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| 1 | Numerical simulation of mechanisms of deformation,failure and energy dissipation in porous rock media subjected to wave stresses显示文摘The pore characteristics,mineral compositions,physical and mechanical properties of the subarkose sandstones were acquired by means of CT scan,X-ray diffraction and physical tests.A few physical models possessing the same pore characteristics and matrix properties but different porosities compared to the natural sandstones were developed.The 3D finite element models of the rock media with varied porosities were established based on the CT image processing of the physical models and the MIMICS software platform.The failure processes of the porous rock media loaded by the split Hopkinson pressure bar(SHPB) were simulated by satisfying the elastic wave propagation theory.The dynamic responses,stress transition,deformation and failure mechanisms of the porous rock media subjected to the wave stresses were analyzed.It is shown that an explicit and quantitative analysis of the stress,strain and deformation and failure mechanisms of porous rocks under the wave stresses can be achieved by using the developed 3D finite element models.With applied wave stresses of certain amplitude and velocity,no evident pore deformation was observed for the rock media with a porosity less than 15%.The deformation is dominantly the combination of microplasticity(shear strain),cracking(tensile strain) of matrix and coalescence of the cracked regions around pores.Shear stresses lead to microplasticity,while tensile stresses result in cracking of the matrix.Cracking and coalescence of the matrix elements in the neighborhood of pores resulted from the high transverse tensile stress or tensile strain which exceeded the threshold values.The simulation results of stress wave propagation,deformation and failure mechanisms and energy dissipation in porous rock media were in good agreement with the physical tests.The present study provides a reference for analyzing the intrinsic mechanisms of the complex dynamic response,stress transit mode,deformation and failure mechanisms and the disaster mechanisms of rock media. | JU Yang1,2,WANG HuiJie1,YANG YongMing1,HU QinAng3 & PENG RuiDong1 1 State Key Laboratory of Coal Resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete,China University of Mining and Technology,Beijing 100083,China 2 Department of Mechanical and Manufacturing Engineering,University of Calgary,Calgary,Alberta,T2N 1N4,Canada 3 School of Environment and Civil Engineering,College of Engineering,Oklahoma State University,Stillwater,OK 74078,USA | 2010 | Science China(Technological Sciences)2010，53，4： | 32 |
| 2 | Energy analysis for damage and catastrophic failure of rocks显示文摘The development history and current state of studies on the characteristics and mechanisms of deformation and failure of rock materials were briefly reviewed from the viewpoint of energy.The main scope and the achievable objectives of the energy-based research system were expatiated.It was validated by experiments that the damage process of rocks can be well described by the rock damage evolution equation established based on energy dissipation.It was found from the uniaxial compression and biaxial compression tests that only a small proportion of the total input energy in hard rocks is dissipated before peak load and a large proportion in soft rocks is dissipated before peak load.For both hard and soft rocks,the energy dissipated after peak load accounts for a greater proportion.More energy would be required for rock failure under equal biaxial compression than under unequal biaxial compression.The total absorbed energy is different for rock failure under high-rate loading and low-rate loading.More fragmented failure pattern usually corresponds to higher energy absorption.The mesoscopic analysis on the damage and failure of bedded salt rocks showed that the energy dissipation is prominent and the total absorbed energy for rock failure is low when cracks propagate in the weak mud interlayer while it is contrary when cracks propagate in the salt rock.The energy accumulation,transfer,dissipation and release during the failure process of tunnel with impending failure under disturbance were analyzed theoretically based on the elastoplastic mechanics theory.Furthermore,the spatial distribution of energy dissipation and energy release of fractured rocks under unloading was simulated numerically.It was demonstrated that energy is likely to be released from the weakest surface under compression,which triggers the global failure of rocks. | XIE HePing 1,2,LI LiYun 2,1,JU Yang 2,PENG RuiDong 2 & YANG YongMing 2 1 Sichuan University,Chengdu 610065,China 2 State Key Laboratory of Coal Resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete,China University of Mining and Technology,Beijing 100083,China | 2011 | Science China(Technological Sciences)2011，54，S1： | 29 |
