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Preface to"Advanced Characterization Technique in Electrocatalysis and Photocatalysis"

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Chinese Journal of Structural Chemistry 2022年第10期41卷 1-1页

作者： Zheng Jiang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China Universtyof Chinese Academy of Sciences Bejing 100049China Shanghar Synchrotron Rediation Facility Shanghai Advanced Research IisteChinese Acadlemy of SciencesShanghai 201204China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China

The severe burning of fossil fuels brings about a worsening energy crisis and environmental issues which aroused global concern.Electrocatalysis and photocatalysis are promising approaches to store intermittent renewa... 详细信息

关键词： store Electrocatalysis catalysis

Thermoelastic topology optimization for structures with temperature-dependent material properties

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Science China(Technological Sciences) 2023年第12期66卷 3488-3503页

作者： zheng Jing RONG XuanPei jiang Chao State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body School of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

A thermoelastic topology optimization is proposed for structures with temperature-dependent material properties.Different from the common assumption of constant material properties in traditional thermoelastic topology optimization,the temperaturedependent material properties related to mechanical and thermal fields are taken into account.The non-uniform temperature distribution of the structure is a design dependent field that may vary during the optimization,and the nonlinear heat transfer analysis is considered according to the large temperature gradient.Based on these,a thermoelastic topology optimization model considering temperature-dependent material properties is formulated.The sensitivities with respect to the design variables are derived and the Method of Moving Asymptotes(MMA)algorithm is used to update the topological design variables.A cooperation platform based on MATLAB and ABAQUS is developed for the proposed thermoelastic topology optimization method to deal with problems with arbitrary domains for the design of complex engineering structures.Several typical numerical examples are given to illustrate the effectiveness of the proposed method and show the important influence of the temperaturedependent material properties.

关键词： thermoelastic topology optimization nonlinear heat transfer temperature-dependent material properties

A PERT-BiLSTM-Att Model for Online Public Opinion Text Sentiment Analysis

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Intelligent Automation & Soft Computing 2023年第8期37卷 2387-2406页

作者： Mingyong Li Zheng Jiang Zongwei Zhao Longfei Ma College of Computer and Information Science Chongqing Normal UniversityChongqing401331China

As an essential category of public event management and control,sentiment analysis of online public opinion text plays a vital role in public opinion early warning,network rumor management,and netizens’person-ality portraits under massive public opinion data.The traditional sentiment analysis model is not sensitive to the location information of words,it is difficult to solve the problem of polysemy,and the learning representation ability of long and short sentences is very different,which leads to the low accuracy of sentiment classification.This paper proposes a sentiment analysis model PERT-BiLSTM-Att for public opinion text based on the pre-training model of the disordered language model,bidirectional long-term and short-term memory network and attention mechanism.The model first uses the PERT model pre-trained from the lexical location information of a large amount of corpus to process the text data and obtain the dynamic feature representation of the text.Then the semantic features are input into BiLSTM to learn context sequence information and enhance the model’s ability to represent long sequences.Finally,the attention mechanism is used to focus on the words that contribute more to the overall emotional tendency to make up for the lack of short text representation ability of the traditional model,and then the classification results are output through the fully connected network.The experimental results show that the classification accuracy of the model on NLPCC14 and weibo_senti_100k public data sets reach 88.56%and 97.05%,respectively,and the accuracy reaches 95.95%on the data set MDC22 composed of Meituan,Dianping and Ctrip comment.It proves that the model has a good effect on sentiment analysis of online public opinion texts on different platforms.The experimental results on different datasets verify the model’s effectiveness in applying sentiment analysis of texts.At the same time,the model has a strong generalization ability and can achieve good results for sentiment analysis of datasets in different

关键词： Natural language processing PERT pre-training model emotional analysis BiLSTM

Integrated Sensing and Communication Enabled Multiple Beamwidth and Power Allocation for Connected Automated Vehicles

