检索结果-南通市图书馆

Microbial self-healing of cracks in cement-based materials and its influencing factors

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

Frontiers of Structural and Civil Engineering 2023年第11期17卷 1630-1642页

作者： xiaoniu yu Qiyong ZHANG Xuan ZHANG Mian LUO Jiangsu Key Laboratory of Construction Materials Southeast UniversityNanjing 211189China College of Engineering and Technology Southwest UniversityChongqing 400715China School of Civil Engineering and Architecture Jiangsu University of Science and TechnologyZhenjiang 212114China College of Civil Science and Engineering Yangzhou UniversityYangzhou 225127China

Cement-based materials are brittle and crack easily under natural conditions.Cracks can reduce service life because the transport of harmful substances can cause corrosion damage to the structures.This review discusses the feasibility of using microbial self-healing agents for crack healing.Tubular and spherical carriers can be used to load microbial self-healing agents and protect microbes,which prolongs the self-healing time.The area self-healing ratio,permeability,mechanical strength,precipitation depth method,numerical modeling,and ultrasonic method can be employed to identify the self-healing effect of cracks.Moreover,the self-healing mechanism is systematically analyzed.The results showed that microbial self-healing agents can repair cracks in cement-based materials in underground projects and dam gates.The difficulties and future development of self-healing cracks were analyzed.A microbial selfhealing agent was embedded in the cement-based material,which automatically repaired the developing cracks.With the development of intelligent building materials,self-healing cracks have become the focus of attention.

关键词： cement-based materials cracks microbial self-healing agent mechanism intelligent building materials

Optimization of Mineralization Curing System for Efficient and Safe Utilization of Steel Slag Wastes

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

Journal of Wuhan University of Technology(Materials Science) 2022年第4期37卷 595-602页

作者：伊海赫 ZHAN Qiwei yu xiaoniu School of Civil and Architectural Engineering Shandong University of TechnologyZibo 255000China School of Civil Engineering and Architecture Jiangsu University of Science and TechnologyZhenjiang 212003China Department of Civil and Environmental Engineering Nanyang Technological UniversitySingapore City 639798Singapore

The crystal structure and morphology of the mineralization products were studied by scanning electron microscopy(SEM)and X-ray diffraction(XRD),and the thermal properties were studied by thermogravimetric-differential scanning calorimetry(DSC)analysis.The changes of microorganism quantity and enzyme activity in pore solution with time were measured.The experimental results show that microorganism quantity and enzyme activity in pore solution reach the maximum at 50-60 h,mineralization curing begins at this time,the strength of microbial mineralized steel slag reaches the maximum.This study provides a good selection basis for selecting the optimum mineralization system for the production of microbial mineralized steel slag products.Bacterial mineralization can accelerate the rate of carbon sequestration in the mineralization process.The compressive strength of steel slag with 1.5% bacterial can reach up to 55.6 MPa.The microstructure and thermal properties of calcium carbonate precipitate induced by the enzymes of bacillus subtilis differs from the chemical precipitation in pore solution of steel slag.Through the analysis of the mineralized products of steel slag,the reaction rate of free calcium oxide and free magnesium oxide in steel slag after the addition of microorganisms is significantly increased,which improves the stability of steel slag as cementitious material.Meanwhile,the production of calcium carbonate,the main mineralized product,is significantly increased.

关键词： steel slag microorganism bio-mineralization enzyme activity curing system

Cementing mechanism of bio-phosphate cement

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2015年第6期58卷 1112-1117页

作者： yu xiaoniu QIAN ChunXiang WANG Xin School of Materials Science and Engineering Southeast University Research Institute of Green Construction Materials Southeast University