| 3 | 谷氨酰胺、癌症及其治疗显示文摘目的回顾谷氨酰胺、癌症及其治疗方面的一些进展,主要是关于谷氨酰胺与肿瘤生长方面的体内与体外、动物和人体的研究结果。对荷瘤宿主在接受放疗和化疗时补充谷氨酰胺的某些益处进行总结。背景谷氨酰胺是体内最丰富的游离氨基酸。而肿瘤组织就象一个“谷氨酰胺网”消耗大量的谷氨酰胺,从而促使机体恶病质的发生。体外研究中,肿瘤细胞的生长依赖于谷氨酰胺的结果使得人们未在临床上给癌症病人补充谷氨酰胺。方法对谷氨酰胺与接受放、化疗荷瘤宿主的关系的研究结果进行归纳和总结。结果大量体内研究表明,补充谷氨酰胺不但不会使肿瘤生长,而且还会通过刺激机体的免疫系统来抑制肿瘤的生长。在机体接受放疗和化疗时,谷氨酰胺可以保护机体并增加化疗对肿瘤的选择性。结论还需要进行前瞻、随机的研究来证明在接受放疗和化疗的病人补充谷氨酰胺的安全性和有效性。 | V.Suzanne Klimberg John L.McClellan Little Rock Arkansas | 1999 | 中国临床营养杂志1999，7，2： | 24 |
| 4 | Mineralization episode of porphyry copper deposits in the Jinshajiang-Red River mineralization belt: Re-Os dating显示文摘Re-Os isotopic dating for the molybdenites from the porphyry copper deposits of the Jinshajiang-Red River mineralization belt in Yunnan Province yields isochron ages of 33.9±1.1 Ma for the Machangqing deposit and 34.4±0.5 Ma for the Tongchang deposit. This result shows that both the Machangqing and the Tongchang porphyry Cu-Mo deposits from two different ore-fields formed simultaneously. This new data and the published Re-Os model ages of molybdenite (35.4 Ma, 35.9 Ma, 36.2 Ma) of the Yulong porphyry copper deposit in Tibet, which is located in the same Jinshajiang-Red River mineralization belt as the Machangqing deposit and the Tongchang deposit, suggest that these three Cenozoic porphyry copper deposits in the Jinshajiang-Red River mineralization belt were contemporary for their mineralization episode. That is to say, even their present locality is far away and nearly iso-distantly distributed, these three porphyry Cu(Mo) deposits belong to the same mineralization episode at the end of Eocene. | WANG Denghong, QU Wenjun, LI Zhiwei, YIN Hanlong4 & CHEN Yuchuan Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, China National Center of Rock and Mineral Analysis, Chinese Academy of Geological Sciences, Beijing 100037, China Resource Assessment Center of Yunnan, Kunming 650011, China Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100101, China Chinese Academy of Geological Sciences, Beijing 100037, China | 2005 | Science China Earth Sciences2005，48，2： | 21 |
| 5 | NUMERICAL MODELING FOR COUPLED THERMO-HYDRO-MECHANICAL AND CHEMICAL PROCESSES (THMC) OF GEOLOGICAL MEDIA——INTERNATIONAL AND CHINESE EXPERIENCES显示文摘The coupled thermo-hydro-mechanical and chemical (THMC) processes of stress/deformation,fluid flow,temperature and geochemical reactions of the geological media,namely fractured rocks and soils,play an important role in design,construction,operation and environmental impact assessments of rock and soil engineering works such as underground nuclear waste repositories,oil/gas production and storage,geothermal energy extraction,landslides and slope stability,hydropower and water conservancy complexes,etc. This paper presents an overview of the international and Chinese experiences in numerical modeling of the coupled THMC processes for both the state-of-the-knowledge,remaining challenges and possible future prospects. | Jing Lanru,Feng Xiating (Institute of Rock and Soil Mechanics,The Chinese Academy of Sciences, Wuhan 430071 China) | 2003 | 岩石力学与工程学报2003，22，10： | 17 |
| 6 | Discontinuous deformation analysis based on complementary theory显示文摘The contact between blocks is treated by the open-close iteration in the conventional discontinuous deformation analysis (DDA),which needs to introduce spurious springs between two blocks in contact and to assume the normal stiffness and the tangential stiffness (the penalty factors). Unreasonable values of stiffness would result in numerical problems. To avoid the penalty factors and the open-close iteration,we reformulate the DDA as a mixed complementary problem (MiCP) and then choose the path Newton method (PNM) to solve the problem. Some examples including those originally designed by Shi are reanalyzed,which proves feasibility of the proposed procedure. | ZHENG Hong1,2 & JIANG Wei2 1 China Three Gorges University,Key Laboratory of Geological Hazards on Three Gorges Reservoir Area,Ministry of Education, Yichang 443002,China 2 State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China | 2009 | Science China(Technological Sciences)2009，52，9： | 15 |