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中国通信:英文版 2023年第9期20卷 46-58页

作者： Shengnan Liu Qianyi Hao Qixun Zhang Jiaxiang Liu Zheng Jiang China Telecom Corporation Limited Beijing Research Institute Beijing 102209China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Connected autonomous vehicles(CAVs)are a promising paradigm for implementing intelligent transportation systems.However,in CAVs scenarios,the sensing blind areas cause serious safety hazards.Existing vehicle-to-vehicle(V2V)technology is difficult to break through the sensing blind area and ensure reliable sensing information.To overcome these problems,considering infrastructures as a means to extend the sensing range is feasible based on the integrated sensing and communication(ISAC)technology.The mmWave base station(mmBS)transmits multiple beams consisting of communication beams and sensing beams.The sensing beams are responsible for sensing objects within the CAVs blind area,while the communication beams are responsible for transmitting the sensed information to the CAVs.To reduce the impact of inter-beam interference,a joint multiple beamwidth and power allocation(JMBPA)algorithm is proposed.By maximizing the communication transmission rate under the sensing constraints.The proposed non-convex optimization problem is transformed into a standard difference of two convex functions(D.C.)problem.Finally,the superiority of the lutions.The average transmission rate of communication beams remains over 3.4 Gbps,showcasing a significant improvement compared to other algorithms.Moreover,the satisfaction of sensing services remains steady.

关键词： integrated sensing and communication connected automated vehicles resource allocation in wireless networks

Influence of Narrative Strategies on Fundraising Outcome:An Exploratory Study of Online Medical Crowdfunding

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Journal of Social Computing 2022年第4期3卷 303-321页

作者： Lu zheng Lihui jiang Department of Sociology Tsinghua UniversityBeijing 100084China

Online medical crowdfunding(OMC)has attracted massive attention and participation in China.Despite its goal to lift the financial burden caused by expensive medical expenditure,little has been done to evaluate its impact on healthcare inequality.We examine the social consequences of OMC based on a large random sample extracted from one of the most widely-used OMC platforms in China.Our analysis shows that a disproportionally high percentage of fundraising campaigns are launched for patients with low socioeconomic status suffering from various illnesses,including many rare diseases.These findings suggest that OMC plays a positive role in providing an alternative channel for disadvantaged patients under the current health insurance system.We further examine whether and the extent to which the narrative style of solicitation text—fundraising campaign description—influences fundraising outcomes using natural language processing(NLP).The results show that expressions conveying optimism tend to result in a higher completion ratio,whereas descriptions engaging in moral mobilization or focusing on financial burden tend to have a negative impact on fundraising outcomes.

关键词： online medical crowdfunding(OMC) narrative fundraising outcome healthcare inequality

Comparative Study of the Rock-breaking Mechanism of a Disc Cutter and Wedge Tooth Cutter by Discrete Element Modelling

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 269-285页

作者： Hua jiang Huiyan Zhao Xiaoyan Zhang Yusheng jiang Yaofu zheng School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing 100083China Beijing Urban Construction Group Co. Ltd.Beijing 100088China

The operation of a shield tunnel boring machine(TBM)in a high-strength hard rock stratum results in significant cutter damage,adversely affecting the thrust and torque of the cutter head.Therefore,it is very important to carry out the research on the stress characteristics and optimize the cutter parameters of cutters break high-strength hard rock.In this paper,the rock-breaking performance of cutters in an andesite stratum in the tunnel of Qingdao Metro Line No.8 was investigated using the discrete element method and theoretical analysis.The rock-breaking processes of a disc cutter and wedge tooth cutter were simulated by software particle flow code PFC^(3D),and the rock-breaking degree,stress of the cutter,and rock-breaking specific energy were analyzed.The rock damage caused by the cutter in a specific section was divided into three stages:the advanced influence,crushing,and stabilizing stages.The rock-breaking degree and the tangential and normal forces of the wedge tooth cutter are larger than that of the disc cutter under the same conditions.The disc cutter(wedge tooth cutter)has the highest rock-breaking efficiency at a cutter spacing of 100 mm(110 mm)and a penetration depth of 8 mm(10 mm),and the rock-breaking specific energy is 11.48 MJ/m^(3)(12.05 MJ/m^(3)).Therefore,two types of cutters with different penetration depths or cutter spacing should be considered.The number of teeth of wedge tooth cutters can be increased in hard strata to improve the rock-breaking efficiency of the shield.The research results provide a reference for shield cutterhead selection and cutter layout in similar projects.

关键词： Qingdao andesite Rock breaking with cutter Wedge tooth cutter Specific energy PFC^(3D)

Improving the prognosis of pancreatic cancer:insights from epidemiology,genomic alterations,and therapeutic challenges

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Frontiers of Medicine 2023年第6期17卷 1135-1169页

作者： Zhichen jiang Xiaohao zheng Min Li Mingyang Liu State Key Laboratory of Molecular Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of General Surgery Division of Gastroenterology and PancreasZhejiang Provincial People's HospitalAffiliated People's HospitalHangzhou Medical CollegeHangzhou 310014China Department of Pancreatic and Gastric Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of General Surgery Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Medicine The University of Oklahoma Health Sciences CenterOklahoma CityOK 73104USA

