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Energy & Environmental Materials 2024年第2期7卷 308-319页

作者： Guanghu He huang Luo Chuanfang Yan Yuting Wan Dang Wu Hang Luo Yuan Liu sheng Chen Key Laboratory of Polymeric Materials and Application Technology of Hunan Province College of ChemistryXiangtan UniversityXiangtan 411105China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Guangdong University of Petrochemical Technology Maoming 525000China

How to achieve synergistic improvement of permittivity(ε_(r))and breakdown strength(E_(b))is a huge challenge for polymer ***,for the first time,theπ-conjugated comonomer(MHT)can simultaneously promote theε_(r)and E_(b)of linear poly(methyl methacrylate)(PMMA)*** PMMA-based random copolymer films(P(MMA-co-MHT)),block copolymer films(PMMA-b-PMHT),and PMMA-based blend films were prepared to investigate the effects of sequential structure,phase separation structure,and modification method on dielectric and energy storage properties of PMMA-based dielectric *** a result,the random copolymer P(MMA-coMHT)can achieve a maximumε_(r)of 5.8 at 1 kHz owing to the enhanced orientation polarization and electron *** electron injection and charge transfer are limited by the strong electrostatic attraction ofπ-conjugated benzophenanthrene group analyzed by the density functional theory(DFT),the discharge energy density value of P(MMA-co-PMHT)containing 1 mol%MHT units with the efficiency of 80%reaches15.00 J cm^(-3)at 872 MV m^(-1),which is 165%higher than that of pure *** study provides a simple and effective way to fabricate the high performance of polymer dielectrics via copolymerization with the monomer of P-type semi-conductive polymer.

关键词： dielectric capacitor electrical properties energy density polymer dielectric semiconductor polymer

Micromechanism and mathematical model of stress sensitivity in tight reservoirs of binary granular medium

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Petroleum Science 2024年第3期21卷 1780-1795页

作者： Jian-Bang Wu sheng-Lai Yang Qiang Li Kun Yang Can huang Dao-Ping Lv Wei Zhou State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China Laboratoire de G eologie Ecole Normale Sup erieure/CNRS UMR8538PSL Research UniversityParis75005France Research Institute of Exploration and Development Xinjiang Oilfield CompanyKaramay834000XinjiangChina

Research on reservoir rock stress sensitivity has traditionally focused on unary granular structures,neglecting the binary nature of real reservoirs,especially tight *** the stresssensitive behavior and mathematical characterization of binary granular media remains a challenging *** this study,we conducted online-NMR experiments to investigate the permeability and porosity evolution as well as stress-sensitive control mechanisms in tight sandy conglomerate *** results revealed stress sensitivity coefficients between 0.042 and 0.098 and permeability damage rates ranging from 65.6%to 90.9%,with an average pore compression coefficient of 0.0168—0.0208 MPa ***-scale compression occurred in three stages:filling,compression,and compaction,with matrix pores playing a dominant role in pore *** stress sensitivity of binary granular media was found to be influenced by the support structure and particle *** stress sensitivity was associated with small fine particle size,high fines content,high uniformity coefficient of particle size,high plastic deformation,and low Young's ***-supported samples exhibited a high irreversible permeability damage rate(average=74.2%)and stress sensitivity coefficients(average=0.089),with pore spaces more *** contrast,grain-supported samples showed low stress sensitivity coefficients(average=0.021)at high stress *** on the experiments,we developed a mathematical model for stress sensitivity in binary granular media,considering binary granular properties and nested interactions using Hertz contact deformation and Poiseuille *** describing the change in activity content of fines under stress,we characterized the non-stationary state of compressive deformation in the binary granular structure and classified the reservoir into three *** model was applied for production prediction using actual data from the Mahu reservoir in China,showing that the e

关键词： Stress sensitivity Binary granular medium Tight reservoir Online-NMR Reservoir energy retention rate

A micro-crosslinked amphoteric hydrophobic association copolymer as high temperature-and salt-resistance fluid loss reducer for water-based drilling fluids

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Petroleum Science 2024年第3期21卷 1980-1991页

作者： Jian Li Yu-Xi Ji Xiao-Xiao Ni Kai-He Lv Xian-Bin huang Jin-sheng Sun School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Qingdao26650ShandongChina Inspection and Testing Center of Huabei Oil Field Company PetroChinaRenqiu062552HebeiChina Drilling Fluid Research Institute CNPC Engineering Technology R&D Company LimitedBeijing102206China