| 7 | In situ experiments on width and evolution characteristics of excavation damaged zone in deeply buried tunnels显示文摘The seven long tunnels of Jinping II hydropower station are deeply buried.The width and evolution characteristics of excavation damaged zone(EDZ) are the key problem to the design of tunnels excavation and supports.In order to study this problem,several specific experimental tunnels with different overburden and geometric sizes were excavated at this site.Digital borehole camera,sliding micrometer,cross-hole acoustic wave equipment and acoustic emission apparatus were adopted.This paper introduced the comprehensive in situ experimental methods through pre-installed facilities and pre-drilled boreholes.Typical properties of the surrounding rock mass,including cracks,deformation,elastic wave and micro fractures,were measured during the whole process of the tunnel excavation.The width and characteristics of formation and evolution of tunnels EDZ were analyzed under different construction methods involving of TBM and drilling and blasting,the test tunnels were excavated by full-face or two benches.The relationships between EDZ and tunnel geometry sizes,overburden and excavation method were described as well.The results will not only contribute a great deal to the analysis of rock mass behavior in deeply buried rock mass,but also provide direct data for support design and rockburst prediction. | LI ShaoJun 1,FENG XiaTing 1,LI ZhanHai 3,CHEN BingRui 1,JIANG Quan 1,WU ShiYong 2,HU Bin 2 &XU JinSong 2 1 State Key Laboratory of Geomechanics and Geotechinical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China 2 Ertan Hydropower Development Company,Ltd.,Chengdu 610051,China 3 School of Resources and Civil Engineering,Northeastern University,Shenyang 110004,China | 2011 | Science China(Technological Sciences)2011，54，S1： | 13 |
| 8 | Improvement of GPS ambiguity resolution using prior height information. Part Ⅱ: The method of using quasi observation显示文摘This paper deals with the method of using quasi observation. In the paper a simple algorithm is developed for the adjustment computation with quasi observation at first. And then the ability of quasi observation to improve ambiguity search technique is studied in detail. The robustness of the method is also discussed. A method to determine the weight of quasi observation is proposed. The results show that a prior height can be taken as a quasi observation and used together with GPS observations. It can strengthen residual tests, especially in situation where there are fewer satellites in the sky. It also can change structure of incorrect solutions, which will theoretically make less incorrect solutions left in search space. At last the field tests are carried out to show that the proposed method is effective. The success rate of ambiguity resolution in the four field tests is improved significantly. | 朱建军 Rock Santerre | 2002 | Journal of Central South University of Technology2002，9，4： | 12 |
| 9 | Thermal-mechanical coupled effect on fracture mechanism and plastic characteristics of sandstone显示文摘Scanning electronic microscopy (SEM) was employed to investigate fractographs of sandstone in mine roof strata under thermal-mechanical coupled effect. Based on the evolution of sandstone surface morphology in the failure process and frac- tography, the fracture mechanism was studied and classified under meso and mi- cro scales, respectively. The differences between fractographs under different tem- peratures were examined in detail. Under high temperature, fatigue fracture and plastic deformation occurred in the fracture surface. Therefore, the temperature was manifested by these phenomena to influence strongly on micro failure mechanism of sandstone. In addition, the failure mechanism would transit from brittle failure mechanism at low temperature to coupled brittle-ductile failure mechanism at high temperature. The variation of sandstone strength under differ- ent temperature can be attributed to the occurrence of plastic deformation, fatigue fracture, and microcracking. The fatigue striations in the fracture surfaces under high temperature may be interpreted as micro fold. And the coupled effect of tem- perature and tensile stress may be another formation mechanism of micro fold in geology. | ZUO JianPing1,2, XIE HePing2,3, ZHOU HongWei1,2 PENG SuPing1 1 State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083, China 2 Institute of Rock Mechanics and Fractals, China University of Mining and Technology, Beijing 100083, China 3 Sichuan University, Chengdu 610065, China | 2007 | Science China(Technological Sciences)2007，50，6： | 11 |
