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Case study of a driven pile foundation in diatomaceous soil.I:Site characterization and engineering properties 被引量:1
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作者 Jiayao Wang Ehsan Yazdani T.Matthew Evans 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第2期431-445,共15页
Diatomaceous soils are comprised of the silica frustules of diatom microalgae that are present in marine and lacustrine environments throughout the world.Owing to their unique origin,diatomaceous soils are typically c... Diatomaceous soils are comprised of the silica frustules of diatom microalgae that are present in marine and lacustrine environments throughout the world.Owing to their unique origin,diatomaceous soils are typically characterized by high intraparticle porosity,complex particle shapes,and uniform mineralogy,causing them to exhibit atypical physical and engineering behaviors.A substantial deposit of diatomaceous silt was observed during site exploration for construction of the Buck Creek Bridge on OR140 near Klamath Falls,OR,USA.A comprehensive laboratory and in situ testing program indicated that the diatomaceous soil possessed“non-textbook”engineering properties.Specifically,tested samples had high liquid limits(≈100%-140%)with natural water contents at or near the liquid limit.Geologically,the soil is expected to be normally consolidated,yet high apparent overconsolidation ratios(OCR)(≈15-40)were observed both in oedometric consolidation tests and through cone penetration test(CPT)correlations.Standard penetration test(SPT)results show a corrected standard penetration resistance consistent with a medium-dense sand(i.e.(N1)_(60)≈25).CPT results include corrected tip resistances(qt)of approximately 7-10 MPa and excess pore pressures(u_(2))of up to 4 MPa.In CPT dissipation tests,pore water pressures(PWPs)returned to hydrostatic pressure in less than 1 h.In this work,we synthesize these seemingly disparate material properties in an attempt to infer appropriate engineering properties for the diatomaceous deposit at the Buck Creek Bridge and attempt to provide insight into the underlying reasons for the observed behavior. 展开更多
关键词 Diatomaceous soil Problematic soil site characterization Laboratory testing
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Spectroscopy framework and review of characterization of energy resource sites
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作者 C.Tohm T.Bheemasetti P.Diwakar 《Energy Geoscience》 2022年第2期147-159,共13页
Site characterization and rapid reliable identification of energy resources play a key role for future efficient energy production.Over the last several decades,many laboratory and in-situ techniques were developed to... Site characterization and rapid reliable identification of energy resources play a key role for future efficient energy production.Over the last several decades,many laboratory and in-situ techniques were developed to qualitatively and quantitatively characterize the sites and minerals.Despite the advancements,there are still many challenges associated with exploration,rapid detection,and spatial interpolation of the energy resources within a site.Spectroscopy techniques offer solutions to the current ongoing efforts on site characterization,exploration and collection of resources,quality control monitoring during production,and reclamation of the production sites due to environmental contamination.Spectral analysis has shown great promise in providing in-situ measurements that are comparable to arduous laboratory physio-chemical analysis.Spectroscopy is a fairly new technology in some sectors and has seen limited use but has shown great potential in exceeding the minimum standards implemented.This paper presents review of the current spectroscopy techniques that have been used in the agriculture,landfill,nuclear power,mining,and ground contamination industries with respect to the production of energy.A general overview of how spectral analysis techniques are being used to benefit each of these sectors along with some of the drawbacks associated with each is presented.Three frameworks including basic process,operation flowchart,minimum number of tests to be performed,and information on spatial interpolation analysis are presented.These frameworks along with the basic processes can be implemented for characterization of energy resource sites。 展开更多
关键词 SPECTROSCOPY Energy resources Spectral analysis In-situ testing site characterization
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CHARACTERIZATION OF COBALT SITES IN REDUCED Co-Mo/Al_2O_3 AND Ru-Co-Mo/Al_2O_3 CATALYSTS
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作者 Fend Shou XIAO (Department of Chemistry,Jilin University,Changchun 130023)Qin XIN Xie Xian GUO (National Laboratory for Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第7期581-582,共2页
The two Co sites are well characterized in reduced Co-Mo/Al_2O_3 and Ru-Co- Mo/Al_2O_3 by new bands at 1895 and 1880 cm^(-1)in the IR spectra due to NO adsorption.