During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtration performance remains a ***,a micro-crosslinked amphoteric hydrophobic association copolymer(i.e.,DADC)was synthesized using N,N-dimethyl acrylamide,diallyl dimethyl ammonium chloride,2-acrylamido-2-methylpropane sulfonic acid,hydrophobic monomer,and pentaerythritol triallyl ether *** to the synergistic effects of hydrogen bonds,electrostatic interaction,hydrophobic association,and micro-crosslinking,the DADC copolymer exhibited outstanding temperature-and *** rheological experiments have shown that the DADC copolymer had excellent shear dilution performance and a certain degree of salt-responsive viscosity-increasing *** DADC copolymer could effectively adsorb on the surface of bentonite particles through electrostatic interaction and hydrogen bonds,which bring more negative charge to the bentonite,thus improving the hydration and dispersion of bentonite particles as well as the colloidal stability of the drilling ***,the drilling fluids constructed based on the DADC copolymer exhibited satisfactory rheological and filtration properties(FLHTHP=12 m L)after aging at high temperatures(up to200℃)and high salinity(saturated salt)***,this work provided new insights into designing and fabricating high-performance drilling fluid treatment agents,demonstrating good potential applications in deep and ultradeep drilling engineering.

关键词： Fluid loss reducer Temperature-and salt-resistance Hydrophobic association Amphoteric Micro-crosslinking

Transparent micropatterned conductive films based on highlyordered nanowire network

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Nano Research 2024年第5期17卷 4288-4297页

作者： Xin-Ran Zhang Hai-Tao Deng Xu Zeng Yi-Lin Wang Peng huang Xiao-sheng Zhang School of Integrated Circuit Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Transparent conductive films that are based on nanowire networks are essential to construct flexible,wearable,and even stretchable ***,large-scale precise micropatterning,especially with regard to the controllability of the organizing orientation of nanowires,is a critical ***,we proposed a liquid film rupture self-assembly approach for manufacturing transparent conductive films with microstructure arrays based on a highly ordered nanowire *** large-scale microstructure conductive films were fabricated through air-liquid interface self-assembly and liquid film rupture *** typical micropattern morphologies,including square,hexagon,circle,serpentine,etc.,were prepared to reveal the universal applicability of the proposed *** homogeneity and controllability of this approach were verified for multiple *** the assembly cycles increasing,the optical transmittance decreases *** addition,theoretical model analysis is carried out,and the analytical formula of the speed of the film moving with the surface tension and the density of the liquid film is ***,the feasibility of this approach for piezoresistive strain sensors is *** fabrication approach demonstrated a cost-effective and efficient method for precisely arranging nanowires,which is useful in transparent and wearable applications.

关键词： flexible electronics transparent conductive network micropatterning nanowires micro electromechanical systems(MEMS)

Recent advances in g-C_(3)N_(4)-based direct Z-scheme photocatalysts for environmental and energy applications

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Chinese Journal of Structural Chemistry 2024年第2期43卷 66-84页

作者： Xiaoming Fu Haibo huang Guogang Tang Jingmin Zhang Junyue sheng Hua Tang School of Intelligent Engineering and Technology Jiangsu Vocational College of Finance&EconomicsHuai'anJiangsu223003PR China School of Modem Equipment Manufacturing Changzhou Institute of Light Industry Technology ChangzhouJiangsu213164PR China School of Environmental Science and Engineering Qingdao UniversityQingdao266071PR China School of Materials Science and Engineering Hainan UniversityHaikou570228PR China

In the midst of the rapid advancement of photocatalysis,direct Z-scheme heterojunction photocatalysts have emerged as a powerful solution to address environmental challenges and the looming energy *** precise engineering of direct Z-scheme heterojunction photocatalysts proves highly beneficial in optimizing their elec-tronic structure,ultimately enhancing their photocatalytic ***,graphitic carbon nitride(g-C_(3)N_(4))has recently gained recognition as a leading candidate for the creation of direct Z-scheme heterojunctions,owing to its favorable attributes such as a moderate band-gap(2.7 eV),high reduction potential and abundant active *** this review,we offer a concise overview of the fundamental principles and recent advancements in g-C_(3)N_(4)-based direct Z-scheme photocatalytic ***,we delve into the various practical applica-tions of g-C_(3)N_(4)-based direct Z-scheme photocatalysts,specifically in the realms of energy conversion and envi-ronmental *** applications include the removal of contaminant pollutants through photocatalytic degradation,water splitting(comprising H_(2)-generation,O_(2)-evolution,and overall water splitting),and CO_(2)***,we present comprehensive characterization methods and strategies aimed at further enhancing the photocatalytic activity of g-C_(3)N_(4)-based direct Z-scheme photocatalytic *** conclude,this review offers summarizing insights and a brief discussion on future challenges and prospects pertaining to g-C_(3)N_(4)-based direct Z-scheme *** believe that this review will inspire continued exploration and foster a deeper understanding of the groundbreaking possibilities within photocatalytic *** also provides valuable guidance for the design and construction of innovative direct Z-scheme photocatalysts.

