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Bioactive Steroid from the Root Bark of Psorospermum corymbiferum

中国天然药物 2011年第4期9卷 264-266页

作者： Zubair MF Oladosu IA Olawore NO Usman LA Fakunle CO hamid aa Ali MS Department of Chemistry University of llorinNigeria Department of Chemistry University of IbadanNigeria Department of Chemistry Ladoke Akintola University of TechnologyOgbomoso Department of Chemistry Bowen UniversityIwoNigeria International Centre for Chemical and Biological Studies(ICCBS) Pakistan

AIM:To isolate,characterize and investigate the antifungal activity of the root bark of Psorospermum corymbiferum(Clusiaceae).METHODS:The finely ground root bark of Psorospermum corymbiferum was cold-extracted by percolation with 98% ethanol(5.0 L) for two *** ethanol extract was macerated with n-hexane,chloroform,ethylacetate and methanol successively to give the respective solvent *** of the extract was done using column chromatography on silica gel with cyclohexene:ethylacetate(1:1) as eluents,and the subfractions were purified by TLC using cyclohexane:ethylacetate(7:3).The structures were elucidated based on spectral analysis(IR,1H NMR and 13C NMR) in comparison with the data with those reported in the *** minimum inhibitory concentration(MIC) was determined on Candida alblican and Candida ***:Three known compounds,acetylvismione F,prenylated bianthrone and 1,8-dihydroxyanthraquinone and a steroid were isolated from the *** determined on Candida alblican and *** were 20 and 15 μ***-1,*** steroidal compound(diosgenin) was characterized for the first time from Psorospermum corymbiferum(Clusiaceae).CONCLUSION:The results suggested that the isolation has anticandidal properties,supporting the use of this plant in folk *** current drug of choice for disseminated Candidiasis is amphotericin B with MIC of 0.39 μ***-1,which could be a promising lead for a new antifungal drug especially if subjected to SAR in antifungal drug design.

关键词：生物活性化合物胆汁酸化学分析

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Efficacy of two chemical coagulants and three different filtration media on removal of Aspergillus flavus from surface water

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Journal of Environmental Sciences 2014年第2期26卷 274-280页

作者： hamid Mohammad Al-Gabr Tianling Zheng Xin Yu Key Laboratory of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences State Key Laboratory of Marine Environmental Science and Key Laboratory of MOE for Coast and Wetland Ecosystems School of Life SciencesXiamen University

Aquatic fungi are common in various aqueous environments and play potentially crucial roles in nutrient and carbon cycling as well as interacting with other organisms. Species of Aspergillus are the most common fungi that occur in water. The present study was undertaken to elucidate the efficacy of two coagulants, aluminum sulfate and ferric chloride, used at different concentrations to treat drinking water, in removing Aspergillusflavus, as well as testing three different filtration media： sand, activated carbon, and ceramic granules, for their removal of fungi from water. The results revealed that both coagulants were effective in removing fungi and decreasing the turbidity of drinking water, and turbidity decreased with increasing coagulant concentration. Also, at the highest concentration of the coagulants, A. flavus was decreased by 99.6% in the treated water. Among ceramic granules, activated carbon, and sand used as media for water filtration, the sand and activated carbon filters were more effective in removing *** than ceramic granules while simultaneously decreasing the turbidity levels in the test water samples. Post-treatment total organic carbon （TOC） and total nitrogen （TN） concentrations in the experimental water did not decrease; on the contrary, TN concentrations increased with the increasing dosage of coagulants. The filtration process had no effect in reducing TOC and TN in tested water.

关键词： Aspergillus flavus coagulation filtration drinking water

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Role of heat balance on the microstructure evolution of cold spray coated AZ31B with aa7075

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Journal of Magnesium and Alloys 2021年第4期9卷 1467-1478页

作者： Bahareh Marzbanrad Mohammad Hadi Razmpoosh Ehsan Toyserkani hamid Jahed Mechanical and Mechatronics Engineering Department University of WaterlooCanada

A promising solid-state coating mechanism based on the cold spray technique provides highly advantageous conditions on thermal-sensitive magnesium *** study the effect of heat balance in cold spray coating on microstructure,experiments were designed to successfully coat aa7075 on AZ31B with two different heat balance conditions to yield a coated sample with tensile residual stress and a sample with compressive residual stress in both coating and *** effects of coating temperature on the microstructure of magnesium alloy and the interfaces of coated samples were then analyzed by SEM,EBSD,TEM in high-and low-heat input coating *** interface of the aa7075 coating and magnesium alloy substrate under both conditions consists of a narrow-band layer with very fine grains,followed by columnar grains of magnesium that have grown perpendicular to the *** higher temperatures,this layer became *** intermetallic phase was detected at the interface under either *** is shown that the microstructure of the substrate was affected by coating temperature,leading to stress relief,dynamic recrystallization and even dynamic grain growth of magnesium under high *** the heat input and increasing the heat transfer decreased microstructural changes in the substrate.

关键词： Cold spraying Heat balance Microstructural analysis Coating interface Magnesium Alloy AZ31B Residual Stress

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Prediction of the Microstructural Variations of Cold-Worked Pure Aluminum during Annealing Process

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Modeling and Numerical Simulation of Material Science 2015年第1期5卷 1-14页

作者： hamid Reza Rezaei Ashtiani Peyman Karami School of Mechanical Engineering Arak University of Technology Arak Iran

The mechanical properties such as hardness and ultimate tensile strength of metals depend on the grain size, which have to be properly controlled and optimized to ensure the better economy and desirable mechanical characteristics of the metals. In order to study the microstructure evolution of aa1070, many experimental tests were conducted at different cold working and annealing conditions. Utilizing the experimental results, the static recrystallization and grain growth behavior of aa1070 have been investigated and the developed equations that can be used to the FEM of the annealing process have been obtained. The agreement between numerical modeling and experimental results is reasonably good for this material. The results showed that the recrystallization and grain growth behavior of aa1070 was evidently affected by both the annealing temperature and plastic strain.

