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mainchain conf.rmation ordering self.assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2024年

作者： Yuzhu Li Yumeng Gao f.ng Tian Yu Wang Yuan Yao Shaoliang Lin Xiang ma Binbin Xu Shanghai Key Laboratory of.Advanced Polymeric materials Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai Synchrotron Radiation f.cility Shanghai Advanced Research Institute Chinese Academy of Sciences Key Laboratory f.r Advance materials and f.ringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular Engineering East China University of Science & Technology

Developing organic room-temperature phosphorescence(RTP) materials with a wide range of.tunable-emission is signif.cant in expanding the applications of.RTP materials. Herein, we rationally designed amphiphilic alternating copolymers poly(1,2-bis(4-alkoxyphenyl)ethane-1,2-dione-alt-(ethylene glycol)x)(P(Bz-alt-EGx)) that combined the advantage of.alternating benzil and EGxskeleton, and tunable mainchain conf.rmation. Through a mainchain conf.rmation ordering assembly(COA) process, P(Bz-alt-EGx) self.assembled into well-def.ned platelets, and such assemblies emitted blue RTP at ca. 425 nm due to the ordered f.lded-chain conf.rmation and conf.ned microenvironment. in contrast, traditional self.assembly(ta) of.P(Bz-alt-EGx) obtained less ordered aggregates, such as asymmetric worms, vesicles, and rod-like micelles. The resultant less ordered aggregates exhibited yellow-green RTP at ca. 550 nm. The wide-tuning RTP emission in solution(between blue and yellow-green, over125 nm) is realized using the P(Bz-alt-EGx) alternating copolymers under the treatment of.dif.erent self.assembly *** study uncovers a new strategy to tailor the RTP emission through dif.erent self.assembly pathways and holds great promise f.r the f.brication of.advanced optical materials.

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TC4表面激光熔覆硬质复合涂层组织与性能

华南理工大学学报（自然科学版） 2024年第3期52卷 10-17页

作者：付宇明马顺芯刘绍峰郑立娟燕山大学机械工程学院河北秦皇岛066004

TC4凭借比强度高、耐腐蚀性好、质量轻等一系列优点,被广泛应用于航空航天领域,但其摩擦系数大、耐磨性差等缺点极大地限制了其应用范围,针对TC4硬度低、耐磨性差等缺点,采用4 kW大功率Laser4000半导体激光器,选用过渡族难熔碳化物Hf.、... 详细信息

TC4凭借比强度高、耐腐蚀性好、质量轻等一系列优点,被广泛应用于航空航天领域,但其摩擦系数大、耐磨性差等缺点极大地限制了其应用范围,针对TC4硬度低、耐磨性差等缺点,采用4 kW大功率Laser4000半导体激光器,选用过渡族难熔碳化物Hf.、taC和ZrC作为增强相,以H13钢基粉末作为基粉,利用激光熔覆技术在TC4表面制备了不同比例的钢基金属-陶瓷硬质涂层。之后利用扫描电镜(SEM)、EDS能谱仪、D/max-2500/PC型X射线衍射仪(XDR)等试验手段对不同比例涂层的宏观形貌、显微组织、物相组成和涂层元素分布等进行对比分析,利用Qness型号维氏显微硬度计测试涂层硬度并分析熔覆试样截面微观硬度变化规律,利用MMU-5G型端面摩擦磨损试验机研究了不同材料组分涂层的摩擦磨损性能,研究结果表明:试件熔覆层与基材形成了良好的冶金结合,熔覆层组织形态主要以枝晶组织以及块状组织为主,各熔覆层的主要物相中均含有TiC,随着三元陶瓷粉末含量的增加,MC的含量也随之增加,当碳化物混合粉末添加量为15%(质量分数)时,熔覆层中检测到Hf.(0.8)ta_(0.2)f._(2)三元合金相。当三元陶瓷粉添含量为10%(质量分数)时,熔覆层晶粒最为细小,涂层平均硬度最高,平均硬度约为763.43 HV,是基材硬度的2.29倍,当三元陶瓷粉末含量为5%(质量分数)时涂层的耐磨性最好,相对耐磨性为25%。