关键词 Mo Co CO characterIZATION OF COBALT siteS IN REDUCED Co-Mo/Al2O3 AND Ru-Co-Mo/Al2O3 CATALYSTS AL RU
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Spectroscopic Characterization of Staphylococcal Nuclease Mutants with Tryptophan at Internal Sites
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作者 高光宇 李渝 +3 位作者 王伟 仲冬平 王树峰 龚旗煌 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期151-155,共5页
Tryptophan (Trp) is an intrinsic fluorescent probe for detecting the site-specified dynamics inside/outside protein. It is found that the Trp can easily be inserted in desired sites of protein, which affects the int... Tryptophan (Trp) is an intrinsic fluorescent probe for detecting the site-specified dynamics inside/outside protein. It is found that the Trp can easily be inserted in desired sites of protein, which affects the integrity of the overall structure. To evaluate this effect, we design thirteen double point mutants of staphylococcal nuclease, each of which has a single Trp residue planted at an internal site. The studies on Trp fluorescence, ANS-binding fluorescence, far- and near-UV CD spectra, and enzymatic activity are carried out. It is found that the mutation at the hydrophobic core of protein generates molten globular state conformation, which is a loose structure compared to their original compactness in wild type (WT). Its enzyme activity and surface hydrophobicity are also affected. The studies show that by proper site designing and external binding, Trp mutagenesis is a suitable method for carrying out the study on site specified dynamics of proteins. 展开更多
关键词 WT Spectroscopic characterization of Staphylococcal Nuclease Mutants with Tryptophan at Internal sites ANS
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Evaluation of Unknown Groundwater Contaminant Sources Characterization Efficiency under Hydrogeologic Uncertainty in an Experimental Aquifer Site by Utilizing Surrogate Models
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作者 Shahrbanoo Hazrati-Yadkoori Bithin Datta 《Journal of Water Resource and Protection》 2017年第13期1612-1633,共22页
Characterization of unknown groundwater contaminant sources is an important but difficult step in effective groundwater management. The difficulties arise mainly due to the time of contaminant detection which usually ... Characterization of unknown groundwater contaminant sources is an important but difficult step in effective groundwater management. The difficulties arise mainly due to the time of contaminant detection which usually happens a long time after the start of contaminant source(s) activities. Usually, limited information is available which also can be erroneous. This study utilizes Self-Organizing Map (SOM) and Gaussian Process Regression (GPR) algorithms to develop surrogate models that can approximate the complex flow and transport processes in a contaminated aquifer. The important feature of these developed surrogate models is that unlike the previous methods, they can be applied independently of any linked optimization model solution for characterizing of unknown groundwater contaminant sources. The performance of the developed surrogate models is evaluated for source characterization in an