|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | 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 |
| 2 | Revisiting the methods for gas permeability measurement in tight porous medium显示文摘Permeability is a key parameter to describe fluid transport properties of porous medium; however, the permeability measurement is extremely difficult for tight porous medium, e.g. fine-grained rock or dense soil. In this paper, three methods for gas permeability measurement, i.e. steady state method, pulse decay method(PDM) and pressure oscillation method(POM), are first reviewed and then their advantages and drawbacks are discussed. Both analytical and numerical solutions of gas permeability are presented for the tight porous medium. The results show that the analytical method is relatively simple but only valid under certain conditions, whilst the numerical method is more robust and generic, which can take into account several factors such as porosity, saturation, gas leakage, and unconventional boundary conditions. The influence of the effective porosity on the permeability determination is further analyzed using the proposed numerical method. In this study, new pressure data interpretation procedures for PDM and POM are proposed, and the obtained results can serve as a guidance to define a proper method for permeability measurement of the tight porous medium. | Diansen Yang Wei Wang Weizhong Chen Xianjun Tan Lige Wang | 2019 | Journal of Rock Mechanics and Geotechnical Engineering2019，11，2： | 3 |
| 3 | A fully coupled thermo-hydro-mechanical model for unsaturated porous media显示文摘In examining potential host rocks for such purposes as the disposal of high-level radioactive wastes,it is important to understand the coupled thermo-hydro-mechanical(THM) behavior of a porous medium.A rigorous and fully unified coupled thermo-hydro-mechanical model for unsaturated porous media is required to simulate the complex coupling mechanisms involved.Based on modified Darcy's and Fourier's laws,equations of mechanical equilibrium,mass conservation and energy conservation are derived by introducing void ratio and volumetric liquid water content into the model.The newly derived model takes into account the effects of temperature on the dynamic viscosity of liquid water and void ratio,the influence of liquid flow on temperature gradient(thermo-osmosis),the influence on mass and heat conservation equations,and the influence of heat flow on water pressure gradient and thermal convection.The new coupled THM constitutive model is constructed by a finite element program and is used to simulate the coupled behavior of a tunnel during excavation,ventilation and concrete lining stages.Oil and gas engineering,underground disposal of nuclear waste and tunnel engineering may be benefited from the development of the new model. | Weizhong Chen Xianjun Tan Hongdan Yu Guojun Wu Shanpo Jia | 2009 | Journal of Rock Mechanics and Geotechnical Engineering2009，1，1： | 3 |
| 4 | Direct conversion of methane to methanol over Cu exchanged mordenite:Effect of counter ions显示文摘Direct conversion of methane(CH4)to methanol(DMTM)is a promising,but very challenging process for the utilization of abundant CH4 as a low carbon resource.In this context,Cu loaded zeolites,mordenite(MOR)in particular,were recognized as the most effective system to perform DMTM.In this work,different Cu salts were used to exchange with MOR,by which the effect of counter ions on the catalytic performance towards DMTM was investigated.The prepared catalysts were characterized and evaluated systematically.It was found that the counter ions affected the speciation of Cu sites,probably due to their capability in extraction of protons from MOR and the influence on the hydrolysis state of the Cu2+in aqueous solution.These behaviors adjusted the association between Cu2+and the exchangeable protons in MOR.As a result,varied DMTM performance was observed.Among the used Cu salts,Cu(CH3COO)2 exchanged MOR showed the highest performance,achieving stable CH3 OH yield of 117±28μmol/g in 5 consecutive cycles,these values are among the highest for Cu loaded MOR zeolites in open publications. | Chuang Ma Xianjun Tan Haijiao Zhang Qun Shen Nannan Sun Wei Wei | 2020 | Chinese Chemical Letters2020，31，1： | 2 |
| 5 | Laboratory investigations on the mechanical properties degradation of granite under freeze–thaw cycles显示文摘 | Xianjun Tan Weizhong Chen Jianping Yang Junjie Cao | 2011 | Cold Regions Science and Technology2011，，3： | 2 |
