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Advancing optothermal manipulation:decoupling temperature and flow fields in quasi-isothermal microscale streaming

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Light(Science & Applications) 2023年第9期12卷 1713-1714页

作者： Youngsun Kim Yuebing Zheng Materials Science and Engineering Program and Texas Materials Institute The University of Texas at AustinAustinTX78712USA Walker Department of Mechanical Engineering The University of Texas at AustinAustinTX78712USA

By decoupling temperature and flow fields through symmetry-correlated laser scan sequences,ISO-FLUCS enables quasi-isothermal optofluidic microscale streaming.This technique offers precise control over fluid manipulat... 详细信息

关键词： thermal isothermal flow

isothermal Crystallization of iPP in Environment-friendly Diluents:Effect of Binary Diluents and Crystallization Temperature on Crystallization Kinetics

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Chinese Journal of Polymer Science 2019年第6期37卷 617-626页

作者： Yu-Jie Wang Su-Ying Yan Zhi-Ping Zhao Zhen-Yu Xi School of Chemistry and Chemical Engineering Beijing Institute of Technology Environmental Protection Research Institute Beijing Research Institute of Chemical IndustrySINOPEC

The growing demand for non-toxic solvents for membrane preparation has motivated the studies for green and sustainable alternatives of solvents. The effect of droplet isothermal growth within the liquid-liquid phase separation region on isothermal spherulitic growth rate of isotactic polypropylene(iPP) was investigated. The results showed that the droplets grew up at a rate of 0.0172 μm·s^(-1). The larger droplets slowed down the isothermal spherulitic growth rate of iPP. Higher mass ratio of carnauba wax(Cwax)/soybean oil(SO)resulted in faster droplet growth due to weak interaction with polymers. The isothermal crystallization behaviors of iPP in environmentfriendly binary diluents consisting of Cwax and SO mixture were further investigated experimentally using polarized optical microscopy.It was demonstrated that the isothermal spherulitic growth rate of iPP in diluents decreased nonlinearly with the increasing crystallization temperature. Compared with virgin iPP, isothermal spherulitic growth rate of iPP in SO diluent was significantly slowed down. The spherulitic growth was further retarded after the addition of Cwax in mixed diluents, resulting in a lower crystallization rate than that in SO. Moreover, the crystal form of iPP membranes was found to be α type through the characterization of small angle X-ray scattering and wide angle X-ray diffraction.

关键词： Isotactic polypropylene Carnauba wax isothermal crystallization kinetics PP membrane

isothermal reduction kinetics of Panzhihua ilmenite concentrate under 30vol% CO–70vol% N2 atmosphere

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International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 240-248页

作者： Ying-yi Zhang Wei Lü Xue-wei Lü Sheng-ping Li Chen-guang Bai Bing Song Ke-xi Han College of Materials Science and Engineering Chongqing University Chongqing 400044 China Panzhihua Iron and Steel Research Institute Panzhihua 617000 China

The reduction of ilmenite concentrate in 30vol% CO–70vol% N_2 atmosphere was characterized by thermogravimetric and differential thermogravimetric(TG–DTG) analysis methods at temperatures from 1073 to 1223 K.The isothermal reduction results show that the reduction process comprised two stages;the corresponding apparent activation energy was obtained by the iso-conversional and model-fitting methods.For the first stage,the effect of temperature on the conversion degree was not obvious,the phase boundary chemical reaction was the controlling step,with an apparent activation energy of 15.55–40.71 k J·mol^(–1).For the second stage,when the temperatures was greater than 1123 K,the reaction rate and the conversion degree increased sharply with increasing temperature,and random nucleation and subsequent growth were the controlling steps,with an apparent activation energy ranging from 182.33 to 195.95 k J·mol^(–1).For the whole reduction process,the average activation energy and pre-exponential factor were 98.94^(–1)18.33 k J·mol^(–1) and 1.820^(–1).816 min^(–1),respectively.