Cementing mechanism of bio-phosphate cement was investigated by Fourier transform infrared spectroscopy(FTIR), X-ray photoelectron spectroscopy(XPS), thermogravimetric-differential scanning calorimetry(TG-DSC) analysis and scanning electron microscopy(SEM). The results of FTIR and XPS show that Si-O bond and Si(2p) electron binding energy in sandstone cemented via chemical and microbiological methods are changed by the binding effects of barium hydrogen phosphate with quartz sand. Compared with barium hydrogen phosphate precipitated in solution, there were higher decomposition temperatures or melting points in sandstone. The FTIR, XPS, and TG-DSC results indicate that the microbial-induced and chemical precipitation of barium hydrogen phosphate can interact with quartz sand to generate van der Waals bond, which plays a role in the binding function between loose sand particles and barium hydrogen phosphate. SEM results show that barium hydrogen phosphate after chemical precipitation in sandstone has better dispersion than microbiological deposition. Therefore, barium hydrogen phosphate via chemical precipitation did not bind loose sand particles into sandstone.

关键词：微生物学方法骨水泥傅里叶变换红外光谱机制固井 X射线光电子能谱差示扫描量热法 TG-DSC

Experiments on and predictions about properties of sand bonded by microbe cement

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2016年第8期59卷 1186-1193页

作者： QIAN ChunXiang RONG Hui yu xiaoniu WANG Xin School of Materials Science and Engineering Southeast University Nanjing 211189 China Research Institute of Green Construction Materials Southeast University Nanjing 211189 China

新结合材料被介绍的微生物水泥。沙岩(0.05 m 直径， 0.5 m 高度) 并且沙堆(0.125 m 3) 被微生物水泥加入做整个身体。在对待的沙样品的相关性质的进化通过压缩力量和方解石内容被检验。结果显示 cemented 身体的结构是不一致的，方解... 详细信息

新结合材料被介绍的微生物水泥。沙岩(0.05 m 直径， 0.5 m 高度) 并且沙堆(0.125 m 3) 被微生物水泥加入做整个身体。在对待的沙样品的相关性质的进化通过压缩力量和方解石内容被检验。结果显示 cemented 身体的结构是不一致的，方解石内容从注射港口与距离减少，并且压缩力量也从注射港口与距离减少。另外，在测量方解石内容的进化和压缩力量被考虑微生物集中分发的一个数字模型总结。在为 0.5 m 高度沙岩的不同位置的方解石内容的数字结果类似于测试结果，和方解石内容和立方的沙堆是的 0.125 m 3 的压缩力量的试验性的结果类似于数字结果。当微生物水泥在实际工程工程被使用时，预言结果显示模拟应该成为一个重要增补工具。

关键词：水泥砂微生物粘结性能预测抗压强度试验生物水泥数值结果

Loose Sand Cemented by Microbial Cementitious Material:Composition,Microstructure and Mechanical Properties

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2021年第5期36卷 714-719页

作者：詹其伟 WANG Shugang LIU Baoya PAN Zhihong yu xiaoniu QIAN Chunxiang School of Civil Engineering and Architecture Jiangsu University of Science and TechnologyZhenjiang 212100China Guangdong Provincial Key Laboratory of Building Energy Efficiency and Application Technologies Guangzhou UniversityGuangzhou 510006China Training Base PLA Army Engineering UniversityXuzhou 221004China Department of Civil and Environmental Engineering Nanyang Technological UniversitySingapore City639798Singapore College of Materials Science and Engineering Southeast UniversityNanjing 211189China

Through the influence of the dosage of culture solution and calcium source on hardness and compressive strength of samples,the formulation of microbial cementitious materials was optimized and defined.The influence of temperature on composition,microstructure and mechanical properties of loose sand cemented by microbial cementitious material was compared and analyzed systematically.With the increase of temperature,the performance of loose sand was improved remarkably.Calcite with cementitious properties could be induced at higher temperatures,but not at lower temperatures.When the temperature was 30℃,loose sand cemented by microbial cementitious material had more calcite and more dense structure.Moreover,hardness and compressive strength were also superior.The wind tunnel test showed that the wind erosion resistance was improved obviously and the mass loss was lower at high temperature.Engineering properties of loose sand cemented by microbial cementitious material was measured integrally.Through comparative analysis,engineering properties of loose sand were basically unchanged,and there was no negative effect on the later period use of sand.

