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Special topic on research frontiers in porous organic polymers

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Science China Chemistry 2017年第8期60卷 997-998页

作者： bao-hang han Dong Wang National Center for Nanoscience and Technology Beijing 100190China Institute of Chemistry Chinese Academy of SciencesBeijing 100190China

Porous organic polymers(POPs)are materials with covalently bonded,thermally stable backbones that exhibit large accessible surface areas and intriguing properties applicable to fields such as gas storage and separation,catalysis,and *** to analogous inorganic porous materials,POPs feature a wider range of pore size,larger surface area,readily available functional groups for post-synthesis functionalization,etc.,which enables their design for targeted applications.

关键词：有机聚合物多孔材料持久性有机污染物专题 POPs 表面积热稳定官能团

昭通市农田土壤和蔬菜重金属污染评价及相关性分析

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环境科学 2024年第2期45卷 1090-1097页

作者：张好董春雨杨海婵孙思静韩宇黄祖志张乃明包立云南农业大学资源与环境学院昆明650201 云南省土壤培肥与污染修复工程研究中心昆明650201

以昭通市农田区域为研究对象,采用点对点协同采样的方法对昭通市农田土壤和蔬菜进行采集,测定了As、Pb、Cu、Zn、Cd和Cr这6种重金属含量.使用地累积指数和潜在生态风险指数对土壤重金属污染进行评价,利用健康风险模型评估蔬菜对人体产... 详细信息

以昭通市农田区域为研究对象,采用点对点协同采样的方法对昭通市农田土壤和蔬菜进行采集,测定了As、Pb、Cu、Zn、Cd和Cr这6种重金属含量.使用地累积指数和潜在生态风险指数对土壤重金属污染进行评价,利用健康风险模型评估蔬菜对人体产生的风险情况.结果表明,研究区土壤存在Cu、Zn、Pb、Cd和Cr污染,相较于农用地风险筛选值,超标率分别为34.35%、6.87%、2.2.%、80.15%和6.11%;蔬菜存在Pb、Cd和Cr污染,相较于食品中污染物限量,超标率分别为6.87%、15.2.%和36.64%.土壤污染评价表明,土壤重金属Cd存在强生态风险,其余重金属存在轻微生态风险.人体健康风险评估模型显示,非致癌风险及致癌风险均超过可接受范围,且对儿童的影响更大.相关性分析表明,土壤中的As对蔬菜吸收Cu和Zn具有拮抗作用,而土壤中Cr对蔬菜吸收Cu和Zn具有促进作用.

关键词：农田土壤重金属蔬菜健康风险评价相关性

固溶温度对S32.50双相不锈钢低周疲劳性能的影响

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钢铁研究学报 2024年第2期36卷 217-225页

作者：保顺丰涵宋志刚何建国顾洋钢铁研究总院有限公司特殊钢研究院北京100081

通过OM观察、电子背散射衍射技术、显微硬度测试、拉伸及疲劳试验研究了5种固溶温度试验钢的组织形态及低周疲劳性能。结果表明,当固溶温度由1050℃升至1180℃时,试验钢屈服强度与抗拉强度分别提升41、31.5 MPa,低周疲劳寿命延长85%。... 详细信息

通过OM观察、电子背散射衍射技术、显微硬度测试、拉伸及疲劳试验研究了5种固溶温度试验钢的组织形态及低周疲劳性能。结果表明,当固溶温度由1050℃升至1180℃时,试验钢屈服强度与抗拉强度分别提升41、31.5 MPa,低周疲劳寿命延长85%。随着固溶温度的升高,试验钢中α相含量由46.5%升至58.9%,也导致两相内主元素发生再分配,α相内Ni、N含量的增加,使其显微硬度由300提升至32.,这是试验钢疲劳寿命提高的原因之一;其二,随着固溶温度的升高,α相内的局部取向差减小,使α相在循环过程中能承受更多载荷,进而提高试验钢低周疲劳寿命。

关键词： S32.50双相不锈钢相比例强度固溶温度低周疲劳性能

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宋代财政复合单位考释

史学月刊 2024年第9期 43-51页

作者：包伟民浙大城市学院浙江历史研究中心浙江杭州310015

宋人往往将各种不同内容与价值的钱物数据简单相加,得出一个“贯石匹两”式的复合性单位,用以描述财政收支情况。此类现象在北宋文献记载中大量存在,令后人费解。要解决这一问题,应该跳出财政核算的传统思路来理解这种文本。受实物财政... 详细信息

