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Flow Field and Performance of Cross Flow Fans——Experimental and Theoretical Investigations

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Journal of Thermal Science 2003年第3期12卷 234-238页

作者： Martin Gabi simon dornstetter Toni Klemm Institute of Fluid Machinery University of Karlsruhe (TH) D-76128 Karlsruhe GermanyRobert Bosch GmbH D-71701 Schwieberdingen GermanyInstitute of Fluid Machinery University of Karlsruhe (TH) D-76128 Karlsruhe Germany

due to the construction and the operating principle the prediction of performance of Cross Flow Fans (CFF) is difficult and the knowledge about the internal flow regime is limited. To investigate the impact of geometrical parameters on the performance of CFF, experimental investigations, using Particle Imaging Velocimetry (PIV), and CFd calculations were carried out. Some results of PIV measurements and CFd calculations are presented, which give an impression of the internal flow and confirm the numerical calculations.

关键词： fans cross-flow fans computational fluid dynamics particle imaging velocimetry

Hepatitis B Surface Antigen and Hepatitis C Virus Antibodies among drug Users in Burkina Faso

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Advances in Microbiology 2024年第1期14卷 92-104页

作者： Sylvie Zida Kadari Cissé Odette Ky-Zerbo dinanibè Kambiré Serge Théophile Soubeiga simon Tiendrebéogo Fatou Sissoko Issa Sory Célestine Ki-Toé Solange dioma djeneba Zorom Adama Ouédraogo Cedric dimitri Axon Hien Mahamoudou Sanou Seni Kouanda Henri Gautier Ouédraogo Institut de Recherche en Sciences de la Santé Ouagadougou Burkina Faso dé partement de G&eacuteographie Universit&eacute Norbert ZONGO Koudougou Burkina Faso Secré tariat permanent du Conseil national de lutte contre le Sida et les IST (SP/CNLS-IST) Ouagadougou Burkina Faso Initiative Privé e et Communautaire pour la Sant&eacute et la Riposte au VIH/SIDA au Burkina Faso (IPC/BF) Ouagadougou Burkina Faso Unité de Formation et de Recherche en Sciences de la Sant&eacute (UFR-SDS) Universit&eacute Joseph KI-ZERBO Ouagadougou Burkina Faso

Introduction: The epidemiology of both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among drug users (dUs) is little known in West Africa. The study aimed to assess the prevalence of hepatitis B and C viruses among drug users in Burkina Faso. Methodology: This was a cross-sectional biological and behavioral survey conducted between June and August 2022, among drug users in Ouagadougou and Bobo dioulasso, the two main cities of Burkina Faso. A respondent-driven sampling (RdS) was used to recruit drug users. Hepatitis B surface antigen was determined using lateral flow rapid test kits and antibodies to hepatitis C virus in serum determined using an Enzyme-Linked Immunosorbent Assay. data were entered and analyzed using Stata 17 software. Weighted binary logistic regression was used to identify the associated factors of hepatitis B and C infections and a p-value Results: A total of 323 drug users were recruited with 97.5% males. The mean age was 32.7 years old. The inhaled or smoked mode was the most used by drug users. The adjusted hepatitis B and hepatitis C prevalence among study participants were 11.1% and 2.3% respectively. The marital status (p = 0.001), and the nationality (p = 0.011) were significantly associated with hepatitis B infection. The type of drug used was not significantly associated with hepatitis B infection or hepatitis C infection. Conclusion: The prevalence of HBsAg and anti-HCV antibodies among dUs are comparable to those reported in the general population in Burkina Faso. This result suggests that the main routes of contamination by HBV and HCV among dUs are similar to those in the population, and could be explained by the low use of the injectable route by dUs in Burkina Faso.

关键词： drug Users Hepatitis C Hepatitis B Prevalence Burkina Faso

deactivation of Streptococcus mutans Biofilms on a Tooth Surface Using He dielectric Barrier discharge at Atmospheric Pressure

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Plasma Science and Technology 2013年第6期15卷 535-541页

作者： Imola MOLNAR Judit PAPP Alpar simon Sorin dan ANGHEL Babes-Bolyai University Faculty of Biology and GeologyCluj-Napoca 400015Romania Babes-Bolyai University Faculty of PhysicsCluj-Napoca 400084Romania

This paper presents a study of the effect of the low temperature atmospheric helium dielectric barrier discharge（dBd） on the Streptococcus mutans biofilms formed on tooth surface. Pig jaws were also treated by plasma to detect if there is any harmful effect on the *** plasma was characterized by using optical emission *** data indicated that the discharge is very effective in deactivating Streptococcus mutans *** can destroy them with an average decimal reduction time（d-time） of 19 s and about 98%of thein were killed after a treatment time of 30 *** to the survival curve kinetic an overall 32 s treatment time would be necessary to perform a complete *** experimental results presented in this study indicated that the helium dielectric barrier discharge,in plan-parallel electrode configuration,could be a very effective tool for deactivation of oral bacteria and might be a promising technique in various dental clinical applications.

