A Simple Method for Prediction of Gas Permeability of Polymers from Their Molecular Structure

The intricate relationship between molecular structure and function is a common theme in molecular biology. Visualizing the structure of biological macromolecules through imaging is therefore useful in understanding their varied biological roles. The process is often complex; imaging in a high voltage Transmission Electron Microscope (TEM) involves extensive staining and freezing. The aim of this experiment was to image DNA easily in a close to natural environment in a simple microscope. Samples were imaged using a Leo (Zeiss) 1550 Scanning Electron Microscope (SEM) with a Schottky field emitter in the 15-30kV range to reduce radiation damage. After imaging off-the-shelf DNA, two more DNA samples were dialyzed with RbCl and NaCl and imaged to elucidate what made the DNA visible.

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Difunctional chemosensor for Cu(ii) and Zn(ii) based on Schiff base modified anthryl derivative with aggregation-induced emission enhancement and piezochromic characteristics

Journal of Materials Chemistry C ◽

10.1039/c4tc02616k ◽

2015 ◽

Vol 3 (9) ◽

pp. 1994-2002 ◽

Cited By ~ 53

Author(s):

Mingdi Yang ◽

Yan Zhang ◽

Weiju Zhu ◽

Huizhen Wang ◽

Jing Huang ◽

...

Keyword(s):

Molecular Structure ◽

Schiff Base ◽

Fluorescent Properties ◽

Simple Method ◽

Aggregation Induced Emission ◽

Schiff Base Derivatives ◽

Emission Enhancement

Three new anthryl Schiff base derivatives containing a similar molecular structure were synthesized through a simple method and their fluorescent properties were investigated in detail.

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Development of a simple method for determination of gas permeability resistance of whole chemical protective gloves

Environmental and Occupational Health Practice ◽

10.1539/eohp.2020-0027-oa ◽

2021 ◽

Author(s):

Takamasa Aoki ◽

Satoko Iwasawa ◽

Shinobu Yamamoto ◽

Akito Takeuchi ◽

Shigeru Tanaka ◽

...

Keyword(s):

Gas Permeability ◽

Simple Method ◽

Protective Gloves

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A simple method to calibrate the temperature effect for the calculation of gas permeability

Thermal Science ◽

10.2298/tsci2106605m ◽

2021 ◽

Vol 25 (6 Part B) ◽

pp. 4605-4610

Author(s):

Shi-Jia Ma ◽

Yuan-Jian Lin ◽

Jiang-Feng Liu ◽

Tao Chen ◽

Pei-Lin Wang ◽

...

Keyword(s):

Temperature Effect ◽

Gas Permeability ◽

Ideal Gas ◽

Control Device ◽

Gas Permeation ◽

Simple Method ◽

Experimental Process ◽

Small Temperature Variation ◽

The Ideal

Temperature plays an important role in the gas permeability test. A small temperature variation still exists in the experimental process since the temperature control device cannot strictly maintain a constant temperature. This can further affect the accuracy of the gas permeability. To solve this problem, a simple method based on the ideal gas equation of state is introduced to calibrate the gas pressure variation because of the temperature effect. We verified the calibration results through sever?al examples, and the results proved the feasibility and effectiveness of the method. In particular, this method is particularly effective for low permeability materials in long-term gas permeation tests.

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Special features of the molecular structure and gas permeability of hollow polypropylene fibres

Polymer Science U S S R ◽

10.1016/0032-3950(89)90016-6 ◽

1989 ◽

Vol 31 (8) ◽

pp. 1825-1832

Author(s):

V.G. Andreyev ◽

A.Sh. Goikhman ◽

G.A. Budnitskii

Keyword(s):

Molecular Structure ◽

Gas Permeability ◽

Polypropylene Fibres

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Molecular Structure of the Outermost Cell Wall Component of Spirillum Serpens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079218 ◽

1977 ◽

Vol 35 ◽

pp. 342-343

Author(s):

Wah Chiu ◽

David Grano

Keyword(s):

Molecular Structure ◽

Cell Wall ◽

Outer Membrane ◽

Gel Electrophoresis ◽

Electron Microscopic Examination ◽

Electron Microscopic ◽

Cell Wall Component ◽

Protein Components ◽

Exposure Technique ◽

Structural Aspects

The periodic structure external to the outer membrane of Spirillum serpens VHA has been isolated by similar procedures to those used by Buckmire and Murray (1). From SDS gel electrophoresis, we have found that the isolated fragments contain several protein components, and that the crystalline structure is composed of a glycoprotein component with a molecular weight of ∽ 140,000 daltons (2). Under an electron microscopic examination, we have visualized the hexagonally-packed glycoprotein subunits, as well as the bilayer profile of the outer membrane. In this paper, we will discuss some structural aspects of the crystalline glycoproteins, based on computer-reconstructed images of the external cell wall fragments.The specimens were prepared for electron microscopy in two ways: negatively stained with 1% PTA, and maintained in a frozen-hydrated state (3). The micrographs were taken with a JEM-100B electron microscope with a field emission gun. The minimum exposure technique was essential for imaging the frozen- hydrated specimens.

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A simple way for producing holographic filters suitable for image improvement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108271 ◽

1978 ◽

Vol 36 (1) ◽

pp. 226-227

Author(s):

K.-H. Herrmann ◽

E. Reuber ◽

P. Schiske

Keyword(s):

Transfer Functions ◽

Diffraction Order ◽

Lateral Position ◽

Simple Method ◽

Spatial Frequencies ◽

Resolution Electron ◽

Wiener Filters ◽

Image Improvement ◽

Optical Reconstruction ◽

Set Up

Aposteriori deblurring of high resolution electron micrographs of weak phase objects can be performed by holographic filters [1,2] which are arranged in the Fourier domain of a light-optical reconstruction set-up. According to the diffraction efficiency and the lateral position of the grating structure, the filters permit adjustment of the amplitudes and phases of the spatial frequencies in the image which is obtained in the first diffraction order.In the case of bright field imaging with axial illumination, the Contrast Transfer Functions (CTF) are oscillating, but real. For different imageforming conditions and several signal-to-noise ratios an extensive set of Wiener-filters should be available. A simple method of producing such filters by only photographic and mechanical means will be described here.A transparent master grating with 6.25 lines/mm and 160 mm diameter was produced by a high precision computer plotter. It is photographed through a rotating mask, plotted by a standard plotter.

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