JPH0564724B2 - - Google Patents

Description

[Detailed description of the invention]

FIELD OF THE INVENTION The present invention relates to measuring the volume of objects. More specifically, by changing the gas density in the sealed container containing the balance, we will calculate (a) the mass or weight of the sample to be measured in the sealed container, and (b) the mass of the sample to be measured corresponding to the amount of change in gas density. or (c) a change in gas density to determine the volume of a sample to be measured, and a volume measuring device comprising a sealed container containing a balance. . Furthermore, since the present invention uses a balance to determine the volume, the true mass (hereinafter abbreviated as "mass") of the sample shown in vacuum can be found at the same time as the volume, and the true density of the sample shown in vacuum. The present invention also relates to a method and apparatus for determining specific gravity (hereinafter abbreviated as density). [Background of the Invention] In recent years, measurement methods have been streamlined in connection with the international unification of units. For this reason, convenient measuring instruments have been devised and abundantly available for basic measurements of length, mass, time, etc., but progress in measuring instruments for volume measurement has lagged behind. [Conventional Techniques and Problems] Taking the JIS standard as an example of the conventional volume measurement method, there are, for example, the following methods. JIS R 3505 Glass chemical volume meter JIS K 0061 Method for measuring the specific gravity of chemical products JIS Z 8804 Method for measuring the specific gravity of liquids JIS Z 8807 Solid JIS M 8716 Method for measuring the apparent specific gravity and porosity of iron ores (pellets) JIS M 8717 Method for measuring the true specific gravity of iron ores JIS R 5201 Physical test method for cement JIS A 1109 Method for testing the specific gravity and water absorption of fine aggregate JIS A 1110 Method for testing the specific gravity and water absorption of coarse aggregate JP 51-67158 Since the measurement of specific gravity or density is accompanied by the measurement of volume, they were set in the same range. Each of these methods has its own characteristics and is widely used in specific fields, but the drawbacks are that the methods that allow quick measurements lack precision, and the methods that are highly accurate are complicated and require time to measure. It lacks versatility. For example, there are restrictions on samples such as liquids, solids, and powders. A liquid that does not dissolve the sample is required.
It is necessary to apply pressure and there are restrictions on the sample. You can list the shortcomings of each. Therefore, it is desired to develop a versatile method and apparatus for measuring volume that can be applied to almost any sample that exhibits a constant volume in the atmosphere. [Purpose of the Invention] As a result of conducting studies to meet these demands, we have developed a method for measuring volume that is highly versatile, quick, and accurate, using a balance, that is, a gas density balance or gas specific gravity balance, and a solid balance. The present invention was completed with the aim of directly measuring the volume of a sample. [Summary of the Invention] A method for measuring specific gravity is Archimedes' method, which has been famous since ancient times. This is still used today as a method for measuring density and specific gravity, and is also adopted in the JIS standard. This principle involves suspending the sample in a liquid,
The density is determined from the apparent mass in the atmosphere and its liquid.In other words, the volume of the sample is determined from the buoyancy of the sample in the liquid and the density of the liquid.
In turn, it is used to determine density, and is often used as a highly accurate measurement method. However, since the sample needs to be immersed in a liquid, it is limited to solid samples, and it is also necessary to prepare a liquid that does not dissolve the sample and determine the density of the liquid in advance by another method, which reduces versatility and speed. It has the disadvantage of being inferior. The present invention is based on the application of Archimedes' principle, which states that when a sample is immersed in a fluid, it experiences a buoyancy force of a mass of the fluid equal to the volume occupied by the sample. In Archimedes' method,
The present invention was completed by discovering that the volume of a sample can be determined by combining mass measurement between air and liquid and simultaneously measuring the density of the gas. That is, the method of the present invention measures the apparent mass of a sample using a solid balance in the usual manner, and then changes the density of the gas in a density container containing a gas density balance or a gas specific gravity balance and a solid balance, Measure the change in apparent mass of the sample ΔG. At the same time, it is based on finding the sample volume Vm from the change in gas density Δρ. That is, the following equation is established based on Archimedes' principle, and the volume can be measured. Vm=ΔG/Δρ (1) [Detailed Description of the Invention] The present invention changes the gas density in a density container containing a balance, and changes the mass or weight of (a) the sample to be measured in the sealed container, and ( b) the amount of change in the mass or weight of the sample to be measured corresponding to the amount of change in gas density;
(c) The present invention relates to a volume measuring method characterized by measuring the amount of change in gas density and determining the volume of a sample to be measured, and a volume measuring device comprising a density container having a balance therein. More specifically, the present invention uses a gas density balance or a gas specific gravity balance to measure gas density,
and one or two gases that do not react with the sample to be measured.
