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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 43-53,59页

作者： wang Ya-li SONG mei WEI Yi-fei wang Ying-he wang Xiao-jun School of Electronic Engineering Beijing University of Posts and Telecommunications Chinese Academy of Science Shanghai Institute of Microsystem and Information Technology School of Electronic Engineering Dublin City University

In order to establish a route supporting multi-constrained quality of service（QoS）, increase network throughput and reduce network energy consumption, an improved ant colony-based multi-constrained QoS energy-saving routing algorithm（IAMQER） is proposed. The ant colony algorithm, as one of the available heuristic algorithms, is used to find the optimal route from source node to destination node. The proposed IAMQER algorithm, which is based on the analysis of local node information such as node queue length, node forwarding number of data packets and node residual energy, balances the relationship between the network throughput and the energy consumption, thus improving the performance of network in multi-constrained QoS routing. Simulation results show that this IAMQER algorithm can find the QoS route that reduce average energy consumption and improves network packet delivery ratio under the end-to-end delay and packet loss ratio constraints.

关键词： wireless Ad-hoc networks multi-constrained QoS routing ant colony algorithm energy-saving throughput optimization

Effect of Heat Treatment on Microstructure and Stress Rupture Properties of a Ni–Mo–Cr–Fe Base Corrosion-Resistant Superalloy

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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 116-126页

作者： Tao Liu mei Yang jun-Song wang Jia-Sheng Dong Li wang Lang-Hong Lou Jiangsu University of Technology Harbin Engineering University Institute of Metal Research Chinese Academy of Sciences

The influences of heat treatment and test condition on the microstructure and stress rupture properties of a Ni–Mo–Cr–Fe base corrosion-resistant superalloy have been investigated in this paper. Optical microscope and scanning electron microscope were employed for the microstructure observation, and X-ray diffraction, electron probe micro-analyzer, and transmission electron microscope were used for phase determination. It was found that the grain size increased and the volume fractions of initial M_6C carbides decreased along with the increase in solution treatment temperature. When tested at 650 °C/320 MPa, the stress rupture lives decreased with the increase in solution treatment temperature, but the stress rupture lives increased slightly at first and then decreased for the samples solution heat treated at 1220 °C when tested at 700 °C/240 MPa. The elongations showed the descendent trends under these two conditions. The stress rupture life and elongation for the aged samples all showed a noticeable improvement at 650 °C/320 MPa, but there was no noticeable improvement at 700 °C/240 MPa. The reasons can be attributed to the grain size, test conditions, and the initial and secondary carbides.

关键词： Corrosion-resistant superalloy Heat treatment Stress rupture properties Secondary carbides

Reinforcement of High Impact Polystyrene by Aramid Nanoparticle Fillers Prepared via an In situ Bottom-up Approach

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Chinese Journal of Polymer Science 2024年第8期42卷 1167-1176页

作者： Xiang-jun Gong Zhi-Ping Zhao Chang-mei Sun Ying Zhang Rong-jun Qu Ying wang School of Chemistry and Materials Science Ludong UniversityYantai 264025China

In this work,aramid nanoparticles(ANPs)were prepared in dimethyl formamide(DMF)solution containing high impact polystyrene(HIPS)via a bottom-up *** electron microscopy(TEM)images showed that the obtained ANPs were evenly distributed in the HIPS matrix without any *** composition of the ANPs,i.e.,poly(p-phenyl-p-phenylenediamine)(PPTA),was confirmed by Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and X-ray diffractometer(XRD).The ANP/HIPS composites,obtained after ethanol precipitation,were added to neat HIPS as fillers to fabricate ANP/HIPS composite *** surface roughness and the glass transition temperature(T_g)of the sheets were characterized by atomic force microscope(AFM)and differential scanning calorimetry(DSC),*** with neat HIPS,the mechanical properties of the composite sheet were significantly improved,and the Young's modulus increased from 246.55 MPa to 2025.12 MPa,the tensile strength increased from 3.07 MPa to 29.76 MPa,and the toughness increased from 0.32 N/mm^2 to 3.92 N/mm^2,with an increase rate of 721%,869%and 1125%,***,the thermal stability of the composites improved with the increase in ANP content.