| 10 | 硫化物矿物标准物质的研制显示文摘研制的黄铁矿、黄铜矿、方铅矿和闪锌矿4个标准物质是国内首次成功研制的硫化物矿物成分分析标准物质。样品采用重选、磁选和电磁选等选矿技术提纯矿物,获得纯度大于95%的单矿物样品。黄铁矿和闪锌矿用棒磨机少量多级粉碎至0.147mm,方铅矿和黄铜矿用小型玛瑙球磨机粉碎至0.097mm。经单因素方差分析检验,均匀性符合要求。采用小包装在干燥、充氩气气氛中保存样品,使样品稳定性有足够保证。连续4年定期监测了样品中全硫含量,证明稳定性良好。样品由国内经计量认证的5家实验室采用多种分离富集手段、不同原理方法协同分析。标准值的确定依据数据分布特征而定,对于服从正态分布的元素,用算术平均值作为定值,对不服从正态分布的元素用多参数模式定值。共确定了56个标准值,16个参考值,6个信息值。该批标准物质于1994年12月通过了国家标准物质研究中心组织的专家复审,并于1995年4月被国家技术监督局批准为国家一级标准物质,标准号分别为GBW07267(GSM-1)、GBW07268(GSM-2)、GBW07269(GSM-3)、GBW07270(GSM-4)。 | (InstItute of Rock and Mineral Analysis,Ministry of Geology and Mineral Resources,Beijing,100037) | 1995 | 岩矿测试1995，14，2： | 11 |
| 11 | One-step disposal of Cr (Ⅵ)-bearing wastewater by natural pyrrhotite显示文摘Cr(Ⅵ)-bearing wastewater can be treated by natural pyrrhotite which is used for reductant to reduce Cr(Ⅵ) and precipitant to precipitate Cr(Ⅲ) simultaneously. The disposal products can be divided into three parts in the beakers, namely supernatant in the upper part, the yellowish colloidal precipitates in the middle part and the pyrrhotite in the lower part. The content of total Cr=Cr(Ⅵ)+Cr(Ⅲ) in the supernatant liquid is 0.06 mg/L, which is lower than 1.5 mg/L of the discharge standard of China and near to 0.05 mg/L of the standard of potable water. This one-step disposal composing of both reduction and precipitation which is traditionally divided into two independent steps called reducing technology and precipitating technology respectively. The new method is of obvious economic advantage and favourable to decreasing surplus mud derived from adding Ca(OH)2 to precipitate Cr(Ⅲ) traditionally so as to avoid recontamination. In fact, sodium sulfite (Na2SO3) used in disposal of Cr(Ⅵ) was | LU Anhuai, CHEN Jie, SHI Junxian, LU Xiaoying, TANG Junli & GUO Min1. Departmenl of Geology, Peking University, Beijing 100871, China 2. National Laboratory of Mineral and Rock Materials, China University of Geosciences, Beijing 100083, China (e-mail: luanhuai | 2000 | Chinese Science Bulletin2000，45，17： | 9 |
| 12 | 岩石标准物质的研制显示文摘研制了霓霞正长岩、粗面岩、花岗闪长岩、辉长岩、流纹岩及白云岩6种不同类型的岩石标准物质。对用X射线荧光光谱法均匀性检验的实际取样量进行了探讨。选择分析测试方法时,除采用了标准方法和长期应用的分析方法外,还采用了近年发展起来的新技术新方法。在定值中应用了多参数统计定值模式,给出了69个元素的标准值和参考值。该批标准物质于1991年1月经国家技术监督局审核批准为国家一级标准物质,编号分别为GBW07109(GSR-7)、GBW07110(GSR-8)、GBW07111(GSR-9)、GBW07112(GSR-10)、GBW07113(GSR-11)、CBW07114(GSR-12)。 | (Institute of Rock and Mineral Analysis,Ministry of geology and mineral Resources,Beijing,100037) | 1995 | 岩矿测试1995，14，2： | 9 |
| 13 | Experimental study of dynamic mechanical properties of reactive powder concrete under high-strain-rate impacts显示文摘The dynamic mechanical properties of reactive powder concrete subjected to compressive impacts with high strain rates ranging from 10 to 1.1×102 s-1 were investigated by means of SHPB (split-Hopkinson-pressure-bar) tests of the cylindrical specimens with five different steel fiber volumetric fractions.The properties of wave stress transmission,failure,strength,and energy consumption of RPC with varied fiber volumes and impact strain rates were analyzed.The influences of impact strain rates and fiber volumes on those properties were characterized as well.The general forms of the dynamic stress-strain relationships of RPC were modeled based on the experimental data.The investigations indicate that for the plain RPC the stress response is greater than the strain response,showing strong brittle performance.The RPC with a certain volume of fibers sustains higher strain rate impact and exhibits better deformability as compared with the plain RPC.With a constant fiber fraction,the peak compressive strength,corresponding peak strain and the residual strain of the fiber-reinforced RPC rise by varying amounts when the impact strain rate increases,with the residual strain demonstrating the greatest increment.Elevating the fiber content makes trivial contribution to improving the residual deformability of RPC when the impact strain rate is constant.The tests also