Volume measurement method consists of a volume measurement method that uses more than one species, a density container containing a balance, and the balance is a gas density balance or gas specific gravity balance for measuring gas density, and a balance for measuring the mass or weight of the sample to be measured. It is related to the device. Volume calculation formula The principle of the present invention is shown in formula (1), but in actual solid balances, the volume of weights, rods, etc. has an influence, and (1)
The formula is not applied as is. Therefore, the measurement theory calculation formulas of the present invention for the cases of [1] equal rod balance, [2] lever balance, and [3] ground motion balance are shown in Figures 1 and 2, which are schematic diagrams showing one embodiment of the present invention.
According to the figure, it is shown below. [1] Balance Figure 1 shows an isobar balance 1 and a gas density balance or gas specific gravity balance 2 (for example, a Lux gas balance,
1 is a schematic diagram showing an embodiment of the present invention using a gas balance (such as a Taylor gas balance). M is the mass of the sample to be measured 3 (the mass or weight shown in a vacuum not affected by buoyancy), and the apparent mass (the mass or weight shown in the atmosphere affected by buoyancy, that is, the normal weighing value) Let Ma and the volume be Vm, the mass of the weight is G, the apparent mass is Ga, the volume is Vg, the density is ρg, and the density of the gas in the container in which the balance is placed is ρ. In the equal rod balance 1, the left and right sides of the rod are of equal length, so the volume and mass are also symmetrical, and the influence of buoyancy is eliminated. Therefore, if the sample to be measured 3 and the weight 4 are balanced, the following equation holds true. Ma=Ga (2) From Archimedes' principle, apparent mass is equal to mass minus buoyancy. Ma=M−ρVm (3) Ga=G−ρVg (4) From equations (2) to (4), M=G+ρ(Vm−Vg) ( ₅ ) The method of the present invention Read the apparent weight value (weight reading) G ₁ and the volume of the weight Vg ₁ , then calculate the gas density from ρ ₁ to ρ ₂
and read G ₂ and Vg ₂ respectively, so
From equation (5), the following equation is established. M=G ₁ +ρ ₁ (Vm−Vg ₁ ) (6) M=G ₂ +ρ ₂ (Vm−Vg ₂ ) (7) Equation (7) − Equation (6) Vm=G ₂ −G ₁ /ρ ₁ − ρ ₂ +Vg ₁ ρ ₁ −Vg ₂ ρ ₂ /ρ ₁ −ρ ₂ (8
) From this equation (8), Vm can be found. An improved method of the invention is the measurement of (G ₂ − G ₁ )≡ΔG, i.e. the difference in weight readings (equal to the difference in buoyancy) when changing the gas density in the container from ρ ₁ to ρ ₂ . When measuring methods that do not cause volume changes in the measurement system (6 in Figure 1), such as changing the position of the lidar weight, inclination angle of the rod, elastic force, electromagnetic force, capacitance, piezoelectric effect, etc. , Vg ₁ = Vg ₂ ≡
Vg, so equation (8) becomes Vm=Vg+ΔG/ρ ₁ −ρ ₂ (9). Here, by setting ρ ₁ −ρ ₂ =Δρ, the following equation is obtained. Vm=Vg+ΔG/Δρ (10) In other words, the volume Vm of the sample to be measured can be found from the volume Vg of the weight, the difference ΔG in the weighing readings, and the difference Δρ in the gas density using equation (10), which is a practical method. becomes. [2] Lever Balance FIG. 2 is a schematic diagram showing an embodiment of the present invention using a lever balance (unequal ratio rod balance) 11 and a gas density balance or gas specific gravity balance 2. The mechanism of lever balances is used in direct reading balances, automatic balances, electronic balances, etc. In the lever balance 11, its symbol is the same as that of the equal rod balance in the previous section, and in addition, the mass of the balance weight 9 is W, its apparent mass is Wa, its volume is Vw, its density is ρw, and the length of the rod from the fulcrum to the center of gravity is Let the lengths of be la and lb, respectively. However, G in the lever balance is the total mass applied to the fulcrum 12 on the weighing pan side. Note that when finding the balance of the lever balance, the effects of unequal ratios such as the volume and mass of the rod are ignored, assuming that they are always constant (a practical correction method will be described later). (b) When no sample is placed First, with no sample placed, determine the amount of change ΔG in the solid balance reading when changing the gas density in the container. The balance of the lever balance in gas is: Ga=lb/laWa (11) Ga=G−ρVg (12) Wa=W−ρVw (13) ∴G=ρVg+lb/la (W−ρVw) (14) This invention The density of the gas is calculated from ρ ₁ to ρ ₂ based on the method of
