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Microstructures,corrosion behavior and mechanical properties of as-cast Mg-6Zn-2X(Fe/Cu/Ni)alloys for plugging tool applications
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作者 Baosheng Liu Jiali Wei +4 位作者 shaohua zhang Yuezhong zhang Pengpeng Wu Daqing Fang Guorui Ma 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期697-711,共15页
Mg-6Zn-2X(Fe/Cu/Ni)alloys were prepared through semi-continuous casting,with the aim of identifying a degradable magnesium(Mg)alloy suitable for use in fracturing balls.A comparative analysis was conducted to assess t... Mg-6Zn-2X(Fe/Cu/Ni)alloys were prepared through semi-continuous casting,with the aim of identifying a degradable magnesium(Mg)alloy suitable for use in fracturing balls.A comparative analysis was conducted to assess the impacts of adding Cu and Ni,which result in finer grains and the formation of galvanic corrosion sites.Scanner electronic microscopy examination revealed that precipitated phases concentrated at grain boundaries,forming a semi-continuous network structure that facilitated corrosion penetration in Mg-6Zn-2Cu and Mg-6Zn-2Ni alloys.Pitting corrosion was observed in Mg-6Zn-2Fe,while galvanic corrosion was identified as the primary mechanism in Mg-6Zn-2Cu and Mg-6Zn-2Ni alloys.Among the tests,the Mg-6Zn-2Ni alloy exhibited the highest corrosion rate(approximately 932.9 mm/a)due to its significant potential difference.Mechanical testing showed that Mg-6Zn-2Ni alloy possessed suitable ultimate compressive strength,making it a potential candidate material for degradable fracturing balls,effectively addressing the challenges of balancing strength and degradation rate in fracturing applications. 展开更多
关键词 magnesium alloys microstructure micro-galvanic corrosion mechanical properties
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Ultrafast Synthesis of Metal-Layered Hydroxides in a Dozen Seconds for High-Performance Aqueous Zn(Micro-)Battery 被引量:2
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作者 Xiangyang Li Fangshuai Chen +9 位作者 Bo Zhao shaohua zhang Xiaoyu Zheng Ying Wang Xuting Jin Chunlong Dai Jiaqi Wang Jing Xie Zhipan zhang Yang Zhao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第3期16-31,共16页
Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly re... Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly rely on traditional bottom-up method,which involves tedious steps,time-consuming treatments,or additional alkaline media,and is unfavorable for high-efficiency production.Herein,we present a facile,ultrafast and general avenue to synthesize transition metal hydroxides on carbon substrate within 13 s by Joule-heating method.With high reaction kinetics caused by the instantaneous high temperature,seven kinds of transition metal-layered hydroxides(TM-LDHs)are formed on carbon cloth.Therein,the fastest synthesis rate reaches~0.46 cm^(2)s^(-1).Density functional theory calculations further demonstrate the nucleation energy barriers and potential mechanism for the formation of metal-based hydroxides on carbon substrates.This efficient approach avoids the use of extra agents,multiple steps,and long production time and endows the LDHs@carbon cloth with outstanding flexibility and machinability,showing practical advantages in both common and micro-zinc ion-based energy storage devices.To prove its utility,as a cathode in rechargeable aqueous alkaline Zn(micro-)battery,the NiCo LDH@carbon cloth exhibits a high energy density,superior to most transition metal LDH materials reported so far. 展开更多
关键词 Ultrafast synthesis Thermal shock Metal-layered hydroxides Zn(micro-)battery
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Fast charge transport motivated by tunable Mo2C/Mo2N high-quality heterointerface for superior pseudocapacitive storage
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作者 Yanjun Gao shaohua zhang +5 位作者 Lingrui Xu Xiangyang Li Lijie Li Lixia Bao Jiong Peng Xin Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期465-477,I0012,共14页
