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“Rigid-elastic chimera” pore skeleton model and overpressure porosity measurement method for shale: A case study of the deep overpressure siliceous shale of Silurian Longmaxi Formation in southern Sichuan Basin, SW China

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Petroleum Exploration and Development 2023年第1期50卷 125-137页

作者： shi qiang CHEN Peng PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China

Based on analysis of pore features and pore skeleton composition of shale,a“rigid elastic chimeric”pore skeleton model of shale gas reservoir was built.Pore deformation mechanisms leading to increase of shale porosity due to the pore skeleton deformation under overpressure were sorted out through analysis of stress on the shale pore and skeleton.After reviewing the difficulties and defects of existent porosity measurement methods,a dynamic deformed porosity measurement method was worked out and used to measure the porosity of overpressure Silurian Longmaxi Formation shale under real formation conditions in southern Sichuan Basin.The results show:(1)The shale reservoir is a mixture of inorganic rock particles and organic matter,which contains inorganic pores supported by rigid skeleton particles and organic pores supported by elastic-plastic particles,and thus has a special“rigid elastic chimeric”pore structure.(2)Under the action of formation overpressure,the inorganic pores have tiny changes that can be assumed that they don’t change in porosity,while the organic pores may have large deformation due to skeleton compression,leading to the increase of radius,connectivity and ultimately porosity of these pores.(3)The“dynamic”deformation porosity measurement method combining high injection pressure helium porosity measurement and kerosene porosity measurement method under ultra-high variable pressure can accurately measure porosity of unconnected micro-pores under normal pressure conditions,and also the porosity increment caused by plastic skeleton compression deformation.(4)The pore deformation mechanism of shale may result in the"abnormal"phenomenon that the shale under formation conditions has higher porosity than that under normal pressure,so the overpressure shale reservoir is not necessarily“ultra-low in porosity”,and can have porosity over 10%.Application of this method in Well L210 in southern Sichuan has confirmed its practicality and reliability.

关键词： shale gas “rigid-elastic chimera”pore model “dynamic”deformation porosity deep shale layers Silurian Longmaxi Formation Sichuan Basin

Adaptive strategies of high and low nucleic acid prokaryotes in response to declining resource availability and selective grazing by protozoa

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Science China Earth Sciences 2024年第6期67卷 1872-1884页

作者： Chen HU Liuqian YU Xiaowei CHEN Jihua LIU Yao ZHANG John BATT Xilin XIAO qiang shi Rui ZHANG Tingwei LUO Nianzhi JIAO Dapeng XU College of the Environment and Ecology Xiamen UniversityXiamen 361102China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesFujian Key Laboratory of Marine Carbon SequestrationXiamen UniversityXiamen 361102China Joint Lab for Ocean Research and Education(LORE)of Dalhousie University Canadaand Shandong University and Xiamen UniversityXiamen 361102China Earth Ocean and Atmospheric Sciences ThrustThe Hong Kong University of Science and Technology(Guangzhou)Guangzhou 510000China Institute of Marine Science and Technology Shandong UniversityQingdao 266237China Department of Oceanography Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada Institute for Advanced Study Shenzhen UniversityShenzhen 518060China Carbon Neutral Innovation Research Center Xiamen UniversityXiamen 361102China

Prokaryotes play a fundamental role in global ocean biogeochemical cycles.However,how the abundance and metabolic activity of ecologically distinct subgroups(i.e.,high nucleic acid(HNA)and low nucleic acid(LNA)cells),and their regulating factors,change in response to changing marine environmental conditions remains poorly understood.Here,we delved into the time-evolving dynamic responses of the HNA and LNA prokaryotic subgroups to declining resource availability and selective grazing by protozoa by conducting a 73-day incubation experiment in a large-volume(117,000 L)macrocosm that facilitates community-level exploration.We found that the metabolic activity of the HNA subgroup was higher than that of the LNA subgroup when the macrocosm was resource replete but that the HNA subgroup declined more rapidly than the LNA subgroup as the resources became increasingly scarce,leading to a steadily increasing contribution of LNA cells to prokaryotic activity.Meanwhile,as resources in the macrocosm became limited,protozoan grazing preference shifted from the HNA to the LNA subgroup and the contributions of the LNA subgroup to the carbon flow within the macrocosm increased.The findings highlight the resilience of LNA cells in resource-limited environments,illuminate the critical role of selective grazing by protozoa in balancing distinct prokaryotic subgroups under changing resource conditions,and demonstrate the complex and adaptive interactions between protozoa and prokaryotes across diverse environmental contexts.