Pancreatic cancer,notorious for its late diagnosis and aggressive progression,poses a substantial challenge owing to scarce treatment alternatives.This review endeavors to furnish a holistic insight into pancreatic cancer,encompassing its epidemiology,genomic characterization,risk factors,diagnosis,therapeutic strategies,and treatment resistance mechanisms.We delve into identifying risk factors,including genetic predisposition and environmental exposures,and explore recent research advancements in precursor lesions and molecular subtypes of pancreatic cancer.Additionally,we highlight the development and application of multi-omics approaches in pancreatic cancer research and discuss the latest combinations of pancreatic cancer biomarkers and their efficacy.We also dissect the primary mechanisms underlying treatment resistance in this malignancy,illustrating the latest therapeutic options and advancements in the field.Conclusively,we accentuate the urgent demand for more extensive research to enhance the prognosis for pancreatic cancer patients.

关键词： pancreatic cancer cancer screening single cell molecular alterations precancerous lesion therapy resistance

A novel redox indicator based on relative abundances of C_(31) and C_(32) homohopanes in the Eocene lacustrine Dongying Depression, East China

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Petroleum Science 2022年第4期19卷 1494-1504页

作者： Chong jiang Hai-Ping Huang zheng Li Hong Zhang zheng Zhai School of Energy Resource China University of Geosciences(Beijing)Beijing100083China School of Geosciences Yangtze UniversityWuhanHubei430100China Department of Geoscience University of CalgaryCalgaryAlbertaT2N 1N4Canada Geology Scientific Research Institute of Shengli Oilfield Company SinopecDongyingShandong 257015China

A suite of oils and bitumens from the Eocene Shahejie Formation(Es) in Dongying Depression was geochemically characterized to illustrate impact of source input and redox conditions on distributions of pentacyclic terpanes. The Es_(4) developed under highly reducing, sulfidic hypersaline conditions, while Es_(3) formed under dysoxic, brackish to freshwater conditions. Oils derived from Es_(4) are enriched in C_(32) homohopanes(C_(32) H), while those from Es_(3) are prominently enriched in C_(31) homohopanes(C_(31) H). The C_(32) H/C_(31) H ratio shows positive correlation with homohopane index(HHI), gammacerane index, and negative correlation with pristane/phytane ratio, and can be used to evaluate oxic/anoxic conditions during deposition. High C32 H/C_(31) H ratio(> 0.8) is an important characteristic of oils derived from anoxic environments, while low values(< 0.8) indicate dysoxic conditions and extremely low values(< 0.4)indicate strong oxic conditions. The C_(32) H/C_(31) H ratio can be applied for deposition condition diagnosis because carboxyl group of C_(32) hopanoic acids might be reduced to C_(32) homohopanes under anoxic conditions, and oxidized to C_(31) homohopane under oxic conditions. Advantages to use C_(32) H/C_(31) H ratio as redox condition proxy compared to the HHI and gammacerane indexes are wider valid maturity range,less sensitive to biodegradation influence and better differentiating reducing from oxic environments.

关键词： paper Biomarkers C_(32)/C_(31)homohopane ratio Redox conditions Dongying Depression

Green Synthesis of Nitrogen-to-Ammonia Fixation: Past, Present, and Future

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Energy & Environmental Materials 2022年第2期5卷 452-457页

作者： Jianyun zheng Li jiang Yanhong Lyu San Ping jiang Shuangyin Wang State Key Laboratory of Chem/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Department of Educational Science Hunan First Normal UniversityChangsha 410205China Curtin University Perth WAAustralia

The nitrogen(N2)-to-ammonia(NH3)fixation driven by renewable energy has an attractive prospect to relieve the global warming and reduce the consumption of fossil fuels.Ideally,photocatalytic,electrochemical,and photoelectrochemical approaches are developed as the next-generation NH3 synthesis technologies to substitute the Haber–Bosch method.However,the NH3 yield rate of nitrogen reduction reaction(NRR)by green approaches is extremely low,resulting in the current dilemma of NRR and contamination issues.Thus,in this mini review,the past advances on the sustainable NRR are briefly summarized in the three aspects as follows:the selectivity and adjustment of various catalysts,the type of electrolyte/solvent system,and the investigation of reaction conditions.Subsequently,the recent critical activities in the area of sustainable NH3 synthesis are analyzed and discussed deeply,and a perspective for rational and healthy development of this area is provided positively。

关键词： current dilemma enhanced performances future challenges green synthesis nitrogen-to-ammonia fixation