The development of potential transition-metal carbide/nitride heterojunctions is hindered by overall understanding and precise modulation for heterointerface effects.Herein,we demonstrate that Mo_(2)C/Mo_(2)N heteroju... The development of potential transition-metal carbide/nitride heterojunctions is hindered by overall understanding and precise modulation for heterointerface effects.Herein,we demonstrate that Mo_(2)C/Mo_(2)N heterojunction with the precisely regulated high-quality interface can achieve marvelous rate performance and energy output via enlarging the interface-effect range and maximizing "accelerated charge" amount The heterointerface mechanism improving properties is synergistically revealed from kinetics and thermodynamics perspectives.Kinetics analysis confirms that the self-built electric field affords a robust force to drive rapid interface electrons/ions migration.The small adsorption energy,high density of states and quite low diffusion barrier thermodynamically enhance the electrochemical reaction dynamics on heterointerface.Consequently,the almost optimal performance of ultrahigh capacitance retention(85.6% even at 10 A g^(-1)) and pronounced energy output(96.4 Wh kg^(-1))in hybridsupercapacitors than other Mo_(2)C/Mo_(2)N-based materials is presented.This work gives new insight into the energy storage mechanism of heterojunction and guides the design of advanced electrodes. 展开更多
关键词 Energy storage Hybrid supercapacitors PSEUDOCAPACITANCE HETEROJUNCTION High-quality interface
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锌铜复合氧化物负载的金纳米粒子在无碱条件下催化多种醇高效选择性氧化(英文)
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作者 汪伟 谢妍 +5 位作者 张少华 刘星 张历云 张炳森 春田正毅 黄家辉 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第12期1924-1933,共10页
醇选择性氧化为醛和酮是化学工业上的重要反应.醛和酮是广泛应用于合成医药、农药和香料等精细化学品的重要化学中间体.过去常用化学计量的氧化剂来实现醇的选择性氧化,但会带来严重的环境污染.目前,很多研究工作致力于发展环境友好的... 醇选择性氧化为醛和酮是化学工业上的重要反应.醛和酮是广泛应用于合成医药、农药和香料等精细化学品的重要化学中间体.过去常用化学计量的氧化剂来实现醇的选择性氧化,但会带来严重的环境污染.目前,很多研究工作致力于发展环境友好的催化体系,利用分子氧来实现醇的高效选择性氧化.在过去的30年里,金催化剂在多种气相和液相反应中的催化性能和反应机理已被深入研究.近年来,金催化剂在醇选择性氧化反应中表现出高的催化活性和特殊的选择性.设计和制备合适的载体对金催化剂取得优异的醇氧化催化活性有至关重要的作用.先前的研究工作报道氧化锌是一种碱性材料,其表面没有酸性位.Au/ZnO催化剂在苯甲醇氧化反应中表现出高的苯甲醛选择性和低的苯甲醇转化率.在本研究工作中,我们向ZnO载体中掺杂Cu元素,制备出一系列ZnO-CuO复合氧化物,并进一步负载金用于催化苯甲醇氧化反应.研究结果表明,在无碱的反应条件下,Au/ZnO-CuO催化剂比Au/ZnO和Au/CuO催化剂具有更高的苯甲醇氧化催化活性,其中Au/Zn0.7Cu0.3O催化剂表现出最优的催化活性.我们还研究了反应温度和氧气压力对Au/Zn0.7Cu0.3O催化苯甲醇选择性氧化活性的影响,探索了Au/Zn0.7Cu0.3O催化剂对多种醇氧化反应的普遍适用性,考察了Au/Zn0.7Cu0.3O催化剂对醇氧化反应的催化循环性能.我们发现Au/Zn0.7Cu0.3O催化剂在无碱温和的反应条件下可以将1-苯基乙醇、对甲基苯甲醇、对异丙基苯甲醇、二苯甲醇、环丙基苯甲醇和肉桂醇高效选择性氧化为对应的羰基化合物,但对正辛醇氧化反应表现出相对较低的催化活性.此外,Au/Zn0.7Cu0.3O催化剂在苯甲醇氧化反应的催化循环中容易失活,而在1-苯基乙醇氧化反应的催化循环中则表现出较好的稳定性.利用X射线衍射、氮气吸脱附、氢气程序升温还原、透射电子显微镜、二氧化碳程序升温脱附和氧气程序升温脱附等方法对金催化剂的物化性质进行了表征,并提出了金催化苯甲醇选择性氧化可能的反应机理.我们认为Au/Zn0.7Cu0.3O催化剂优异的催化活性与其小的金粒径、好的低温还原性能、高的表面氧物种含量、表面酸碱性及金粒子与载体的协同效应等密切相关. 展开更多
关键词 金催化 锌铜复合氧化物 有氧氧化 无碱反应
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中国城市规模分布特征研究--基于2010-2019年普查数据的分析 被引量:4
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作者 陈洁仪 张少华 潘丽群 《产业经济评论》 CSSCI 2022年第1期185-200,共16页
城市规模分布能够度量一个国家城市之间的发育特征和反映该国城市化进程中存在的问题。基于五普、六普和2015—2019年312个城市和自治州常住人口数据,本文运用Zipf回归、首位度指数、空间基尼系数和马尔科夫转移矩阵的方法,测度了中国... 城市规模分布能够度量一个国家城市之间的发育特征和反映该国城市化进程中存在的问题。基于五普、六普和2015—2019年312个城市和自治州常住人口数据,本文运用Zipf回归、首位度指数、空间基尼系数和马尔科夫转移矩阵的方法,测度了中国城市规模的分布特征。研究发现:(1)从城市规模分布的总体特征来看,当前中国城市规模分布较为分散,即低位序的中小城市发育更加突出,大城市发育不够充分;但城市规模分布的变化趋势整体是朝着集中化方向发展,且集中化趋势在放缓。(2)从城市规模分布的区域特征来看,西部地区城市规模发育最为成熟,但集中度呈现下降趋势;东部、中部地区城市规模分布都远低于理想水平,东部地区集中度呈现上升趋势,而中部地区基本保持不变。(3)从城市规模的省域特征来看,绝大部分的省域内部城市结构不理想,有的省域城市体系具有“双核”或“三核”等特征,存在巨大的改善空间。(4)从城市规模分布的结构演化特征来看,中国城市规模是相对稳定的,同时存在着一条由中小城市逐步发展为大城市的成长路径。本文研究对认识当前中国城市化进程和未来中国城市体系格局如何调整有重要的参考价值。 展开更多
关键词 城市规模 Zipf回归 首位度指数 空间基尼系数 马尔科夫转移矩阵
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Geochemistry,geochronology and Hf isotope of granitoids in the northern Alxa region:Implications for the Late Paleozoic tectonic evolution of the Central Asian Orogenic Belt 被引量:2
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作者 Xiaochen Zhao Chiyang Liu +2 位作者 Jianqiang Wang shaohua zhang Yuzhao Guan 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第5期1711-1725,共15页
The tectonic setting of the northern Alxa region during the Late Paleozoic is highly controversial.The key to resolve this controversy is to recognize the Late Paleozoic magmatic processes in the northern Alxa.In this... The tectonic setting of the northern Alxa region during the Late Paleozoic is highly controversial.The key to resolve this controversy is to recognize the Late Paleozoic magmatic processes in the northern Alxa.In this paper,we present new zircon U-Pb ages,Hf-isotopic compositions and whole-rock geochemical data of four granitoids along the Zhusileng-Hangwula Tectonic Belt in the northern Alxa region that could provide critical information about the tectonic evolution of this region.The zircon U-Pb data could be grouped as two phases:Late Devonian granite and diorite(ca.373-360 Ma),and Late Carboniferous granodiorite(ca.318 Ma).The Late Devonian