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Pedosphere 2005年第1期15卷 84-94页

作者： YANXiang-Kui K.w.ChANG h.L.XU NationalInstituteforAgro-EnvironmentalSciences Tsukuba-shi305-8506Japan／／GansuAgriculturalUniversityLanzhou730070China AgrochemistryDepartment ChungnamNationalUniversityKung-DongTaejon305-764Korea InternationalNatureFarmingResearchCenter 5632HataNagano390-1401（Japan）

A field experiment was conducted on a sandy loam soil at an Experimental Farm in Taejon, South Korea, to determine the effects of paper mill sludge compost application rates on K, Na, Ca and Mg concentrations of soybean (Glycine max (L.) Merr.) aboveground tissues and the genotypic effects on the concentrations of these elements. Sludge compost treatments of 0, 75, and 150 t ha-1 were applied to 30 diverse soybean cultivars. Concentrations of K, Na, Ca, and Mg in aboveground tissues harvested 69 days after …

关键词： calcium magnesium paper mill sludge potassium sodium soybean

wEAK-DUALITY BASED ADAPTIVE FINITE ELEMENT METhODS FOR PDE-CONSTRAINED OPTIMIZATION wITh POINTwISE GRADIENT STATE-CONSTRAINTS

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Journal of Computational Mathematics 2012年第2期30卷 101-123页

作者： M. hintermuer Michael hinze Ronald h.w. hoppe Department of Mathematics Humboldt-University of Berlin Germany Department of Mathematics University of Hamburg Germany Department of Mathematics University of Augsburg Germany and Department of MathematicsUniversity of Houston USA

Adaptive finite element methods for optimization problems for second order linear el- liptic partial differential equations subject to pointwise constraints on the l2-norm of the gradient of the state are considered. In a weak duality setting, i.e. without assuming a constraint qualification such as the existence of a Slater point, residual based a posteriori error estimators are derived. To overcome the lack in constraint qualification on the continuous level, the weak Fenchel dual is utilized. Several numerical tests illustrate the performance of the proposed error *** subject classification： 65N30, 90C46, 65N50, 49K20, 49N15, 65K10.

关键词： Adaptive finite element method A posteriori errors Dualization Low regu-larity Pointwise gradient constraints State constraints weak solutions.

Study and Application of Polarographic Catalytic wave of Chlordiazepoxide in the Presence of Persulfate

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Chinese Journal of Chemistry 2002年第5期20卷 502-508页

作者： Guo, w Lin, h Liu, LM Guo, ZA Song, JF Nw Univ Xian Dept Chem Xian 710069 Peoples R China Yuxi Normal Coll Dept Chem Yunnan 653100 Peoples R China

Polarographic catalytic wave of chlordiazepoxide in the presence of K 2S 2O 8 was studied in aqueous and DMF/h 2O mixed solutions. The results showed that a single reduction wave in alkaline medium was the reduction of the N=C bond in 1,2 position of chlordiazepoxide via an intermediate free radical in two one electron successive additions. when K 2S 2O 8 was present, the free radical of the N=C bond was oxidized to regenerate the original, producing a parallel catalytic wave of chlordiazepoxide. It was determined that the apparent rate constant k f of the oxidation reaction was 3.2×10 3 mol -1 ·L·s -1 . Using the catalytic wave the trace of chlordiazepoxide can be determined by linear potential scan polarography. In Nh 3/Nh 4Cl (ph 10.2±0.1, 0.12 mol/L)/K 2S 2O 8 (0.016 mol/L) supporting electrolyte, the second order derivative peak current of the catalytic wave was rectilinear to chlordiazepoxide concentration in the range of 3.20×10 -8 -1.60×10 -7 , 1.60×10 -7 -1.44×10 -6 and 1.44 ×10 -6 -1.44×10 -5 mol/L, respectively. The limit of detection was 9.0×10 -9 mol/L.

关键词： chlordiazepoxide persulfate polarographic catalytic wave free radical

Recent developments of surface complexation models applied to environmental aquatic chemistry

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Journal of Environmental Sciences 2001年第4期13卷 422-434页

作者： Liu, w.-X. Tang, h.-X. SKLEAC Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

Based on numerous latest references, the current developments in surface complexation, surface precipitation and the corresponding models (SCMs and SPMs), were reviewed. The contents involved comparison on surface charge composition and layer-structure of solid-solution interface for the classical 1-pK and 2-pK models. In addition, the fundamental concept and relations of the new models, i. e., multi-site complexation (MUSIC) and charge- distribution (CD) MUSIC models were described as well. To avoid misuse or abuse, it must be emphasized that the applicability and limitation for each model should be considered carefully when selecting the concerned model(s). In addition, some new powerful techniques for surface characterization and analysis applied to model establishment and modification were also briefly introduced.

