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New true-triaxial rock strength criteria considering intrinsic material characteristics

Acta Mechanica Sinica 2018年第1期34卷 130-142页

作者： Qiang Zhang Cheng Li Xiaowei Quan Yanning wang Liyuan Yu binsong Jiang State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil Engineering China University of Mining and Technology

A reasonable strength criterion should reflect the hydrostatic pressure effect, minimum principal stress effect,and intermediate principal stress effect. The former two effects can be described by the meridian curves, and the last one mainly depends on the Lode angle dependence function. Among three conventional strength criteria, ***–Coulomb(MC), Hoek–Brown(HB), and Exponent(EP) criteria, the difference between generalized compression and extension strength of EP criterion experience a firstly increase then decrease process, and tends to be zero when hydrostatic pressure is big enough. This is in accordance with intrinsic rock strength characterization. Moreover, the critical hydrostatic pressure Icorresponding to the maximum difference of between generalized compression and extension strength can be easily adjusted by minimum principal stress influence parameter K. So, the exponent function is a more reasonable meridian curves, which well reflects the hydrostatic pressure effect and is employed to describe the generalized compression and extension ***, three Lode angle dependence functions of L,L, and L, which unconditionally satisfy the convexity and differential requirements, are employed to represent the intermediate principal stress effect. Realizing the actual strength surface should be located between the generalized compression and extension surface, new true-triaxial criteria are proposed by combining the two states of EP criterion by Lode angle dependence function with a same lode angle. The proposed new true-triaxial criteria have the same strength parameters as EP criterion. Finally, 14 groups of triaxial test data are employed to validate the proposed criteria. The results show that the three new true-triaxial exponent criteria,especially the Exponent Willam-Warnke criterion(EPWW)criterion, give much lower misfits, which illustrates that the EP criterion and Lhave more reasonable meridian and deviatoric function form, respectively.

关键词： Rock Strength criterion Meridian plane Lode angle dependence Convexity

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Analytical solution for stress and deformation of the mining floor based on integral transform

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International Journal of Mining Science and Technology 2015年第4期25卷 581-586页

作者： Feng Qiang Jiang binsong State Key Laboratory of Geomechanics and Deep Underground Engineering China University of Mining & Technology Civil Engineering and Architecture Shandong Key Laboratory of Civil Engineering Disaster Prevention & Mitigation Shandong University of Science and Technology

Following exploitation of a coal seam, the final stress field is the sum of in situ stress field and an excavation stress field. Based on this feature, we firstly established a mechanics analytical model of the mining floor strata. Then the study applied Fourier integral transform to solve a biharmonic equation,obtaining the analytical solution of the stress and displacement of the mining floor. Additionally, this investigation used the Mohr–Coulomb yield criterion to determine the plastic failure depth of the floor strata. The calculation process showed that the plastic failure depth of the floor and floor heave are related to the mining width, burial depth and physical–mechanical properties. The results from an example show that the curve of the plastic failure depth of the mining floor is characterized by a funnel shape and the maximum failure depth generates in the middle of mining floor; and that the maximum and minimum principal stresses change distinctly in the shallow layer and tend to a fixed value with an increase in depth. Based on the displacement results, the maximum floor heave appears in the middle of the stope and its value is 0.107 m. This will provide a basis for floor control. Lastly, we have verified the analytical results using FLAC3 Dto simulate floor excavation and find that there is some deviation between the two results, but their overall tendency is consistent which illustrates that the analysis method can well solve the stress and displacement of the floor.

关键词： Integral transform Mining floor Plastic failure depth Floor heave Analytical solution

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医疗废物管理对环境影响的初探

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环境科学与管理 2017年第8期42卷 10-13页

作者：王蕾赵娜王滨松苑晨邢子鹏刘杨郑晟良哈尔滨市环境工程评估中心黑龙江哈尔滨150021 黑龙江大学化学化工与材料学院黑龙江哈尔滨150080

医疗废物的传染性可能对人类和环境造成不良影响,因此医疗废物管理是非常重要的。首先概述了医疗废物处理在各国的立法情况,以及医疗废物的收集和分类情况,进一步讨论了焚烧和高压釜处理医疗废物方法的优缺点,焚烧会造成二恶英、呋喃和... 详细信息

医疗废物的传染性可能对人类和环境造成不良影响,因此医疗废物管理是非常重要的。首先概述了医疗废物处理在各国的立法情况,以及医疗废物的收集和分类情况,进一步讨论了焚烧和高压釜处理医疗废物方法的优缺点,焚烧会造成二恶英、呋喃和汞排放,造成不利的健康和环境影响,而高压釜处理不能处理所有类型的医疗废物。控制医疗废物的最佳手段是减少产生量,可以通过对医护人员进行良好的培训以及实施标准化医疗废物分类和收集来实现,并研究改进传染性医疗废物处理方法。

关键词：医疗废物传染废物立法处理

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An improved strain-softening constitutive model of granite considering the effect of crack deformation

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1202-1215页

作者： Yapeng Li Qiang Zhang Qiuxin Gu Peinan Wu binsong Jiang State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou221116China

This paper presents an improved strain-softening constitutive model considering the effect of crack deformation based on the triaxial cyclic loading and unloading test *** improved model assumes that total strain is a combination of plastic,elastic,and crack *** constitutive relationship between the crack strain and the stress was further *** evolutions of mechanical parameters,*** parameters,dilation angle,unloading elastic modulus,and deformation parameters of crack,with the plastic strain and confining pressure were *** the increase in plastic strain,the cohesion,friction angle,dilation angle,and crack Poisson's ratio initially increase and subsequently decrease,and the unloading elastic modulus and the crack elastic modulus nonlinearly *** increasing confining pressure enhances the strength and unloading elastic modulus,and decreases the dilation angle and Poisson's ratio of the *** theoretical triaxial compressive stress-strain curves were compared with the experimental results,and they present a good agreement with each *** improved constitutive model can well reflect the nonlinear mechanical behavior of granite.

关键词： Strain-softening Crack deformation effect Plastic shear strain Constitutive model

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Synthesis and photocurrent response of porphyrin-containing conjugated polymers

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Chinese Science Bulletin 2006年第11期51卷 1287-1295页

作者： ZHAO Jinling LI binsong B0 Zhishan State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Porphyrin-containing conjugated poly- mers with fluorene or carbazole as spacer groups were prepared by Sonogashira cross-coupling reac- tions. The polymers were of high molecular weight and the flexible alkyl chains on fluorene or carbazole units made the conjugated polymers soluble in common organic solvents, such as THF and methyl- ene chloride. The polymers could form high quality durable films from solution casting. Their optical and photocurrent responsive properties were investigated. It was found that the photocurrent response was di- rectly proportional to the content of porphyrin. The incorporation of carbazole units into the polymer chains also gave positive contribution to the photo- current generation in some extent.

关键词：卟啉共轭聚合物光电流响应合成

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Single-level dynamic spiral CT of hepatocellular carcinoma:Correlation between imaging features and density of tumor microvessels

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World Journal of Gastroenterology 2004年第1期10卷 67-72页

作者： Wei-XiaChen Peng-QiuMin binsong Bong-LiangXiao YanLiu Ying-HuiGe DepartmentofRadiology WestChinaHospitalSichuanUniversityChengdu610041SichuanProvinceChina DepartmentofToxicologyandPathology SchoolofPublicHealthSichuanUniversityCh-engdu610041SichuanProvinceChina DepartmentofRadiology WestChinaHospitalSichuanUniversitynowworkinginRijinHospitalShanghaiChina DepartmentofRadiology WestChinaHospitalSichuanUniversitynowworkinginHenanProvinceHospitalHenanProvinceChina

AIM: To investigate the correlation of enhancement features of hepatocellular carcinoma (HCC) revealed by single-level dynamic spiral CT scanning (DSCT) with tumor microvessel density (NVD), and to determine the validity of DSCT in assessing in vivo tumor angiogenic activity of HCC. METHODS: Twenty six HCC patients were diagnosed histopathologically. DSCT was performed for all patients according to standard scanning protocol. Time-density curves were generated, relevant curve parameters were measured,and gross enhancement morphology was analyzed. Operation was performed to remove HCC lesions i to 2 weeks following CT scan. Histopathological slides were carefully prepared for the standard F8RA immunohistochemical staining and tumor microvessel counting. Enhancement imaging features of HCC lesions were correlatively studied with tumor MVD and its intra-tumor distribution characteristics. RESULTS: On DSCT images of HCC lesions, three patterns of time-density curve and three types of gross enhancement morphology were recognized. Histomorphologically, the distribution of positively stained tumor endothelial cells within tumor was categorized into 3 types. Curve parameters such as peak enhancement value and contrast enhancement ratio were significantly correlated with tumor tissue MVD (/=0.508 and /=0.423, P<0.01 and P<0.05 respectively). Both the pattern of time-density curve and the gross enhancement morphology of HCC lesions were also correlated with tumor MVD, and reflected the distributive features of tumor microvessels within HCC lesions. Correlation between the likelihood of intrahepatic metastasis of HCC lesions with densely enhanced pseudocapsules and rich pseudocapsular tumor MVD was ***: Enhancement imaging features of HCC lesions on DSCT scanning are correlated with tumor MVD,and reflect the intra-tumor distribution characteristics of tumor microvessels. DSCT is valuable in assessing the angiogenic activity and tumor neovascularity of HCC patients

关键词：动态螺旋CT 肝细胞癌微血管密度影像学诊断

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Adhesion of different cell cycle human hepatoma cells to endothelial cells and roles of integrin β_1

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World Journal of Gastroenterology 2005年第2期11卷 212-215页

作者： Guan-binsong JianQin QingLuo Xiao-DongShen Run-BinYan Shao-XiCai KeyLaboratoryforBiomechanicsandTissueEngineeringoftheStateMinistryofEducation CollegeofBioengineeringChongqingUniversityChongqing400044China

AIM: To investigate the adhesive mechanical properties of different cell cycle human hepatoma cells (SMMC-7721) to human umbilical vein endothelial cells (ECV-304), expression of adhesive molecule integrinβ1 in SMMC-7721 cells and its contribution to this adhesive course. METHODS: Adhesive force of SMMC-7721 cells to endothelial cells was measured using micropipette aspiration technique. Synchronous G1 and S phase SMMC-7721 cells were achieved by thymine-2-deoxyriboside and colchicines sequential blockage method and double thymine-2-deoxyriboside blockage method, respectively. Synchronous rates of SMMC-7721 cells and expression of integrinβ1 in SMMC-7721 cells were detected by flow cytometer. RESULTS: The percentage of cell cycle phases of general SMMC-7721 cells was 11.01% in G2/M phases, 53.51% in G0/G1 phase, and 35.48% in S phase. The synchronous rates of G1 and S phase SMMC-7721 cells amounted to 74.09% and 98.29%, respectively. The adhesive force of SMMC-7721 cells to endothelial cells changed with the variations of adhesive time and presented behavior characteristics of adhesion and de-adhesion. S phase SMMC-7721 cells had higher adhesive forces than d phase cells [(307.65±92.10)×10-10N vs(195.42±60.72)×10-10N, P<0.01]. The expressive fluorescent intensity of integrinβ1 in G1 phase SMMC-7721 cells was depressed more significantly than the values of S phase and general SMMC-7721cells. The contribution of adhesive integrinβ1 was about 53% in this adhesive course. CONCLUSION: SMMC-7721 cells can be synchronized preferably in d and S phases with thymine-2-deoxyriboside and colchicines. The adhesive molecule integrinβ1 expresses a high level in SMMC-7721 cells and shows differences in various cell cycles, suggesting integrin β1 plays an important role in adhesion to endothelial cells. The change of adhesive forces in different cell cycle SMMC-7721 cells indicates that S phase cells play predominant roles possibly while they interact with endothelial cells.

关键词： Hepatoma Cell cycle Integrin β1 Endothelial cells Cell adhesion

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Enhancement of two-photon absorption cross section and singlet-oxygen generation in porphyrin-cored star polymers

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Science China Chemistry 2009年第1期52卷 56-63页

作者： WAN Yan JIA Ke LI binsong BO ZhiShan XIA AnDong State Key Laboratory of Molecular Reaction Dynamics and Beijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing 100080China State Key Laboratory of Polymer Physics and Chemistry and Beijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing 100080China

We report a newly synthesized polymer of a star-shaped porphyrin compound(TPA-FxP) with four oligofluorene arms at its meso positions with the pronounced enhancement of the two-photon properties and the generation of singlet oxygen by utilizing the two-photon excited fluorescence resonance energy *** steady-state spectra and transient triplet-triplet absorption spectra give evidence that the enhanced two-photon absorption cross section results from not only the through-space energy transfer(Frster) but also the through-bond energy transfer between conjugated peripheral oligofluorene arms and the porphyrin *** two-photon absorption cross section at 780 nm up to 3360 GM(1 GM = 10-50 cm4·s/photon) of TPA-FxP was obtained,which is comparable to the highest values reported from other similar chemically modified porphyrin core ***,the enhanced production of singlet oxygen under two-photon absorption conditions is also reported.

关键词： porphyrin-cored star polymer two-photon excitation energy transfer

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DETERMINATION OF DEGREE OF CRYSTALLINITY OF NYLON 1212 BY WIDE-ANGLE X-RAY DIFFRACTION

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Chinese Journal of Polymer Science 2004年第5期22卷 491-496页

作者： Jian-binsong Min-qiaoRen Qing-yongChen Shu-yunwang Qing-xiangZhao Hong-fangZhang 莫志深 StateKeyLaboratoryofPolymerPhysicsandChemistry ChangchunInstituteofAppliedChemistryChineseAcademyofSciencesChangchun130022China CollegeofMaterialsEngineering Zhengzhou-UniversityZhengzhou450052China

Based on the X-ray scattering intensity theory and using the approximate expression for the atomic scattering factor, the correction factors for three crystalline peaks and an amorphous peak of Nylon 1212 were calculated and the formula of degree of crystallinity of Nylon 1212 was derived by a graphic multipeak resolution method. The degree of crystallinity calculated from the WAXD method is compatible with those obtained by density and calorimetry methods.

关键词： Degree of crystallinity WAXD Nylon 1212

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Testing mechanisms underlying elevational patterns of lakeshore plant community assembly in Poyang Lake, China

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Journal of Plant Ecology 2019年第3期12卷 438-447页

作者： Zhichun Lan Yasong Chen Lei Li Feng Li binsong Jin Jiakuan Chen Jiangxi Province Key Laboratory of Watershed Ecosystem Change and Biodiversity Center for Watershed EcologyInstitute of Life ScienceSchool of Life SciencesNanchang UniversityNanchang 330031China Coastal Ecosystems Research Station of the Yangtze River Estuary Ministry of Education Key Laboratory for Biodiversity Science and Ecological EngineeringSchool of Life SciencesFudan UniversityShanghai 200438China Key Laboratory of Watershed Ecology and Geographical Environment Monitoring NASGNanchang 330029China Key Laboratory of Poyang Lake Environment and Resource Utilization Ministry of EducationNanchang UniversityNanchang 330031China National Ecosystem Research Station of Jiangxi Poyang Lake Wetland Nanchang 330038China Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China

Aims Plant community assembly in wetlands usually changes with eleva-tion gradients,which may be due to the direct effect of flooding and indirect effects such as changes in soil properties and ***,the respective importance of each factor remains to be *** We investigated patterns of plant diversity,community biomass and soil properties along an elevation gradient of a lakeshore meadow at Poyang Lake,*** Findings(i)With increasing elevation,species richness and Simpson diver-sity index *** aboveground biomass(AGB)and below-ground biomass(BGB)increased with elevation,however,the BGB/AGB ratio also increased,which suggests a significant effect of belowground competition.(ii)Soil N content and soil N:P ratio increased,whereas soil pH decreased with *** soil properties showed no significant response.(iii)Structural equa-tion modeling showed that variation of plant diversity was mainly explained by ***,intensified belowground competition seems to be the primary mechanism causing lower plant diversity at higher elevations.(iv)These findings were further supported by the observed greater response ratio of N and P storage in plant commu-nities than the response ratio of soil N and P content to elevation,suggesting that soil nutrient limitation and belowground nutrient competition increased with *** study has important implications to wetland management and biodiversity conserva-tion under environmental change(*** in flooding regimes,eutrophication).

关键词： belowground competition aboveground competition flooding tolerance nutrient limitation biomass allocation

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