关键词： Microbial loop Macrocosm experiment Prokaryote Top-down and bottom-up controls Carbon flow

DIR:Dynamic Request Interleaving for Improving the Read Performance of Aged Solid-State Drives

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Journal of Computer Science & Technology 2024年第1期39卷 82-98页

作者：聂世强张驰伍卫国 Department of Computer Science and Technology Xi'an Jiaotong UniversityShaanci 710049China

Triple-level cell(TLC)NAND flash is increasingly adopted to build solid-state drives(SSDs)for modern computer systems.While TLC NAND flash effectively improves storage density,it faces severe reliability issues;in partic-ular,the pages exhibit different raw bit error rates(RBERs).Integrating strong low-density parity-check(LDPC)code helps to improve reliability but suffers from prolonged and proportional read latency due to multiple read retries for worse pages.The straightforward idea is that dispersing page-size data across several pages in different types can achieve a low-er average RBER and reduce the read latency.However,directly implementing this simple idea into flash translation lay-er(FTL)induces the read amplification issue as one logic page residing in more than one physical page brings several read operations.In this paper,we propose the Dynamic Request Interleaving(DIR)technology for improving the performance of TLC NAND flash-based SSDs,in particular,the aged ones with large RBERs.DIR exploits the observation that the la-tency of an I/O request is determined,without considering the queuing time,by the access of the slowest device page,i.e.,the page that has the highest RBER.By grouping consecutive logical pages that have high locality and interleaving their encoded data in different types of device pages that have different RBERs,DIR effectively reduces the number of read re-tries for LDPC with limited read amplification.To meet the requirement of allocating hybrid page types for interleaved data,we also design a page-interleaving friendly page allocation scheme,which splits all the planes into multi-plane re-gions for storing the interleaved data and single-plane regions for storing the normal data.The pages in the multi-plane re-gion can be read/written in parallel by the proposed multi-plane command and avoid the read amplification issue.Based on the DIR scheme and the proposed page allocation scheme,we build DIR-enable FTL,which integrates the proposed schemes into the FTL with some modificatio

关键词： triple-layer cell solid-state drive(TLC SSD) performance interleaving data unbalanced bit error rate

Low-noise and low-power pixel sensor chip for gas pixel detectors

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Nuclear Science and Techniques 2024年第3期35卷 142-152页

作者： Zhuo Zhou shi-qiang Zhou Dong Wang Xiang-Ming Sun Chao-Song Gao Peng-Zhen Zhu Wei-Ping Ren Jun Liu Mu-Xian Li Chen Lian Chun-Lai Dong PLAC Key Laboratory of Quark and Lepton Physics(MOE)Central China Normal UniversityWuhan 430079China

Topmetal-M2 is a large-area pixel sensor chip fabricated using the GSMC 130 nm CMOS process in 2021.The pixel array of Topmetal-M2 consists of pixels of 400 rows×512 columns with a pixel pitch of 45μm×45μm.The array is divided into 16 subarrays,with pixels of 400 rows×32 columns per subarray.Each pixel incorporates two charge sensors:a diode sensor and a Topmetal sensor.The in-pixel circuit primarily consists of a charge-sensitive amplifier for energy measurements,a discriminator with a peak-holding circuit,and a time-to-amplitude converter for time-of-arrival measurements.The pixel of Topmetal-M2 has a charge input range of~0-3 k e-,a voltage output range of~0-180 mV,and a charge-voltage conversion gain of~59.56μV∕e-.The average equivalent noise charge of Topmetal-M2,which includes the readout electronic system noise,is~43.45 e-.In the scanning mode,the time resolution of Topmetal-M2 is 1 LSB=1.25μs,and the precision is^()7.41μs.At an operating voltage of 1.5 V,Topmetal-M2 has a power consumption of~49 mW∕cm~2.In this article,we provide a comprehensive overview of the chip architecture,pixel working principles,and functional behavior of Topmetal-M2.Furthermore,we present the results of preliminary tests conducted on Topmetal-M2,namely,alpha-particle and soft X-ray tests.

关键词： Charge collection Gas detectors Semiconductor detectors X-ray detectors

Application of UiO-66 and its composites for remediation and resource recovery of typical environmental contaminants:a review

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Rare Metals 2024年第6期43卷 2498-2526页

作者： Hui-Min Zhang Yun-Long Wang Xin-Feng Zhu Zhen-Zhen Huang Dan-Dan Pang Kai Wang Chao-Hai Wang Zhong-Xian Song shi-qiang Yin Lin-Lin Chang Jin-Hui Zhang School Infirmary Henan University of Urban Construction Faculty of Environmental and Municipal Engineering Henan Key Laboratory of Water Pollution Control and Rehabilitation TechnologyKey Laboratory of Carbon Emission Reduction and Combined Air Pollution Control TechnologyHenan University of Urban Construction School of Resources & Environment Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic RegionHenan Polytechnic University The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationGuangzhou Higher Education Mega CentreSouth China University of Technology

UiO-66 series metal-organic framework materials（MOFs） are typical porous materials assembled by Zr4+with a large mass-to-nucleus ratio and terephthalic acid ligands,which form tetrahedral and octahedral cages arranged in a periodic triangular window pattern.Due to the strong interaction between Zr and O,UiO-66 series MOFs exhibit high thermal stability,structural stability,and chemical stability.This article mainly reviews the applications of UiO-66 and its composites in adsorption,photocatalysis,and resource utilization,while exploring the harm of pollutants to human health and the environment.In the first part,the differences in adsorption and removal mechanisms of liquid organic pollutants,heavy metals,and volatile organic compounds（VOCs） are investigated.The results show that organic pollutants are mainly removed by physical adsorption,electrostatic interactions,hydrogen bonding,and π-π interactions,while heavy metals are mainly removed by chemical adsorption,electrostatic interactions,reduction,and chelation.VOCs are mainly removed by the pore volume and pore size structure of the material.Heterojunction catalysis can achieve non-toxic treatment of pollutants,and this study mainly focuses on UiO-based composite materials constructed by strategies such as semiconductor composites,ion doping,and metal/dye encapsulation.In the second part,the synergistic effect between the components of UiO-based composite materials promotes the oriented and rapid separation and transfer of earriers at the material interface,thereby promoting the generation of active species such as h+,·O2-and ·OH,and achieving rapid degradation of pollutants and detoxification of heavy metals.In the third part,heterojunctions can realize the resource utilization of pollutants in water and air,producing energy-type substances such as hydrogen and methanol while solving environmental problems.In addition,this article also summarizes the harm of common typical pollutants to the environment and human health.Finally,the development prospects and un

关键词： UiO Adsorption Photocatalysis Environmental pollution Resource recovery

Theoretical methods for excited state dynamics of molecules and molecular aggregates

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Science China Chemistry 2013年第9期56卷 1271-1276页

作者： shi qiang CHEN Hui Beijing National Laboratory for Molecular Science (BNLMS) Institute of ChemistryChinese Academy of Sciences

This contribution provides a summary of proposed theoretical and computational studies on excited state dynamics in molecular aggregates, as an important part of the National Natural Science Foundation (NNSF) Major Project entitled "Theoretical study of the low-lying electronic excited state for molecular aggregates". This study will focus on developments of novel methods to simulate excited state dynamics of molecular aggregates, with the aim of understanding several important chemical physics processes, and providing a solid foundation for predicting the opto-electronic properties of organic functional materials and devices. The contents of this study include: (1) The quantum chemical methods for electronic excited state and electronic couplings targeted for dynamics in molecular aggregates; (2) Methods to construct effective Hamiltonian models, and to solve their dynamics using system-bath approaches; (3) Non-adiabatic mixed quantum-classic methods targeted for molecular aggregates; (4) Theoretical studies of charge and energy transfer, and related spectroscopic phenomena in molecular aggregates.

