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Different mechanisms underlie similar species-area relationships in two tropical archipelagoes

Plant Diversity 2024年第2期46卷 238-246页

作者： Shengchun li Tieyao Tu shaopeng li Xian Yang Yong Zheng liang-Dong Guo Dianxiang Zhang lin Jiang Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China ECNU-Alberta Joint Lab for Biodiversity Study Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China School of Biological Sciences Georgia Institute of TechnologyAtlantaGA 30332USA Jiangxi Academy of Forestry Nanchang 330032China Institute of Eco-Chongming(IEC) Shanghai 202162China State Key Laboratory of Biocontrol School of EcologySun Yat-sen UniversityGuangzhou 510275China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain elusive.Here,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelagoes in the South China Sea.We found positive plant species-area relationships for both coral and continental archipelagoes.However,our results showed that different mechanisms contributed to similar plant species-area relationships between the two archipelagoes.For coral islands,soil nutrients and spatial distance among communities played major roles in shaping plant community structure and species diversity.By contrast,the direct effect of island area,and to a lesser extent,soil nutrients determined plant species richness on continental islands.Intriguingly,increasing soil nutrients availability(N,P,K)had opposite effects on plant diversity between the two archipelagoes.In summary,the habitat quality effect and dispersal limitation are important for regulating plant diversity on coral islands,whereas the passive sampling effect,and to a lesser extent,the habitat quality effect are important for regulating plant diversity on continental islands.More generally,our findings indicate that island plant species-area relationships are outcomes of the interplay of both niche and neutral processes,but the driving mechanisms behind these relationships depends on the type of islands.

关键词： Coral and continental islands Plant diversity Soil nutrients Species-area relationships The sampling effect

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Atomically Dispersed Pt and NiO Clusters Synergistically Enhanced C–O Bond Hydrogenolysis

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CCS Chemistry 2024年第3期6卷 709-718页

作者： Junjuan Yang Sen Luan Minghua Dong Yuxuan Wu Xueqing Xing Xingwu liu Junfeng Xiang Zhijuan Zhao shaopeng li Bin Zhang Huizhen liu Buxing Han Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid and Interface and ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190 School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049 Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsBeijing 100049 National Energy Center for Coal to liquids Synfuels China Co.Ltd.Huairou DistrictBeijing 101400 Center for Physicochemical Analysis and Measurement Institute of ChemistryChinese Academy of SciencesBeijing 100190 Physical Science Laboratory Huairou National Comprehensive Science CenterUniversity of Chinese Academy of SciencesBeijing 100049

C–Obond activation is a highly efficient,fundamental strategy in the depolymerization and hydrodeoxygenation of chemicals with oxygen-containing functional groups such as oil,coal,and biomass.Developing efficient catalysts for C–Oactivation with ultralow-loading noble and non-noble metals is highly desirable for the improvement of metal atomic utilization.Herein,bimetallic catalysts with atomically dispersed Pt and NiO clusters on different supports were fabricated,and the prepared Pt^(δ+)-NiO/Nb_(2)O_(5)and Pt^(δ+)-NiO/TiO_(2)showed outstanding activity for the hydrogenolysis of benzyl phenyl ether with>99%yield of phenol and toluene due to the excellent cooperation of atomically dispersed Pt and NiO clusters.The synergy mechanism between Pt and Ni and their respective roles in the bimetallic catalyst for C–O hydrogenolysis were clearly clarified.These findings deepen our understanding of the synergy of the two active components and are expected to provide new design concepts for the development of multicomponents catalysts.

关键词： bimetallic catalysis synergistic effect C-O bond activation hydrogenolysis hydrogen spillover

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Diagnostic value of aldosterone to renin ratio calculated by plasma renin activity or plasma renin concentration in primary aldosteronism: a meta-analysis

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Chinese Medical Journal 2022年第6期135卷 639-647页

作者： Zhenjie liu Xiaohong Deng li Luo shaopeng li Man li Qinqin Deng Weiguo Zhong Qiang Luo Department of Clinical Laboratory The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhouGuangdong 510120China Department of Clinical Laboratory Guangdong Provincial Hospital of Chinese MedicineGuangzhouGuangdong 510120China Guangzhou University of Chinese Medicine GuangzhouGuangdong 510120China

