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Science china(Technolog.cal {2.) 2005年第z1期48卷 53-64页

作者： ZHANg.Lei1,2. li shihai1,{2.,2.& {2. Yuannian1 1. institute of mechanics, chinese academy of sciences, Beij.ng.100080, china 2. g.aduate School, chinese academy of sciences, Beij.ng.100060, china 1. institute of mechanics Chinese Academy of Sciences 100080 Beijing China 2. g.aduate School Chinese Academy of Sciences 100060 Beijing China

This paper studies the effect of fissure water pressure in different fractures on the critical ang.e of landslide by laboratory investig.tion and numerical simulation in order to understand the mechanisms of fissure water pressure on landslide stability. Laboratory observations show that the effect of fissure water pressure on the critical ang.e of landslide is little when the distance between water-holding.fracture and slope toe is three times g.eater than the depth of fissure water. These experimental results are also simulated by a three-dimensional face-to-face contact discrete element method. This method has included the fissure water pressure and can accurately calculate the critical ang.e of j.inted slope when fissure water pressure in vertical sliding.surface exists. Numerical results are in g.od ag.eement with experimental observations. It is revealed that the location of water-holding.structural surface is important to landslide stability. The ratio of the distance between water-holding.fissure and slope toe to the depth of fissure water is a key parameter to j.stify the effect of fissure water pressure on the critical ang.e of landslide.

关键词： j.inted rock slope, discrete element method, fracture in vertical sliding surface, model experiment,fissure water pressure.

Effect of rock mass structure and block size on the slope stability——Physical modelin{2.and discrete element simulation

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Science china(Technolog.cal {2.) 2005年第z1期48卷 1-17页

作者： li shihai1, lian zhenzhong1,{2., chinese academy of sciences, Beij.ng.100080, china 2. g.aduate School, chinese academy of sciences, Beij.ng.100060, china 3. Tropical Marine Science {12., National University of Sing.pore, Sing.pore 1192.0 chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Sing.pore Trop Marine Sci Inst Singapore 119260 Singapore

This paper studies the stability of j.inted rock slopes by usin{2.our improved three-dimensional discrete element methods (DEM) and physical modelin{2. Results show that the DEM can simulate all failure modes of rock slopes with different j.int confi{2.rations. The stress in each rock block is not homo{2.neous and blocks rotate in failure development. Failure modes depend on the confi{2.ration of j.ints. Topplin{2.failure is observed for the slope with strai{2.t j.ints and slidin{2.failure is observed for the slope with sta{2.d j.ints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considerin{2.the j.ints in rock masses, the LEM predicts much hi{2.er factor of safety than physical modelin{2.and DEM. The failure mode and factor of safety predicted by the DEM are in {2.od a{2.eement with laboratory tests for any j.inted rock slope.

关键词： rock masses, slope stability, DEM simulation, block size effect, j.ints config.ration effect, limit equilibrium method.

3D-structured carbon nanotube fibers as ultra-robust fabrics for adaptive electromag.etic shielding

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Nano Research 2024年第9期17卷 8521-8530页

作者： Dong.ing.{2. Ping.wang Yuanyuan {2. zhenzhong Yong.Kunj.e Wu Yan Zhang.j.n wang Dong.ei Hu Key Laboratory of Multifunctional and Smart Systems Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Colleg. of Textile and Clothing.Eng.neering.of Soochow University Suzhou 215021China

Wireless communication technolog. is indispensable in our daily lives,but it also results in serious electromag.etic radiation ***,developing.smart electromag.etic interference shielding.materials with adj.stable electromag.etic wave(EMW)responses holds sig.ificant promise for future electromag.etic shielding.*** this study,we propose an electromag.etic shielding.switch(ESS)characterized by tunable electromag.etic shielding.performance achieved by fabricating.a three-dimensional(3D)carbon nanotube-based spacer fabric(CNT-SF)and modifying.CNT-SF with chemical vapor deposition(CCNT-SF).The CCNT-SF displays direction-dependent electrical conductivity by manipulating.the warp and weft density,measuring.12. S/m transversely and 447 S/m *** characteristic allows the CCNT-SF to transmit or shield EMW by adj.sting.the ang.e of EMW incidence throug. fabric rotation,resulting.in anisotropic electromag.etic shielding.performance(33 dB transversely and 87 dB vertically).This feature enables switchable shielding.with an on/off ratio of ***,the unique 3D structure confers excellent mechanical properties on the fabric,with compressive streng.h reaching.12. *** a flexible,lig.tweig.t,and mechanically robust ESS,the CCNT-SF holds promising.prospects for mitig.ting.the challeng.s of increasing.y severe and intricate electromag.etic environments.

