检索结果-南通市图书馆

Effect of surfactant frequently used in soil flushing on oxygen mass transfer in micro-nano-bubble aeration system

Chinese Journal of Chemical Engineering 2024年第3期67卷 174-181页

作者： Mei Bai Zhibin liu Zhu liu Chenfei He Zhanhuang Fan Miaoxin Yuan Jiangsu key Laboratory of Urban Underground Engineering and Environmental Safety Southeast UniversityNanjing 211189China CECEP DADI(Hangzhou)Environmental Remediation Co. Ltd.Hangzhou 310020China

In-site soil flushing and aeration are the typical synergetic remediation technology for contaminated *** surfactant present in flushing solutions is bound to affect the aeration *** purpose of this study is to evaluate the effect of surfactant frequently used in soil flushing on the oxygen mass transfer in micro-nano-bubble(MNB)aeration ***,bio-surfactants and chemical surfactants were used to investigate their effects on Sauter mean diameter of bubble(dBS),gas holdup(ε),volumetric mass-transfer coefficient(kLa)and liquid-side mass-transfer coefficient(kL)in the MNB aeration ***,based upon the experimental results,the Sardeing's and Frossling's models were modified to describe the effect of surfactant on kL in the MNB *** results showed that,for the twenty aqueous surfactant solutions,with the increase in surfactant concentration,the value of dBS,kLa and kL decreased,while the value ofεand gas-liquid interfacial area(a)*** phenomena were mainly attributed to the synergistic effects of immobile bubble surface and the suppression of coalescence in the surfactant *** addition,with the presence of electric charge,MNBs in anionic surfactant solutions were smaller and higher in number than in non-ionic surfactant ***,the accumulation of surfactant on the gas-liquid interface was more conspicuous for small MNB,so the reduction of kL in anionic surfactant solutions was larger than that in non-ionic surfactant ***,the modified Frossling's model predicted the effect of surfactant on kL in MNB aeration system with reasonable accuracy.

关键词： Soil flushing Micro-nano-bubble aeration Bio-surfactant Mass transfer coefficient

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Performance Enhancement of Parabolic Trough Collector by Using Homogenizer and Spiral

引用

Journal of Thermal Science 2024年第2期33卷 658-674页

作者： LI Peijing liu Taixiu QIN Yuanlong ZHENG Zhimei ZHAO kai liu Qibin School of Energy Powerand Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Science Beijing100049China Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei230027China Research Institute of Science and Technology of China Three Gorges Group Corporation Beijing100038China

In conventional parabolic trough collectors(PTCs),sunlight is concentrated at the bottom of the absorber tube,resulting in a significant circumferential temperature gradient across the absorber tube,heat loss and thermal deformation,which affects the safety and thermal performance of *** this study,a new receiver with homogenizer and spiral(RHS) is proposed,achieving the optical and thermal synergy to ameliorate the thermal deformation of the absorber tube and enhance thermal efficiency.A plane structure homogenizer is designed to improve uniformity of the concentrated solar flux of absorber tube through second *** combination with the spiral,it improves the optical-thermal efficiency of the PTC by enhancing heat exchange between the fluid and the backlight side of the absorber *** performance of the collector is numerically studied by building a three-dimensional coupled light-thermal-structure *** results show that the thermal deformation of the RHS is reduced by more than 96% and the optical-thermal efficiency is improved by 1.2%-0.63% compared with conventional receivers(CRs) under the same inlet temperature *** proposed receiver is validated to be effective in reducing thermal deformation and improving optical-thermal efficiency.

关键词： parabolic trough collector homogenizer thermal deformation spiral

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Creep constitutive model considering nonlinear creep degradation of fractured rock

引用

International Journal of Mining Science and Technology 2024年第1期34卷 105-116页

作者： Wang Chunping liu Jianfeng Chen Liang liu Jian Wang Lu Liao Yilin Beijing Research Institute of Uranium Geology Beijing 100029China CAEA Innovation Center for Geological Disposal of High-Level Radioactive Waste Beijing 100029China State key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China School of Architecture and Civil Engineering Xihua UniversityChengdu 610039China

