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Chinese Journal of Chemistry 2024年第3期42卷 235-242页

作者： Chun Tang Shengjie Zhang Zhengyu lu qian Li Ming luo Dafa Chen Haiping Xia State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringCollaborative Innovation Center of Chemistry for Energy MaterialsXiamen UniversityXiamenFujian361005 China Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong518055 China

Metallacyclopentadienes are important metallacycles and regarded as intermediates in many reactions,therefore,new methods to achieve them are *** this study,a formal[3+2]method,through the reactions of an osmapentalyne with benzyl carbanions,was *** reactions underwent a nucleophilic attack of carbanions to the Os≡C bond,followed by C—H activation to form the five-membered osmacyclopentadiene *** of the reactions were carried out at room temperature,the substituents on the aromatic rings of benzyl carbanions are diverse,and the resulting products contain an Os—H bond,representing a novel type of 10C-carbolong *** work provides a new convenient route to construct metallacyclopentadienes,which is expected to further promote the development of such a type of substances.

关键词： Metallacyclopentadiene Carbolong chemistry Osmium C–H activation Nucleophilic addition

Highly crystallization-induced emissive luminophores with mechanoluminescent features for two-photon harvesting fluorescence imaging and latent fingerprint identification

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Nano Research 2024年第7期17卷 6475-6482页

作者： Jian lu Juan Gao Rui-Xuan qian Shuai-Hua Wang Fa-Kun Zheng Guo-Cong Guo Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Fluorescence imaging can be employed in fields of medical treatment,astronomical exploration,and national defense *** fluorescence imaging often takes the single-photon techniques,which is vulnerable to background interference and ***,two-photon fluorescence imaging can achieve much higher-resolution fluorescence imaging for reducing scattering and deeper ***,by assembling the tetraphenylethylene backbones with nontoxic and non-noble K^(+)ions,compound 1([(Hdma)K(H_(2)ettc)]_(n),H_(4)ettc=4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'-biphenyl]-4-carboxylic acid)))with the crystallization-induced emissions exhibited charming fluorescence imaging under two-photon excitation microscopy(TPEM).Besides,luminescent powders based on compound 1 can achieve high-resolution fingerprint recognition,providing secure access control and identification for a novel authentication *** with the commercial fluorescent dyes coumarin-6,the as-synthesized compound 1 showed great solvent stability,indicating its durability against harsh ***,compound 1 shows mechanoluminescent properties for the perturbation of weak supramolecular interactions within ordered arrangements of the H_(2)ettc^(2−)*** novel compound has provided an important insight to the development of twophoton fluorescence imaging and advanced external-stimuli responsive materials.

关键词： crystallization-induced emission fluorescence imaging two-photon absorption fingerprint recognition mechanoluminescence

Deep-learning-assisted online surface roughness monitoring in ultraprecision fly cutting

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Science China(Technological Sciences) 2024年第5期67卷 1482-1497页

作者： SHEHZAD Adeel RUI XiaoTing DING YuanYuan ZHANG JianShu chang Yu lu HanJing CHEN YiHeng Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjing210094China National Key Laboratory of Complex Multibody System Dynamics Nanjing210094China Automotive Engineering Centre University of Engineering and TechnologyLahore54890Pakistan School of Science Nanjing University of Science and TechnologyNanjing210094China College of Engineering Peking UniversityBeijing100871China

Surface roughness is one of the most critical attributes of machined components,especially those used in high-performance *** surface roughness monitoring offers advancements comparable to post-process inspection methods,reducing inspection time and costs and concurrently reducing the likelihood of ***,online monitoring approaches for surface roughness are constrained by several limitations,including the reliance on handcrafted feature extraction,which necessitates the involvement of human experts and entails time-consuming ***,the prediction models trained under one set of cutting conditions exhibit poor performance when applied to different experimental *** address these challenges,this work presents a novel deep-learning-assisted online surface roughness monitoring method for ultraprecision fly cutting of copper workpieces under different cutting *** acceleration signals were acquired during each cutting experiment to develop two datasets,and no handcrafted features were *** deep learning models were developed and evaluated using standard performance metrics.A convolutional neural network stacked on a long short-term memory network outperformed all other network models,yielding exceptional results,including a mean absolute percentage error as low as 1.51%and an R2value of 96.6%.Furthermore,the robustness of the proposed model was assessed via a validation cohort analysis using experimental data obtained using cutting parameters different from those previously *** performance of the model remained consistent and commendable under varied conditions,asserting its applicability in real-world scenarios.

