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Chinese Journal of Polymer Science 2014年第12期32卷 1690-1703页

作者： J.h.Trivedi M.d.Thaker h.C.Trivedi P.G. department of Chemistry Sardar Patel University

Photo-induced graft copolymerization of methyl methacrylate（MMA） onto sodium salt of partially carboxymethylated guar gum（Na-PCMGG, dS = 0.291） was carried out in an aqueous medium using ceric ammonium nitrate（CAN） as photoinitiator to synthesize a novel graft copolymer, Na-PCMGG-g-PMMA, which may find its potential application as a metal adsorbent. The influences of synthesis variables such as concentrations of photoinitiator（CAN）, nitric acid and monomer（MMA） as well as reaction time, temperature and amount of substrate on the grafting yields were studied and the reaction conditions for optimum photo-grafting were evaluated. At optimum concentration, the maximum values of the grafting yields achieved were G = 271.61% and GE = 63.89%. The experimental results were found to be in very good agreement with the proposed kinetic scheme. The photo-graft copolymerization of MMA onto Na-PCMGG（ dS = 0.291） was also carried out in the presence and absence of ultraviolet radiation for studying the efficiency of the photoinitiator. The influence of carboxymethyl groups introduced onto the guar gum molecules with regard to its behavior towards ultra-violet radiation induced grafting with MMA was also investigated. Photo-grafting process was confirmed and the products were characterized with the help of the spectroscopic（1h-NMR and FTir） and SEM techniques.

关键词： Photo-induced grafting Methyl methacrylate Sodium salt of partially carboxymethylated guar gum Optimum reaction conditions Characterization.

Formulation and procedure for in situ stress back-analysis from borehole strain changes measured during nearby underground excavation

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第8期15卷 1931-1943页

作者： Cui Lin d.h.Steve Zou Mineral Resource Engineering Dalhousie UniversityHalifaxCanada

Estimation of in situ stresses based on back-analysis of measured stress changes and displacements has become an alternative to the direct stress measurement *** order to help users conduct own measurement and analysis,this paper presents in detail a field stress back-analysis approach directly from borehole strain changes measured during nearby underground *** formulations in major steps and the procedure for the entire analysis process are provided to allow users to *** instrument for borehole strain change measurement can be the CSir or CSirO stress cells and other borehole strain cells that can measure strains on borehole *** changes corresponding to the stress changes at a borehole location are calculated in borehole *** stress changes due to nearby excavation can be calculated by an analytical model for a single circular opening and simulated by a numerical model for non-circular and multiple *** models are based on isotropic,homogeneous and linear elastic *** analysis of borehole strain changes is accomplished by multiple linear regression based on error minimization and an integrated process provides the best-fit solution directly to the in situ stresses.A statistical technique is adopted for screening outliers in the measurement data,checking measurement compatibility and evaluating the reliability of analysis *** application example is included to demonstrate the practical application and the analysis procedure.

关键词： In situ stress field Back-analysis Borehole strain change Multiple linear regression Underground excavation data compatibility Result reliability

Mechanical and thermal postbuckling of FGM thick circular cylindrical shells reinforced by FGM stiffener system using higher-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2017年第1期38卷 73-98页

作者： d.V.dUNG h.T.ThIEM Faculty of Mathematics Mechanics and InformaticsVietnam National UniversityHanoi 100000Vietnam

The postbuckling of the eccentrically stiffened circular cylindrical shells made of functionally graded materials （FGMs）, subjected to the axial compressive load and external uniform pressure and filled inside by the elastic foundations in the thermal environments, is investigated with an analytical method. The shells are reinforced by FGM stringers and rings. The thermal elements of the shells and stiffeners in the fundamental equations are considered. The equilibrium and nonlinear stability equations in terms of the displacement components for the stiffened shells are derived with the third-order shear deformation theory and Leckhniskii smeared stiffener technique. The closed-form expressions for determining the buckling load and postbuckling load-deflection curves are obtained with the Galerkin method. The effects of the stiffeners, the foundations, the material and dimensional parameters, and the pre-existent axial compressive and thermal load are considered.

关键词： stiffened cylindrical shell functionally graded material (FGM) postbuck- ling elastic foundation analytical

Modified Joint distribution of Wave heights and Periods

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China Ocean Engineering 2016年第3期30卷 359-374页

作者： h.d.Zhang C.Guedes Soares Centre for Marine Technology and Ocean Engineering (CENTEC) Instituto Superior Técnico Universidade de Lisboa

The modified versions of the linear theoretical model of Longuet-higgins （1983） are derived in this work and also compared with the laboratory experiments carried out in MAR1NTEK. The main feature of modifications is to replace the mean frequency in the formulation with the peak frequency of the wave spectrum. These two alternative forms of joint distributions are checked in three typical random sea states characterized by the initial wave steepness. In order to further explore the properties ＆these models, the associated marginal distributions of wave heights and wave periods are also researched with the observed statistics and some encouraging results are obtained.

