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Modelling of resuspension due to fish activity:Mathematical modeling and annular flume experiments

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International Journal of Sediment Research 2017年第3期32卷 421-431页

作者： olya Skulovich Catrina Cofalla Caroline Ganal Holger schttrumpf Avi Ostfeld Faculty of Civil and Environmental Engineering Technion-IIT Institute of Hydraulic Engineering and Water Resources Management RWTH Aachen University Institute for Environmental Research RWTH Aachen University

A spatially averaged numerical model was developed to describe the erosion of cohesive *** with known empirical relations, the model comprises a new formulation for resuspension due to fish activity. Experiments on erosion of natural sediments in the annular flume at Aachen university are used for model calibration. Empirical coefficients were evaluated with genetic algorithms to achieve the best agreement between the model results and the experimental data. The presented model shows sufficient flexibility to account for various sediment properties, including different sediment sources,natural and artificial contaminants, presence or absence of aquatic organisms, and results in an average coefficient of determination, R2=90.5% between the model results and the experimental data. Model validation allows it to be assumed that different contaminants affect bed properties differently. Fish activity plays an essential role in correct resuspension prediction. Further sediment erosion experiments with carefully chosen conditions will allow a more comprehensive model evaluation. The presented model is intended to serve as a building block in the development of a hydraulic-sediment-biota model within the W3-Hydro: Water Quality Event Detection for Urban Water Security and Urban Water Management Based on Hydrotoxicological Investigations project that aims to improve the knowledge concerning bioavailability, transport, fate, and effects of contaminants on the aquatic environment.

关键词： Cohesive sediment Erosion Annular flume Numerical simulation Fish-induced resuspension

Photoresponsive Supramolecular Hydrogel Co-assembled from Fmoc-Phe-OH and 4,4′-Azopyridine for Controllable Dye Release

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Chinese Journal of Polymer Science 2019年第5期37卷 437-443页

作者： Xiao-Qiu Dou Chang-Li Zhao Nabila Mehwish Ping Li Chuan-Liang Feng Holger sch?nherr Physical Chemistry I and Research Center of Micro and Nanochemistry and Engineering (Cμ) Department of Chemistry and BiologyUniversity of Siegen State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong University

Photoresponsive hydrogels have been attractive because they can provide precise spatial and temporal control for molecule release, whereas the conventional preparation of photoresponsive hydrogels generally involves complex chemical synthesis steps or specific conditions which limits their practical applications. Herein, a new photoresponsive hydrogel is facilely prepared via co-assembly of two simple molecules, Fmoc-Phe-OH and Azp, without chemical synthesis. The co-assembly mechanism, morphology, and photoresponsiveness of(Fmoc-Phe-OH)-Azp hydrogel are investigated by circular dichroism(CD), ultraviolet-visible(UV-Vis), fluorescence, ~1 H nuclear magnetic resonance(~1 H-NMR), attenuated total internal reflection Fourier transform Infrared(ATR-FTIR) spectroscopy, and scanning electron microscopy(SEM). Furthermore, the enhanced release of encapsulated sulforhodamine B(SRB) dye molecules can be achieved via UV light irradiation. The enhanced dye release amount can be controlled by manipulating photoirradiation time. This study provides a facile way to prepare photoresponsive hydrogel which holds great potential for controllable drug release.

关键词： Photoresponsive Supromolecular Co-assembly Hydrogel Dye release

Electronic Structure of New Superconducting Perovskite MgCNi3

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Journal of Materials Science & Technology 2004年第2期20卷 203-205页

作者： Li CHEN, Hua LI and Liangmo MEIPhysics and Microelectronic sch.ol, Shandong university, Jinan 250100, China Department of Physics, Linyi Teachers university, Shandong 276005, China Phys. and Microelectron. sch. Shandong Univ. Ji'nan 250100 China Dept. of Phys. Linyi Teachers Univ. Linyi 276005 China

The electronic structures of new superconducting perovskite MgCNi3 and related compounds MgCNi2T (T=Co, Fe, and Cu) have been studied using MS-Xa method. In MgCNi3, the main peak of density of states is located below the Fermi level and dominated by Ni d. From the results of total energy calculations, it was found that the number of Ni valence electron decreases faster for the Fe-doped case than that for the Co-doped case. The valence state of Ni changes from +1.43 in MgCNi2Co to +3.02 in MgCNi2Fe. It was confirmed that Co and Fe dopants in MgCNi3 behave as a source of d-band holes and the suppression of superconductivity occurs faster for the Fe-doped case than that for the Co-doped case. In order to explain the fact that Co and Fe dopants in MgCNi3 behave as a source of d-band holes rather than magnetic scattering centers that quench superconductivity, we have also investigated the effects of electron (Cu) doping on the superconductivity and found that both electron (Cu) doping and hole (Co, Fe) doping quench superconductivity exist. Comparing with the hole (Co) doping, there was no much difference between Cu and Co doping. This suggests that Co and Fe doping do not act as magnetic impurity.

