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Journal of Forestry Research 2024年第2期35卷 146-162页

作者： yuanyuan wang Xinzhu dai Xingling Chen Dan Zhang Guiqing Lin yuanhang Zhou Tianyi wang yulong Cui Academy of Forestry Sciences of Changchun Bureau of Forestry and Landscaping of ChangchunChangchun 130117People’s Republic of China College of Landscape Architecture Changchun UniversityChangchun 130022People’s Republic of China Changchun South Lake Park Bureau of Forestry and Landscaping of ChangchunChangchun 130012People’s Republic of China

Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of *** clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density *** found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(pdeciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,*** findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.

关键词： Species diversity Forest characteristics Biomass carbon sink Forest-type effect Urbanization effect Urban forests

Effects of hot deformation and in-situ ZrB2 particle on microstructure and tensile performance of AA7085 composite sheets

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Journal of Iron and Steel Research International 2024年第7期31卷 1778-1791页

作者： Jiang-jing Wu Xi-zhou Kai Chuang guan yu-tao Zhao School of Material Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

To provide a new idea to reduce anisotropy for sheets in the thickness direction by microstructure modification and,mean-while,maintain or even enhance tensile performance,the in-situ ZrB2 particle/AA7085 composite sheets with thicknesses of 1,2,3,and 6 mm were *** as-cast grain size was significantly refined by the heterogeneous nucleus of the ZrB2 *** microstructure results show that severe hot deformation converts as-cast disordered microstructure into a sequential microstructure by crushing the remanent phases and matrix into a fiber *** the solid solution and aging heat treatment,the composite sheets exhibit largely recrystallized grains compared with partially recrystallized grains in the matrix sheets,and weak or even free texture exists in the *** grain size in the composite sheets decreases with the increase in thickness *** the thickness range of 1-3 mm,the composite sheets maintain a similar tensile per-formance as that in matrix sheets,while the strength and ductility in the 6-mm-thick composite sheet are improved.

关键词： Composite sheet Grain structure Texture Dislocation Strengthening

UiO-66-NH_(2)nanoparticles supported on layered double hydroxides as an excellent adsorbent for levofloxacin capture

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Particuology 2024年第9期92卷 155-165页

作者： Yan Li Heng Lin Qiaolan yu Na Ma Wei dai College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua321004China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua321004China

The adsorption performances of individual adsorbent such as UiO-66-NH_(2)and MgAl-layered double hydroxides(MgAl-LDH)toward levofloxacin(LVX)is less satisfactory due to the disappointing uptake capacity and adsorption ***,a 3D flower-like composite adsorbent prepared via iterative hydrothermal synthesis method anchoring UiO-66-NH_(2)nanoparticles onto the MgAl-LDH *** to the synergistic effects of UiO-66-NH_(2),and MgAl-LDH,the MgAl-LDH@UiO-66-NH_(2)exhibits an outstanding adsorption performance toward ***,the maximum LVX uptake capacity over MgAl-LDH@UiO-66-NH_(2)reached 268 mg/g,which was higher than that of the individual adsorption materials UiO-66-NH_(2)(41 mg/g),MgAl-LDH(140 mg/g),and some adsorbents reported in previous *** rapid adsorption process can reach equilibrium within 20 min,which conformed well to the pseudo-second-order kinetics and the Langmuir isotherm *** thermodynamic result also indicated that the adsorption was spontaneous and exothermic,simultaneous coexisting physical and chemical adsorption ***,the MgAl-LDH@UiO-66-NH_(2)still maintained excellent adsorption capacity with a slightly decrease after fifth cycle,exhibiting a remarkable reuse and stable *** work provides a highly novel strategy to prepare recyclable composite adsorbent for the LVX capture from aqueous solution.

关键词： Layered double hydroxides UiO-66-NH_(2) LVX Adsorption

Effect of movability of water on the low-velocity pre-Darcy flow in clay soil

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3299-3310页

作者： Hui Cheng Fugang wang Shengwei Li Xiaotong guan Guohua Yang Zhongle Cheng Ceting yu Yilong yuan guanhong Feng Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun130012China Jilin Provincial Key Laboratory of Water Resources and Water Environment Jilin UniversityChangchun130012China Chengdu Center China Geological SurveyChengdu610081China

