materials containing alkali metals and alkaline earth metals. • Simple technology: This method does not require complicated equipment, and is performed at low temperatures, and can be performed using inexpensive, commercially available reagents. • Controllability of the method: The thin film growth method can be controlled with only two parameters-processing time and the temperature of the liquid reagent L. This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) -13- 593748 A7 B7 V. Description of the invention (11) • No relation to the initial surface state ... Partial removal during processing with liquid reagent 3 The material is overlaid and partially reconstructed, but the surface does not need to be prepared in advance. This is extremely important for the chemical activity of the material. In another aspect of the present invention, a chemically active material with a protective coating is prepared on the surface by the method of the present invention described above. The novel material according to the present invention represents an intermetallic compound on the free surface of a film of stabilizing element B. Materials according to the invention, for example, do not need to be stored in a vacuum or a protective gas. If the material according to the invention is heated, the vapor of the chemically active metal A can be freely arranged in a highly controlled manner. The evaporation temperature depends on the composition of the material. For example, in the case of a material including sodium, potassium, and / or planing as metal A, the evaporation temperature may be between 400 ° C and 700 ° C. Coated Pre-Metal Precursors and Their Advantages, 1976, Volume 47, '79 -82; 1996, Volume 47, 463 to 466; Vacuum, Volume 55, 101 to 1999 Page 107 and September 2000, revealed in the paper "Intermetallic Precursors" by Contenov and Steiner at the 2nd International Inorganic Materials Symposium held in Santa Barna, USA. However, Neither of these publications disclose the method of making these intermetallic precursors. The material according to the present invention combines the two methods of the prior art to solve the problem of protection of active materials, in other words, the use of a shell and the use of a mixture of a plurality of ingredients enables elimination of the disadvantages of its respective methods and the use of the advantages of each method . The structure of the coated particles according to the present invention is shown in Figure 1. The chemical paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X 297 mm) ^^ installed-(Please read the note on the back first (Fill in this matter again)

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs of the 1T-14-593748 A7 __ B7 V. Description of the invention (12) (Please read the notes on the back before filling this page) Active Intermetallic Compound Core A η B m (after The text indicates "AB"), in which A is an active metal and is enclosed in a fusible stabilizer element b. Under normal conditions, the solid cover layer B will not be penetrated by water, air and any other substances. For A, element B is chemically stable. These particles can do any work that works with Element B without any security measures. If the temperature rises to T > (B), where Tf (B) is the melting point of element B, the particles can be activated. If the core of the particle is equal to the composition c ^ Cr (refer to FIG. 2), then the shell is transformed into a semi-permeable membrane having a composition Cl, and the atoms of A are passed to the surface of the particle. In this example, the microparticle is a controllable source of metal A (Figure lb), which can be used as an alkali metal distribution reagent or evaporative getter, or as a pure europium atom A supply source for different reagents R, etc. . If the core has the composition C! ≪ c < C4 (refer to Figure 2), then when T> Tf (B), the shell B will react with the core as follows

Cn + B-^ Cn i + Cn-2 + ·., Printed by the Consumer Cooperatives of the Intellectual Property Office of the Ministry of Economy where n = 2, 3 or 4. As a result, the protective film distribution reagent and the highly active distribution layer, which help the main active core C%, will appear on the surface of the particles. This type of material is an excellent chemical absorbent and can be used as a non-evaporable getter in a closed unit or a gas purification filter. In another aspect of the present invention, the chemically active material according to the present invention is used as a vapor source, as a chemical absorbent, and in the form of a catalyst or in the form of a component of a produced product as an active metal in chemical synthesis. Source, and / or this paper size applies Chinese National Standard (CNS) A4 specification (210X 297 mm) 593748 A7 B7 V. Description of the invention (13) Used