关键词：分子聚集体电子激发态动力学模拟量子化学方法有机功能材料自然科学哈密顿模型组成部分

富里酸改性FeMnNi-LDH对砷镉污染土壤的钝化修复

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中国环境科学 2024年第4期44卷 2184-2197页

作者：何雅馨魏世强蒋珍茂西南大学资源环境学院重庆市农业资源与环境研究重点实验室重庆400715

选用腐殖质活性组分富里酸(FA)作为铁锰镍层状双氢氧化物(FeMnNi-LDH)的修饰物,采用共沉淀法制备出稳定层状FA@FeMnNi-LDH复合材料,并运用于As(Ⅲ)和Cd(Ⅱ)复合污染土壤的钝化修复.通过小白菜盆栽实验研究了在不同砷镉复合污染水平及不... 详细信息

选用腐殖质活性组分富里酸(FA)作为铁锰镍层状双氢氧化物(FeMnNi-LDH)的修饰物,采用共沉淀法制备出稳定层状FA@FeMnNi-LDH复合材料,并运用于As(Ⅲ)和Cd(Ⅱ)复合污染土壤的钝化修复.通过小白菜盆栽实验研究了在不同砷镉复合污染水平及不同初始土壤pH值条件下,复合材料对土壤As(Ⅲ)和Cd(Ⅱ)的钝化效果、各形态含量变化及对小白菜根部和地上部As(Ⅲ)和Cd(Ⅱ)转运、富集系数的影响,并进行相关性分析.结果表明,FA@FeMnNi-LDH复合材料对As和Cd具有显著的同步钝化效果.当复合材料添加量由0%增加到1.0%,促进了土壤非专性吸附态和结晶铁铝氧化物结合态As向专性吸附态、无定型铁铝氧化物结合态和残渣态As转化,土壤可交换态Cd主要向残渣态、碳酸盐结合态、铁锰氧化物结合态和有机结合态Cd转化;土壤初始pH对As和Cd的钝化效果影响明显,酸性和中性土壤的pH分别增加了1.65和0.64个pH单位,土壤有效态As的降低率分别达到69.74%和63.31%,有效态Cd的降低率分别为60.25%和61.78%;小白菜的鲜重和株高随复合材料添加量的增加而提高,并且复合材料添加量的增加降低了小白菜各部位对As和Cd的转运和富集系数,使小白菜地上部As、Cd的浓度均低于国家食品安全标准限值.相关性分析显示,非专性吸附态As、可交换态Cd与土壤pH值呈极显著负相关性,残渣态As和Cd与土壤pH呈现极显著正相关,小白菜地上部分和根部中As和Cd的含量与土壤残渣态As和Cd呈极显著负相关关系.FA@FeMnNi-LDH复合材料能提高土壤pH值,促进土壤As和Cd向残渣态的转化,从而降低土壤As和Cd生物有效性和在小白菜植株中的累积,为土壤中As(Ⅲ)和Cd(Ⅱ)复合污染的同步修复提供了新的参考.

关键词：层状双金属氢氧化物(LDH) 富里酸(FA) 改性砷镉复合污染土壤钝化修复

金属氢化物中质子耦合电子转移反应的理论研究

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Chinese Journal of Chemical Physics 2024年第2期37卷 199-210,I0102页

作者：刘晓云但晓寒史强中国科学院化学研究所分子动态与稳态结构国家重点实验室北京分子科学国家研究中心北京100190 中国科学院大学北京100049

金属-氢配合物在多种催化反应中起着重要作用最近的研究表明,与吡啶基团共价连接的钨氢配合物可以发生协同的质子耦合电子转移反应.本文使用密度泛函理论和非绝热速率理论研究了该类弱氢键体系中的协同质子耦合电子转移反应.首先通过密... 详细信息

金属-氢配合物在多种催化反应中起着重要作用最近的研究表明,与吡啶基团共价连接的钨氢配合物可以发生协同的质子耦合电子转移反应.本文使用密度泛函理论和非绝热速率理论研究了该类弱氢键体系中的协同质子耦合电子转移反应.首先通过密度泛函理论构建了金属-氢配合物质子自由度的二维势能面.然后求解薛定方程得到了波函数和振动能级,并用于分析各对振动态之间的跃迁速率和总的速率常数.结果表明,由于质子给体-受体之间距离的热涨落,即使在质子给体和受体之间仅存在弱氢键的情况下,协同质子耦合电子转移反应和总反应速率常数也可以得到显著增强.

关键词：质子耦合电子转移速率常数密度泛函理论计算非绝热跃迁

Young air pollution researcher fascinated by taking pictures of starry skies

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Changjiang Weekly 2022年第16期 7-8页

作者： shi qiang 不详

Ou Changhong.a second year gradvate student maloring in air pllution prevention of the Zhongnan Untversiy of Economics and Low ZUEL.has combined his research with pholographing the slory sky and has produced works wit... 详细信息

关键词： uniquely prevention pollution