Some factors affecting pore size in the synthesis of rigid polymer monoliths: Theory and its applicability

The investigation included experiments in which factors affecting the reliability of the nylon bag method were studied. The possibility of applying the feed protein degradabilities to practical feeding conditions was also examined. In the experiments concerning reliability, such factors as bag porosity, sample weight, sample treatment, washing procedure, diets, and differences between animals and incubation days were studied. The feed protein degradabilities were also determined by using as incubation periods the ruminal retention times for particulate matter of different feeds, evaluated as a function of DM intake/100 kg liveweight in different diets. A nylon bag, with a pore size of 40 µm and internal dimensions of 6 X 12 cm was selected for the degradability determinations. The sample weight used in incubations was 57 —60 mg DM/cm2. In the determination of feed protein degradability, when sheep are used as experimental animals, it is recommended that for routine determinations only one animal be used, analyzing the contents of two bags for each incubation period during two successive days. A control sample of which degradability is determined in advance in many sheep, should be used in all incubations in order to control the digestive processes in the rumen of the experimental sheep. The actual degradabilities analyzed by the bag method are applicable in practise, if they are determined using animals at similar feeding levels and on diets similar to those prevailing under the conditions in which the degradabilities are going to be used.

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Effect of Biomass-Based Catalyst in Walnut Shell/Polypropylene to BTX

Fine Chemical Engineering ◽

10.37256/fce.3120221057 ◽

2021 ◽

pp. 11-28

Author(s):

Yanan Guo ◽

Xin Pan ◽

Qingjiao Zhu ◽

Jingjing Ma ◽

Qingjie Guo

Keyword(s):

Pore Size ◽

Catalytic Effect ◽

Cycling Performance ◽

Cycle Performance ◽

Walnut Shell ◽

Mass Yield ◽

Key Factors ◽

Factors Affecting ◽

Benzene Toluene ◽

Catalyst Carriers

Four biomass-based catalyst carriers with different pore structures were prepared by using a carbonization-activation method, followed by employment in the copyrolysis of Walnut Shell/Polypropylene (WNS/PP) to produce Benzene, Toluene and Xylene (BTX). Ten cycles were performed in each copyrolysis test in a bench-scaled tube furnace to determine the suitable pore size of the catalyst and excellent cycling performance for BTX production. In addition, Zn, Ni, and Ce were loaded with the selected catalyst carriers to synthesize the most suitable biomass-based catalyst. Results showed that the pore size and active center of the catalyst were the key factors affecting the WNS/PP catalytic copyrolysis. Biomass-based carrier with a pore size in the range of 0.55-1.2 nm was the most suitable to produce BTX in the optimal 10 cycle performance; it realized a relative BTX content of 9-20 area%, and a BTX mass yield of 23-67 mg/(graw) in the liquid-phase products from the WNS/PP copyrolysis. A catalyst loaded with 10 wt% Zn possessed the best catalytic effect with a relative BTX content of 39.49 area%, and a BTX yield of 111.13 mg/(graw)

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Electrochromatography in Microchips: Reversed-Phase Separation of Peptides and Amino Acids Using Photopatterned Rigid Polymer Monoliths

Analytical Chemistry ◽

10.1021/ac011077o ◽

2002 ◽

Vol 74 (4) ◽

pp. 784-789 ◽

Cited By ~ 142

Author(s):

Daniel J. Throckmorton ◽

Timothy J. Shepodd ◽

Anup K. Singh

Keyword(s):

Amino Acids ◽

Phase Separation ◽

Reversed Phase ◽

Polymer Monoliths ◽

Rigid Polymer

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An experimental study on change of gas permeability depending on pore structures in three species (hinoki, Douglas fir, and hemlock) of softwood

Journal of Wood Science ◽

10.1186/s10086-020-01925-9 ◽

2020 ◽

Vol 66 (1) ◽

Author(s):

Eun-Suk Jang ◽

Jee-Hoon Yuk ◽

Chun-Won Kang

Keyword(s):

Pore Structure ◽

Pore Size ◽

Capillary Flow ◽

Gas Permeability ◽

Douglas Fir ◽

International Union ◽

Factors Affecting ◽

Novel Method ◽

Significant Factors

Abstract The purpose of this study is to analyze the pore structure for the heartwood, intermediate wood, and sapwood sections in three species of softwood (hinoki, Douglas fir, and hemlock) and to investigate the correlation of gas permeability depending on pore structure. For this study, gas permeability and pore size were measured by capillary flow porometry, and classification of a novel method was performed to determine the type of pores (through pores, blind pores, and closed pores) based on International Union of Pure and Applied Chemistry (IUPAC). Gas permeability, through pore porosity, and pore size increased from heartwood to sapwood. The results of multiple regression analysis showed that through pore porosity, mean pore size, and bulk density were significant factors affecting gas permeability.

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Effective factors on thermal conductivity of stochastic structures open cell metal foams

Mechanics & Industry ◽

10.1051/meca/2020028 ◽

2020 ◽

Vol 21 (4) ◽

pp. 410

Author(s):

Milad Saljooghi ◽

Abbas Raisi ◽

Amir Farahbakhsh

Keyword(s):

Thermal Conductivity ◽

Pore Size ◽

Shape Factor ◽

Physical Property ◽

Metal Foams ◽

Primary Role ◽

Open Cell ◽

Factors Affecting ◽

Pressure Parameter ◽

Experimental Approaches

Effective thermal conductivity (ETC) is a considerable thermo-physical property in design, manufacturing, and usage of multifunctional equipment that benefit cellular structures such as open-cell metal foams. An accurate understanding of key parameters effecting on ETC is classified by: Analytical, Numerical and Experimental approaches. In this study, a comprehensive investigation based on mentioned approaches is presented and a comparison between various factors affecting ETC including porosity, pore size, temperature, pressure and shape factor is made. Porosity and pore size, as main morphological features of open-cell metal foams, indicate structural characterization of them. Increase of porosity and pore size resulted decrease of ETC. The temperature effects on ETC in case of temperatures lower than 250 °C is ignorable although for temperature higher than 500 °C with change of heat transfer mechanism temperature plays a primary role in determining ETC. Few studies have been made on pressure parameter that illustrated its effect on ETC is insignificant. Multiple manufacturing methods produce different topological structures so; the influence of shape factor on ETC requires more efforts to reach a better understanding. Finally, applicable techniques for measuring ETC are briefly discussed.

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Preparation of microfiltration ceramic membranes

Proceedings of the National Academy of Sciences of Belarus Chemical Series ◽

10.29235/1561-8331-2021-57-1-25-32 ◽

2021 ◽

Vol 57 (1) ◽

pp. 25-32

Author(s):

A. I. Ivanets

Keyword(s):

Tensile Strength ◽

Pore Size ◽

Average Pore Size ◽

Ceramic Membranes ◽

Porous Ceramics ◽

Optimal Conditions ◽

Natural Quartz ◽

Average Pore ◽

Factors Affecting ◽

Water Capacity

The main factors affecting the physicochemical properties of microfiltration ceramic membranes based on natural quartz sand were studied. It was found that samples of large-porous ceramics with a content of 11.0 wt. % of the aluminosilicate binder and 10.0 wt. % of the burning additive are characterized by average pore size of 22±3.02 µm, water capacity of 54±5.0 m3/(h×m2×bar), and tensile strength of 9.0±0.6 bar. The optimal conditions for membrane layers coating were determined, which allowed obtaining microfiltration ceramic membranes with average pore size of 2.3±0.2 µm, water capacity of 26±1.0 m3/(h×m2×bar) and tensile strength of 6.5±0.3 bar.

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