关键词： online surface roughness monitoring UPFC deep learning CNN-LSTM vibration signal

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Organo-mineral complexes in soil colloids:Implications for carbon storage in saline-alkaline paddy soils from an eight-year field experiment

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Pedosphere 2024年第1期34卷 97-109页

作者： Mengmeng CHEN Shirong ZHANG lu LIU Baojian chang Yuyi LI Xiaodong DING College of Resources and Environment Qingdao Agricultural UniversityQingdao 266109China Jingke High-tech Institute of Environmental Sciences Co. LtdBeijing 100094China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China

The combination of organic carbon(OC) and reactive minerals is a crucial mechanism of soil carbon(C) storage, which is regulated by the formation of organo-mineral complexes on the surface of soil colloids. The effect of organic fertilizer on the storage mechanism of OC in soil colloids was studied through an 8-year field experiment, which included four treatments: i) no fertilization(control, CK), ii) only mineral N, P, and K fertilization(NPK), iii) NPK plus a low level(450 kg C ha^(-1)year^(-1)) of organic fertilization(NPKC1), and iv) NPK plus a high level(900 kg C ha^(-1)year^(-1)) of organic fertilization(NPKC2). The main results indicated that organic fertilizer addition significantly increased the content of aromatic-C, which was 158.7% and 140.0% higher in soil colloids than in bulk soil in the NPKC1 and NPKC2 treatments, respectively. X-ray photoelectron spectroscopy further demonstrated that the relative proportion of C=C group on the surface of soil colloids was increased by 20.1% and 19.1% in the NPKC1 and NPKC2 treatments, respectively,compared with the CK. In addition, compared with the NPK treatment, the content of reactive minerals(such as Fe and Al oxides) significantly increased with organic fertilization, which was positively correlated with C=C group in soil colloids. This indicates that aromatic-C may be retained by the formation of aromatic-mineral complexes with reactive minerals in soil colloids. Organic fertilization also significantly increased OC storage efficiency(OCSE), which was significantly higher in the NPKC1 treatment than in the NPKC2 treatment. Therefore, a moderate amount of organic fertilizer application is a better agronomic practice to increase OCSE and OC storage in saline-alkaline paddy soils.

关键词： aromatic-C aromatic-mineral complex organic fertilization reactive mineral soil organic carbon water-dispersible colloid

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A resonant high-pressure microsensor based on a composite pressure-sensitive mechanism of diaphragm bending and volume compression

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Microsystems & Nanoengineering 2024年第2期10卷 57-66页

作者： Pan qian Zongze Yu Jie Yu Yulan lu Bo Xie Jian Chen Deyong Chen Junbo Wang The State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing100190China The School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing100049China

In this paper,a composite pressure-sensitive mechanism combining diaphragm bending and volume compression was developed for resonant pressure microsensors to achieve high-pressure measurements with excellent *** composite mechanism was explained,and the sensor structure was designed based on theoretical analysis and finite element *** all-silicon resonant high-pressure microsensor with multiple miniaturized cavities and dual resonators was developed,where dual resonators positioned in two resonant cavities with suitably different widths are used to perform opposite characteristics in pressure and the same characteristics at different temperatures,which can improve pressure sensitivities and realize temperature self-compensation by differential frequency *** microsensor was fabricated by microfabrication,and the experimental results showed that the sensor had an accuracy of±0.015%full scale(FS)in a pressure range of 0.1~100 MPa and a temperature range of−10~50℃.The pressure sensitivity of the differential frequency was 261.10 Hz/MPa(~2523 ppm/MPa)at a temperature of 20℃,and the temperature sensitivities of the dual resonators were−1.54 Hz/℃(~−14.5 ppm/℃)and−1.57 Hz/℃(~−15.6 ppm/℃)at a pressure of 2 *** differential output had an outstanding stability within±0.02 Hz under constant temperature and ***,this research provides a convenient solution for high-pressure measurements because of its advantages,namely,large range,excellent accuracy and stability.