experimental contaminated aquifer site within the heterogeneous sand aquifer, located at the Botany Basin, New South Wales, Australia. In this study, the measured contaminant concentrations and hydraulic conductivity values are assumed to contain random errors. Simulated responses of the aquifer to randomly specified contamination stresses as simulated by using a three-dimensional numerical simulation model are utilized for initial training of the surrogate models. The performance evaluation results obtained by using different surrogate models are also compared. The evaluation results demonstrate the different capabilities of the developed surrogate models. These capabilities lead to development of an efficient methodology for source characterization based on utilizing the trained and tested surrogate models in an inverse mode. The obtained results are satisfactory and show the potential applicability of the SOM and GPR-based surrogate models for unknown groundwater contaminant source characterization in an inverse mode. 展开更多
关键词 Surrogate Models UNKNOWN GROUNDWATER Contamination Sources Source characterIZATION EXPERIMENTAL site Contaminated Aquifers
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我国高放废物地质处置新突破
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作者 王驹 陈亮 +7 位作者 周志超 赵星光 田霄 季瑞利 马洪素 曹胜飞 凌辉 康明亮 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第S02期217-230,共14页
2019年5月6日,国家原子能机构批复了我国高放废物地质处置地下实验室建设工程立项建议书。2021年6月17日,地下实验室工程正式开工建设,标志着我国高放废物地质处置进入一个新的阶段——地下实验室阶段,实现了新的突破。本文介绍近五年(2... 2019年5月6日,国家原子能机构批复了我国高放废物地质处置地下实验室建设工程立项建议书。2021年6月17日,地下实验室工程正式开工建设,标志着我国高放废物地质处置进入一个新的阶段——地下实验室阶段,实现了新的突破。本文介绍近五年(2019-2024)来我国高放废物地质处置在法律法规、技术标准、场址评价、缓冲材料、工程技术、岩石力学、放射性核素迁移和安全评价等方面取得的新进展,重点介绍北山地下实验室工程建设及研究开发的新进展。 展开更多
关键词 中国 高放废物 地质处置 北山地下实验室 场址评价
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Ziegler-Natta催化剂活性中心的研究进展
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作者 唐剑 李秉毅 +1 位作者 崔楠楠 梁迎迎 《石油化工》 CAS CSCD 北大核心 2024年第7期1036-1043,共8页
Ziegler-Natta(Z-N)催化剂活性中心对催化剂和聚合物的性能具有重要影响,开展活性中心结构的研究将为催化剂结构和性能关系、催化机理等提供更深入的认识,是目前聚烯烃催化剂领域中的研究热点。介绍了不同谱学手段对活性中心的表征及对... Ziegler-Natta(Z-N)催化剂活性中心对催化剂和聚合物的性能具有重要影响,开展活性中心结构的研究将为催化剂结构和性能关系、催化机理等提供更深入的认识,是目前聚烯烃催化剂领域中的研究热点。介绍了不同谱学手段对活性中心的表征及对活性中心结构变化的原位监测,综述了通过构建模型催化剂并结合表面分析对活性中心结构进行模拟的研究,以及基于氯化镁晶体模型对活性中心结构的密度泛函理论计算研究,并对Z-N催化剂活性中心结构研究的发展方向进行了展望。 展开更多
关键词 ZIEGLER-NATTA催化剂 活性中心 结构表征 密度泛函理论计算
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Adaptive sampling strategy for characterizing spatial distribution of soil liquefaction potential using cone penetration test 被引量:1
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作者 Zheng Guan Yu Wang Tengyuan Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第4期1221-1231,共11页
Characterizing spatial distribution of soil liquefaction potential is critical for assessing liquefactionrelated hazards(e.g.building damages caused by liquefaction-induced differential settlement).However,in engineer... Characterizing spatial distribution of soil liquefaction potential is critical for assessing liquefactionrelated hazards(e.g.building damages caused by liquefaction-induced differential settlement).However,in engineering practice,soil liquefaction potential is usually measured at limited locations