关键词： Streptococcus mutans dielectric barrier discharge plasma treatment biofilm deactivation sterilization

Thermochemical Treatment——Technologies for Recovery and Utilisation of Materials

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过程工程学报 2006年第2期6卷 231-236页

作者： Gerd Kley Rudolf Brenneis Burkart Adamczyk Franz-Georg simon division Waste Treatment and Remedial Eng. Federal Inst. Materials Research and Testing BAM Berlin 12200 Germany

The arc furnace technology is an ideally suited process for the treatment of hazardous and problematic waste. The operation conditions of the furnace can be adapted for optimal transformation of the waste material input into raw materials and usable products. The process can significantly reduce the impact of contaminated wastes and industrial residues, and enable material conversion and separation. Thus, the products of the process have various applications. The capability of the process is illustrated with three examples, the treatment of bottom ash and filter ash from waste incineration plants, of stainless steel slags and of chromium-containing residues from the refractory industry.

关键词：热化学处理原料分离耐火材料不锈钢

Evaluating organic acids as alternative leaching reagents for rare earth elements recovery from NdFeB magnets

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Journal of Rare Earths 2023年第4期41卷 621-631页

作者： Sahar Belfqueh Alain Seron simon Chapron Guilhem Arrachart Nourredine Menad BRGM Direction de l'Eaude l'Environnementdes Procédés et AnalysesOrleansFrance ICSM Univ.MontpellierCEACNRSENSCMMarcouleFrance

This study proposes an advanced leaching method using organic acids to recover rare earth elements(REEs)from NdFeB permanent magnets from end-of-life computers hard disk drives(Hdds).The end-oflife Hdds were first dismantled in order to recover NdFeB magnets,which were then thermally demagnetized at 350℃during 30 min before crushing in a ball mill under inert *** electron microscopy/energy dispersive X-ray spectroscopy(SEM/EdS)analyses performed on the NdFeB magnets show the heterogeneous structure containing the major matric phase Nd_(2)Fe_(14)B and the REEsrich phase containing Nd and Pr ***,X-ray diffraction(XRd)and Mossbauer spectroscopy(MS)analyses on the ground NdFeB magnet show that grinding NdFeB magnets under inert atmosphere helps to minimize its *** analysis shows that the composition of the ground sample is Nd:22.8 wt%,Pr:3.3 wt%,dy:1.2 wt%,Fe:62.6 wt%,Co:1.5 wt%,B:0.9 wt%,Ni:0.6 wt%.diagrams of speciation and equilibrium phases(E_(h) ***)were calculated to determine the predominance of the formed species in the REEs-organic acids *** influence of the organic acid type(acetic acid,formic acid,citric acid and tartaric acid),the acid concentration(10 vol%,up to saturation),and the solid/liquid(S/L)ratio(0.5%-10%)on NdFeB magnets leaching was investigated employing an optimal experimental design conceived by the statistical software *** acid(CH_(3)COOH)shows the highest leaching performance of REEs,allowing leaching yields over 90%for Nd,dy and Pr in the acid concentration range of 1.6-10 mol/L and the S/L ratio range of 0.5%-5%at a temperature of 60℃.The results presented in this investigation suggest that REEs can be recovered from magnets of end-of-life Hdds using an eco-friendly method assisted by organic acids.

关键词： NdFeB magnets Rare earth elements Leaching Organic acids Acetic acid

3d-QSAR analysis of a new type of acetylcholinesterase inhibitors

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Science China(Life Sciences) 2007年第6期50卷 726-730页

作者： LEE simon M. Y Institute of Chinese Medical Sciences University of Macao Av. Padre Tomas Pereira S. J. Taipa Macao China

Acetylcholinesterase (AChE) inhibitors are an important class of medicinal agents used for the treatment of Alzheimer’s disease. A screening model of AChE inhibitor was used to evaluate the inhibition of a series of phenyl pentenone derivatives. The assay result showed that some compounds displayed higher inhibitory effects. In order to study the relationship between the bioactivities; the structures, 26 compounds with phenyl pentenone scaffold were analyzed. A 3d-QSAR model was constructed using the method of comparative molecular field analysis (CoMFA). The results of cross-validated R[2]cv=0.629, non-cross-validated R[2]=0.972, SE=0.331,; F=72.41 indicate that the 3d-model possesses an ability to predict the activities of new inhibitors,; the CoMFA model would be useful for the future design of new AChE inhibitors.

