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Transparent characterization and quantitative analysis of broken gangue's 3D fabric under the bearing compression 被引量:1
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作者 Junmeng Li Yanli Huang +5 位作者 Shenyang Ouyang Yachao Guo Huadong Gao Laiwei Wu Yibing Shi Lei Zhu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第2期335-345,共11页
Broken gangue has been extensively used in rockfill dams,subgrade,embankment,foundation cushion and other engineering construction.The deformation characteristics of broken gangue under the bearing compression play a ... Broken gangue has been extensively used in rockfill dams,subgrade,embankment,foundation cushion and other engineering construction.The deformation characteristics of broken gangue under the bearing compression play a decisive role in the firmness,stability and safety of these structures(buildings),and the meso-fabric change of broken gangue under the bearing compression significantly affects its macro deformation.In this study,the transparent characterization and quantitative analysis of 3D fabric of broken gangue under the bearing compression were performed through CT scanning test,image processing and 3D reconstruction technology,and the influence mechanism of internal fabric of broken gangue on its macro deformation was revealed.The results show that:In the loading stage of 0–2 MPa,the sharp corners,thin edges on the blocks and the bar-shaped and blade-shaped blocks with poor regularity are broken first under the bearing compression;in the loading stage of 2–8 MPa,a large number of larger particles in the sample are crushed in the mode of fragmentation;in the loading stage of 8–10 MPa,the breakage degree of samples is relieved.The axial displacement of the block inside the sample occurs,as well as the lateral displacement of the block converging to the central axis of the sample.In the rapid deformation stage,the macro deformation of the broken gangue is mainly caused by the rearrangement and adjustment of the block structure and the breakage of the block;in the slow deformation stage,it is mainly caused by the breakage of the block;in the stable deformation stage,it is mainly caused by the optimization and adjustment of the bearing skeleton in the sample. 展开更多
关键词 Bearing compression Broken gangue 3D fabric Transparent characterization quantitative analysis
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Theoretical Study on Quantitative Characterization of Interlayer Interference in Multi-Layer Commingled Production 被引量:1
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作者 Pengfei Mu Shaopeng Wang +2 位作者 Jie Tan Hanqing Zhao Li’an Zhang 《Journal of Power and Energy Engineering》 2021年第4期21-29,共9页
X oilfield is a typical layered reservoir with a large vertical span and many oil-bearing formations. There are significant differences in reservoir types and fluid properties among various formations. The interlayer ... X oilfield is a typical layered reservoir with a large vertical span and many oil-bearing formations. There are significant differences in reservoir types and fluid properties among various formations. The interlayer interference is severe in the development process. At present, the interlayer interference research based on dynamic monitoring data cannot meet development adjustment needs. Combined with the field test results, through the indoor physical simulation experiment method, dynamic inversion method, and reservoir engineering method, this paper analyzes the main control factors and interference mechanism of interlayer interference, studies the variation law of interference coefficient, improves and forms the quantitative characteristic Theory of interlayer interference in multi-layer commingled production, and provides theoretical guidance for the total adjustment of the middle strata division in the oilfield. 展开更多
关键词 Thin Interbedded Reservoir Multi-Layer Production Interbedded Interference quantitative characterization Theoretical Research
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STUDY ON THE SEQUENCE STRUCTURE OF BUTADIENE-STYRENE RUBBER BY ^(13)C-NMR METHOD Ⅲ. QUANTITATIVE CHARACTERIZATION OF SEQUENCE STRUCTURE
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作者 陈晓农 胡力平 +1 位作者 严宝珍 焦书科 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1990年第3期269-278,共10页
The quantitative description of the sequence structure of emulsion-processed SBR and solution-processed SBR (by lithium catalyst)was carried out based on their spectral data Of ^(13)C-NMR.The calculating formulae whic... The quantitative description of the sequence structure of emulsion-processed SBR and solution-processed SBR (by lithium catalyst)was carried out based on their spectral data Of ^(13)C-NMR.The calculating formulae which could be used to obtain diad concentration from the peak intensifies of carbon spectra, average block length, average number of block, and the microstructure composition of the molecular chain were derived. The quantitative result showed that on the molecular chain styrene unit had the tendency to attach to trans-1,4 butadiene unit. The calculated result of the microstructure was in good agreement with that obtained through IR measurement. 展开更多
关键词 Sequence structure quantitative characterization SBR diad concentration average block length average number of block.