关键词： Carbon nitride Photocatalyst Z-scheme systems Environmental remediation Energy conversion

Stress sensitivity analysis for a wide-chord fan blade using an adjoint method

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Chinese Journal of Aeronautics 2024年第10期37卷 103-117页

作者： Han YANG Shoujia GONG Yi LI Junxing TANG Dingxi WANG sheng huang Shenren XU School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China

High-performance compressor design is best achieved with a good trade-off between aerodynamic and structural considerations,which requires efficient and accurate multidisciplinary design and optimization *** advanced compressors are defined with a large design space,their optimization is most efficiently achieved using a gradient-based approach,where the gradient can be computed using an adjoint method,at a cost nearly independent of the dimension of the design *** the adjoint method has been widely used for aerodynamic shape optimization,its use for structural shape optimizations of compressor blades has not been as well *** paper discussed a discrete adjoint solver for structural sensitivity analysis developed within the opensource Computational Structural Mechanics(CSM)software CalculiX,and proposed an efficient stress sensitivity analysis method based on the Finite Element Method(FEM)using *** proposed method is applied to compute the stress sensitivity of a wide-chord fan blade in a highbypass-ratio *** accuracy of the adjoint-based stress sensitivity is verified against central finite *** terms of computational efficiency,the adjoint approach is about 4.5 times more efficient than the conventional approach using finite *** works marks an important step towards fluid-structural coupled adjoint optimization of wide-chord fan blades.

关键词： Adjoint method Multidisciplinary optimization Stress sensitivity analysis Finite element method Shape optimization

Identification and characterization of camptothecin tailoring enzymes in Nothapodytes tomentosa

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Journal of Integrative Plant Biology 2024年第6期66卷 1158-1169页

作者： Yin Chen Jian-Ping huang Yong-Jiang Wang Meng-Ling Tu Junheng Li Bingyan Xu Guoqing Peng Jing Yang sheng-Xiong huang State Key Laboratory of Phytochemistry and Plant Resources in West China and Yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor *** that two C-10 modified camptothecin derivatives,topotecan and irinotecan,have been approved as potent anticancer agents,there is a critical need for methods to access other aromatic ringfunctionalized congeners(e.g.,C-9,C-10,etc.).However,contemporary methods for chemical oxidation are generally harsh and low-yielding when applied to the camptothecin scaffold,thereby limiting the development of modified *** herein,we have identified four tailoring enzymes responsible for C-9 modifications of camptothecin from Nothapodytes tomentosa,via metabolomic and transcriptomic *** consist of a cytochrome P450(Nt CPT9H)which catalyzes the regioselective oxidation of camptothecin to 9-hydroxycamptothecin,as well as two methyltransferases(Nt OMT1/2,converting 9-hydroxycamptothecin to 9-methoxycamptothecin),and a uridine diphosphate-glycosyltransferase(Nt UGT5,decorating 9-hydroxycamptothecin to9-β-D-glucosyloxycamptothecin).Importantly,the critical residues that contribute to the specific catalytic activity of Nt CPT9H have been elucidated through molecular docking and mutagenesis *** work provides a genetic basis for producing camptothecin derivatives through metabolic *** will hasten the discovery of novel C-9 modified camptothecin derivatives,with profound implications for pharmaceutical manufacture.

关键词： camptothecin biosynthesis enzymatic assay Nothapodytes tomentosa tailoring enzyme transcriptomic analysis

Universal and efficient hybrid modeling and direct slicing method for additive manufacturing processes

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Advances in Manufacturing 2024年第2期12卷 300-316页

作者： Sen-Lin Wang Li-Chao Zhang Chao Cai Ming-Kai Tang Si Chen Jiang huang Yu-sheng Shi State Key Laboratory of Materials Processing and Die and Mould Technology Huazhong University of Science and TechnologyWuhan430074People’s Republic of China School of Machinery and Automation Wuhan University of Science and TechnologyWuhan430081People’s Republic of China

Model design and slicing contour generation in additive manufacturing(AM)data processing face challenges in terms of efficiency and scalability when stereolithography files generated by complex functionally graded structures have millions of *** paper proposes a hybrid modeling and direct slicing method for AM to efficiently construct and handle complex three-dimensional(3D)*** 3D solids,including conformal multigradient structures,were uniformly described using a small amount of data via signed distance *** hybrid representations were quickly discretized into numerous disordered directed lines using an improved marching squares *** establishing a directional HashMap to construct the topological relationship between lines,a connecting algorithm with linear time complexity is proposed to generate slicing contours for *** method replaces the mesh reconstruction and Boolean operation stages and can efficiently construct complex conformal gradient models of arbitrary topologies through hybrid ***,the time and memory consumption of direct slicing are much lower than those of previous methods when handling hybrid models with hundreds of millions of faces after mesh reconstruction.