关键词： ilmenite isothermal reduction kinetics carbon monoxide

isothermal PRECISION FORGING PROCESS OF ALUMINUM ALLOY CYLINDRICAL HOUSING

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中国有色金属学会会刊：英文版 1997年第3期7卷 124-127页

作者： Wang, Z Xue, KM Shan, DB Xu, FC Lu, Y HARBIN INST TECHNOL SCH MAT SCI & ENGNHARBIN 150001PEOPLES R CHINA

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ＩＳＯＴＨＥＲＭＡＬＰＲＥＣＩＳＩＯＮＦＯＲＧＩＮＧＰＲＯＣＥＳＳＯＦＡＬＵＭＩＮＵＭＡＬＬＯＹＣＹＬＩＮＤＲＩＣＡＬＨＯＵＳＩＮＧ①ＷａｎｇＺｈｅｎ，ＸｕｅＫｅｍｉｎ，ＳｈａｎＤｅｂｉｎ，ＸｕＦｕｃｈａｎｇ，ＬｕＹａｎＳｃｈｏｏｌｏｆＭａｔｅｒｉａ...

关键词： aluminum alloy isothermal precision forging assembled die heating range

The kinetic of mass loss of grades A and B of melted TNT by isothermal and non-isothermal gravimetric methods

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Defence Technology（防务技术） 2018年第2期14卷 126-131页

作者： Hamid Reza Pouretedal Sajjad Damiri Parvaneh Nosrati Ehsan Forati Ghaemi Faculty of Applied Chemistry Malek-ashtar University of Technology

The kintic and activation energy of mass loss of two grades of melted TNT explosive, grade A and grade B, with freezing points of 80.57 and 78.15 ℃, respectively, were studied by isothermal and nonisothermal gravimetric methods. In isothermal method, the mass loss of samples in containers of glass and aluminum was followed in temperatures of 80, 90 and 100 ℃. The kinetic of the mass loss of the samples in the aluminum container was higher than the kinetic of it in the glass container that can be related to the effects of heat transfer and catalytic of aluminm metal. Also, the presence of impurities in grade B was due to increasing of kinetic of mass loss of it versus grade A. The non-isothermal curves were obtained in range of 30-330 ℃ at heating rates of 10,15 and 20 ℃·min^(-1).The TG/DTG data were used for determination of activation energy(E_a) of mass loss of TNT samples upon degradation by using Ozawa, Kissinger, Ozawa-Flynn-Wall(OFW) and Kissinger-Akahira-Sunose(KAS) methods as model free methods. The activation energies of grades of A and B of TNT was obtained 99-120 and 66-70 kJ mol^(-1)respectively. The lower values of activation energy of the degradation reaction of grade B confirm the effect of impurities in the kinetics of mass loss of this grade.

关键词： TNT isothermal Non-isothermal Kinetic Mass loss

Rapid identification of Dendrobium officinale using Loop-Mediated isothermal Amplification (LAMP) method

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Chinese Journal of Natural Medicines 2019年第5期17卷 337-345页

作者： YANG Lu WU Wen-Ru ZHOU Hua LAI Hui-Li FU Fei School of Pharmaceutical Sciences Guangzhou University of Chinese Medicine Faculty of Chinese Medicine Macao University of Science and Technology State Key Laboratory of Quality Research in Chinese Medicine Macao University of Science and Technology School of Nursing Guangdong Food and Drug Vocational College

Dendrobium officinale is not only an ornamental plant, but also a valuable medicinal herb that is widely used in traditional Chinese medicine. However, distinguishing D. officinale from other Dendrobium species is usually a difficult task. In this study,we developed a rapid identification protocol for D. officinale using the loop-mediated isothermal amplification(LAMP) method. A set of primers were specifically designed to detect a modified internal transcribed spacer region of D. officinale at 65 ℃ within 40 min after adding SYBR~? Green I, which was used for the detection of D. officinale. Unlike commonly used adulterants, reaction mixtures containing D. officinale DNA changed from orange to green, and this color change was easily observed with the naked eye. Thus, this methodology can be used to accurately differentiate D. officinale from other Dendrobium species, is quick as all D. officinale samples were amplified within 40 min, and specific as samples of the adulterants were not amplified. The specificity of this LAMP-based method was confirmed by testing 17 samples of D. officinale and 32 adulterant samples from other Dendrobium species. This LAMP-based rapid identification method does not require expensive equipment or specialized techniques and can be used in field surveys for accurate and fast on-site identification.