_{When changing to _} W−ρ ₂ Vw)ΔG ₀ (16) Equation (16) − Equation (15) ΔG ₀ = (Vg−lb/laVw)(ρ ₁ −ρ ₂ ) (17) The following equation holds true for the lever balance. (Vg - lb / laVw) = constant≡k (18) ∴ΔG ₀ = k (ρ ₁ - _{ρ 2} ) = k・Δρ (19) In other words, even when the sample is not measured, the lever balance changes the value from ρ ₁ to ρ. A change in ₂ produces ΔG ₀ proportional to the difference Δ. Note that since the influence of the volume of the rod etc. appears in reality, k changes slightly depending on the values of ρ ₁ and ρ ₂ . Therefore, the lever balance of the present invention has k≒0, that is, ΔG ₀ ≒0
It is preferable to adopt a device that satisfies the following. In other words, as a practical correction method, the ΔG
The adjustment method for ≒0 is k≒0 in equation (18).
This can be done by satisfying the following conditions. k＝Vg−lb／laVw≒0 (20) Vg≒lb／laVw (21) G／ρg≒lb／la・W／ρw (22) The rod is of
By adjusting the ratio of lb/la, the mass and apparent volume of the weight and balance weight (by using a hollow weight and adjusting the apparent density, etc.) and selecting G, W, ρg, and ρw appropriately, ΔG≒ It can be set to 0. (b) When a sample is placed on it Normally, when measuring the mass using a lever balance, after placing the sample M on the weighing pan, remove the weight 5:Gm that corresponds to the sample M from the weights 4, balance it with W, and measure it. do. Therefore, the volume changes each time depending on M and ρm. Considering the balance in gas, the lever balance is a displacement weighing method, so Ma=Gma (23) Ma=M−ρVm (24) Gma=Gm−ρVgm (25) ∴M=Gm+ρ(Vm−Vgm) ( 26) In other words, an equation of the same form as equation (5) of the isobad balance is obtained. However, Gm in this case is the reading of weight 5, which was removed for balance, and Ma,
Gm is each apparent mass (a value that includes the effect of buoyancy). In the method of the present invention, the difference in apparent mass ΔG of the sample M is determined by changing the gas density from ρ ₁ to ρ ₂ . However, with a lever balance, a difference of ΔG ₀ occurs even when M=0, so the apparent mass difference ΔGa appearing on scale 6
is the following equation, where Δg is the difference corresponding to ΔG in equation (10). ΔGa=ΔG ₀ +Δg (27) When the gas density is changed from ρ ₁ to ρ ₂ , the following equation holds from equation (26). M=Gm+ρ ₁ (Vm−Vgm) (28) M=Gm+ρ ₂ (Vm−Vgm)Δg (29) Equation (29)−(28) Vm=VgmΔg/Δρ (30) However, Δg=ΔGa−ΔG ₀ = ΔGa−k・Δρ In addition, in the lever balance with k≒0, ΔG ₀ ≒0, Δg=
ΔGa, which is isomorphic to equation (10). [3] Automatic balances The automatic balances described here are different from electronic balances, torsion balances, spring balances, piezo balances, etc., which do not add or subtract weights, but instead use the inclination of a rod, electromagnetic force, elastic force, and piezo effect. , a general term for solid balances that measure mass or weight using pressure, etc.
In other words, the measurement system is a solid balance that does not cause volume changes. This automatic balance generally measures weight, and weight =
It is expressed as mass (acceleration of gravity g′ = constant).
Here, the indicated value G is assumed to be mass, assuming that gravity is verified to be equal to mass. Therefore, the following equation holds. Ma=G (31) Ma=M−ρVm (32) ∴M=G+ρVm (33) In the method of the present invention, the gas density in the sealed container is ρ ₁
Since we change from to ρ ₂ , the following equation holds true. M=G ₁ +ρ ₁ Vm (34) M=G ₂ +ρ ₂ Vm (35) Equation (35)-(34) (G ₂ − G ₁ )=Vm (ρ ₁ −ρ ₂ ) Vm=ΔG/Δρ ( 36) The above results are summarized in Table 1.

