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Drainage of paddy terraces impacts structures and soil properties in the globally important agricultural heritage of Hani Paddy Terraces,China

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International Soil and Water Conservation Research 2024年第1期12卷 64-76页

作者： ming Wang li Rong Yanbo li Jiangcheng Huang Yuanmei Jiao Xiaoyan Wei Institute of International Rivers and Eco-Security Kunming650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security Kunming650500China Power China Kunming Engineering Corporation limited Kunming650051China Department of Geography Yunnan Normal UniversityKunming650500China Yunnan Provincial Archives of Surveying and Mapping(Yunnan Provincial Geomatics Centre) Kunming650032China

Marginalization and abandonment of paddy terraces are widespread,but their effects on the sustainability of subsequent agricultural production are still *** Paddy Terraces,included in Globally Important Agriculture Heritage Systems,are threatened by paddy fields ***,changes in terrace structure,the productivity of topsoil(0-20 cm),and soil water holding capacity at 0-70 cm depth were determined in a case study of Hani Paddy Terraces in Amengkong River Basin in Yuanyang County in Southwestern China,which had been converted into dryland terraces for 2-14 *** results showed that:(1)The degree of terrace structures degradation exhibited a U-shaped curve with increasing time since draining,with those drained for 5-9 years having the best structure;(2)Soil productivity index decreased first and then increased with time after conversion;(3)Maximum water holding capacity at 0-70 cm soil depth dramatically decreased after conversion and such trend became increasingly obvious with increasing time since *** study revealed that drainage of paddy terraces along with associated changes in crop and field management led to an increase in soil productivity,but degradation of terrace structures and a decrease in water holding capacity will inhibit restoration to paddy *** findings enhance the understanding of the biophysical changes due to marginalization in paddy terraces.

关键词： Hani paddy terraces Terraces marginalization Terrace structure degradation Soil productivity Water holding capacity

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Autonomous multi-drone racing method based on deep reinforcement learning

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Science China(Information Sciences) 2024年第8期67卷 35-48页

作者： Yu KANG Jian DI ming li Yunbo ZHAO Yuhui WANG Department of Automation University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Racing drones have attracted increasing attention due to their remarkable high speed and excellent maneuverability. However, autonomous multi-drone racing is quite difficult since it requires quick and agile flight in intricate surroundings and rich drone interaction. To address these issues, we propose a novel autonomous multi-drone racing method based on deep reinforcement learning. A new set of reward functions is proposed to make racing drones learn the racing skills of human experts. Unlike previous methods that required global information about tracks and track boundary constraints, the proposed method requires only limited localized track information within the range of its own onboard sensors. Further, the dynamic response characteristics of racing drones are incorporated into the training environment, so that the proposed method is more in line with the requirements of real drone racing scenarios. In addition, our method has a low computational cost and can meet the requirements of real-time racing. Finally, the effectiveness and superiority of the proposed method are verified by extensive comparison with the state-of-the-art methods in a series of simulations and real-world experiments.

关键词： autonomous multi-drone racing deep reinforcement learning Markov game racing drone sim-to-real

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Design of new chemicals for advanced electrolytes

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Science China Chemistry 2024年第5期67卷 1378-1380页

作者： Haoran Cheng Zheng Ma Qian li jun ming State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China University of Science and Technology of China Hefei 230026China

This highlight is inspired by a recent article in Nature Energy in which liu and co-workers [1] from Tsinghua University designed a new asymmetric lithium salt (i.e., lithium 1,1,1-trifluoro-N-[2-[2-(2-methoxy ethoxy)ethoxy]ethyl] methanesulfonamide (li FEA)) and applied it as a new lithium-salt additive in the conventional carbonate-based electrolyte,overcoming the incompatibility issue of carbonate electrolytes with lithium metal in lithium metal batteries (LMBs),even achieving a fast-charging feature.

关键词： lithium carbonate electrolyte

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An overview of autophagy in the differentiation of dental stem cells

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BIOCELL 2024年第1期48卷 47-64页

作者： XITONG ZHAO TIANjuAN ju XINWEI li CHANGFENG liU LULU WANG li-AN WU State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Clinical Research Center for Oral DiseasesDepartment of Pediatric DentistrySchool of StomatologyThe Fourth Military Medical UniversityXi’an710032China

Dental stem cells(DSCs)have attracted significant interest as autologous stem cells since they are easily accessible and give a minimal immune *** properties and their ability to both maintain self-renewal and undergo multi-lineage differentiation establish them as key players in regenerative *** many regulatory factors determine the differentiation trajectory of DSCs,prior research has predominantly been based on genetic,epigenetic,and molecular *** evidence suggests that DSC differentiation can also be influenced by autophagy,a highly conserved cellular process responsible for maintaining cellular and tissue homeostasis under various stress *** comprehensive review endeavors to elucidate the intricate regulatory mechanism and relationship between autophagy and DSC *** achieve this goal,we dissect the intricacies of autophagy and its ***,we elucidate its pivotal roles in impacting DSC differentiation,including osteo/odontogenic,neurogenic,and angiogenic ***,we reveal the regulatory factors that govern autophagy in DSC lineage commitment,including scaffold materials,pharmaceutical cues,and the extrinsic *** implications of this review are far-reaching,underpinning the potential to wield autophagy as a regulatory tool to expedite DSC-directed differentiation and thereby promote the application of DSCs within the realm of regenerative medicine.

