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Experimental investigation of an adjustable ejector for CO_2 heat pump water heaters

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第11期10卷 1678-1682页

作者： guang-ming CHEN li-xia liANG li-ming TANG Xiao-xiao XU Zhi-jiang ZHU Qi CHEN State Key Laboratory of Clean Energy Utilization Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

An adjustable ejector expansion device for a CO2 heat pump water heater (HPWP) is proposed to improve the system performance. It has been designed to investigate experimentally the effects of the motive nozzle throat area of the ejector, entrained flow pressure, back pressure and primary flow pressure on the entrainment ratio. Experiments based on different motive nozzle throat areas were conducted and the results of the prototype ejector using CO2 as working fluid are presented. The results show that an adjustable ejector can achieve high performance and work well in a wide range of working conditions.

关键词： Adjustable elector System nerformance CO2 heat oumo water heater (HPWH) Entrainment ratio

Effect of Heat Treatment on Microstructure and Property of Al-Sn-Pb Bearing Material

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Journal of Iron and Steel Research International 2006年第2期13卷 73-76页

作者： XU guang-ming li Bao-mian CUI Jian-zhong Key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University Shenyang 110004 Liaoning China

AlSn8Pb2Si2.5Cu0.8Cr0.2 is a bush material with high hardness, and the main elements tin and plumbum mainly exist along the grain boundary, resulting in bad plasticity and confectioning. It is found that the continuous tin and lead distributing along grain boundary are broken by cold-rolling, and their shape is spheroidized and uniform through annealing at constant temperature. The continuous precipitated phase composed of tin and lead doesn＇t exist along grain boundary. The properties of bush material are greatly increased.

关键词： bush material cold-rolling annealing spheroidization

Interfacial Microstructure of Al-Sn-Pb Alloy/Steel During liquid-Solid Bonding Rolling

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Journal of Iron and Steel Research International 2006年第4期13卷 40-43页

作者： XU guang-ming li Bao-mian CUI Jian-zhong Key Laboratory of Electromagnetic Processing of Materials Northeastern UniversityShenyang 110004 Liaoning China

Studies were conducted on the interfacial microstructure of a steel/liquid aluminium and its evolution during the bonding rolling process. The effects of wetting time and deformation on the diffusion layer and on the bonding strength were examined. By means of electron microscopy and electron probe analysis, it was found that the diffusion layer is mainly composed of FeAI3. For a steel temperature of 250℃ and an aluminium temperature of 850 ~C, the diffusion layer was formed within 3 s, and the shear strength of the samples increased after 8 to 14 s. Although the interface was not damaged, it was deformed notably. For an aluminium temperature of 750℃ and a wetting time of 11 to 17 s, the shear strength of the interface remained high, but the interface was obviously broken during rolling, leading to reduced bonding strength.

关键词： liquid-solid bonding rolling wetness diffusion layers interracial strength

NUMERICAL SIMULATION OF 2D HORIZONTAL COOliNG WATER DISCHARGE IN GENERAliZED CURVIliNEAR COORDINATE

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Journal of Hydrodynamics 2006年第1期18卷 91-96页

作者： XIE Zuo-tao ZHANG Xiao-feng TAN guang-ming YANG Fang-li State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072 China

2D horizontal model is one of the major mathematical methods for the research on cooling water discharge from the power plant. In this paper, the shallow water equations are transformed under the generalized curvilinear coordinate system and the elliptic differential equations are used to generate curvilinear grids, so a model in generalized curviline ar coordinate is presented to simulate 2D horizontal cooling water, Governing equations of the model are discretized by finite volume method, and non-staggered grids and SIMPLE algorithm are introduced to simplify the program during the discretization. This model is used to simulate the movement of cooling water in a simplified meandering channel and a natural channel, calculating results indicate this model can correctly reflect the movement rules of cooling water, which verifies the model can be applied in engineering practice.

关键词： cooling water generalized curvilinear coordinate non-staggered grids numerical simulation SIMPLE algorithm

Alcohols＇ Classification by Infrared Spectra Segment Based on Support Vector Machines

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Chinese Chemical Letters 2006年第7期17卷 929-932页

作者： Wei XIE Fu Sheng NIE Meng Long li guang ming li Min Chun LU College of Chemistry Sichuan University Chengdu 610064

This paper studies various classifiers to identify primary, secondary or tertiary alcohols by using segmental spectra and their combinations to support vector machines （SVMs）. The results showed that the O-H in-plane bending absorption contributed most to identification their substitute. This conclusion disagrees with related known research results.

关键词： Infrared spectra alcohols support vector machine information extraction.

A Potential Degree Sequence Problem of the Loebl-Komlós-Sós Conjecture

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Acta Mathematicae Applicatae Sinica 2024年

作者： guang-ming li Jian-hua YIN School of Mathematics and Statistics Hainan University

A non-increasing sequenceπ=(d1,..., dn) of nonnegative integers is said to be a graphic sequence if it is realizable by a simple graph G on n vertices. In this case, G is referred to as a realization ofπ. In terms of graphic sequences, the Loebl-Komlós-Sós conjecture states that for any integers k and n, if π=(d1,..., dn)is a graphic sequence with d「n/2」≥k, then every realization ofπcontains all trees with k edges as *** problem can be viewed as a forcible degree sequence problem. In this paper, we consider a potential degree sequence problem of the Loebl-Komlós-Sós conjecture, that is, we prove that for any integers k and n, ifπ=(d1,..., dn) is a graphic sequence with d「n/2」≥k, then there is a realization ofπcontaining all trees with k edges as subgraphs.