关键词： TC4钛合金激光熔覆金属陶瓷涂层过渡族碳化物

Cu_(2)O纳米颗粒对小麦幼苗快速叶绿素荧光诱导动力学特征及相关基因的影响

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应用生态学报 2024年第3期35卷 721-730页

作者：郭葳王楠张凯悦宋沛沛马占强河南科技大学农学院/牡丹学院河南洛阳471000

土壤中金属纳米颗粒可引发蓄积效应进而威胁农作物的生态安全。探讨氧化亚铜纳米颗粒(Cu2O-NPs)对小麦幼苗叶片光系统Ⅱ(PSⅡ)的影响,对了解Cu2O-NPs对农作物光合作用的影响具有重要意义。本研究以“周麦18”小麦为供试植物,采用水培法... 详细信息

土壤中金属纳米颗粒可引发蓄积效应进而威胁农作物的生态安全。探讨氧化亚铜纳米颗粒(Cu2O-NPs)对小麦幼苗叶片光系统Ⅱ(PSⅡ)的影响,对了解Cu2O-NPs对农作物光合作用的影响具有重要意义。本研究以“周麦18”小麦为供试植物,采用水培法,研究了0、10、50、100和200 mg·L^(-1) Cu_(2)O-NPs对小麦幼苗叶绿素荧光诱导动力学特性及相关基因的影响。结果表明:随着Cu2O-NPs浓度的增加,小麦叶片叶绿素含量降低,OJiP曲线的标准化出现明显的K相(ΔK>0),PSⅡ反应中心活性参数[单位反应中心吸收的光能(ABS/RC)、单位反应中心捕获的光能(TRo/RC)、单位反应中心捕获的用于电子传递的能量(ETo/RC)和单位反应中心以热能形式耗散的能量(Dio/RC)]的值升高,PSⅡ能量分配比率参数[PSⅡ最大光化学效率(φ_(Po))、用于电子传递的量子产额(φEo)和捕获的激子将电子传递到qa以后的其他电子受体的概率(ψo)]呈下降趋势,而用于热耗散的量子比率(φDo)升高。小麦幼苗叶片光合量子产率Y(Ⅱ)、光化学猝灭系数(qP)、净光合速率(Pn)、气孔导度(gs)、胞间CO_(2)浓度(Ci)和蒸腾速率(Tr)随Cu_(2)O-NPs处理浓度的增加而降低。Cu_(2)O-NPs胁迫下,小麦幼苗叶片PSⅡ基因(PsbD、PsbP、Lhcb1)、Rubisco大亚基基因(RbcL)、细胞色素b6/f.合体基因(PetD、Rieske)和ATP合成酶类基因(AtpA、AtpB、AtpE、Atpi)均显著下调。综上,施加Cu2O-NPs改变了小麦幼苗PSⅡ的活性及结构,PSⅡ反应中心活性、PSⅡ供体侧和受体侧性能参数等均受到影响,PSⅡ相关基因下调,并表现出明显的浓度效应。

关键词：小麦氧化亚铜纳米颗粒叶绿素荧光光合系统Ⅱ

Structure-based design of.pan-coronavirus inhibitors targeting host cathepsin L and calpain-1

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Signal Transduction and targeted Therapy 2024年第4期9卷 1651-1664页

