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基于Geo-Studio与渗流试验的寒区堤防工程安全性研究

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水利科技与经济 2024年第6期30卷 79-84页

作者：李翠兰王冶志东港市水资源服务中心辽宁东港118300

在寒区堤防工程中,对渗流现象进行充分的分析和了解,才能对堤防工程安全性进行有效管理和控制。基于Geo-Studio软件,对某寒区堤防工程进行模拟渗流试验,并结合有限差分法,模拟分析渗流影响。结果显示,凌汛期春汛水位最高流速约为1.94m/d... 详细信息

在寒区堤防工程中,对渗流现象进行充分的分析和了解,才能对堤防工程安全性进行有效管理和控制。基于Geo-Studio软件,对某寒区堤防工程进行模拟渗流试验,并结合有限差分法,模拟分析渗流影响。结果显示,凌汛期春汛水位最高流速约为1.94m/d,渗透流速由0.39m/d升至8.95m/d,梯度变化微小;非凌汛期特征水位渗透流速、梯度几乎在2以下,表明是否处于凌汛期对梯度影响较小,对渗透流速影响较大。研究方法对寒区堤防工程安全性管控具有一定的参考价值。

关键词：渗流堤防工程 Geo-Studio 有限差分法

A Facile li2TiO3 Surface Modification to Improve the Structure Stability and Electrochemical Performance of Full Concentration Gradient li-Rich Oxides

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Energy & Environmental Materials 2024年第3期7卷 45-52页

作者： Naifang Hu Yuan Yang lin li Yuhan Zhang Zhiwei Hu lan Zhang Jun Ma Guanglei cui Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences Institute of Materials Science and Engineering Ocean University of China School of Future Technology University of Chinese Academy of Sciences Max Planck Institute for Chemical Physics of Solids CAS Key Laboratory of Green Process and Engineering Beijing Key Laboratory of Ionic Liquids Clean ProcessState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of Sciences Shandong Energy Institute

Full concentration gradient lithium-rich layered oxides are catching lots of interest as the next generation cathode for lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rate performance,whereas the high lithium residues on its surface impairs the structure stability and long'term cycle performance. Herein,a facile multifunctional surface modification method is implemented to eliminate surface lithium residues of full concentration gradient lithium-rich layered oxides by a wet chemistry reaction with tetrabutyl titanate and the post-annealing process. It realizes not only a stable li2TiO3coating layer with 3D diffusion channels for fast li+ions transfer,but also dopes partial Ti4+ions into the sub-surface region of full concentration gradient lithium-rich layered oxides to further strengthen its crystal structure. Consequently,the modified full concentration gradient lithium-rich layered oxides exhibit improved structure stability,elevated thermal stability with decomposition temperature from 289.57℃to321.72℃,and enhanced cycle performance (205.1 mAh g-1after 150 cycles)with slowed voltage drop （1.67 mV per cycle）. This work proposes a facile and integrated modification method to enhance the comprehensive performance of full concentration gradient lithium-rich layered oxides,which can facilitate its practical application for developing higher energy density lithium-ion batteries.

关键词： full concentration gradient lithium-rich layered oxides structure stability surface modification

Inhibiting water evaporation of sandy soil by the soil particles modified with Japanese wax

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Journal of Forestry Research 2009年第1期20卷 59-62页

作者： ZHANG Zeng-Zhi WANG Hong-Juan li cui-lan Research institute of Ecological and Functional Material China University of Mining and Technology Beijing 100083

This study was conducted to resolve the problems of water conservation of sandy soil in desertification areas. The surface of soil particles was modified by molecules of natural Japanese wax through some specially screened surfactant. The modified particles were then well sprayed onto the sand, which was placed in an artificial climate box with simulating desert environment, to form a soil film with effect of suppressing water and gas-permeability. Structure of soil film was analyzed by means of X-ray diftYaction （XRD） and infrared spectrometry （IR）. And its mechanism of water inhibition was illustrated with DSC and TG curves. Its influence on grass-planting was tested through the instruments of water detector. The results show that sorbitol anhydride stearate （ Span 80） could well disperse the Japanese wax and make it combine with the clay which is also dispersed. The pores among soil particles grew smaller and turned from hydrophilic into hydrophobic, in which way resistance to water penetrating through the film was increased. Experimental grass grows normally on sandy soil with the soil film in the artificial desert climate box, indicating that the soil particles modified with Japanese wax is an effective method to inhibit water evaporation.