granites and diorites are metaluminous to slightly peraluminous,with A/CNK and A/NK ratios of 0.90-1.11 and0.95-2.19,respectively.The Late Devonian diorites are characterized by high MgO,Cr and Ni contents and MgO#values,together with variableεHf(t)values from-1.0 to+1.3 and old TDM2 ages varied from 1283 Ma to 1426 Ma,indicating the primary magma was potentially derived from magma mixing of depleted mantle with Mesoproterozoic continental crust.Even though the Late Devonian granites yielded most positive and minor negative eHf(t)values between-1.1 to+5.7(three grains are negative)with two-stage model ages(TDM2)of 1003-1438 Ma,they display low MgO,Cr and Ni contents and MgO#values,suggesting that they were mainly derived from juvenile crustal materials,mixed with a small amount of ancient crust.The Late Carboniferous granitoids are metaluminous and medium-K calc-alkaline series,with A/CNK and A/NK ratios ranging from 0.88 to 0.95 and1.75 to 1.90,respectively.These rocks were potentially derived from juvenile crustal materials mixed with depleted mantle,as evidenced by their highεHf(t)values(+11.6 to+14.1)and young TDM2 ages(427 Ma to 586 Ma),as well as high Mg#values,and MgO,Ni and Cr contents.Our data,along with available sedimentary evidence and previous researches,indicate that the Late Devonian and Late Carboniferous rocks are arc-related granitoids under the subduction setting.The identification of arc-related granitoids in the northern Alxa region not only reveals the Late Paleozoic magmatic process in response to the subduction of Paleo Asian Ocean,but also provide significant constrains to the tectonic evolution of the Central Asian Orogenic Belt. 展开更多
关键词 GEOCHEMISTRY U–Pb geochronology Hf isotopic composition GRANITOIDS Northern Alxa region Central Asian Orogenic Belt
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On the source of the quasi-Carrington Rotation periodic magnetic variations on the Martian surface: InSight observations and modeling 被引量:2
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作者 Hao Luo AiMin Du +6 位作者 shaohua zhang YaSong Ge Ying zhang ShuQuan Sun Lin Zhao Lin Tian SongYan Li 《Earth and Planetary Physics》 EI CSCD 2022年第3期275-283,共9页
In a recent paper(Luo H et al.,2022),we found that the peak amplitudes of diurnal magnetic variations,measured during martian days(sols)at the InSight landing site,exhibited quasi Carrington-Rotation(qCR)periods at hi... In a recent paper(Luo H et al.,2022),we found that the peak amplitudes of diurnal magnetic variations,measured during martian days(sols)at the InSight landing site,exhibited quasi Carrington-Rotation(qCR)periods at higher eigenmodes of the natural orthogonal components(NOC);these results were based on~664 sols of magnetic field measurements.However,the source of these periodic variations is still unknown.In this paper we introduce the neutral-wind driven ionospheric dynamo current model(e.g.,Lillis et al.,2019)to investigate the source.Four candidates-the draped IMF,electron density/plasma density,the neutral densities,and the electron temperature in the ionosphere with artificial qCR periodicity,are applied in the modeling to find the main factor likely to be causing the observed surface magnetic field variations that exhibit the same qCR periods.Results show that the electron density/plasma density,which controls the total conductivity in the dynamo region,appears to account for the greatest part of the surface qCR variations;its contribution reaches about 67.6%.The draped IMF,the neutral densities,and the electron temperature account,respectively,for only about 12.9%,10.3%,and 9.2%of the variations.Our study implies that the qCR magnetic variations on the Martian surface are due primarily to variations of the dynamo currents caused by the electron density variations.We suggest also that the timevarying fields with the qCR period could be used to probe the Martian interior's electrical conductivity structure to a depth of at least 700 km. 展开更多
关键词 INSIGHT sol magnetic variations Carrington Rotation(CR)periodicity
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Hydrothermal Treatment of Sol-Gel TiO_2 Film 被引量:1
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作者 shaohua zhang Bing Xie +1 位作者 Fengyi Li Tude Zou 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期570-571,共2页