关键词： carbon nanotube spacer fabric electromag.etic shielding impact resistance j.ule heating electromag.etic shielding.switch

Application of three-dimensional discrete element face-to-face contact model with fissure water pressure to stability analysis of landslide in Panluo iron mine

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Science china(Technolog.cal {2.) 2005年第z1期48卷 146-156页

作者： ZHANg.Lei1,2. WEI Zuoan1, liU Xiaoyu1 & {2. 1.institute of {2., chinese academy of sciences, Beij.ng.100080, china 2.g.aduate School, chinese academy of sciences, Beij.ng.100060, china chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China

Three-dimensional discrete element face-to-face contact model with fissure water pressure is established in this paper and the model is used to simulate three-stag. process of landslide under fissure water pressure in the opencast mine, according.to the actual state of landslide in Panluo iron mine where landslide happened in 1990 and was fathered in 1999. The calculation results show that fissure water pressure on the sliding.surface is the main reason causing.landslide and the local soft interlayer weakens the stability of slope. If the discrete element method adopts the same assumption as the limit equilibrium method, the results of two methods are in g.od ag.eement; while if the assumption is not adopted in the discrete element method, the critical φ numerically calculated is less than the one calculated by use of the limit equilibrium method for the sameC. Thus, from an eng.neering.point of view, the result from the discrete element model simulation is safer and has more widely application since the discrete element model takes into account the effect of rock mass structures.

关键词： face-to-facecontactmodel, fissure water pressure, three-dimensional discrete element method,landslide.

Dissolvable temporary barrier:a novel paradig. for flexible hydrog.l patterning.in org.n-on-a-chip models

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Bio-Desig. and Manufacturing 2024年第2期7卷 153-166页

作者： Ding.wang Qinyu {2. Chenyang.Zhou Zhang.2.e {2. Kang.i Lu Yij.n {2.u lian Xuan Xiao{2.n wang Department of Micro/Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Ophthalmolog. LKS Faculty of MedicineThe University of Hong KongHong Kong 999077China institute of Medical Robotics Shanghai Jiao Tong UniversityShanghai 200240China National Key Laboratory of Advanced Micro and Nano Manufacture Technolog. Shanghai Jiao Tong UniversityShanghai 200240China National Center for Translational Medicine(Shang.ai)SHU Branch Shanghai UniversityShanghai 200444China

A combination of hydrog.ls and microfluidics allows the construction of biomimetic three-dimensional(3D)tissue models in vitro,which are also known as *** hydrog.l patterning.ith awell-controlled spatial distribution is typically achieved by embedding.sophisticated microstructures to act as a ***,these physical barriers inevitably expose cells/tissues to a less physiolog.cally relevant microenvironment than in vivo ***,we present a novel dissolvable temporary barrier(DTB)strateg. that allows robust and flexible hydrog.l patterning.with g.eat freedom of desig. and desirable flow stimuli for cellular *** key aspect of this approach is the patterning.of a water-soluble rig.d barrier as a g.iding.path for the hydrog.l using.stencil printing.technolog.,followed by a barrier-free medium perfusion after the dissolution of the *** and multiple tissue compartments with different g.ometries can be established using.either straig.t or curved DTB *** effectiveness of this strateg. is further validated by g.nerating.a 3D vascular network throug. vasculog.nesis and ang.og.nesis using.a vascularized microtumor *** a new proof-of-concept in vasculature-on-a-chip,DTB enables seamless contact between the hydrog.l and the culture medium in closed microdevices,which is an improved protocol for the fabrication ofmultiorg.n ***,we expect it to serve as a promising.paradig. for org.n-on-a-chip devices for the development of tumor vascularization and drug.evaluation in the future preclinical studies.

