EP1793950A2 - Desoxydation de poudres metalliques de soupapes - Google Patents

Desoxydation de poudres metalliques de soupapes

Info

Publication number
EP1793950A2
EP1793950A2 EP05782917A EP05782917A EP1793950A2 EP 1793950 A2 EP1793950 A2 EP 1793950A2 EP 05782917 A EP05782917 A EP 05782917A EP 05782917 A EP05782917 A EP 05782917A EP 1793950 A2 EP1793950 A2 EP 1793950A2
Authority
EP
European Patent Office
Prior art keywords
powder
valve metal
tantalum
ppm
deoxidation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP05782917A
Other languages
German (de)
English (en)
Inventor
Josua LÖFFELHOLZ
Ulrich Bartmann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
HC Starck GmbH
Original Assignee
HC Starck GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by HC Starck GmbH filed Critical HC Starck GmbH
Publication of EP1793950A2 publication Critical patent/EP1793950A2/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B5/00—General methods of reducing to metals
    • C22B5/02—Dry methods smelting of sulfides or formation of mattes
    • C22B5/12—Dry methods smelting of sulfides or formation of mattes by gases
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/20—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds
    • B22F9/22—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds using gaseous reductors
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B34/00—Obtaining refractory metals
    • C22B34/20—Obtaining niobium, tantalum or vanadium
    • C22B34/24—Obtaining niobium or tantalum
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B5/00—General methods of reducing to metals
    • C22B5/02—Dry methods smelting of sulfides or formation of mattes
    • C22B5/04—Dry methods smelting of sulfides or formation of mattes by aluminium, other metals or silicon
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H01G9/004—Details
    • H01G9/04—Electrodes or formation of dielectric layers thereon
    • H01G9/048—Electrodes or formation of dielectric layers thereon characterised by their structure
    • H01G9/052—Sintered electrodes
    • H01G9/0525—Powder therefor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H01G9/15—Solid electrolytic capacitors