show that the fiber content affects the peak compressive strength and the peak deformability of RPC in a different manner.With a constant impact strain rate and the fiber fraction less than 1.75%,the peak compressive strength rises with an increasing fiber volume.The peak compressive strength tends to decrease as the fiber volume exceeds 1.75%.The corresponding peak strain,however,incessantly rises with the increasing fiber volume.The total energy Edisp that RPC consumed during the period from the beginning of impacts to the time of residual strains elevates with the fiber volume increment as long as the fiber fraction is not larger than 2%.It turns to decrease if the fiber volume exceeds 2%.The added fibers make various contributions to enhancing the capability of RPC to consume energy at different loading stages.If the fiber fraction is not larger than 2%,the added fibers make more contribution to enhancing the energy consumption ability of RPC in the period before the peak strain than in the period after the peak strain.The impact strain rate,however,distinctively affects the total energy that RPC consumed and the energy consumed in the different loading periods.The higher the impact strain rate,the more the energy consumed in the stages and therefore the higher the dynamic impact toughness.The empirical relationships of the peak compressive strength,corresponding peak strain,residual strain,total consumed energy and the energy consumed in the varied periods with the impact strain rate and the fiber fraction are derived.Four generalized forms of the dynamic impact stress-strain responses of RPC are formulated by normalizing stresses and strains as the generalized coordinates and by taking account of the influences of impact strain rates and fiber volumetric fractions. | JU Yang1,2,LIU HongBin1,SHENG GuoHua1,3 & WANG HuiJie1 1 State Key Laboratory of Coal Resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete,China University of Mining and Technology,Beijing 100083,China 2 Department of Mechanical and Manufacturing Engineering,University of Calgary,2500 University Drive,AB T2N 1N4,Canada 3 School of Resources and Civil Engineering,Northeastern University,Shenyang 110004,China | 2010 | Science China(Technological Sciences)2010，53，9： | 8 |
| 14 | 3D thermo-hydro-mechanical-migratory coupling model and FEM analyses for dual-porosity medium显示文摘One kind of 3D coupled thermo-hydro-mechanical-migratory model for saturated-unsaturated dual-porosity medium was established,in which the stress field and the temperature field are single,but the seepage field and the concentration field are double,and the influences of sets,spaces,angles,continuity ratios,stiffness of fractures on the constitutive relationship of the medium can be considered.The relative three-dimensional program of finite element method was also developed.By comparing with the existing computation example,reliability of the model and the program were verified.Taking a hypothetical nuclear waste repository as a calculation example,the radioactive nuclide leak was simulated numerically with both the rock mass and the buffer being unsaturated media,and the temperatures,negative pore pressures,flow velocities,nuclide concentrations and normal stresses in the rock mass were investigated.The results showed that the temperatures,negative pore pressures and nuclide concentrations in the buffer all present nonlinear changes and distributions that even though the saturation degree in porosity is only about 1/9 of that in fracture,the flow velocity of underground water in fracture is about 6 times of that in porosity because the permeability coefficient of fracture is almost four orders higher than that of porosity,and that the regions of stress concentration occur at the vicinity of two sides of the boundary between buffer and disposal pit wall. | ZHANG YuJun 1&ZHANG WeiQing 2 1 State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics, Chinese Academy of Sciences,Wuhan 430071,China 2School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China | 2010 | Science China(Technological Sciences)2010，53，8： | 8 |