in a specific site using in situ tests,e.g.cone penetration tests(CPTs),due to the restrictions of time,cost and access to subsurface space.In these cases,liquefaction potential of soil at untested locations requires to be interpreted from limited measured data points using proper interpolation method,leading to remarkable statistical uncertainty in liquefaction assessment.This underlines an important question of how to optimize the locations of CPT soundings and determine the minimum number of CPTs for achieving a target reliability level of liquefaction assessment.To tackle this issue,this study proposes a smart sampling strategy for determining the minimum number of CPTs and their optimal locations in a selfadaptive and data-driven manner.The proposed sampling strategy leverages on information entropy and Bayesian compressive sampling(BCS).Both simulated and real CPT data are used to demonstrate the proposed method.Illustrative examples indicate that the proposed method can adaptively and sequentially select the required number and optimal locations of CPTs. 展开更多
关键词 Liquefaction potential Information entropy Cone penetration test(CPT) site characterization Compressive sampling
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麦芽糖酶-葡萄糖淀粉酶D246A异源表达及性质表征
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作者 高雨晴 董钢印 +3 位作者 张洪瑞 马占山 方丽 詹冬玲 《吉林大学学报(理学版)》 CAS 北大核心 2024年第3期742-749,共8页
以大型真菌灵芝中的麦芽糖酶-葡萄糖淀粉酶(MGAM)为研究对象,采用同源序列比对、同源模建、底物对接和定点突变等方法成功构建酶活力显著降低的突变体D246A.酶学性质表征结果表明:最适反应温度由野生型(wild type,WT)的65℃减少至60℃,... 以大型真菌灵芝中的麦芽糖酶-葡萄糖淀粉酶(MGAM)为研究对象,采用同源序列比对、同源模建、底物对接和定点突变等方法成功构建酶活力显著降低的突变体D246A.酶学性质表征结果表明:最适反应温度由野生型(wild type,WT)的65℃减少至60℃,突变体耐热能力下降;最适pH值由WT的6.0升高至7.0,有利于工程菌生长;半衰期由WT的2.0 h下降至1.5 h,酶稳定性降低.酶动力学结果表明:突变体D246A酶动力学曲线符合Michaelis方程,与WT相比,K_(m)值变大,表明酶与底物亲和力下降;V_(max)约降低至原来的1/4. 展开更多
关键词 定点突变 异源表达 性质表征 麦芽糖酶-葡萄糖淀粉酶
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Al_(2)O_(3)负载Pt基催化剂表面动态变化的谱学研究 被引量:1
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作者 何念秋 郑燕萍 陈明树 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第1期7-16,I0001,共11页
明确多相催化剂表面在反应过程的动态变化对催化剂的优化、设计有重要意义.我们通过控制Pt的不同负载量制备了一系列Al_(2)O_(3)负载的Pt/Al_(2)O_(3)催化剂,利用X-射线衍射、X-光电子能谱、球差扫描电镜、CO-探针的红外光谱、低能离子... 明确多相催化剂表面在反应过程的动态变化对催化剂的优化、设计有重要意义.我们通过控制Pt的不同负载量制备了一系列Al_(2)O_(3)负载的Pt/Al_(2)O_(3)催化剂,利用X-射线衍射、X-光电子能谱、球差扫描电镜、CO-探针的红外光谱、低能离子散射谱、程序升温氧化和拉曼光谱等研究Pt/Al_(2)O_(3)的表面结构和反应过程中的变化,以丙烷直接脱氢(PDH)反应为探针,考察反应过程存在“诱导”期的表面动态变化,特别是表面积碳、表面形貌、活性位点等的演化.进而与其催化反应性能关联,发现Pt纳米粒子(NP)和团簇上丙烷易深度脱氢或断裂C-C键生成CH_(4)的同时形成积碳、随后失去活性;而孤立的Pt单原子位点(SAC)上不易生成积碳、是丙烯生成的关键活性位. 展开更多
关键词 表面动态过程 原位表征 丙烷脱氢 Pt基催化剂 单原子催化剂
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湾位双键官能化苝酰亚胺的合成及其溶液自组装行为研究
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作者 赵浩儒 鄂曾泽 +6 位作者 顾丹丹 桑伟慧 韩天娇 廖作桂 陈珈 江晓泽 孙宾 《合成技术及应用》 CAS 2024年第2期33-40,共8页
通过对苝酰亚胺的改性,合成了湾位双键官能团化、侧链为燕尾链的苝酰亚胺衍生物1,7-vinyl-PDI-EH。通过控制变量、优化合成反应条件,以反应浓度3.5 mg/mL在色谱纯级别(HPLC)四氢呋喃中反应2 h时,目标产物产率最高。进一步采用紫外可见... 通过对苝酰亚胺的改性,合成了湾位双键官能团化、侧链为燕尾链的苝酰亚胺衍生物1,7-vinyl-PDI-EH。通过控制变量、优化合成反应条件,以反应浓度3.5 mg/mL在色谱纯级别(HPLC)四氢呋喃中反应2 h时,目标产物产率最高。进一步采用紫外可见分光光谱、荧光光谱以及浓度依赖光谱对其光物理性能和自组装行为进行表征,结果表明1,7-vinyl-PDI-EH在氯仿溶液中浓度达到1.1×10^(-4 )mol/L后随着浓度增大荧光淬灭,7.0×10^(-4) mol/L时分子产生明显自组装。通过氯仿和甲醇体系的双扩散晶体培养,得到1,7-vinyl-PDI-EH晶体,其在结晶状态下仍有一定荧光性能。 展开更多