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Research on Bribery Characterization of Property Developers in Land Market: Based on Quantitative Analysis
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作者 Hongxia ZHANG Shukui TAN +1 位作者 Li XIA Chunhong JIANG 《Asian Agricultural Research》 2015年第12期52-58,共7页
Taking Wuhan,Nanjing and Guangzhou as examples and using Logistic model and Moran index,this paper made a quantitative analysis on bribery characterization of developers in land market. It found that( i) bribery behav... Taking Wuhan,Nanjing and Guangzhou as examples and using Logistic model and Moran index,this paper made a quantitative analysis on bribery characterization of developers in land market. It found that( i) bribery behavior of developers is promoted by supply and demands;( ii) bribery behavior of developers takes on regional agglomeration and difference. It reached following conclusions:( i) under the influence of macro factors and micro factors,bribery behavior of developers is rational selection after full consideration of institutional environment and corporate strength,and is passive to a certain extent;( ii) bribery behavior of developers has certain spatial correlation,and the high-high correlation characteristic is most significant. 展开更多
关键词 LAND MARKET Property DEVELOPERS BRIBERY characterization quantitative analysis
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“Second quantitative characterization”and its application in fractured-vuggy carbonate reservoirs
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作者 LI Yong DENG Xiaojuan +4 位作者 NING Chaozhong WANG Qi CUI Shiti ZHANG Qi WAN Xiaoguo 《Petroleum Exploration and Development》 CSCD 2022年第4期797-809,共13页
The Ordovician fracture-vug carbonate reservoirs of Tarim Basin,are featured by developed vugs,caves and fractures.The strong heterogeneity results in huge uncertainty when these reservoirs are quantitatively characte... The Ordovician fracture-vug carbonate reservoirs of Tarim Basin,are featured by developed vugs,caves and fractures.The strong heterogeneity results in huge uncertainty when these reservoirs are quantitatively characterized using merely static seismic data.The effective quantitative characterization of the reservoirs has been an urgent problem to be solved.This study creatively proposes the"second quantitative characterization"technique with the combination of dynamic and static data based on the primary static quantitative characterization and fully considering lots of key influence factors when conducting characterization.In this technique,dynamic analysis methods such as well testing,production rate transient analysis,dynamic reserve evaluation and dynamic connectivity evaluation are used to get understandings on this kind of reservoir.These understandings are used as statistical parameters to constrain the inversion of seismic wave impedance to improve the relationship between wave impedance and porosity and determine the fracture-vug morphology,calculate dynamic reserves,and then a more accurate fracture-vugmodel can be selected and used to calculate the oil-water contact inversely based on the results of"second quantitative characterization".This method can lower the uncertainties in the primary quantitative characterization of fracture-vug reservoirs,enhance the accuracy of characterization results significantly,and has achieved good application results in the fracture-vug carbonate reservoirs of Tarim Basin. 展开更多
关键词 Tarim Basin ORDOVICIAN CARBONATE fracture-vug reservoir uncertainty static quantitative characterization dynamic analysis combination of dynamic and static data second quantitative characterization
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Quantitative characterization of vertical zonation of Mesozoic granite weathering reservoirs in the coastal area of eastern Fujian Province,China
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作者 Jing-Song Hu Yi-Ming Jiang +3 位作者 Hua-Feng Tang Wen-Rui Ma Peng Tao Ning-Yuan Sun 《Petroleum Science》 SCIE EI CSCD 2023年第5期2664-2682,共19页