Definitions

  • the invention relates to a process for the deoxidation of valve metal powders, in particular niobium powders, tantalum powders or their alloys by treating the valve metal powder with a deoxidizer from the group calcium, barium, lanthanum, yttrium and cerium, and valve metal powder, which is characterized by a low content of sodium, Characterize potassium and magnesium.
  • Valve metals including in particular niobium and its alloys, tantalum and its alloys, and the other metals of the group FVb (Ti, Zr, Hf), Vb (V, Nb, Ta) and VIb (Cr, Mo, W) of the Periodic Table of the Elements , As well as their alloys are to be understood, find in the component manufacturing manifold use.
  • niobium or tantalum for the production of capacitors, in particular of solid electrolytic capacitors.
  • niobium or tantalum capacitors In the production of niobium or tantalum capacitors, one usually starts from corresponding metal powders, which are first pressed and then sintered to obtain a porous body. This is anodized in a suitable electrolyte, wherein a dielectric oxide film is formed on the sintered body.
  • the physical and chemical properties of the metal powders used have a decisive influence on the properties of the capacitor. Decisive characteristics are, for example, the specific surface area, the content of impurities and, as the most important electrical parameter, the specific capacity at a given forming voltage U f . Specific capacity is typically expressed in units of microfarads * volts per gram ( ⁇ FV / g).
  • Valve metal powders which are to be used for the production of capacitors, must therefore always meet higher requirements, the content of impurities is very important. This applies, for example, for the content of oxygen in the valve metal powder, which may not be too high, but also for metallic impurities, which significantly affect the leakage current characteristics of the capacitor. These are in particular Na, K, Mg, but also C, Fe, Cr, Ni. In particular, however, the contaminants Na, K and Mg are introduced during the production of the valve metal powder due to the process. Thus, for example, the production of tantalum powder is usually carried out today in accordance with the known from US-A 2,950,185 reduction of K 2 TaF 7 with sodium or potassium, which brings high levels of sodium and potassium in the product with it.
  • tantalum powders having a high oxygen and sodium content can be worked up by adding K 2 TaF 7 and alkali halides and heating the reaction mixture. The levels of oxygen, sodium and potassium can be reduced. But also the powders thus treated have a sodium content of 10 to 87 ppm and a potassium content of 112 to 289 ppm.
  • US Pat. No. 5,442,978 proposes to reduce highly diluted K 2 TaF 7 by the stepwise addition of sodium in order to produce tantalum powder with a high specific surface area and a content of sodium and potassium which is as low as possible, the addition taking place at a high rate.
  • Example 1 can be obtained in this way a tantalum powder with a sodium content ⁇ 3 ppm and a potassium content ⁇ 10 ppm.
  • a deoxidation step is necessary.
  • the tantalum powder is mixed with magnesium and then heated, which leads to the entry of magnesium into the tantalum powder.
  • the impurities sodium, potassium and magnesium cause an increased leakage current due to their high ionic conductivity and the formation of crystalline phases with the generated during the capacitor manufacturing dielectric layer of amorphous valve metal oxide in the electric field or thermal stress in the processing of the capacitor manufacturers. This is particularly pronounced in the increasingly thinner valve metal oxide layers of ⁇ 100 nm, the capacitors have today.
  • (1 V forming voltage corresponds for example to about 2 nm tantalum oxide film thickness).
  • valve metal powders which makes available valve metal powder which characterized by a low content of critical for the residual current of a capacitor elements sodium, potassium and magnesium.
  • Such valve metal powders form very uniform amorphous oxide layers during capacitor fabrication at high specific charge (> 35,000 CV / g).
  • valve metal powder is subjected to a deoxidation step, wherein a deoxidizer is used with low ion mobility.
  • the invention therefore provides a process for the deoxidation of valve metal powders, calcium, barium, lanthanum, yttrium or cerium being used as the deoxidizer.
  • valve metal powders which have a very low content of impurities with high ionic conductivity.
  • the inventive method allows the production of valve metal powders, which have a very low content of impurities with high ionic conductivity.
  • no crystalline phases with the resulting valve metal so that defects in the oxide and high residual currents are avoided.
  • the inventive method is suitable for the deoxidation of a variety of valve metal powder.
  • preference is given to niobium powder, tantalum powder or niobium-tantalum alloy powder, in particular preferably tantalum powder, being deoxidized.
  • the valve metal is therefore preferably tantalum.
  • the deoxidizing agent used is calcium, barium, lanthanum, yttrium or cerium.
  • calcium or lanthanum are used, particularly preferably calcium.
  • the valve metal powder to be deoxidized is mixed with the deoxidizer.
  • This mixture of the valve metal powder with the deoxidizer is heated to a temperature above the melting point of the deoxidizer. Preferably is heated to a temperature which is at least 20 0 C above the melting point of the deoxidizer used.
  • the deoxidation is preferably carried out at a temperature of 880 to 1050 ° C., more preferably at a temperature of 920 to 1000 ° C.
  • the preferred deoxidation temperature is 940 to 1150 ° C., particularly preferably at 980 to 1100 0 C.
  • the deoxidation is preferably carried out at normal pressure. But it is also possible to work at lower pressure.
  • the presence of hydrogen is in the process according to the