to manufacture specific alloys, sublimation pumps and / or particle accelerators. (Please read the precautions on the back before filling out this page} The chemically active material is preferably used for the production of light-emitting devices (such as photovoltaic cells, optical amplifiers, photoconductive camera tubes, image converters), and organic light-emitting diodes, etc. The chemically active material can also be used as a vacuum sealing device, such as in solar cells, electronic tubes such as CRT, X-rays, halogen lamps, Dour bottles, vacuum insulation panels and tubes, field emission displays, etc. Chemical absorbents (such as evaporative and non-evaporable getters). Furthermore, the chemically active material can be used as a chemical absorbent for gas purification, such as evaporative properties in plasma displays, gas filters, etc. And non-evaporable getter. The chemically active material can also be used for other purposes, such as as a specific alloy (using elements such as samarium, yttrium, sodium, lithium, etc.), used in sublimation pumps, used in particle accelerators , And used in more possible applications. Now the present invention will be described with reference to the drawings and the following preferred embodiments, but it should not be considered as a limitation of the scope of the present invention: Brief description of the printed diagram of the employee's consumer cooperative of the Ministry of Intellectual Property Bureau Figure 1: Shows the structure of the coated particles according to the present invention, where (a): shows the particles when T < Tf (B), where la represents a solid shell B, 2a represents an intermetallic compound core; (b): a specific example when T > Tf (B) is displayed, where lb represents a liquid shell with a composition of Cl (refer to FIG. 2), and 2b represents a The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) -16- 593748 A7, _B7_ V. Description of the invention (14) Forms the core of c = C !; (Please read the notes on the back before filling in this (Page) (c): Another specific example of microparticles showing T > Tf (B), where lc represents a dispersion layer constituting ChCh ..., 2c represents a core having a composition C! ≪ c < C4. Two examples of particle behavior depending on the core composition are shown below. If the core has a composition cs C2 (Figure 2), then T > Tf (B), the core will partially melt with the formation of a Cl liquid shell (Figure 2) ), And used as a semi-permeable membrane of metal A, to make A atoms from AB nucleus Passed to the outer surface of the shell Cl. The atom A can evaporate from the surface of the shell Cl, such as a source of alkali metal vapor or evaporable getter, or enter the corresponding liquid medium, which will consume the active metal A, As occurs in organic synthesis reactions. If the core has the composition Cl < c ^ C4 (Figure 2), then when the microparticle system is heated to T > Tf (B), the shell B will be dispersed with the surface of the sponge The core reaction generated on layers C! + C2 + ... (based on experience) the chemical activity of this dispersed layer is higher than that of pure metal A. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. This material is a superior & chemical absorbent used in the sealing of vacuum applications and for the production of pure gases, such as in filter bodies. This material has a low activation temperature Ta ^ Tf (B) and operates at room temperature, which is superior to standard non-evaporable absorbents (NEGs) in this respect. Brother 2: Figure 2 shows the generalized phase diagram of system A_B, where A_active metal, B-fusible stable component; CP, Ci, C2, ...-metal compounds; Cl-liquid phase composition, the composition It is in balance with crystalline Cl at temperature Td. The paper size applies Chinese National Standard (CNS) Λ4 specification (210X29 * 7 mm) -17- 593748 A7 B7 V. Description of the invention (15) State; in the concentration range C2 to A : _ Indicates the phase boundary when the A-based alkali metal is used; ..... indicates the phase boundary when the A-type alkaline earth metal is used. Figure 2 illustrates, by way of an exemplary binary system, how to choose the particulate materials needed to achieve different applications. In order to be suitable as a controlled vapor A generator and also include an evaporative getter, or as a controlled metal A source in a chemical reaction, the active particle core should have c = C !. If the temperature Td > Tf (Ci), where Tf (C!) Is the melting temperature of the compound ◦, metal A is passed through the liquid casing C1 under static-like conditions, that is, at a fixed rate. Intermetallic compounds used as non-evaporable getters having a high concentration of active metal gens, such as C2, C3, ..., etc., will be used as the core material. These