Water seepage in soil is a fundamental problem involving various scientific and engineering *** to the literature,low-velocity water seepage in low-permeability porous media,such as clay,does not follow Darcy's law,also known as pre-Darcy *** formation of immovable water due to water adsorption on the pore wall is believed to be responsible for the formation of pre-Darcy ***,this view lacks direct solid *** investigate the pre-Darcy water flow in clay,head permeability experiments are conducted on six clay samples with different *** results indicate that water seepage in clay at low hydraulic gradients does not follow Darcy's law.A clear nonlinear relationship between flow velocity and hydraulic gradient is *** flow in clay can be divided into the pre-Darcy flow and Darcy flow regions by the critical hydraulic gradient,which is 10-12 for the Albic soil with dry density between 1.3 g/cm^(3)and 1.8 g/cm^(3).According to the disjoining pressure theory,immovable water due to water adsorption on the pore wall is the primary reason for water flow deviating from Darcy's law in *** results indicate that the percentage of movable water ranges from 39.7%to 59.3%for the six samples at a hydraulic gradient of *** the hydraulic gradient increases,the percentage of moveable water also ***,there is a strong correlation between the percentage of movable water and the variation in hydraulic conductivity with the hydraulic ***,a quantitative relationship between the percentage of movable water and the hydraulic conductivity has been *** results of this study suggest that water adsorption on the pore wall not only affects the water movability,but is also closely related to the pre-Darcy flow phenomenon in clay.

关键词： Pre-Darcy flow Clay Critical hydraulic gradient Water movability analysis

Research on the solid particle erosion wear of pipe steel for hydraulic fracturing based on experiments and numerical simulations

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Petroleum Science 2024年第4期21卷 2779-2792页

作者： Si-Qi Yang Jian-Chun Fan Ming-Tao Liu de-Ning Li Jun-Liang Li Li-Hong Han Jian-Jun wang Shang-yu Yang Si-Wei dai Lai-Bin Zhang State Key Laboratory of Oil and Gas Equipment CNPC Tubular Goods Research Institute Key Laboratory of Oil and Gas Safety and Emergency Technology China University of Petroleum Oil Production Technology Research Institute of Liaohe Oilfield Company Tianjin Gas Storage Branch PetroChina Dagang Oilfield Company Petroleum Production Engineering Research Institute Daqing Oilfield Company

Erosion wear is a common failure mode in the oil and gas industry. In the hydraulic fracturing, the fracturing pipes are not only in high-pressure working environment, but also suffer from the impact of the high-speed solid particles in the fracturing fluid. Beneath such complex conditions, the vulnerable components of the pipe system are prone to perforation or even burst accidents, which has become one of the most serious risks at the fracturing site. Unfortunately, it is not yet fully understood the erosion mechanism of pipe steel for hydraulic fracturing. Therefore, this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical simulations. Firstly, we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the material. The effects of impact angle, flow velocity and applied stress on erosion wear were comprehensively considered. Then a particle impact dynamic model of erosion wear was developed based on the experimental parameters, and the evolution process of particle erosion under different impact angles, impact velocities and applied stress was analyzed. By combining the erosion characteristics, the micro-structure of the eroded area, and the micro-mechanics of erosion damage, the erosion mechanism of pipe steel under fracturing conditions was studied in detail for the first time. Under high-pressure operating conditions, it was demonstrated through experiments and numerical simulations that the size of the micro-defects in the eroded area increased as the applied stress increased, resulting in more severe erosion wear of fracturing pipes.

关键词： Erosion wear Applied stress Particle impact dynamics Erosion mechanism

Engineering of oxygen vacancy and bismuth cluster assisted ultrathin Bi_(12)O_(17)Cl_(2)nanosheets with efficient and selective photoreduction of CO_(2)to CO

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Carbon Energy 2024年第4期6卷 1-11页

作者： Meili guan Ni Lu Xuan Zhang Qiuwan wang Jian Bao Guiye Chen Hao yu Huaming Li Jiexiang Xia Xuezhong Gong College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdaoShandongChina Institute for Energy Research Jiangsu UniversityZhenjiangJiangsuChina National Center of International Joint Research for Hybrid Materials Technology Institute of Hybrid MaterialsCollege of Materials Science andEngineeringNational Base of International Science and Technology Cooperation on Hybrid MaterialsQingdao UniversityQingdaoShandongChina

The photocatalytic conversion of CO_(2)into solar‐powered fuels is viewed as a forward‐looking strategy to address energy scarcity and global *** work demonstrated the selective photoreduction of CO_(2)to CO using ultrathin Bi_(12)O_(17)Cl_(2)nanosheets decorated with hydrothermally synthesized bismuth clusters and oxygen vacancies(OVs).The characterizations revealed that the coexistences of OVs and Bi clusters generated in situ contributed to the high efficiency of CO_(2)–CO conversion(64.3μmol g^(−1)h^(−1))and perfect *** OVs on the facet(001)of the ultrathin Bi_(12)O_(17)Cl_(2)nanosheets serve as sites for CO_(2)adsorption and activation sites,capturing photoexcited electrons and prolonging light absorption due to defect *** addition,the Bi‐cluster generated in situ offers the ability to trap holes and the surface plasmonic resonance *** study offers great potential for the construction of semiconductor hybrids as multiphotocatalysts,capable of being used for the elimination and conversion of CO_(2)in terms of energy and environment.

