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An efficient probabilistic design approach for tunnel face stability by inverse reliability analysis

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Geoscience Frontiers 2021年第5期12卷 374-383页

作者： jian ji Zheming Zhang Zhijun Wu jiacheng Xia Yongxin Wu Qing Lüc Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjingChina School of civil Engineering Wuhan UniversityWuhanChina c College of Civil EngineeringZhejiang UniversityHangzhouChina

In order to maintain the safety of underground constructions that significantly involve geo-material uncertainties,this paper delivers a new computation framework for conducting reliability-based design(RBD)of shallow tunnel face stability,utilizing a simplified inverse first-order reliability method(FORM).The limit state functions defining tunnel face stability are established for both collapse and blow-out modes of the tunnel face failure,respectively,and the deterministic results of the tunnel face support pressure are obtained through three-dimensional finite element limit analysis(FELA).Because the inverse reliability method can directly capture the design support pressure according to prescribed target reliability index,the computational cost for probabilistic design of tunnel face stability is greatly *** comparison with Monte carlo simulation results,the accuracy and feasibility of the proposed method are ***,this study presents a series of reliability-based design charts for vividly understanding the limit support pressure on tunnel face in both cohesionless(sandy)soil and cohesive soil stratums,and their optimal support pressure ranges are *** results show that in the case of sandy soil stratum,the blowout failure of tunnel face is extremely unlikely,whereas the collapse is the only possible failure *** parametric study of various geotechnical uncertainties also reveals that ignoring the potential correlation between soil shear strength parameters will lead to over-designed support pressure,and the coefficient of variation of internal friction angle has a greater influence on the tunnel face failure probability than that of the cohesion.

关键词： Tunnel face stability Support pressure Finite element limit analysis Inverse reliability analysis Probabilistic design

critical role of corrosion inhibitors modified by silyl ether functional groups on electrochemical performances of lithium manganese oxides

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Journal of Energy chemistry 2020年第12期29卷 425-433页

作者： Min ji Seong Taeeun Yim Department of chemistry Incheon National UniversityYeonsu-gu 22012IncheonRepublic of Korea Research Institute of Basic Sciences College of Natural ScienceIncheon National UniversityYeonsu-gu 22012IncheonRepublic of Korea

Lithium manganese oxides(Li Mn2 O4, LMO) have attracted significant attention as important cathode materials for lithium-ion batteries(LIBs), which require fast charging based on their intrinsic electrochemical properties. However, these properties are limited by the rapid fading of cycling retention, particularly at high temperatures, because of the severe Mn corrosion triggered by the chemical reaction with fluoride(F-) species existing in the cell. To alleviate this issue, three types of silyl ether(Si–O)-functionalized task-specific additives are proposed, namely methoxytrimethylsilane, dimethoxydimethylsilane, and trimethoxymethylsilane. Ex-situ NMR analyses demonstrated that the Si-additives selectively scavenged the F-species as Si forms new chemical bonds with F via a nucleophilic substitution reaction due to the high binding affinity of Si with F-, thereby leading to a decrease in the F concentration in the cell. Furthermore, the addition of Si-additives in the electrolyte did not significantly affect the ionic conductivity or electrochemical stability of the electrolyte, indicating that these additives are compatible with conventional electrolytes. In addition, the cells cycled with Si-additives exhibited improved cycling retention at room temperature and 45 °c. Among these candidates, a combination of MTSi and the LMO cathode was found to be the most suitable choice in terms of cycling retention(71.0%), whereas the cell cycled with the standard electrolyte suffered from the fading of cycling retention triggered by Mn dissolution(64.4%). Additional ex-situ analyses of the cycled electrodes using SEM, TEM, EIS, XPS, and IcP-MS demonstrated that the use of Si-additives not only improved the surface stability of the LMO cathode but also that of the graphite anode, as the Si-additives prevent Mn corrosion. This inhibits the formation of cracks on the surface of the LMO cathode, facilitating the formation of a stable solid electrolyte interphase layer on the su

关键词： Lithium-ion batteries Lithium manganese oxide cathode Electrolyte additive corrosion Silyl ether Fluoride scavenger

Modeling mass transfer of cO_2 in brine at high pressures by chemical potential gradient

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Science china chemistry 2013年第6期56卷 821-830页