关键词： Longuet-higgins joint distribution mixed sea state nonlinear wave series wave height wave period

Analytical investigation of Jeffery-hamel flow with high magnetic field and nanoparticle by Adomian decomposition method

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Applied Mathematics and Mechanics(English Edition) 2012年第1期33卷 25-36页

作者： M.ShEIKhOLESLAMI d.d.GANJI h.R.AShORYNEJAd h.B.ROKNI Faculty of Mechanical Engineering Babol University of TechnologyP.O.Box 484BabolIslamic Republic of Iran

In this study, the effects of magnetic field and nanoparticle on the Jeffery- hamel flow are studied using a powerful analytical method called the Adomian decomposition method （AdM）. The traditional Navier-Stokes equation of fluid mechanics and Maxwell＇s electromagnetism governing equations are reduced to nonlinear ordinary differential equations to model the problem. The obtained results are well agreed with that of the Runge-Kutta method. The present plots confirm that the method has high accuracy for different a, ha, and Re numbers. The flow field inside the divergent channel is studied for various values of hartmann ：number and angle of channel. The effect of nanoparticle volume fraction in the absence of magnetic field is investigated.

关键词： magnetohydrodynamic Jeffery-hamel flow Adomian decomposition method nonlinear ordinary differential equation nanofluid

decoupling coefficients of dilatational wave for Biot's dynamic equation and its Green's functions in frequency domain

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Applied Mathematics and Mechanics(English Edition) 2016年第1期37卷 121-136页

作者： Boyang dING A.h.d.ChENG Zhanglong ChEN City College Zhejiang University department of Civil Engineering Zhejiang University of Technology College of Civil Engineering and Architecture University of Mississippi

Green＇s functions for Blot＇s dynamic equation in the frequency domain can be a highly useful tool for the investigation of dynamic responses of a saturated porous medium. Its applications are found in soil dynamics, seismology, earthquake engineering, rock mechanics, geophysics, and acoustics. however, the mathematical work for deriving it can be daunting. Green＇s functions have been presented utilizing an analogy between the dynamic thermoelasticity and the dynamic poroelasticity in the frequency domain using the u-p formulation. In this work, a special term ＂decoupling coefficient＂ for the decomposition of the fast and slow dilatational waves is proposed and expressed to present a new methodology for deriving the poroelastodynamic Green＇s functions. The correct- ness of the solution is demonstrated by numerically comparing the current solution with Cheng＇s previous solution. The separation of the two waves in the present methodology allows the more accurate evaluation of Green＇s functions, particularly the solution of the slow dilatational wave. This can be advantageous for the numerical implementation of the boundary element method （BEM） and other applications.

关键词： decoupling coefficient dilatational wave Biot's equation poroelastodynamic Green's function frequency domain

Evaluation of effects of 1,3-dinitrobenzene on sperm motility of hamster using computer assisted semen analysis (CASA)

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Asian Journal of Andrology 2001年第2期3卷 109-114页

作者： L.d.C.Peiris h.d.M.Moore dept. of Zoology University of Colombo Colombo 03 Sri LankaDept. of Molecular Biology and Biotechnology University of Sheffield Sheffield S 10 2TN UK

Aim: To evaluate the effects of 1,3-dinitrobenznene (mdNB) on sperm motility of hamster and to correlate the re-sults with the fertility. Methods: Adult male hamsters were gavaged with one of the 3 dose regimes of mdNB(1.5 mg daily for 4 weeks ,1.5 mg one day a week for 4 weeks and 1.0 mg 3 days a week for 4 weeks). Computerassisted semen analysis (CASA) was used to analyse the sperm motility parameters, curvilinear velocity (VCL) andstraight line velocity (VSL) of sperm in distal corpus epididymides and distal cauda epididymides. In vitro fertilisationwas carried out only for 1.5 mg mdNB daily group to determine the sperm fertilising capacity. Results: There wasa significant reduction in sperm velocity parameters at weeks 3 and 4 after treatment, which was correlated with a de-cline in sperm fertility. Conclusion; Sperm velocity parameters may be used to determine the effect of a toxic insulton the sperm function.