关键词： Complexation Precipitation (chemical)

wAVE ATTENUATION OVER MUD BED: A PSEUDO-PLASTIC MODEL

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Journal of hydrodynamics 2003年第6期15卷 32-38页

作者： ZhangQing-he Onyxw.h.wai Josephh.w.Lee SchoolofCivilEngineering TianjinUniversityTianjin300072China DepartmentofCivilandStructuralEngineering TheHongKongPolytechnicUniversityHongKongChina DepartmentofCivilEngineering TheUniversityofHongKongHongKongChina

A two-layer model, with the upper layer being the perfect fluid and the lowerlayer being the pseudo-plastic fluid describing water wave attenuation over mud bed, wasestablished. A simplified method based on the principle of e-quivalcnt work was applied to solve theboundary value problems. The computational results of the model show that the two-layer perfectfluid model and the perfect-viscous fluid model are all special cases of the present model. Thecomplex nonlinear properties of wave attenuation over mud bed, can be explained by the presentmodel, e. g., the wave dissipation rale decreases wilh the wave height in certain cases, while thesmall wave propagates over mud bed with less energy dissipation and large wave attenuates rapidly inother cases. Other factors influencing the wave attenuation were also discussed.

关键词： wave attenuation mud bed pseudo-plastic model equivalent work

Sensitive analysis of amino acids in injection liquor by reversed-phase hPLC

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Chinese Journal of Chemistry 1995年第2期13卷 163-168页

作者： ShANG, Zh YU, YN GUO, w JIANG, h ZhOU, LM ChINESE ACAD SCI DALIAN INST CHEM PHYSDALIAN 116012PEOPLES R CHINA

A convenient derivatization method of amino acids with 1-fluoro-2,4-dinitrobezene as reaction reagent and a separation system were described. The derivative amino acids were separated on a specific chemically bonded phase column with a simple linear gradient elution consisting of aqueous buffer and methanol. The eluate was detected by common ultraviolet absorption detector at 360 nm. The detection limits of amino acids were as low as 10 picomole. This method has been successfully applied to assay amino acid injection liquor used in hospital. It has good reproducibility and precision. The procedures avoid the requirements of particular derivative equipment and analyzer employed in conventional amino acid analysis.

关键词： AMINO ACIDS PRECOLUMN DERIVATIZATION REVERSED PhASE SEPARATION UV ABSORPTION DETERMINATION

A Finite Element Method for Modelling Electromechanical wave Propagation in Anisotropic Piezoelectric Media

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Communications in Computational Physics 2007年第2期2卷 271-292页

作者： S.Rahman h.P.Langtangen C.h.w.Barnes Cavendish Laboratory Cambridge UniversityJ J Thomson AvenueCambridgeCB3 OHEUnited Kingdom Simula Research Laboratory Martin Linges v 17Fornebu P.O.Box 1341325 LysakerNorway

we describe and evaluate a numerical solution strategy for simulating surface acoustic waves(SAws)through semiconductor devices with complex *** multi-physics problem is of particular relevance to the design of SAw-based quantum electronic *** mathematical model consists of two coupled partial differential equations for the elastic wave propagation and the electric field,respectively,in anisotropic piezoelectric *** equations are discretized by the finite element method in space and by a finite difference method in *** latter method yields a convenient numerical decoupling of the governing *** describe how a computer implementation can utilize the decoupling and,via object-oriented programming techniques reuse independent codes for the Poisson equation and the linear time-dependent elasticity *** we apply the simulator to a simplified model problem for verifying the implementation,and thereafter we show that the methodology is capable of simulating a real-world case from nanotechnology,involving SAws in a geometrically non-trivial device made of Gallium ***:***,***,*** Key words:Finite element method,piezoelectric surface acoustic waves,Gallium Arsenide.

关键词： Finite element method piezoelectric surface acoustic waves Gallium Arsenide.