Weathering crust reservoirs have obvious vertical zonation,which is the focus of weathering crust reservoir research,but there is a lack of quantitative characterization indexes.To achieve the quantitative characteriz... Weathering crust reservoirs have obvious vertical zonation,which is the focus of weathering crust reservoir research,but there is a lack of quantitative characterization indexes.To achieve the quantitative characterization of granite weathering crust reservoir and provide the basis for oil exploration of granite weathering crust buried hill reservoir,in this paper,the vertical zonation of granite weathering crust reservoir is quantitatively divided by testing and analyzing the uniaxial compressive strength(UCS),magnetic susceptibility(MS),permeability,and chemical index of alteration(CIA)of the Mesozoic granite weathering crust in the coastal area of eastern Fujian.The results show that the granite weathering crust reservoir can be divided into four zones vertically:a soil zone(SZ),weathered and dissolved zone(WDZ),fracture zone(FZ),and bedrock zone(BZ).A cataclastic area is developed in the FZ and BZ,in which structural fractures are well-developed,the fracture surface density is usually greater than 200 m/m^(2),and the contribution to the fractures in the rock mass is up to about 50%,making this the sweet spot of the reservoir.In the SZ,the rocks are loose,and the pores are well-developed.The UCS is less than 10 MPa,and the average rate of change of the UCS(Δ_(σ))is 0.90.The average permeability is 2823.00 mD,and the average rate of change of the permeability(Δ_(κ))is 5.13.The average CIA is 74.9%.The average clay mineral content is 7%.The rocks in the WDZ have been significantly weathered by physical and chemical processes,and the weathering fractures and dissolution pores are well-developed.The average UCS is 18.2 MPa,and the averageΔ_(σ)is 0.70.The average permeability is 143.80 mD,and averageΔ_(κ)is 4.17.The average CIA is 65.3%.The average clay mineral content is 4%.Under the influence of tectonic movement and physical weathering,the rocks in the FZ have developed structural fractures and a few weathered fractures.The average UCS is 57.9 MPa,and the averageΔ_(σ)is 0.18.The average permeability is 5.50 mD,and the averageΔ_(κ)is 2.55.The average CIA is 61.6%.The average clay mineral content is 2%.In the BZ,the rocks are intact and hard.The average UCS is 69.9 MPa,and the average Ds is 0.13.The average permeability is 1.46 mD,and the averageΔ_(κ)is 1.43.The average CIA is 57.8%.The average clay mineral content is less than 1%.The multi-parameter combination of the UCS,Δ_(σ),permeability,Δ_(κ),CIA,and clay mineral content achieved good results in the division of the zones of the weathering crust.The UCS increases gradually from top to bottom,while Ds,permeability,Δ_(κ),CIA,and clay mineral content all decrease gradually.In addition,based on the petrophysical parameters of the rocks,including the density,resistivity,and acoustic velocity,a good division effect was also achieved,which can provide a basis for the vertical zonation of the granite buried-hill weathering crust reservoir. 展开更多
关键词 Granite weathering crust Vertical zonation of reservoir quantitative characterization Eastern Fujian Mesozoic granite
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Quantitative characterization of tight gas sandstone reservoirs using seismic data via an integrated rock-physics-based framework
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作者 Zhi-Qi Guo Xiao-Ying Qin Cai Liu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3428-3440,共13页
Seismic characterizing of tight gas sandstone (TGS) reservoirs is essential for identifying promising gas-bearing regions. However, exploring the petrophysical significance of seismic-inverted elastic properties is ch... Seismic characterizing of tight gas sandstone (TGS) reservoirs is essential for identifying promising gas-bearing regions. However, exploring the petrophysical significance of seismic-inverted elastic properties is challenging due to the complex microstructures in TGSs. Meanwhile, interbedded structures of sandstone and mudstone intensify the difficulty in accurately extracting the crucial tight sandstone properties. An integrated rock-physics-based framework is proposed to estimate the reservoir quality of TGSs from seismic data. TGSs with complex pore structures are modeled using the double-porosity model, providing