Background:Since the diagnostic value of aldosterone to renin ratio(ARR)calculated by plasma renin concentration(PRC)or plasma renin activity(PRA)is still inconclusive,we conducted a meta-analysis by systematically reviewing relevant literature to explore the difference in the diagnostic efficacy of ARR calculated by PRC or PRA,so as to provide guidance for clinical diagnosis.Methods:We searched PubMed,Embase,and Cochrane library from the establishment of the database to March 2021.We included studies that report the true positive,false positive,true negative,and false negative values for the diagnosis of primary aldosteronism,and we excluded duplicate publications,research without full text,incomplete information,or inability to conduct data extraction,animal experiments,reviews,and systematic reviews.STATA 15.1 was used to analyze the data.Results:The pooled results showed that ARR(plasma aldosterone concentration[PAC]/PRC)had a sensitivity of 0.82(95%confidence interval[CI]:0.78-0.86),a specificity of 0.94(95%CI:0.92-0.95),a positive-likelihood ratio(LR)of 12.77(95%CI:7.04-23.73),a negative LR of 0.11(95%CI:0.07-0.17),and symmetric area under the curve(SAUC)of 0.982,respectively.Furthermore,the diagnostic odds ratio(DOR)of ARR(PAC/PRC)was 180.21.Additionally,the pooled results showed that ARR(PAC/PRA)had a sensitivity of 0.91(95%CI:0.86-0.95),a specificity of 0.91(95%CI:0.90-0.93),a positive LR of 7.30(95%CI:2.99-17.99),a negative LR of 0.10(95%CI:0.04-0.26),and SAUC of 0.976,respectively.The DOR of ARR(PAC/PRA)was 155.52.Additionally,we conducted a subgroup analysis for the different thresholds(<35 or≥35)of PAC/PRC.The results showed that the DOR of the cut-off≥35 groups was higher than the cut-off<35 groups(DOR=340.15,95%CI:38.32-3019.66;DOR=116.40,95%CI=23.28-581.92).Conclusions:The research results suggest that the determination of ARR(PAC/PRC)and ARR(PAC/PRA)was all effective screening tools for PA.The diagnostic accuracy and diagnostic value of ARR(PAC/PRC)are higher than ARR(PAC/PRA).In addition,within

关键词： Primary aldosteronism Aldosterone to renin ratio Plasma renin activity Plasma renin concentration Diagnostic value Meta-analysis

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Targeted Deposition in a lithiophilic Silver-Modified 3D Cu Host for lithium-Metal Anodes

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Energy & Environmental Materials 2023年第5期6卷 355-363页

作者： Weiyi Chen shaopeng li Chenhui Wang Hui Dou Xiaogang Zhang Jiangsu Key Laboratory of Electrochemical Energy Storage Technologies College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China

lithium-metal batteries are regarded as the"Holy Grail"of next-generation batteries.However,lithium dendrite and anode volume expansion in cycles seriously hinders lithium-metal battery applications.Herein,we propose a precise and efficient strategy for stabilizing lithium-metal batteries via a lithiophilic Ag-modified Cu current host(li@CuM/Ag).By applying the magnetron sputtering method,the lithiophilic silver layer can be anchored homogeneously on the Cu mesh.The lithiophilic silver layer effectively guides uniform li deposition in the 3D host and realizes spatial control over li nucleation.In addition,a dendrite-free lithium anode is successfully realized,which has been proven by in situ optical dynamic tests and li deposition simulations.The symmetrical cell can maintain a low overpotential(230 mV)and long cycle life(90 h)at a large current of 10 mA cm^(-2)for a plating amount of 3 mAh cm^(-2).Furthermore,li@CuM/Ag||liCoO2 cells exhibited a high-capacity retention rate(86.39%)after 150 cycles at 2 C.lithiophilic hosts based on magnetron sputtering provide a feasible strategy for applications of lithium-metal batteries.

关键词： lithiophilic modification lithium-metal battery lithium-metal host magnetron sputtering targeted deposition

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Insight into the formation mechanism and interaction of matrix/TiB whisker textures and their synergistic effect on property anisotropy in titanium matrix composites

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Journal of Materials Science & Technology 2022年第15期110卷 1-13页

作者： Jianwen Le Yuanfei Han Peikun Qiu shaopeng li Guangfa Huang Jianwei Mao Weijie Lu State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Advanced High Temperature Materials and Precision Forming Shanghai 200240China Shanghai Jiao Tong University Baotou Institute of Material Research Baotou 014020China

Considerable studies on processed pure titanium and titanium alloys have proved the possibility of prop-erty anisotropy induced by crystallographic textures,but limited information is available for the intrinsic coupling of matrix and reinforcement textures and their synergistic effect on property anisotropy in tita-nium matrix composite(TMCs).In the present work,an advanced EBSD/EDS coupling method was used to investigate the formation mechanism of primaryαand secondaryαtextures in the matrix alloy.It is revealed for the first time that the reinforcement TiB_(w)displays a{100}texture after hot rolling and has little effect on the matrix texture component but weakens texture intensity.Significant anisotropies in the tensile strength and ductility can be all noted at room and high-temperatures,which is the syn-ergistic effect of the matrix texture and the aligned TiB_(w).The mean Schmid factor of each slip system was calculated to evaluate the influence of matrix texture on the minimum active stress of slip deforma-tion in the different tensile directions.The analysis shows that the strong T-type matrix texture results in higher strength but lower ductility when loaded in the transverse direction.Moreover,a generalized shear-lag model was modified to quantitatively evaluate the strengthening contribution of aligned TiB_(w),which decreases with increasing off-axis angle and test temperature.A new parameter,defined as the critical aspect ratio of the off-axis whisker,was proposed to rationalize why the TiB_(w) failure mechanism converts from TiB_(w) fracture to TiB_(w)/matrix interfacial debonding with increasing off-axis angle and test temperature.