compounds will form a thermodynamically unstable combination with the shell B, and will react when heated to T > Tf (B), and then the protective shell will disintegrate. Figure 3: Figure 3 illustrates the initial stage of treatment with liquid reagent L, where AB-metal A and intermetallic compound of element B, L-liquid reagent L, 0-A atom, ·-B atom, 3 1-B intermediate Layer 3 shows the starting mechanism of the B intermediate layer 31 at the interface between the solid AB and the liquid L. The sea-like structure of the intermediate layer B cannot prevent the material from eroding at a temperature T < Tf (B), but increasing the temperature to T > Tf (B) will cause structural changes, leading to a continuous liquid outside The appearance of shell B. This paper size applies to China National Standard (CNS) A4 (210X297 mm) (Please read the notes on the back before filling out this page) C. Order the Yinxian-18- 593748 A7 B7 V. Description of the invention (16) Figure 4: (Please read the notes on the back before filling this page) Figure 4 illustrates the main stages of the film formation process: (a): Show the initial stage (as shown in Figure 3) The state is the same), the atom 41 of metal A is dissolved in the liquid reagent L; (b): the sponge-like intermediate layer has the appearance of the island 42 of the molten material B; (c): the growth phase 42 of the island structure; (d) ): Continuous film 43 of melt B and conversion to diffusion extraction; Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs (e): Temperature reduction and formation of B solid protective coating 43. The different stages of the protective coating formation process begin with the formation of melt B (b), its growth (c) and the islands 42 combined into a continuous liquid film 43 (d) of component B until the temperature drops to T < Tf (B) is cured (e). The most important moment in the whole process is about the state (d), after which the temperature of the system AB-L can be reduced to stop the extraction of A-metal, or it can be maintained to further increase the thickness of the coating. Early cooling of the system, for example, from state (c), is premature and causes surface defects, in other words ‘the enclosure will have open (unprotected) areas. Figure 5: Figure 5 shows an example of passivation of the ingot, where 51 is a container including an ingot of the AB mixture, 52 is a glass test tube, 5 3 is the liquid flow of the liquid reagent L, and 54 is the method used in this method. Formed element B coating. This figure shows how the plane of the ingot AB is processed with the liquid reagent L. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X 297 mm) -19- 593748 A7 B7 V. Description of the invention (17) Principles for protection Sexual coating B. A cylindrical container 51 containing an ingot of the mixture AB was inserted into a glass test tube 52 having an opening for discharging the liquid reagent L in the lower portion. A liquid reagent L 53 is filled over the open surface of the ingot, heated to T > Tf (B), the surface is washed and the solution product is taken down along the outer wall. When a bright pure film 54 appears on the surface of the ingot, the temperature of the extraction solution 53 is lowered to T > Tf (B) and the feed is stopped. Thoroughly rinse the surface of the ingot and the entire container with a neutral solvent. The solvent will remove the remaining liquid reagent L. The container was then placed in a water tank containing distilled water to test the continuity of the coating. Finally, the water was washed off with acetone or alcohol. The product was blown and dried under vacuum. Fig. 6: Fig. 6 shows a microparticle coating, in which (a) shows a distribution device including a test tube 61, a hopper 62, and a ratchet gear 63; (b) shows a device for passivation, which includes a liquid reagent The bath liquid 64, the liquid bridge 65, the cylindrical tube 66, and the handle 67 of L; and (c) the temperature curve of the liquid bath is demonstrated; (d) is a schematic diagram of the hopper 62 and the ratchet gear 63 along the straight line NN in (a). Figure 6 reveals one of the ways to understand the solid AB particle (block or sphere) coating process. The main parts of the device are: the distribution device (a). The purpose of this device is to make the separated AB particles roll down one by one without the paper size applying the Chinese National Standard (CNS) A4 specification (210X 297 mm) I- -------- Install-(Please read the precautions on the back before filling this page)

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs -20-593748 A7 B7 V. Description of the invention (18) After the appearance of the e-liquid shell b appears in the bath liquid 64; containing the liquid I3 '§ formula In the bath 64 of the agent L, the formation and solidification of the liquid shell will occur in the bath 64; when the final product is concentrated, the discharge string 66 can be removed as quickly as possible without interrupting the process. The purpose of the hopper 62 is the same. The hopper 62 was charged and the particles dropped from the test tube 61 were carried out under flowing argon. The particles can enter the bath 64 one by one by adjusting the appropriate tilt angle α and the rotation frequency of the ratchet gear 63. The particles are covered in the heating zone (h-hO, the shell is solidified in the cooling zone (h0-h2) ', and then the coated particles will fall into the cylindrical tube 66 along the liquid bridge 65, and the handle 67 will be used. It helps to remove the coated particles regularly. Visually check the state of the particle surface during the movement of the particles through the heating zone and test the coating continuity of the obtained product. Set the heating zone to the minimum length. The diffusion process depends on the change, that is, the control range. Compared to the particle coating method starting from the melt, the specific method has less stringent requirements for the volatility of the liquid reagent L. Figure 7: Figure 7 Shows the concentration triangle relationship of the A-Βι-B2 system, in which the A series of active metals and B2 smeltable elements, and the Ce system 1-B2 binary system are co-melted; the shadow area along the line A-ce is based on this The preferred composition area of the active core of the invented particle. The range of the potential composition of the protective shell can be essentially adapted to the Chinese National Standard (CNS) A4 specification (210X297 mm) by the size of Aberdeen paper. I ----- ---_ Install II (please first Read the notes on the back and fill in this page) Order printed by the Intellectual Property Bureau's Consumer Cooperatives of the Ministry of Economic Affairs-21-593748 A7 B7 V. Description of the invention (19) (Please read the notes on the back before filling this page) Defining element B The binary or meta-eutectic composition of the composition is expanded. This extension is not only about the melting temperature of the protective shell, but also its chemical properties. The A-Bι-B2 ternary system in Figure 7 provides how to choose the active core of the particle Opportunity to make up the relevant shell material. The ratio of ingredients Bl and B2 in the following should preferably be the same as those used in the shell eutectic Ce. Figure 8: Figure 8 shows the process used to produce coated particles Device, in which 8 丨 series ingot AB, 82 series melting zone, 83 series metal wire, 84 series capillary glass film, 85 series flight tube, 86 series exhaust pipe, 87 series frosted conical joint, 88 indicates The vapor of volatile metal A, 89 is the melt of mixture AB, 810 is the melt droplet of mixture AB, 811 is the bath containing liquid reagent L, and 8 1 2 is the high-temperature furnace. Employee Cooperative of Intellectual Property Bureau, Ministry of Economic Affairs Printed directly from the 8th The device for obtaining coated particles from the molten material shown in the figure is composed of three parts: a melting zone 82, a flight tube 85 containing an exhaust pipe 86, and a glass bath connected to the flight tube 85 by means of a conical frosted joint 87 811. The bath 811 is filled with a liquid reagent L, which has an extremely low vapor pressure at room temperature. The melting zone 82 is divided into two parts by a glass film 84, and a capillary tube is formed in the center of the melting zone 82. A metal wire 83 is placed in the capillary tube. The operation sequence of the device is as follows. The ingot 81 is placed in the melting zone 82, and the gas flow from the exhaust pipe 86 flows in the reverse direction. Then seal the area above the area μ, as shown in detail in FIG. 9. From the above, the high-temperature furnace 8 1 2 is moved to the melting zone 8 2, and the aggregate is melted during continuous extraction. The size of the cast paper is in accordance with Chinese National Standard (CNS) A4 specification (210X297 mm) -22-593748 Employees' Cooperative Cooperative Association Printing A7 B7 of the Ministry of Economy Intellectual Property Bureau 5. Description of the invention (20) The block will melt, and due to the melt Under the action of the hydraulic pressure and the vapor pressure of the metal A, the melt will be slowly pushed away through the capillary opening. As the melt flows, the temperature of the high-temperature furnace will gradually increase to maintain a constant lowering frequency. The droplets flow down one after the other along the metal wire 83. The metal wire 83 protrudes from the capillary 84, and detaches from the metal wire 83 and falls into the bath 811 containing the liquid reagent L, so that the droplet is in the bath. Coating 811. When the dripping substance is filled with the argon-filled device, the bath 811 is removed from the flight tube 85, and the product is rinsed. The melting zone 82 above the flight tube is sometimes interrupted, and a new melting zone is welded in an empty place, thus restarting the device in the next cycle. Fig. 9: Fig. 9 shows the operation of the ingot filling ingot, in which 913 series cone, 914 series test tube, 915 series stopper, 916 series hook, 917 series cover, 918 series neck. 81 and 82 represent the ingot and melting zone as shown in FIG. 8 respectively. The ingot was placed in a coating device by the following method. The ingot was placed in a test tube 914 in a box with an argon flow, and the test tube was sealed with a stopper 915, and then the box was removed in this manner. The large cone 9 1 3 is fixed to the upper part of the melting zone 82 (also visible in Fig. 8), and argon gas is introduced along the test tube 82 from below. A test tube 914 containing an ingot 81 is placed in the cone 913, and the lid is opened to drop the ingot 81. This paper size applies to Chinese National Standard (CNS) Α4 specification (210 × 297 mm) Approved clothing-(Please read the precautions on the back before filling this page)

1T -23-593748 A7 ___ B7 V. Description of the invention (21) The ingot 81 can help the hook 916 move down into the tube of the melting zone 'and remove the test tube 914, the plug 915 and the cone 913. Heating the neck formed on the tube helps the rapid air flow not to be interrupted. The test tube is sealed from the upper cover 9 1 7. After the argon gas is ejected from the upper part of the tube, the neck is sealed to seal the test tube. The device is now ready to drip and coat particles. 10 to 19 are discussed below with reference to Example 7. The comparison table of the main components printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs A Active metal B Fusible stabilizer AB Metal intermetallic mixture of metal A and element B ι Smeltable element B2 Smeltable element C Composition Cl Intermetallic compound C2 Intermetallic Compound C3 Intermetallic compound C4 Intermetallic compound Cl Liquid phase composition Cp Intermetallic compound Ce Eutectic composition L Liquid reagent L Ta Activation temperature Td Equilibrium temperature This paper applies Chinese national standard (CNS) A4 specification (210X 297 mm) (210X 297 mm) ( (Please read the notes on the back before filling out this page)

1T -24-593748 A7 B7 V. Description of Invention (22) Printed by the Consumer Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs

Tf Melting point α Tilt angle (hi-h2) Heating zone (h〇-h2) Cooling zone la Solid shell lb Liquid shell with composition c! 1 c Dispersion layer 2a with composition C 1 + C 2 + ... Intermetallic compound Shell 2b has composition c = C! Shell 2c has composition C! ≪ C < C4 Core 31 B Intermediate layer 41 A metal atom. 42 Growth phase 43 Solid protective coating 51 Cylindrical container 52 Glass test tube 53 Liquid flow 54 Coating of element B 61 Test tube 62 Hopper 63 Ratchet gear 64 Bath liquid 65 Liquid bridge 66 Cylindrical tube (Please read the precautions on the back before filling this page) This paper size applies to China National Standard (CNS) A4 specifications ( 210X 297mm) -25- 593748 A7 B7 V. Description of the invention (23) 67 Cylindrical tube 81 Ingot of mixture AB 82 Melting zone 83 Metal wire 84 Glass film 85 Flight tube 86 Exhaust tube 87 Frosted conical joint 88 Volatile Vapor of metal A 89 Melt of mixture AB 810 Liquid droplet of mixture AB 811 Bath containing liquid reagent 812 High temperature furnace 913 Cone 914 Test tube 915 Stopper 916 Hook 917 Upper cover 918 Neck (Please read the precautions on the back before filling this page) Example printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs Example 1 A thin-walled nickel box containing Nadnn ingots is placed under a heptane layer in a Pyrex test tube, as in Section 5 As shown. Diethylene glycol is scoured from the top to the ingot sheet. The paper size of the ingot applies to the Chinese National Standard (CNS) A4 (210X 297 mm) -26 593748 A7 ___B7 V. Description of the invention (24) (Please read the note on the back first Please fill in this page again to increase the temperature of the ingot to 180 ° C. As soon as a bright liquid indium layer appeared on the surface of the ingot, the temperature of diethylene glycol was immediately lowered to 1 OCTC. After this, it was confirmed that the indium coating had solidified. Stop filling with diethylene glycol. Start with warm water and The box containing the ingot was rinsed with acetone. The entire passivation step takes several minutes. The obtained indium-containing coating ingot can be used as a bulk sodium vapor source in a MBE reaction chamber or as a sublimation aspirator instead of titanium. Example 2 A cylindrical ingot of -20 at% K with a diameter of 14 mm and a height of 40 mm was placed (refer to Figs. 8 and 9) in a Pyrex apparatus for dripping the melt. The capillary (Figure 8) in the center of the membrane 84 has an inner diameter of about 1 mm and a length of about 10 mm. Inside the capillary there is a nickel-chromium wire having a diameter of 0.8 mm, which extends out of the capillary and protrudes out of the capillary by about 3.0 mm from the lower end of the capillary. After the device is evacuated, the aggregate is melted, and the melt falls in a slow temperature rising zone with a droplet formation frequency of 1.0 to 0.25 seconds ^. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the drop drops into a bath containing glycerol. The upper layer of the bath is about 10 cm high and pre-heated to about 80 to 100 ° C, and the lower layer is about 15 cm high. It is room temperature. The hydrogen released during the coating process was continuously removed. When the process is completed, the microparticles are washed with warm water, alcohol to remove glycerol, and dried. The measurement of the thickness of the indium shell showed an average particle size of about 3.0 mm with a coating having a thickness of 80 to 100 microns. Indium-20 at% K particles with an indium coating can be used in organic synthesis. The paper size is applicable to the Chinese National Standard (CNS) Λ4 specification (210X297 mm) -27- 593748 A7 _B7_ V. The description of the invention (25) is taken as Controlled and safe treatment of pure potassium sources or controlled potassium vapor generators used in the manufacture of photovoltaic devices. (Please read the precautions on the back before filling this page} Example 3 The Na22Ga39 microparticle self-dispensing device with a diameter of 1.2 to 1.5 mm falls into a bath of ethylene glycol (Figure 6). The heating zone of the bath has a T ! = 120 ° C and length Ah = 250 mm, the cooling zone has T2 = 10 ° C. Then wash the Na22Ga39 particles coated with gallium shell with temperature not higher than 2 (TC distilled water and propanol) (refer to Figure 6) The steps described above), and finally, dried under vacuum. Another part of particles with the same composition and size fell into the bath containing 2-heptanone. The heating zone of the bath has T! = 120 ° C and length Ah = 250 mm with T2 = 10 ° C in the cooling zone. The product was washed with propanol at 20 ° C and dried under vacuum. To prevent the product from sticking together due to the fusible gallium coating, the product It should be stored at a temperature not higher than 20 to 22 ° C. NanGan particles with a gallium shell printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs are good sodium sources for vacuum applications: The particles can withstand desorption up to 400 ° C in vacuum. Gas, and when heated between 450 and 600 ° C, it will produce the required photocathode Sodium vapor strength. Another area where these microparticles are used is in the chemical reaction of organic synthesis, which requires the use of sodium. Example 4 Spherical microparticles composed of indium lithium with an average diameter of 2 · 8 mm. Zhang scale applies Chinese National Standard (CNS) A4 specification (210X297 mm) -28- 593748 A7 B7 V. Description of the invention (26) The dynamic argon gas is heated to about 180 ° C, and the self-distribution device (Figure 6) falls into 180 ° C and T2 = 25t diethylene glycol bath 64. For the first 20 particles, the length of the heating zone is adjusted to be equal to 220 mm. The coated particles are taken out through the handle 67 and washed with water and alcohol. The results of chemical and metal structural analysis showed that the thickness of the indium shell was about 0.2 mm. The second indium lithium particle composed of 20 was repeatedly covered with the same temperature parameters, but the length of the heating zone was equal to 340 mm. In this example The measurement of the thickness of the indium shell shows a number of 0.35 millimeters. For the third lithium indium particle composed of 20, the heating zone was increased to 700 millimeters, resulting in the thickness of the indium coating growing to about 0.45 millimeters. Indium in the indium shell Lithium particles Excellent working material for evaporable lithium getter. It is also a lithium source for organic synthesis. Example 5 A plurality of tin-40 at% barium alloy self-distribution devices with an average linear size of 1.8 to 2.5 mm (No. Figure 6) Drop into the glycerol bath, L = 245 ° C, T2 = 25 ° C, and the length of the heating zone is 300 mm. The product was washed with temperature and propanol. Chemical analysis showed that the product had tin_ 3 3 at% barium, corresponding to a tin coating thickness equal to approximately 120 microns. This kind of particles can control the source of barium, and can be used in vacuum sealing device as barium vaporizable getter or for precise introduction of barium cations into organic compounds as pure reagents. Example 6 This paper size applies the Chinese National Standard (CNS) A4 specification (2) 0X297 mm. Packing-(Please read the precautions on the back before filling this page) Order printed by the Intellectual Property Bureau of the Ministry of Economic Affairs and Consumer Cooperatives- 29- 593748 Α7 Β7 V. Description of the invention (27) Multiple pieces of Cs2In3 intermetallic compound with an average linear size of 1.8 to 2.0 mm. Use a solution containing 15% malonate in diphenyl ether as described in Example 5. Processing, T! = 170 ° C, T2 = 30 ° C, and the length of the heating zone is 400 mm. The product obtained was first washed off with liquid reagent with isopropanol, then with distilled water and dried under vacuum. Cs2In3 particles coated with indium can be further used in the manufacture of photocathode, as a controllable planing vapor source in organic light-emitting diodes, or as a safety agent in organic compounds containing planing substances. Example 7 In order to confirm the film formation mechanism during the initial treatment of AB solid particles with liquid reagent L, the electron microscope analysis results of Naslnn are shown in Figs. 10 to 19. The above-mentioned microparticles having a diameter of 2.5 to 3.0 mm are exposed at different times in a 165 ° C bath of a 30% solution of stearic acid in a stone ball. After exposure for τ seconds, the microparticles were removed from the bath, washed several times with hot heptane and then analyzed. The data series obtained are shown in Table 2 below. (Please read the notes on the back before filling out this page) Intellectual Property Bureau of the Ministry of Economic Affairs 3 (printed by the Industrial and Consumer Cooperatives). ¾ This paper size applies to China National Standard (CNS) A4 (210X297 mm) -30- 593748 A7 B7 5 、 Explanation of the invention (28) Table 2 Metal structure change test number during the coating process of microparticles Number of time exposed to extractant τ (seconds) Surface state reference 1 0 Homogeneous surface of the compound Figure 10: View of the microparticle before treatment Figure 11 : Elemental analysis of the marked part shows that the composition of the surface is close to the overall composition. 2 1 Independent indium islands appear. Figure 12: Bright spots on the surface. 3 3 Indium island growth system. Figure 13: Obviously on the surface. The number and size of the bright spots increase 4 5 The actual surface of the indium surface Figure 14: Almost the entire surface is bright. Figure 15: Triangular voids (coating defects) of the original surface can be seen when enlarged Figure 16: Bright Partial meta-table analysis shows that the surface is composed of 5 6 continuous inhomogeneous indium surface Figure 17: Particle structure after coating Figure 18: Visible when zoomed in The vacancy in Figure 15 has been repaired. (Please read the precautions on the back before filling out this page)-Binding and binding For comparison, Figure 19 shows the structure of NadnH particles with a diameter of 1.7 mm wrapped in an indium shell. This The microparticles are made by dropping solid spherical particles into a bath containing glycerol, T! = 175 and Ah = 200 mm (Figure 6), and exposed to the specified medium for about 1 second. Consumption by employees of the Bureau of Intellectual Property, Ministry of Economic Affairs Cooperatives printed the conclusions of this embodiment:-the technically continuous formation phase of the protective coating is important, after which the growth thickness of this coating becomes controllable (see Example 4);-by the liquid reagent L and Its chemical composition determines the time when the continuous coating appears. This paper size applies the Chinese National Standard (CNS) A4 specification (210X 297 mm) -31-

Claims (1)

593748 Α8 Β8 C8 D8 6. Scope of patent application 1 Attachment 2A: Patent application No. 9 1 1 22385 Chinese patent application scope replaces April 30, 1993 Amendment 1. A protective coating made on the surface of a chemically active material Layer method, the chemically active material comprises a mixture of a chemically active metal and a soluble stabilizing element, which is characterized by the following steps:-providing at least one chemically active metal A-providing at least one soluble stabilizing element B-mixed metal A and Element B to form a mixture-using liquid reagent L (the liquid reagent L can dissolve metal a but cannot dissolve element B) treats the surface of the mixture at a temperature higher than the melting point of element B, thereby generating substantially Coating consisting of element B-stopping treatment when the coating reaches the desired thickness-removing the liquid reagent and-washing and drying the mixture. 2. The method according to item 1 of the scope of patent application, characterized in that the metal a is selected from alkali metals, alkaline earth metals, rare earth metals and / or radioactive elements. 3. The method according to item 2 of the scope of patent application, characterized in that the metal A is selected from the group consisting of lithium, sodium, potassium, iron, magnesium, calcium, thallium, barium, radium, lanthanum, thorium, bait, thorium, yttrium, Uranium, plutonium and plutonium. 4 · If the method of the first scope of the patent application is applied, it is characterized in that the element B is based on the Chinese standard (CNS) 8 1 ^ (210X297 male H '(Please read the precautions on the back before filling this page) -Order · Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs printed 593748 A8 B8 C8 D8 6. Scope of Patent Application 2 Selected from Group III, IV, V and / or VI elements of the Periodic Table And the binary and ternary combinations between them. 5. The method according to item 4 of the patent application, characterized in that the element B is selected from gallium, indium and / or tin and the binary and ternary combinations between them. 6. The method according to item 1 of the scope of patent application, characterized in that the liquid reagent L is selected from (a) a substance with a higher boiling point and a lower melting point than the melting point of element B, (b) a substance according to (a) And (c) a solution of a substance according to (a) or a mixture thereof (b) in a solvent, which is neutral for metal A and element B. 7. If the scope of patent application is item 6 The method is characterized in that the liquid reagent L is selected from the group consisting of CH-acid and fat Group alcohols, polyhydric alcohols, higher carboxylic acids, condensed aromatic hydrocarbons and / or macrocyclic polyethers, mixtures and solutions thereof. 8) The method according to item 1 of the scope of patent application, characterized in that the temperature is lowered below The processing is stopped below the melting point of element B. 9 · The method according to item 1 of the patent application scope is characterized in that the coating thickness is 1 micron or more. 10 · The method according to item 9 of the patent application scope, wherein the coating The thickness of the layer is 10 micrometers or more. 1 1 The method according to item 1 of the patent application range is characterized in that the thickness of the coating is controlled by adjusting the processing time and / or temperature of the liquid reagent L. 1 2 · If the method of the scope of the patent application is applied, the method is characterized by immersing the metal A and the element B in the liquid reagent L. 1 3 · If the method of the scope of the patent application is applied, the method is characterized by the liquid paper size applicable to China Standard (CNS) A4 specification (210X297 public director) (Please read the precautions on the back before filling out this page), 11 -2- 593748 A8 B8 C8 ——_________ D8 VI. Application for patent scope 3. Type 1 L Then 'metal A and element B The mixture is formed into the desired shape. (Please read the precautions on the back before filling out this page.) 14. The method of item 13 in the scope of patent application, characterized in that the metal a and the element β are treated with the liquid δ-form agent L. The mixture is spherical in nature. 1 5 · The method according to item 13 of the patent application scope is characterized in that the mixture of metal a and element b is formed into a cylindrical or plate shape before being treated with liquid reagent L. 1 6 · For example, the method for applying item No. 14 · in the scope of patent application is characterized in that the spherical mixture is put into the bath of liquid reagent L. 17. A chemically active material with a protective coating on the surface, which is prepared by a method according to any one of claims 1 to 16 of the scope of patent application. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 18. If the chemically active material under item 17 of the patent application scope is used as a vapor source when manufacturing light-emitting devices and organic light-emitting diode products, it is used to manufacture gas filters Used as a chemical absorbent containing evaporable and non-evaporable getters when used in vacuum seals, in the form of catalysts or in the form of constituents of products in chemical synthesis and / or for the manufacture of specific alloys and sublimation Pump and / or particle accelerators are used as a source of active metals. -3- This paper size applies to China National Standard (CNS) A4 specification (210X297 mm)