关键词 苝酰亚胺 湾位取代 双键官能团化 合成 表征 溶液自组装
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核桃谷蛋白多肽及其肽锌螯合物的分离纯化、鉴定与结合位点分析
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作者 梅洁 李芳 +4 位作者 王晓雯 马慧 邱晓柔 刘思悦 孔令明 《食品科学》 EI CAS CSCD 北大核心 2024年第22期8-16,共9页
为提高核桃的附加值,以核桃粕为原料,将核桃谷蛋白多肽与锌进行螯合,利用扫描电子显微镜、傅里叶变换红外光谱、X射线衍射光谱等分析手段表征多肽与锌离子的螯合特征,并通过超滤、凝胶柱层析、液相色谱-串联质谱(liquid chromatography-... 为提高核桃的附加值,以核桃粕为原料,将核桃谷蛋白多肽与锌进行螯合,利用扫描电子显微镜、傅里叶变换红外光谱、X射线衍射光谱等分析手段表征多肽与锌离子的螯合特征,并通过超滤、凝胶柱层析、液相色谱-串联质谱(liquid chromatography-tandem mass spectrometry,LC-MS/MS)技术筛选出与锌结合能力较高的肽段,结合分子对接技术探究二者的具体结合位点和结合能力。结果表明,核桃谷蛋白多肽与锌离子发生了螯合反应,螯合前后多肽的表面微观结构和结晶程度均有显著差异;经超滤、凝胶柱层析分离后,F41组分螯合能力最强,为(117.43±1.99)mg/g;LC-MS/MS结合虚拟筛选得到5条无毒无潜在致敏性且具有潜在生物活性的肽段;利用分子对接技术模拟分析肽锌螯合物的结合过程,发现五肽Phe-Asp-Ala-Asp-Phe(FDADF)可与锌离子形成结构稳定的复合物,通过配位键、氢键和疏水相互作用结合,结合能最低,为-7.27 kcal/mol,结合位点主要为天冬氨酸侧链的羧基氧原子(Asp4:O-Zn)。本研究可为肽锌螯合物的开发应用提供理论依据。 展开更多
关键词 核桃谷蛋白多肽 肽锌螯合物 结构表征 分离纯化 结合位点
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镁离子型Birnessite的合成和表征 被引量:1
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作者 吴巧玲 孙尧俊 +2 位作者 黄月芳 费伦 龙英才 《分析测试学报》 CAS CSCD 1998年第2期20-23,共4页
采用MnO-4和Mn2+在强碱性条件下制得层状结构的Mg_Birnessite,用XRD(X射线多晶粉末衍射)、FT-IR(傅里叶红外光谱)、TG-DTG/DTA(热失重-微商热失重/热分析)等方法对它进行了表征。M... 采用MnO-4和Mn2+在强碱性条件下制得层状结构的Mg_Birnessite,用XRD(X射线多晶粉末衍射)、FT-IR(傅里叶红外光谱)、TG-DTG/DTA(热失重-微商热失重/热分析)等方法对它进行了表征。Mg_Birnesite在200~400℃时为无定形,在600℃生成结晶良好的Mn2O3相。CCl4、CH3OH、n_C6H14的吸附等温线类似于第三种类型的吸附等温线,在接近饱和的情况下都有凝聚现象产生。在600℃,比表面和吸附数据表明出现层状结构塌陷。吸附吡啶FT-IR谱表明在Mg_Birnesite中存在非质子酸(L酸)和质子酸(B酸)酸位。 展开更多
关键词 镁离子型 BIRNESsite 锰氧化物 Mg-Birnessite
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Identification and Characterization of Reverse Transcriptase Fragments of Long Interspersed Nuclear Elements (LINEs) in the <i>Morus notabilis</i>Genome 被引量:1
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作者 Bi Ma Youchao Xin +2 位作者 Lulu Kuang Fei Hou Ningjia He 《American Journal of Molecular Biology》 2017年第3期138-152,共15页
Reverse transcriptase (rt) fragments from LINE retrotransposons in the mulberry genome were analyzed in terms of heterogeneity, phylogeny, and chromosomal distribution. We amplified and characterized conserved domains... Reverse transcriptase (rt) fragments from LINE retrotransposons in the mulberry genome were analyzed in terms of heterogeneity, phylogeny, and chromosomal distribution. We amplified and characterized conserved domains of the rt using degenerate primer pairs. Sequence analyses indicated that the rt fragments were highly heterogeneous and rich in A/T bases. The sequence identity ranged from 31.8% to 99.4%. Based on sequence similarities, the rt fragments were categorized into eight groups. Furthermore, similar stop codon distribution patterns among a series of clones in the same group indicated that they underwent a similar evolutionary process. Interestingly, phylogenetic analyses of the rt fragments isolated from mulberry and 13 other plant species revealed that two distantly related taxa (mulberry and Paeonia suffruticosa) grouped together. It does not appear that this phenomenon resulted from horizontal transposable element transfer. Fluorescence in situ hybridization analysis revealed that most of the rt fragments were concentrated in the subtelomeric and pericentromeric regions of the mulberry chromosomes, but that these elements were not abundant in the mulberry genome. Future studies will focus on the potential roles of these elements in the subtelomeric and pericentromeric regions of the mulberry genome. 展开更多
