Molecular weight measurement method and molecular weight measurement apparatus

Patent metadata

Field	Value
Publication number	US-2018052085-A1
Application number	US-201615555198-A
Country	US
Kind code	A1
Filing date	Mar 4, 2016
Priority date	Mar 6, 2015
Publication date	Feb 22, 2018
Grant date	—

Abstract

A sample in a gas state to be measured is forced to impinge on a structure in which a change in a characteristic including a mechanical deformation, an optical change, an electric change and a magnetic change is exerted due to the impingement of a gaseous sample, a gasified liquid sample or solid sample to cause at least one of changes in characteristics including a mechanical deformation, an optical change, an electric change and a magnetic change; and the molecular weight of the sample in a gas state is obtained.

First claim

1 . A method of measuring a molecular weight, comprising the steps of:
preparing a structure that causes a change in characteristic including a mechanical deformation, an optical change, an electric change, and a magnetic change by letting a gaseous sample or gasified liquid or solid sample on a surface thereof, causing a change in the characteristic of the structure by letting a sample in a gas state to be measured to imping on the structure, the change in a characteristic being at least one selected from the group consisting of a mechanical deformation, an optical change, an electric change, and a magnetic change; and obtaining a molecular weight of the sample in a gas state based on the amount of the change.

2 . The method of measuring a molecular weight according to claim 1 , wherein the change which occurs in the structure is a mechanical deformation, and the method comprises the steps of deforming the structure by letting the sample in a gas state to be measured to impinge on the structure, and obtaining the molecular weight of the gas based on the amount of the deformation of the structure.

3 . The method of measuring a molecular weight according to claim 2 ,
wherein a drag force F D by the sample in a gas state is calculated based on the amount of the deformation of the structure; and the molecular weight M of the gas is obtained based on the following mathematical formula:

[

Mathematical



Formula



1

]

F
D

=

PV
2



C
D


A

2

RT


M

wherein, in the mathematical formula, R is a gas constant, T is a temperature of the gas, P is a pressure of the gas, V is a relative velocity of the gas, C D is a drag coefficient, and A is a surface area on which the drag force is applied.

4 . The method of measuring a molecular weight according to claim 1 , wherein the sample in a gas state is provided as a jet flow to the structure.

5 . The method of measuring a molecular weight according to claim 1 , wherein the structure is a cantilever.

6 . The method of measuring a molecular weight according to claim 4 , wherein the drag force is provided by the following mathematical formula:

[

Mathematical



Formula



2

]

F
D

=

9


wC
D



LM
3



P
3



Q
4

8


π
4



μ
2



l
4



H
2



R
3



(

3


x
2



M
2



P
2



Q
2

16


π
2



μ
2



l
2



Assignees

• Nat Inst Materials Science

Inventors

• Yoshikawa Genki
• SHIBA Kota

Classifications

• G01N29/36

  Detecting the response signal {, e.g. electronic circuits specially adapted therefor} · CPC title

• G01N2291/0427

  Flexural waves, plate waves, e.g. Lamb waves, tuning fork, cantilever · CPC title

• G01N5/02 Primary

  by absorbing or adsorbing components of a material and determining change of weight of the adsorbent, e.g. determining moisture content {(absorption bulbs B01D53/00)} · CPC title

• G01N9/002

  using variation of the resonant frequency of an element vibrating in contact with the material submitted to analysis (G01N9/34 takes precedence) · CPC title

• G01N11/00

  Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties · CPC title