关键词： High impact polystyrene PPTA nanoparticle Reinforce Mechanical property

Caffeine is responsible for the bloodglucose-lowering effects of green tea and Puer tea extractsin BALB/c mice

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Chinese Journal of Natural Medicines 2015年第8期13卷 595-601页

作者： FANG Chong-Ye wang Xuan-jun HUANG Ye-Wei HAO Shu-mei SHENG jun Ministry of Education Key Laboratory of Puer Tea Science at Yunnan Agricultural University Yunnan Research Center for Advanced Tea Processing Department of Pu-erh Tea and Medical Science Hyogo College of Medicine Yunnan University

The present study was designed to determine the effects of Puer tea and green tea on blood glucose level. Male BALB/c mice were administered green tea extract(GTE) or Puer tea extract(PTE), either intragastrically or in their drinking water. The major components of these teas are epigallocatechin gallate(EGCG) and caffeine, respectively. Blood glucose measurement results showed that mice fed intragastrically or mice that drank GTE, PTE or caffeine showed significantly lower blood glucose levels compared to the control group. However, EGCG exhibited no influence on the blood glucose levels. When caffeine was eliminated from the GTE and PTE, the effect on the blood glucose levels was abolished, but the effect was recovered when caffeine was re-introduced into the extracts. Evaluation of hematological and biochemical indices at the time of the greatest caffeine-induced decrease in blood glucose levels showed that the effect of caffeine was specific. Microarray analyses were performed in 3T3-L1 preadipocytes and mature adipocytes treated with 0.1 mg·m L-1 caffeine to identify factors that might be involved in the mechanisms underlying these effects. The results showed that few genes were changed after caffeine treatment in adipocytes, and of them only phospholipid transfer protein(PLTP) may be ralated to blood glucose. In conclusion, this study indicates that caffeine may be the key constituent of tea that decreases blood glucose levels, and it may be used to treat type 2 diabetes.

关键词： Caffeine EGCG Puer tea extract(PTE) Blood glucose Normal mice Type 2 diabetes

2D/2D Heterostructures:Rational Design for Advanced Batteries and Electrocatalysis

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Energy & Environmental Materials 2022年第1期5卷 115-132页

作者： jun mei Ting Liao Ziqi Sun School of Chemistry and Physics Queensland University of Technology2 George StreetBrisbane Qld 4000Australia School of Mechanical Medical and Process Engineering Queensland University of Technology2 George StreetBrisbane Qld 4000Australia Centre for Materials Science Queensland University of Technology2 George StreetBrisbane Qld 4000Australia

Two-dimensional/two-dimensional(2D/2D)heterostructures consisting of two or more 2D building blocks possess intriguing electronic features at the nanosized interfacial regions,endowing the possibility for effectively modulating the confinement,and transport of charge carriers,excitons,photons,phonons,*** bring about a wide range of extraordinary physical,chemical,thermal,and/or mechanical *** rational design and synthesis of 2D/2D heterostructures,electrochemical properties for advanced batteries and electrocatalysis can be well regulated to meet some practical *** this review,a summary on the commonly employed synthetic strategies for 2D/2D heterostructures is first given,followed by a comprehensive review on recent progress for their applications in batteries and various electrocatalysis ***,a critical outlook on the current challenges and promising solutions is presented,which is expected to offer some insightful ideas on the design principles of advanced 2D-based nanomaterials to address the current challenges in sustainable energy storages and green fuel generations.