关键词： Japanese wax surfactant desert soil hydrophobic soil film

Adsorption of Cu(Ⅱ) on humic acids derived from different organic materials

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Journal of Integrative Agriculture 2015年第1期14卷 168-177页

作者： li cui-lan JI Fan WANG Shuai ZHANG Jin-jing GAO Qiang WU Jing-gui ZHAO lan-po WANG li-chun ZHENG li-rong College of Resource and Environmental Science Jilin Agricultural University Institute of Plant Science Jilin Agricultural Science and Technology College Institute of Agricultural Resources and Environments Jilin Academy of Agricultural Sciences Institute of High Energy Physics Chinese Academy of Sciences

The adsorption of Cu（Ⅱ） from aqueous solution onto humic acid （HA） which was isolated from cattle manure （CHA）, peat （PHA）, and leaf litter （LHA） as a function of contact time, pH, ion strength, and initial concentration was studied using the batch method. X-ray absorption spectroscopy （XAS） was used to examine the coordination environment of the Cu（ll） adsorbed by HA at a molecular level. Moreover, the chemical compositions of the isolated HA were characterized by elemental analysis and solid-state 13C nuclear magnetic resonance spectroscopy （NMR）. The kinetic data showed that the adsorption equilibrium can be achieved within 8 h. The adsorption kinetics followed the pseudo-second-order equation. The adsorption isotherms could be well fitted by the langmuir model, and the maximum adsorption capacities of Cu（ll） on CHA, PHA, and LHA were 229.4,210.4, and 197.7 mg g-1, respectively. The adsorption of Cu（Ⅱ） on HA increased with the increase in pH from 2 to 7, and maintained a high level at pH〉7. The adsorption of Cu（Ⅱ） was also strongly influenced by the low ionic strength of 0.01 to 0.2 mol L-1 NaNO3, but was weakly influenced by high ionic strength of 0.4 to 1 mol L-1 NaNO3. The Cu（Ⅱ） adsorption on HA may be mainly attributed to ion exchange and surface complexation. XAS results revealed that the binding site and oxidation state of Cu adsorbed on HA surface did not change at the initial Cu（Ⅱ） concentrations of 15 to 40 mg L 1. For all the Cu（Ⅱ） adsorption samples, each Cu atom was surrounded by 40/N atoms at a bond distance of 1.95 A in the first coordination shell. The presence of the higher Cu coordination shells proved that Cu（Ⅱ） was adsorbed via an inner-sphere covalent bond onto the HA surface. Among the three HA samples, the adsorption capacity and affinity of CHA for Cu（Ⅱ） was the greatest, followed by that of PHA and LHA. All the three HA samples exhibited similar types of elemental and functional groups, but different contents of elemental and functional gr

关键词： humic acid Cu(Ⅱ) adsorption organic material 13C NMR XAS

Additives strategies to improving cycling stability of li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan li Pengfei Huang Chunyu cui Xiaoyuan Ma li Chen Zekun li linhai li Yuhong Tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a liF and li3N-rich solid electrolyte interphase（SEI）.The liF component increases the robustness of SEI and suppresses the formation of li dendrites,while the li3N component facilitates the transportation and reaction kinetics of li *** a result,the li‖li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with liFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Electrolyte additive li dendrites li metal batteries liF and li3N-Rich electrode-electrolyte interphase liFePO4 cathode

Challenges in li-ion battery high-voltage technology and recent advances in high-voltage electrolytes

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Journal of Energy Chemistry 2024年第4期91卷 73-98页

作者： Jianguo liu Baohui li Jinghang Cao Xiao Xing Gan cui Shandong Key Laboratory of Oil&Gas Storage and Transportation Safety College of Pipeline and Civil EngineeringChina University of Petroleum(East China)Qingdao 266580ShandongChina

The electrolyte directly contacts the essential parts of a lithium-ion battery,and as a result,the electrochemical properties of the electrolyte have a significant impact on the voltage platform,charge discharge capacity,energy density,service life,and rate discharge *** raising the voltage at the charge/discharge plateau,the energy density of the battery is ***,this causes transition metal dissolution,irreversible phase changes of the cathode active material,and parasitic electrolyte oxidation *** article presents an overview of these concerns to provide a clear explanation of the issues involved in the development of electrolytes for high-voltage lithium-ion ***,solidstate electrolytes enable various applications and will likely have an impact on the development of batteries with high energy *** is necessary to improve the high-voltage performance of electrolytes by creating solvents with high thermal stabilities and high voltage resistance and additives with superior film forming performance,multifunctional capabilities,and stable lithium *** offer suggestions for the future development of high-energy lithium-ion batteries,we conclude by offering our own opinions and insights on the current development of lithium-ion batteries.