关键词： Titanium matrix composites(TMCs) TiB whiskers Anisotropy Mechanical properties Texture

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Fretting wear behaviour of machined layer of nickel-based superalloy produced by creep-feed profile grinding

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Chinese Journal of Aeronautics 2022年第10期35卷 401-411页

作者： Weijie KUANG Qing MIAO Wenfeng DING Yanjun ZHAO Biao ZHAO Xuebing WEN shaopeng li National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Mechanical Engineering Suzhou University of Science and TechnologySuzhou 215009China State Key Laboratory of Super abrasives Zhengzhou Research Institute for Abrasive&Grinding Co.LtdZhengzhou 450001China AECC Xi'An Aero-Engine LTD Xi'an 710021China

Fretting wear has an adverse impact on the fatigue life of turbine blade roots.The current work is to comparatively investigate the fretting wear behaviour of the nickel-based superalloy surfaces produced by polishing and creep-feed profile grinding,respectively,in terms of surface/subsurface fretting damage,the friction coefficient,wear volume and wear rate.Experimental results show that the granulated tribolayer aggravates the workpiece wear,while the flat compacted tribolayer enhances the wear resistance ability of workpiece,irrespective of whether the workpiece is processed by polishing or grinding.However,the wear behaviors of tribolayers are different.For the polished surface,when the normal load exceeds 100 N,the main defects are crack,rupture,delamination and peeling of workpiece materials;the wear mechanism changes from severe oxidative wear to fatigue wear and abrasive wear when the loads increase from 50 to 180 N.As for the ground surface,the main wear mechanism is abrasive wear.Particularly,the ground surface possesses better wear-resistant ability than the polished surface because the former has the lower values in coefficient friction(0.23),wear volume(0.06×10^(6)μm^(3))and wear rate(0.25×10^(-16)Pa^(-1)).Finally,an illustration is given to characterize the evolution of wear debris on such nickel-based superalloy on the ground surface.

关键词： Creep-feed profile grinding Fretting wear Nickel-based superalloy Tribolayer Wear debris

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基于深度学习的钝体断面外形气动性能高效预测方法

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土木与环境工程学报（中英文） 2024年第1期46卷 122-129页

作者：李少鹏李海李珂重庆大学土木工程学院重庆400045

对于气动性能,钝体断面的气动外形非常重要,采用传统风洞试验及CFD模拟计算得到钝体断面气动性能需消耗大量时间,大大影响钝体断面气动外形的气动性能评估效率。通过卷积神经网络深度学习技术实现对气动性能的快速预测,深度学习模型训... 详细信息

对于气动性能,钝体断面的气动外形非常重要,采用传统风洞试验及CFD模拟计算得到钝体断面气动性能需消耗大量时间,大大影响钝体断面气动外形的气动性能评估效率。通过卷积神经网络深度学习技术实现对气动性能的快速预测,深度学习模型训练完成后,输入形状信息和与形状相关的流场信息,即可输出不同几何形状下的阻力系数,进而得到钝体断面的气动性能。为寻找性能最优的深度学习模型,通过综合判定误差和参数量大小对卷积神经网络结构的深度和宽度进行优化。对深度学习模型输出阻力系数与CFD计算结果进行对比发现,误差符合预期要求,并且相较于传统方法,基于深度学习网络的预测所需时间达到数量级的提升,未来可作为钝体断面气动外形优化的关键方法。

关键词：桥梁静风力钝体断面气动性能深度学习卷积神经网络

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Dynamically modulated synthesis of hollow metal-organic frameworks for selective hydrogenation reactions

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Nano Research 2023年第8期16卷 11334-11341页

作者： liyun Xiao Chuanqi Cheng Zhixi li Chaoyang Zheng Jing Du Meina Song Yue Wan shaopeng li Guo Jun Meiting Zhao Department of Chemistry Institute of Molecular Aggregation ScienceTianjin Key Laboratory of Molecular Optoelectronic SciencesTianjin UniversityTianjin 300072China Institute of New Energy Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300072China State Key Laboratory of Separation Membranes and Membrane Processes School of ChemistryTiangong UniversityTianjin 300387China