宋人往往将各种不同内容与价值的钱物数据简单相加,得出一个“贯石匹两”式的复合性单位,用以描述财政收支情况。此类现象在北宋文献记载中大量存在,令后人费解。要解决这一问题,应该跳出财政核算的传统思路来理解这种文本。受实物财政体系影响,复合单位现象早就存在。汉代常有财政开支“巨万”钱币的记载,那不过是为了表达一种意象,不一定为实数。宋代常见的财政复合单位也正是这样,是表达财政统计总额的一种“说法”或“写法”,而不是实际的财务“算法”。到南宋,财政收支中钱币的比例明显扩大,人们开始倾向于将各种不同物品折算成钱币表述总额,复合单位现象因此减少。元明清时期,随着货币体系日趋统一,仅仅作为一种表述形式的财政复合单位也就更成为人们记忆中的事物了。

关键词：宋代财政数据复合单位贯石匹两实物财政

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基于PT对称的声波超前/延迟线

科学通报 2024年第13期69卷 1794-1802页

作者：张海啸夏一宁廖丹薇刘昕昀刘小利张含鲍彧常州工学院电气信息工程学院常州213032 南京大学物理学院近代声学教育部重点实验室南京210093 常州大学微电子与控制工程学院常州213001

低损耗、长带宽、时间可控的声波延迟线在音频、射频、声表面波信号处理等领域具有非常广泛的应用,然而设计满足上述三点特性的声延迟线是一项极具挑战性的工作.近年来,量子力学中的宇称时间(parity-time,PT)对称概念被引入到声学系统中... 详细信息

低损耗、长带宽、时间可控的声波延迟线在音频、射频、声表面波信号处理等领域具有非常广泛的应用,然而设计满足上述三点特性的声延迟线是一项极具挑战性的工作.近年来,量子力学中的宇称时间(parity-time,PT)对称概念被引入到声学系统中,其散射矩阵在特殊点处的实数本征值揭示了声波在此类系统中可实现宽带的无损传输,且传输相位可调.本文设计了一种由一对PT对称的导纳超表面及夹在中间的等效声学介质组成的声学系统,通过设置导纳超表面参数调节其工作机制,从而实现了两类互补的特殊点.其中防反射层模式下的特殊点导致了一种声波延迟线的形成,而相干完美吸收-激“声”模式下的特殊点则用于设计一种罕见的声波超前线.由于此声学损耗-增益超表面在自然界中是不存在的,本文利用可主动控制的电热声碳纳米管薄膜来模拟它.仿真结果表明,PT对称系统是实现低损耗、长带宽且时间可控的声波超前/延迟线的优良载体,其应用可扩展至包括光学、力学、弹性波等诸多波动领域.

关键词： PT对称声学声学超表面碳纳米管薄膜声波超前/延迟线

A human monoclonal antibody neutralizes SARS-CoV-2.Omicron variants bytargeting the upstream region of spike protein HR2.motif

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hLife 2024年第3期2卷 126-140页

作者： hang Su Jun Zhang Zhenfei Yi Sajid Khan Mian Peng Liang Ye Alan bao han Zhang Guangli Suo Qian Li Housheng Zheng Dandan Wu Thomas J.Kipps Lanfeng Wang Zhenghong Lin Suping Zhang Shenzhen Key Laboratory of Precision Medicine for Hematological Malignancies Guangdong Key Laboratory for Genome Stability andHuman Disease PreventionDepartment of PharmacologySchool of Basic Medical SciencesBase for International Science and TechnologyCooperation:Carson Cancer Stem Cell Vaccines R&D CenterInternational Cancer CenterShenzhen University Medical SchoolShenzhenUniversityGuangdongChina School of Life Sciences Chongqing UniversityChongqingChina The Center for Microbes Development and HealthCAS Key Laboratory of Molecular Virology&ImmunologyShanghai Institute of Immunityand InfectionChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghaiChina College of Life Sciences University of Chinese Academy of SciencesBeijingChina Department of Critical Care Medicine Shenzhen Luohu People’s HospitalGuangdongChina University of California BerkeleyCaliforniaUSA Xenta Biomedical Science Co. LtdGuangdongChina CAS Key Laboratory of Nano-Bio Interface Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesJiangsuChina Center of Novel Therapeutics University of CaliforniaSan DiegoCaliforniaUSA

