检索结果-南通市图书馆

Failure mechanism and safety control technology of a composite strata roadway in deep and soft rock masses:a case study

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2024年第7期21卷 2427-2444页

作者： ZHAO Chengwei ZHOU Hui SUN Xiaoming zhang Yong MIAO Chengyu WANG jian State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China

The construction of coal mines often encounters deep composite soft rock roadways,which is characterized by significant deformation and poor *** deeply study the failure mechanism and large deformation challenges of a composite strata roadway in deep and soft rock masses,a numerical model of 3DEC tetrahedral blocks was established based on the method of rock quality designation(RQD).The results showed that original support cannot prevent asymmetric failure and large deformation due to the adverse geological environment and unsuitable support *** to the failure characteristics,a coupling support of“NPR bolt/cable+mesh+shotcrete+steel pipe”was proposed to control the stability of the surrounding *** excellent mechanical properties of large deformation(approximately 400 mm)and high constant resistance force(bolt with 180 k N;cable with 350 k N)were evaluated by the tensile *** numerical results showed that the maximum deformation was minimized to 243 mm,and the bearing capacity of the surrounding rock of the roadway was *** field test results showed that the maximum deformation of the surrounding rock was 210 mm,and the forces of the NPR bolt and cable were stable at approximately 180 k N and 350 k N,*** demonstrated the effectiveness of the coupling support with the NPR bolt and cable,which could be a guiding significance for the safety control of large deformation and failure in deep composite soft rock roadways.

关键词： 3DEC Composite strata roadway Soft rock NPR bolt and cable Asymmetric large deformation

Hydrothermal Synthesis of Ce-doped ZnO Heterojunction Supported on Carbon Nanofibers with High Visible Light Photocatalytic Activity

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2021年第3期37卷 565-570页

作者： jian Shaoju TIAN Zhiwei zhang Kaiyin DUAN Gaigai YANG Weisen jianG Shaohua Fujian Key Laboratory of Eco-Industrial Green Technology College of Ecology and Resources EngineeringWuyi UniversityWuyishan354300P.R.China jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Materials Science and EngineeringNanjing Forestry UniversityNanjing210037P.R.China College of Mechanical and Electrical Engineering Wuyi UniversityWuyishan 354300P.R.China

Ce/ZnO decorated carbon nanofibers(CNFs)heteroarchitectures(Ce/ZnO/CNFs)have been synthesized using electrospinning technique followed hydrothermal method,which have a high visible light photocatalytic *** samples were characterized by means of SEM,FTIR and *** photocatalytic performance of Ce/ZnO/CNFs was tested with the methylene blue in the presence of visible light *** this work,we have analyzed the effects of Ce doping amount,initial methylene blue(MB)concentration and dosage of Ce/ZnO/CNFs on photocatalytic efficiency of the *** results showed that the photocatalyst containing 1.0%Ce in molarity(CZC1)obtained by autoclaving at 150℃ has the best photocatalytic degradation of MB than other as-synthesized ***/ZnO/CNFs catalysts exhibit a good stability and reusability,which would be an economical and environmentally friendly photocatalyst for various practical applications.

关键词： Photocatalysis Electrospinning Visible light Degradation Carbon nanofiber

Quaternary biogenic opal records in the South China Sea: Linkages to East Asian monsoon, global ice volume and orbital forcing

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

Science China Earth Sciences 2007年第5期50卷 710-724页

作者： WANG Rujian jian ZhiMin XIAO WenShen TIAN Jun LI jianRu CHEN RongHua zheng YuLong CHEN jianFang State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China