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liquid crystal character controlled by complementary discotic molecules mixtures： Columnar stacking type and mesophase temperature range

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Chinese Chemical Letters 2016年第3期27卷 475-480页

作者： Yan li ming-guang li Ya-Jun Su Jian-Gang liu Yan-Chun Han Shi-Jun Zheng li-Xiang Wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of the Chinese Academy of Sciences Beijing 100049 China School of Materials Science and Engineering Zhengzhou University Zhengzhou 450052 China

In this work, the mesophase properties were tuned via mixing two discotic molecules with structural complementarity. Compared with the liquid crystalline hexakis（n-hexyloxy）triphenylene（H6TP）materials（columnar hexagonal phase from 53 ℃ to 91 ℃）, mesophase types as well as phase transition temperatures varied with the introduction of crystalline hexaazatriphenylene derivative（PBH）molecules. The introduction of less than 33% amount of PBH disrupted the columnar hexagonal phase formed by H6 TP remarkably, followed by the decreased clearing temperatures of liquid crystals. As the PBH amount was further increased, the destroyed columnar hexagonal phase was turned into the columnar rectangular phase, in which H6 TP and PBH molecules together formed the columnar mesophase. The formation of new mesophase contributed to the enlarged mesophase temperature（from44 ℃ to 144 ℃）. We speculated that the alkyl chains interaction induced by the PBH component competed with the strong p–p stacking between H6 TP molecules, thus altering the liquid crystalline properties including mesophase types and phase transition temperatures.

关键词： Alkyl chains packing Mesophase type liquid crystals Phase transitions Mixture

Efficient C_(2)-Symmetric Chiral Schiff Bases for Lanthanide-catalyzed Asymmetric Hydrogenation of Acetophenone

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Chinese Chemical Letters 2006年第10期17卷 1297-1300页

作者： Peng Fei YAN Wen Bin SUN guang ming li Chun Hong NIE Zheng Yu YUE School of Chemistry and Materials Science Heilongjiang University Harbin 150080

An array of C2-symmetric chiral Schiff bases of substituted salicylaldehyde （1R, 2R）-1, 2-cyclohexanediamine and （R）-（＋）-2, 2＇-diamino-1, 1＇-binaphthalene, incorporated with lanthanide complexes, have been applied as catalysts for asymmetric hydrogenation of acetophenone for the first time. Highly enantioselective product with 90% enantiomeric excess （e.e.） was obtained when the catalyst, hybridized by the bulky electron-donating 3, 5-di-tert-butyl substituted Schiff base （2） and SmCl3.4THF, was employed.

关键词： Chiral Schiff base lanthanide (HI) complexes asymmetric hydrogenation acetophenone 2-propanol.

Mechanisms of trichostatin A inhibiting AGS proliferation and identification of lysine-acetylated proteins

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World Journal of Gastroenterology 2013年第21期19卷 3226-3240页

作者： Yu-Gang Wang Na Wang guang-ming li Wen-li Fang Jue Wei Jia-li Ma Ting Wang Min Shi Department of Gastroenterology Shanghai Changning Central Hospital Department of Gastroenterology Xinhua HospitalShanghai Second Medical University

AIM: To explore the effect of lysine acetylation in related proteins on regulation of the proliferation of gastric cancer cells, and determine the lysine-acetylated proteins and the acetylated modified sites in AGS gastric cancer cells. METHODS: The CCK-8 experiment and flow cytometry were used to observe the changes in proliferation and cycle of AGS cells treated with trichostatin A (TSA). Real time polymerase chain reaction and Western blotting were used to observe expression changes in p21, p53, Bax, Bcl-2, CDK2, and CyclinD1 in gastric cancer cells exposed to TSA. Cytoplasmic proteins in gastric cancer cells before and after TSA treatment were immunoprecipitated with anti-acetylated lysine antibodies, separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis gel and silver-stained to detect the proteins by mass spectrometry after removal of the gel. The acetylated proteins in AGS cells were enriched with lysine-acetylated antibodies, and a high-resolution mass spectrometer was used to detect the acetylated proteins and modified sites. RESULTS: TSA significantly inhibited AGS cell proliferation, and promoted cell apoptosis, leading to AGS cell cycle arrest in G0/G1 and G2/M phases, especially G0/G1 phase. p21, p53 and Bax gene expression levels in AGS cells were increased with TSA treatment duration; Bcl-2, CDK2, and CyclinD1 gene expression levels were decreased with TSA treatment duration. Two unknown protein bands, 72 kDa (before exposure to TSA) and 28 kDa (after exposure to TSA), were identified by silver-staining after immunoprecipitation of AGS cells with the lysine-acetylated monoclonal antibodies. Mass spectrometry showed that the 72 kDa protein band may be PKM2 and the 28 kDa protein band may be ATP5O. The acetylated proteins and modified sites in AGS cells were determined. CONCLUSION: TSA can inhibit gastric cancer cell proliferation, which possibly activated signaling pathways in a variety of tumor-associated factors. ATP5O was obvious

关键词： Trichostatin A Acetylation modification Gastric cancer Mass spectrometry ATP5O PKM2