关键词： stability resonant bending

Synergistic effects of the entomopathogenic fungus Isaria javanica and low doses of dinotefuran on the efficient control of the rice pest Sogatella furcifera

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Journal of Integrative Agriculture 2024年第2期23卷 621-638页

作者： Tingting Zhou qian Zhao Chengzhou Li lu Ye Yanfang Li Nemat OKeyhani Zhen Huang Department of Entomology College of Plant ProtectionSouth China Agricultural UniversityGuangzhou 510642China Guangdong Provincial Key Laboratory of High Technology for Plant Protection Plant Protection Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510642China Department of Microbiology and Cell Science Institute of Food and Agricultural SciencesUniversity of FloridaFL 32611USA

The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza *** is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical *** investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on *** under both laboratory and field *** results show that *** displays high infection efficiency and mortality for different stages of ***,reducing adult survival,female oviposition and ovary *** bioassays showed that the combined use of *** with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in *** than the use of *** or dinotefuran *** combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase *** field trials,*** effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of *** populations using the combination of a low dose of ***(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days *** findings indicate that the entomogenous fungus *** offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.

关键词： Isaria javanica Sogatella furcifera entomopathogenic fungus white planthopper rice synergistic effect on pest control

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Improved hydrogen storage kinetics of MgH_(2) using TiFe_(0.92)Mn_(0.04)Co_(0.04) with in-situ generated α-Fe as catalyst

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Materials Reports(Energy) 2024年第1期4卷 95-103页

作者： Zefeng Li Yangfan lu Jingfeng Wang Yu'an Chen qian Li Fushen Pan College of Materials Science and Engineering National Engineering Research Center for Magnesium AlloysChongqing UniversityChongqing400044PR China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing400044PR China Chongqing Institute of New Energy Storage Materials and Equipment Chongqing401135PR China

While TiFe alloy has recently attracted attention as the efficient catalyst to enhance de/hydrogenation rates of Mg/MgH_(2),the difficulty of its activation characteristics has hindered further improvement of reaction ***,we report that the TiFe_(0.92)Mn_(0.04)Co_(0.04) catalyst can overcome the abovementioned *** synthesized MgH_(2)-30 wt% TiFe_(0.92)Mn_(0.04)Co_(0.04) can release 4.5 wt%of hydrogen in 16 min at 250℃,three times as fast as MgH_(2).The activation energy of dehydrogenation was as low as 84.6 kJ mol^(-1),which is 46.8%reduced from pure MgH_(2).No clear degradation of reaction rates and hydrogen storage capacity was observed for at least 30 *** studies reveal that TiFe_(0.92)Mn_(0.04)Co_(0.04) partially decomposes to in-situ generatedα-Fe particles dispersed on TiFe_(0.92)Mn_(0.04)Co_(0.04).The presence ofα-Fe reduces the formation of an oxide layer on TiFe_(0.92)Mn_(0.04)Co_(0.04),enabling the activation *** the same time,the hydrogen incorporation capabilities of TiFe_(0.92)Mn_(0.04)Co_(0.04) can provide more hydrogen diffusion paths,which promote hydrogen dissociation and *** discoveries demonstrate the advanced nature and importance of combining the in-situ generatedα-Fe with TiFe_(0.92)Mn_(0.04)Co_(0.04).It provides a new strategy for designing highly efficient and stable catalysts for Mg-based hydrogen storage materials.

关键词： Hydrogen storage materials Magnesium De/hydrogenation kinetics Catalyst

High-Precision Flow Numerical Simulation and Productivity Evaluation of Shale Oil Considering Stress Sensitivity

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Fluid Dynamics & Materials Processing 2024年第10期20卷 2281-2300页

作者： Mingjing lu Qin qian Anhai Zhong Feng Yang Wenjun He Min Li Petroleum Engineering Technology Research Institute of Shengli Oilfield SINOPECDongying257000China Postdoctoral Scientific Research Working Station of Shengli Oilfield SINOPECDongying257000China

Continental shale oil reservoirs,characterized by numerous bedding planes and micro-nano scale pores,feature significantly higher stress sensitivity compared to other types of ***,research on suitable stress sensitivity characterization models is still *** this study,three commonly used stress sensitivity models for shale oil reservoirs were considered,and experiments on representative core samples were *** fitting and comparing the data,the“exponential model”was identified as a characterization model that accurately represents stress sensitivity in continental shale oil *** validate the accuracy of the model,a two-phase seepage mathematical model for shale oil reservoirs coupled with the exponential model was *** model was discretely solved using the finite volume method,and its accuracy was verified through the commercial simulator *** study evaluated the productivity of a typical horizontal well under different engineering,geological,and fracture *** results indicate that considering stress sensitivity leads to a 13.57%reduction in production for the same matrix ***,as the fracture half-length and the number of fractures increase,and the bottomhole flowing pressure decreases,the reservoir stress sensitivity becomes higher.

