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Natural forests exhibit higher organic carbon concentrations and recalcitrant carbon proportions in soil than plantations: a global data synthesis

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JOURNAL OF FORESTRY RESEARCH 2024年第1期35卷 1-11页

作者： Nie, Xiuqing Wang, Hui Wang, jian liu, Shirong Chinese Acad Forestry Ecol & Nat Conservat Inst Key Lab Forest Ecol & Environm Natl Forestry & Gra 2 Dongxiaofu Beijing 100091 Peoples R China

Different chemical compositions of soil organic carbon (SOC) affect its persistence and whether it significantly differs between natural forests and plantations remains unclear. By synthesizing 234 observations of SOC chemical compositions, we evaluated global patterns of concentration, individual chemical composition (alkyl C, O-alkyl C, aromatic C, and carbonyl C), and their distribution evenness. Our results indicate a notably higher SOC, a markedly larger proportion of recalcitrant alkyl C, and lower easily decomposed carbonyl C proportion in natural forests. However, SOC chemical compositions were appreciably more evenly distributed in plantations. Based on the assumed conceptual index of SOC chemical composition evenness, we deduced that, compared to natural forests, plantations may have higher possible resistance to SOC decomposition under disturbances. In tropical regions, SOC levels, recalcitrant SOC chemical composition, and their distributed evenness were significantly higher in natural forests, indicating that SOC has higher chemical stability and possible resistance to decomposition. Climate factors had minor effects on alkyl C in forests globally, while they notably affected SOC chemical composition in tropical forests. This could contribute to the differences in chemical compositions and their distributed evenness between plantations and natural stands.

关键词： Global data synthesis Natural forest Plantations Soil organic carbon Soil organic carbon chemical composition STATE C-13 NMR SPATIAL-DISTRIBUTION MICROBIAL COMMUNITY MATTER FRACTIONS QUALITY SEQUESTRATION STABILIZATION DECOMPOSITION DIVERSITY

Liquid-phase epitaxial layer by layer brushing fabrication of metalorganic frameworks films

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Nano Research 2024年第6期17卷 5698-5704页

作者： Li-Mei Chang Rui Zhai Zhi-zhou Ma jian-Dong Huang Zhi-Gang Gu jian Zhang College of Chemistry Fuzhou UniversityFuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

Development of metal-organic framework(MOF)films is of great importance to expand their ***,we report a facile and universal method of liquid-phase epitaxial(LPE)layer by layer(LBL)brushing approach for fabricating MOF films on various substrates in a high-throughput *** MOF films preparation method offers a great prospective to cost-effectively construct films with short preparation time and little reagent ***,this LBL brushing approach has been implemented successfully to assemble various MOF films,including HKUST-1,zeolitic imidazolate framework-8(ZIF-8),Cu(bdc),and Cu_(2)(L)_(2)P(L=bdc,ndc,and cam;P=dabco and bipy).Afterwards,the classic MOF HKUST-1 and ZIF-8 films were grown on sensor chip electrode and porous fiber support for good volatile organic compounds(VOCs)selective sensing and water purification *** study demonstrates that this LBL brushing preparation method can be employed to synthesize various MOF films with a variety of characteristics to realize their sensing and separation applications.

关键词： metal-organic framework porous materials layer by layer fabrication film

NAD(P)H inspired CO_(2) reduction and beyond

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Science China Chemistry 2024年第4期67卷 1044-1046页

作者： Wenjin Dong jian liu Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesShandong Energy InstituteQingdao 266101China

The catalytic reduction of carbon dioxide to fuels and valueadded chemicals under mild conditions is recognized as a promising strategy to alleviate the energy *** the Calvin cycle of natural photosynthesis,CO_(2)reduction is achieved using cofactor nicotinamide adenine dinucleotide phosphate(NADPH)as a practical catalyst,shedding light on the biomimetic metal-free reduction of CO_(2).