关键词 iMorus notabilis LINE RETROTRANSPOSONS Reverse Transcriptase characterIZATION Fluorescence in site Hybridization
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Application of laser scanning for rock mass characterization and discrete fracture network generation in an underground limestone mine 被引量:4
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作者 Juan J.Monsalve Jon Baggett +1 位作者 Richard Bishop Nino Ripepi 《International Journal of Mining Science and Technology》 EI CSCD 2019年第1期131-137,共7页
Terrestrial laser scanning(TLS) is a useful technology for rock mass characterization. A laser scanner produces a massive point cloud of a scanned area, such as an exposed rock surface in an underground tunnel,with mi... Terrestrial laser scanning(TLS) is a useful technology for rock mass characterization. A laser scanner produces a massive point cloud of a scanned area, such as an exposed rock surface in an underground tunnel,with millimeter precision. The density of the point cloud depends on several parameters from both the TLS operational conditions and the specifications of the project, such as the resolution and the quality of the laser scan, the section of the tunnel, the distance between scanning stations, and the purpose of the scans. One purpose of the scan can be to characterize the rock mass and statistically analyze the discontinuities that compose it for further discontinuous modeling. In these instances, additional data processing and a detailed analysis should be performed on the point cloud to extract the parameters to define a discrete fracture network(DFN) for each discontinuity set. I-site studio is a point cloud processing software that allows users to edit and process laser scans. This software contains a set of geotechnical analysis tools that assist engineers during the structural mapping process, allowing for greater and more representative data regarding the structural information of the rock mass, which may be used for generating DFNs. This paper presents the procedures used during a laser scan for characterizing discontinuities in an underground limestone mine and the results of the scan as applied to the generation of DFNs for further discontinuous modeling. 展开更多
关键词 ROCK mass characterIZATION Laser SCANNING Discrete fracture network I-site STUDIO
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Methodology for Obtaining Optimal Sleeve Friction and Friction Ratio Estimates from CPT Data
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作者 Erick Baziw 《International Journal of Geosciences》 CAS 2023年第3期290-303,共14页
