检索结果-南通市图书馆

时效制度对2A97铝锂合金疲劳裂纹扩展速率的影响

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2016年第12期45卷 3319-3324页

作者：薛喜丽郑子樵胡芳张龙中南大学有色金属材料科学与工程教育部重点实验室湖南长沙410083

针对不同时效制度下2A97铝锂合金的疲劳裂纹扩展速率进行了研究;并通过光学显微镜、透射电镜和扫描电镜对合金的微观组织和疲劳断口进行了观察分析。结果表明:2A97合金薄板(T3+135℃/12 h)时效态的裂纹扩展速率最低,其次为T3,(T3+135℃/... 详细信息

针对不同时效制度下2A97铝锂合金的疲劳裂纹扩展速率进行了研究;并通过光学显微镜、透射电镜和扫描电镜对合金的微观组织和疲劳断口进行了观察分析。结果表明:2A97合金薄板(T3+135℃/12 h)时效态的裂纹扩展速率最低,其次为T3,(T3+135℃/60 h)时效态的扩展速率略低于(T3+135℃/120 h)时效态,T6态的裂纹扩展速率最高。时效制度在较低的ΔK水平下对合金的裂纹扩展速率影响较大,而在较高ΔK水平下影响较小。δ′相及细小的T1相可以促进共面滑移,增加滑移可逆性,降低裂尖应力集中程度及塑性累积水平,同时使裂纹发生偏折,促进裂纹闭合效应,提高裂纹扩展抗力;粗大、密集的T1相及半共格的θ′相抑制共面滑移,易于造成应力集中,降低裂纹扩展抗力;晶界处的无沉淀析出带(PFZ)及平衡相急剧降低晶界强度,极易造成沿晶开裂,使合金裂纹扩展速率迅速提高。

关键词： 2A97铝锂合金疲劳裂纹扩展速率时效制度析出相

在线全文

学校读者我要写书评

暂无评论

单级自养脱氮工艺氨氮去除途径研究

环境科学 2009年第1期30卷 102-107页

作者：杨国红方芳郭劲松秦宇魏英重庆大学三峡库区生态环境教育部重点实验室重庆400045

以SBBR单级自养脱氮系统的污泥为对象,采用不同的人工模拟废水为反应器进水,通过批式试验的方式研究了单级自养脱氮系统内的中间产物及氮素平衡情况,并探讨了氨氮的去除途径.结果表明,以仅含氨氮的人工模拟废水为进水,在未投加有机碳源... 详细信息

以SBBR单级自养脱氮系统的污泥为对象,采用不同的人工模拟废水为反应器进水,通过批式试验的方式研究了单级自养脱氮系统内的中间产物及氮素平衡情况,并探讨了氨氮的去除途径.结果表明,以仅含氨氮的人工模拟废水为进水,在未投加有机碳源的条件下,系统内62%的氨氮被转化为NO2-、NO3-、Nh2Oh、N2h4、NO、NO2、N2O和N2等一系列氮化合物,其中N2占90.07%.单级自养脱氮系统内的氨氮是由多种途径去除的.4.5%的氨氮是在吹脱等物化作用下去除的,不超过3.73%的氨氮是通过传统的硝化反硝化途径去除的,53.77%的氨氮是由自养脱氮途径去除的,自养脱氮反应起主要的脱氮作用,且自养脱氮反应可以通过2条代谢途径来实现.但在足够NO2存在并且缺氧的条件下,单级自养脱氮系统内的出水氨氮浓度与空白反应器相当,Nh4+并没有被亚硝化单胞菌以NO2为电子受体氧化为NO2-和N2等化合物而得以去除,可能是因为系统内不存在该类型的亚硝化功能菌.

关键词：单级自养脱氮氨氮途径厌氧氨氧化硝化反硝化

Effects of heat Treatment on Microstructure Evolution and Mechanical Properties of Mg-6Zn-1.4y-0.6Zr Alloy

在线全文

学校读者我要写书评

暂无评论

Effects of Heat Treatment on Microstructure Evolution and Me...

2016中国有色合金及特种铸造发展论坛

作者： WANG Jing fang Xiao-gang WU Shu-sen Lü Shu-lin State Key Lab of Materials Processing and Die & Mould Technology Huazhong University of Science and Technology

The effects of solution and aging treatments on the microstructure evolution and mechanical properties of the as-cast Mg-6 Zn-1.4 y-0.6 Zr alloy were *** results indicate that the solution treatment can obviously dissolve the net-like intermetallic compounds(mainly Ⅰ-phase) into theα-Mg ***,the I-phase decomposes gradually above 440℃,with the formation of fine W-phase and Mg7 Zn3 *** aging treatment results in the precipitation of numerous fine and dispersive particles in the α-Mg *** best mechanical properties of the heat treated alloy are obtained after solution treated at 460℃ for 8 h and aged at 200℃ for 16 h,with the yield strength(yS),ultimate tensile strength(UTS) and elongation are 208 MPa,257 MPa and 3.8%,*** with the as-cast alloy,the increment of yS and UTS are 117% and 58% respectively,while the decrement of elongation is 46%.