关键词： Electronic structure Superconductivity Density of states

Thermophysical properties of the Ni-based alloy Nimonic 80A up to 2400 K

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Rare Metals 2006年第5期25卷 529-531页

作者： B.Wilthan R.Tanzer W.schützenhfer G.Pottlacher Institute of Experimental Physics Graz University of TechnologyPetersgasse 168010 GrazAustria Bhler Edelstahl GmbH Mariazellerstrasse 258605 KapfenbergAustria

Nimonic 80A is a nickel-chromium alloy which is strengthened by additions of titanium and aluminium. The alloy is used for high temperature, high strength applications. Wire shaped Nimonic 80A samples are resistively volume heated as part of a fast capacitor discharge circuit. Time resolved measurements with sub-μs resolution of current through the specimen are performed with a Pearson probe, voltage drop across the specimen is measured with knife-edge contacts and ohmic voltage dividers and the radiance temperature of the sample with a pyrometer. These measurements allow to determine heat of fusion as well as heat capacity and electrical resistivity at initial geometry of Nimonic 80A as a function of temperature in the solid and in the liquid phase up to 2400 K.

关键词： thermophysical properties Nimonic 80A resistivity enthalpy heat capacity latent heat

Cytomegalovirus infection in liver transplant recipients

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Hepatobiliary & Pancreatic Diseases International 2002年第1期1卷 30-32页

作者： Jun Fan Wei-Hang Ma Jing Qian Zhi Chen Dong--Sheng Huang Wei-Lin Wang Shu-Sen Zheng From the First Affiliated Hospital, Zhejiang university sch.ol of medicine, Hangzhou 310003, China First Affiliated Hospital Zhejiang University Sch. of Medicine Hangzhou 310003 China

Objective: To explore cytomegalovirus （CMV） infec-tion in recipients of liver transplantation （LT）.Methods: 30 recipients of LT were screened for theappearance of CMV infection by using ELISA to testanti-CMV-Ab from serum samples and using im-munohistochemistry method to test CMV antigen ex-pression and nested-PCR to amplify CMV-DNA fromblood ***: Four of 243 samples taken from 30 recipientscame out positive of anti-CMV IgC; and anti-CMVIgM with a positive rate of 100% and 1.6% respec-tively. 85 samples resulted in CMV antigen expression（35.0%） with the average antigen index being 4.2±3.1/5×10;WBC. Besides, 99 samples were found tobe positive by nested-PCR with a positive rate of40.7%. 61 samples were found to be simultaneously pos-itive in test of CMV antigen and DNA, with a rate of25.1%.Conclusions: Infection of CMV is common in recipi-ents of LT. Simultaneous screening of anti-CMV-Ab, CMV-Ag and CMV-DNA after liver transplanta-tion is very important for early diagnosis of CMV in-fection.

关键词： cytomegalovirus anti-CMV-Ab cytomegalovirus antigen cytomegalovirus DNA liver transplantation

Adiponectin and its receptors in rodent models of fatty liver disease and liver cirrhosis

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World Journal of Gastroenterology 2006年第34期12卷 5490-5494页

作者： Markus Neumeier Claus Hellerbrand Erwin Gbele Roland Buettner Cornelius Bollheimer Johanna Weigert Andreas schffler Thomas S Weiss Monika Lichtenauer Jürgen schlmerich Christa Buechler Department of Internal medicine I University of Regensburg D-93042 Regensburg Germany Department of Surgery Center for Liver Cell Research University of Regensburg Germany