关键词： loose sand microbial cementitious material calcite microstructure mechanical properties

Loose Sand Particles Cemented by Chem/Bio-BaHPO_4 Powder

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2018年第5期33卷 1288-1292页

作者：於孝牛 QIAN Chunxiang College of Civil Engineering and Architecture Wenzhou University School of Materials Science and Engineering Southeast University

Bacillus subtilis was selected as the suitable microorganism,which could produce alkaline phosphatase and constantly hydrolyzed phosphate monoester in the mixture solution of bacteria with substrate,and then the PO4^3-was obtained.Bio-phosphate cement was prepared by alkaline earth element（Ba）ions reacting with PO4^3-in the mixture solution.Structure,size and thermal properties of the bio-phosphate cement were characterized by energy dispersive X-ray spectroscopy（EDS）,X-ray diffraction（XRD）,scanning electron microscopy（SEM）,and particle size analysis.The average crystallite sizes of chem-BaHPO4 and bio-BaHPO4corresponded to 11.99 and 24.13μm,respectively.Chem-BaHPO4 and bio-BaHPO4 were then adopted to bind loose sand particles.The results indicated that loose sand particles can be well cemented by the bio-BaHPO4powder into a bio-sandstone with a certain mechanical properties,and the average compressive strength of the bio-sandstones can be up to 0.83 MPa when the curing time was 14 d.Along with the method in future studies,there will be multiple new opportunities for engineering applications,for instance,the treatment of sandy soil foundation,remediation of heavy metals in contaminated soil,and so on.

关键词： Bacillus subtilis bio-phosphate cement X-ray techniques scanning electron microscope compressive strength

在线全文

学校读者我要写书评

暂无评论

基于生成对抗网络的地磁数据重建

地球物理学进展 2022年第3期37卷 989-997页

作者：于晓彤李夕海曾小牛刘继昊谭笑枫火箭军工程大学西安710025

实测地磁数据常因测区不规则导致数据存在空缺.针对地磁数据大面积缺失情况下,现有地磁数据重建方法精度不高的问题,本文提出了一种基于生成对抗网络的地磁数据重建方法.首先,利用生成对抗网络的博弈特性,在深度学习训练中不断优化地磁... 详细信息

实测地磁数据常因测区不规则导致数据存在空缺.针对地磁数据大面积缺失情况下,现有地磁数据重建方法精度不高的问题,本文提出了一种基于生成对抗网络的地磁数据重建方法.首先,利用生成对抗网络的博弈特性,在深度学习训练中不断优化地磁数据的生成网络和鉴别网络,得到最优的地磁数据生成模型,最后利用该模型可以实现对中心区域存在空缺的地磁数据进行重建.理论模型和实测地磁数据的对比实验结果表明,本文方法的重建精度高于经典的Kriging法、最小曲率法和基于凸集投影的方法;尤其在数据的结构性特征缺失较多的情况下,本文方法的地磁数据缺失部分重建结果的空间分布结构更加合理.

关键词：地磁数据重建深度学习生成对抗网络

在线全文

学校读者我要写书评

暂无评论

云南马关地区新生代碧玄岩中地幔包体研究

岩石学报 2006年第3期22卷 621-630页

作者：喻学惠莫宣学曾普胜朱德勤肖小牛中国地质大学地质过程与矿产资源国家重点实验室岩石圈构造深部过程及探测技术教育部重点实验室中国地质大学(北京)北京100083 云南财贸学院昆明650221

自晚新生代以来,由于受印度-亚洲板块碰撞和青藏高原整体快速抬升的影响,在云南省东南的马关地区发育了大量新生代碱性火山岩。其中有的火山岩中含有丰富的地幔包体。本文提供了马关八寨碧玄岩和钾玄岩的2个全岩化学分析资料,以及石榴... 详细信息