The preparation of TiO_2 film has been an important research area.In our work,we obtained the TiO_2 film by hydrothermal treating the amorphous film prepared by sol-gel method or the hydrolysis of titanium alkoxide.Th... The preparation of TiO_2 film has been an important research area.In our work,we obtained the TiO_2 film by hydrothermal treating the amorphous film prepared by sol-gel method or the hydrolysis of titanium alkoxide.The influence of temperature and duration time on the film properties was investigated.The photo degradation of methyl orange in aqueous solution of the film was studied.The films were characterized by XRD and Uv-Vis spectroscope. 展开更多
关键词 TITANIA FILM HYDROTHERMAL SOL-GEL
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Effectiveness of second-line anti-HER2 treatment in HER2-positive metastatic breast cancer patients previously treated with trastuzumab:A real-world study 被引量:1
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作者 Wei Zhao Li Bian +4 位作者 Tao Wang shaohua zhang Jianbin Li Fengrui Xu Zefei Jiang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2020年第3期361-369,共9页
Objective:Several studies have demonstrated different benefits for patients whose disease progressed despite previous trastuzumab treatment.Due to limited real-world data,we evaluate the effectiveness of anti-human ep... Objective:Several studies have demonstrated different benefits for patients whose disease progressed despite previous trastuzumab treatment.Due to limited real-world data,we evaluate the effectiveness of anti-human epidermal growth factor receptor 2(HER2)therapy(lapatinib or trastuzumab)plus chemotherapy or chemotherapy alone in patients who were previously treated with trastuzumab-containing regimens and investigate factors associated with effectiveness.And we further show the effectiveness of the two anti-HER2 therapy groups.Methods:A total of 342 HER2-positive metastatic breast cancer(MBC)patients whose disease progressed during prior anti-HER2(trastuzumab)and standard chemotherapy therapy from Department of Breast Oncology,the Fifth Medical Center of Chinese PLA General Hospital,from August 2010 to December 2016 were included.Seventy-eight patients received standard chemotherapy only,148 patients continued to receive trastuzumab and switched to other chemotherapy drugs,and 116 patients received tyrosine-kinase inhibitors(TKIs;lapatinib)and chemotherapy.The main outcome measures were progression-free survival(PFS),overall response rate(ORR),and clinical benefit rate(CBR).Subgroup analyses were conducted to identify patient characteristics associated with the greatest clinical benefit.Results:After a median follow-up of 26.2(range,2.0-56.0)months,PFS significantly improved with anti-HER2 therapy compared with chemotherapy alone:median 6.0 months with lapatinib[95%confidence interval(95%CI),4.53-7.47],4.5 months with trastuzumab(95%CI,3.99-5.01)vs.3.0 months with chemotherapy alone(95%CI,2.42-3.58);stratified hazard ratio(HR)=0.70,95%CI,0.60-0.81;P<0.0001.The ORR values were 33.6%,25.0%and 12.8%,respectively,the CBR values were 60.3%,48.6%and 26.9%,respectively.The effectiveness of lapatinib group and trastuzumab group were further analyzed.In multivariate analysis,lapatinib group was associated with a longer PFS,after controlling other potential confounders(HR=0.68,95%CI,0.52-0.90;P=0.006).Conclusions:The combination of TKIs and chemotherapy was effective in this cohort previously treated with trastuzumab treatment.Therefore,TKIs combined with chemotherapy is an option for Chinese HER2-positive MBC patients previously treated with trastuzumab treatment. 展开更多
关键词 Metastatic breast cancer trastuzumab failure SECOND-LINE real-world study
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Preparation of Nano-Sized TiO_2 Particles by Microemulsion Method 被引量:1
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作者 shaohua zhang Bing Xie +1 位作者 Fengyi Li Peng Xu 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期575-577,共3页
Nano-sized titania powders have been prepared by hydrolysis of tetrabutyl titanate in the droplet of water/OP-7/pentanol/cyclohexane microemulsion system.The effects of ingredient change on the water drop size and par... Nano-sized titania powders have been prepared by hydrolysis of tetrabutyl titanate in the droplet of water/OP-7/pentanol/cyclohexane microemulsion system.The effects of ingredient change on the water drop size and particle size were investigated.The prepared TiO_2 was in the form of anatase after annealing.TiO_2 was characterized by TG-TGA, FTIR,XRD to measure the transformation temperature,surface adsorption and average size. 展开更多
关键词 TIO2 MICROEMULSION NANO
