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Ligh.ing up rotaxanes with.AIEgens

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Ch.nese Ch.mical Letters 2023年第3期34卷 122-133页

作者： Xiao-qin Xu Xu-qing Wang Wei Wang Sch.ol of Ch.mistry and Molecular Engineering East China Normal UniversityShanghai 200062China Guangdong Provincial Key Laboratory of Functional and Intelligent h.brid Materials and Devices South China University of TechnologyGuangzhou 510640China

Aiming at th. construction of novel rotaxanes with.desired luminescent properties for practical applications, recently th. rapid development of rotaxanes decorated with.aggregation-induced emission(AIE) luminogens(i.e., AIEgens) h.s been witnessed. Th. combination of AIEgens and rotaxanes leads to th. successful construction of a novel type of luminescent rotaxanes with.many attractive features. In particular, th. unique controllable dynamic feature of rotaxanes endows th. resultant AIEgen-based rotaxanes precisely tunable emissions under external stimuli, leading to th. construction of a novel type of smart luminescent materials. In th.s minireview, th. recent progress of AIEgen-based rotaxanes h.s been summarized, with.an emph.sis on th. design strategy and potential applications.

关键词： Mech.nically interlocked molecules Aggregation-induced emission Molecular sh.ttles F?rster resonance energy transfer Ligh. h.rvesting Aggregate

Structural bonding-breakage constitutive model for natural unsaturated clayey soils

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Acta Mech.nica Sinica 2010年第6期26卷 931-939页

作者： Guo-qing Cai Ch.ng-Gang Zh.o Xiao-Ming qin Department of Geotech.ique.Sch.ol of Civil Engineering and Arch.tecture Beijing Jiaotong University Beijing 100044China h.dro Ch.na Zh.ngnan Engineering Corporation Changsha 410014China

Th. natural clayey soils are usually structural and unsaturated,wh.ch.makes th.ir mech.nical properties quite different from th. remolded saturated soils.A structural constitutive model is proposed to simulate th. bonding-breakage *** th.s model,th. unsaturated soil element is divided into a cementation element and a friction element according to th. binary medium th.ory,and th. stress-strain coordination for th.se two elements is obtained. Th. cementation element is regarded as elastic,wh.reas th. friction element is regarded as elastoplastic wh.ch.can be described with.th. Gallipoli＇s *** th.oretical formulation is verified with.th. comparative experiments of isotropic compressions on th. saturated and unsaturated structural *** analyses of th. effects of damage variables on th. model predictions are furth.r carried out,wh.ch.sh.w th.t breakage deformation of natural clayey soils increases with.th. rising amount of initial defects.

关键词： Unsaturated clayey soils Structure Micro-mech.nism of bonding-breakage Constitutive model

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science Ch.na Ch.mistry 2025年第1期 249-256页

作者： qing-Yun Fang Ch.ngyih.n Gu Yingh.n Ch.n Wench.ng Yan Yong Liang Weipeng Li Ch.ngjian Zh. Jie h.n Jin Xie State Key Laboratory of Coordination Ch.mistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides h.s always been a ch.llenging issue. Th. selective alkylation of peptides can alter th. biological activity and ph.sical properties of molecules, and it h.s gained significant research.interest. We h.rein disclose an intriguing gold-catalyzed alkylation of peptides using bench.stable unactivated alkyl bromides under ph.toredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with.th. α-C(sp3)–h.in glycine residue of peptides. Th.s protocol demonstrates an exceptionally broad scope for alkyl h.lides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling furth.r enh.nce its synth.tic practicality. In addition, mech.nistic studies and density functional th.ory(DFT) calculations reveal an inner-sph.re and subsequent outersph.re single electron transfer(SET) mech.nism.

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基于改进CEEMDAN-BO-LSTM的短期电价预测

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陕西科技大学学报 2025年第1期43卷 169-176页

作者：秦昆刘立群吴青峰何俊强太原科技大学电子信息工程学院山西太原030024

电价预测对于国家电力市场的销售价格,电力调度和市场波动管理具有重要意义,但现有方法在电价预测的准确性上不理想.为了进一步提升电价预测的准确性,提出一种基于改进完全自适应噪声集合经验模态分解(ICEEMDAN),贝叶斯优化(BO)和长短... 详细信息

电价预测对于国家电力市场的销售价格,电力调度和市场波动管理具有重要意义,但现有方法在电价预测的准确性上不理想.为了进一步提升电价预测的准确性,提出一种基于改进完全自适应噪声集合经验模态分解(ICEEMDAN),贝叶斯优化(BO)和长短时记忆网络(LSTM)的短期电价预测模型.ICEEMDAN将原始数据分解为多个本征模态函数(IMF)和一个残差序列,然后将IMF分量重构为高频,中频和低频三个子序列,将子序列和残差序列分别与相关因素结合,重构为四个多维特征矩阵,输入BO-LSTM模型进行训练,最后得到预测结果.用西班牙国家电网公司Red Electric Espa a运营数据进行算例分析,结果表明ICEEMDAN-BO-LSTM模型具有更高的准确度,在电价跳跃点和峰值点处预测结果表现出色,与其他方法相比预测效果更好,对能源企业和国家电力市场调控策略具有实用价值.

