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Science China Chemistry 2024年第2期67卷 568-575页

作者： Jiasheng Qian li-Cai liu Zhi-Hao Chen Yuan liu yin li Qingjiang li Honggen Wang Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-Sen UniversityGuangzhou510006China

α-Functionalized organoborons are useful building blocks and key structural elements in functional *** previous synthesis relied on the famous matteson reaction or the late-stage borylative modification of alkynes or ***,the synthetic transformation of borylated building blocks offers another useful strategy and is currently actively *** report herein that B(MIDA)-propargylic alcohols(BPAs) are a useful type of borylated building *** two complementary functional group handles(alkyne and hydroxyl) in close proximity,the redox-neutral [3,3] and [2,3] sigmatropic rearrangements of BPAs allow the efficient synthesis of several types of α-functionalized boronates,including α,β-unsaturated acylborons,α-S/P-substituted allenylborons,boryl-substituted thiazoles and a borylated α,β-unsaturated hydrazine,some of which are otherwise challenging targets using other synthetic methods.

关键词： organoboron diverse synthesis sigmatropic rearrangement heteroarene amide

Numerical modeling and experimental investigation of a two-phase sink vortex and its fluid-solid vibration characteristics

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 47-62页

作者： Zichao yin Yesha NI lin li Tong WANG Jiafeng WU Zhe li Dapeng TAN College of Mechanical Engineering Zhejiang University of TechnologyHangzhou310014China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China

A sink vortex is a common physical phenomenon in continuous casting,chemical extraction,water conservancy,and other industrial processes,and often causes damage and loss in ***,the real-time monitoring of the sink vortex state is important for improving industrial production ***,its suction-extraction phenomenon and shock vibration characteristics in the course of its formation are complex mechanical dynamic factors for flow field state *** address this issue,we set up a multi-physics model using the level set method(LSM)for a free sink vortex to study the two-phase interaction ***,a fluid–solid coupling dynamic model was deduced to investigate the shock vibration characteristics and reveal the transition mechanism of the critical flow *** numerical results show that the coupling energy shock induces a pressure oscillation phenomenon,which appears to be a transient enhancement of vibration at the vortex penetration *** central part of the transient enhancement signal is a high-frequency *** on the dynamic coupling model,an experimental observation platform was established to verify the accuracy of the numerical *** water-model experiment results were accordant with the numerical *** above results provide a reference for fluid state recognition and active vortex control for industrial monitoring systems,such as those in aerospace pipe transport,hydropower generation,and microfluidic devices.

关键词： Free sink vortex Fluid-solid coupling Level set method(LSM) Multi-physics model Vibration characteristics

Engineering Rubisco to enhance CO_(2) utilization

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Synthetic and Systems Biotechnology 2024年第1期9卷 55-68页

作者： Lei Zhao Zhen Cai yin li Yanping Zhang CAS Key Laboratory of Microbial Physiological and Metabolic Engineering State Key Laboratory of Microbial ResourcesInstitute of MicrobiologyChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China Seeds Research Syngenta Biotechnology ChinaZhong Guan Cun Life Science ParkBeijingChina

Ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)is a pivotal enzyme that mediates the fixation of CO_(2).As the most abundant protein on earth,Rubisco has a significant impact on global carbon,water,and nitrogen ***,the significantly low carboxylation activity and competing oxygenase activity of Rubisco greatly impede high carbon fixation *** review first summarizes the current efforts in directly or indirectly modifying plant Rubisco,which has been challenging due to its high conservation and limitations in chloroplast transformation ***,recent advancements in understanding Rubisco biogenesis with the assistance of chaperones have enabled successful heterologous expression of all Rubisco forms,including plant Rubisco,in *** breakthrough facilitates the acquisition and evaluation of modified proteins,streamlining the measurement of their ***,the establishment of a screening system in *** opens up possibilities for obtaining high-performance mutant enzymes through directed ***,this review emphasizes the utilization of Rubisco in microorganisms,not only expanding their carbon-fixing capabilities but also holding significant potential for enhancing biotransformation processes.

关键词： Rubisco Plant CO_(2)fixation Microbial Carbon fixation pathway Synthetic biology Enzyme engineering

Trustworthy semi-supervised anomaly detection for online‐tooffline logistics business in merchant identification

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 544-556页

作者： Yong li Shuhang Wang Shijie Xu Jiao yin Business School China University of Political Science and LawBeijingChina JD Logistics BeijingChina Southeast University NanjingChina Institute for Sustainable Industries and liveable Cities Victoria UniversityMelbourneVictoriaAustralia