【table】

[Table] As can be seen from the calculation formula in Table 1, the method of the present invention requires the measurement points of ΔG and Δρ, and requires the use of a solid-state balance with high detection sensitivity. This detection sensitivity is expressed by the value of minimum detection amount/weighing amount (hereinafter abbreviated as accuracy ratio), assuming that the effective value of volume measurement is 3 digits, the density of the sample is 1 to 2 g/cm ³ , and the value is: i. When the gas combination is air-carbon dioxide or air-helium gas, it is approximately 10 ^-6 to 10 ^-7 (accuracy ratio 0.1 mg/100 to 200).
g), b. Air - 10 ^-5 to 10 ^-6 for SF gas
(accuracy ratio 1mg/100~200g), c. In the case of a combination of 1 atm of air and 10 atm of air, the result is 10 ^-5 to 10 ^-6 (accuracy ratio of 1 mg/100 to 200 g), which is easy if the current high-sensitivity solid balance is used. Below, as supplementary information, we will discuss methods for measuring mass and density, as well as matters related to volume measurement. Method for Measuring Mass and Density Since the volume can be measured using a solid balance from the volume calculation formula in Table 1, the true mass can be determined from the apparent mass weighed at the same time. The calculation formula for this mass measurement method is as follows. Equal rod balance Substitute equation (10) into equation (6) M=G ₁ +ρ ₁ ΔG/Δρ (37) Lever balance Substitute equation (30) into equation (28) M=Gm+ρ ₁ ΔG/Δρ (38 ) Automatic balance Substitute equation (36) into equation (35) M=G ₁ +ρ ₁ ΔG/Δρ (39) In other words, the mass of the weight balanced with the sample G ₁ to Gm, the gas density ρ ₁ at that time, and the sample The mass M of the sample can be determined from the volume difference ΔG/Δρ or Δg/Δρ between the weight and the weight. Since the volume Vm and mass M of the sample are determined by the method of the present invention, the density ρm of the sample (density in vacuum) is determined by the following equation. ρm=M/Vm (40) Supplementary information regarding measurement Method for changing gas density The most preferable method for changing the gas density in a sealed container is to change the type of gas (gas replacement method). This is because it is easy to implement and the pressure in the measurement system can be kept constant, so that samples that change in volume due to pressure changes can be measured. This means that the volume, mass, and density of a gas contained in a container (for example, a rubber balloon, a glass hollow sphere, etc.) can be measured, and the average molecular weight can also be determined by measuring the pressure of the sample gas. The type of gas should be a gas that does not react with the sample or cause an adsorption phenomenon, and the combination is preferably one in which the gas densities are significantly different. Also, it is preferable to use a liquefied gas that is easy to use. These types include air, carbon dioxide, propane, butane, sulfur hexafluoride,
Inert gases in group 0 of the periodic table, such as hydrogen and helium,
These include nitrogen, oxygen, and fluorochlorinated hydrocarbons. From the viewpoint of safety and handling, a combination of air and carbon gas or helium gas is recommended. Furthermore, as a method of changing the gas density within the sealed container, there is a method of changing pressure or temperature. Since this method can be easily inferred, the examples are omitted. Alternative Methods for Measuring Gas Density Although the main method for measuring gas density is to use a gas density balance (gas specific gravity balance), other methods may also be used. An example of this is a method using a standard sample of known volume. This is to weigh the standard sample and the sample to be measured in parallel. That is, by using a standard sample, a normal solid balance can be used as a gas density balance. In this case, the calculation formula is: Vms is the volume of the standard sample, Vgs is the volume of the weight that balances when weighed with this, and ΔGs is the amount of change in the mass of the weight that balances when the gas density is changed from ρ ₁ to ρ ₂ . Then, the amount of change Δρ in gas density required when measuring the volume of the sample is determined by the following equation, which is a modification of equation (10). Δρ=ΔGs/Vms−Vgs (41) However, Vms≠Vgs (ρms≠ρgs) Similarly, mass measurement can be carried out by using a standard sample whose volume Vms and mass Ms are known. That is, the gas density ρ ₁ required for mass measurement is expressed as follows. ρ ₁ = Ms − Gs / Vms − Vgs (42) The standard sample may be a weight of a solid balance, and one or more of the weights of a solid balance may be weights with widely different densities, or a lever balance may be used. In this case, it is preferable to use a method in which the volume of the lever weight is known. Note that the smaller the density of the standard sample, the more preferable it is. For example, if a glass bulb with a volume of 200 ml and a mass of 100 g is used as a standard sample, the density of the weight of a solid balance is
8.0g/cm ³ , and when the gas density is changed using the air-carbon dioxide system gas replacement method, ΔGs in equation (41) becomes
The weight is 0.1153g, and sufficient accuracy can be obtained using a commercially available solid balance (25°C, 1 atm). Others Generally, the volume and density of a sample change with temperature and pressure, so it is necessary to maintain a solid-state balance at a constant temperature and pressure during weighing, and it is preferable to add a temperature control and pressure control device. One simple method is to house the weighing mechanism of a solid-state balance in a metal block to reduce temperature changes and temperature unevenness. This method is preferable because it reduces the influence of external electromagnetic force, etc., and in the case of gas replacement, the amount of gas replaced is small and rapid replacement is possible. The method and device of the present invention can directly apply a conventional solid-state balance mechanism to measure volume.