关键词： magnesium alloy heat treatment microstructure mechanical properties

Differentiation Induction effect of 4-Amino-2-Trifluoromethyl-Phenyl Retinate on human Breast Cancer MCF-7 Cell and its possible Mechanisms

在线全文

cnki会议

学校读者我要写书评

暂无评论

Differentiation Induction effect of 4-Amino-2-Trifluoromethy...

安徽省药理学会2012年学术年会

作者： Nan Wang Jin-fang Ge Chun-xiao Pan Fei-hu Chen School of Pharmacy Anhui Medical University

Aim To investigate the differentiation induction effect of 4-amino-2-trifluoromethyl-phenyl retinate(ATPR),which was a derivate of all trans-retinoic acid (ATRA) with anti-tumor activity,on human breast cancer MCF-7 cells and its possible *** MCF-7 cells were incubated without(control) or with ATPR(10,10, 10,10,10 and 10 mol/L) or ATRA(10 mol/L) for 72 *** proliferations were assessed by 3-(4,5-dimethylthiazol-2-thiazolyl)-2,5-diphenylterzolium bromide(MTT) assay,and morphologic changes were observed using inverted phase contrast microscope following Wright-Giemsa *** concentration of the differentiation maker mucin 1(MUC-1) was measured by enzyme linked immunosorbent assay(ELISA).The cell cycles were analyzed by flow *** mRNA expression of retinoic acid receptors(RARα,RARβ,and RARγ), estrogen receptors(ERαand ERβ),and retinoid receptor-induced gene-1(RRIG1) in different groups were detected by reverse transcription-polymerase chain reaction(RT-PCR).Results The survival rate of MCF-7 cells co-incubated with ATRA(10,10,10,10,10 and 10 mol/L) and ATPR(10 mol/L) were both significantly decreased as compared with the control *** inhibitory effect of ATPR enhanced as the time and the dose increasing,with the half inhibition concentration(IC) of ATPR being 61.78μmol·L,44.91μmol·L,7.79μmol·L and 11.38μmol·L for 24,48,72 and 96h,***-7 cells treated with ATPR showed higher degree of mature and differentiation than that in the control *** concentration of MUC-1 was significantly different between ATPR(10 mol/L) group(43.83±1.02 U/mL) and control group(56.76±5.18 U/mL).Compared with those of the control group,the percentage of G/G-phase cells in ATPR(10 and 10 mol/L) group were notably increased(Phile S-phase cells were remarkably decreased(Phe mRNA expression of RARβ,RRIG1 and ERβwere remarkably increased(Phe mRNA expression of RARγwas notably decreased(Phere was no significa

关键词： 4-amino-2-trifluoromethyl-phenyl retinate(ATPR) differentiation induction breast cancer cells RARs ERs retinoid receptor-induced gene-1

A Case of New Variant COVID-19 First Emerging in South Africa Detected in a Security Guard at the Isolation Point—Shenzhen,China,January 23,2021

在线全文

cnki会议

学校读者我要写书评

暂无评论

China CDC weekly 2021年第10期3卷 218-220页

作者： Jun Meng Shujiang Mei Long Chen Chunli Wu Shisong fang Bo Peng Dongfeng Kong Xiaomin Zhang Linghong Xiong yalan huang Qiongcheng Chen Renli Zhang yaqing he Department of Pathogenic Biology Shenzhen Center for Disease Control and PreventionShenzhenGuangdongChina Department of Communicable Diseases Control and Prevention Shenzhen Center for Disease Control and PreventionShenzhenGuangdongChina.

On January 22,2021,a 34-year-old male,who served as a security guard at the isolation point in Shenzhen,tested positive for coronavirus disease 2019(COVID-19)during the every-three-day routine *** the nasopharyngeal swab was further confirmed as positive for COVID-19 by Shenzhen CDC,the patient was transferred to the Third People’s hospital of Shenzhen and was diagnosed as a COVID-19 asymptomatic *** January 25,2021,Shenzhen CDC identified the 20h/501.y.V2(B.1.351)variant,which was a variant of COVID-19 virus first emerging in the South Africa.

关键词： routine nasopharyngeal Guard

Two new ursane-type triterpenoid glycosides from Ilex cornuta

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Two new ursane-type triterpenoid glycosides from Ilex cornut...

中国化学会第十二届全国天然有机化学学术会议

作者： hai-Xia ZhAN Gui-Feng Liu Juan LI hui-fang PI School of Pharmacy Tongji Medical CollegeHuazhong University of Science and TechnologyHubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation Pharmacy Department of Tongji hospital Tongji Medical CollegeHuazhong University of Science and Technology

Ilex cornuta is a kind of plant used for traditional Chinese medicines(TCM) for hundreds of *** order to provide more information about the chemical basis of its pharmacological effects,phytochemical investigation on the roots of *** was Ionducted in this *** new triterpenoid saponins(1,2),together with 12 known compounds(3-14).were isolated from the roots of *** structures were determined based on NMR,MS technologies,chemical reactions as well as *** 4,6,8,11,12 and 13 were isolated from this genus for the first time .The structures of compounds 1 and 2 were determined as 3β-O-α-Dxylopyranosyl-(1→3)-α-L-2-O-acetylarabinopyranosyl-(1→2)-β-D-glucopyranosyl-23-hydroxyl-20α(h)-urs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester(1) and 3 P-O-α-D-xylopyranosly-(1→3)-α-L-2-O-acetylarabinopyranosyl-(1→2)-β-D-glucopyranosyl-19α,23-dihydroxyl-20α(h)-urs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester(2).