作者： Xiong Xie Qiaoshuai Lan Jinyi Zhao Sulin Zhang Lu Liu Yumin Zhang Wei Xu maolin Shao Jingjing Peng Shuai Xia Yan Zhu Keke Zhang Xianglei Zhang Ruxue Zhang jian Li Wenhao Dai Zhen Ge Shulei Hu Changyue Yu Jiang Wang Dakota ma Mingyue Zheng Haitao Yang Gengf. Xiao Zihe Rao Lu Lu Leike Zhang f.ng Bai Yao Zhao Shibo Jiang Hong Liu Drug Discovery and Design Center State Key Laboratory of Drug ResearchCAS Key Laboratory of Receptor ResearchShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of.Chinese Academy of.Sciences Beijing 100049China Key Laboratory of.Medical Molecular Virology(MOE/NHC/CAMS) School of Basic Medical SciencesShanghai Institute of Infectious Disease and BiosecurityFudan UniversityShanghai 200032China Shanghai institute f.r Advanced immunochemical Studies and School of.Lif. Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of.Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China School of.Chinese materia Medica Nanjing University of Chinese Medicine138 Xian Lin RoadJiangsu 210023 NanjingChina School of.Pharmaceutical Science and Technology Hangzhou Institute for Advanced StudyUCASHangzhou 310024China National Clinical Research Center f.r inf.ctious Disease Shenzhen Third People's HospitalShenzhen 518112China

Respiratory disease caused by coronavirus inf.ction remains a global health *** several SARS-CoV-2-specif.c vaccines and direct-acting antivirals are available,their ef.cacy on emerging coronaviruses in the f.ture,including SARS-CoV-2 variants,might be ***-targeting antivirals provide preventive and therapeutic strategies to overcome resistance and manage f.ture outbreak of.emerging *** L(CTSL)and calpain-1(CAPN1)are host cysteine proteases which play crucial roles in coronaviral entrance into cells and inf.ction-related immune ***,two peptidomimetic a-ketoamide compounds,14a and 14b,were identif.ed as potent dual target inhibitors against CTSL and *** X-ray crystal structures of.human CTSL and CAPN1 in complex with 14a and 14b revealed the covalent binding of.a-ketoamide groups of.14a and 14b to C25 of.CTSL and C115 of.*** showed potent and broad-spectrum anticoronaviral activities in vitro,and it is worth noting that they exhibited low nanomolar potency against SARS-CoV-2 and its variants of.concern(VOCs)with ECso values ranging f.om 0.80 to 161.7 nM in various *** mechanistic exploration indicated that they exhibited anticoronaviral activity through blocking viral ***,14a and 14b exhibited good oral pharmacokinetic properties in mice,rats and dogs,and f.vorable saf.ty in *** addition,both 14a and 14b treatments demonstrated potent antiviral potency against SARS-CoV-2 XBB 1.16 variant inf.ction in a K18-hACE2 transgenic mouse *** 14b also showed ef.ective antiviral activity against HCoV-OC43 inf.ction in a mouse model with a f.nal survival rate of.60%.f.rther evaluation showed that 14a and 14b exhibited excellent antiinf.ammatory ef.ects in Raw 264.7 mouse macrophages and in mice with acute *** together,these results suggested that 14a and 14b are promising drug candidates,providing novel insight into developing pan-coronavirus inhibitors with anti

关键词： calpain overcome entrance

A common property of.R(E,f. and B(R^n,R^m) and a new method f.r seeking a path to connect two operators

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Science China mathematics 2010年第10期53卷 2605-2620页

作者： ma Zhaof.ng ma JiPu Zhejiang inst Commun Dept Informat & Management Hangzhou 311112 Zhejiang Peoples R China Harbin Normal Univ Tseng Yuan Rong Funct Anal Res Ctr Harbin 150025 Peoples R China