Cone penetration testing (CPT) is a cost effective and popular tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic penetrometer into penetrable soils and recording con... Cone penetration testing (CPT) is a cost effective and popular tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic penetrometer into penetrable soils and recording cone bearing (q<sub>c</sub>), sleeve friction (f<sub>c</sub>) and dynamic pore pressure (u) with depth. The measured q<sub>c</sub>, f<sub>s</sub> and u values are utilized to estimate soil type and associated soil properties. A popular method to estimate soil type from CPT measurements is the Soil Behavior Type (SBT) chart. The SBT plots cone resistance vs friction ratio, R<sub>f</sub> [where: R<sub>f</sub> = (f<sub>s</sub>/q<sub>c</sub>)100%]. There are distortions in the CPT measurements which can result in erroneous SBT plots. Cone bearing measurements at a specific depth are blurred or averaged due to q<sub>c</sub> values being strongly influenced by soils within 10 to 30 cone diameters from the cone tip. The q<sub>c</sub>HMM algorithm was developed to address the q<sub>c</sub> blurring/averaging limitation. This paper describes the distortions which occur when obtaining sleeve friction measurements which can in association with q<sub>c</sub> blurring result in significant errors in the calculated R<sub>f</sub> values. This paper outlines a novel and highly effective algorithm for obtaining accurate sleeve friction and friction ratio estimates. The f<sub>c</sub> optimal filter estimation technique is referred to as the OSFE-IFM algorithm. The mathematical details of the OSFE-IFM algorithm are outlined in this paper along with the results from a challenging test bed simulation. The test bed simulation demonstrates that the OSFE-IFM algorithm derives accurate estimates of sleeve friction from measured values. Optimal estimates of cone bearing and sleeve friction result in accurate R<sub>f</sub> values and subsequent accurate estimates of soil behavior type. 展开更多
关键词 Cone Penetration Testing (CPT) Optimal Estimation Geotechnical site characterization Sleeve Friction Cone Bearing Friction Ratio Iterative Forward Modelling (IFM) Soil Behavior Type (SBT)
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Technique for Estimating the Cone Bearing Smoothing Parameters
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作者 Erick Baziw 《International Journal of Geosciences》 2023年第7期603-618,共16页
Cone penetration testing (CPT) is an extensively utilized and cost effective tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic cone into penetrable soils and recordi... Cone penetration testing (CPT) is an extensively utilized and cost effective tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic cone into penetrable soils and recording the resistance to the cone tip (q<sub>c</sub> value). The measured q<sub>c</sub> values (after correction for the pore water pressure) are utilized to estimate soil type and associated soil properties based predominantly on empirical correlations. The most common cone tips have associated areas of 10 cm<sup>2</sup> and 15 cm<sup>2</sup>. Investigators also utilized significantly larger cone tips (33 cm<sup>2</sup> and 40 cm<sup>2</sup>) so that gravelly soils can be penetrated. Small cone tips (2 cm<sup>2</sup> and 5 cm<sup>2</sup>) are utilized for shallow soil investigations. The cone tip resistance measured at a particular depth is affected by the values above and below the depth of interest which results in a smoothing or blurring of the true bearing values. Extensive work