关键词： acetylcholinesterase (AChE), comparative molecular field analysis (CoMFA), phenyl pentenone derivatives

Incidence and mortality of primary liver cancer in England and Wales: Changing patterns and ethnic variations

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World Journal of Gastroenterology 2014年第6期20卷 1544-1553页

作者： Nimzing G Ladep Shahid A Khan Mary ME Crossey Andrew V Thillainayagam simon d Taylor-Robinson Mireille B Toledano Gastroenterology and Hepatology Section Division of Diabetes Endocrinology and Metabolism Department of Medicine Imperial College London MRC-HPA Centre for Environment and Health Department of Epidemiology and Biostatistics School of Public Health Imperial College London

AIM: To explore recent trends, modes of diagnosis, ethnic distribution and the mortality to incidence ratio of primary liver cancer by subtypes in England and Wales.

关键词： Primary liver cancer Hepatocellular carcinoma Intrahepatic bile duct England and Wales Ethnicity

Tsunami Balls:A Granular Approach to Tsunami Runup and Inundation

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Communications in Computational Physics 2008年第1期3卷 222-249页

作者： Steven N.Ward simon day Institute of Geophysics and Planetary Physics University of CaliforniaSanta CruzCA 95064USA.

This article develops a new,granular approach to tsunami runup and *** small grains employed here are not fluid,but bits,or balls,of tsunami *** careful formulation of the ball accelerations,both wave-like and flood-like behaviors are accommodated so tsunami waves can be run seamlessly from deep water,through wave breaking,to the final surge onto shore and back *** deep water,tsunami balls track according long wave ray *** land,tsunami balls behave like a water *** shallow water,the balls embody both deep water and on land *** modeling several 2-d and 3-d cases,we find that wave breaking generally causes relative runup to increase with beach slope and wave period and decrease with input wave *** of their highly non-linear nature,runup and inundation are best considered to be random processes rather than deterministic *** and observations hint that for uniform input waves,normalized runup statistics everywhere follow a single skewed distribution with a spread between 1/2 and 2 times its mean.

关键词： Water wave tsunami run up.

Population growth, trophic level, and reproductive biology of two congeneric archer fishes (Toxotes chatareus, Hamilton 1822 and Toxotes jaculatrix, Pallas 1767) inhabiting Malaysian coastal waters

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第12期10卷 902-911页

作者： K. d. simon Y. BAKAR A. SAMAT C. C. ZAIdI A. AZIZ A. G. MAZLAN Marine Science Programme School of Environmental and Natural Resource Sciences Faculty of Science and Technology Universiti Kebangsaan Malaysia43600 UKM Bangi Selangor D.E. Malaysia Biology Programme School of Biological Sciences Universiti Kebangsaan Malaysia43600 UKM Bangi Selangor D.E. Malaysia Marine Ecosystem Research Centre Faculty of Science and Technology Universiti Kebangsaan Malaysia43600 UKM Bangi Selangor D.E. Malaysia department of Aquaculture Faculty of Agriculture Universiti Putra Malaysia43400 Serdang Selangor D.E. Malaysia

Population growth, trophic level, and some aspects of reproductive biology of two congeneric archer fish species, Toxotes chatareus and Toxotes jaculatrix, collected from Johor coastal waters, Malaysia, were studied. Growth pattern by length-weight relationship (W=aLb) for the sexes differed, and exhibited positive allometric growth (male, female and combined sexes of T. chatareus; female and combined sexes of T. jaculatrix) and isometric growth (male samples of T. jaculatrix only). Trophic levels of both species were analyzed based on 128 specimens. The results show that, in both species, crustaceans and insects were the most abundant prey items, and among crustaceans the red clawed crab Sesarma bidens and Formicidae family insects were the most represented taxa. The estimated mean trophic levels for T. chatareus and T. jaculatrix were 3.422±0.009 and 3.420±0.020, respectively, indicating that they are largely carnivores. Fecundity of T. chatareus ranged from 38 354 to 147 185 eggs for females with total length ranging from 14.5 to 22.5 cm and total body weight from 48.7 to 270.2 g, and T. jaculatrix 25 251 to 150 456 eggs for females with total length ranging from 12.2 to 23.0 cm and total body weight from 25.7 to 275.0 g. differences in values of gonadosomatic and hepatosomatic indexes calculated for both species in this study may have resulted from uneven sample size ranges.

关键词： Archer fish Toxotidae Mangrove Estuary Predator Growth Reproduction