a practical tool to compute rock physics templates for reservoir parameter estimation. The VP/VS ratio is utilized to predict the cumulative thickness of the TGS reservoirs within the target range via the threshold value evaluated from wireline logs for lithology discrimination. This approach also facilitates better capturing the elastic properties of the TGSs for quantitative seismic interpretation. Total porosity is estimated from P-wave impedance using the correlation obtained based on wireline log analysis. After that, the three-dimensional rock-physics templates integrated with the estimated total porosity are constructed to interpret microfracture porosity and gas saturation from velocity ratio and bulk modulus. The integrated framework can optimally estimate the parameters dominating the reservoir quality. The results of the indicator proposed based on the obtained parameters are in good agreement with the gas productions and can be utilized to predict promising TGS reservoirs. Moreover, the results suggest that considering microfracture porosity allows a more accurate prediction of high-quality reservoirs, further validating the applicability of the proposed method in the studied region. 展开更多
关键词 Tight gas sandstone reservoirs quantitative reservoir characterization Rock-physics-based framework Microfracture porosity Rock physics template
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Quantitative Characterization and Genesis Analysis of Complex Modals of Pore Structure in Alluvial-Fan Sandy Conglomerate Reservoirs
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作者 Senlin Yin Juan Chen +2 位作者 Yukun Chen Xiaoguang Wang Xuzhuang Zhu 《石油天然气学报》 CAS 2017年第3期1-12,共12页
新疆油田冲积扇砂砾岩储层岩石类型多样,颗粒大小混杂,分选极差,储层孔隙结构具有典型的多种模态特征,即单模态、双模态与复模态等。利用铸体薄片、压汞、恒速压汞资料定量表征了七东1区砂砾岩储层复杂模态孔隙特征以及连通特征,利用多... 新疆油田冲积扇砂砾岩储层岩石类型多样,颗粒大小混杂,分选极差,储层孔隙结构具有典型的多种模态特征,即单模态、双模态与复模态等。利用铸体薄片、压汞、恒速压汞资料定量表征了七东1区砂砾岩储层复杂模态孔隙特征以及连通特征,利用多元回归分析法建立复杂模态孔隙结构储层的识别模型。以此为基础,分析了冲积扇砂砾岩储层孔隙结构复杂模态成因机制。研究表明:单模态储层主要以Ⅰ类储层为主,双模态储层以Ⅱ、Ⅲ类储层为主,复模态储层以Ⅲ类储层为主。从单模态类型到复模态孔喉组合类型,孔隙发育由好变差,由连通较好的网状到连通较差的星点状,面孔率降低,平均孔径减小,孔喉配位数减小。利用已有147块样品统计发现,七东1区下克拉玛依组储层中单模态储层占19%、双模态储层占48%、复模态储层占33%。由此提出不同模态判断标准,建立了储层孔隙结构预测模型,揭示了储层构型、成岩后作用及注水(聚)开发中后期的系列变化等多因素是导致形成复杂模态的原因。 展开更多
关键词 学术期刊 石油天然气 中国 期刊评价 学报 研制工作 项目组
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Structural Characterization of Lignins Isolated from Caragana sinica Using FT-IR and NMR Spectroscopy 被引量:3
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作者 XIAO Ling-ping SHI Zheng-jun +2 位作者 XU Feng SUN Run-cang Amar K Mohanty 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2011年第9期2369-2376,共8页
In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were c... In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were characterized by Fourier transform infrared spectroscopy(FT-IR) and 1D and 2D Nuclear Magnetic Resonance(NMR).FT-IR spectra revealed that the "core" of the lignin structure did not significantly change during the treatment under the conditions given.The results of 1H and 13C NMR demonstrated that the lignin fraction L2,isolated with 70% ethanol containing 1% NaOH,was mainly composed of β-O-4 ether bonds together with G and S units and trace p-hydroxyphenyl unit.Based on the 2D HSQC NMR spectrum,the ethanol organosolv lignin fraction L1,extracted with 70% ethanol,presents a predominance of β-O-4′ aryl ether linkages(61% of total side chains),and a low abundance of condensed carbon-carbon linked structures(such as ββ′,β-1′,and β-5′) and a lower S/G ratio.Furthermore,a small percentage(ca.9%) of the linkage side chain was found to be acylated at the γ-carbon. 展开更多
关键词 Caragana sinica LIGNIN Structural characterization ft-ir NMR
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Studies on a Novel Characteristic Atom-pair Holographic Code Applied to Quantitative Structure-chromatographic Retention Relationship of Organic Compounds 被引量:1
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作者 ZHOU Peng TIAN Fei-Fei +1 位作者 WANG Jiao-Na LI Zhi-Liang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第11期1337-1342,共6页