has been carried out in mathematically modelling the smoothing function which results in the blurred cone bearing measurements. This paper outlines a technique which facilitates estimating the dominant parameters of the cone smoothing function from processing real cone bearing data sets. This cone calibration technique is referred to as the so-called CPSPE algorithm. The mathematical details of the CPSPE algorithm are outlined in this paper along with the results from a challenging test bed simulation. 展开更多
关键词 Cone Penetration Testing (CPT) Geotechnical site characterization Optimal Estimation Iterative Forward Modelling (IFM) Monte Carlo Techniques Calibration
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转基因抗草甘膦棉花R1-3株系的分子特征鉴定 被引量:1
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作者 马燕斌 李换丽 +5 位作者 文晋 周仙婷 秦欣 王霞 王新胜 李燕娥 《中国农业科学》 CAS CSCD 北大核心 2023年第17期3277-3284,共8页
【目的】通过转化抗草甘膦除草剂基因G10aroA获得抗草甘膦除草剂的棉花转基因株系,对其进行分子特征鉴定分析,为今后棉花育种利用该株系提供必要的分子依据。【方法】利用农杆菌介导法,在草甘膦筛选条件下,通过组织培养获得棉花再生株系... 【目的】通过转化抗草甘膦除草剂基因G10aroA获得抗草甘膦除草剂的棉花转基因株系,对其进行分子特征鉴定分析,为今后棉花育种利用该株系提供必要的分子依据。【方法】利用农杆菌介导法,在草甘膦筛选条件下,通过组织培养获得棉花再生株系,利用Western blot对转基因棉花株系不同组织的外源蛋白表达进行检测;通过Southern blot确定株系中外源G10aroA整合位点的拷贝数;利用TAIL-PCR扩增外源基因整合位点侧翼序列,并通过NCBI BLAST工具比较分析其定位的染色体位置。【结果】通过草甘膦筛选,利用组织培养获得R1-3棉花再生株系;Western blot结果表明,外源基因在叶、苞叶、花、茎中均可正常表达,其蛋白大小约为46 kDa,与预期目标条带一致;基因组DNA酶切后杂交结果显示,R1-3株系外源序列的整合位点为单拷贝插入,其中,KpnⅠ酶切的杂交条带位于约6557 bp处,EcoRⅠ酶切的2条杂交带位于略大于4316 bp处;侧翼序列比对结果显示,外源序列融合到陆地棉A或D基因组的第11号染色体上,且在交换插入的过程中,左右边界的融合位点分别位于该染色体47525303和47525449处。另外,利用特异引物进行PCR鉴定,可知左侧融合位点可扩增出约300 bp的预期特定目标条带,右侧融合位点可扩增出约600 bp的预期特定目标条带。【结论】获得具有稳定遗传特征的R1-3转基因棉花株系,不同组织中外源基因编码的蛋白均有表达,提高了该株系对草甘膦的高抗性。含有G10aroA的外源序列为单个位点插入,融合位点位于陆地棉A或D基因组第11号染色体上,该融合位点处缺失约146 bp的核苷酸序列。 展开更多
关键词 陆地棉 抗草甘膦棉花 拷贝数 融合位点 分子特征
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有色冶炼场地重金属污染特征与修复研究进展 被引量:2
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作者 曾嘉庆 高文艳 +5 位作者 李雪 李楚璇 唐璐 可文舜 罗兴华 薛生国 《中国有色金属学报》 EI CAS CSCD 北大核心 2023年第10期3440-3461,共22页
重金属污染是世界各国面临的重大环境问题。随着有色金属产业升级,资源型城市及周边地区出现大面积的工业遗弃场地,存在极大的环境风险。针对我国有色冶炼工艺多样、地质条件复杂、污染溯源难等问题,对2002~2022年间发表的冶炼场地污染... 重金属污染是世界各国面临的重大环境问题。随着有色金属产业升级,资源型城市及周边地区出现大面积的工业遗弃场地,存在极大的环境风险。针对我国有色冶炼工艺多样、地质条件复杂、污染溯源难等问题,对2002~2022年间发表的冶炼场地污染特征研究和工程修复案例进行系统分析。综述了有色金属冶炼场地的精细刻画、污染形成、污染传输、污染阻控等方面的研究进展;明晰土壤-地下水系统重金属的生物地球化学过程,厘清污染物在复杂水文地质条件下的迁移转化规律,探讨污染场地土壤-地下水协同修复技术耦合与策略制定;分析了重金属污染场地修复技术的优缺点,提出了有色冶炼场地土壤-地下水协同修复的主要研究方向,为工业遗弃场地的环境风险管控与重金属污染防治提供科学参考。 展开更多
关键词 有色冶炼场地 重金属污染 精细刻画 土壤-地下水协同修复 修复策略
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二氧化碳加氢制甲醇过程中铜基催化剂活性位点研究进展
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作者 时永兴 林刚 +3 位作者 孙晓航 蒋韦庚 乔大伟 颜彬航 《化工进展》 EI CAS CSCD 北大核心 2023年第S01期287-298,共12页
二氧化碳加氢制甲醇反应研究对解决能源紧缺和环境问题具有重要意义。以Cu/ZnO/Al_(2)O_(3)为代表的铜基催化剂因其反应活性高、成本低廉而备受关注,受限于催化剂中Cu物种的电子结构多样性与表征技术的发展水平,铜基催化剂的真实活性位... 二氧化碳加氢制甲醇反应研究对解决能源紧缺和环境问题具有重要意义。以Cu/ZnO/Al_(2)O_(3)为代表的铜基催化剂因其反应活性高、成本低廉而备受关注,受限于催化剂中Cu物种的电子结构多样性与表征技术的发展水平,铜基催化剂的真实活性位点、反应机理尚不清楚。本文综述了二氧化碳加氢制甲醇过程中铜基催化剂活性位点的研究进展,并结合原位表征技术的研究进展对其反应机理进行综述。研究人员结合多种先进表征手段确定了活性位点的结构和组成,同时揭示了不同催化剂结构对反应性能的影响。通过原位表征技术的应用,可以实时观察反应过程中催化剂的结构变化,揭示了反应关键步骤和催化剂的作用方式。未来可以结合更多原位表征技术和计算模拟方法,探索催化剂微观结构和反应机理,以更高的反应性能制备绿色甲醇。 展开更多
关键词 二氧化碳加氢 甲醇合成 铜基催化剂 活性位点 原位表征技术
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