关键词： Grain Size Annealing Static Recrystallization Grain Growth FEM

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Microstructure and Quasi-Static Mechanical Behavior of Cryoforged aa2519 Alloy

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Materials Sciences and Applications 2019年第2期10卷 137-149页

作者： Amin Azimi Gbadebo Moses Owolabi hamid Fallahdoost Nikhil Kumar Horace Whitworth Department of Mechanical Engineering Howard University Washington DC USA Department of Mechanical Engineering Materials Science and Engineering Program Binghamton University (SUNY) Binghamton NY USA

In this study, aa2519 alloy was initially processed by multi axial forging (MAF) at room and cryogenic temperatures. Subsequently, the microstructure and the mechanical behavior of the processed samples under quasi-static loading were investigated to determine the influence of cryogenic forging on alloys’ subgrains dimensions, grain boundaries interactions, strength, ductility and toughness. In addition, the failure mechanisms at the tensile rupture surfaces were characterized using scanning electron micro-scope (SEM). The results show significant improvements in the strength, ductility and toughness of the alloy as a result of the cryogenic MAF process. The formation of nanoscale crystallite microstructure, heavily deformed grains with high density of grain boundaries and second phase breakage to finer particles were characterized as the main reasons for the increase in the mechanical properties of the cryogenic forged samples. The cryogenic processing of the alloy resulted in the formation of an ultrafine grained material with tensile strength and toughness that are ~41% and ~80% higher respectively after 2 cycles MAF when compared with the materials processed at ambient temperature. The fractography analysis on the tested materials shows a substantial ductility improvement in the cryoforged (CF) samples when compared to the room temperature forged (RTF) samples which is in alignment with their stress-strain profiles. However, extended forging at higher cycles than 2 cycles led only to increase in strength at the expense of ductility for both the CF and RTF samples.

关键词： aa2519 Aluminum Alloy Cryogenic Forging Quasi-Static Mechanical Behavior Microstructure Investigation Fractography Analysis

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Association between the cytotoxic T-lymphocyte antigen-4 polymorphisms and breast cancer risk and prognosis

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Journal of Cancer Metastasis and Treatment 2015年第1期1卷 16-20页

作者： Meraj Farbod Seyed Mostafa Shiryazdi hamid Harazi Tahereh Nazari Mohammad Hasan Sheikhha Department of General Surgery Shahid Rahnemon HospitalShahid Sadoughi University of Medical SciencesYazd ***Iran Department of General Surgery Shahid Sadoughi HospitalShahid Sadoughi University of Medical SciencesYazd ***Iran Department of General Surgery Shohada-Kargar HospitalSocial Security OrganizationYazd ***Iran Department of Human Genetics International CampusShahid Sadoughi University of Medical SciencesYazd ***Iran Department of Medical Genetics Research and Clinical Center for InfertilityShahid Sadoughi University of Medical SciencesYazd ***Iran

Aim:The aim was to evaluate the potential infl uences of cytotoxic T-lymphocyte antigen-4(CTLA-4)gene polymorphisms on breast cancer risk,the distribution of CTLA-4 single nucleotide polymorphisms(1661AG)in breast cancer patients and control subjects was ***:In this case-control study,100 patients with breast cancer as case group and 100 healthy participants as a control group were *** were determined by the polymerase chain reaction-restriction fragment length polymorphism *** characteristics of the study population,as well as tumor size,tumor grade and stage were collected in a questionnaire designed for this *** collected data were statistically analyzed by SPSS-16.0(SPSS Inc.,Chicago,USA)predictive analytic software using the Chi-square ***:The mean age of women was 43.42±13.1 *** aa genotype was frequent in case group(43%)whereas the AG genotype was found more in the control group(69%).There was no signifi cant relationship between the studied polymorphisms and the grade,stage and size of the tumor,nor between the studied polymorphisms and estrogen receptor,progesterone receptor and lymph node involvement(P>0.05).Signifi cant association between the studied polymorphisms and breast cancer metastases was found(P=0.02).Conclusion:According to the results of the study,the aa genotype is associated with breast cancer,but none of the studied gene polymorphisms is associated with prognostic factors such as tumor stage,grade or size.

关键词： Breast cancer cytotoxic T-lymphocyte antigen-4 polymorphism prognosis

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归一化标准偏差法估计重磁源边界

归一化标准偏差法估计重磁源边界

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中国地球物理学会第二十四届年会

作者：陈召曦孟小红郭良辉 Aghajani hamid 地下信息探测技术与仪器教育部重点实验室＜中国地质大学北京＞

＜正＞目前在重磁勘探中,已有许多方法可用来估计重磁源的边界位置。Bhattacharya提出用二阶垂直导数法来定位场源边界;Nabighian提出解析信号法,在解析信号振幅剖面图中解析信号振幅的最大值处为场源边界;Hood和Teskey等人提出利用水...

＜正＞目前在重磁勘探中,已有许多方法可用来估计重磁源的边界位置。Bhattacharya提出用二阶垂直导数法来定位场源边界;Nabighian提出解析信号法,在解析信号振幅剖面图中解析信号振幅的最大值处为场源边界;Hood和Teskey等人提出利用水平梯度法和垂直梯度法来探测物体的垂直边界,Telford等人提出用最大梯度法可以定位重磁源的边界。余钦范和楼海进一步探讨

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