关键词： Dental stem cells Cell differentiation Autophagy Mitophagy Autophagy regulation

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Whole-process case management effects on mental state and selfcare ability in patients with liver cancer

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 833-841页

作者： Man-Di ju Qin Qin Meng li Department of Internal Medicine of Abdominal Oncology Hubei Cancer HospitalWuhan 430070Hubei ProvinceChina Department of Hepatological Surgery Wuhan No.1 HospitalWuhan 430000Hubei ProvinceChina Department of Nursing General Hospital of the Yangtze River ShippingWuhan 430014Hubei ProvinceChina

BACKGROUND Regarding the incidence of malignant tumors in China,the incidence of liver cancer ranks fourth,second only to lung,gastric,and esophageal *** case fatality rate ranks third after lung and cervical *** a previous study,the whole-process management model was applied to patients with breast cancer,which effectively reduced their negative emotions and improved treatment adherence and nursing *** In this single-center,randomized,controlled study,60 randomly selected patients with liver cancer who had been admitted to our hospital from January 2021 to January 2022 were randomly divided into an observation group(n=30),who received whole-process case management on the basis of routine nursing mea-sures,and a control group(n=30),who were given routine nursing *** compared differences between the two groups in terms of anxiety,depression,the level of hope,self-care ability,symptom distress,sleep quality,and quality of *** Post-intervention,Hamilton anxiety scale,Hamilton depression scale,memory symptom assessment scale,and Pittsburgh sleep quality index scores in both groups were lower than those pre-intervention,and the observation group had lower scores than the control group(Plity assessment scale-revision in Chinese,and quality of life measurement scale for patients with liver cancer scores in both groups were higher than those pre-intervention,with higher scores in the observation group compared with the control group(Pliver cancer,alleviate symptoms and problems,and improve the level of hope,self-care ability,sleep quality,and quality of life,as well as provide feasible nursing alternatives for patients with liver cancer.

关键词： liver cancer Mental state Self-care ability Whole-process case management life quality Nursing

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On traceable iterated line graph and hamiltonian path index

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 239-252页

作者： NIU Zhao-hong XIONG li-ming YANG Wei-hua School of Mathematical Sciences Shanxi UniversityTaiyuan 030006China School of Mathematics and Statistics Beijing Key Laboratory on MCAACIBeijing Institute of TechnologyBeijing 100081China Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

Xiong and liu[21]gave a characterization of the graphs G for which the n-iterated line graph L^(n)(G)is hamiltonian,for n≥*** this paper,we study the existence of a hamiltonian path in L^(n)(G),and give a characterization of G for which L^(n)(G)has a hamiltonian *** applications,we use this characterization to give several upper bounds on the hamiltonian path index of a graph.

关键词： iterated line graph traceable hamiltonian index hamiltonian path index

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Analysis of application range of simplified models for field to thermo-field to thermionic emission processes from the cathode

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Plasma Science and Technology 2024年第9期26卷 51-60页

作者： li SUN Zhuo DAI ming XU Wei WANG Zengyao li Applied Physics Department Xi’an University of TechnologyXi’an 710048People’s Republic of China Key Laboratory of Thermo-Fluid Science and Engineering Ministry of EducationSchool of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049People’s Republic of China

Electron emission plays a dominant role in plasma-cathode interactions and is a key factor in many plasma phenomena and industrial *** is necessary to illustrate the various electron emission mechanisms and the corresponding applicable description models to evaluate their impacts on discharge *** this study,detailed expressions of the simplified formulas valid for field emission to thermo-field emission to thermionic emission typically used in the numerical simulation are proposed,and the corresponding application ranges are determined in the framework of the Murphy-Good theory,which is commonly regarded as the general model and to be accurate in the full range of conditions of the validity of the *** parameterization was used to evaluate the emission current density of the Murphy-Good formula,and a deviation factor was defined to obtain the application ranges for different work functions(2.5‒5 eV),cathode temperatures(300‒6000 K),and emitted electric fields(10^(5) to 10^(10) V·m^(-1)).The deviation factor was shown to be a nonmonotonic function of the three parameters.A comparative study of particle number densities in atmospheric gas discharge with a tungsten cathode was performed based on the one-dimensional implicit particle-in-cell(PIC)with the Monte Carlo collision(MCC)method according to the aforementioned application *** was found that small differences in emission current density can lead to variations in the distributions of particle number density due to changes in the collisional *** study provides a theoretical basis for selecting emission models for subsequent numerical simulations.