作者： ji YuanHui ji XiaoYan LU XiaoHua TU YongMing Division of Energy Science Lule University of Technology State Key Laboratory of Materials-Oriented chemical Engineering Nanjing University of Technology Key Laboratory of concrete and Prestressed concrete Structures of Ministry of Education Southeast University Division of Structural Engineering and Bridges Royal Institute of Technology (KTH)

To investigate long-term cO2 behavior in geological formations and quantification of possible cO2 leaks, it is crucial to inves- tigate the potential mobility of cO2 dissolved in brines over a wide range of spatial and temporal scales and density distribu- tions in geological media. In this work, the mass transfer of aqueous cO2 in brines has been investigated by means of a chemi- cal potential gradient model based on non-equilibrium thermodynamics in which the statistical associating fluid theory equa- tion of state was used to calculate the fugacity coefficient of cO2 in brine. The investigation shows that the interracial concen- tration of aqueous cO2 and the corresponding density both increase with increasing pressure and decreasing temperature; the effective diffusion coefficients decrease initially and then increase with increasing pressure; and the density of the cO2-disolved brines increases with decreasing cO2 pressure in the cO2 dissolution process. The aqueous cO2 concentration profiles obtained by the chemical potential gradient model are considerably different from those obtained by the concentration gradient model, which shows the importance of considering non-ideality, especially when the pressure is high.

关键词： c02 geological sequestration dissolution non-equilibrium thermodynamics mass transport diffusion density SAFTEoS

Vortex Lines and Monopoles in Electrically conducting Plasmas

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communications in Theoretical Physics 2009年第2期51卷 335-340页

作者： WANG ji-Biao REN ji-Rong LI Ran Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

Based on the φ-mapping topological current theory and the decomposition of gauge potential theory, the vortex lines and the monopoles in electrically conducting plasmas are studied. It is pointed out that these two topological structures respectively inhere in two-dimensional and three-dimensional topological currents, which can be derived from the same topological term n^→·（Эin^→×Эjn^→）, and both these topological structures axe characterized by the φ-mapping topological numbers-Hopf indices and Brouwer degrees. Furthermore, the spatial bifurcation of vortex lines and the generation and annihilation of monopoles are also discussed. At last, we point out that the Hopf invaxiant is a proper topological invaxiant to describe the knotted solitons.

关键词： plasma vortex line monopole

complete convergence and complete Moment convergence for Maximal Weighted Sums of Extended Negatively Dependent Random Variables

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Acta Mathematica Sinica,English Series 2018年第10期34卷 1501-1516页

作者： ji Gao YAN School of Mathematical Sciences Soochow University c.A.S.E.-center for Applied Statistics and Economics Humboldt-Universitt zu Berlin

In this paper, the complete convergence and complete moment convergence for maximal weighted sums of extended negatively dependent random variables are investigated. Some sufficient conditions for the convergence are provided. In addition, the Marcinkiewicz Zygmund type strong law of large numbers for weighted sums of extended negatively dependent random variables is obtained. The results obtained in the article extend the corresponding ones for independent random variables and some dependent random variables.

关键词： Extended negatively dependent complete convergence complete moment convergence maximal weighted sums strong law of large numbers

The Innate Immune Response in Lateolabrax japonicus Induced by Lipopolysaccharide from Glaciecola polaris Strain ARK149(LMG21854)

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Agricultural Sciences in china 2010年第10期9卷 1504-1511页

作者： cHEN ji-gang college of Biological and Environmental Sciences Zhejiang Wanli University Ningbo 315100 P.R.China Municipal Key Laboratory of Microorganism and Environmental Engineering Ningbo 315100 P.R. China college of Fisheries Huazhong Agricultural University Wuhan 430070 P.R. China

Glaciecola polaris strain ARK149, a Gram-negative bacterium from Arctic seas, was used to derive lipopolysaccharide （LPS）, and the effect of the LPS inducing some innate immunity parameters was investigated in Japanese sea bass, Lateolabrax japonicus. The results showed that the LPS could enhance the phagocytosis activity, lysozyme activity, and bacteriolytic activity in ***, significantly （P〈0.05） at 1, 7, 14, 21, 28, and 35 d after LPS-injection. The indexes of three parameters increased to the peak of value at 28th d post LPS-injection. Moreover, RT-PcR analysis suggested that LPS significantly up-regulated the expression of both IL-8 and hepcidin in several tissues. These data suggest that the LPS extracted from Glaciecola polaris strain ARK149 can induce innate immunity in L. japonicus.