6 Atomic fragment types of organic compound have been defined, and the multilevel atom-pair frequency matrix has been constructed according to the occurrence number in pairs of atomic fragments with different bond len... 6 Atomic fragment types of organic compound have been defined, and the multilevel atom-pair frequency matrix has been constructed according to the occurrence number in pairs of atomic fragments with different bond lengths in the molecule. On the basis of them, a novel molecular coding technique: characteristic atom-pair holographic code (CAHC), is obtained. To some extent, this method exhibits a large number of benefits at the same time. For example, it can calculate 2D molecular topological descriptor easily, operate without difficulty and possess definite physicochemical meaning of 3D molecular structural characterization methods, and may fetch the complicated information of molecule, etc. Therefore, it is appropriate for the study on quantitative structure-property/activity relationship (QSPR/QSAR) of medicines and biological molecules. We attempt in this paper to utilize the method of CAHC to the quantitative prediction of reversed-phase liquid chromatogram (RPLC) retention data of 33 purine derivatives and 24 steroids. The fitting multiple correlation coefficient R2, cross-validated multiple correlation coefficient Q2 and predicted ability Q^2 pred over test set's samples of obtained partial least-square (PLS) regression model are respectively 0.990, 0.893 and 0.977, 0.897, 0.941. 展开更多
关键词 characteristic atom-pair holographic code quantitative structure-chromatographic retention relationship characterization of molecular structure partial least-square regression
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Study on Quantitative Character for Anatomy in Tomato Seedling Stem
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作者 LI Fuheng WEI Liyan YU Longfeng QI Donglai ZHANG Da 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第1期14-18,共5页
The results of quantitative characters for anatomy in stems of three varieties tomatoes seedlings showed that the cell population between vascular bundle and epidermis, the cellular layers among vascular bundles and t... The results of quantitative characters for anatomy in stems of three varieties tomatoes seedlings showed that the cell population between vascular bundle and epidermis, the cellular layers among vascular bundles and the cell population in an unit area (mm^2) of no vascular bundle areas were similar and there had small difference among three varieties. On the foundation of these studies, the developmental mechanism of tomato seedling stem was discussed. 展开更多
关键词 Lycopersicun esculentum STEM anatomic structure quantitative character DEVELOPMENT
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Ecological Coupling Analysis and Genetic Effect Evaluation of Quantitative Characters in Lonicera edulis
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作者 Shibo LAN 《Agricultural Biotechnology》 CAS 2015年第1期6-8,15,共4页
Lonicera edulis is a perennial berry shrub that prefers the cold and wet climate, with high nutritional and medicinal value. In this study, ecological cou- pling capability of L. edulis with light, heat, water and soi... Lonicera edulis is a perennial berry shrub that prefers the cold and wet climate, with high nutritional and medicinal value. In this study, ecological cou- pling capability of L. edulis with light, heat, water and soil resources in cold regions was investigated to analyze comprehensively ecological effects of quantitative characters and genetic effects of parents, aiming at providing a theoretical basis for the breeding, introduction and domestication of fine varieties of L. edulis in cold regions of China. The results showed that fruit characters in L. edulis exhibited certain variations among different habitat types. To be specific, fruit vertical diame- ter varied slightly, fruit horizontal diameter varied greatly and seed number varied maximally, with the average variance coefficients of 9.38%, 11.92% and 20. 64%, respectively; in addition, fruit characters in L. edtdis exhibited moderate herilability, moderate genetic gain and low level of genetic differentiation; the heritability of fruit vertical diameter, fruit horizontal diameter and seed number was 0.825, 0. 559 and 0. 627, respectively; the genetic gain of these three fruit characters was 7.53%, 5.72% and 11. 94%, respectively, resulting in significant economical benefits. 展开更多
