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Science China Chemistry 2025年第01期 257-263页

作者： Jiapian Huang Chenxin Wang Xu Wang Xiaoyu Zhou Wei Xiao Jie wu School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

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Mathematical model of deoxidization with post stirring in a combined blowing converter

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 541-545页

作者： Jie Feng Yan-ping Bao Xun wu heng Cui Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering Heibei University of Science and Technology Shijiazhuang 050035 China

Dissolved oxygen in the steel at the terminal of the converter smelting process is the main cause for the formation of oxide inclusions, and the high terminal oxygen content worsens the steel cleanness. However, post stirring in a combined blowing converter can promote the carbon-oxygen reaction in the liquid steel and reduce the dissolved oxygen content at the terminal of the converter smelting process. Thus, the mathematical model of deoxidization in the post stirring process was obtained, and the rationality of which was further verified by industrial tests. Finally, it is concluded that the product of dissolved carbon and oxygen, i.e. w[C]·w[O], decreases obviously after adopting the new technique of post stirring in the combined blowing converter.

关键词： steelmaking converter deoxidization mathematical model

Observing spectral characteristics over a continental shelf and slope in the South China Sea

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Acta Oceanologica Sinica 2013年第7期32卷 29-37页

作者： shang Xiaodong XU Chi CHEN Guiying wu Lixin State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of Sciences Institute of Acoustics Chinese Academy of Sciences

Using in situ measurement data from May-June, 1998, and data from the Asian seas international acoustics experiment （ASIAEX） from 2001 in the South China Sea （SCS）, the spectral density function and the dissipa- tion spectrum function are estimated. In the inffa-gravity wave （IGW） band, the power spectra of velocity （u, v, w） are universal functions with respect to characteristic frequencies, which correspond to the peak fre- quencies of the dissipation spectrum （PFDS）. This suggests that high-frequency internal waves in the IGW band have similar dynamical characteristics. In addition, the evolution of these characteristic frequencies is explored and its highest value is 8.8 cph （cycles per hour, 1 cph=2.778× 10-3 Hz）.

关键词： dissipation spectra,characteristic frequencies South China Sea

Effect of cerium on wettability of mechanically milled Cu-based brazing alloy powder

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Journal of Rare Earths 2018年第11期36卷 1226-1233页

作者： Qiaoping wu Zhou Luo Yu Wang heng Zhao Weijia Zheng Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-cut Material Hunan University of Science and Technology

CuSn powders and Till2 powders were milled using high energy mechanical milling to prepare Cu-based alloy powders for brazing diamond. And Ce was added to the milled Cu-based alloy powders to improve the wettability. It is found that the wetting angle reaches the minimum value 13.2° and the maximum spreading area 178 mm2 is achieved when the amount of Ce is 0.75 wt%. And Ce remarkably reduces the surface tension of liquid alloy, which improves the climbing height along the diamond and forms a massive support profile. And the results show that Ce can effectively improve the transverse rupture strength （TRS） due to high wettability. The wear characteristics of the diamonds brazed with Cu-based alloy containing 0.75 wt% Ce mainly consist of integrity, micro-fracture, fracture and rubdown, diamonds pull-out can not easily happen.

关键词： Cu-based alloy powder Ce Wettability Spreading area Climbing height Wear characteristics

Admissibility of Linear Estimators with Respect to Inequality Constraints Under Some Loss Functions

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 1073-1082页

作者： shang-li ZHANG Hong QIN Chang-chun wu School of Science Beijing Jiaotong University Faculty of Mathematics and Statistics Central China Normal University School of Mathematics and Information Jiaxing University

