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Cucurbit[n]uril-based nanostructure construction and modification

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Chinese Chemical Letters 2024年第8期35卷 138-148页

作者： Lijun mao Shuo Li Xin Zhang Zhan-Ting Li Da Ma School of Pharmaceutical Engineering&Institute for Advanced Studies Taizhou UniversityJiaojiang 318000China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China

New fabrication method of nanostructures is of great importance for the applications of nanoscience and *** review summarizes cucurbit[n]uril(CB[n])-based nanostructure fabrication and modification *** strategies include the use of CB[n]s as building blocks and supramolecular crosslinkers to fabricate nanostructures,to surface modify nanostructures,and as gatekeepers to control the release of encapsulated *** nanostructures are used for drug delivery,bioimaging,chemical sensing,catalysis and other ***[n]s often play a vital role in the fabrication of these nanos-tructures,and the realization of the applications.

关键词： Cucurbit[n]uril Nanostructure Host-guest interaction Nanofabrication

Tree mycorrhizal associations determine how biodiversity,large trees,and environmental factors drive aboveground carbon stock in temperate forests

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Forest Ecosystems 2024年第4期11卷 448-456页

作者： Yue Chen Zikun mao Jonathan A.Myers Jinghua Yu Xugao Wang CAS Key Laboratory of Forest Ecology and Silviculture Institute of Applied EcologyChinese Academy of SciencesShenyang110016China University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Terrestrial Ecosystem Carbon Neutrality Shenyang110016China Department of Biology Washington University in St.LouisSt.LouisMissouriUSA

Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon ***,recent studies in temperate forests suggest that the relative importance of these factors depends on tree mycorrhizal associations,whereby large-tree effects may be driven by ectomycorrhizal(EM)trees,diversity effects may be driven by arbuscular mycorrhizal(AM)trees,and environment effects may depend on differential climate and soil preferences of AM and EM *** test this hypothesis,we used forest-inventory data consisting of over 80,000 trees from 631 temperate-forest plots(30 m×30 m)across Northeast China to examine how biodiversity(species diversity and ecological uniqueness),large trees(top 1%of tree diameters),and environmental factors(climate and soil nutrients)differently regulate aboveground carbon stocks of AM trees,EM trees,and AM and EM trees combined(*** aboveground carbon stock).We found that large trees had a positive effect on both AM and EM tree carbon ***,biodiversity and environmental factors had opposite effects on AM *** tree carbon ***,the two components of biodiversity had positive effects on AM tree carbon stocks,but negative effects on EM tree carbon *** heterogeneity(mean annual temperature and soil nutrients)also exhibited contrasting effects on AM and EM tree carbon ***,for the total carbon stock,the positive large-tree effect far surpasses the diversity and environment *** is mainly because when integrating AM and EM tree carbon stock into total carbon stock,the opposite diversity-effect(also environment-effect)on AM *** tree carbon stock counteracts each other while the consistent positive large-tree effect on AM and EM tree carbon stock is *** summary,this study emphasized a mycorrhizal viewpoint to better understand the determinants of overarching aboveground carbon profile across regional forests.

关键词： Biodiversity Ecological uniqueness Environment heterogeneity Large trees Mycorrhizal associations Tree carbon stock

Gradient Estimate for an Exponentially Harmonic Type Heat Equation on Riemannian Manifolds

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Journal of Mathematical Research with Applications 2024年第4期44卷 495-501页

作者： Jianyi mao Xinrong JIANG School of Mathematics and Statistics Jiangxi Normal University

In this paper, we derive a Hamilton-Souplet-Zhang type gradient estimate for exponentially harmonic type heat equation on Riemannian manifolds. As its application, we obtain a Liouville type theorem.

关键词： Gradient estimate exponentially harmonic type heat equation Riemannian manifold Liouville theorem

Lightweight and high-security laser-based cotton tip pruning robot

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 98-108页

作者： Xuan'ang Guo Ziyang mao Zedong Shi Wei Lu School of Artificial Intelligence Nanjing Agricultural UniversityNanjing 210031China

Considering the current environmental pollution caused by chemical topping,plant damage caused by mechanical topping,and the high cost of manual topping,a laser-based cotton-tip pruning robot for field cotton was designed in this *** main advantages of this robot include its safety,light weight,low cost,and environmental ***,the structural design,measurement,and corresponding control system design of the robot were ***,a precise laser control method based on Yolov5 cotton top identification and the inverse kinematic solution of parallel robot rapid positioning were ***,the optimal laser irradiation wavelength and duration were ***,a laser-topping experiment was conducted,and the overall accuracy and recall rates for cotton identification were 98.3%and 99.3%,*** AP and mAP at the threshold value of 0.5 reached 99.3%and 78.8%,*** maximum positioning error of the jacking system is 2.6 mm,and the repeated positioning error is within±1.2 cm,which meets the accuracy requirements of laser ***-purple laser irradiation at 15 W and 405 nm for 22 s was the best topping *** the effects of cotton topping with and without manual topping,it can be seen that laser topping significantly improved the yield and *** with the photothermal response of the cotton topping,the feasibility of laser topping was verified both theoretically and *** laser-topping scheme proposed in this study exhibits high efficiency,environmental protection,and safety,as well as good application prospects.