关键词： Additive manufacturing(AM) Hybrid modeling Direct slicing Signed distance field

Oxidation behavior of FeV_(2)O_(4)and FeCr_(2)O_(4)particles in the air:Nonisothermal kinetic and reaction mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1839-1848页

作者： Junyi Xiang Xi Lu Luwei Bai Hongru Rao sheng Liu Qingyun huang shengqin Zhang Guishang Pei Xuewei Lü School of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China Department of Materials Science and Engineering Seoul National UniversitySeoul 08826Rep.of Korea College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

High-temperature oxidation behavior of ferrovanadium(FeV_(2)O_(4))and ferrochrome(FeCr_(2)O_(4))spinels is crucial for the application of spinel as an energy material,as well as for the clean usage of high-chromium vanadium ***,the nonisothermal oxidation behavior of FeV_(2)O_(4)and FeCr_(2)O_(4)prepared by high-temperature solid-state reaction was examined by thermogravimetry and X-ray diffraction(XRD)at heating rates of 5,10,and 15 K/*** apparent activation energy was determined by the Kissinger-Akahira-Sunose(KAS)method,whereas the mechanism function was elucidated by the Malek ***,in-situ XRD was conducted to deduce the phase transformation of the oxidation mechanism for FeV_(2)O_(4)and FeCr_(2)O_(4).The results reveal a gradual increase in the overall apparent activation energies for FeV_(2)O_(4)and FeCr_(2)O_(4)during *** stages of the oxidation process are observed based on the oxidation conversion rate of each *** oxidation mechanisms of FeV_(2)O_(4)and FeCr_(2)O_(4)are complex and have distinct *** particular,the chemical reaction controls the entire oxidation process for FeV_(2)O_(4),whereas that for FeCr_(2)O_(4)transitions from a three-dimensional diffusion model to a chemical reaction *** to the in-situ XRD results,numerous intermediate products are observed during the oxidation process of both compounds,eventually resulting in the final products FeVO_(4)and V2O_(5)for FeV_(2)O_(4)and Fe_(2)O_(3)and Cr_(2)O_(3)for FeCr_(2)O_(4),respectively.

关键词： FeV_(2)O_(4) FeCr_(2)O_(4) oxidation nonisothermal kinetics mechanism

High temperature treatment induced production of unreduced 2n pollen in Camellia oleifera

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Horticultural Plant Journal 2024年第3期10卷 879-896页

作者： Hongda Deng Xiaoyu Zhang Song sheng Yuxun huang Ziqi Ye Tongyue Zhang Xing Liu Zhiqiang Han The Laboratory of Forestry Genetics Central South University of Forestry and TechnologyChangshaHunan 410004China Yuelushan Laboratory ChangshaHunan 410128China Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees of Ministry of Education Central South University of Forestry and TechnologyChangshaHunan 410004China National Forest and Seedling Workstation of Hunan Province The Forestry Department of Hunan ProvinceChangshaHunan 410004China

Unreduced gametes through chromosome doubling play a major role in the process of plant *** previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce the 2n pollen formation by high temperature *** study focused on the optimization of the 2n pollen induction technique and the mechanisms of high temperature-induced2n pollen formation in *** found that the optimal protocol for inducing 2n pollen via high temperature was to perform 45℃with4 h at the prophaseⅠstage of the pollen mother cells(PMCs).Meanwhile,high temperature significantly decreased the yield and fertility of2n *** the observation of meiosis,abnormal chromosome and cytological behaviour was discovered under high-temperature treatment,and we confirmed that the formation of 2n pollen is caused by abnormal cell *** on weighted gene co-expression network analysis,fifteen hub genes related to cell cycle control were *** male flower buds were exposed to heat shock,polygalacturonase gene(CoPGX3)was significantly *** inferred that high temperature causes the CoPGX3 gene to be overexpressed and that CoPGX3 is redistributed into the cytosol where it degrades cytoplasmic pectin,which leads to an abnormal cell ***,abnormal cytokinesis resulted in the formation of dyads and triads,and PMCs divided to produce 2n *** findings provide new insights into the mechanism of 2n pollen induced by high temperature in a woody plant and lay a foundation for further ploidy breeding of ***.

关键词： Camellia oleifera Pollen mother cells(PMCs) High temperature Meiosis 2n pollen CoPGX3