Stability analysis of underground constructions requires a model study of rock masses’ long-term performance. Creep tests under different stress conditions was conducted on intact granite and granite samples fractured at 30° and 45° angles. The experimental results indicate that the steady creep strain rates of intact and fractured rock present an exponential increase trend with the increase of stress level. A nonlinear creep model is developed based on the experimental results, in which the initial damage caused by fracture together with the damage caused by constant load have been taken into consideration. The fitting analysis results indicated that the model proposed is more accurate at identifying the full creep regions in fractured granite, especially the accelerated stage of creep deformation. The least-square fit error of the proposed creep model is significantly lower than that of Nishihara model by almost an order of magnitude. An analysis of the effects of elastic modulus, viscosity coefficient, and damage factors on fractured rock strain rate and creep strain is conducted. If no consideration is given to the effects of the damage, the proposed nonlinear creep model can degenerate into to the classical Nishihara model.

关键词： Fractured rock Damage Creep Beishan granite Geological disposal

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Disturbance failure mechanism of highly stressed rock in deep excavation:Current status and prospects

引用

International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 611-627页

作者： Tao Wang Weiwei Ye Liyuan liu kai liu Naisheng Jiang xianhui Feng School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China Department of Engineering Science University of OxfordParks RoadOxford OX13PJUK School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

This article reviews the current status on the dynamic behavior of highly stressed rocks under ***,the experimental apparatus,methods,and theories related to the disturbance dynamics of deep,high-stress rock are reviewed,followed by the introduction of scholars’research on deep rock deformation and failure from an energy ***,with a backdrop of highstress phenomena in deep hard rock,such as rock bursts and core disking,we delve into the current state of research on rock microstructure analysis and residual stresses from the perspective of studying the energy storage mechanisms in ***,the current state of research on the mechanical response and the energy dissipation of highly stressed rock formations is briefly ***,the insufficient aspects in the current research on the disturbance and failure mechanisms in deep,highly stressed rock formations are summarized,and prospects for future research are *** work provides new avenues for the research on the mechanical response and damage-fracture mechanisms of rocks under high-stress conditions.

关键词： deep rock with high stress highly stressed rock rock failure residual stress energy release

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Fatigue properties and damage constitutive model of salt rock based on CT scanning

引用

International Journal of Mining Science and Technology 2024年第2期34卷 245-259页

作者： Junbao Wang xiao liu Qiang Zhang xinrong liu Zhanping Song Shijin Feng College of Civil Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi key Lab of Geotechnical and Underground Space Engineering Xi’an 710055China School of Civil Engineering Chongqing UniversityChongqing 400045China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

To investigate the macroscopic fatigue properties and the mesoscopic pore evolution characteristics of salt rock under cyclic loading,fatigue tests under different upper-limit stresses were carried out on salt rock,and the mesoscopic pore structures of salt rock before and after fatigue tests and under different cycle numbers were measured using CT scanning *** on the test results,the effects of the cycle number and the upper-limit stress on the evolution of cracks,pore morphology,pore number,pore volume,pore size,plane porosity,and volume porosity of salt rock were *** failure path of salt rock specimens under cyclic loading was analyzed using the distribution law of plane *** damage variable of salt rock under cyclic loading was defined on basis of the variation of volume porosity with cycle *** order to describe the fatigue deformation behavior of salt rock under cyclic loading,the nonlinear Burgers damage constitutive model was further *** results show that the model established can better reflect the whole development process of fatigue deformation of salt rock under cyclic loading.

关键词： Salt rock Cyclic loading CT scanning Mesoscopic pore evolution Constitutive model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Migration Networks Pattern of China’s Floating Population from the Perspective of Complex Network

引用

Chinese Geographical Science 2024年第2期34卷 327-341页

作者： liu Wangbao CHEN Ranran College of Geography Science South China Normal UniversityGuangzhou 510631China