Hollow metal-organic frameworks(MOFs)have attracted increasing attention in the field of catalysis in recent years due to their unique cavity structure with fast mass-diffusion rates and easily accessible active sites.Here,we report the use of dynamic modulators,which are formed by the in-situ imine condensation reaction of 4-aminobenzoic acid and 4-formylbenzoic acid,to regulate the growth of MOFs to synthesize well-defined hollow thioether functionalized UiO-67(denoted as H-UiO-67-S)single crystals.After supporting Pd nanoparticles,the designed catalysts Pd@H-UiO-67-S show excellent conversion(>99.9%),selectivity(>99.9%),and stability(10 cycles)in the selective hydrogenation of nitrobenzenes with other reducible groups.Density functional theory calculations and the experimental results reveal that Pd nanoparticles not only selectively adsorb the nitro-groups on nitrobenzene,but also restrict the adsorption of the aniline product,due to the interaction of thioether with Pd in the confined pores of H-UiO-67-S,finally result in a significant increase in selectivity of nitro-hydrogenation.

关键词： hollow structure metal-organic frameworks(MOFs) dynamically modulated synthesis selective hydrogenation nitrobenzene

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Occurrence,leaching behavior,and detoxification of heavy metal Cr in coal gasification slag

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Chinese Journal of Chemical Engineering 2023年第6期58卷 11-19页

作者： Jiangshan Qu Jianbo Zhang Huiquan li shaopeng li Da Shi Ruiqi Chang Wenfen Wu Ganyu Zhu Chennian Yang Chenye Wang CAS Key Laboratory of Green Process and Engineering National Engineering Research Center of Green Recycling for Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100090China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China

Coal gasification slag(CGS)is a type of solid waste produced during coal gasification,in which heavy metals severely restrict its resource utilization.In this work,the mineral occurrence and distribution of typical heavy metal Cr in CGS is investigated.The leaching behavior of Cr under different conditions is studied in detail.Acid leaching-selective oxidation-coprecipitation method is proposed based on the characteristics of Cr in CGS.The detoxification of Cr in CGS is realized,and the detoxification mechanism is clarified.Results show that Cr is highly enriched in CGS.The speciation of Cr is mainly residual fraction(74.47%-86.12%),which is combined with amorphous aluminosilicate.Cr^(3+)and Cr^(6+)account for 90.93%-94.82%and 5.18%-9.07%of total Cr,respectively.High acid concentration and high liquid-solid ratio are beneficial to destroy the lattice structure of amorphous aluminosilicate,thus improving the leaching efficiency of Cr,which can reach 97.93%under the optimal conditions.Acid leaching-selective oxidation-coprecipitation method can realize the detoxification of Cr in CGS.Under the optimal conditions,the removal rates of Fe^(3+)and Cr^(3+)in the leaching solution are 80.99%-84.79%and 70.58%-71.69%,respectively,while the loss rate of Al^(3+)is only 1.10%-3.35%.Detoxification slag exists in the form of Fe-Cr coprecipitation(Fe_(1-x)Cr_xOOH),which can be used for smelting.The detoxification acid leaching solution can be used to prepare inorganic polymer composite coagulant poly-aluminum chloride(PAC).This study can provide theoretical and data guidance for detoxification of heavy metal Cr in CGS and achieve resource utilization of coal gasification solid waste.

关键词： Coal gasification slag Heavy metal Distributions Leaching Detoxification Precipitation

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Crystallization of calcium silicate at elevated temperatures in highly alkaline system of Na_2O–CaO–SiO_2–H_2O

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Chinese Journal of Chemical Engineering 2017年第10期25卷 1539-1544页

作者： Ganyu Zhu Huiquan li shaopeng li Xinjuan Hou Xingrui Wang Key Laboratory of Green Process and Engineering National Engineering Laboratory for Hydrometallurgical Cleaner Production TechnologyInstitute of Process EngineeringChinese Academy of Sciences School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences

In Na_2O–CaO–SiO_2–H_2O system,systematic investigations of phase and morphology of calcium silicate in hydrothermal conditions were concisely conducted for high-value utilization of silicon resource in high-alumina fly ash(HAFA).The results show that crystal composition and phase may be affected by relatively low concentration of NaOH,and sodium ions are rearranged into the structure to form NaCaHSiO_4 and Na_2Ca_3H_8Si_2O_(12) with different C/S ratio at high concentration of Na OH.In addition,phases in wollastonite group possess the morphology of nano fiber.Formation of nano fiber is attributed to the difference of surface energies between axial and radial direction,and higher temperatures lead to easier growth along radial direction.The preparation of C–S–H with different phases and morphologies can guide for the application of silicate solution with high alkalinity with different purposes.

关键词：高温硅酸钙碱性体系结晶系统调查 NaOH 纳米纤维高值化利用高铝粉煤灰

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