It is preferable to automate calculations and display by introducing a servo mechanism, a computer, etc. If the sample is a fluid such as powder or liquid, a sample container is required. In this case, use a container whose volume and mass are known, and calculate the volume and mass of the sample excluding the container. Note that it is preferable to make the density of the sample container the same as the weight of the solid balance, since the influence of the volume of the sample container will not appear on ΔG, which will reduce measurement errors and speed up the measurement. As an example, an example using an equal rod balance and a lever balance is shown below. Note that automatic balances are omitted because they can be easily inferred from these examples. [Example] [1] Example 1, Comparative Example 1 Example 1 The solid balance is an isobad balance (Shimadzu Corporation - chemical balance type 11) with a weighing capacity of 200 g, a sensitivity of 1.0 mg, and a minimum detection amount of 0.1 mg.
and a weight of 200 g to 0.1 g (density 8.40 g/cm ³ ), and dry the solid balance in a polyethylene bag (corresponding to 7 in Figures 1 and 2) to replace the gas in the sealed container. The gas density in the sealed container was changed by changing the type of gas in the sealed container.First, the sample to be measured was weighed in the atmosphere, and then carbon dioxide was poured into a polyethylene bag. The replacement was carried out by introducing from the bottom and releasing the upper part to the atmosphere.As Example 1, Sample A: Pure magnesium block (approximate dimensions 55.1 mm x 42.5 mm x 38.4 mm cube, purity
99.97%) volume was measured. The amount of change in gas density Δρ is measured using a standard sample, and the volume Vms is used as the standard sample.
= 115.75 cm ³ , mass Ms = 149.9955 g, and a hollow glass bottle with a tightly stopper was used. [Measurement operation] In the measurement operation, first, the level and zero point of the solid balance were adjusted, and then sample A and the standard sample were each weighed in the atmosphere to determine the apparent masses G and Gs. Subsequently, the gas in the sealed container was replaced from air to carbon gas by the method described above, and it was weighed again to determine the apparent masses G ₂ and Gs ₂ in carbon dioxide gas. The measurement operation time during this period was 8 minutes. In addition,
The temperature inside the sealed container was 25.2°C and the atmospheric pressure was 755 mmHg. As a result of this measurement, sample I G ₁ = 156.1125 g, G ₂
= 156.0684g, standard sample Gs ₁ = 149.8809, Gs ₂ =
149.8202g was obtained. Note that the shift of the zero point due to carbon dioxide gas replacement was negligible. [Volume calculation] First, the gas density difference Δρ was calculated from the measured values of the standard sample using equation (41). However, measurements of less than 0.1g are determined by the amount of movement of the rider and the movement of the stationary point (method determined from the amplitude value), regardless of the weight.