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财政支出预期冲击——来自金融市场的识别
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作者 田磊 张少华 张佐敏 《经济学报》 CSSCI 2022年第3期120-157,共38页
公众对财政政策的预期是否具有重要的宏观经济效应?为探究这一问题,本文首先分析了财政支出预期对宏观经济动态系统和SVAR设定的影响;接着,基于中国财政政策实践和股市运行特征,构造适合中国财政政策实践的财政政策预期变量;最后,建立S... 公众对财政政策的预期是否具有重要的宏观经济效应?为探究这一问题,本文首先分析了财政支出预期对宏观经济动态系统和SVAR设定的影响;接着,基于中国财政政策实践和股市运行特征,构造适合中国财政政策实践的财政政策预期变量;最后,建立SVAR模型,识别出财政支出预期冲击效应和未预期到的财政支出冲击效应。研究发现:(1)本文基于上证180基建指数季度简单超额收益率构造的财政支出预期变量,对政府投资支出和总财政支出具有良好的预测能力;财政支出预期冲击能够产生明显的宏观经济刺激效应。(2)不含财政政策预期变量的SVAR模型将不同程度地高估主要宏观经济变量的脉冲响应函数。(3)未预期到的政府投资并不拥有明显高于政府消费的支出乘数。本文最主要的边际学术贡献是构建了一个适用于中国数据的财政支出预期的代理变量。 展开更多
关键词 财政支出预期 季度简单超额收益率 SVAR 财政支出乘数
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Effect of Microstructure on Electrorheological Property for Pure TiO_(2) Particle Material
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作者 Yanli SHANG Shuzhen MA +3 位作者 Junran LI Mingxiu LI Juan WANG shaohua zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第4期572-576,共5页
Pure titanium dioxide (TiO2) particle materials were prepared by hydrolyzing titanium tetrachloride (TiCl4). The microstructures of these materials were determined by X-ray diffraction (XRD), accelerated surface... Pure titanium dioxide (TiO2) particle materials were prepared by hydrolyzing titanium tetrachloride (TiCl4). The microstructures of these materials were determined by X-ray diffraction (XRD), accelerated surface area and porosimetry apparatus (BET), and transmission electron microscopy (TEM). The TiO2 materials obtained by calcinations under different temperatures distinctly revealed different microstructures in crystal structure type, surface area, pore size, pore volume and grain size. The relationship between the microstructure of the TiO2 materials and their electrorheological (ER) activity was investigated. Anatase titania particles have better ER performance than rutile titania particles. Amorphous TiO2 materials display higher ER activity than the crystalline titania materials. A large pore volume can be more advantageous in improving the ER effect of a particle material. 展开更多
关键词 Titanium dioxide TEMPERATURE MICROSTRUCTURE Electrorheolagical property
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A novel extradural nerve transfer technique by coaptation of C4 to C5 and C7 to C6 for treating isolated upper trunk avulsion of the brachial plexus
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作者 Kaixiang Yang shaohua zhang +3 位作者 Dawei Ge Tao Sui Hongtao Chen Xiaojian Cao 《The Journal of Biomedical Research》 CAS CSCD 2018年第4期298-304,共7页
The study aimed to demonstrate the feasibility of an extradural nerve anastomosis technique for the restoration of a C5 and C6 avulsion of the brachial plexus.Nine fresh frozen human cadavers were used.The diameters,s... The study aimed to demonstrate the feasibility of an extradural nerve anastomosis technique for the restoration of a C5 and C6 avulsion of the brachial plexus.Nine fresh frozen human cadavers were used.The diameters,sizes,and locations of the extradural spinal nerve roots were observed.The lengths of the extradural spinal nerve roots and the distance between the neighboring nerve root outlets were measured and compared in the cervical segments.In the spinal canal,the ventral and dorsal roots were separated by the dura and arachnoid.The ventral and dorsal roots of C7 had sufficient lengths to anastomose those of C6.The ventral and dorsal of C4 had enough length to be transferred to those of C5,respectively.The feasibility of this extradural nerve anastomosis technique for restoring C5 and C6 avulsion of the brachial plexus in human cadavers was demonstrated in our anatomical study. 展开更多
关键词 brachial plexus nerve transfer spinal nerve roots extradural anastomosis surgical feasibility study
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Low Temperature Direct Synthesis of Strontium Titanate Powder
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作者 Bing Xie shaohua zhang +1 位作者 Fengyi Li Yumei Wu 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期556-558,共3页