关键词： dioxide dinucleotide catalyst

Turbulent Image Restoration in Atmosphere with Cyclopean Processing via Binocular Fusion

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Chinese Physics Letters 2024年第8期41卷 33-38页

作者： Han Yao Jin-Yan Lin Li-Bang Chen Yi-Kun liu jian-Ying zhou State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-Sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing School of Physics and AstronomySun Yat-Sen University(Zhuhai Campus)Zhuhai 519082China

The outstanding issue to overcoming atmospheric turbulence on distant imaging is a fundamental interest and technological *** propose a novel scenario and technique to restore the optical image in turbulent environmental by referring to Cyclopean image with binocular *** human visual intelligence,image distortion resulting from the turbulence is shown to be substantially *** simulation results taking into account of the atmospheric turbulence,optical image system,image sensors,display and binocular vision perception are presented to demonstrate the robustness of the image restoration,which is compared with a single channel planar optical imaging and *** involving binocular telescope,image recording and the stereo-image display is conducted and good agreement is obtained between the simulation with perceptive experience.A natural extension of the scenario is to enhance the capability of anti-vibration or anti-shaking for general optical imaging with Cyclopean image.

关键词： image turbulence shaking

The reaction mechanism and interfacial crystallization of Al nanoparticle-embedded Ni under shock loading

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Defence Technology（防务技术） 2024年第3期33卷 114-124页

作者： Yifan Xie jian-Li Shao Rui liu Pengwan Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Explosion Protection and Emergency Disposal Technology Engineering Research Center of the Ministry of Education Beijing100039China

The shock-induced reaction mechanism and characteristics of Ni/Al system,considering an Al nanoparticle-embedded Ni single crystal,are investigated through molecular dynamics *** the shock melting of Al nanoparticle,interfacial crystallization and dissolution are the main *** reaction degree of Al particle first increases linearly and then logarithmically with time driven by rapid mechanical mixing and following *** reaction rate increases with the decrease of particle diameter,however,the reaction is seriously hindered by interfacial crystallization when the diameter is lower than 9 nm in our ***,we found a negative exponential growth in the fraction of crystallized Al atoms,and the crystallinity of B2-NiAl(up to 20%)is positively correlated with the specific surface area of Al *** can be attributed to the formation mechanism of B2-NiAl by structural evolution of finite mixing layer near the collapsed *** shock melting of both Al particle and Ni matrix,the liquid-liquid phase inter-diffusion is the main reaction mechanism that can be enhanced by the formation of internal *** addition,the enhanced diffusion is manifested in the logarithmic growth law of mean square displacement,which results in an almost constant reaction rate similar to the mechanical mixing process.

关键词： Shock-induced reaction Molecular dynamics simulations Interfacial crystallization Reaction mechanism

A review of reservoir damage during hydraulic fracturing of deep and ultra-deep reservoirs

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Petroleum Science 2024年第1期21卷 384-409页

作者： Kun Zhang Xiong-Fei liu Dao-Bing Wang Bo Zheng Tun-Hao Chen Qing Wang Hao Bai Er-Dong Yao Fu-jian zhou National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing102249China School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing102617China Tuha Downhole Operation Company CNPC Xibu Drilling Engineering Company LimitedShanshan838200XinjiangChina

Deep and ultra-deep reservoirs have gradually become the primary focus of hydrocarbon exploration as a result of a series of significant discoveries in deep hydrocarbon exploration *** reservoirs present unique challenges due to their deep burial depth(4500-8882 m),low matrix permeability,complex crustal stress conditions,high temperature and pressure(HTHP,150-200℃,105-155 MPa),coupled with high salinity of formation ***,the costs associated with their exploitation and development are exceptionally *** deep and ultra-deep reservoirs,hydraulic fracturing is commonly used to achieve high and stable *** hydraulic fracturing,a substantial volume of fluid is injected into the ***,statistical analysis reveals that the flowback rate is typically less than 30%,leaving the majority of the fluid trapped within the ***,hydraulic fracturing in deep reservoirs not only enhances the reservoir permeability by creating artificial fractures but also damages reservoirs due to the fracturing fluids *** challenging“three-high”environment of a deep reservoir,characterized by high temperature,high pressure,and high salinity,exacerbates conventional forms of damage,including water sensitivity,retention of fracturing fluids,rock creep,and proppant *** addition,specific damage mechanisms come into play,such as fracturing fluid decomposition at elevated temperatures and proppant diagenetic reactions at HTHP ***,the foremost concern in deep oil and gas development lies in effectively assessing the damage inflicted on these reservoirs by hydraulic fracturing,comprehending the underlying mechanisms,and selecting appropriate ***'s noteworthy that the majority of existing studies on reservoir damage primarily focus on conventional reservoirs,with limited attention given to deep reservoirs and a lack of systematic *** light of this,our approach entails initially summarizin