The values of Vg and Vgs were calculated using the readings of weights of 0.1 g or more (the density of the weight
8.40g/ ^cm3 ). Δρ=149.8809−149.8202/115.75−149.8/8.40=0.000620 g/cm ³ The volume Vm of sample A was calculated using equation (10). ∴Vm=156.1/8.40+156.1125−156.0684/0.00062 =89.71cm ³ [Calculation of mass and density] Mass (mass in vacuum) M is calculated using equations (42) and (37). density)
ρm was determined using equation (40). ρ ₁ = 149.9955−149.8809/115.75−149.8/8.40=0.00
117g/ ^cm3 ∴m=156.1125+0.00117×156.1125−156.0684/0.000
62 = 156.1957g ∴ρm = 156.1957/89.71 = 1.741g/cm ³ Comparative Example 1 As Comparative Example 1, using sample A, JIS M 8807
-1976 Volume Vm, mass M and density ρm by weighing in water in accordance with Section 4 of Solid Specific Gravity Measurement Method
I asked for Note that when sample A was weighed in water, it was first immersed in water, degassed under reduced pressure, and weighed after no air bubbles were formed. The measurement operation time during this period was 120 minutes. In addition, the mass M is corrected for buoyancy from the value of the apparent mass G shown in the atmosphere (method described in Rika Nendo 431-1985).
I did this and found out. The measurement results for sample A are Vm=89.77cm ³ , M=
It was 156.1968 g and ρm = 1.740 g/cm ³ . [2] Example 2, Comparative Example 2 Example 2 As Example 2, measurement was performed in the same manner as in Example 1, except that sample B: Toyoura standard sand was used. However, since sample RO is a powder, use an aluminum square plate (11 x 16.5 x 2.5 cm) with a volume of 16.49 cm ³ and a mass of 44.5125 g as a container, weigh the total amount with sample RO, and calculate the value of the container. I did it by removing it. The measurement time was 20 minutes. This measurement result shows that Vm=55.65cm ³ and M=
It was 146.9227 g, ρm = 2.64 g/cm ³ . Comparative example 2 As comparative example 2, using sample RO, JIS R
The volume was measured using a Les Chatellier pycnometer in accordance with Section 6 of Physical Test Methods for 5201 Cement.
The measurement time required 18 hours. Note that sample B was a powder, and due to the scale of the Lusciatelier pycnometer, it was not possible to make it the same amount as in Example 2, so the mass was converted to the same value from the measured value. The measurement results are Vm=55.9cm ³ , ρm=2.63g/
It was warm at ^cm3 . [3], [4] Examples 3, 4 Comparative Examples 3, 4 Examples 3, 4 As Example 3, sample C: 100 pieces with the upper part cut off.
Measurement was performed in the same manner as in Example 1, except that a ml graduated cylinder and Example 4 used sample 2: about 100 ml of pure water and replaced carbon dioxide gas with butane gas. However, since Sample D is a liquid, the same method as in Example 2 was carried out using Sample C as a container. The measurement time was 10 minutes. The temperature inside the sealed container is 25.2℃ in the case of air, and 25.2℃ in the case of butane gas.
The temperature was 24.6°C and the atmospheric pressure was 755mmHg. The measurement results are as follows: Sample Vm = 43.15cm ³ , M = 97.5230g, ρm =
2.26g/cm ³ , Sample Ni Vm=100.16cm ³ , M=100.0603
g, ρm=0.999 g/cm ³ . Comparative Examples 3 and 4 Sample C was used as Comparative Example 3, and sample D was used as Comparative Example 4. First, an attempt was made to measure Sample C using the same method as Comparative Example A, but the measurement was discontinued because it required modification of the balance device to lower the sample underwater. For sample 2, only the volume was measured, and the volume was read from the graduated cylinder scale of sample 2, which was used as a container. The measurement results are as follows: Sample size Vm = 100.0 cm ³ [5] to [8] Examples 5 to 8, Comparative Examples 5 to 8 Examples 5 to 8 The solid balance has a weighing capacity of 160 g, a sensitivity of 1 mg, and a minimum scale.
0.1mg lever balance direct indicator balance (manufactured by Mettler)
H10T type weight density 8.4 g/cm ³ ) was used. As Examples 5 to 8, sample E: pure magnesium ingot (sample A was used), sample H: about 50 g of brass ingot (weight), sample G: glass bulb with outer diameter of about 24 mm, and sample H: outer diameter Each sample was measured in the same manner as in Example 1, except that a hollow glass bulb containing approximately 31 mm of air was used. The measurement time was 14 minutes. However, since it is a lever balance, changing the gas density will cause the zero point of the solid balance to move, so the value of this movement amount ΔG is measured and the calculation formula, equation (30),
Equations (38) and (40) were used. The results of this measurement were as follows. Sample Vm = 89.76cm ³ , M = 156.1955g ρm = 1.740g/cm ^3rd sample Vm = 5.95cm ³ , M = 49.9994g ρm = 8.40g/cm ^3rd sample Vm = 7.77cm ³ , M = 17.3550g ρm = 2.23g/cm ³ sample samples Vm = 15.50cm ³ , M = 19.2774g ρm = 1.24g/cm ³ Comparative Examples 5-8 As Comparative Examples 5-8, samples corresponding to Examples 5-8 were compared. It was measured by the method shown in Example 1.