关键词 Lonicera edulis Ecological coupling quantitative character Genetic effects Genetic gain HERITABILITY
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Qualitative and quantitative ATR-FTIR analysis and its application to coal char of different ranks 被引量:19
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作者 Andrew O.Odeh 《燃料化学学报》 EI CAS CSCD 北大核心 2015年第2期129-137,共9页
This paper analyzes the coal to char stages of char formation of six coals of different ranks by using Fourier transform infrared coupled w ith attenuated total reflectance(ATR-FTIR).The chars w ere obtained by coal p... This paper analyzes the coal to char stages of char formation of six coals of different ranks by using Fourier transform infrared coupled w ith attenuated total reflectance(ATR-FTIR).The chars w ere obtained by coal pyrolysis carried out at temperature range of 450~700℃.The data obtained show s the pragmatic disappearance of the aliphatic hydrogen content w ith increasing char formation temperature.Numerical evaluation of the spectra enabled the determination of aromaticity,fa.The aromaticity w as found to be betw een 0.66~0.79 for lignite,0.75~0.90 for sub-bituminous,0.84~1.00 for low volatile bituminous,0.83~1.00 for high volatile bituminous,0.94~1.00 for semi-anthracite,and 0.97~1.00 for anthracite respectively.With increasing rank of coal samples,spectra exhibit rising aromaticity and enhanced condensation of aromatic rings,w hereas the aliphatic chain lengths decrease. 展开更多
关键词 qualitative quantitative ft-ir coal char
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Revisiting support optimization at the Driskos tunnel usinga quantitative risk approach 被引量:5
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作者 J.Connor Langford N.Vlachopoulos M.S.Diederichs 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第2期147-163,共17页
With the scale and cost of geotechnical engineering projects increasing rapidly over the past few decades,there is a clear need for the careful consideration of calculated risks in design.While risk is typically dealt... With the scale and cost of geotechnical engineering projects increasing rapidly over the past few decades,there is a clear need for the careful consideration of calculated risks in design.While risk is typically dealt with subjectively through the use of conservative design parameters,with the advent of reliability-based methods,this no longer needs to be the case.Instead,a quantitative risk approach can be considered that incorporates uncertainty in ground conditions directly into the design process to determine the variable ground response and support loads.This allows for the optimization of support on the basis of both worker safety and economic risk.This paper presents the application of such an approach to review the design of the initial lining system along a section of the Driskos twin tunnels as part of the Egnatia Odos highway in northern Greece.Along this section of tunnel,weak rock masses were encountered as well as high in situ stress conditions,which led to excessive deformations and failure of the as built temporary support.Monitoring data were used to validate the rock mass parameters selected in this area and a risk approach was used to determine,in hindsight,the most appropriate support category with respect to the cost of installation and expected cost of failure.Different construction sequences were also considered in the context of both convenience and risk cost. 展开更多
关键词 Driskos tunnel quantitative risk analysis Rock mass characterization Underground suppor Reliability-based design FLYSCH
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Study on the Quantitative Structure-toxicity Relationships for the Selected Esters by Using Molecular Electronegativity Interaction Vector (MEIV) 被引量:4
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作者 李建凤 廖立敏 王碧 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第9期1225-1232,共8页