Low temperature direct synthesis (LTDS) involves the preparation of a base solution of Sr^(2+),and the mixing of base solution with tetrabutyl titanate solution.LTDS is an advantageous method because it does not requi... Low temperature direct synthesis (LTDS) involves the preparation of a base solution of Sr^(2+),and the mixing of base solution with tetrabutyl titanate solution.LTDS is an advantageous method because it does not require the complex hydrothermal facilities and it can prevent the agglomeration in calcinations of other liquid methods.In our work,we adopted LTDS method to prepare the nano strontium titanate powders,and characterize them by XRD,FT-IR and TGA.The influences of preparation temperature and solvents on grain size and lattice parameters were investigated.The results show that preparation temperature can slightly change the lattice parameters of grain,while solvents also play important roles in the preparation. 展开更多
关键词 SRTIO3 low temperature direct synthesis nano powder
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Rules of Pesticide Use for Food Crop Diseases and Pests: A Concise Diagram Based on Correspondence Analysis
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作者 Xiaojie YANG shaohua zhang +2 位作者 Weizheng LI Huaisen XING Guohui YUAN 《Agricultural Biotechnology》 CAS 2022年第5期57-64,71,共9页
In order to ensure food security, the selection of pesticide must take into account the controlling effect and economy in the chemical control of food crop diseases and pests. Although China has registered a large num... In order to ensure food security, the selection of pesticide must take into account the controlling effect and economy in the chemical control of food crop diseases and pests. Although China has registered a large number of pesticides and fungicides on food crops, traditional statistical methods cannot treat the complex relationships between crops, pests and diseases, as well as pesticides. To this end, the correspondence analysis was used to mine the data of pesticides being registered after January 1, 2010 for the prevention and control of pests and diseases on wheat, corn, and rice in China, in order to reveal the general rules of pesticide use for the prevention and control of grain crop pests and diseases and to provide scientifically recommended pesticide regimens.(1) Recommended pesticides for wheat diseases and pests: For underground pest control, phoxim, diazinon or clothianidin is recommended;imidacloprid is recommended for aphid control;avermectin is recommended for mite control;chlorpyrifos is recommended for midge control;the pesticides for rust control could be selected according to the order of epoxiconazole>flutriafol>kresoxim-methyl>cyproconazole≈hexaconazole;tebuconazole is recommended for the prevention and control of smut;difenoconazole is recommended for the simultaneous occurrence of take-all, smut and sheath blight;it is recommended to use carbendazim or thiophanate-methyl for the control of scab;and triazolone or pyraclostrobin is recommended for the control of powdery mildew.(2) Recommended pesticides for corn diseases and pests: For the control of underground pests, fipronil, carbosulfan or chlorpyrifos are recommended;thiamethoxam is recommended for control of planthoppers and corn aphids;Bacillus thuringiensis or phoxim is recommended for control of corn borers;pyraclostrobin is recommended for the control of northern leaf blight;tebuconazole is recommended for the control of head smut;and fludioxonil+metalaxyl-M is recommended for the control of corn stalk rot.(3) Recommended pesticides for rice diseases and pests: It is recommended to use triazophos, avermectin analogs or methoxyfenozide for the control of borers;for rice planthoppers, the pesticides could be selected in order of pymetrozine>imidacloprid>thiamethoxam>thiazide>nitenpyram;avermectin analogs are recommended for the control of rice leaf rollers;tebuconazole is recommended for the control of rice false smut;prochloraz and its manganese salts are recommended for the control of bakanae disease;hymexazol is recommended for the control of wilt disease;thifluzamide or hexaconazole is recommended for the control of sheath blight;and the pesticides for the control of rice blast are in order of tricyclazole>kasugamycin>fenoxanil>isoprothiolane>Bacillus subtilis. In addition, potential applications of correspondence analysis in other fields of plant protection are discussed. 展开更多
关键词 Food crop Wheat CORN Rice FUNGICIDE PESTICIDE Correspondence analysis Pesticide use rules
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Text Feature Extraction and Classification Based on Convolutional Neural Network(CNN)
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作者 Taohong zhang Cunfang Li +3 位作者 Nuan Cao Rui Ma shaohua zhang Nan Ma 《国际计算机前沿大会会议论文集》 2017年第1期119-121,共3页