In this paper, we study the issue of admissibility of linear estimated functions of parameters in the multivariate linear model with respect to inequality constraints under a matrix loss and a matrix balanced loss. Under the matrix loss, when the model is not constrained, the results in the class of non-homogeneous linear estimators [Xie, 1989, Chinese Sci. Bull., 1148-1149; Xie, 1993, J. Multivariate Anal., 1071-1074] showed that the admissibility under the matrix loss and the trace loss is equivalent. However, when the model is constrained by the inequality constraints, we find this equivalency is not tenable, our result shows that the admissibility of linear estimator does not depend on the constraints again under this matrix loss, but it is contrary under the trace loss [wu, 2008, Linear Algebra Appl., 2040-2048], and it is also relative to the constraints under another matrix loss [He, 2009, Linear Algebra Appl., 241-250]. Under the matrix balanced loss, the necessary and sufficient conditions that the linear estimators are admissible in the class of homogeneous and non-homogeneous linear estimators are obtained, respectively. These results will support the theory of admissibility on the linear model with inequality constraints.

关键词： growth curve model linear estimation admissibility incomplete ellipsoidal restriction

Smart Gas Sensors: Recent Developments and Future Prospective

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NANO-MICRO LETTERS 2025年第1期17卷 1-32页

作者： Zong, Boyang wu, Shufang Yang, Yuehong Li, Qiuju Tao, Tian Mao, Shun Tongji Univ Biomed Multidisciplinary Innovat Res Inst Coll Environm Sci & Engn Shanghai East HospState Key Lab Pollut Control & 1239 Siping Rd Shanghai 200092 Peoples R China shanghai Inst Pollut Control & Ecol Secur Shanghai 200092 Peoples R China Southern Med Univ Zhujiang Hosp Microbiome Med Ctr Dept Lab Med Guangzhou 510280 Peoples R China

Recent developments of advanced electronic and optoelectronic gas sensors are *** array with artificial intelligence algorithms and smart gas sensors in "Internet of Things" paradigm are *** of smart gas sensors in environmental monitoring, medical and healthcare applications, food quality control, and public safety are described. Gas sensor is an indispensable part of modern society with wide applications in environmental monitoring, healthcare, food industry, public safety, etc. With the development of sensor technology, wireless communication, smart monitoring terminal, cloud storage/computing technology, and artificial intelligence, smart gas sensors represent the future of gas sensing due to their merits of real-time multifunctional monitoring, early warning function, and intelligent and automated feature. Various electronic and optoelectronic gas sensors have been developed for high-performance smart gas analysis. With the development of smart terminals and the maturity of integrated technology, flexible and wearable gas sensors play an increasing role in gas analysis. This review highlights recent advances of smart gas sensors in diverse applications. The structural components and fundamental principles of electronic and optoelectronic gas sensors are described, and flexible and wearable gas sensor devices are highlighted. Moreover, sensor array with artificial intelligence algorithms and smart gas sensors in "Internet of Things" paradigm are introduced. Finally, the challenges and perspectives of smart gas sensors are discussed regarding the future need of gas sensors for smart city and healthy living.

关键词： Smart gas sensor Electronic sensor Optoelectronic sensor Flexible and wearable sensor Artificial intelligence

A benefit-aware on-demand provisioning approach for multi-tier applications in cloud computing

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Frontiers of Computer Science 2013年第4期7卷 459-474页

作者： heng wu Wenbo ZHANG Jianhua ZHANG Jun WEI Tao HUANG Institute of Software Chinese Academy of Sciences Beijing 100190 China State Key Laboratory Computer Science Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Dynamic resource provisioning is a challenging technique to meet the service level agreement （SLA） requirements of multi-tier applications in virtualization-based cloud computing. Prior efforts have addressed this challenge based on either a cost-oblivious approach or a cost-aware approach. However, both approaches may suffer frequent SLA violations under flash crowd conditions. Because they ignore the benefit gained that a multi-tier application continuously guarantees the SLA in the new configuration. In this paper, we propose a benefit-aware approach with feedback control theory to solve this problem. Experimental results based on live workload traces show that our approach can reduce resource provisioning cost by as much as 30% compared with a costoblivious approach, and can effectively reduce SLA viola- tions compared with a cost-aware approach.