The continuous emergence of new severe acute respiratory syndrome coronavirus 2.SARS-CoV-2.variants meansthere is a need to explore additional strategies to develop broad-spectrum vaccines or therapeutics for individuals remaining at risk of coronavirus disease 2.19(COVID-19).Neutralizing monoclonal antibody(mAb)that binds to theconserved S2.subunit of the SARS-CoV-2.spike(S)protein alone,or in combination with mAb that binds to the receptor-binding domain(RBD)of S protein,might be effective in eliciting protection from infection by a variety of SARS-CoV2.*** high-throughput single-cell immunoglobulin sequencing of B cells from COVID-19-convalescent donors,we identified a high-affinity S2.specific mAb-39,that could inhibit original SARS-CoV-2.strain,Omicron BA.1,BA.2.86,BA.4,BA.5,and EG.5.1 S protein-mediated membrane fusion,leading to the neutralization of these ***,mAb-39 could also improve the neutralizing activity of anti-RBD antibody against the highlyneutralization-resistant Omicron *** docking and point mutation analyses revealed that mAb-39 recognized epitopes within the conserved upstream region of the heptad repeat 2.HR2.motif of the S2.***,these findings demonstrate that targeting the conserved upstream region of the HR2.motif(e.g.,using mAbs)provides anovel strategy for preventing the infection of SARS-CoV-2.and its variants.

关键词： coronavirus disease 2.19(COVID-19) severe acute respiratory syndrome coronavirus 2.SARS-CoV-2.Omicron variants monoclonal antibody upstream region of heptad repeat 2.HR2. immunoglobulin repertoiresequencing

Editorial for special issue on extraordinary 2.-materials-based nanophotonics

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Chinese Optics Letters 2019年第2期17卷 5-6页

作者： han Zhang Haibo Zeng Qiaoliang {2. Shenzhen University China Nanjing University of Science and Technology China Monash University Australia

The emergence of new materials can push scientific development and even lead to a new industrial revolution. The discovery of graphene has attracted more and more attention from society due to their excellent optics and electricity properties. Graphene has been widely used in optoelectronic devices, such as an optical modulator, polarizer, photoelectric detector, and ultrafast laser. In addition, there is a remarkable transition towards other nanomaterials in recent *** from topological insulators (TIs).

关键词： Editorial special issue 2.-materials-based

Editorial for special issue on photonics based on two-dimensional noncarbon materials

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Chinese Optics Letters 2018年第2期16卷 1-2页

作者： han Zhang Haibo Zeng Qiaoliang {2. Shenzhen University China Nanjing University of Science and Technology China Monash University Australia

Scientists are in the constant search of novel materials,or innovative applications of existing materials to solve problems we face in our everyday *** graphene,the two-dimensional（2.）form of carbon,has been a star player for the past decade,there is a significant shift towards other noncarbon materials in recent *** from the large family of transition metal dichalcogenides（TMDs）,mono-elemental materials,such as phosphorene,arsenene,antimonene.

关键词： Editorial for special issue on photonics based on two-dimensional noncarbon materials

Quantile Regression of Ultra-high Dimensional Partially Linear Varying-coefficient Model with Missing Observations

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数学学报:英文版 2023年第9期39卷 1701-1726页

作者： bao Hua Wang han Ying Liang School of Mathematical Sciences Tongji UniversityShanghai200092P.R.China

In this paper,we focus on the partially linear varying-coefficient quantile regression with missing observations under ultra-high dimension,where the missing observations include either responses or covariates or the responses and part of the covariates are missing at random,and the ultra-high dimension implies that the dimension of parameter is much larger than sample *** on the B-spline method for the varying coefficient functions,we study the consistency of the oracle estimator which is obtained only using active covariates whose coefficients are *** the same time,we discuss the asymptotic normality of the oracle estimator for the linear *** that the active covariates are unknown in practice,non-convex penalized estimator is investigated for simultaneous variable selection and estimation,whose oracle property is also *** sample behavior of the proposed methods is investigated via simulations and real data analysis.

关键词： Missing observation oracle property partially linear varying-coefficient model quantile regression ultra-high dimension