关键词： Lateolabraxjaponicus Glaciecola polaris lipopolysaccharide innate immunity RT-PcR

Bee Venom Acupuncture Induced Skin Patch Discoloration Persisting for More than 3 Years:A case Report

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chinese Journal of Integrative Medicine 2021年第10期27卷 774-777页

作者： ji Hye Hwang Department of Acupuncture&Moxibustion Medicine College of Korean MedicineGachon UniversitySeongnam(13120)Republic of Korea

Bee venom(BV),one of the most commonly encountered types of animal venom,consists of a mixture of chemical agents that cause allergic reactions in the human body.⑴BV therapy,in which BV is exploited for medicinal purposes,is available worldwide,mainly used in Asia,Eastern Europe,and South America.(2)BV therapy has been applied to treat a diverse set of diseases including various musculoskeletal conditions such as arthritis and rheumatism,arthralgia,chronic recalcitrant neuralgia,(3-5)Parkinson's disease,(6,7)postherpetic neuralgia,(8)and morphea.(9)Although the therapeutic utility of BV has been demonstrated,extensive studies regarding the safety of BV as a therapeutic agent have identified potential side effects,ranging from minor skin reactions that typically resolve over several days to severe life-threatening immune responses such as anaphylaxis.

关键词： Acupuncture diseases Bee

Biochemical characterization of an Arginine 2,3-Aminomutase with Dual Substrate Specificity

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chinese Journal of chemistry 2020年第9期38卷 959-962页

作者： Junfeng Zhao Wenjuan ji Xinjian ji Qi Zhang Department of chemistry Fudan University2005 Songhu RoadShanghai 200438China

Summary of main observation and conclusion The radical S-adenosylmethionine(SAM)aminomutases represent an important pathway for the biosynthesis of p-amino *** this study,we report biochemical characterization of BlsG involved in blasticidin S biosynthesis as a radical SAM arginine 2,*** showed that BlsG acts on both£-arginine and L-lysine with comparable catalytic *** dual substrate specificity was also observed for the lysine 2,3-aminomutase from Escherichia coli(LAMec).The catalytic efficiency of LAMEc is similar to that of BlsG,but is significantly lower than that of the enzyme from clostridium subterminale(LAMcs),which acts only on L-lysine rather than on ***,we showed that enzymes can be grouped into two major phylogenetic clades,each corresponding to a certain c3 stereochemistry of the P-amino acid *** study expands the radical SAM aminomutase members and provides insights into enzyme evolution,supporting a trade-off between substrate promiscuity and catalytic efficiency.

关键词： radical catalytic conclusion

A new interpretation for formation of orthogonal joints in quartz sandstone

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 289-299页

作者： Le Li Shaocheng ji Département des Génies civil Géologique et des MinesÉcole Polytechnique de MontréalMontréalQuébecH3C 3A7Canada

Two vertical and orthogonal systematic joint sets are generally arrayed in a grid pattern on the bedding surface,which are the significant features of flat-lying sandstone *** extensive researches are reported on this topic,many fundamental problems have still not been *** mutually perpendicular opening-mode fractures are an obvious manifestation of effective tensile stresses in two orthogonal directions in the horizontal bedding plane.A good understanding of these orthogonal joint systems is a key to structural analysis,landscape interpretation,and guidance of resolving a number of very practical problems in engineering,mining and hydrologic *** on an anatomic investigation on the orthogonal joints in the Potsdam sandstone of cambrian age at Ausable chasm(New York State,USA)and Beauharnois(Quebec,canada),we proposed that the orthogonal joints may result from the auxetic effects of quartz-rich sandstone rather than local or regional rotation of the maximum tensile stress(σ_(3))direction by about 90°.The sandstone beds with negative Poisson's ratios are so fascinating that,when placed under vertical burial compression and layer-parallel extension in one direction(σ_(3)),it becomes stretched in the transverse direction(σ_(2)),producing two orthogonal sets of mutual abutting and intersecting joints(J1 and J2 normal toσ_(3) andσ_(2),respectively),and both are normal to the bedding *** set J1 is more closely-spaced than J2 by a factor of∼3.3,which is correlated with an average Poisson's ratio of−0.3 for the Potsdam sandstone at the time of joint formation.

关键词： Rock fractures Orthogonal joints Sandstone Auxetic effects Potsdam group