关键词： Bi cluster Bi_(12)O_(17)Cl_(2)nanosheet oxygen vacancy photocatalytic CO_(2)reduction

Editorial:special topic on heterojunction in photocatalysts

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Science China Materials 2024年第2期67卷 379-381页

作者： Jiaguo yu Xin Li Junwei Fu Kai dai Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou 510642China Hunan Joint International Research Center for Carbon Dioxide Resource Utilization State Key Laboratory of Powder MetallurgySchool of PhysicsCentral South UniversityChangsha 410083China Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation College of Physics and Electronic InformationHuaibei Normal UniversityHuaibei 235000China

To suppress the recombination of photogenerated electron and hole in single photocatalysts,an important method is to design heterojunction by combining two *** method has widely used to enhance the photocatalytic performance of the *** the begining,most people use type-Ⅱcharge carrier transfer mechanism to explain the emhanced activity of the composite semiconductors.

关键词： composite heterojunction method

Non-Gaussian feature of the output field from a double qubit-cavity ultrastrong coupling system

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Communications in Theoretical Physics 2024年第7期76卷 30-36页

作者： Sheng-wen Xu Shi-yu dai Teng Zhao Center for Quantum Science and Technology Jiangxi Normal UniversityNanchang 330022China

We investigate the non-Gaussian feature of radiation in a circuit quantum electrodynamics(QED)system where two qubits are strongly coupled to a single-mode *** the regime of ultrastrong coupling(USC),the rotating-wave approximation is not valid,and the Rabi Hamiltonian contains counter-rotating wave terms,leading to level crossing and avoided crossings in the energy *** further analyze the intensity-amplitude correlation of the output field in these two novel *** the USC regime,the creation and annihilation operators in the correlation function are replaced,allowing for the identification of non-Gaussian features in the output *** findings reveal that despite the absence of squeezing effects in the output light,significant non-Gaussian characteristics are ***,we demonstrate that as the driving or coupling strength increases,the non-Gaussian features of the output field become more *** suggests that USC systems hold broad potential applications in the realms of nonlinear optics and the generation of non-Gaussian states.

关键词： ultrastrong coupling non-Gaussian intensity-amplitude correlation

A Skin-Inspired Self-Adaptive System for Temperature Control During Dynamic Wound Healing

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Nano-Micro Letters 2024年第8期16卷 211-224页

作者： Yaqi Geng Guoyin Chen Ran Cao Hongmei dai Zexu Hu Senlong yu Le wang Liping Zhu Hengxue Xiang Meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua University2999 North Renmin RoadShanghai 201620People’s Republic of China

The thermoregulating function of skin that is capable of maintaining body temperature within a thermostatic state is ***,patients suffering from skin damage are struggling with the surrounding scene and situational ***,we report an interactive self-regulation electronic system by mimicking the human thermos-reception *** skin-inspired self-adaptive system is composed of two highly sensitive thermistors(thermal-response composite materials),and a low-power temperature control unit(Laserinduced graphene array).The biomimetic skin can realize self-adjusting in the range of 35–42℃,which is around physiological *** thermoregulation system also contributed to skin barrier formation and wound *** wound models,the treatment group healed~10%more rapidly compared with the control group,and showed reduced inflammation,thus enhancing skin tissue *** skin-inspired self-adaptive system holds substantial promise for nextgeneration robotic and medical devices.

关键词： Thermo-reception Self-regulation Flexible electronic system Wound healing

Stereospecific Assembly of Trisubstituted Alkenes via Photoinduced Nitrogen-Centered Radical-Triggered C—C Bond Cleavage/Functionalization of Oxime Esters

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Chinese Journal of Chemistry 2024年第12期42卷 1399-1406页

作者： yu Bao Zhi-Jie Song Jin-Long dai Shenghu Yan yue Zhang Jia-Yin wang Guigen Li School of Pharmacy Changzhou UniversityChangzhouJiangsu 213164China department of Chemistry and Biochemistry Texas Tech University79409USA

Comprehensive Summary A general and convenient photoredox-catalyzed acylation and alkylcyanation of MBH acetates has been established,enabling the assembly of the C(sp2)–C(sp3)bond by a nitrogen-centered radical strategy for the synthesis of trisubstituted alkenes in moderate to excellent chemical yields(48 examples in total).The reaction of MBH acetates with acyl(indanone)oxime esters afforded trisubstituted alkenes containing 1,4-dicarbonyl ***,the use of Eosin Y as a photocatalyst in the catalytic system resulted in the formation of distal cyano group-anchored trisubstituted alkenes via deconstructive functionalization of cycloketone oxime ***,these resulting 1,4-dicarbonyl compounds could be applied to late-stage transformations,providing important methods for the synthesis of dihydropyridazin-3(2H)-one.

关键词： Photocatalysis Radical reactions MBH acetates Oxime esters Stereoselectivity Acylation Alkylation Green chemistry