Given two Banach spaces E,f.let B(E,f. be the set of.all bounded linear operators f.om E into f.and R(E,f. the set of.all operators in B(E,f. with f.nite *** is well-known that B(Rn) is a Banach space as well as an algebra,while B(Rn,Rm) f.r m = n,is a Banach space but not an algebra;meanwhile,it is clear that R(E,f. is neither a Banach space nor an ***,in this paper,it is proved that all of.them have a common property in geometry and topology,i.e.,they are all a union of.mutual disjoint path-connected and smooth submanif.lds (or hypersurf.ces).Let Σr be the set of.all operators of.f.nite rank r in B(E,f. (or B(Rn,Rm)).in f.ct,we have that 1) suppose Σr∈ B(Rn,Rm),and then Σr is a smooth and path-connected submanif.ld of.B(Rn,Rm) and dimΣr = (n + m)r-r2,f.r each r ∈ [0,min{n,m});if.m = n,the same conclusion f.r Σr and its dimension is valid f.r each r ∈ [0,min{n,m}];2) suppose Σr∈ B(E,f.,and dimf.= ∞,and then Σr is a smooth and path-connected submanif.ld of.B(E,f. with the tangent space taΣr = {B ∈ B(E,f. : BN(A)-R(A)} at each A ∈Σr f.r 0 r ine methods f.r seeking a path to connect two operators can hardly apply here.A new method and some f.ndamental theorems are introduced in this paper,which is development of.elementary transf.rmation of.matrices in B(Rn),and more adapted and simple than the elementary transf.rmation *** addition to tensor analysis and application of.Thom’s f.mous result f.r transversility,these will benef.t the study of.inf.nite geometry.

关键词： operator of f.nite rank smooth Banach submanif.ld matrix

持续负荷冲击下AnSBBR运行性能及群落结构响应

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中国环境科学 2024年第1期44卷 140-149页

作者：王泽于莉芳马芷萱郑兰香刘然刘甜西安建筑科技大学环境与市政工程学院陕西西安710055 宁夏大学生态环境学院宁夏银川750021 中国葡萄酒产业技术研究院宁夏银川750021

以厌氧序批式生物膜反应器(AnSBBR)处理葡萄酒生产废水,考察反应器在持续负荷冲击下的运行特性及群落结构响应.结果显示,持续负荷冲击的前13d(29~41d),反应器运行稳定;因逐渐增加的氢分压和挥发性脂肪酸(Vf.s),到56d时系统稳定性降低(Vf...

以厌氧序批式生物膜反应器(AnSBBR)处理葡萄酒生产废水,考察反应器在持续负荷冲击下的运行特性及群落结构响应.结果显示,持续负荷冲击的前13d(29~41d),反应器运行稳定;因逐渐增加的氢分压和挥发性脂肪酸(Vf.s),到56d时系统稳定性降低(Vf./ta=0.72),乙酸比产甲烷活性(Sma)降低46.2%,但氢利用速率(HUR)增加69.2%,辅酶f.20浓度增加11.9%.在42d时仅外层的Slime-EPS浓度明显增加(34.1%);在56d时TB-EPS和LB-EPS浓度增加61.3%和62.8%,其PN/PS比值增加197.8%和126.0%,负荷冲击诱导EPS分泌大量的应急性蛋白类产物,其电活性物质提高了系统的电子传递活性(35.5%).illumina MiSeq显示,负荷冲击下Desulf.vibrio、Ruminococcus和Geobacter等产酸菌丰度降低,而Methanobacterium丰度由32.2%增至50.9%.生物膜系统通过逐级EPS分泌和强化还原CO_(2)产甲烷来响应持续负荷冲击的影响.

关键词：厌氧序批式生物膜反应器负荷冲击胞外聚合物代谢活性群落结构

鲁西地区沂南金矿床成因:硫化物矿石与围岩稀土和微量元素的制约

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地质通报 2024年第6期43卷 896-913页

作者：李亚东马明蔡文艳高继雷张照录孙祥彪山东省第一地质矿产勘查院山东济南250100 山东省富铁矿勘查技术开发工程实验室山东济南250100 山东理工大学资源与环境工程学院山东淄博255000 自然资源部战略性金属矿产找矿理论与技术重点实验室/中国地质大学(北京) 北京100083 呼伦贝尔山金矿业有限公司内蒙古呼伦贝尔022357