The molecular electronegativity interaction vector (MEIV) was used to describe the molecular structure of 30 selected esters. Two excellent QSTR models were built up by using multiple linear regression (MLR) and p... The molecular electronegativity interaction vector (MEIV) was used to describe the molecular structure of 30 selected esters. Two excellent QSTR models were built up by using multiple linear regression (MLR) and partial least-squares regression (PLS). The correlation coefficients (R) of the two models were 0.945 and 0.941, respectively. The models were evaluated by performing the cross validation with the leave-one-out (LOO) procedure. The cross-verification correlation coefficients (RCV) of the two models were 0.921 and 0.919, respectively. The results showed that the models constructed in this work could provide estimation stability and favorable predictive ability. 展开更多
关键词 ESTERS tetrahymena pyriformis half-inhibitory growth concentration (IGC50) structural characterization quantitative structure toxicity relationship (QSTR)
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Research on Characters of Leaf Epidermal Cells' Quantities of Solanaceous Vegetable Crops
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作者 YU Longfeng AN Fuquan +1 位作者 GAO Jinhe LI Fuheng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第3期1-5,共5页
Tomatoes, peppers and eggplants' seedings were used as experiment materials to study the leaf development mechanism of solanaceous vegetable crops by using blot observation method. Results showed that an increasing t... Tomatoes, peppers and eggplants' seedings were used as experiment materials to study the leaf development mechanism of solanaceous vegetable crops by using blot observation method. Results showed that an increasing trend was presented at the density of cells and stomata in upper and lower epidermis, but a declined trend was presented at the cells' diameters and the size of stomata with the joint position rising. At the same joint position, no matter in adaxial side or abaxial side, there were some differences among cells diameters, size of stomata, density of cells and stomata. 展开更多
关键词 solanaceous vegetable crop LEAF quantitative character
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Extraction of Dyes from Sunflower Petal and Their Fourier Transform Infrared Characterization
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作者 Gboyega Oluwaseun Oyeleke Ibraheem Abimbade Abdulazeez +2 位作者 Ajisola Agnes Adebisi Kehinde Nasiru Oyekanmi Segun Olaitan Akinbode 《Organic Polymer Material Research》 2021年第2期1-6,共6页
Three solvents of different polarities(water,methanol and 1%NaOH solution)were used to extract dyes that produced different shades from dried sunflower(Helianthus annuus)petal.The extraction procedures using different... Three solvents of different polarities(water,methanol and 1%NaOH solution)were used to extract dyes that produced different shades from dried sunflower(Helianthus annuus)petal.The extraction procedures using different solvent types were carried out separately.The dye extracts were thereafter subjected to Fourier Transform Infrared Spectrometry(FT-IR)analysis for characterization in terms of functional groups.The intensities of the extracted dyes on the shade of colours obtained on pieces of cotton material varied from yellow in methanolic extract to light yellow in aqueous and black in 1%NaOH solution extracts.The results obtained from the FT-IR analysis revealed the presence of several useful functional groups such as N-H,C=H,O-H and C=O in the extracts. 展开更多
关键词 SUNFLOWER PETAL Solvents Dye extract ft-ir Functional group characterization
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Quantitative characterization of granular size segregation:A critical review
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作者 Cong Leng Chengfeng Sun +1 位作者 Zhehan Liao Jian Xu 《Particuology》 SCIE EI CAS CSCD 2024年第12期166-177,共12页