AIM： To determine circulating and hepatic adiponectin in rodents with fatty liver disease or liver cirrhosis and investigate expression of the adiponectin receptors AdipoR1 on the mRNA and protein level and AdipoR2 on the mRNA level. METHODS： Fat fed rats were used as a model for fatty liver disease and bile duct ligation in mice to investigate cirrhotic liver. Expression of AdipoR1 and AdipoR2 mRNA was determined by real time RT-PCR. AdipoR1 protein was analysed by immunoblot. Adiponectin was measured by ELISA. RESULTS： Systemic adiponectin is reduced in fatfed rats but is elevated in mice after bile duct ligation （BDL）. Hepatic adiponectin protein is lower in steatotic liver but not in the liver of BE）L-mice when compared to controls. Adiponectin mRNA was not detected in human liver samples or primary human hepatocytes nor in rat liver but recombinant adiponectin is taken up by isolated hepatocytes in-vitro. AdipoR1 mRNA and AdipoR1 protein levels are similar in the liver tissue of control and fat fed animals whereas AdipoR2 mRNA is induced. AdipoR2 mRNA and AdipoR1 mRNA and protein is suppressed in the liver of BDL-mice. CONCLUSION： Our studies show reduced circulating adiponectin in a rat model of fatty liver disease whereas circulating adiponectin is elevated in a mouse model of cirrhosis and similar findings have been described in humans. Diminished hepatic expression of adiponectin receptors was only found in liver cirrhosis.

关键词： Hepatic steatosis Adiponectin Liver cirrhosis Adiponectin receptor 1 Adiponectin receptor 2

Characteristics of Ni-based ohmic contacts on n-type 4H-SiC using different annealing methods

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Nanotechnology and Precision Engineering 2021年第1期4卷 44-47页

作者： Ziwei Zhou Weiwei He Zhenzhong Zhang Jun Sun Adolf schöner Zedong Zheng Research and Development Department BASiC Semiconductor Ltd.Shenzhen 518000China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China

Nickel is an excellent ohmic-contact metal on *** paper discusses the formation mechanism of nickel ohmic contact on 4HSiC by assessing the electrical properties and microstructural *** high-temperature annealing,the phase of nickel-silicon compound can be observed with X-ray diffraction,and the contact resistance also changes.A comparative experiment was designed to use X-ray diffraction and energy-dispersive spectroscopy to clarify the difference of ohmic-contact material composition and elemental analysis between samples prepared using pulsed laser annealing and rapid thermal *** is found that more Ni2Si and carbon vacancies formed at the interface in the sample prepared using pulsed laser annealing,resulting in a better ohmic-contact characteristic.

关键词： Laser annealing Rapid thermal annealing Ohmic contact Ni 4H-SiC Carbon vacancy

Determination of failure degree of 1.2 kV SiC MOSFETs after short-circuit test using an improved test setup

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Nanotechnology and Precision Engineering 2020年第4期3卷 235-240页

作者： Shen Diao Jun Sun Ziwei Zhou Zhenzhong Zhang Adolf schöner Zedong Zheng Weiwei He Research and Development Department Shenzhen BASiC Semiconductor Ltd.Shenzhen 518000China Dept.Electrical Engineering Tsinghua UniversityBeijing 100084China

Analysis of the short-circuit characteristics of SiC metal-oxide-semiconductor field-effect transistors(MOSFETs)is very important for their practical *** paper studies the SiC MOSFET short-circuit characteristics with an improved test setup under different conditions.A high-current Si insulated gate bipolar transistor is used as a circuit breaker in the test circuit rather than the usual short-circuit test conducted without a circuit *** test platform with a circuit breaker does not influence the calculation results regarding the shortcircuitwithstand time and energy,but the SiCMOSFETwill switch off after failure in a very short *** addition,the degree of failure will be limited and confined to a small area,such that the damage to the chip will be clearly observable,which is significant for short-circuit failure analysis.

关键词： SiC MOSFET Short-circuit test Failure analysis

Application of annexation principle to the study of thermodynamic properties of Ag-Bi-In metallic melts

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Journal of university of Science and Technology Beijing 2003年第1期10卷 18-20页

作者： Jian ZhangMetallurgy sch.ol, university of Science and Technology Beijing, Beijing 100083, China Metall. sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on the measured activities, the phase diagrams and the annexation principle, the calculating models of mass action concentrations for Ag-Bi and Ag-Bi-In melts have been formulated. The calculated results agree with practice and obey the mass action law, showing that the models formulated can reflect the structural characteristics of both melts. Meanwhile, it confirms that annexation principle is applicable to the Ag-Bi-In metallic melts. The melts involving eulectic which give rise to phase separation, and in which activities exhibit positive deviation from Raoult's law is the basic cause of melts transforming from homogeneous to heterogeneous ones.

关键词： the mass action law annexation principle two phase melts activity, mass action concentration