| 15 | A Study of the Rhenium-Osmium Geochronometry of Molybdenites显示文摘This study deals with the first application of the isotope dilution - inductively coupled plasma mass spectrometry in the rhenium-osmium geochronometry in China. The chemical separation procedure included decomposition of samples by means of alkali fusion, extraction of rhenium by acetone and extraction of osmium by distillation. The recovery of both elements in the entire process was more than 90% . The blanks of analyses were 0.07 ng for rhenium and 0.01 ng for 187Os. The mineralization ages of molybdenites from four molybdenum deposits in China were determined by using this method, with a precision (2σ)of about ±3% . These results agree satisfactorily with their geological backgrounds. The Re-Os method can directly determine ages of metal deposits and reflect the true ages more reliably than other dating methods that only determine the ages of country rocks from which mineralization ages are inferred. As many hydrothermal sulphide deposits usually contain molybdenites, this method has bright | Du Andao, He Hongliao, Yin Ningwan, Zou Xiaoqiu,Sun Yali, Sun Dezhong, Chen Shaozhen and Qu Wenjun Institute of Rock and Mineral Analysis, Chinese Academy of Geological Sciences, Beijing Fei Zhenbi | 1995 | Acta Geologica Sinica(English Edition)1995，69，2： | 7 |
| 16 | Distribution of ^3H—nicotine in Rat Tissues Under the Influence of Simulated Microgravity显示文摘Rat tail suspension offers a useful model to reproduce physiologic responses to weightlessness.The present study was conducted in the head-down-tilt(HDT) rat model to assess changes in metabolism of body tissues employing 3H-nicotine. Twelve male rats were used in the study. Half of the rats were tail suspended at 30°for two weeks on a 12/12 light/dark cycle. During this period,body weight, food and fluid intakes were measured. At term, animals were anesthetized and injected IV withe a solution contaming 4 microuries of micotine. After 90 min the animals were sacrificed, exsanguinated and tissues (brain,blood,trachea,salivary gland,lung,heart,esophagus,spleen, kidneys and testes) were harvested. The distribution of 3H-nicotine per gram of each tissue was determinded and ealeulated as percent of total injected radioactivity. Final body weights of suspended ammals were significantly (P < 0.0 5) lower than those of eontrols(309±21 vs 350±11g). 3HNicotine waw retained in greatest amounts by the kindneys, followed inorder by salivary glands, spleen, and gastrointestinal tissues. compared to non-suspended control, the tissue retention of nicotine in suspended animals was decreased in the following tissues:esphyagus (25 %), aorta (25%). fundus (25%), trachea (22%), adrenals (18%), spleen (17 %), and pancreas (12 %). The decreased retention of mcotine in tissues from suspended animals may be indicative of the fluid shifts and changes in blood flow to those tissue beds. The lack of differnces in nicotine retention in liver and kidney between control and suspended groups may implicate a normal metabolic function of these organs even under simulated weightlessness. | PARIMAL CHOWDHURY MICHAEL E. SOULSBY AND JAMES N. PASLEY (Department of Physiology and Biophysics, University of Arkansas for Medical Scienses, Little Rock, Arkansas 72205, USA) | 1999 | Biomedical and Environmental Sciences1999，12，2： | 6 |
| 17 | Experimental Investigation of the Flame Propagation and Flashback Behavior of a Green Propellant Consisting of N2O and C2H4显示文摘 | Lukas Werling Felix Lauck Dominic Freudenmann Nicole Rocke Helmut Ciezki Stefan Schlechtriem | 2017 | Journal of Energy and Power Engineering2017，11，12： | 6 |
| 18 | Study on mechanical parameters of fractured rock masses显示文摘The equivalent strength parameters of fractured rock masses are prerequisite for stability analysis of geotechnical engineering projects constructed in fractured rock masses which are encountered frequently in western china.Based on generated mesh of fractured rock masses,combined with statistic damage constitutive model of intact rock and damage model of structural plane,progressive failure of fractured rock masses is studied using finite element method(FEM) .Furthermore,Scale effect and anisotropy of compressive strength of fractured rock masses are studied.Study results show that the strength decreases and tend towards stability rapidly from intact rock to fractured rock masses,and the anisotropy of strength of fractured rock masses is not significant.At last,based on numerical simulation conducted on 10 m scale rock masses under different confining pressures,the equivalent strength parameters of fractured rock masses are gained and the results are compared with Hoek-Brown criteria.The method developed is helpful for determination of strength parameters of fractured rock masses. | CHEN WeiZhong 1,2,YANG JianPing 1,TAN XianJun 1 &YU HongDan 1 1 State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China 2 Research Center of Geotechnical and Structural Engineering,Shandong University,Jinan 250061,China | 2011 | Science China(Technological Sciences)2011，54，S1： | 5 |