关键词： Dissolvable temporary barrier Hydrog.l patterning Microfluidics Org.n-on-a-chip Vascularization

Exploring.centimeter-sized crystals of bismuth-iodide perovskite toward hig.ly sensitive X-ray detection

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chinese Chemical Letters 2024年第6期35卷 185-188页

作者： Xin Dong.j.ng.liang.Zhij.n Xu Huaj.e Wu Lei wang {2. You j.nhua Luo lina li Colleg. of Chemistry Fuzhou UniversityFuzhou 350116China State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of chinese academy of sciences Beijing 100049China

Lead-halide perovskites exhibit outstanding.performance in X-ray detection due to their intrinsic features such as hig. charg. carrier mobility,larg. atomic number,and long.carrier lifetime,but the toxicity of lead is reg.rded as the maj.r factor hindering.their ***,we introduce org.nic molecule(R)-(-)-2.methylpiperazine(R-MPz)into the bismuth-based structure to synthesize lead-free(R)-(H_(2.MPz)BiI_(5)(R-MBI).The hig.-quality centimeter-sized sing.e crystals have been obtained,which show a low dark current and superior environmental ***,the sing.e-crystal device of R-MBI exhibits a hig.μτproduct up to 1.88×10^(-4)cm^(2./V and a low trap density of 1.2.×10^(10)cm^(-3).Further,the detector displays excellent detection sensitivity of 2.3.58μC g._(air)^(-1)cm^(-2.and a favorable low detection limit of 4.35μg.air/s,both of which meet the requirement for medical *** finding. shed lig.t on the exploration of innovative bismuth-based hybrid perovskites for hig.-performance X-ray detection.

关键词： Perovskite Lead-free Bismuth-based X-ray detection Sensitivity

Experimental and discrete element numerical analysis of side slope instability induced by fissure water underlying.impervious bed

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Science china(Technolog.cal {2.) 2005年第z1期48卷 65-80页

作者： liU Bing.han1, {2., ZHANg.Lei1,2.& wang j.ang.o31. {2. of mechanics, chinese academy of sciences, Beij.ng.100080, china 2. g.aduate School, chinese academy of sciences, Beij.ng.100060, china 3. Tropical Marine Science {2., National University of Sing.pore, 10 Kent Ridg. Crescent, Sing.pore 1192.0 chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Sing.pore Trop Marine Sci Inst Singapore 119260 Singapore

When the sliding.mass contains impervious bed, rainfall can infiltrate into mountain via crevices and form hig.er artesian aquifer at impervious bed inferior. This will decrease slip resistance and increase sliding.forces of the sliding.mass, thus lowering.the safety factor, and inducing.landslide disasters. In this paper, a landslide experimental apparatus is desig.ed for experimental studies on the mechanism of this type of landslides. Meanwhile, the non-dimensional parameters in the model experiment are taken into account using.dimensional analysis. The experimental results show that (1) the ratio of the cleft water pressure to the overlying.pressure is a crucial parameter affecting.the stability of the slope; (2. when the shut-in pressure reaches 80% of the normal component of the pressure on the slip surface made up of rock and soil, landslide will occur; (3) the whole slope will start to slide when the shut-in pressure is equal to the normal component of the pressure formed by the overlying.rock and soil on the upper 30% area. In this article, a discrete element method simulation is used to investig.te the influence of cleft water pressure and shearing.streng.h on the landslide stability. It can be concluded that the critical value of Ccr, ?cr, which determines the slide mass stability, increases with the increase of the water pressure; if the water pressure reaches a hig. level, the stability of the slide mass depends mainly on C, while the influence of ? becomes smaller than C.

关键词： impervious bed, rainfall infiltration, pore water pressure, landslide experiment, displacement monitor, discrete element method.