  • Invention not required. It can, for example, in vacuum or under inert gas, such as neon, argon or - A -
  • the method does not require a solvent or means for suspending the solids in a liquid phase, such as a molten salt, commonly used in the reduction of valve metal compounds to valve metals.
  • the amount of added deoxidizer and the treatment time can vary within wide limits and depend in particular on the oxygen content of the valve metal powder to be deoxidized and on the deoxidation temperature.
  • a deoxidation time of 2 to 6 hours is usually sufficient.
  • a 1.1 to 3-fold stoichiometric excess of deoxidizer is used, based on the amount theoretically required to reduce the oxygen content to zero. It has been found that it is generally sufficient, the deoxidizer Ca in an amount of 3 to 6 wt .-% and the deoxidizer La in an amount of 6 to 14 wt .-% based on the amount of valve metal powder to be deoxidized To achieve the desired reduction in the oxygen content and the elements sodium, potassium and magnesium.
  • 3.5 to 5.9% by weight of deoxidizer Ca or 9 to 11.5% by weight of La, based on the amount of valve metal powder to be deoxidized are used, more preferably 4 to 4.7% by weight of Ca or 10 to 11, 5 wt .-% La.
  • the oxides of the deoxidizer used in the deoxidation are leached after deoxidation with an acid.
  • the acid used is preferably nitric acid or hydrochloric acid. It should be noted that when using calcium as a deoxidizer, avoid the use of sulfuric acid.
  • the deoxidation of the invention is carried out in two stages.
  • the deoxidizing agent is again added to the valve metal powder after the deoxidation and acid leaching described above and subjected to the described temperature treatment.
  • Amount of deoxidizer is chosen lower in the second deoxidation than in the first deoxidation and preferably corresponds to a stoichiometric excess of
  • the deoxidizer in the second deoxidation step is preferably in an amount of 1 to
  • 3 wt .-% when using La in an amount of 1.5 to 7 wt .-% based on the amount of valve metal powder to be deoxidized.
  • the inventive method is suitable for the deoxidation of arbitrarily produced valve metal powder.
  • niobium and tantalum powders prepared by reducing a fluoride salt of the valve metal with sodium in the presence of a diluting salt can be deoxidized.
  • Such a procedure is known for example from US-A 5,442,978.
  • the liquid melt is stirred under argon atmosphere (1050 hPa) for homogenization.
  • liquid sodium is added in portions.
  • the total amount of sodium corresponds to a 3-6% by weight excess based on the amount of potassium heptafluorotantalate used. It must be ensured during the addition that the temperature in the test retort always remains within the range of the reduction temperature. (T +/- 20 0 C).
  • an additive influencing the surface tension of the molten salt for example anhydrous sodium sulfate, is added to the mixture before the first sodium addition. After completion of the reduction is stirred for 0.5 to 3 hours in the range between 800 0 C and reduction temperature.
  • the reaction mixture is cooled to room temperature and for the passivation of excess sodium, water vapor is passed through the test retort.
  • the retort is then opened, the reaction mixture removed and pre-shredded by jaw crusher ( ⁇ 5 cm, preferably ⁇ 2 cm).
  • the inert salts are then washed out and the resulting tantalum powder is dried.
  • a step of phosphorus doping may be included here, in which the tantalum metal powder is treated with a (NH 4 ) H 2 PO 4 solution to adjust the P content in the final tantalum metal powder. Subsequently, the powder is subjected to a high-temperature treatment in a vacuum.
  • valve metal powders which, as described in US Pat. No. 6,558,447 B1, are obtained by reduction of the valve metal oxides with gaseous magnesium.
  • valve metal powder which is obtained by reducing a valve metal oxide with gaseous calcium, barium, lanthanum, yttrium or cerium is therefore used as the valve metal powder to be deoxidized.
  • tantalum oxide Ti 2 O 5
  • tantalum mesh a tantalum mesh in a tantalum shell.
  • 1.1 times the stoichiometric amount based on the oxygen content in the tantalum oxide is added to calcium, barium, lanthanum, yttrium or cerium.
  • the reduction is carried out at a temperature sufficiently high to convert the reducing agent to the gaseous state. In order to increase the vapor pressure of the reducing agent at a given reduction temperature, it is possible to work in the reactor at a reduced total pressure.
  • Valve metal powders which are characterized by a content of Na, K and Mg of less than 3 ppm, based on a capacity of 10,000 ⁇ FV / g, are accessible for the first time by means of the deoxidation process according to the invention.
  • the invention therefore further valve metal powder having a ratio of sum of the impurities of sodium, potassium and magnesium to capacity of the valve metal powder of less than 3 ppm / 10,000 ⁇ FV / g.
  • the ratio of the sum of the impurities of sodium, potassium and magnesium to the capacity of the valve metal powder is preferably less than 2 ppm / 10,000 ⁇ FV / g, particularly preferably less than 1 ppm / 10,000 ⁇ FV / g.
  • the content of the impurities in K, Na, Mg is determined after an acid digestion of the valve metal sample by means of HNO 3 / HF.
  • K and Na are determined by the method of flame atomic adsorption spectroscopy (FAAS) in an acetylene-air mixture and magnesium by the method of ICP-OES (inductive coupled plasma - optical emission spectroscopy).
  • FAS flame atomic adsorption spectroscopy
  • ICP-OES inductive coupled plasma - optical emission spectroscopy
  • the capacity of the valve metal powder is determined according to the following procedure: From each 0.966 g of a deoxidized valve metal powder cylindrical 4.1 mm diameter and 4.26 mm length cylindrical compacts are produced with a compression density of 4.8 g / cm 3 , wherein in the press pad Prior to filling the valve metal powder axially a tantalum wire of 0.2 mm diameter was inserted as a contact wire. The compacts are sintered at a sintering temperature of 1330 0 C to 1430 0 C for 10 minutes in a high vacuum ( ⁇ 10 '5 m bar) to form anodes.
  • the anode bodies are immersed in 0.1% strength by weight phosphoric acid and formed at a current intensity limited to 150 mA up to a forming voltage of 30 V. After dropping the current, the voltage is maintained for another 100 minutes.
  • a cathode of 18 wt .-% sulfuric acid is used. It is measured at a frequency of 120 Hz. Subsequently, the residual current is measured in phosphoric acid of conductivity 4300 ⁇ S.
  • the valve metal powders according to the invention preferably have a capacity of at least 35,000 ⁇ FV / g, more preferably of at least 40,000 ⁇ FV / g.
  • the valve metal powders according to the invention are preferably niobium or tantalum powders, these optionally being doped with one another and / or with one or more of the metals Ti, Mo, V, W, Hf and Zr. Other dopants, such as phosphorus, are possible.
  • valve metal powders according to the invention can be used for a wide variety of applications and are particularly suitable for the production of solid electrolytic capacitors.
  • a tantalum primary powder was prepared starting from a mixture of 150 kg K 2 TaF 7 , 136 kg KCl, 150 kg KF, 4 kg of a high-purity tantalum powder and 300 g Na 2 SO 4 in a nickel-coated DSfCONEL retort by incremental addition of sodium a reduction temperature of 900 0 C prepared analogously to US-A 5,442,978.
  • the tantalum powder was isolated from the cooled and comminuted reaction mixture by washing with slightly acidified water, followed by a final purification treatment with a wash solution containing sulfuric acid and hydrogen peroxide.
  • the material was doped with 20 ppm phosphorus with a sodium dihydrogen phosphate solution containing 1 mg P per ml of solution.
  • the phosphorus content of the tantalum powder was adjusted to 60 ppm by means of the sodium dihydrogen phosphate solution (1 mg P per ml).
  • the powder had the following impurities (in ppm):
  • the powder thus prepared had the following impurities: Mg: ⁇ 1 ppm Na: 1 ppm K: 8 ppm
  • the electrical test showed a capacity of 37419 ufv / g at a sintering temperature of 1400 0 C.
  • the powder thus prepared had the following impurities: Mg: 8 ppm Na: 1 ppm K: 6 ppm
  • the electrical test showed a capacity of 38261 ufv / g at a sintering temperature of 1400 0 C.
  • Example 2 200 g of the starting powder from Example 1 were mixed with 22 g of lanthanum powder (11 wt .-%) and brought in a covered tantalum crucible in a retort under argon atmosphere for 3 h at 980 0 C. After cooling and controlled air feed for passivation, the reaction mixture was removed and formed lanthanum oxide was removed with a wash solution of dilute nitric acid and hydrogen peroxide solution. The wash solution was decanted off and The powder on the suction filter washed acid-free with demineralised water. The dried powder had an oxygen content of 3045 ppm.
  • this powder 180 g of this powder were now subjected to a second deoxidation step.
  • 6.5 g of lanthanum powder (based on the oxygen content of 1.5 times the stoichiometric amount) were mixed under the powder and this mixture was also heated to 980 0 C for 3 h. After cooling and passivating, the La 2 Oa formed was again removed by an acid wash, and the powder was washed free of acid.
  • the powder thus prepared had the following impurities: Mg: ⁇ 1 ppm Na: 0.7 ppm K: 8 ppm
  • the electrical test showed a capacity of 38093 ufv / g at a sintering temperature of 1400 0 C.
  • a tantalum primary powder was added starting from a mixture of 75 kg K 2 TaF 7 , 125 kg KCl, 225 kg KF, 5 kg high-grade tantalum powder and 500 g Na 2 SO 4 in a nickel-coated INCONEL retort by incremental addition of sodium a reduction temperature of 920 0 C prepared analogously to US-A 5,442,978.
  • the tantalum powder was isolated from the cooled and comminuted reaction mixture by washing with slightly acidified water, followed by a final purification treatment with a wash solution containing sulfuric acid and hydrogen peroxide.
  • the material was doped with 100 ppm phosphorus with a sodium dihydrogen phosphate solution containing 1 mg P per ml of solution. After drying, a temperature treatment in a high vacuum at 1280 0 C was performed.
  • the powder had the following impurities (in ppm): Mg: ⁇ 1 ppm Na: 1 ppm K: 49 ppm
  • the powder thus prepared had the following impurities: Mg: ⁇ 1 ppm Na: 1 ppm K: 12 ppm
  • the electrical test showed a capacity of 59764 ufv / g at a sintering temperature of 1400 0 C.
  • tantalum pentoxide Ti 2 O 5
  • a particle size ⁇ 400 ⁇ m 500 g are placed on a tantalum mesh in a tantalum crucible.
  • 1.1 times the stoichiometric amount based on the oxygen content in tantalum pentoxide is added to calcium (249.4 g).
  • the tantalum shell is placed in a sealable retort.
  • the reduction is carried out at 980 ° C. and under a pressure of 600 mbar under an argon atmosphere for 8 hours.
  • the reaction mixture is removed and the resulting calcium oxide is leached with nitric acid.
  • the acid-free washed tantalum powder is on the suction filter with a Natriumdihydrogenphosphatans containing 1 mg P per ml solution containing 100 ppm P and then dried.
  • the tantalum powder thus prepared has an oxygen content of 7143 ppm.
  • the washing solution is decanted off and the powder on the Washed with demineralized water acid-free.
  • the dried powder has an oxygen content of 4953 ppm.
  • the powder thus prepared has the following impurities:
  • the electrical test showed a capacity of 70391 CV / g at a sintering temperature of 1400 0 C.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Manufacturing & Machinery (AREA)
  • Power Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Powder Metallurgy (AREA)