Since China’s reform and opening-up,the growing disparity between urban and rural areas and regions has led to massive *** China’s Rural Revitalization Strategy and the industrial transfer from the eastern coastal areas to the inland,the migration direction and pattern of the floating population have undergone certain *** the 2017 China Migrants Dynamic Survey(CMDS),excluding Hong kong,Macao,and Taiwan regions of China,organized by China’s National Health Commission,the relationship matrix of the floating population is constructed according to the inflow place of the interviewees and their outflow place(the location of the registered residence)in the questionnaire *** then apply the complex network model to analyze the migration direction and network pattern of China’s floating population from the city *** migration network shows an obvious hierarchical *** first-,second-,third-and fourth-tier distribution cities are municipalities directly under the central government,provincial capital cities,major cities in the central and western regions and ordinary cities in all provinces,*** migration trend is from the central and western regions to the eastern coastal *** migration network has‘small world’characteristics,forming nine *** shows that most node cities in the same community are closely linked and geographically close,indicating that the migration network of floating population is still affected by geographical *** the urban-rural and regional differences will promote the rational distribution this *** is necessary to strengthen the reform of the registered residence system,so that the floating population can enjoy urban public services comparable to other populations,and allow migrants to live and work in peace.

关键词： complex network floating population migration network spatial pattern community structure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Review of dynamics and active control of large-scale space membrane antenna

引用

Astrodynamics 2024年第1期8卷 1-26页

作者： xiang liu Guoping Cai Department of Engineering Mechanics MOE Key Laboratory of HydrodynamicsChongqing Research InstituteShanghai Jiao Tong UniversityShanghai200240China

Large-scale space membrane antennas have significant potential in satellite communication,space-based early warning,and Earth *** of their large size and high flexibility,the dynamic analysis and control of membrane antenna are *** maintain the working performance of the antenna,the pointing and surface accuracies must be strictly ***,the accurate dynamic modeling and effective active control of large-scale space membrane antennas have great theoretical significance and practical value,and have attracted considerable interest in recent *** paper reviews the dynamics and active control of large-scale space membrane ***,the development and status of large-scale space membrane antennas are ***,the key problems in the dynamics and active control of large membrane antennas,including the dynamics of wrinkled membranes,large-amplitude nonlinear vibration,nonlinear model reduction,rigid-flexible-thermal coupling dynamic modeling,on-orbit modal parameter identification,active vibration control,and wave-based vibration control,are discussed in ***,the research outlook and future trends are presented.

关键词： large-scale space membrane antenna dynamicmodeling active control

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Predictability of the upper ocean heat content in a Community Earth System Model ensemble prediction system

引用

Acta Oceanologica Sinica 2024年第1期43卷 1-10页

作者： Ting liu Wenxiu Zhong State key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China School of Atmospheric Sciences Sun Yat-Sen UniversityZhuhai 519082China

Upper ocean heat content(OHC)has been widely recognized as a crucial precursor to high-impact climate variability,especially for that being indispensable to the long-term memory of the *** the predictability of OHC using state-of-the-art climate models is invaluable for improving and advancing climate *** developed retrospective forecast experiments,based on a Community Earth System Model ensemble prediction system,offer a great opportunity to comprehensively explore OHC *** results indicate that the skill of actual OHC predictions varies across different oceans and diminishes as the lead time of prediction *** spatial distribution of the actual prediction skill closely resembles the corresponding persistence skill,indicating that the persistence of OHC serves as the primary predictive signal for its *** decline in actual prediction skill is more pronounced in the Indian and Atlantic oceans than in the Pacific Ocean,particularly within tropical ***,notable seasonal variations in the actual prediction skills across different oceans align well with the phase-locking features of OHC *** potential predictability of OHC generally surpasses the actual prediction skill at all lead times,highlighting significant room for improvement in current OHC predictions,especially for the North Indian Ocean and the Atlantic *** such improvements necessitates a collaborative effort to enhance the quality of ocean observations,develop effective data assimilation methods,and reduce model bias.