关键词： lithium-ion battery High voltage Electrolyte additive Solid electrolyte

基于R语言烟支、滤棒物理指标标偏和CPK标准值研究

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中国标准化 2024年第11期 270-274页

作者：段兴坤吕佳邓加睿谢勇李翠兰李庆松红云红河(烟草)集团会泽卷烟厂

为提高卷烟产品质量,实现卷烟物理指标的精准控制,对卷接工艺过程作出全面综合评判,以达到提质降耗,降本增量的目的。针对卷烟物理指标的过程能力指数和标准偏差通过R语言模拟数据生成,Phython语言绘制箱线图并以小于SD箱线图的四分之... 详细信息

为提高卷烟产品质量,实现卷烟物理指标的精准控制,对卷接工艺过程作出全面综合评判,以达到提质降耗,降本增量的目的。针对卷烟物理指标的过程能力指数和标准偏差通过R语言模拟数据生成,Phython语言绘制箱线图并以小于SD箱线图的四分之三作为SD值的判定标准,大于CPK箱线图的四分之三作为CPK值的判定标准。卷烟生产企业可截取一段时间的历史数据,并绘制箱线图,确定适合企业的SD值和CPK值判定界限。

关键词：卷烟产品质量标准偏差过程能力指数 R语言 Phython语言

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Missing microbes in infants and children in the COVID-19 pandemic:a study of 1,126 participants in Beijing,China

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Science China(life Sciences) 2024年第8期67卷 1739-1750页

作者： Jiejing Wang Yuejuan li Yu Mu Kefei Huang Danyi li Canhui lan Yutao cui Jun Wang CAS Key Lab for Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Beijing Dr.cuiYUTAO Clinic Beijing 100028China R-Institute Co.Ltd. Beijing 100011China

The COVID-19 pandemic has caused many fatalities worldwide and continues to affect the health of the recovered patients in the form of *** this study,we compared the gut microbiome of uninfected infants and children before the pandemic began(BEFORE cohort,n=906)to that of after the pandemic(AFTER cohort,n=220)to examine the potential impact of social distancing and life habit changes on infant/children gut *** on 16S rRNA sequencing,we found a significant change in microbiome composition after the pandemic,with Bacteroides enterotype increasing to 35.45%from 30.46%before the *** quantification indicated that the bacterial loads of seven keystone taxa decreased by 91.69%–19.58%.Quantitative microbiome profiling,used to enhance the resolution in detecting microbiome differences,revealed a greater explained variance of pandemic on microbiome compared to gender,as well as a significant decrease in bacterial loads in 15 of the 20 major *** random forest age-predictor indicated the gut microbiomes were less mature in the after-pandemic cohort than in the before-pandemic cohort in the children group(3–12 years old)and had features of a significantly younger age(average of 1.86 years).Lastly,body weight and height were significantly lower in the after-pandemic cohort than in the before-pandemic cohort in infants(<1 year of age),which was associated with a decrease in bacterial loads in the fecal microbiome.

关键词： gut microbiome COVID-19 pandemic quantitative microbiome profiling children health

Femtosecond laser fabrication of 3D vertically aligned micro-pore network on thick-film li_(4)Ti_(5)O_(12)electrode for high-performance lithium storage

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Journal of Energy Chemistry 2024年第8期95卷 250-262,I0006页

作者： Quansheng li Xiaofei Sun Xuesong Mei lingzhi Wang Minxing Yang Jianlei cui Wenjun Wang State Key Laboratory for Manufacturing System Engineering Xi'an Jiaotong UniversityXi'an 710049ShaanxiChina Shaanxi Key Laboratory of Intelligent Robots Xi'an Jiaotong UniversityXi'an 710049ShaanxiChina School of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710049ShaanxiChina

The development of energy storage devices with high energy density relies heavily on thick film electrodes,but it is challenging due to the limited ion transport kinetics inherent in thick ***,we report on the preparation of a directional vertical array of micro-porous transport networks on LTO electrodes using a femtosecond laser processing strategy,enabling directional ion rapid transport and achieving good electrochemical performance in thick film *** three-dimensional(3D)vertically aligned micro-pore networks are innovatively designed,and the structure,kinetics characteristics,and electrochemical performance of the prepared ion transport channels are analyzed and discussed by multiple characterization and testing ***,the rational mechanisms of electrode performance improvement are studied experimentally and simulated from two aspects of structural mechanics and transmission *** ion diffusion coefficient,rate performance at 60 C,and electrode interface area of the laser-optimized 60-15%micro-porous transport network electrodes increase by 25.2 times,2.2 times,and 2.15 times,respectively than those of untreated ***,the preparation of 3D micro-porous transport networks by femtosecond laser on ultra-thick electrodes is a feasible way to develop high-energy *** addition,the unique micro-porous transport network structure can be widely extended to design and explore other high-performance energy materials.

关键词： Femtosecond laser Micro-porous transport networks Laser processing Thick film electrodes Ion transport kinetics