Laser additive manufacturing of biodegradable Mg-based alloys for biomedical applications: A review

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Journal of Magnesium and Alloys 2022年第4期10卷 915-937页

作者： C.L.wu w.J.Xie h.C.Man Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

Metallic implants are widely used in internal fixation of bone fracture in surgical *** are mainly used for providing mechanical support and stability during bone reunion,which usually takes a few months to *** implants made of stainless steels,Ti-based alloys and CoCrMo alloys have been widely used for orthopedic reconstruction due to their high strength and high corrosion *** metallic implants will remain permanently inside the body after implantation,and a second surgery after bone healing is needed because the long-term presence of implant will lead to various *** implant removal surgery not only incurs expenditure,but also risk and psychological *** a consequence,studies on the development of biodegradable implants,which would degrade and disappear in vivo after bone reunion is completed,have drawn researchers’*** this connection,Mg-based alloys have shown great potentials as promising implant materials mainly due to their low density,inherent biocompatibility,biodegradability and mechanical properties close to those of ***,the high degradation rate of Mg-based implants in vivo is the biggest hurdle to *** from materials selection,a fixation implant is ideally tailor-made in size and shape for an individual case,for best surgical ***,laser additive manufacturing(LAM),with the advent of sophisticated laser systems and software,is an ideal process to solve these *** this paper,we reviewed the progress in LAM of biodegradable Mg-based alloys for biomedical *** effect of powder properties and laser processing parameter on the formability and quality was thoroughly *** microstructure,phase constituents and metallurgical defects formed in the LAMed samples were *** mechanical properties,corrosion resistance,biocompatibility and antibacterial properties of the LAMed samples were summarized and compared with samples fabricated by

关键词： Laser additive manufacturing Magnesium alloys Implant Biomedical applications Mechanical properties Biodegradability

Electron Beam Curing of Advanced Composites

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Journal of Materials Science & Technology 2000年第6期16卷 627-630页

作者： Sui, G. Zhong, w.h. Zhang, Z.G. Dep. of Materials Sci. and Eng. Beijing Univ. of Aeron. and Astron. Beijing 100083 China

The fundamental concept of electron beam method and the application in cure of composites are elaborated in this paper. The components of electron beam curing system are introduced. The mechanisms of interaction between electron beam and polymer matrix composites are presented. Recent studies including work of authors themselves on electron beam curing of composites are also discussed. Moreover, the authors believe that it is necessary to do the basic research about understanding how electron beam affects cured network and the mechanical/physical properties of the composites for establishing a quantitative or semi-quantitative formulation.

关键词： Electron Beam Curing of Advanced Composites EB

Effect of longwall-induced subsurface deformations on shale gas well casing stability under deep covers

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International Journal of Mining Science and Technology 2019年第1期29卷 3-8页

作者： Daniel w.h.Su Peter Zhang Mark Van Dyke Todd Minoski Center for Disease Control and Prevention(CDC) National Institute for Occupational Safety and Health(NIOSH)Pittsburgh Mining Research Division(PMRD)

This paper presents the results of a 2017 study conducted by the National Institute for Occupational Safety and health(NIOSh), Pittsburgh Mining Research Division(PMRD), to evaluate the effects of longwall-induced subsurface deformations within a longwall abutment pillar under deep cover. The 2017 study was conducted in a southwestern Pennsylvania coal mine, which extracts 457 m-wide longwall panels under 361 m of cover. One 198 m-deep, in-place inclinometer monitoring well was drilled and installed over a 45 m by 84 m center abutment pillar. In addition to the monitoring well, surface subsidence measurements and underground coal pillar pressure measurements were conducted as the 457 m-wide longwall panel on the south side of the abutment pillar was being mined. Prior to the first longwall excavation, a number of simulations using FLAC3D^(TM) were conducted to estimate surface subsidence, increases in underground coal pillar pressure, and subsurface horizontal displacements in the monitoring well. Comparisons of the pre-mining FLAC3D simulation results and the surface, subsurface,and underground instrumentation results show that the measured in-place inclinometer casing deformations are in reasonable agreement with those predicted by the 3D finite difference models. The measured surface subsidence and pillar pressure are in excellent agreement with those predicted by the 3D *** from this 2017 research clearly indicate that, under deep cover, the measured horizontal displacements within the abutment pillar are approximately one order of magnitude smaller than those measured in a 2014 study under medium cover.

关键词： Longwall Deformations Shale gas wells Casing Safety and health