沂南金矿床为鲁西地区典型的矽卡岩型矿床,产于早白垩世中酸性杂岩与新太古界—寒武系接触带及其附近。本次利用岩/矿石稀土和微量元素组成,示踪成矿物质来源及成矿流体地球化学性质。结果显示,成矿的闪长玢岩负Eu异常不显著,且早矿化... 详细信息

沂南金矿床为鲁西地区典型的矽卡岩型矿床,产于早白垩世中酸性杂岩与新太古界—寒武系接触带及其附近。本次利用岩/矿石稀土和微量元素组成,示踪成矿物质来源及成矿流体地球化学性质。结果显示,成矿的闪长玢岩负Eu异常不显著,且早矿化阶段发育大量磁铁矿,暗示早阶段成矿流体具有氧化性特征。晚(金)矿化阶段的黄铁矿和黄铜矿相对富集轻稀土元素和高场强元素,负Eu异常显著,Ce异常不明显,且Hf.Sm、Nb/La值大于1,显示含f.的还原性流体特征。矿石的Y/Ho、Zr/Hf.Nb/ta值变化较大,且黄铁矿Co/Ni>10,表明成矿流体源于岩浆水和大气降水的混入。矿石与赋矿围岩具有相似的稀土元素配分模式和微量元素地球化学行为,且具有相同范围/趋势的微量元素比值,说明沂南杂岩体和碳酸盐岩提供了必要的成矿物质。综上,沂南金矿床的成矿过程得到了较好的约束,同时也对区域范围内金矿成因有一定指示意义。

关键词：黄铁矿和黄铜矿稀土和微量元素成矿流体成矿物质来源沂南金矿鲁西地区

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Ef.ects of.light intensity on photosynthesis and photoprotective mechanisms in apple under progressive drought

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Journal of.integrative Agriculture 2015年第9期14卷 1755-1766页

作者： ma Ping BAi Tuan-hui WANG Xiao-qian ma f.ng-wang College of.Horticulture Northwest A&F UniversityState Key Laboratory of Crop Stress Biology for Arid Areas

The ef.ects of.light intensity on photosynthesis and photoprotective mechanisms under progressive drought were studied on apple trees (malus domestica Borkh.) f.ji. The potted trees were exposed to drought stress f.r 12 days and dif.erent light conditions (100, 60 and 25%sunlight). During the progressive drought, the relative water content (RWC) in leaf.declined and was f.ster in f.l light than in 60 and 25%sunlight. However, the decrease in the net photosynthetic rate (Pn), stomatal conductance (Gs) and Rubisco activity were slower under 100%sunlight condition than other light conditions. Af.er the 6 days of.drought, the maximum PSii quantum yield (f./f.), the capacity of.electrons move beyond qa?(1–VJ) and electron move f.om intersystem to PSi acceptor side (1–Vi)/(1–VJ) decreased, with greater decline extent in brighter light. While RWCs were>75%, the variations in dif.erent light intensities of.Gs and Rubisco activity at identical RWC, suggested the direct ef.ects of.light. While the little dif.erence in the state of.photosynthetic electron transport chain among tested light intensities indicates the results of.f.ster water loss rate of.light. Our results also demonstrated that the enhancement the de-epoxidations of.xanthophyl cycle, activities of.ascorbate peroxidase (APX) and catalase (CAT) were directly regulated by light intensity. While the higher photorespiration rate (Pr) under stronger light condition was mainly caused by f.ster water loss rate of.light.

关键词： appl e drought stress photosynthesis photoprotection

Perf.rmance and calibration of.quark/gluon-jet taggers using 140 f.^(-1) of.pp collisions at √s=13 TeV with the ATLAS detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： G. Aad B. Abbott K. Abeling N.J. Abicht S.H. Abidi A. Aboulhorma H. Abramowicz H. Abreu Y. Abulaiti B.S. Acharya C. Adam Bourdarios L. Adamczyk S.V. Addepalli M.J. Addison J. Adelman A. Adiguzel T. Adye A.A. Af.older Y. Af.k M.N. Agaras J. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad f. Ahmadov W.S. Ahmed S. Ahuja X. Ai G. Aielli A. Aikot M. Ait tamlihat B. Aitbenchikh i. Aizenberg M. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama N.N. Akolkar K. Al Khoury G.L. Alberghi J. Albert P. Albicocco G.L. Albouy S. Alderweireldt M. Aleksa i.N. Aleksandrov C. Alexa T. Alexopoulos f. Alf.nsi M. Algren M. Alhroob B. Ali H.M.J. Ali S. Ali S.W. Alibocus M. Aliev G. Alimonti W. Alkakhi C. Allaire B.M.M. Allbrooke J.f. Allen C.A. Allendes f.ores P.P. Allport A. Aloisio f. Alonso C. Alpigiani M. Alvarez Estevez A. Alvarez f.rnandez M. Alves Cardoso M.G. Alviggi M. Aly Y. Amaral Coutinho A. Ambler C. Amelung M. Amerl C.G. Ames D. Amidei S.P. Amor Dos Santos K.R. Amos V. Ananiev C. Anastopoulos T. Andeen J.K. Anders S.Y. Andrean A. Andreazza S. Angelidakis A. Angerami A.V. Anisenkov A. Annovi C. Antel M.T. Anthony E. Antipov M. Antonelli f. Anulli M. Aoki T. Aoki J.A. Aparisi Pozo M.A. Aparo L. Aperio Bella C. Appelt A. Apyan N. Aranzabal S.J. Arbiol Val C. Arcangeletti A.T.H. Arce E. Arena J-f. Arguin S. Argyropoulos J.-H. Arling O. Arnaez H. Arnold G. Artoni H. Asada K. Asai S. Asai N.A. Asbah J. Assahsah K. Assamagan R. Astalos S. Atashi R.J. Atkin M. Atkinson H. Atmani P.A. Atmasiddha K. Augsten S. Auricchio A.D. Auriol V.A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu f. Backman A. Badea P. Bagnaia M. Bahmani A.J. Bailey V.R. Bailey J.T. Baines L. Baines O.K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan R. Balasubramanian E.M. Baldin P. Balek E. Ballabene f. Balli L.M. Baltes W.K. Balunas J. Balz E. Banas M. Bandieramonte A. Bandyopadhyay S. Bansal L. Barak M. Barakat E.L. Barberio D. Barberis M. Barbero M.Z. Barel K.N. Barends T. Barillari M-S. Barisits T. Barklow P. Baron D.A. Baron Mo The ATLAS Collaboration

The identif.cation of.jets originating f.om quarks and gluons,of.en ref.rred to as quark/gluon tagging,plays an important role in various analyses perf.rmed at the Large Hadron Collider,as Standard Model measurements and searches f.r new particles decaying to quarks of.en rely on suppressing a large gluon-induced *** paper describes the measurement of.the ef.iciencies of.quark/gluon taggers developed within the ATLAS Collaboration,using √s=13 TeV proton–proton collision data with an integrated luminosity of.140 f.^(-1) collected by the ATLAS *** taggers with high perf.rmances in rejecting jets f.om gluon over jets f.om quarks are studied:one tagger is based on requirements on the number of.inner-detector tracks associated with the jet,and the other combines several jet substructure observables using a boosted decision tree.A method is established to determine the quark/gluon f.action in data,by using quark/gluon-enriched subsamples def.ned by the jet *** in tagging ef.iciency between data and simulation are provided f.r jets with transverse momentum between 500 GeV and 2 TeV and f.r multiple tagger working points.

关键词： ATLAS JET QUARK GLUON taGGiNG