关键词： Artificial fracture Deep and ultra-deep reservoir Fracture conductivity Fracturing fluid Hydraulic fracturing Reservoir damage

Community Incidence Estimates of Five Pathogens Based on Foodborne Diseases Active Surveillance—China,2023

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China CDC weekly 2024年第24期6卷 574-579,I0002页

作者： Penghui Fan Haihong Han Jikai liu Xiaochen Ma Ronghua Zhang Hong liu Yijing zhou Zunhua Chu jian Wen Li Lin Weiwei Li Yunchang Guo NHC Key Laboratory of Food Safety Risk Assessment China National Center for Food Safety Risk AssessmentBeijingChina Beijing Center for Disease Prevention and Control BeijingChina Zhejiang Provincial Center for Disease Control and Prevention Hangzhou CityZhejiang ProvinceChina Shanghai Center for Disease Control and Prevention ShanghaiChina jiangsu Provincial Center for Disease Control and Prevention Nanjing CityJiangsu ProvinceChina Shandong Province Center for Disease Control and Prevention Jinan CityShandong ProvinceChina Guangdong Province Center for Disease Control and Prevention Guangzhou CityGuangdong ProvinceChina Sichuan Province Center for Disease Control and Prevention Chengdu CitySichuan ProvinceChina

Summary What is already known about this topic?Foodborne diseases,representing significant food safety and public health challenges globally,are not welldocumented in terms of incidence,particularly for cases characterized by acute gastroenteritis(AGI)in *** is added by this report?This study developed a pyramid model to estimate the incidence of five pathogens,stratified by gender and age.

关键词： acute diseases stratified

A tree-growing graphic model for asymmetrical phantom networks in polymeric gels undergoing dynamic mechanochemical coupling

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Science China(Technological Sciences) 2024年第2期67卷 558-567页

作者： SHI WeiLin zhou jian LU HaiBao ELMARAKBI Ahmed FU Yong-Qing National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Faculty of Engineering and Environment University of NorthumbriaNewcastle upon Tyne NEI 8STUK

Network structures of various polymers have significant effects on their mechanical properties;therefore,numerous studies have investigated the constitutive relationship between symmetrical network structures and their rubber elasticity in ***,few studies have focused on asymmetrical network structures in polymers that undergo bond exchange reactions,selfassembly,or mechanochemical coupling—all of which are induced by transition probabilities of chemical bonding *** this study,an extended constraint junction and phantom network model is formulated using the tree-growing theory to establish a constitutive relationship between asymmetrical network structures and their rubber elasticity in polymers.A free-energy equation is further developed to explore working principles of configurational transitions on the dynamic rubber elasticity of symmetrical and asymmetrical network *** constitutive relationship between dynamic rubber elasticity and symmetrical and asymmetrical network structures has also been proposed for the gels undergoing mechanochemical and hydromechanical ***,the effectiveness of this newly proposed tree-growing model has been verified by comparing with the classical affine network model,finite element analysis,and the experimental results of gels reported in literature.

关键词： gel polymer network rubber elasticity asymmetric

Hemodynamics of Ophthalmic Artery and Central Retinal Artery and Correlation with Other Factors in Patients with Primary Open Angle Glaucoma

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眼科学报 1998年第3期14卷 138-144页

作者： Xing liu, jian Ge, Wenbing zhou, Yunlan Lin, Xiaoyu CaiZhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou 510060, China Zhongshan Ophthalmic Center Sun Yat-sen University of Medical Sciences Guangzhou 510060 China

Objective : To investigate the hemodynamics of ophthalmic artery (OA) and central retinal artery (CRA) in patients with primary open angle glaucoma(POAG) and analyse the correlation between hemodynamics of OA and CRA and other ***:The hemodynamics of OA and CRA in normal persons (102 eyes) and glaucoma-tous patients (102 eyes) were measured by Colour Doppler Image (GDI). The linear correlation analysis was made between OA and CRA about each of the following parameters: the peak systolic flow velocity (Vmax), the end diastolic velocity (Vmin). The multiple step-wise regression analysis was taken to investigate the correlation between each of the following hemodynamics of OA and CRA; Vmax and Vmin in 74 eyes with POAG and each of the following related factors in hemorrheology; whole blood apparent viscosity at low, medium and high shear rate, plasma viscosity and hematocrit. The multiple linear regression was applied to investigate the correlation between each of the following hemodynamics

关键词：血液动力学眼动脉中心视网膜动脉开角型青光眼