Granular size segregation is an inevitable phenomenon in both natural and industrial processes.To understand the underlying mechanisms and develop effective optimization strategies,it is essential to employ robust met... Granular size segregation is an inevitable phenomenon in both natural and industrial processes.To understand the underlying mechanisms and develop effective optimization strategies,it is essential to employ robust methodologies that can quantitatively characterize and evaluate size segregation behaviors in granular systems.This review critically examines a wide variety of state-of-the-art methodologies from recent studies to quantify granular size segregation.The features of these methodologies are extracted and organized into a comprehensive framework.Four key questions are thoroughly discussed:evaluation criteria for identical segregation states,sensitivity to sample size,the influence of sampling division pattern,and the capability of handling multiple-component system.Finally,we provide an outlook on the future development of advanced and effective methodologies for granular size segregation characterization. 展开更多
关键词 Granular system Size segregation quantitative characterization Multi-scale framework
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Triple three-dimensional MS/MS spectrum facilitates quantitative ginsenosides-targeted sub-metabolome characterization in notoginseng
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作者 Ke Zhang Jinru Jia +5 位作者 Ting Li Wenjing Liu Pengfei Tu Jian-Bo Wan Jun Li Yuelin Song 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2024年第9期4045-4058,共14页
Although serving as the workhorse,MS/MS cannot fully satisfy the analytical requirements of quantitative sub-metabolome characterization.Because more information intrinsically correlates to more structural and concent... Although serving as the workhorse,MS/MS cannot fully satisfy the analytical requirements of quantitative sub-metabolome characterization.Because more information intrinsically correlates to more structural and concentration clues,here,efforts were devoted to comprehensively tracing and deciphering MS/MS behaviors through constructing triple three-dimensional(3×3D)-MS/MS spectrum.Ginsenosides-targeted metabolomics of notoginseng,one of the most famous edible medicinal plants,was employed as a proof-of-concept.Serial authentic ginsenosides were deployed to build the correlations between 3×3D-MS/MS spectra and structure/concentration features.Through assaying ginsenosides with progressive concentrations using QTOF-MS to configure 1st 3D spectrum,the generations of MS1 spectral signals,particularly multi-charged multimer anions,e.g.,[2Me2H]^(2-) and[2M+2HCOO]^(2-) ions,relied on both concentration and the amount of sugar chains.By programming progressive collision energies to the front collision cell of Qtrap-MS device to gain 2^(nd) 3D spectrum,optimal collision energy(OCE)corresponding to the glycosidic bond fission was primarily correlated with the masses of precursor and fragment ions and partially governed by the glycosidation site.The quantitative relationships between OCEs and masses of precursor and fragment ions were utilized to build large-scale quantitative program for ginsenosides.After applying progressive exciting energies to the back collision chamber to build 3^(rd) 3D spectrum,the fragment ion and the decomposition product anion exhibited identical dissociation trajectories when they shared the same molecular geometry.After ginsenosides-focused quantitative metabolomics,significant differences occurred for sub-metabolome amongst different parts of notoginseng.The differential ginsenosides were confirmatively identified by applying the correlations between 3×3D-MS/MS spectra and structures.Together,3×3D-MS/MS spectrum covers all MS/MS behaviors and dramatically facilitates sub-metabolome characterization from both quantitative program development and structural identification. 展开更多
关键词 quantitative submetabolome characterization GINSENOSIDES Structural identification Notoginseng Full exciting energy ramp-MS3 spectrum
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FT-IR跟踪双酚S/环氧氯丙烷醚化反应动力学 被引量:3
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作者 张汇萌 程珏 +3 位作者 尚子扬 于恒 林欣 张军营 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第5期26-31,共6页
采用FT-IR跟踪法研究了双酚S与环氧氯丙烷的醚化反应,使用回归分析法研究了醚化物在FT-IR中的醚键特征峰强度与酚羟基转化率之间的关系,结果表明两者间存在良好的二次函数关系。建立了FT-IR法测定醚化反应中酚羟基转化率的标准工作曲线... 采用FT-IR跟踪法研究了双酚S与环氧氯丙烷的醚化反应,使用回归分析法研究了醚化物在FT-IR中的醚键特征峰强度与酚羟基转化率之间的关系,结果表明两者间存在良好的二次函数关系。建立了FT-IR法测定醚化反应中酚羟基转化率的标准工作曲线,利用该曲线研究了双酚S与环氧氯丙烷的醚化反应动力学,结果表明,在环氧氯丙烷大大过量的情况下,醚化反应速率与酚羟基浓度相关,当酚羟基浓度小于临界浓度时,该反应为一级反应;当酚羟基浓度大于临界浓度时,该反应为零级反应。 展开更多
关键词 双酚S环氧树脂 双酚S 环氧氯丙烷 醚化 ft-ir定量分析
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