关键词： mdNB sperm motility CASA sperm fertility

Effects of acut and chronic doses of methoxy acetic acid on hamster sperm fertilising ability

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Asian Journal of Andrology 2001年第3期3卷 209-216页

作者： L.d.C.Peiris h.d.M.Moore dept. of Zoology University of Colombo Colombo 03 Sri LankaDept. of Molecular Biology and Biotechnology University of Sheffield Sheffield S10 2TN UK

Aim: To evaluate the effects of acute and chronic doses of methoxy acetic acid (MAA) on in vitro fertilisation byhamster sperm and to correlate the data with the testicular damage. Methods: Adult male hamsters were gavagedwith 3 single doses (0, 80, 160 and 650 mg/kg) and 3 chronic doses (0, 8, 32 and 64 mg/kg daily for 5 weeks) ofMAA in distilled water. After treatment hamsters were killed at weekly intervals and spermatozoa recovered from thedistal cauda epididymides were used to assess the fertilising capacity in vitro. The testes were processed for histologicalexamination. Results; Acute doses showed a significant reduction in sperm fertilising ability from week 3 and 4 af-ter treatment and with the chronic doses, the effects were more extensive and persistent. The results were in correpon-dence with the testicular damages observed. Conclusion: It is evident that both acute and chronic doses of MAAcan impair the sperm function by damaging one or more cell populations in the testis.(Asian J Androl 2001 Sep; 3: 209- 216)

关键词： methoxy acetic acid fertilisation in vitro testis spermatozoa fertility

Achieving excellent strength-ductility synergy in twinned NiCoCr medium-entropy alloy via Al/Ta co-doping

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Journal of Materials Science & Technology 2021年第28期87卷 184-195页

作者： d.d.Zhang h.Wang J.Y.Zhang h.Xue G.Liu J.Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049PR China Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu610041PR China

Alloying is an effective strategy to tailor microstructure and mechanical properties of metallic materials to overcome the strength-ductility trade-off *** this work,we combined a novel alloy design principle,*** pronounced solid solution hardening(SSh)based on the misfit volumes engineering,and simultaneously,architecting the ductile matrix based on the valence electron concentrations(VEC)criterion,to fulfill an excellent strength-ductility synergy for the newly emerging high/medium-entropy alloys(hEAs/MEAs).Based on this strategy,Al/Ta co-doping within NiCoCr MEA leads to an efficient synthetic approach,that is minor Al/Ta co-doping not only renders significantly enhanced strength with notable SSh effect and ultrahigh strain-hardening capability,but also sharply refines grains and induces abnormal twinning behaviors of(NiCoCr)_(92)Al_(6)Ta_(2) *** with the partially twinned NiCoCr MEA,the yield strength(σy)and ultimate tensile strength(σUTS)of fully twinned Al/Ta-containing MEA were increased by~102%to~600 MPa and~35%to~1000 MPa,respectively,along with good ductility beyond 50%.different from the NiCoCr MEA with deformation twins(dTs)/stacking faults(SFs)dominated plasticity,the extraordinary strain-hardening capability of the solute-hardened(NiCoCr)_(92)Al_(6)Ta_(2) MEA,deactivated deformation twinning,originates from the high density of dislocation walls,microbands and abundance of *** abnormal twinning behaviors,i.e.,prevalence of annealing twins(ATs)but absence of dTs in(NiCoCr)_(92)Al_(6)Ta_(2) MEA,are explained in terms of the relaxation of grain boundaries(for ATs)and the twinning mechanism transition(for dTs),respectively.

关键词： Medium-entropy alloys Mechanical properties Solid solution hardening Twinning behavior Strength-ductility synergy

EFFECT OF CARBON ANd BORON ON MICROSTRUCTURE ANd MEChANICAL PROPERTIES OF A SINGLE CRYSTAL SUPERALLOY RR 2072

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Acta Metallurgica Sinica(English Letters) 2005年第1期18卷 33-38页

作者： d.h.Kim d.h.Ye J.h.Lee Y.S.Yoo C.Y.Jo high Temperature Materials Laboratory Korea Institute of Machinery&Materials 66 SangnamChangwonKyungnam 640-010S.Korea dept.of Metallurgy Changwon National Univerisity 9 SarimChagwonKyungnam 640-773S.Korea

Carbon and boron have been considered to strengthen grain boundaries that might form during single crystal *** this study the effect of boron on solidification behavior and creep properties of the carbon doped single crystal RR 2072 has been *** order to understand solidification behavior with boron addition,the solid/liquid interface morphology and solidification microstructure were examined with solidification *** relationship between mi-crostructural evolution and creep properties of the carbon and boron modified single crystal has been also investigated.

关键词： single crystal superalloy defect tolerance directional solidification creep rupture