关键词： 2D heterostructures 2D nanomaterials battery electrocatalysis energy storage

Theoretical Studies on Expressions of Condensed-Phase Photoionization Cross Section

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Communications in Theoretical Physics 2006年第4X期46卷 727-730页

作者： MA Xiao-Guang wang mei-Shan wang De-Hua QU Zhao-jun Department of Physics Yantai Normal University Yantai 264025 China

A set of general expressions for photoionization cross sections of atoms or molecules embedded in a medium and a dielectric influence function are derived based on Maxwell＇s equations and the Beer-Lambert＇s law in this work. The applications are performed for the photoionization process of solid gold both in the Clausius-Mossotti （virtual cavity） model and the Glauber-Lewenstein （real cavity） model firstly. The results show that the present theoretical expressions of photoionization cross section can be used to describe the photoionization process of atoms in condensed matter properly.

关键词： condensed-phase photoionization optical constant dielectric constant

Biosynthesis of 4-hydroxyphenylpyruvic acid from L-tyrosine using recombinant Escherichia coli cells expressing membrane bound L-amino acid deaminase

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Chinese Journal of Chemical Engineering 2018年第2期26卷 380-385页

作者： Huanru Ding Weirui Zhao Changjiang Lu jun Huang Sheng Hu Shanjing Yao Lehe mei Jinbo wang Jiaqi mei School of Biotechnology and Chemical Engineering Ningbo Institute of TechnologyZhejiang UniversityNingbo 315100China Department of Chemical and Biolagical Engineering Zhejiang UniversityHangzhou 310027China School of Biological and Chemical Engineering Zhejiang University of Science and TechnologyHarlgzhou 310023China Department of Chemical Engineering The University of utahSalt Lake City 84102America

4-Hydroxyphenylpyruvic acid （4-HPPA）, a kind of α-keto acid, is an intermediate in the metabolism of tyrosine and has a wide range of application in food, pharmaceutical and chemical industry. Using amino acids as raw material to prod uce the corresponding α-keto acid is thought to be both economic and efficient. Among the enzymes that convert amino acid to α-keto acid, membrane bound L-amino acid deaminase （mL-AAD）, which is anchored to the outer side of the cytomembrane, becomes an ideal enzyme to prepare α-keto acid since there is no cofactors needed and H2O2 production during the reaction. In this study, the mL-AAD from Proteus vulgaris was used to prepare whole-cell catalysts to produce 4-HPPA from L-tyrosine. The secretory efficiency of mL-AAD conducted by its own twin-arginine signal peptide （twin-arginine translocation pathway, Tat） and integrated pelB （the general secretory pathway, Sec）-Tat signal peptide was determined and compared firstly, using two pET systems （pET28a and pET20b）. It was found that the Tat pathway （pET28a-mlaad） resulted in higher cell-associated mL-AAD activity and cell biomass, and was more beneficial to prepare biocatalyst. In addition, expression hosts BI21 （DE3） and 0.05 mmol. L- 1 IPTG were found to be suitable for mL-AAD expression. The reaction conditions for mL-AAD were optimized and 72.72 mmol,L 1 4-HPPA was obtained from 100 mmol.L 1 tyrosine in 10 h under the optimized conditions. This bioprocess, which is more eco-friendly and economical than the traditional chemical synthesis ways, has great potential for industrial application.

关键词： 4-Hydroxyphenylpyruvic acidc-tyrosine Membrane-bound L-amino acid deaminases Biocatalysis Molecular biology Biological engineering

Outcomes of endoscopic sclerotherapy for jejunal varices at the site of choledochojejunostomy (with video): Three case reports

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World Journal of Gastroenterology 2024年第14期30卷 2059-2067页

作者： jun Liu Peng wang Li-mei wang Jing Guo Ning Zhong Department of Gastroenterology Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina

BACKGROUND Hemorrhage associated with varices at the site of choledochojejunostomy is an unusual,difficult to treat,and often fatal manifestation of portal *** far,no treatment guidelines have been *** SUMMARY We reported three patients with jejunal varices at the site of choledochojejun-ostomy managed by endoscopic sclerotherapy with lauromacrogol/α-butyl cyanoacrylate injection at our institution between june 2021 and August *** reviewed all patient records,clinical presentation,endoscopic findings and treatment,outcomes and *** patients who underwent pancre-aticoduodenectomy with a Whipple anastomosis were examined using conven-tional upper gastrointestinal endoscopy for suspected hemorrhage from the afferent jejunal *** with stigmata of recent hemorrhage or active he-morrhage were observed around the choledochojejunostomy site in all three *** injection of lauromacrogol/α-butyl cyanoacrylate was carried out at jejunal varices for all three *** bleeding ceased and patency was observed for 26 and 2 months in two *** one patient with multiorgan failure and internal environment disturbance,rebleeding occurred 1 month after endoscopic sclerotherapy,and despite a second endoscopic sclero-therapy,repeated episodes of bleeding and multiorgan failure resulted in eventual *** We conclude that endoscopic sclerotherapy with lauromacrogol/α-butyl cyanoac-rylate injection can be an easy,effective,safe and low-cost treatment option for jejunal varicose bleeding at the site of choledochojejunostomy.

关键词： Endoscopic sclerotherapy Jejunal varices Choledochojejunostomy Portal vein hypertension Case report

Effect of glycosides of Cistanche on the expression of mitochondrial precursor protein and keratin type Ⅱ cytoskeletal 6A in a rat model of vascular dementia

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Neural Regeneration Research 2017年第7期12卷 1152-1158页

作者： Yan-mei Zhang Wei Wu Wei Ma Fang wang jun Yuan Department of Neurology Inner Mongolia Autonomous Region People's Hospital Hohhot Inner Mongolia Autonomous Region China Department of Brain Center The Second Affiliated Hospital of Wenzhou Medical University Wenzhou Zhejiang Province China First Hospital of Wuhan Wuhan Hubei Province China Jianghan University Wuhan Hubei Province China

Glycosides of Cistanche（GC）is a preparation used extensively for its neuroprotective effect against neurological diseases,but its mechanisms of action remains incompletely ***,we established a bilateral common carotid artery occlusion model of vascular dementia in rats and injected the model rats with a suspension of GC（10 mg/kg/day,intraperitoneally）for 14 consecutive *** showed that GC significantly reduced p-tau and amyloid beta（Aβ）immunoreactivity in the hippocampus of the model *** analysis demonstrated upregulation of mitochondrial precursor protein and downregulation of keratin type II cytoskeletal6A after GC treatment compared with model rats that had received *** blot assay confirmed these *** results suggest that the neuroprotective effect of GC in vascular dementia occurs via the promotion of neuronal cytoskeleton regeneration.

关键词： nerve regeneration vascular dementia glycosides of Cistanche mitochondrial precursor protein keratin type Ⅱ cytoskeletal 6A proteomics neuroprotection neural regeneration

Structure of GdMg(BO_2)_5 Crystal

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Chinese Journal of Structural Chemistry 2006年第6期25卷 709-713页

作者： FAN jun-mei LIN Zhou-Bin ZHANG Li-Zhen wang Guo-Fu State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The title compound GdMg（BO2）s crystallizes in monoclinic, space group P21/n with a = 8.6230（17）, b = 7.5860（15）, c = 9.3777（19） A, β= 93.19（3）°, V = 612.5（2） A3, Z = 4, Mr = 395.61, De= 4.290 g/cm^3,μ = 10.987 mm^-1, F（000） = 724, the final R = 0.0135 and wR= 0.0355 for 1373 observed reflections with I 〉 2σ（I）. The structure consists of BO3 triangles, BO4 tetrahedra, MgO6 distortion octahedra and GdO10 polyhedra. Furthermore, BO3 triangles and BO4 tetrahedra have been verified by infrared spectra. The Gd atoms form infinite zigzag chains along the b axis with the shortest distance of Gd--Gd being 3.958 A. The shorter Gd--Gd will result in a strong interaction between active ions and a large fluorescence concentration quenching effect.

关键词： crystal structure GdMg(BO2)5 crystal