With the high-speed development of the Internet,a growing number of Internet users like giving their subjective comments in the BBS,blog and shopping website.These comments contains critics’attitudes,emotions,views a... With the high-speed development of the Internet,a growing number of Internet users like giving their subjective comments in the BBS,blog and shopping website.These comments contains critics’attitudes,emotions,views and other information.Using these information reasonablely can help understand the social public opinion and make a timely response and help dealer to improve quality and service of products and make consumers know merchandise.This paper mainly discusses using convolutional neural network(CNN)for the operation of the text feature extraction.The concrete realization are discussed.Then combining with other text classifier make class operation.The experiment result shows the effectiveness of the method which is proposed in this paper. 展开更多
关键词 Convolutional NEURAL network(CNN) TEXT FEATURE EXTRACTION CLASS operation
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一种通用静电组装策略用于印刷无机纳米颗粒及其在大面积钙钛矿太阳电池中的应用
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作者 李文杰 褚昭阳 +9 位作者 李豪杰 李丰 邢直 范宝锦 孟祥川 余德见 梁超 章少华 胡笑添 陈义旺 《Science China Materials》 SCIE EI CAS CSCD 2024年第5期1602-1611,共10页
无机纳米颗粒作为一种极具前景的材料,在钙钛矿太阳电池的传输层中得到了广泛应用.然而,无机纳米颗粒易于聚集的特性阻碍了其进一步的发展.在大面积制备过程中,无机纳米颗粒的聚集加剧了“咖啡环效应”,导致薄膜不均匀,使得底部界面性... 无机纳米颗粒作为一种极具前景的材料,在钙钛矿太阳电池的传输层中得到了广泛应用.然而,无机纳米颗粒易于聚集的特性阻碍了其进一步的发展.在大面积制备过程中,无机纳米颗粒的聚集加剧了“咖啡环效应”,导致薄膜不均匀,使得底部界面性能较差,进而影响钙钛矿薄膜的结晶,最终导致整个器件性能下降.为解决这一问题,我们将一种带电聚合物一一聚乙烯亚胺引入至无机纳米颗粒溶液中.聚乙烯亚胺的带电性质对无机纳米颗粒的聚集起到了显著的抑制作用,此外,添加聚乙烯亚胺还增加了无机纳米颗粒溶液的粘度,有助于减少薄膜上的负面咖啡环效应.最终,我们在基于1-cm^(2)正式结构且使用SnO_(2)传输层的器件上实现了23.2%的光电转换效率.为进一步证明这一策略的普适性,我们还将此策略验证基于NiO_(x)传输层的1-cm^(2)反式器件,其转换效率超过20%. 展开更多
关键词 perovskite solar cells inorganic nanoparticles large-area device electrostatic assembly technique
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Erratum to “Lipidome Atlas of the Developing Heart Uncovers Dynamic Membrane Lipid Attributes Underlying Cardiac Structural and Metabolic Maturation”
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作者 Huan Miao Bowen Li +7 位作者 Zehua Wang Jinming Mu Yanlin Tian Binhua Jiang shaohua zhang Xia Gong Guanghou Shui Sin Man Lam 《Research》 SCIE EI CSCD 2024年第1期825-826,共2页
Main Text In the Research Article“Lipidome Atlas of the Developing Heart Uncovers Dynamic Membrane Lipid Attributes Underlying Cardiac Structural and Metabolic Maturation”[1],there was an error in Fig.2B.The authors... Main Text In the Research Article“Lipidome Atlas of the Developing Heart Uncovers Dynamic Membrane Lipid Attributes Underlying Cardiac Structural and Metabolic Maturation”[1],there was an error in Fig.2B.The authors mistakenly repeated the chord diagram designated for P7 with that from P1.The figure amendment did not affect the in-text discussion of the figure,which was focused on changes between P0 and P21,and did not alter the conclusion.Figure 2B has now been corrected in the PDF and HTML(full text). 展开更多
关键词 ATLAS Dynamic HTML
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Efficacy and clinical outcome of chemotherapy and endocrine therapy as first-line treatment in patients with hormone receptor-positive HER2-negative metastatic breast cancer 被引量:2
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作者 Yang Yuan shaohua zhang +7 位作者 Tao Wang Li Bian Min Yan Yongmei Yin Yuhua Song Yi Wen Jianbin Li Zefei Jiang 《Chinese Medical Journal》 SCIE CAS CSCD 2023年第12期1459-1467,共9页
Background:Endocrine therapy(ET)and ET-based regimens are the preferred first-line treatment options for hormone receptor(HR)-positive and human epidermal growth factor receptor 2(HER2)-negative metastatic breast canc... Background:Endocrine therapy(ET)and ET-based regimens are the preferred first-line treatment options for hormone receptor(HR)-positive and human epidermal growth factor receptor 2(HER2)-negative metastatic breast cancer(HR+/HER2-MBC),while chemotherapy(CT)is commonly used in clinical practice.The aim of this study was to investigate the efficacy and clinical outcome of ET and CT as first-line treatment in Chinese patients with HR+/HER2-MBC.Methods:Patients diagnosed with HR+/HER2-MBC between January 1st,1996 and September 30th,2018 were screened from the Chinese Society of Clinical Oncology Breast Cancer database.The initial and maintenance first-line treatment,progression-free survival(PFS),and overall survival(OS)were analyzed.Results:Among the 1877 included patients,1215(64.7%)received CT and 662(35.3%)received ET as