关键词： Shale oil horizontal wells Embedded Discrete Fracture Model(EDFM) stress sensitivity numerical simulation sensitivity analysis

Progress on the antiferromagnetic topological insulator MnBi2Te4

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National Science Review 2024年第2期11卷 33-49页

作者： Shuai Li Tianyu Liu chang Liu Yayu Wang Hai-Zhou lu X.C.Xie Department of Physics Harbin Institute of Technology Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen Key Laboratory of Quantum Science and Engineering International Quantum Academy Beijing Academy of Quantum Information Sciences Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of Physics Renmin University of China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua University Frontier Science Center for Quantum Information Hefei National Laboratory International Center for Quantum Materials School of Physics Peking University Institute for Nanoelectronic Devices and Quantum Computing Fudan University

Topological materials, which feature robust surface and/or edge states, have now been a research focus in condensed maTher physics. They represent a new class of materials exhibiting nontrivial topological phases,and provide a platform for exploring exotic transport phenomena, such as the quantum anomalous Hall effect and the quantum spin Hall effect. Recently, magnetic topological materials have attracted considerable interests due to the possibility to study the interplay between topological and magnetic *** particular, the quantum anomalous Hall and axion insulator phases can be realized in topological insulators with magnetic order. MnBi2Te4, as the first intrinsic antiferromagnetic topological insulator discovered, allows the examination of existing theoretical predictions; it has been extensively studied, and many new discoveries have been made. Here we review the progress made on MnBi2Te4from both experimental and theoretical aspects. The bulk crystal and magnetic structures are surveyed first, followed by a review of theoretical calculations and experimental probes on the band structure and surface states, and a discussion of various exotic phases that can be realized in MnBi2Te4. The properties of MnBi2Te4thin films and the corresponding transport studies are then reviewed, with an emphasis on the edge state transport. Possible future research directions in this field are also discussed.

关键词： MnBi2Te4 magnetic topological insulator antiferromagnetic quantum anomalous Hall effect axion insulator

Linking Perceived Risk of Public Health Emergency to Psychological Distress among Chinese College Students: The Chain Mediation Role of Balanced Time Perspective and Negative Coping Styles

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International Journal of Mental Health Promotion 2024年第8期26卷 599-610页

作者： Biru chang Shengqiang Zhu qian Xie Yanghui Dai School of Education Science Nanjing Normal UniversityNanjing210024China Center of Clinical Psychology The Third People’s Hospital of Heze CityHeze274031China School of Education Science Northwest Normal UniversityLanzhou730070China Mental Health Center Hubei Polytechnic UniversityHuangshi435003China College of Teacher Education Zhejiang Normal UniversityJinhua321004China

Background:With public health emergencies(PHE)worldwide increasing,the perceived risk of PHE has been one of the critical factors influencing college students’psychological ***,the mechanisms by which the perceived risk of PHE affects college students’psychological distress are not *** study’s purpose was to investigate the mediation roles of deviation from a balanced time perspective(DBTP)and negative coping styles between the perceived risk of PHE and psychological ***:A convenience sampling method was used to survey 1054 Chinese college students with *** was collected using the Public Risk Perception Scale(PRPS),the Zimbardo Time Perspective Inventory(ZTPI),the Simplified Coping Style Questionnaire(SCSQ),the PHE Anxiety Scale,and the Chinese version of the Patient Health Questionnaire(PHQ).The associations between the perceived risk of PHE,DBTP,negative coping styles,and psychological distress were clarified using the correlation ***,the mediating roles of DBTP and negative coping styles between the perceived risk of PHE and psychological distress were investigated using a structural equation ***:The findings revealed low to moderate correlations between the variables ***’perceived risk of PHE was a positive predictor of their psychological distress(b=0.219,plusion:These findings showed how the perceived risk of PHE affected college students’psychological ***,these results suggested that improving students’mental ability to switch effectively among different time perspectives depending on task features and situational considerations and reducing their negative coping styles might be effective ways to pro

关键词： Perceived risk of public health emergency balanced time perspective negative coping styles psychological distress college students China