Particulate fluxes investigated in the central South China Sea (SCS) during 1993―1996 indicate that opal flux can be used to show primary productivity change, which provides a foundation for tracing the evolutionary relationship between the surface productivity and East Asian monsoon in the SCS during the late Quaternary glacial and interglacial periods. Based on the studies of opal % and their mass accumulation rates (MAR) at the six sites recovered from the SCS during the “Resolution” ODP Leg 184 and “Sonne” 95 cruise of the Sino-Germany cooperation, opal % and their MARs increased evidently in the northern sites since 470―900 ka, and they enhanced and reduced, respectively, during the glacial and interglacial periods. Whereas they increased obviously in the southern sites since 420―450 ka, and they augmented and declined, respectively, during the interglacial and glacial periods. The vari- ability in opal % and their MARs in the late Quaternary glacial cyclicity indicate the “seesaw” pattern of surface productivity in the SCS. The winter monsoon intensified during the glacial periods, surface productivity increased and decreased, respectively, in the northern and southern SCS. The summer monsoon strengthened during the interglacial periods, surface productivity increased and decreased, respectively, in the southern and northern SCS. The cross spectral analyses between the opal % in the northern and southern SCS during the Quaternary and global ice volume (δ 18O) and orbital forcing (ETP) indicate that the East Asian winter and summer monsoons could be ascribed to the different drive mechanisms. On the orbital time scale, the global ice volume change could be a dominant factor for the winter monsoon intension and temporal variations. As compared with the winter monsoon, the correlative summer solar radiation with the obliquity and precession in the Northern Hemisphere could be a mostly controlling factor for the summer monsoon intension and temporal variations.

关键词： biogenic opal surface productivity East Asian monsoon global ice volume orbital forcing ODP Leg 184 Quaternary South China Sea

Jisuikang, a Chinese herbal formula, increases neurotrophic factor expression and promotes the recovery of neurological function after spinal cord injury

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2017年第9期12卷 1519-1528页

作者： Yang Guo Yong Ma Ya-lan Pan Su-yang zheng jian-wei Wang Gui-cheng Huang Institute of Traumatology & Orthopedics and Laboratory of New Techniques of Restoration & Reconstruction of Orthopedics and Traumatology Nanjing University of Chinese Medicine Department of Traumatology & Orthopedics Affiliated Hospital of Nanjing University of Chinese Medicine Department of Traumatology & Orthopedics Wuxi Hospital of Traditional Chinese Medicine Affiliated to Nanjing University of Chinese Medicine

The Chinese medicine compound, ]isuikang, can promote recovery of neurological function by inhibiting lipid peroxidation, scavenging oxygen free radicals, and effectively improving the local microenvironment after spinal cord injury. However, the mechanism remains unclear. Thus, we established a rat model of acute spinal cord injury using a modified version of Allen＇s method. Jisuikang （50, 25, and 12.5 g/kg/d） and prednis- olone were administered 30 minutes after anesthesia. Basso, Beattie, and Bresnahan locomotor scale scores and the oblique board test showed improved motor function recovery in the prednisone group and moderate-dose Jisuikang group compared with the other groups at 3-7 days post-injury. The rats in the moderate-dose Jisuikang group recovered best at 14 days post-injury. Hematoxylin-eosin staining and transmis- sion electron microscopy showed that the survival rate of neurons in treatment groups increased after 3-7 days of administration. Further, the structure of neurons and glial cells was more distinct, especially in prednisolone and moderate-dose Jisuikang groups. Western blot assay and immunohistochemistry showed that expression of brain-derived neurotrophic factor （BDNF） in injured segments was maintained at a high level after 7-14 days of treatment. In contrast, expression of nerve growth factor （NGF） was down-regulated at 7 days after spinal cord injury. Re- al-time fluorescence quantitative polymerase chain reaction showed that expression of BDNF and NGF mRNA was induced in injured segments by prednisolone and Jisuikang. At 3-7 days after injury, the effect of prednisolone was greater, while 14 days after injury, the effect of moder- ate-dose Jisuikang was greater. These results confirm that Jisuikang can upregulate BDNF and NGF expression for a prolonged period after spinal cord injury and promote repair of acute spinal cord injury, with its effect being similar to prednisolone.