The measurement time was 180 minutes. The measurement results were as follows. However, sample E and sample B are the same. Sample Vm = 87.77cm ³ , M = 156.1968g ρm = 1.740g/cm ^3rd sample Vm = 5.91cm ³ , M = 49.9993g ρm = 8.46g/cm ^3rd sample Vm = 7.80cm ³ , M = 17.3550g ρm = 2.23g/cm ³ Sample chip Vm = 15.46cm ³ , M = 19.2774g ρm = 1.25g/cm ^3Example 9 The sample chip used in Example 8 was a hollow glass bulb with air sealed. It is something. In Example 9, the volume of air collected and sealed inside the hollow glass bulb of sample 1 was measured. The glass of sample 1 was manufactured from the same material as that of sample 3, and had a density of 2.23 g/cm ³ . The mass of the glass part of the sample is 19.2673g. Therefore, the volume of the glass part of the hollow glass bulb used as a container is 19.2673÷2.23=8.64cm ³ . Example 8
Since the total volume of the sample was measured to be 15.50 cm ³ using the method described above, the volume of trapped air inside the hollow glass bulb was 15.50 cm3.
=8.64= ^6.78cm3 . The density of sealed air is (19.2774−
19.2673)÷． 78=0.00147g/ ^cm3 . [Effects of the Invention] The present invention uses a gas density balance or a gas specific gravity balance and a solid balance, so the measurement operation is simple, and since the measurement is performed in a gas, the sample may be solid, liquid, or gas. The present invention provides an excellent volume measurement method and volume measurement device that is versatile enough to be applicable to any sample that exhibits a fixed volume in the atmosphere, and capable of high-accuracy, rapid measurement. Furthermore, according to the present invention, the "true mass" shown in vacuum can be easily determined. Since this value is usually not easily determined, the apparent mass measured in the atmosphere is commonly used as the mass. In the measurement method, buoyancy is corrected using a simple approximation formula (Note), or measurements that require accuracy are measured using a vacuum balance. Furthermore, a great effect of the present invention is that since volume and mass are determined simultaneously, density, which is an important physical property value, can be calculated immediately with high precision. (Note) Science Chronology Mono 17 P.431 (1985) Banyu Encyclopedia Volume 16 P.495 (1976) Listed in Shogakukan, etc.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention using an isoblast balance and a gas density balance or a gas specific gravity balance. Figure 2 is a lever balance (unequal ratio balance)
FIG. 2 is a schematic diagram showing an embodiment of the present invention using a gas density balance or a gas specific gravity balance. 1... Equal rod balance, 2... Gas density balance or gas specific gravity balance, 3... Sample to be measured or standard sample, 4... Weight, 5... Weight equivalent to the mass of the sample to be measured, 6... Minute Change measurement unit, 7... Sealed container, 8... Ventilation pipe for gas replacement, 9... Balance weight, 10... Balance weight, 11... Lever balance (unequal ratio balance), 12... fulcrum.

Claims (1)

[Scope of Claims] 1. Change the gas density in a sealed container containing a balance, and change the amount of (a) the mass or weight of a sample to be measured in the sealed container, and (b) the amount of change in the gas density to be measured. A volume measurement method characterized by determining the volume of a sample to be measured by measuring the mass or amount of change in weight of the sample and (c) the amount of change in gas density. 2. The method according to claim 1, wherein a gas density balance or a gas specific gravity balance is used to measure the gas density. 3 One or two gases that do not react with the sample to be measured
The method according to claim 1 or 2, wherein more than one species is used. 4. The balance is (a) a balance capable of measuring the mass or weight of the sample to be measured and the gas density or gas specific gravity in a sealed container, or (b) a balance capable of measuring the mass or weight of the sample to be measured. , a balance for measuring gas density or gas specific gravity in a sealed container, and the balance (a) or (b) and the (a)
or (b) a volume measuring device consisting of a container containing the balance in a sealable manner.