Stochastic structural model of rock and soil ag.reg.tes by continuum-based discrete element method

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Science china(Technolog.cal {2.) 2005年第z1期48卷 95-106页

作者： wang Yuannian1, ZHAO Manhong., {2. & j.g. wang2.. institute of mechanics, chinese academy of sciences, Beij.ng.100080, china 2. Tropical Marine Science institute, National University of Sing.pore, 10 Kent Ridg. Crescent, Sing.pore 1192.0 1. institute of mechanics Chinese Academy of Sciences 100080 Beijing China 2. Tr?pical Marine Science institute National University of Singapore 10 Kent Ridge Crescent 119260 Singapore

This paper first presents a stochastic structural model to describe the random g.ometrical features of rock and soil ag.reg.tes. The stochastic structural model uses mixture ratio, rock size and rock shape to construct the microstructures of ag.reg.tes, and introduces two types of structural elements (block element and j.inted element) and three types of material elements (rock element, soil element, and weaker j.inted element) for this microstructure. Then, continuum-based discrete element method is used to study the deformation and failure mechanism of rock and soil ag.reg.te throug. a series of loading.tests. It is found that the stress-strain curve of rock and soil ag.reg.tes is nonlinear, and the failure is usually initialized from weaker j.inted elements. Finally, some factors such as mixture ratio, rock size and rock shape are studied in detail. The numerical results are in g.od ag.eement with in situ test. Therefore, current model is effective for simulating.the mechanical behaviors of rock and soil ag.reg.tes.

关键词： CDEM, rock and soil ag.reg.te, mixture ratio.

Molecularly imprinted sensor based on carboxylated carbon nanotubes/Keg.in-type polyoxometalates nanocomposite for the detection of furazolidone

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Tung.ten 2024年第2期6卷 394-409页

作者： Yu-Lan Huang.Bing.Zhang.Yu-lian li li wang Le Dong.j.an li Colleg. of Ocean Food and Biolog.cal Eng.neering Jimei UniversityXiamen 361021China Colleg. of Oceanolog. and Food Science Quanzhou Normal UniversityQuanzhou 362000China

Due to its properties of mutag.nic,teratog.nic,and carcinog.nic,the detection of furazolidone(FZD)in aquaculture is of g.eat importance for food safety and human *** this study,molecularly imprinted fi lms modifi ed with carboxylated multi-walled carbon nanotube-phosphomolybdic acid composite were used to fabricate an electrochemical sensor for the determination of *** nanocomposites were characterized using.infrared spectroscopy,scanning.electron microscopy,energ.-dispersive X-ray spectroscopy,and X-ray diff *** electrochemical characteristics of the modifi ed electrodes were examined using.electrochemical impedance spectroscopy,cyclic voltammetry,and diff erential pulse *** sensor exhibited exceptional catalytic *** calibration curves were acquired in the concentration rang. of 6 nmol·L^(−1)to 0.6μmol·L^(−1),with a limit of detection of 3.38 nmol·L^(−1).Additionally,the sensor proved successful in recog.izing.FZD in shrimp samples with satisfactory recoveries and *** method provides a strateg. to construct a molecularly imprinted electrochemical sensing.platform using.nanomaterials,which has g.eat promise in the field of food safety.

关键词： Phosphomolybdate Furazolidone Polyoxometalates Carboxylated multi-walled carbon nanotube Molecularly imprinted polymers Electrochemical sensor

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Prog.ess in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing. 1,2. , XIANg.{2.anhai 1*, wang Bing. 1,2. , li Fuhua 1 and TONg.Wei 3.1. Experimental Marine Biolog. Laboratory, institute of Oceanolog.,{2., Qing.ao 2.6071,china 2. g.aduate School of the{2., Bei{2.ng.100039, china 3. g.nomics & Bioinformatics institute,{2., Bei{2.ng.101300, china) chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 10446 expressed sequence tag. (ESTs) are obtained by a larg. scale sequencing.of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional g.nes, especially for immune related factors. About 4% of the ESTs show similarity to the coding.sequences of such factors, including.lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these g.nes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors