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Chinese Chemical Letters 2011年第3期22卷 272-275页

作者： jun hang jiang Xue Fei Liu Can Hui Zhen You jun Zhou Ju Zhu Jia Guo Lv Chun Quan Sheng Department of Medicinal Chemistry School of Pharmacy Second Military Medical University Shanghai 200433 China

A series of 7-azaindol derivatives were designed based on the homologous 3D model of human *** compounds were synthesized and evaluated for their human acrosin inhibitory activities in *** 7a,7i,7j,7k and 7n showed highly inhibitory activity against human *** three-dimensional structure-activity relationship was investigated through a CoMFA model,which provided valuable information to further study of potential human acrosin inhibitors.

关键词： Rational design Azaindole Synthesis Acrosin CoMFA

Acidic rearrangement of benzyl group in flavone benzyl ethers and its regioselectivity

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Chinese Chemical Letters 2015年第6期26卷 793-796页

作者： Chong-Qing Wang Xin Chen jun-hang jiang Hui Tang Kong-Kai Zhu You-jun Zhou Can-Hui Zheng Ju Zhu School of Pharmacy Second Military Medical University School of Biology and Pharmaceutical Engineering Wuhan Polytechnic University Pharmacy Provincial Hospital Affiliated to Shandong University State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences

The benzyl-substituted flavone compounds are rare in nature, while some of which have interesting biological activities. The total synthesis of benzyl-substituted flavone derivatives via the acidic rearrangement of benzyl groups in flavone benzyl ethers, and the complicated regioselectivity of the rearrangement were reported. The regioselectivity was proposed to be determined by the steric hindrance as well as the ease of electrophilic substitution reaction for benzyl cations at different positions of corresponding debenzylated fiavone compounds.

关键词： Benzyl-substituted flavone Acidic rearrangement of benzyl group Regioselectivity Quantum chemical calculation

Supporting-electrolyte-free electrochemical[2+2+1]annulation of benzo[d]isothiazole 1,1-dioxides,N-arylglycines and paraformaldehyde

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Chinese Chemical Letters 2024年第6期35卷 327-330页

作者： Hai-Yang Song jun jiang Yu-hang Song Min-hang Zhou Chao Wu Xiang Chen Wei-Min He School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

The H-bond promoted electrochemical[2+2+1]annulation of benzo[d]isothiazole 1,1-dioxides,Narylglycines and paraformaldehyde for the synthesis of various benzo[d]imidazo[1,5-b]isothiazole 5,5-dioxide derivatives under ... 详细信息

关键词： H-bond N-Arylglycines Paraformaldehyde Organic electro-synthesis Electrolyte-free

Synthesis and biological evaluation of 5,6,7-trimethoxy-1-benzylidene-3,4-dihydro-naphthalen-2-one as tubulin-polymerization inhibitors

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Chinese Chemical Letters 2015年第5期26卷 607-609页

作者： jun-hang jiang Can-Hui Zheng Chong-Qing Wang Juan Wang Wei Tian Chao Yang Yun-Long Song Yong Hu Ju Zhu You-Yun Zhou School of Pharmacy Second Military Medical University Shanghai Institute of Pharmaceutical Industry Department of Neonatology Shanghai Children's HospitalShanghai Jiao Tong University

A series of new combretastatin-A4 analogs were synthesized, in which a six-membered ring connects the linking bridge and A ring, and their tumor cell growth and tubulin-polymerization inhibitory activity were evaluated. These compounds appear to be potential tubulin-polymerization inhibitors, Compounds 1b with amino substituted on position 3 of B ring conferred optimal bioactivity, higher than that of the lead compound 22b and equivalent to that of CA-4. The binding modes of these compounds to tuhulin were obtained by molecular docking, which can explain the structure-activity relationship. The studies presented here provide a new structural type for the development of novel antitumor agents.

关键词： Tubulin polymerization inhibitor Antitumor agent Combretastatin-A4 analog

Strength and ductility optimization of HPDC AlSi8MgCuZn2 alloys by modifying pre-aging treatment

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China Foundry 2024年第4期21卷 343-351页

作者： Yuan-hang jiang Hui-ting Zheng Fei Liu Hai-dong Zhao National Engineering Research Center of Near-net Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510641China

Considering the components produced by high pressure die casting(HPDC)process usually with ultra-large sizes and complex morphologies,high temperature solid solution treatment is not a suitable method to further improve their mechanical *** this study,two-stage aging treatment with different pre-aging times was designed and employed to further improve the mechanical properties of HPDC Al8SiMgCuZn *** characteristics of precipitates were evaluated by a transmission electron microscope(TEM),and the precipitation strengthening mechanism was *** results reveal that the strengthening is mainly contributed by the precipitation ofβ″phase after two-stage aging,and the number density and size of the precipitates are significantly depended on the pre-aging *** number density of precipitates is increased with the pre-aging time prolonged from 0 h to 4 h,and then decreases with the further increase of pre-aging time from 4 h to 6 *** precipitates with the highest density and smallest size are observed after pre-aging for 4 *** pre-aged at 100℃for 4 h and then artificial aged at 200℃for 30 min,the yield strength of 207 MPa,ultimate tensile strength of 325 MPa and elongation of 7.6%are achieved.

关键词： high pressure die cast aluminum alloy microstructural heterogeneity mechanical properties precipitation strengthening two-stage aging

Noteworthy phenomena in pediatric inherited cardiomyopathy

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World Journal of Pediatrics 2024年第6期20卷 635-637页

作者： Jin-hang jiang Jie Tian Bo Pan Department of Pediatric Cardiology National Clinical Key Cardiovascular SpecialtyNational Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChildren's Hospital of Chongqing Medical University136 Zhongshan Er RoadYuzhong DistirctChongqing 400014China Key Laboratory of Children's Important Organ Development and Diseases Chongqing Municipal Health CommissionChongqingChina

Pediatric cardiomyopathy has an early onset and poor ***,it was referred to as idiopathic cardiomyopathy due to unknown ***,recent advances in molecular genetics and molecular biology have demonstrated that most pediatric cardiomyopathy cases are related to genetic factors,mainly involving single gene and single nucleotide mutations[1,2].Although the pathogenicity of some gene mutations in patients has not been fully elucidated,genetic factors are still considered the main cause of pediatric cardiomyopathy.

关键词： cardiomyopathy pediatric etiology

PEPFL:A framework for a practical and efficient privacy-preserving federated learning

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Digital Communications and Networks 2024年第2期10卷 355-368页

作者： Yange Chen Baocang Wang hang jiang Pu Duan Yuan Ping Zhiyong Hong State Key Laboratory of Integrated Service Networks Xidian UniversityXi'an710071China School of Information Engineering Xuchang UniversityXuchang461000China School of Telecommunications Engineering Xidian UniversityXi'an710071China Secure Collaborative Intelligence Laboratory Ant GroupHangzhou310000China Facility of Intelligence Manufacture Wuyi UniversityJiangmen529020China

As an emerging joint learning model,federated learning is a promising way to combine model parameters of different users for training and inference without collecting users’original ***,a practical and efficient solution has not been established in previous work due to the absence of efficient matrix computation and cryptography schemes in the privacy-preserving federated learning model,especially in partially homomorphic *** this paper,we propose a Practical and Efficient Privacy-preserving Federated Learning(PEPFL)***,we present a lifted distributed ElGamal cryptosystem for federated learning,which can solve the multi-key problem in federated ***,we develop a Practical Partially Single Instruction Multiple Data(PSIMD)parallelism scheme that can encode a plaintext matrix into single plaintext for encryption,improving the encryption efficiency and reducing the communication cost in partially homomorphic *** addition,based on the Convolutional Neural Network(CNN)and the designed cryptosystem,a novel privacy-preserving federated learning framework is designed by using Momentum Gradient Descent(MGD).Finally,we evaluate the security and performance of *** experiment results demonstrate that the scheme is practicable,effective,and secure with low communication and computation costs.

关键词： Federated learning Partially single instruction multiple data Momentum gradient descent ElGamal Multi-key Homomorphic encryption

Understanding adversarial attacks on observations in deep reinforcement learning

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Science China(Information Sciences) 2024年第5期67卷 69-83页

作者： You QIAOBEN Chengyang YING Xinning ZHOU hang SU jun ZHU Bo Zhang Department of Computer Science and Technology Beijing National Research Center for Information Science and Technology Tsinghua-Bosch Joint Center for Machine Learning Institute for Artificial Intelligence Tsinghua University Peng Cheng Laboratory

Deep reinforcement learning models are vulnerable to adversarial attacks that can decrease the cumulative expected reward of a victim by manipulating its observations. Despite the efficiency of previous optimization-based methods for generating adversarial noise in supervised learning, such methods might not achieve the lowest cumulative reward since they do not generally explore the environmental ***, a framework is provided to better understand the existing methods by reformulating the problem of adversarial attacks on reinforcement learning in the function space. The reformulation approach adopted herein generates an optimal adversary in the function space of targeted attacks, repelling them via a generic two-stage framework. In the first stage, a deceptive policy is trained by hacking the environment and discovering a set of trajectories routing to the lowest reward or the worst-case performance. Next, the adversary misleads the victim to imitate the deceptive policy by perturbing the observations. Compared to existing approaches, it is theoretically shown that our adversary is strong under an appropriate noise level. Extensive experiments demonstrate the superiority of the proposed method in terms of efficiency and effectiveness, achieving state-of-the-art performance in both Atari and MuJoCo environments.

关键词： deep learning reinforcement learning adversarial robustness adversarial attack

Regulation of rhizosphere microenvironment by rice husk ash for reducing the accumulation of cadmium and arsenic in rice

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Journal of Environmental Sciences 2024年第2期136卷 1-10页

作者： Yi jiang Ya Liu Xuantao Yi Peng Zeng Bohan Liao hang Zhou Jiaofeng Gu College of Environmental Science and Engineering Central South University of Forestry and TechnologyChangsha 410004China Hunan Engineering Laboratory for Control of Rice Quality and Safety Changsha 410004China

It is important to reduce Cd and As content in brown rice in contaminated paddy *** conducted research on the effects of rice husk ash (RHA) on the Cd and As in the rhizosphere microenvironment (soil,porewater,and iron plaque) and measured the Cd,As,and Si content in rice *** main elements in RHA were Si (29.64%) and O (69.17%),which had the maximum adsorption capacity for Cd was 42.49 mg/kg and for As was 18.62 mg/*** pH and available Si content increased,while soil available Cd and As decreased following application of 0.5%–2%*** promote the transformation of Cd to insoluble fraction,while As was transformed from a poorly soluble form to a more active *** reduced Cd content and increased Si content in porewater,and reduced As only at the later rice growth *** increased the amount of iron plaque,thereby decreasing the Cd content in iron plaque,while increased the As content in *** and inorganic As content in brown rice were decreased,to 0.31 mg/kg and 0.18 mg/kg,*** decrease of Cd in brown rice was due to the decrease of Cd mobility in soil,thereby reducing root accumulation,while the decrease of As in brown rice was affected by the transport from roots to ***,RHA can be considered as a safe and efficient in-situ remediation amendment for Cd and As co-contaminated paddy soil.

关键词： Rice husk ash(rha) Cadmium Arsenic Silicon Rice Soil

Breaking the Fe_(3)O_(4)-wrapped copper microstructure to enhance copper-slag separation

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2312-2325页

作者： Xiaopeng Chi Haoyu Liu jun Xia hang Chen Xiangtao Yu Wei Weng Shuiping Zhong Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China Fujian Key Laboratory of Green Extraction and High-Value Utilization of New Energy Metals Fuzhou UniversityFuzhou 350108China Zijin Mining Group Co. Ltd.Longyan 364200China Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China

The precipitation of Fe_(3)O_(4)particles and the accompanied formation of Fe_(3)O_(4)-wrapped copper structure are the main obstacles to copper recovery from the molten slag during the pyrometallurgical smelting of copper ***,the commercial powdery pyrite or anthracite is replaced with pyrite-anthracite pellets as the reductants to remove a large amount of Fe_(3)O_(4)particles in the molten slag,resulting in a deep fracture in the Fe_(3)O_(4)-wrapped copper microstructure and the full exposure of the copper matte *** 1wt%composite pellet is used as the reductant,the copper matte droplets are enlarged greatly from 25μm to a size observable by the naked eye,with the copper content being enriched remarkably from 1.2wt%to 4.5wt%.Density functional theory calculation results imply that the formation of the Fe_(3)O_(4)-wrapped copper structure is due to the preferential adhesion of Cu_(2)S on the Fe_(3)O_(4)particles.X-ray photoelectron spectroscopy,Fourier transform infrared spectrometer(FTIR),and Raman spectroscopy results all reveal that the high-efficiency conver-sion of Fe_(3)O_(4)to FeO can decrease the volume fraction of the solid phase and promote the depolymerization of silicate network *** a consequence,the settling of copper matte droplets is enhanced due to the lowered slag viscosity,contributing to the high efficiency of copper-slag separation for copper *** results provide new insights into the enhanced in-situ enrichment of copper from mol-ten slag.

关键词： pyrometallurgical smelting process slag cleaning reductants copper matte