自晚新生代以来,由于受印度-亚洲板块碰撞和青藏高原整体快速抬升的影响,在云南省东南的马关地区发育了大量新生代碱性火山岩。其中有的火山岩中含有丰富的地幔包体。本文提供了马关八寨碧玄岩和钾玄岩的2个全岩化学分析资料,以及石榴二辉橄榄岩、尖晶二辉橄榄岩、石榴辉石岩和石榴二辉岩包体的全岩化学和电子探针分析结果,采用矿物温压计获得各种地幔包体的平衡温压条件,建立了本区地幔地温线,并与世界典型大地构造单元的地温线进行了对比。研究表明,石榴石二辉橄榄岩的平衡温压为1209℃～1230℃和2．13～2．93GPa,石榴石二辉岩为1034℃～1095℃和1．69～2．35GPa,尖晶石二辉橄榄岩的平衡温压为944℃～1072℃和1．46～2．74GPa,其对应的深度分别为69～93km、55～75km和48～87km。因此尖晶石二辉橄榄岩与石榴二辉橄榄岩和石榴二辉岩共存,其间没有截然的界限,而是一种过渡关系。由包体平衡温压建立的上地幔地温线与华北地区地温线一样,位于澳大利亚克拉通东缘地温线与碱性玄武岩省地温线之间,但本区地温线显著高于华北地温线,与本区具有高于华北地区的大地热流值相吻合。这证明各种辉石岩和橄榄岩包体来自地幔。根据平衡压力反演的包体起源深度推测,含石榴石的二辉橄榄岩可能来源于岩石圈底部或软流圈。基于上述研究,结合高原及滇西地区新生代钾质岩浆活动时空结构的研究成果,提出马关地区新生代碱性岩浆活动和地幔包体的成因,与印度-欧亚大陆俯冲碰撞诱发的软流圈横向地幔流的活动有关。

关键词：云南马关新生代火山岩地幔包体地幔地温线

闽中梅仙矿集区丁家山铅锌矿床成矿时代厘定及成矿物质来源:来自闪锌矿Rb-Sr同位素的证据

在线全文

学校读者我要写书评

暂无评论

地质通报 2022年第11期41卷 2026-2034页

作者：肖晓牛邢波余新明葛明慧秦新龙刘荣芳杜壮志江苏省地质局江苏南京210007 南京大学地球科学与工程学院江苏南京210093 福建金东矿业股份有限公司福建三明365101 福州大学紫金地质与矿业学院福建福州350108

丁家山铅锌矿床位于闽中梅仙矿集区西南部,矿体多呈层状、似层状和透镜状,产于中—新元古界马面山群龙北溪组的绿片岩和大理岩中。为查明该矿床的成矿时代,对该矿床中的主要矿石矿物闪锌矿开展了Rb-Sr同位素测年。8件闪锌矿样品构成的... 详细信息

丁家山铅锌矿床位于闽中梅仙矿集区西南部,矿体多呈层状、似层状和透镜状,产于中—新元古界马面山群龙北溪组的绿片岩和大理岩中。为查明该矿床的成矿时代,对该矿床中的主要矿石矿物闪锌矿开展了Rb-Sr同位素测年。8件闪锌矿样品构成的等时线年龄为143.1±3.2 Ma(MSWD=1.7),表明该矿床形成于燕山中期晚侏罗世。闪锌矿的锶同位素(初始比值为0.71434±0.00036)及前人的硫、铅同位素研究成果共同指示,丁家山矿床的成矿物质可能主要来源于下地壳的深源岩浆。综合分析认为,丁家山矿床形成于古太平洋板块向欧亚大陆板块俯冲-消减后的伸展引张环境背景下,是晚侏罗世到早白垩世期间的花岗岩体与中—新元古界的大理岩经接触交代后的矽卡岩型矿床。作为梅仙矿集区的典型铅锌矿床,丁家山矿床的成矿时代对区内其他铅锌矿床的成矿时代具有一定约束意义。

关键词：丁家山铅锌矿床 Rb-Sr同位素成矿时代梅仙矿集区闽中地区