The rise of online-to-offline(O2O)e-commerce business has brought tremendous opportunities to the logistics *** the online-to-offline logistics business,it is essential to detect anomaly merchants with fraudulent shipping behaviours,such as sending other merchants'packages for profit with their low *** can help reduce the financial losses of platforms and ensure a healthy *** anomaly detection studies have mainly focused on online fraud behaviour detection,such as fraudulent purchase and comment behaviours in ***,these methods are not suitable for anomaly merchant detection in logistics due to the more complex online and offline operation of package-sending behaviours and the interpretable requirements of offline deployment in ***,a semi-supervised multiview fusion-based Anomaly Detection framework in online-to-offline logistics is proposed,which consists of a basic version SemiDet and an attention-enhanced multi-view fusion *** SemiDet,pair-wise data augmentation is first conducted to promote model robustness and address the challenge of limited labelled anomaly ***,SemiDet calculates the anomaly scoring of each merchant with an auto-encoder *** the multi-relationships among logistics merchants,a multi-view attention fusion-based anomaly detection network is further designed to capture merchants'mutual influences and improve the anomaly merchant detection performance.A post-hoc perturbation-based interpretation model is designed to output the importance of different views and ensure the trustworthiness of end-to-end anomaly *** framework based on an eight-month real-world dataset collected from one of the largest logistics platforms in China is evaluated,involving 6128 merchants and 16 million historical order consignor records in *** results show that the proposed model outperforms other baselines in both AUC-ROC and AUC-PR metrics.

关键词： artificial intelligence techniques data fusion deep learning

Ultra reliability and massive connectivity provision in integrated internet of military things(IoMT)based on tactical datalink

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Defence Technology（防务技术） 2024年第3期33卷 386-398页

作者： li Bing Yating Gu Lanke Hu li Bowen Yang lihua Jue Wang Yue yin Northwestern Polytechnical University Xi'an 710072China China Academy of Information and Communications Technology Beijing 100191China China Intelligent and Connected Vehicles(Beijing)Research Institute Co. LtdBeijing 100176China The 20th Research Institute of China Electronic Technology Group Corporation Xi’an 710068China Xidian University Xi'an 710071China

One of the major challenges arising in internet of military things(IoMT)is accommodating massive connectivity while providing guaranteed quality of service(QoS)in terms of ultra-high *** this regard,this paper presents a class of code-domain nonorthogonal multiple accesses(NOmas)for uplink ultra reliable networking of massive IoMT based on tactical datalink such as link-16 and joint tactical information distribution system(JTIDS).In the considered scenario,a satellite equipped with Nr antennas servers K devices including vehicles,drones,ships,sensors,handset radios,*** coded modulation,a special form of multiple input multiple output(MIMO)-NOma is *** discussion starts with evaluating the output signal to interference-plus-noise(SINR)of receiver filter,leading to the unveiling of a closed-form expression for overloading systems as the number of users is significantly larger than the number of devices admitted such that massive connectivity is *** expression allows for the development of simple yet successful interference suppression based on power allocation and phase shaping techniques that maximizes the sum rate since it is equivalent to fixed-point programming as can be *** proposed design is exemplified by nonlinear modulation schemes such as minimum shift keying(MSK)and Gaussian MSK(GMSK),two pivotal modulation formats in IoMT standards such as link-16 and *** results show that near capacity performance is ***,the performance is obtained using simple forward error corrections(FECs)of higher coding rate than existing schemes do,while the transmit power is reduced by 6 *** proposed design finds wide applications not only in IoMT but also in deep space communications,where ultra reliability and massive connectivity is a keen concern.

关键词： Satellite network Deep space communications Internet of military things Non-orthogonal multiple access MIMO link-16 JITDS

Rapid chemical recycling of waste polyester plastics catalyzed by recyclable catalyst

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Green Chemical Engineering 2024年第2期5卷 257-265页

作者： Yu-Ji Luo Jia-yin Sun Zhi li School of Physical Science and Technology ShanghaiTech UniversityShanghai201210China

Waste plastics are serious environmental threats due to their low degradability and low recycling *** and efficient waste plastics recycling technologies are urgently demanded for a sustainable ***,we report a rapid,closed-loop,and streamlined process to convert polyesters such as poly(ethylene terephthalate)(PET)back to its purified *** trifluoromethanesulfonic acid or metal triflates as the recyclable catalyst,polyesters such as PET can be completely depolymerized by simple carboxylic acids within 1 *** coupling this acidolysis with a subsequent hydrogenolysis process,the consumed carboxylic acid was recovered and the closed-loop of PET depolymerization could be *** catalysts and depolymerization agents are fully recycled while only PET and hydrogen are consumed.