关键词： Ilex cornuta Aquifoliaceae Triterpenoids Structural elucidation

Dry reforming of methane on active and coke resistant Ni/y_2Zr_2O_7 catalysts treated by dielectric barrier discharge plasma

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2016年第5期25卷 825-831页

作者： Xiuzhong fang Jie Lian Kaiwen Nie Xianhua Zhang yanfeng Dai Xianglan Xu Xiang Wang Wenming Liu Changqing Li Wufeng Zhou College of Chemistry Nanchang University Jiangxi Golden Century Advanced Materials Co. Ltd Nanchang

In this study, Ni/yZrOcatalysts prepared with impregnation method and treated by dielectric barrier discharge plasma(DBD) in different atmospheres have been investigated for methane dry reforming. It is revealed by h-TPR that plasma treatment can enhance the interaction between Ni O/Ni particles and the yZrOpyrochlore support. Therefore, catalysts with smaller Ni O and Ni grains sizes, higher metallic Ni active surface areas can be achieved, as evidenced by XRD, TEM and hadsorption-desorption measurements. As a consequence, the plasma-treated catalysts show significantly improved activity, stability and coke resistance, as testified by the TEM and TGA-DSC results. Plasma treatment in h/Ar gas mixture is found to be the best condition to prepare Ni/yZrO, which can be used to obtain a catalyst with the highest activity, stability and most potent coke resistance. It is believed that the smaller Ni grain size and higher metallic Ni active surface area induced by plasma treatment are the inherent reasons accounting for the promoted reaction performance of the Ni/yZrOpyrochlore catalysts.

关键词： Plasma treatment y2Zr2O7 pyrochlore support Supported Ni catalysts Methane dry reforming Coke resistance

Design,synthesis and in vitro evaluation of novel quinazolinone as DPP-4 inhibitors

在线全文

学校读者我要写书评

暂无评论

Design,synthesis and in vitro evaluation of novel quinazolin...

中国化学会第十二届全国天然有机化学学术会议

作者： Li-fang Wang Li-Cheng yi Juan Li Sheng-Ming Peng Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education College of ChemistryXiangtan University

A series of simple structure of quinazolin-4(3 h)-one compounds was designed and synthesized,the compounds that quinazolin-4(3 h)-one as mother nucleus,combining with the characteristics of DPP-4 crystal *** all compounds have been characterized through 1 h NMR and *** evaluate its biological activity in vitro enzyme inhibition ***,have a compound showed an IC at 96.15 ±0.65 nM,and close to the positive control *** through AutoDock4.2.6 software will target molecules with the DPP-4 enzyme molecular docking studies by Lamarck genetic algorithm.

关键词： Dipeptidyl peptidase-4 inhibitor quinazolin-4(3h)-one Synthesis

Metal-organic framework film for fluorescence turn-on h2S gas sensing and anti-counterfeiting patterns

在线全文

cnki会议

学校读者我要写书评

暂无评论

Science China Materials 2019年第10期62卷 1445-1453页

作者： Jun Zhang fang Liu Jiulin Gan yuanjing Cui Bin Li yu yang Guodong Qian State Key Laboratory of Silicon Materials Cyrus Tang Center for Sensor Materials and ApplicationsSchool of Material Science and EngineeringZhejiang UniversityHangzhou 310027China College of Electrical Engineering Zhejiang UniversityHangzhou 310027China State Key Laboratory of Luminescent Materials and Devices and Institute of Optical Communication Materials South China University of TechnologyGuangzhou 510640China

hydrogen sulphide(h2 S)is a common air pollutant,which is produced in various industry ***,it is of crucial importance to detect h2 S in real *** fluorescent sensors were reported aiming at detecting h2 S in solution;however,the fluorescence sensing of gaseous h2 S has not yet been *** this work,we utilized the post-functionalized fluorescent film,MIL-100(In)@Eu3+/Cu2+film,realizing fluorescence turn-on sensing of gaseous h2 S at room temperature for the first time with the limit of detection as low as 0.535 ppm,which is comparable to some reported fluorescent probes for S2-ions and semiconductor based gaseous h2 S *** sensor was designed due to the strong affinity of h2 S with Cu2+.With the formation of CuS,the"antenna effect"between the ligand and Eu3+recovered,resulting in the fluorescence turn-on of Eu3+***,we proposed a new method to realize multi-colour anti-counterfeiting patterns with lanthanide ions ink,taking advantage of the extraordinary smooth surface and uncoordinated carboxylate groups within the MIL-100(In)film.

关键词： h2S gas fluorescence sensing film anti-counterfeiting