关键词： electron emission processes application range Murphy-Good theory implicit particlein-cell Monte Carlo collision method

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A review of MXene-derived quantum dots:Synthesis,characterization,properties,and applications

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Particuology 2024年第8期91卷 50-71页

作者： Chunhe Zhou Kar Ban Tan Wenjuan Han li Wang ming Lu The Joint Laboratory of MXene Materials Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of EducationJilin Normal UniversityChangchunJilin 130103China Department of Chemistry Faculty of ScienceUniversiti Putra MalaysiaSerdangSelangor 43400Malaysia

Cutting MXene to a minimum size and forming the derived two-dimensional MXene quantum dots(MQDs),which possess a unique intrinsic layered geometry structure,restricts exciton due to their novel spatial *** gives rise to a broad spectrum of fascinating properties,rendering them for various ***,the correlation between composition,structure,and processing control of MQDs is investigated systematically,giving further insight into the intrinsic and extrinsic *** review also provides an opportunity to explore new compositions,modify the properties,and tailor MQDs into the guided architectural design before any prospective applications.

关键词： MXene Quantum dots Characterization Properties Applications

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Novel process for facile preparation of mesoporous silica-based materials with controllable pore structure from coal fly ash Author links open overlay panel

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Particuology 2024年第8期91卷 128-137页

作者： Jian-ming Gao Zhen li Shujia Ma Yuanyuan Zhang Fangqin Cheng Institute of Resources and Environment Engineering State Environmental Protection Key Laboratory of Efficient Utilization Technology of Coal Waste ResourcesShanxi Collaborative Innovation Center of High Value-added Utilization of Coal-related WastesShanxi UniversityTaiyuan 030006China

Extraction of silica from fly ash to produce mesoporous silica materials is one of the most important utilization *** silica could not be synthesized on a large-scale by conventional sol-gel *** this paper,facile preparation of mesoporous silica with controllable pore structure from fly ash by the template-free process via two steps of mineral phase transformation and selective acid etching was *** influence of crystalline structure and acid etching degree on structure of as-synthesized mesoporous silica materials was revealed,as well as mechanism of crystalline structure transformation and pore structure *** results show that mullite and quartz could be transformed into acid-soluble kaliophilite when fly ash reacted with K_(2)CO_(3)at temperature of 800-1100℃.The hexagonal kaliophilite would be transformed into orthorhombic KAlSiO_(4)-O1 phase when the temperature is controlled at 1100℃.Mesoporous silica with specific surface area of 475.93 m^(2)/g and 642.57 m^(2)/g could be synthesized from activated fly ash with kaliophilite and KAlSiO_(4)-O1 phase crystalline *** controlling the degree of acid etching,mesoporous silica materials with different pore structures can be *** paper provides a cost-effective and large-scale process for the preparation of mesoporous silica materials with controllable pore structure from solid waste fly ash.

关键词： Fly ash Mesoporous silica Crystal transformation Acid etching Controllable pore structure

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Keplerate polyoxomolybdate nanoball mediated controllable preparation of metal-doped molybdenum disulfide for electrocatalytic hydrogen evolution in acidic and alkaline media

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Chinese Chemical Letters 2024年第7期35卷 524-528页

作者： Ping Wang Ting Wang ming Xu Ze Gao Hongyu li Bowen li Yuqi Wang Chaoqun Qu ming Feng Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun 130103China School of Science Changchun University of Science and TechnologyChangchun 130022China

Rationally designed novel cost-effective hydrogen evolution reaction(HER)electrocatalysts with controlled surface composition and advanced structural superiority is extremely critical to optimize the HER ***(POMs)with structural diversity and adjustable element compositions represent a promising precursor for rational design and preparation of HER ***,a series of transition metal-doped MoS_(2)materials with different surface engineered structures(Fe,Cr,V doping and S vacancies)(M-MoS_(2)/CC,M=Fe,Cr and V)were fabricated by a simple hydrothermalvulcanization strategy using Keplerate polyoxomolybdate nanoball({Mo_(72)Fe_(30)},{Mo_(72)Cr_(30)},{Mo_(72)V_(30)},{Mo_(132)})as *** enlarged interlayer spacing as well as the integration of homogeneous transition metal doping and abundant sulfur vacancies endows prepared M-MoS_(2)/CC with superior HER electrocatalytic performance and excellent long-term working stability in both acidic and alkaline *** optimized Fe-MoS_(2)/CC afford current densities of 10 and 50 mA/cm^(2)at overpotentials of 188/272 mV and 194/394 mV in 0.5 mol/L H_(2)SO_(4)and 1.0 mol/L KOH aqueous solution,respectively,outperforming most of reported typical transition metal sulfide-based *** work represents an important breakthrough for POMs-mediated highly efficient transition metal sulfide-based HER electrocatalysts with wide range pH activity and may provide new options for the rational design of promising HER electrocatalysts and beyond.

关键词： Polyoxometalate Electrocatalytic Hydrogen evolution reaction Doping MoS_(2)

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