关键词： laser topping parallel manipulator photothermal response object detection

The influences of perforating phase and bedding planes on the fracture deflection in laminated shale

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Petroleum Science 2024年第2期21卷 1221-1230页

作者： Ming-Zhe Gu mao Sheng Xiao-Ying Zhuang Xin-Yi Li Gen-Sheng Li National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China College of Petroleum Engineering China University of PetroleumBeijing102249China College of Civil Engineering Tongji UniversityShanghai200092China

The perforating phase leads to complex and diverse hydraulic fracture propagation behaviors in laminated shale formations. In this paper, a 2D high-speed imaging scheme which can capture the interaction between perforating phase and natural shale bedding planes was proposed. The phase field method was used to simulate the same conditions as in the experiment for verification and hydraulic fracture propagation mechanism under the competition of perforating phase and bedding planes was *** results indicate that the bedding planes appear to be no influence on fracture propagation while the perforating phase is perpendicular to the bedding planes, and the fracture propagates along the perforating phase without deflection. When the perforating phase algins with the bedding planes, the fracture initiation pressure reserves the lowest value, and no deflection occurs during fracture propagation. When the perforating phase is the angle 45°, 60°and 75°of bedding planes, the bedding planes begin to play a key role on the fracture deflection. The maximum deflection degree is reached at the perforating phase of75°. Numerical simulation provides evidence that the existence of shale bedding planes is not exactly equivalent to anisotropy for fracture propagation and the difference of mechanical properties between different shale layers is the fundamental reason for fracture deflection. The findings help to understand the intrinsic characteristics of shale and provide a theoretical basis for the optimization design of field perforation parameters.

关键词： Shale Propagation Perforating Bedding Structure

Characterizing structure of cross-disciplinary impact of global disciplines:A perspective of the Hierarchy of Science

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Journal of Data and Information Science 2024年第1期9卷 53-81页

作者： Ruolan Liu Jin mao Gang Li Yujie Cao Center for Studies of Information Resources Wuhan UniversityWuhan 430072China School of Information Management Wuhan UniversityWuhan 430072China School of Information Management Central China Normal University 430072WuhanChina

Purpose:Interdisciplinary fields have become the driving force of modern science and a significant source of scientific ***,there is still a paucity of analysis about the essential characteristics of disciplines’cross-disciplinary ***/methodology/approach:In this study,we define cross-disciplinary impact on one discipline as its impact to other disciplines,and refer to a three-dimensional framework of variety-balance-disparity to characterize the structure of cross-disciplinary *** variety of cross-disciplinary impact of the discipline was defined as the proportion of the high cross-disciplinary impact publications,and the balance and disparity of cross-disciplinary impact were measured as *** demonstrate the cross-disciplinary impact of the disciplines in science,we chose Microsoft Academic Graph(MAG)as the data source,and investigated the relationship between disciplines’cross-disciplinary impact and their positions in the Hierarchy of Science(HOS).Findings:Analytical results show that there is a significant correlation between the ranking of cross-disciplinary impact and the HOS structure,and that the discipline exerts a greater cross-disciplinary impact on its neighboring *** bibliometric features that measure the hardness of a discipline,including the number of references,the number of cited disciplines,the citation distribution,and the Price index have a significant positive effect on the variety of cross-disciplinary *** number of references,the number of cited disciplines,and the citation distribution have significant positive and negative effects on balance and disparity,*** is concluded that the less hard the discipline,the greater the cross-disciplinary impact,the higher balance and the lower disparity of cross-disciplinary *** limitations:In the empirical analysis of HOS,we only included five broad *** study also has some biases caused by the data source and a

关键词： Interdisciplinary research cross-disciplinary Scientific impact Soft science Hard science Citation

Attention-Enhanced Voice Portrait Model Using Generative Adversarial Network

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Computers, Materials & Continua 2024年第4期79卷 837-855页

作者： Jingyi mao Yuchen Zhou YifanWang Junyu Li Ziqing Liu Fanliang Bu School of Information Network Security People’s Public Security University of ChinaBeijing100038China