| 6 | Lateral compression and energy absorption of foamed concrete-filled polyethylene circular pipe as yielding layer for high geo-stress soft rock tunnels显示文摘Foamed concrete as energy absorption material for high geo-stress soft rock tunnels has been proven to be feasible due to its high compressibility and lightweight.However,the lengthy curing and defoaming problems caused by the cast-in-place method of large-volume foamed concrete remain unsolved.In this study,we propose a novel energy absorber composed of foamed concrete-filled polyethylene(FC-PE)pipe and analyze its deformation and energy absorption capacity via quasi-static lateral compression experiments.Results show that FC-PE pipes exhibit typical three-stage deformation characteristics,comprising the elastic stage,the plastic plateau,and the densification stage.Furthermore,the plateau stress,energy absorption,and specific energy absorption of the specimens are 0.81–1.91 MPa,164–533 J,and 1.4–3.6 J/g,respectively.As the density of the foamed concrete increases,the plateau stress and energy absorption increase significantly.Conversely,the length of the plastic plateau and energy absorption efficiency decrease.Moreover,based on the vertical slice method,progressive compression of core material,and the 6 plastic hinges deformation mechanism of the pipe wall,a theoretical calculation method for effective energy absorption is established and achieves good agreement with experimental results,which is beneficial to the optimization of the composite structure. | Chaoxuan Zhang Xianjun Tan Hongming Tian Weizhong Chen | 2022 | International Journal of Mining Science and Technology2022，32，5： | 1 |
| 7 | Guidelines for the diagnosis and treatment of acute pancreatitis in China (2021)显示文摘Acute pancreatitis(AP)is a common acute abdominal condition of the digestive system.In recent years,treatment concepts,methods,and strategies for the diagnosis of AP have advanced,and this has played an important role in promoting the standardization of AP diagnosis and treatment and improving the treatment quality of AP patients.On the basis of previous guidelines and expert consensus,this guideline adopts an evidence-based,problem-based expression;synthesizes important clinical research data at home and abroad in the most recent 5 years;and forms 29 recommendations through multidisciplinary expert discussion,including diagnosis,treatment,and follow-up.It is expected to provide evidence support for the treatment of AP in the clinical setting in China. | Fei Li Shouwang Cai Feng Cao Rufu Chen Deliang Fu Chunlin Ge Chunyi Hao Jihui Hao Heguang Huang Zhixiang Jian Gang Jin Ang Li Haimin Li Shengping Li Weiqin Li Yixiong Li Tingbo Liang Xubao Liu Wenhui Lou Yi Miao Yiping Mou Chenghong Peng Renyi Qin Chenghao Shao Bei Sun Guang Tan Xiaodong Tian Huaizhi Wang Lei Wang Wei Wang Weilin Wang Junmin Wei Heshui Wu Wenming Wu Zheng Wu Changqing Yan Yinmo Yang Xiaoyu Yin Xianjun Yu Chunhui Yuan Taiping Zhang Yupei Zhao on behalf of the Chinese Pancreatic Surgery Association | 2021 | Journal of Pancreatology2021，4，2： | 1 |
| 8 | Reinventing MoS2 Co-catalytic Fenton reaction:Oxygen-incorporation mediating surface superoxide radical generation显示文摘To better understand the mechanisms of hydrogen peroxide(H_(2)O_(2))’s decomposition and reactive oxygen species(ROS)’s formation on the catalyst’s surface is always a critical issue for the environmental application of Fenton/Fenton-like reaction.We here report a new approach to activate H_(2)O_(2) in a co-catalytic Fenton system with oxygen incorporated MoS2,namely MoS_(2−x) O_(x) nanosheets.The MoS_(2−x) O_(x) nanosheets assisted co-catalytic Fenton system exhibited superior degradation activity of emerging antibiotic contaminants(e.g.,sulfamethoxazole).Combining density functional theory(DFT)calculation and experimental investigation,we demonstrated that oxygen incorporation could improve the intrinsic conductivity of MoS_(2−x) O_(x) nanosheets and accelerate surface/interfacial charge transfer,which further leads to the efficacious activation of H_(2)O_(2).Moreover,by tuning the oxygen proportion in MoS_(2−x) O_(x) nanosheets,we are able to modulate the generation of ROS and further direct the oriented-conversion of H_(2)O_(2) to surface-bounded superoxide radical(·O_(2−surface)).It sheds light on the generation and transformation of ROS in the engineered system(e.g.,Fenton,Fenton-like reaction)for efficient degradation of persistent pollutants. | Xianjun Tan Wenhui Ding Zhenying Jiang Linxiao Sun Yuxiong Huang | 2022 | Nano Research2022，15，3： | 1 |