关键词： Chemical recycling Waste polyester plastics Acidolysis Recyclable catalyst

Near-infrared non-fused electron acceptors for efficient organic photovoltaics

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Chinese Chemical Letters 2024年第4期35卷 436-441页

作者： Wenxiang ma Xinyu He Tianyi Chen De-li ma Hongzheng Chen Chang-Zhi li State Key Laboratory of Silicon and Advanced Semiconductor materials Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Developing narrow-bandgap organic semiconductors is important to facilitate the advancement of organic photovoltaics(OPVs). Herein, two near-infrared non-fused ring acceptors(NIR NFRAs), PTBFTT-F and PTBFTT-Cl have been developed with A-π_A-π_D-D-π_D-π_A-A non-fused structures. It is revealed that the introduction of electron deficient π-bridge(π_A) and multiple intramolecular noncovalent interactions effectively retained the structural planarity and intramolecular charge transfer of NFRAs, extending strong NIR photon absorption up to 950 nm. Further, the chlorinated acceptor, with the enlarged π-surface compared to the fluorinated counterpart, promoted not only molecular stacking in solid, but also the desirable photochemical stability in ambient, which are helpful to thereby improve the exciton and charge dynamics for the corresponding OPVs. Overall, this work provides valuable insights into the design of NIR organic semiconductors.

关键词： Organic photovoltaic Near-infrared Non-fused electron acceptor Noncovalent interaction Stability

Vision-Based Adaptive Prescribed-Time Control of UAV for Uncooperative Target Tracking with Performance Constraint

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Journal of Systems Science & Complexity 2024年第5期37卷 1956-1977页

作者： SHE Xuehua ma Hui REN Hongru li Hongyi School of Automation and the Guangdong Provincial Key Laboratory of Intelligent Decision and Cooperative Control Guangdong University of TechnologyGuangzhou 510006China School of mathematics and Statistics Guangdong University of TechnologyGuangzhou 510006China College of Electronic and Information Engineering and Chongqing Key Laboratory of Generic Technology and System of Service Robots Southwest UniversityChongqing 400715China

This paper discusses the uncooperative target tracking control problem for the unmanned aerial vehicle(UAV)under the performance constraint and scaled relative velocity constraint,in which the states of the uncooperative target can only be estimated through a vision *** the limited detection range,a prescribed performance function is designed to ensure the transient and steady-state performances of the tracking ***,the scaled relative velocity constraint in the dynamic phase is taken into account,and a time-varying nonlinear transformation is used to solve the constraint problem,which not only overcomes the feasibility condition but also fails to violate the constraint ***,the practically prescribed-time stability technique is incorporated into the controller design procedure to guarantee that all signals within the closed-loop system are *** is proved that the UAV can follow the uncooperative target at the desired relative position within a prescribed time,thereby improving the applicability of the vision-based tracking *** results have been presented to prove the validity of the proposed control strategy.

关键词： Nonlinear transformation performance constraint prescribed-time tracking uncooperative target vision-based measurement

Fast source mask co-optimization method for high-NA EUV lithography

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Opto-Electronic Advances 2024年第4期7卷 44-54页

作者： Ziqi li lisong Dong Xu ma Yayi Wei EDA Center Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029China Key Laboratory of Photoelectronic Imaging Technology and System of Ministry of Education of China School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China Guangdong Greater Bay Area Applied Research Institute of Integrated Circuit and Systems Guangzhou 510700China

Extreme ultraviolet(EUV)lithography with high numerical aperture(NA)is a future technology to manufacture the integrated circuit in sub-nanometer ***,source mask co-optimization(SMO)is an extensively used approach for advanced lithography process beyond 28 nm technology *** work proposes a novel SMO method to improve the image fidelity of high-NA EUV lithography system.A fast high-NA EUV lithography imaging model is established first,which includes the effects of mask three-dimensional structure and anamorphic ***,this paper develops an efficient SMO method that combines the gradient-based mask optimization algorithm and the compressivesensing-based source optimization algorithm.A mask rule check(MRC)process is further proposed to simplify the optimized mask *** illustrate that the proposed SMO method can significantly reduce the lithography patterning error,and maintain high computational efficiency.

关键词： computational lithography high-NA EUV lithography source-mask co-optimization lithography imaging model

Analysis of piezoelectric semiconductor fibers under gradient temperature changes

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Applied mathematics and Mechanics(English Edition) 2024年第2期45卷 311-320页

作者： Shuangpeng li Ruoran CHENG Nannan ma Chunli ZHANG Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China

Piezoelectric semiconductors(PSs)possess both semiconducting properties and piezoelectric coupling effects,making them optimal building blocks for semiconductor *** fiber-like structures have wide applications in multi-functional semiconductor *** this paper,a one-dimensional(1D)theoretical model is established to describe the piezotronic responses of a PS fiber under gradient temperature *** theoretical model aims to explain the mechanism behind the resistance change caused by such gradient temperature *** results demonstrate that a gradient temperature change significantly affects the physical fields within the PS fiber,and can induce changes in its surface *** provides important theoretical guidance on the development of piezotronic devices that are sensitive to temperature effects.

关键词： piezoelectric semiconductor(PS)fiber one-dimensional(1D)model piezotronic effect gradient temperature change