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Three-dimensional ultrasound subwavelength arbitrary focusing with broadband sparse metalens

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Science China(Physics,Mechanics & Astronomy) 2022年第2期65卷 50-56页

作者： Xue Jiang JiaJie He chuanxin zhang HuaLiang Zhao WeiQi Wang DeAn Ta Cheng-Wei Qiu Center for Biomedical Engineering School of Information Science and TechnologyFudan UniversityShanghai 200433China Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore

Ultrasound focusing in three-dimensional(3 D)space is of crucial and enduring significance in a variety of biomedical and industrial *** ultrasound focusing based on active phase array or passive geometry of bulky size is unable to realize the 3 D arbitrary focusing with subwavelength *** metamaterial of complex deep-subwavelength microstructure has facilitated the advanced airborne-sound-focusing but is inevitably not applicable for underwater ultrasound,restricted by the law between the multi-modes coupling/thermal viscosity and the feature size of the ***,we aim to circumvent the restriction by increasing the feature size of the metamaterial while keeping the compact overall geometry,and realize the robust subwavelength ultrasound focusing with the sparse metalens of the wavelength-scale *** theoretically propose and demonstrate numerically and experimentally the broadband arbitrary ultrasound focusing in 3 D *** axial and off-axis ultrasound focusing with the subwavelength resolution(FWHM<0.58λ)are achieved by the spatially sparse and compact metalens within one-octave *** advantages of 3 D freewheeling focusing,subwavelength resolution,spatial sparsity,geometric simplicity,and broadband,the sparse metalens would offer more initiatives to advanced researches in ultrasound focusing and empower applications such as precise biomedical imaging and therapy,nondestructive evaluation,integrated and multiplexed ultrasound devices.

关键词： broadband ultrasound focusing sparse metalens subwavelength resolution three-dimensional focusing

Plasmonic coupling-enhanced in situ photothermal nanoreactor with shape selective catalysis for C–C coupling reaction

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Nano Research 2020年第10期13卷 2812-2818页

作者： Zhenxing Li Yixuan Gong Xin zhang Yangyang Wen Jiasai Yao Mingliang Hu Miao He Jiahao Liu Rui Li Fuqiang Wang chuanxin zhang Key Laboratory of Heary Oil Processing College of New Energy and MaterialsBeijing Key Laboratory of Biogas Upgrading UtilizationChina Universily of Petroleum(Beijing)Beijing 102249China School of New Energy Harbin Institute of Technology at Weihai2 West Wenhua RoadWeihai 264209China

Carbon-carbon(C–C)coupling reactions represent one of the most powerful tools for the synthesis of complex natural products,bioactive molecules developed as drugs and *** this work,a multifunctional nanoreactor for C–C coupling reaction was successfully fabricated via encapsulating the core-shell Cu@Ni nanocubes into ZIF-8(Cu@Ni@ZIF-8).In this nanoreactor,Ni shell of the core-shell Cu@Ni nanocubes was the catalytical active center,and Cu core was in situ heating source for the catalyst by absorbing the visible ***,benefiting from the plasmonic resonance effect between Cu@Ni nanocubes encapsulated in ZIF-8,the absorption range of nanoreactor was widened and the utilization rate of visible light was *** importantly,the microporous structure of ZIF-8 provided shape-selective of *** composite was used for the highly shape-selective and stable photocatalysed C–C coupling reaction of boric acid under visible light *** five cycles,the nanoreactor still remained high catalytical *** Cu@Ni@ZIF-8 nanoreactor opens a way for photocatalytic C–C coupling reactions with shape-selectivity.

关键词： nanoreactor metal-organic framework photocatalysis shape selective catalysis C–C coupling reaction

The Influence and Treatment of the Intestinal Microbiome on Child Respiratory Diseases

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Infectious Microbes & Diseases 2020年第3期2卷 107-114页

作者： chuanxin zhang Junlin Huang Yifan Ren Shenghong Zhu Fangxue Yin Yixin Zhu Shaoxin Keqiao Women&Children's Hospital ShaoxingZhejiangChina College of Pharmacy University of MichiganAnn ArborMichiganUSA Shulan International Medical College Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren UniversityHangzhouZhejiangChina

The intestinal microbiome has a great influence on human health through its close interaction with the human body,including growth,development,maturation,immunity,and *** studies have reported that the intestinal microbiome is related to the pathogenesis,diagnosis,and treatment of *** clinical interventions,such as prebiotics and probiotics have been widely used to cure ***,probiotics might suffer from viability ***,new technologies are being exploited to solve these *** this review,we describe the correlation between the intestinal microbiome and children respiratory diseases,present therapies based on microecological theory,and introduce some new technologies aimed to improve the efficacy of microbiological therapies.