关键词： nerve regeneration spinal cord injury Jisuikang Chinese medicine prednisolone microenvironment axon regeneration secondary changes neuronal apoptosis brain-derived neurotrophic factor nerve growth factor neural regeneration

Adsorption removal of sulfamethoxazole from water using UiO-66 and UiO-66-BC composites

在线全文

学校读者我要写书评

暂无评论

Particuology 2022年第3期20卷 71-78页

作者： Jinbo Ouyang jian Chen Shaoqing Ma Xiaohong Xing Limin Zhou Zhirong Liu Chuntao zhang jiangxi Province Key Laboratory of Synthetic Chemistry East China University of TechnologyNanchang 330013China School of Chemistry and Chemical Engineering Wuhan University of Science and TechnologyWuhan 430081China

The adsorption removal of anti-inflammatory drugs from water by diverse materials has drawn great *** study investigated the adsorption of sulfamethoxazole(SMX)by two types of materials,UiO-66 and UiO-66-BC *** porous MOF composites with functional groups were synthesized by combining UiO-66 with corncob-based biochar at different molar *** results showed that macroporosity of UiO-66-BC composites was increased by increasing the ratio of *** was found that UiO-66-BC composites displayed highly improved adsorption performance of SMX relative to pristine ***-66-BC(5%)had the highest SMX adsorption capacity,about 2.4 times those of pristine *** was the high surface area of UiO-66 and redundant functional groups of biochar that increased the adsorption performance of ***,UiO-66-BC can be reused and displayed the competitive adsorption efficiency after successive adsorption,which made it a potential adsorbent for the removal of SMX from water.

关键词： Adsorption UiO-66 Biochar Sulfamethoxazole

Symmetrical Independence Tests for Two Random Vectors with Arbitrary Dimensional Graphs

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

Acta Mathematica Sinica,English Series 2022年第4期38卷 662-682页

作者： Jia Min LIU Gao Rong LI jian Qiang zhang Wang Li XU Center for Applied Statistics Renmin University of ChinaBeijing 100872P.R.China School of Statistics Beijing Normal UniversityBeijing 100875P.R.China

Test of independence between random vectors X and Y is an essential task in statistical *** type of testing methods is based on the minimal spanning tree of variables X and *** main idea is to generate the minimal spanning tree for one random vector X,and for each edges in minimal spanning tree,the corresponding rank number can be calculated based on another random vector *** resulting test statistics are constructed by these rank ***,the existed statistics are not symmetrical tests about the random vectors X and Y such that the power performance from minimal spanning tree of X is not the same as that from minimal spanning tree of *** addition,the conclusion from minimal spanning tree of X might conflict with that from minimal spanning tree of *** order to solve these problems,we propose several symmetrical independence tests for X and *** exact distributions of test statistics are investigated when the sample size is ***,we study the asymptotic properties of the statistics.A permutation method is introduced for getting critical values of the *** with the existing methods,our proposed methods are more efficient demonstrated by numerical analysis.

关键词： Exact distribution minimal spanning tree asymptotic distribution symmetrical independence test

Texture Evolution and Dynamic Recrystallization of Zr-1Sn-0.3Nb-0.3Fe-0.1Cr Alloy During Hot Rolling

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 215-224页

作者： jian Xun Gaoyong Lin Huiqun Liu Siyu Zhao Jing Chen Xun Dai Ruiqian zhang School of Materials Science and Engineering Central South UniversityChangsha 410083China Key Lab of Nonferrous Materials Ministry of EducationCentral South UniversityChangsha 410083China Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu 610213China

In the present work,the sheets of Zr-1Sn-0.3Nb-0.3Fe-0.1Cr alloy were hot rolled with different reductions(10%,30%,50%,and 60%) at 1023 K and 1073 *** micro structure evolutions including grain micro structure,texture,and dislocation were investigated,using electron backscattering diffraction and transmission electron *** results showed that dislocation slip,twinning,and dynamic recrystallization(DRX) were the main deformation *** was found to be promoted by larger reduction and higher rolling *** predominant texture formed during hot rolling was basal //ND,whose intensity reached peak value after 30% reduction hot *** the intensity of DRX texture //ND and//ND increased with increasing reduction and *** study provided an effective way to tailor the texture and microstructure of the alloy,for optimizing process parameters.