关键词： Dendrobium officinale ITS Loop-mediated isothermal amplification Identification

Microstructure evolution of processed Mg-Al-Zn alloy by equal channel angular extrusion in semi-solid isothermal treatment

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Transactions of Nonferrous Metals Society of China 2006年第6期7卷 1313-1319页

作者：姜巨福罗守靖 School of Materials Science and Engineering Harb in Institute of Technology

Microstructure evolution of processed Mg-Al-Zn alloy by equal channel angular extrusion(ECAE)in semi-solid isothermal treatment was investigated.The results show that with increasing semi-solid isothermal treatment temperature,the α phase solid grain size of processed Mg-Al-Zn alloy by ECAE increases firstly due to coarsening of α phase solid grains,then decreases due to melting of α phase solid grains.With the increase of extrusion passes during ECAE,the α phase solid grain size in the following semi-solid isothermal treatment decreases.The α phase solid grain size of processed Mg-Al-Zn alloy by ECAE under route BC is the smallest,while the α phase solid grain size of processed material by ECAE under route A is the largest.The primary mechanism of spheroid formation depends on the melting of recrystallizing boundaries and diffusion of solute atoms in the semi-solid state.

关键词： magnesium alloy Mg-Al-Zn alloy equal channel angular extrusion isothermal treatment semi-solid proce

Kinetics and microstructural modeling of isothermal austenite-to-ferrite transformation in Fe-C-Mn-Si steels

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Journal of Materials Science & Technology 2019年第8期35卷 1753-1766页

作者： S.J.Song W.K.Che J.B.Zhang L.K.Huang S.Y.Duan F.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University

During the multi-stage processing of advanced high-strength steels, the austenite-to-ferrite transformation, generally as a precursor of the formation of other non-equilibrium or metastable structures, has a severe effect on the subsequent phase transformations. Herein, a more flexible kinetic and microstructural predictive modeling for the key austenite-to-ferrite transformation of Fe-C-Mn-Si steels was developed,in combination with the classical nucleation theory, the general mixed-mode growth model based on Gibbs energy balance, the microstructural path method and the kinetic framework for grain boundary nucleation. Adopting a bounded, extended matrix space corresponding to a single ferrite grain, both softimpingement and hard-impingement can be naturally included in the current modeling. Accordingly, this model outputs the ferrite volume fraction, the austenite/ferrite interface area per unit volume, and the average grain size of ferrite, which will serve as the input parameters for modeling the subsequent bainite or martensite transformations. Applying the model, this work successfully predicts the experiment measurement of the isothermal austenite-to-ferrite transformation in Fe-0.17 C-0.91 Mn-1.03 Si(wt%) steel at different temperatures and explains why the final-state average grain size of ferrite has a maximum at the moderate annealing temperature. Effectiveness and advantages of the present model are discussed arising from kinetics and thermodynamics accompanied with nucleation, growth and impingement.

关键词： isothermal austenite-ferrite transformation Kinetics Thermodynamics Microstructural modeling Low-alloy steel

isothermal COMPRESSION AND PHASE TRANSFORMATION OF MONOXIDE TRANSITION ELEMENT COBALT OXiDE(CoO)

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Chinese Science Bulletin 1992年第14期37卷 1162-1166页

作者：熊大和王积方 Institute of Geology Academia Sinica Beijing 100029 PRC Institute of Physics Academia Sinica Beijing 100080 PRC

Ⅰ. INTRODUCTIONThe high pressure phase transformation and magnetic properties of cobalt oxide (CoO) are of considerable interest both theoretically and experimentally.Powder photographs of cobalt oxide at liquid nitrogen temperature and room temperature (20℃) are shown in the X-ray Debye pattern. At ambient temperature the face center cubic cell has a lattice parameter a = 4.2495±0.0005 At low temperature all reflexions

关键词： isothermal compression phase transformation cobalt oxide