关键词： microbiota pediatric respiratory disease probiotics fecal microbiota transplantation

Allelic reprogramming of chromatin states in human early embryos

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National Science Review 2024年第3期11卷 58-71页

作者： Shenli Yuan Lei Gao Wenrong Tao Jianhong Zhan Gang Lu Jingye zhang chuanxin zhang Lizhi Yi Zhenbo Liu Zhenzhen Hou Min Dai Han Zhao Zi-Jiang Chen Jiang Liu Keliang Wu Center for Reproductive Medicine Shandong University CAS Key Laboratory of Genome Sciences and Information Collaborative Innovation Center of Genetics and Development Beijing Institute of Genomicsand China National Center for BioinformationChinese Academy of Sciences University of Chinese Academy of Sciences CUHK-SDU Joint Laboratory on Reproductive Genetics School of Biomedical Sciences the Chinese University of Hong Kong Key Laboratory of Reproductive Endocrinology of the Ministry of Education Shandong University Center for Reproductive Medicine Ren Ji Hospital School of Medicine Shanghai Jiao Tong University CAS Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences

The reprogramming of parental epigenomes in human early embryos remains elusive. To what extent the characteristics of parental epigenomes are conserved between humans and mice is currently unknown. Here,we mapped parental haploid epigenomes using human parthenogenetic and androgenetic embryos. Human embryos have a larger portion of genome with parentally specific epigenetic states than mouse *** allelic patterns of epigenetic states for orthologous regions are not conserved between humans and mice. Nevertheless, it is conserved that maternal DNA methylation and paternal H3K27me3 are associated with the repression of two alleles in humans and mice. In addition, for DNA-methylation-dependent imprinting, we report 19 novel imprinted genes and their associated germline differentially methylated regions. Unlike in mice, H3K27me3-dependent imprinting is not observed in human early ***, allele-specific epigenomic reprogramming is different in humans and mice.

关键词： human embryo epigenetics reprogramming DNA methylation H3K27me3 chromatin accessibility

M(OTf)_3催化N-烷氧羰基吡咯或噻吩与甲醛和盐酸伯胺的新颖Mannich反应

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化学学报 2002年第3期60卷 481-486页

作者：张传新程铁明李润涛北京大学药学院北京100083

三氟甲磺酸盐M(OTf) 3 (M =Sc,Y ,Ln)在水相中能较好地催化N 烷氧羰基吡咯或噻吩与甲醛和盐酸伯胺的新颍的Mannich反应 ,其中Y(OTf) 3 催化效果最佳 .该反应具有条件温和 ,收率较高和原子经济性等优点 ,为N 烷氧羰基吡咯和噻吩类Mannic... 详细信息

三氟甲磺酸盐M(OTf) 3 (M =Sc,Y ,Ln)在水相中能较好地催化N 烷氧羰基吡咯或噻吩与甲醛和盐酸伯胺的新颍的Mannich反应 ,其中Y(OTf) 3 催化效果最佳 .该反应具有条件温和 ,收率较高和原子经济性等优点 ,为N 烷氧羰基吡咯和噻吩类Mannich碱的合成提供了一种新方法 ,同时该反应以水为主要溶剂 ,符合当今绿色化学的发展趋势 .

关键词： M(OTf)3 N-烷氧羰基吡咯噻吩盐酸伯胺 Mannich反应催化剂三氟甲磺酸盐曼尼希反应

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地方政府绩效评估信息失真的成因及其治理

中州学刊 2006年第6期 41-43页

作者：张创新芦刚吉林大学行政学院吉林长春130012

政府绩效评价是一种有效的政府管理手段和工具,对促进政府转变行政理念、提高工作效率和公共服务质量、控制行政成本等有重要作用。如何开展科学、有效的政府绩效评价是目前学术界和实践界都很为关心的问题。为此,本刊特别选发了两篇文... 详细信息

政府绩效评价是一种有效的政府管理手段和工具,对促进政府转变行政理念、提高工作效率和公共服务质量、控制行政成本等有重要作用。如何开展科学、有效的政府绩效评价是目前学术界和实践界都很为关心的问题。为此,本刊特别选发了两篇文章,以期把有关地方政府绩效评价问题的研究引向深入。