| 19 | Colonic manifestations of PTEN hamartoma tumor syndrome: Case series and systematic review显示文摘AIM:To investigate our clinical experience with the colonic manifestations of phosphatase and tensin homolog on chromosome ten(PTEN)hamartoma tumor syndrome(PHTS)and to perform a systematic literature review regarding the same.METHODS:This study was approved by the appropriate institutional review board prior to initiation.A clinical genetics database was searched for patients with PHTS or a component syndrome that received gastrointestinal endoscopy or pathology interpretation at our center.These patient’s records were retrospectively reviewed for clinical characteristics(including family history and genetic testing),endoscopy results and pathology findings.We also performed a systematic review of the literature for case series of PHTS or component syndromes that reported gastrointestinal manifestations and investigations published after consensus diagnostic criteria were established in 1996.These results were compiled and reported.RESULTS:Eight patients from our institution met initial inclusion criteria.Of these,5 patients underwent4.2 colonoscopies at mean age 45.8±10.8 years.All were found to have colon polyps during their clinical course and polyp histology included adenoma,hyperplastic,ganglioneuroma and juvenile.No malignant lesions were identified.Two had multiple histologic types.One patient underwent colectomy due to innumerable polyps and concern for future malignant potential.Systematic literature review of PHTS patients undergoing endoscopy revealed 107 patients receiving colonoscopy at mean age 37.4 years.Colon polyps were noted in92.5%and multiple colon polyp histologies were reported in 53.6%.Common polyp histologies included hyperplastic(43.6%),adenoma(40.4%),hamartoma(38.3%),ganglioneuroma(33%)and inflammatory(24.5%)polyps.Twelve(11.2%)patients had colorectal cancer at mean age 46.7 years(range 35-62).Clinical outcomes secondary to colon polyposis and malignancy were not commonly reported.CONCLUSION:PHTS has a high prevalence of colon polyposis with multiple histologic types.It should be considered a mixed polyposis syndrome.Systematic review found an increased prevalence of colorectal cancer and we recommend initiating colonoscopy for colorectal cancer surveillance at age 35 years. | Peter P Stanich Robert Pilarski Jonathan Rock Wendy L Frankel Samer El-Dika Marty M Meyer | 2014 | World Journal of Gastroenterology2014，20，7： | 5 |
| 20 | Slope safety control during mining below a landslide显示文摘The East Open Pits of Daye Iron Mine were closed in year 2000 and the ore beyond the pit limit was planned to be mined by underground ways. In order to facilitate the smooth transition to underground mining, hanging-wall ores in the old pits were scheduled to be mined. Xiangbishan pit is one of the four mining spots selected. In 1979 when the pit was mined to around 36 m a.s.l., a landside of around 70000 m3 occurred in its North Slope, leading to the closure of the pit. The pit was then backfilled to 60 m a.s.l. to maintain the slope stability. The hanging-wall ore to be mined is just located below the old slide, so whether the slide will be reactivated and how to control its deformation and stability are the key issues concerned. Based on geological investigation and numerical analysis, it was predicted that the slide would be reactivated and a control measure using the intact ore body as a retaining wall was thus suggested. During mining, displacements were monitored to assure safety. By July, 2003, 383000 tons of ore were successfully mined. Though the observed displacement reached 8795 mm, no major failure happened. The final slope is 110 m high with an angle of 70°. | MIN Hong1, DENG Jianhui1, WEI Jinbing1, ZHANG Qizhong2, ZOU Jiangang2 & ZHOU Zhibin2 1. Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China 2. Daye Iron Mine of WISCO, Tieshan, Daye 435006, China | 2005 | Science China(Technological Sciences)2005，48，z1： | 5 |
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