关键词： Zr–1Sn–0.3Nb–0.3Fe–0.1Cr alloy Hot rolling Texture evolution Recrystallization

Molecular identification, expression and function analysis of peroxidasin in Chilo suppressalis

在线全文

学校读者我要写书评

暂无评论

Insect Science 2020年第6期27卷 1173-1185页

作者： Chun-Ping Ma Zi-Mu Guo Feng-Li zhang jian-Ya Su Key Laboratory of Integrated Management of Crop Diseases and Pests(Ministry of Education) College of Plant ProtectionNanjing Agricultural UniversityNanjingChina

Peroxidasin plays a unique role in the formation and stability of extracellular matrix(ECM)in the animal kingdom;however,it was only characterized in Diptera,not in other insect *** this study peroxidasin(CsPxc/)was first identified and characterized from Chilo suppressalis,a lepidopteran *** complementary DNA with a 4080 bp open reading frame encodes a peptide of 1359 amino acids;the derived amino acid sequence of CsPxd harbors the typical structural characteristics of peroxidasin family in heme-peroxidase superfamily,including the signal peptide at N-terminal,leucine-rich repeat domain,Ig-loop motifs and peroxidase domain,signifying the extracellular location of protein and the involvement in ECM *** expression reveals CsPxd protein displays peroxidase activity on H2O2,justifying the membership of *** analysis shows the monophyletic evolution pattern of peroxidasin in insect phyle,and moreover only one peroxidasin is present in each species of insects,suggesting its evolutionary conservation on *** messenger RNA is mainly expressed in egg and the final instar larvae *** of peroxidasin double-stranded RNA into the final instar larvae impacts the cuticle sclerotization during the metamorphosis from larvae to pupa,and eventually lead to lethality of larvae and *** results suggest the presence of collagen crosslink in chorion and cuticle of insects,and indicate peroxidasin plays a role in the development of chorion and cuticle;furthermore peroxidasin might be the one of potential target genes for pest control using RNA interference.

关键词： Chilo suppressalis cuticle sclerotization peroxidase peroxidasin RNA interference

LiPAA with Short-chain Anion Facilitating Li_(2)S_(x)(x≤4)Reduction in Lean-electrolyte Lithium–sulfur Battery

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

Energy & Environmental Materials 2022年第3期5卷 877-882页

作者： Jizong zhang Mingming Chen Yu Si jian Guo Tianli Wu Chengyang Wang Xiaolei Wang Key Laboratory for Green Chemical Technology of MOE School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin UniversityTianjin 300072China Department of Chemical and Materials Engineering University of AlbertaEdmonton AB T6G 1H9Canada

Lean electrolyte usage in lithium–sulfur battery(LSB)meets the demand of the high energy ***,lean condition makes the electrolyte-related interface discrete,leading to retardation of ion transfer that depends on ***,electrochemical reactions face ***,lithium polyacrylate acid(LiPAA)with short-chain anions(molecular weight of 2000)is introduced into the *** of the polysulfide(PS)-philic instinct of the short-chain PAA anions,short-chain PS is captured inside of the *** addition,LiPAA supplies Li^(+)to the short-chain PS *** strong interaction between Li_(2)S_(4)and LiPAA effectively decreases Li_(2)S_(4)migration to the anode during *** a sense,the ion mass transfer pattern is thus changed comparing to traditional long-way mode between cathode and *** intermittent titration technique(GITT)proves that the interfacial reaction resistance is greatly decreased in the region where Li_(2)S_(x)(x≤4)reduction contributes *** the same time,the reversibility of electrochemical reduction/oxidation is *** to the accelerated Li_(2)S_(x)(x≤4)reduction,Li implanting of only 0.3 wt.%plus O introduction up to 1.4 wt.%enables the LSB perform well even with 1/4 of regular electrolyte dosage(5μL mg^(-1))and high-sulfur loading(4.2 mg cm^(-2)),increasing its rate capacity C_(0.8/0.5)from 52.6%(without the LiPAA)to 92.3%(with the LiP AA)as well as a capacity of 518.7 mAh g^(-1)after 400 cycles at 0.8 mA cm^(-2).

关键词： lean electrolyte polysulfides targeting transfer mass transfer interfacial reaction