关键词：政府绩效评估评价问题信息失真政府绩效评价治理成因公共服务质量政府管理

交变电磁场与超声波对硬水溶液及其结晶的影响

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化工学报 2018年第4期69卷 1620-1630页

作者：张传鑫韩勇朱琳赵瑞宽吴会帆河北省测试计量技术及仪器重点实验室燕山大学电气工程学院河北秦皇岛066004 河北省应用化学重点实验室燕山大学环境与化学工程学院河北秦皇岛066004

实验研究了交变电磁场、超声波及二者协同作用对硬水溶液pH及电导率的影响,并对实验过程中溶液内析出的碳酸钙晶体表面形态及晶体组成进行了观测与研究。研究结果表明:交变电磁场与超声波都能影响Ca(HCO_3)_2溶液内的离子水解平衡;交变... 详细信息

实验研究了交变电磁场、超声波及二者协同作用对硬水溶液pH及电导率的影响,并对实验过程中溶液内析出的碳酸钙晶体表面形态及晶体组成进行了观测与研究。研究结果表明:交变电磁场与超声波都能影响Ca(HCO_3)_2溶液内的离子水解平衡;交变电磁场能提升正、负离子的碰撞概率,促进CaCO_3晶体成核并抑制其体积增长;超声波能够促使CaCO_3沉淀的生成,同时增大溶液内离子的迁移速率,破坏晶体内碳酸根排列的有序性,诱导CaCO_3晶体缺陷性生长;通过SEM对最终生成的晶体形态观测可知,交变电磁场与超声波协同作用能够增加CaCO_3小尺寸晶体的数量,并抑制晶体体积生长,且能增加霰石在沉淀中的比例。

关键词： pH 电导率水解成核粒度分布 SEM

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移动自组织网络预测分簇算法的路由协议

电视技术 2014年第11期38卷 97-102页

作者：陶洋李超张传欣重庆邮电大学通信软件技术研究所重庆400065

针对移动自组织网络中传统分簇算法存在稳定性低、网络开销大的问题,在WCA分簇算法的基础上,提出一种带有预测机制的EWCA-MP(Efficient on-demand Weighted Clustering Algorithm using Mobility Prediction)分簇算法,该算法在簇头选择... 详细信息

针对移动自组织网络中传统分簇算法存在稳定性低、网络开销大的问题,在WCA分簇算法的基础上,提出一种带有预测机制的EWCA-MP(Efficient on-demand Weighted Clustering Algorithm using Mobility Prediction)分簇算法,该算法在簇头选择时充分考虑节点间的链路保持时间,在簇维护阶段引入模糊逻辑的概念,对Hello消息包的广播周期进行优化。并将其应用于CBRP中,提出了一种ECBRP-MP(Efficient Cluster Based Routing Protocol using Mobility Prediction)移动预测的分簇路由协议。仿真结果表明,EWCA-MP算法在簇头数目、单位时间内节点转移次数和统治集更新次数明显减少,ECBRP-MP路由协议在路由开销、分组投递率的性能得到优化。

关键词：移动自组网分簇算法分级路由协议预测

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构造应力场对深井巷道围岩稳定的影响

金属矿山 2005年第5期34卷 21-23,59页

作者：赵继银张传信中钢集团马鞍山矿山研究院

为了研究构造应力场对深井巷道围岩稳定的影响,运用3D-σ有限元计算软件对深井巷道在构造应力场中不同布置方向的稳定性进行了数值模拟分析,分析得出随着巷道轴向与构造应力场方向夹角的增大,巷道围岩受力状况逐渐趋于恶化。对此,提出... 详细信息

为了研究构造应力场对深井巷道围岩稳定的影响,运用3D-σ有限元计算软件对深井巷道在构造应力场中不同布置方向的稳定性进行了数值模拟分析,分析得出随着巷道轴向与构造应力场方向夹角的增大,巷道围岩受力状况逐渐趋于恶化。对此,提出在布置巷道时,尽可能使巷道轴线方向与最大水平主应力方向以小角度相交(最好趋于一致),并采用宽度大于高度的矩形、拱形或椭圆形断面,使断面形状与构造应力状态相适应。

关键词：构造应力场深井巷道围岩稳定有限元计算软件数值模拟分析主应力方向布置方向受力状况巷道围岩圆形断面应力状态断面形状稳定性小角度拱形