关键词： cloud computing visualization resource recon-figuration feedback control benefit-aware

Stabilization of Asymmetric Underactuated Ships With Full-State Constraints: From Underactuated to Nonholonomic Configuration

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IEEE/CAA Journal of Automatica Sinica 2022年第12期9卷 2197-2199页

作者： Zhongcai Zhang Linran Tian heng Su Yuqiang wu School of Engineering Qufu Normal UniversityRizhao 276826China

Dear Editor,This letter addresses the stabilization control of an asymmetric underactuated surface ship with full-state constraints. To simplify the design of controller, the original ship model is transformed into a nonlinear cascade system with a minimum phase. Then, the stabilization of the cascade system is further processed into an equivalent stabilization of a reduced-order nonholonomic-like system. A discontinuous stabilization control method is proposed through a combination of state-scaling and state-dependent function transformations, nonlinear filters, and switching technologies. Stability analysis demonstrates that under the newly designed stabilization controller, the closed-loop system states are bounded and the desired state constraints are not violated.

关键词： stabilization system nonlinear

Global Well-posedness of the Stochastic Generalized Kuramoto-Sivashinsky Equation with Multiplicative Noise

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Acta Mathematicae Applicatae Sinica 2018年第3期34卷 566-584页

作者： Wei wu shang-bin CUI Jin-qiao DUAN Science and Information College Qingdao Agricultural University Qingdao 266109 China Department of Mathematics Sun Yat-Sen University Guangzhou 510275 China Department of Applied Mathematics Illinois Institute of Technology Chicago IL 60616 USA Center for Mathematical Sciences Huazhong University of Science and Technology Wuhan 430074 China

Global well-posedness of the initial-boundary value problem for the stochastic generalized KuramotoSivashinsky equation in a bounded domain D with a multiplicative noise is studied. It is shown that under suitable sufficient conditions, for any initial data u0 ∈L2（D×Ω）, this problem has a unique global solution u in the space L2（Ω, C（[0, T ], L2（D））） for any T 〉 0, and the solution map u0 →u is Lipschitz continuous.

关键词： Kuramoto-Sivashinsky equation stochastic partial differential equations multiplicative noise well-posedness

Genetic variation and selection of 10-year-old Eucalyptus camaldulensis based on wind damage index and wood properties

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Journal of Forestry Research 2024年第6期35卷 173-184页

作者： Xiuhua shang Zhihua wu Xiaoming Li Youshuang Wang Peijian Zhang Research Institute of Fast-Growing Trees Chinese Academy of ForestryZhanjiang 524022People’s Republic of China

Typhoons are becoming frequent and intense with ongoing climate change,threatening ecological security and healthy forest development in coastal *** of a predominant introduced species in southern China,faces significant growth challenges because of ***,it is vital to investigate the variation of related traits and select superior breeding materials for genetic ***,genetic parameter,and correlation analyses were carried out on wind damage indices and eight wood proper-ties in 88 families from 11 provenances of 10-year-old Euca-lyptus *** selection index equation was used for evaluating multiple traits and selecting superior prov-enances and family lines as future breeding *** results show that all traits were highly significantly differ-ent at provenance and family levels,with the wind damage index having the highest coefficient of genetic *** heritability of each trait ranged from 0.48 to 0.87,with the wind damage index,lignin and hemicellulose contents,and microfibril angle having the highest *** wind damage index had a positive genetic correlation with wood density,a negative correlation with lignin content,a negative phenotypic correlation and a negative genetic correlation with microfibril *** damage index and genetic progress in the selection of eight wood traits varied from 7.2%to 614.8%.Three provenances and 12 superior families were *** genetic gains of the wind damage index were 10.2%and 33.9%for provenances and families,and these may be starting material for genetic modification for wind resistance in eucalyptus and for their dissemination to typhoon-prone coastal areas of southern China.

关键词： Eucalyptus camaldulensis Wind damage index Wood properties Genetic variation Comprehensive selection