| 9 | Effects of thawing-induced softening on fracture behaviors of frozen rock显示文摘Due to the presence of ice and unfrozen water in pores of frozen rock,the rock fracture behaviors are susceptible to temperature.In this study,the potential thawing-induced softening effects on the fracture behaviors of frozen rock is evaluated by testing the tension fracture toughness(KIC)of frozen rock at different temperatures(i.e.-20℃,-15℃,-12℃,-10℃,-8℃,-6℃,-4℃,-2℃,and 0℃).Acoustic emission(AE)and digital image correlation(DIC)methods are utilized to analyze the microcrack propagation during fracturing.The melting of pore ice is measured using nuclear magnetic resonance(NMR)method.The results indicate that:(1)The KIC of frozen rock decreases moderately between-20℃ and-4℃,and rapidly between-4℃ and 0℃.(2)At-20℃ to-4℃,the fracturing process,deduced from the DIC results at the notch tip,exhibits three stages:elastic deformation,microcrack propagation and microcrack coalescence.However,at-4℃e0℃,only the latter two stages are observed.(3)At-4℃e0℃,the AE activities during fracturing are less than that at-20℃ to-4℃,while more small events are reported.(4)The NMR results demonstrate a reverse variation trend in pore ice content with increasing temperature,that is,a moderate decrease is followed by a sharp decrease and-4℃ is exactly the critical temperature.Next,we interpret the thawing-induced softening effect by linking the evolution in microscopic structure of frozen rock with its macroscopic fracture behaviors as follow:from-20℃ to-4℃,the thickening of the unfrozen water film diminishes the cementation strength between ice and rock skeleton,leading to the decrease in fracture parameters.From-4℃ to 0℃,the cementation effect of ice almost vanishes,and the filling effect of pore ice is reduced significantly,which facilitates microcrack propagation and thus the easier fracture of frozen rocks. | Ting Wang Hailiang Jia Qiang Sun Xianjun Tan Liyun Tang | 2024 | Journal of Rock Mechanics and Geotechnical Engineering2024，16，3： | 0 |
| 10 | A model of unfrozen water content in rock during freezing and thawing with experimental validation by nuclear magnetic resonance显示文摘The unfrozen water content of rock during freezing and thawing has an important influence on its physical and mechanical properties.This study presented a model for calculating the unfrozen water content of rock during freezing and thawing process,considering the influence of unfrozen water film and rock pore structure,which can reflect the hysteresis and super-cooling effects.The pore size distribution cu rves of red sandsto ne and its unfrozen water conte nt under different temperatures during the freezing and thawing process were measured using nuclear magnetic resonance(NMR) to validate the proposed model.Comparison between the experimental and calculated results indicated that the theoretical model accu rately reflected the water content change law of red sandstone during the freezing and thawing process.Furthermore,the influences of Hamaker constant and surface relaxation parameter on the model results were examined.The results showed that the appropriate magnitude order of Hamaker constant for the red sandstone was 10J to 10J;and when the relaxation parameter of the rock surface was within 25-30 μm/ms,the calculated unfrozen water content using the proposed model was consistent with the experimental value. | Zhouzhou Su Xianjun Tan Weizhong Chen Hailiang Jia Fei Xu | 2022 | Journal of Rock Mechanics and Geotechnical Engineering2022，14，5： | 0 |
| 11 | Consensus of clinical diagnosis and treatment for non-functional pancreatic neuroendocrine neoplasms with diameter<2 cm显示文摘In clinical practice,pancreatic neuroendocrine neoplasms(pNENs)with a diameter smaller than 2 cm are commonly referred to as small pNENs.Due to their generally favorable biological characteristics,the diagnosis and treatment of small pNENs differ from other pNENs and are somewhat controversial.In response to this,the Chinese Pancreatic Surgery Association,Chinese Society of Surgery,Chinese Medical Association have developed a consensus on the diagnosis and treatment of small pNENs,which is based on evidence-based medicine and expert opinions.This consensus covers various topics,including concepts,disease assessment,treatment selection,follow-up,and other relevant aspects. | Wu Wenming Cai Shouwang Chen Rufu Fu Deliang Ge Chunlin Hao Chunyi Hao Jihui Huang Heguang Jian Zhixiang Jin Gang Li Fei Li Haimin Li Shengping Li Weiqin LiYixiong Liang Tingbo Liu Xubao Lou Wenhui Miao Yi Mou Yiping Peng Chenghong Qin Renyi Shao Chenghao Sun Bei Tan Guang Wang Huaizhi Wang Lei Wang Wei Wang Weilin Wei Junmin Wu Heshui Wu Zheng Yan Changqing Yang Yinmo Yin Xiaoyu Yu Xianjun Yuan Chunhui Zhao Yupei | 2023 | Journal of Pancreatology2023，6，3： | 0 |