Voice portrait technology has explored and established the relationship between speakers’ voices and their facialfeatures, aiming to generate corresponding facial characteristics by providing the voice of an unknown *** to its powerful advantages in image generation, Generative Adversarial Networks (GANs) have now beenwidely applied across various fields. The existing Voice2Face methods for voice portraits are primarily based onGANs trained on voice-face paired datasets. However, voice portrait models solely constructed on GANs facelimitations in image generation quality and struggle to maintain facial similarity. Additionally, the training processis relatively unstable, thereby affecting the overall generative performance of the model. To overcome the abovechallenges,wepropose a novel deepGenerativeAdversarialNetworkmodel for audio-visual synthesis, namedAVPGAN(Attention-enhanced Voice Portrait Model using Generative Adversarial Network). This model is based ona convolutional attention mechanism and is capable of generating corresponding facial images from the voice ofan unknown speaker. Firstly, to address the issue of training instability, we integrate convolutional neural networkswith deep GANs. In the network architecture, we apply spectral normalization to constrain the variation of thediscriminator, preventing issues such as mode collapse. Secondly, to enhance the model’s ability to extract relevantfeatures between the two modalities, we propose a voice portrait model based on convolutional attention. Thismodel learns the mapping relationship between voice and facial features in a common space from both channeland spatial dimensions independently. Thirdly, to enhance the quality of generated faces, we have incorporated adegradation removal module and utilized pretrained facial GANs as facial priors to repair and enhance the clarityof the generated facial images. Experimental results demonstrate that our AVP-GAN achieved a cosine similarity of0.511, ou

关键词： Cross-modal generation GANs voice portrait technology face synthesis

A chitosan-based antibacterial hydrogel with injectable and self-healing capabilities

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Marine Life Science & Technology 2024年第1期6卷 115-125页

作者： Rui Chen Yanan Hao Secundo Francesco Xiangzhao mao Wen-Can Huang State Key Laboratory of Marine Food Processing and Safety Control College of Food Science and EngineeringOcean University of ChinaQingdao 266404China Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology Qingdao 266237China Qingdao Key Laboratory of Food Biotechnology Qingdao 266404China Key Laboratory of Biological Processing of Aquatic Products China National Light IndustryQingdao 266404China Istituto di Scienze e Tecnologie Chimiche“Giulio Natta” Consiglio Nazionale delle Ricerche via Mario Bianco 920131 MilanItaly

The presence of bacteria directly affects wound ***-based hydrogel biomaterials are a solution as they offer advantages for wound-healing applications due to their strong antimicrobial ***,a double-cross-linking chitosanbased hydrogel with antibacterial,self-healing,and injectable properties is *** chitosan was successfully prepared,and the thiolated chitosan molecules were cross-linked by Ag-S coordination to form a supramolecular ***,the amine groups in the thiolated chitosan covalently cross-linked with genipin to further promote hydrogel *** vitro experimental results indicate that hydrogel can release Ag^(+)over an extended time,achieving an antibacterial rate of over 99% against Escherichia coli and Staphylococcus *** to the reversible and dynamic feature of Ag-S coordination,an antibacterial hydrogel exhibited injectable and self-healing ***,the hydrogel showed excellent biocompatibility and biodegradability.

关键词： Hydrogel Chitosan Silver ion Cross-linking Antibacterial

Construct a 3D microsphere of HMX/B/Al/PTFE to obtain the high energy and combustion reactivity

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Defence Technology（防务技术） 2024年第2期32卷 45-54页

作者： Jian Wang Jie Chen Yaofeng mao Yongjun Deng Wei Cao Fude Nie Jun Wang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621999PR China Shock and Vibration of Engineering Materials and Structures Key Lab of Sichuan Province Mianyang 621010PR China

Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy ***,the low combustion efficiency and reactivity of metal fuels,especially boron(B),severely limit their practical ***,multi-component 3D microspheres of HMX/B/Al/PTFE(HBA)have been designed and successfully prepared by emulsion and solvent evaporation method to achieve superior energy and combustion *** reactivity and energy output of HBA are systematically measured by ignitionburning test,constant-volume explosion vessel system and bomb *** to the increased interfacial contact and reaction area,HBA shows higher flame propagation rate,faster pressurization rate and larger combustion heat of 29.95 cm/s,1077 kPa/s,and 6164.43 J/g,which is 1.5 times,3.5 times,and 1.03 times of the physical mixed counterpart(HBA-P).Meanwhile,HBA also shows enhanced energy output and reactivity than 3D microspheres of HMX/B/PTFE(HB)resulting from the high reactivity of *** reaction mechanism of 3D microspheres is comprehensively investigated through combustion emission spectral and thermal analysis(TG-DSC-MS).The superior reactivity and energy of HBA originate from the surface etching of fluorine to the inert shell(Al_(2)O_(3) and B_(2)O_(3))and the initiation effect of Al to *** work offers a promising approach to design and prepare high-performance energetic materials for the practical applications.

关键词： HMX/B/Al/PTFE 3D microspheres Surface etching Reaction mechanism