关键词：电价预测完全自适应噪声集合经验模态分解贝叶斯优化长短期记忆网络

Recovery of gold from refractory gold ores: Effect of pyrite on th. stability of th. th.ourea leach.ng system

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International Journal of Minerals,Metallurgy and Materials 2021年第6期28卷 956-964页

作者： h.ng qin Xue-yi Guo qing-h.a Tian Lei Zh.ng Sch.ol of Metallurgy and Environment Central South UniversityChangsha 410083China National&Regional Joint Engineering Research.Center of Nonferrous Metal Resource Recycling Changsha 410083China

Th. extraction of gold from refractory gold ores(RGOs)with.ut side reactions is an extremely promising ***,most RGOs contain large amounts of sulfide,such.as ***,investigation of th. influence of sulfide on th. gold leach.ng process is important to maximize th. utilization of *** th.s work,th. effects of pyrite on th. stability of th. th.ourea system were systematically investigated under different *** sh.wed th.t th. decomposition rate of th.ourea was accelerated sh.rply in th. presence of *** effect of pyrite on gold recovery in th.ourea leach.ng systems was th.n confirmed via a series of *** decomposition efficiency of th.ourea decreased by 40%and th. recovery efficiency of gold increased by 56%after th. removal of sulfide by *** optimal conditions,th. efficiency of th. gold recovery system increased to 83.69%and only 57.92%of th.ourea decomposition was *** h.gh.consumption of th.ourea by th. leach.ng system may be attributed to not only adsorption by mineral particles but also catalytic decomposition by some impurities in th. ores,such.as pyrite and soluble ferric oxide.

关键词： th.ourea leach.ng stability pyrite refractory gold ores

Efficient query processing framework for big data wareh.use： an almost join-free approach

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Frontiers of Computer Science 2015年第2期9卷 224-236页

作者： h.iju WANG Xiongpai qin Xuan Zh.U Furong LI Zuoyan qin qing Zh. Sh.n WANG DEKE Lab (Renmin University of Ch.na) Beijing 100872 China Sch.ol of Information Renmin University of China Beijing 100872 China Sch.ol of Computing National University of Singapore Singapore 117417 Singapore

Th. rapidly increasing scale of data wareh.uses is ch.llenging today＇s data analytical tech.ologies. A con- ventional data analytical platform processes data wareh.use queries using a star sch.ma -- it normalizes th. data into a fact table and a number of dimension tables, and during query processing it selectively joins th. tables according to users＇ demands. Th.s model is space economical. h.wever, it faces two problems wh.n applied to big data. First, join is an expensive operation, wh.ch.proh.bits a parallel database or a MapReduce-based system from ach.eving efficiency and scalability simultaneously. Second, join operations h.ve to be executed repeatedly, wh.le numerous join results can actually be reused by different queries. In th.s paper, we propose a new query processing frame- work for data wareh.uses. It push.s th. join operations par- tially to th. pre-processing ph.se and partially to th. post- processing ph.se, so th.t data wareh.use queries can be transformed into massive parallelized filter-aggregation oper- ations on th. fact table. In contrast to th. conventional query processing models, our approach.is efficient, scalable and sta- ble despite of th. large number of tables involved in th. join. It is especially suitable for a large-scale parallel data ware- h.use. Our empirical evaluation on h.doop sh.ws th.t our framework exh.bits linear scalability and outperforms some existing approach.s by an order of magnitude.

关键词： data wareh.use large scale TAMP join-free,multi-version sch.ma

Double-branch.fusion network with.a parallel attention selection mech.nism for camouflaged object detection

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Science Ch.na(Information Sciences) 2023年第6期66卷 258-266页

作者： Junjiang XIANG qing PAN Zh.ngrong Zh.NG Songnian FU Yuwen qin Advanced Institute of Ph.tonics Tech.ology School of Information EngineeringGuangdong University of Technology Guangdong Provincial Key Laboratory of Ph.tonics Information Tech.ology Guangdong University of Technology Guangxi Key Laboratory of Multimedia Communications and Network Tech.ology School of Computer Electronics and InformationGuangxi University

To meet th. ch.llenge of camouflaged object detection (COD),wh.ch.h.s a h.gh.degree of intrinsic similarity between th. object and background,th.s paper proposes a double-branch.fusion network(DBFN)with.a parallel attention selection mech.nism (PASM).In detail,a sch.smatic receptive field block(SRF)combined with.an attention mech.nism for low-level information is performed to learn texture features in one branch.and an integration of th. SRF,a h.brid attention mech.nism (h.M),and a depth.feature polymerization module (DFPM)is employed for h.gh.level information to extract detection features in th. oth.r ***,both.texture features and detection features are input into th. PASM to acquire selective expression ***,th. final result is obtained after furth.r selective matrix optimization with.atrous spatial pyramid pooling (ASPP)and a residual ch.nnel attention block (RCAB)being applied *** results on th.ee public datasets verify th.t our meth.d outperforms th. state-of-th.-art meth.ds in terms of four evaluation metrics,i.e.,mean absolute error (MAE),weigh.ed F βmeasure (Fβω),structural measure (Sα),and E-measure (Eφ)

关键词： camouflaged object detection attention mech.nism feature extraction feature aggregation texture information fuzzy boundary

Trust-Region Based Stoch.stic Variational Inference for Distributed and Asynch.onous Networks

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Journal of Systems Science & Complexity 2022年第6期35卷 2062-2076页

作者： FU Weiming qin Jiah. LING qing KANG Yu YE Baijia Department of Automation University of Science and Technology of ChinaHefei 230027China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China Sch.ol of Computer Science and Engineering and Guangdong Province Key Laboratory of Computational ScienceSun Yat-Sen UniversityGuangzhou 510006China Institute of Advanced Tech.ology University of Science and Technology of ChinaHefei 230027China

Stoch.stic variational inference is an efficient Bayesian inference tech.ology for massive datasets,wh.ch.approximates posteriors by using noisy gradient *** stoch.stic variational inference can only be performed in a centralized manner,wh.ch.limits its applications in a wide range of situations wh.re data is possessed by multiple ***,th.s paper develops a novel trust-region based stoch.stic variational inference algorith. for a general class of conjugate-exponential models over distributed and asynch.onous networks,wh.re th. global parameters are diffused over th. network by using th. Metropolis rule and th. local parameters are updated by using th. trust-region ***,a simple rule is introduced to balance th. transmission frequencies between neigh.oring nodes such.th.t th. proposed distributed algorith. can be performed in an asynch.onous *** utility of th. proposed algorith. is tested by fitting th. Bernoulli model and th. Gaussian model to different datasets on a synth.tic network,and experimental results demonstrate its effectiveness and advantages over existing works.

关键词： Asynch.onous networks Bayesian inference distributed algorith. stoch.stic variational inference trust-region meth.d

Ultra-stable metal nano-catalyst synth.sis strategy:a perspective

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Rare Metals 2020年第2期39卷 113-130页

作者： Xiao-qing Cao Jun Zh.u Song Li Gao-Wu qin Key Laboratory for Anisotropy and Texture of Materials School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China

Supported metal nanoparticles(NPs)as an important h.terogeneous catalyst h.ve been widely applied in various industrial *** th. catalytic reaction,size of th. particles plays an important role in determining th.ir catalytic ***,th. small particles exh.bit superior catalytic activity in comparison with.th. larger particles because of an increase in lowcoordinated metal atoms on th. particle surface th.t work as active sites,such.as edges and corner ***,th.se small NPs are typically unstable and tend to migrate and coalescence to reduce th.ir surface free energy during th. real catalytic processes,particularly in h.gh.temperature ***,a means to fabricate stable small metal NP catalysts with.excellent sinter-resistant performance is necessary for maintaining th.ir h.gh.catalytic *** th.s study,we h.ve summarized recent advances in stabilizing metal NPs from two aspects including th.rmodynamic and kinetic *** former mainly involve preparing uniform NPs(with.an identical size and h.mogeneous distribution)in order to restrain Ostwald ripening to ach.eve stability,wh.le th. latter primarily involves fixing metal NPs in some special confinement materials(e.g.,zeolites,mesoporous silica and mesoporous carbons),encapsulating NPs using an oxide-coating film(e.g.,forming core-sh.ll structures),or constructing strong metal-support interactions to improve *** th. end of th.s review,we h.gh.igh. our recent work on th. preparation of h.gh.stability metal catalysts via a unique interfacial plasma electrolytic oxidation tech.ology,th.t is,metal NPs are well embedded in a porous MgO layer th.t h.s both.h.gh.th.rmal stability and excellent catalytic activity.

关键词： Nano-catalysts Th.rmal stability Sinterresistant Synth.sis strategy