| 12 | Photo-induced surface frustrated Lewis pairs for promoted photocatalytic decomposition of perfluorooctanoic acid显示文摘Heterogeneous photocatalysis has gained substantial research interest in treating per-and polyfluoroalkyl substances(PFAS)-contaminated water.However,sluggish degradation kinetics and low defluorination efficiency compromise their practical applications.Here,we report a superior photocatalyst,defected Bi_(3)O(OH)(PO_(4))_(2),which could effectively degrade typical PFAS,perfluorooctanoic acid(PFOA),with high defluorination efficiency.The UV light irradiation could in situ generate oxygen vacancies on Bi_(3)O(OH)(PO_(4))_(2) through oxidation of the lattice hydroxyls,which further promotes the formation of Lewis acidic coordinately unsaturated bismuth sites.Then,the Lewis acidic sites couple with the proximal surface hydroxyls to constitute the surface frustrated Lewis pairs(SFLPs).With the in-depth spectroscopic analysis,we revealed that the photo-induced SFLPs act as collection centers to effectively adsorb PFOA and endow accessible pathways to transfer photogenerated holes to PFOA rapidly.Consequently,activation of the terminal carboxyl,a ratelimiting step for PFOA decomposition,could be easily achieved over the defected Bi_(3)O(OH)(PO_(4))_(2) photocatalyst.These results suggest that SFLPs exhibit great potential in developing highly efficient photocatalysts to degrade persistent organic pollutants. | Xianjun Tan Zhenying Jiang Yuxiong Huang | 2023 | Frontiers of Environmental Science & Engineering2023，17，1： | 0 |
| 13 | Guidelines for the diagnosis and treatment of pancreatic cancer in China (2021)显示文摘The incidence of pancreatic cancer has been rising worldwide,and its clinical diagnosis and treatment remain a great challenge.To present the update and improvements in the clinical diagnosis and treatment of pancreatic cancer in recent years,Chinese Pancreatic Association,the Chinese Society of Surgery,Chinese Medical Association revised the Guidelines for the Diagnosis and Treatment of Pancreatic Cancer in China(2014)after reviewing evidence-based and problem-oriented literature published during 2015-2021,mainly focusing on highlight issues regarding diagnosis and surgical treatment of pancreatic cancer,conversion strategies for locally advanced pancreatic cancer,treatment of pancreatic cancer with oligo metastasis,adjuvant and neoadjuvant therapy,standardized processing of surgical specimens and evaluation of surgical margin status,systemic treatment for unresectable pancreatic cancer,genetic testing,as well as postoperative follow up of patients with pancreatic cancer.Forty recommendation items were finally proposed based on the above issues,and the quality of evidence and strength of recommendations were graded using the Grades of Recommendation,Assessment,Development,and Evaluation system.This guideline aims to standardize the clinical diagnosis and therapy,especially surgical treatment of pancreatic cancer in China,and further improve the prognosis of patients with pancreatic cancer. | Yinmo Yang Xueli Bai Dapeng Bian Shouwang Cai Rufu Chen Feng Cao Menghua Dai Chihua Fang Deliang Fu Chunlin Ge Xiaochao Guo Chunyi Hao Jihui Hao Heguang Huang Zhixiang Jian Gang Jin Fei Li Haimin Li Shengping Li Weiqin Li Yixiong Li Hongzhen Li Tingbo Liang Xubao Liu Wenhui Lou Yi Miao Yiping Mou Chenghong Peng Renyi Qin Chenghao Shao Bei Sun Guang Tan Xiaodong Tian Huaizhi Wang Lei Wang Wei Wang Weilin Wang Junmin Wei Heshui Wu Wenming Wu Zheng Wu Jingyong Xu Changqing Yan Xiaoyu Yin Xianjun Yu Chunhui Yuan Taiping Zhang Jixin Zhang Jun Zhou Yupei Zhao on behalf of the Chinese Pancreatic Surgery Association | 2021 | Journal of Pancreatology2021，4，2： | 0 |
| 14 | Displacement-based back analysis of mitigating the effects of displacement loss in underground engineering显示文摘Displacement-monitoring-based back analysis is a popular method for geomechanical parameter estimation.However,due to the delayed installation of multi-point extensometers,the monitoring curve is only a part of the overall one,leading to displacement loss.Besides,the monitoring and construction time on the monitoring curve is difficult to determine.In the literature,the final displacement was selected for the back analysis,which could induce unreliable results.In this paper,a displacement-based back analysis method to mitigate the influence of displacement loss is developed.A robust hybrid optimization algorithm is proposed as a substitute for time-consuming numerical simulation.It integrates the strengths of the nonlinear mapping and prediction capability of the support vector machine(SVM)algorithm,the global searching and optimization characteristics of the optimized particle swarm optimization(OPSO)algorithm,and the nonlinear numerical simulation capability of ABAQUS.To avoid being trapped in the local optimum and to improve the efficiency of optimization,the standard PSO algorithm is improved and is compared with other three algorithms(genetic algorithm(GA),simulated annealing(SA),and standard PSO).The results indicate the superiority of OPSO algorithm.Finally,the hybrid optimization algorithm is applied to an engineering project.The back-analyzed parameters are submitted to numerical analysis,and comparison between the calculated and monitoring displacement curve shows that this hybrid algorithm can offer a reasonable reference for geomechanical parameters estimation. | Hui Li Weizhong Chen Xianjun Tan | 2023 | Journal of Rock Mechanics and Geotechnical Engineering2023，15，10： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员