Abstract

L'invention concerne la désoxydation de poudres métalliques de soupapes, notamment de poudres de niobium, de tantale ou leurs alliages, par traitement de la poudre métallique avec du calcium, du baryum, du lanthane, de l'yttrium ou du cérium en tant qu'agent de désoxydation. La présente invention porte également sur des poudres métalliques de soupapes qui se caractérisent par un rapport entre la somme des teneurs en sodium, potassium et magnésium et la capacité inférieur à 3 ppm/10 000 ?FV/g.
EP05782917A 2004-09-08 2005-08-26 Desoxydation de poudres metalliques de soupapes Withdrawn EP1793950A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102004043343A DE102004043343A1 (de) 2004-09-08 2004-09-08 Desoxidation von Ventilmetallpulvern
PCT/EP2005/009230 WO2006027119A2 (fr) 2004-09-08 2005-08-26 Desoxydation de poudres de métaux valves

Publications (1)

Publication Number Publication Date
EP1793950A2 true EP1793950A2 (fr) 2007-06-13

Family

ID=35445804

Family Applications (1)

Application Number Title Priority Date Filing Date
EP05782917A Withdrawn EP1793950A2 (fr) 2004-09-08 2005-08-26 Desoxydation de poudres metalliques de soupapes

Country Status (15)

Country Link
US (1) US20080011124A1 (fr)
EP (1) EP1793950A2 (fr)
JP (1) JP2008512568A (fr)
KR (1) KR20070098988A (fr)
CN (1) CN101052488A (fr)
AU (1) AU2005281918A1 (fr)
BR (1) BRPI0515172A (fr)
DE (1) DE102004043343A1 (fr)
IL (1) IL181782A0 (fr)
MX (1) MX2007002717A (fr)
RU (2) RU2404881C2 (fr)
SV (1) SV2006002222A (fr)
TW (1) TW200624200A (fr)
WO (1) WO2006027119A2 (fr)
ZA (1) ZA200701902B (fr)

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CN101574741B (zh) * 2009-06-25 2011-05-18 宁夏东方钽业股份有限公司 电容器用钽粉的制备方法
CN105377481B (zh) * 2014-02-27 2018-02-06 宁夏东方钽业股份有限公司 一种高纯钽粉及其制备方法
FR3038623B1 (fr) * 2015-07-10 2017-06-30 Fives Procede permettant de retirer les oxydes presents a la surface des nodules d'une poudre metallique avant l'utilisation de celle-ci dans un procede industriel
CN107236868B (zh) 2017-05-23 2019-02-26 东北大学 一种多级深度还原制备高熔点金属粉的方法
CN112828279B (zh) * 2020-12-31 2022-08-12 昆明理工大学 一种金属粉末气相脱氧方法

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Also Published As

Publication number Publication date
WO2006027119A3 (fr) 2006-06-15
AU2005281918A1 (en) 2006-03-16
US20080011124A1 (en) 2008-01-17
DE102004043343A1 (de) 2006-03-23
JP2008512568A (ja) 2008-04-24
RU2010116085A (ru) 2011-10-27
IL181782A0 (en) 2007-07-04
ZA200701902B (en) 2008-08-27
RU2404881C2 (ru) 2010-11-27
MX2007002717A (es) 2008-03-11
RU2007112796A (ru) 2008-10-20
SV2006002222A (es) 2006-05-25
KR20070098988A (ko) 2007-10-08
WO2006027119A2 (fr) 2006-03-16
TW200624200A (en) 2006-07-16
CN101052488A (zh) 2007-10-10
BRPI0515172A (pt) 2008-07-08

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