关键词： ocean heat content prediction skill retrospective forecast experiment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optimizing electronic structure of Mo_(2)TiC_(2)T_(x) Mxene through Nb doping for enhanced electrochemical performance

引用

Nano Research 2024年第8期17卷 7174-7181页

作者： Jingyuan Zhao Wenzheng Yan Zhaoxi liu xiaobin liu Yapeng Tian xinwei Cui Henan Institute of Advanced Technology College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450003China College of Physics and Electronic Information Engineering Guilin University of TechnologyGuilin 514004China

Mxene is a promising electrode material for both high volumetric capacitance and high-rate performance in ***,the current study has mainly focused on the monometallic element Ti_(3)C_(2)T_(x) Mxene until now,while the bimetallic and multimetallic Mxene have received comparatively less *** this work,we demonstrate that the electronic structure of the Mo_(2)TiC_(2)T_(x) Mxene could be regulated by fine-tuning the content of doped Nb *** enhanced electron cloud density of surface–O termination and the electron spin of the Mo atoms in the Mo_(2)TiC_(2)T_(x) Mxene,leads to the boost of electric double-layer capacitor(EDLC)and improvement of *** a consequence,the electrochemical performance of Nb-doped Mo_(2)TiC_(2)T_(x) Mxene(Nb-0.3-Mxene)demonstrates a capacitance of 398 F·cm^(−3),roughly doubling that of the pristine Mo_(2)TiC_(2)T_(x) Mxene electrode at 197 F·cm^(−3) in the 3 M H_(2)SO_(4) *** the same time,the Nb-0.3-Mxene could even maintain a capacitance of 82.75% at 200 mV·s−1,with high cyclic stability for 19,000 cycles at 10 A·g−***,Nb-0.3-Mxene-based hybrid supercapacitors deliver a remarkable volumetric energy density of 48.1 W·h·L^(−1)at 230.7 W·L^(−1),and 34.4 W·h·L^(−1)at a high power density of 82.6 kW·L^(−1).There exists a balance between the volumetric capacitance and rate performance with different ratios of Nb atoms in the Nb-doped Mxene due to the strong interaction between the Nb-doped Mxene and the intercalated ***,optimizing the electronic structure of Mxene through heteroatom doping is of great potential for enhanced supercapacitor performance.

关键词： niobium doping electronic structure Mo_(2)TiC_(2)T_(x)Mxene electron spin rate performance volumetric capacitance

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A real-world study of the differences in Traditional Chinese Medicine diagnosis and treatment rules for coronavirus disease 2019 between Northern and Southern China

引用

Journal of Traditional Chinese Medicine 2024年第4期44卷 822-829页

作者： SU Rui SU Youzhu WANG Shuo FAN Jie liu Qingquan liu Mifeng Department of infectious diseases Capital Medical University Beijing Hospital of Traditional Chinese MedicineBeijing 100010China

OBJECTIVE:To explore the differences in Traditional Chinese Medicine(TCM)diagnosis and treatment rules for coronavirus disease 2019(COVID-19)between Northern and Southern China based on the real-world data from 982 COVID-19 ***:All consecutive cases of COVID-19 admitted to the TCM department of designated COVID-19 hospitals in eight provinces and cities were retrospectively *** were divided into a Northern and a Southern group according to the location of the admitting *** symptoms,syndrome elements,syndrome distribution and herbal treatments were *** core prescriptions were extracted using the multiscale backbone-based network comparison algorithm(msbNC).RESULTS:The distribution of syndrome elements showed that dampness was common in Northern and Southern China,wind and heat were more often present in the South,while fire toxin and spleen deficiency were more often encountered in the *** distribution of syndromes showed that the South was dominated by heat dampness accumulating in the lung(55.69%),while the North was dominated by dampness-toxin stagnating in the lung(44.90%).The results of core prescription mining showed that dispelling dampness,dispersing wind,clearing heat and strengthening spleen were the common treatment methods in Northern and Southern *** mild cases,Jinyinhua(Flos Lonicerae)and Lianqiao(Fructus Forsythiae Suspensae)were often used in the South to clear heat and relieve exterior symptoms,while Chaihu(Radix Bupleuri Chinensis)and Huangqin(Radix Scutellariae Baicalensis)were often used in the North to relieve muscles by expelling *** moderate cases,Chaihu(Radix Bupleuri Chinensis),Qinghao(Herba Artemisiae Annuae),and Shigao(Gypsum Fibrosum)were often used to clear heat of Tri-jiao Channel and stomach in the South,while Fuling(Poria),Chenpi(Pericarpium Citri Reticulatae),and Dangshen(Radix Codonopsis)were often used to invigorate spleen and remove dampness in the *** severe cases

关键词： COVID-19 medicine,Chinese traditional North-South difference core prescription syndrome retrospective studies

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：