initial first-line treatment.There were no statistically significant differences in PFS and OS between patients receiving ET and CT as initial first-line treatment in the total population(PFS:12.0 vs.11.0 months,P=0.22;OS:54.0 vs.49.0 months,P=0.09)and propensity score matched population.For patients without disease progression after at least 3 months of initial therapy,maintenance ET following initial CT(CT-ET cohort,n=449)and continuous schedule of ET(ET cohort,n=527)had longer PFS than continuous schedule of CT(CT cohort,n=406)in the total population(CT-ET cohort vs.CT cohort:17.0 vs.8.5 months;P<0.01;ET cohort vs.CT cohort:14.0 vs.8.5 months;P<0.01)and propensity score matched population.OS in the three cohorts yielded the same results as PFS.Conclusions:ET was associated with similar clinical outcome to CT as initial first-line treatment.For patients without disease progression after initial CT,switching to maintenance ET showed superiority in clinical outcome over continuous schedule of CT. 展开更多
关键词 Breast neoplasms Metastatic breast cancer Hormone receptor-positive HER2-negative CHEMOTHERAPY Endocrine therapy First-line treatment Maintenance therapy
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Mesozoic Tectonothermal Evolution of the Southern Central Asian Orogenic Belt: Evidence from Apatite Fission-Track Thermochronology in Shalazha Mountain, Inner Mongolia 被引量:1
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作者 Heng Peng Jianqiang Wang +5 位作者 Chiyang Liu shaohua zhang Yazhuo Niu Tianbing zhang Bo Song Wei Han 《Journal of Earth Science》 SCIE CAS CSCD 2023年第1期37-53,共17页
Mesozoic intracontinental orogeny and deformation were widespread within the southern Central Asian Orogenic Belt(CAOB). Chronological constraints remain unclear when assessing the Mesozoic evolution of the central se... Mesozoic intracontinental orogeny and deformation were widespread within the southern Central Asian Orogenic Belt(CAOB). Chronological constraints remain unclear when assessing the Mesozoic evolution of the central segment of this region. The tectonic belt of Shalazha Mountain located in the center of this region is an ideal place to decode the deformation process. Apatite fission-track(AFT) thermochronology in Shalazha Mountain is applied to constrain the Mesozoic tectonothermal evolution of the central segment of southern CAOB. The bedrock AFT ages range from 161.8 ± 6.9 to 137.0 ± 7.3 Ma, and the first reported detrital AFT obtained from Lower Cretaceous strata shows three age peaks: P1(ca. 178 Ma), P2(ca. 149 Ma) and P3(ca. 105.6 Ma). Bedrock thermal history modeling indicates that Shalazha Mountain have experienced three stages of differential cooling: Late Triassic–Early Jurassic(~230–174 Ma), Late Jurassic–Earliest Cretaceous(~174–135 Ma) and later(~135 Ma). The first two cooling stages are well preserved by the detrital AFT thermochronological result(P1, P2) from the adjacent Lower Cretaceous strata, while P3(ca. 105.6 Ma) records coeval volcanic activity. Furthermore, our data uncover that hanging wall samples cooled faster between the Late Triassic and the Early Cretaceous than those from the footwall of Shalazha thrust fault, which synchronizes with the cooling of the Shalazha Mountain and implies significant two-stage thrust fault activation between ca. 230 and 135 Ma. These new low-temperature thermochronological results from the Shalazha Mountain region and nearby reveal three main phases of differential tectonothermal events representing the Mesozoic reactivation of the central segment of the southern CAOB. In our interpretations, the initial rapid uplift in the Late Triassic was possibly associated with intracontinental orogenesis of the CAOB. Subsequent Middle Jurassic–Earliest Cretaceous cooling is highly consistent with the Mesozoic intense intraplate compression that occurred in the southern CAOB, and is interpreted as a record of closure of the Mongol-Okhotsk Ocean. Then widespread Cretaceous denudation and burial in the adjacent fault basin could be linked with the oblique subduction of the Izanagi Plate along the eastern Eurasian Plate, creating a northeast-trending normal fault and synchronous extension. However, our AFT thermochronometry detects no intense Cenozoic reactivation information of Shalazha Mountain region. 展开更多
关键词 intracontinental deformation Shalazha Mountain southern Central Asian Orogenic Belt APATITE apatite fission-track thermal history modeling EXHUMATION
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