331   Fluoride Poisoning and Cholinesterases in Rats. Fluoride Poisoning and Cholinesterases in Rats. Kenji NOZAKA    2009 查看全文

332   Simulation methods for life and remaining strength prediction of high-temperature polymeric composites subjected to cyclic loads Simulation methods for life and remaining strength prediction of high-temperature polymeric composites subjected to cyclic loads    1997 The purpose of this paper is to establish and demonstrate a methodology for the prediction of the remaining strength and life of polymer-based composite laminates subjected to cyclic and sustained thermomechanical conditions. Conditions to be considered include elevated temperature (in air) and cyclic (fatigue) loading at various stress levels. The approach taken is to construct a simulation of the damage accumulation process and failure mode that controls the remaining strength and life for car... 查看全文

333   A model for the yield strength of overaged Al-Zn-Mg-Cu alloys A model for the yield strength of overaged Al-Zn-Mg-Cu alloys    2003 A model for the yield strength of multi-component alloys is presented and applied to overaged Al-Zn-Mg-Cu alloys (7xxx series). The model is based on an approximation of the strengthening due to precipitate bypassing during precipitate coarsening and takes account of ternary and higher order systems. It takes account of the influence of supersaturation on precipitation rates and of volume fraction on coarsening rates, as well crystallographic texture and recrystallisation. The model has been suc... 查看全文

334   Prediction of the effect of artificial aging heat treatment on the yield strength of an open-cell aluminum foam Prediction of the effect of artificial aging heat treatment on the yield strength of an open-cell aluminum foam    2008 The effect of artificial aging on the compression yield strength of an open-cell AA6101 foam is studied using both experimental and modeling approaches. Isothermal calorimetry is used to analyze the precipitation kinetics of the foam. The modeling work combines the established approaches for predicting the yield strength of open-cell metallic foams as a function of the relative density and normalized strength, as well as the age hardening behavior. of AA6101 alloy. The foam yield strength is rel... 查看全文

335   Characteristics of stress distribution and prediction of strength in heat affected zone softened welded joints Characteristics of stress distribution and prediction of strength in heat affected zone softened welded joints    2004 The effects of yield stress decrease due to coarsening grain in the HAZ (heat affected zone) of fine-grain steel welded joints on the load capacity of joint are required to be evaluated. The finite element analysis is carried out on tensile plate specimen of butt-welded joint with softened HAZ. The stress distribution in such joints shows that the Mises equivalent stress increases with the exponential law in the welds and base metal adjacent to softened HAZ, and that in softened HAZ decreases co... 查看全文

336   Operational Aspects of a County-Wide Self-Administered Fluoride Program Operational Aspects of a County-Wide Self-Administered Fluoride Program    2009 查看全文

337   Disintegration of the Lecithin Lamellar Phase by Cationic Surfactants Disintegration of the Lecithin Lamellar Phase by Cationic Surfactants Jonas Gustafsson,*† Greger Orädd,‡ and Mats Almgren†    1997 The phase behavior. of egg lecithin mixed with two cationic surfactants, hexadecyl- and dodecyltrimethylammonium chloride (C16TAC and C12TAC, respectively), in brine (100 mM NaCl) has been studied. Combining results from NMR spectroscopy, small-angle X-ray diffraction, and cryo-transmission electron microscopy, the phase sequence in less solvent rich regions of the phase diagram is linked to the aggregate structures appearing in dilute samples. The focus is set on the lamellar phases and their r... 查看全文

338   Improving empirical relationships for predicting the effect of vegetation change on annual water yield Improving empirical relationships for predicting the effect of vegetation change on annual water yield    2006 Continuing worldwide growth in results from paired-catchment vegetation-change experiments raises the possibility of improving empirical predictions of change in annual water yield. However, the results are variable, and a large amount of variation in change in annual yield is not explained by relationships derived from the results. We investigated causes of this unexplained variation (scatter), for relationships between change in annual yield and precipitation, and proposed procedures for impro... 查看全文

339   Yield line analysis of cropped-web Warren truss joints Yield line analysis of cropped-web Warren truss joints    1988 The yield line analysis method is used to develop an expression for predicting yield strengths of joints in welded Warren-type hollow structural section trusses with round end-cropped webs and rectangular chords. Yield strengths computed using the expression are compared with those measured in an experimental investigation of 39 Warren-type cropped-web HSS truss joint specimens. Good agreement between the measured and predicted values is demonstrated. The yield strength expression is augmented, ... 查看全文

340   Iterative solvers in the Newton power flow problem: preconditioners, inexact solutions, and partial Jacobian updates Iterative solvers in the Newton power flow problem: preconditioners, inexact solutions, and partial Jacobian updates F. de León    0 A comparative study of available iterative solvers (for linear systems of equations) applied to the solution of the nonlinear Newton power flow problem is presented. Iterative solvers are combined with Newton's method and an optimal stopping strategy is included to obtain an efficient solution for large power systems. Using the solvers and preconditioners available in Matlab, it is shown that iterative solvers are more efficient than the direct LU solution for large power systems. An easy to imp... 查看全文

341   Combined effects of stress ratio and yield strength on the LEFM fatigue threshold condition Combined effects of stress ratio and yield strength on the LEFM fatigue threshold condition    1992 Long-crack (LEFM) fatigue threshold, ΔK0, values are predicted which include the commonly observed effects of stress ratio, R, and yield strength, σy. It is assumed that the yield strength effect on threshold is indirectly related to grain size and so is not an independent variable. Two intrinsic thresholds of a material are invoked to explain the observations of higher ΔK0 values and a higher R-ratio sensitivity of ΔK0 in low strength materials compared to high strength ... 查看全文

342   Biological activities of chamomile ( Matricaria chamomile ) flowers’ extract against the survival and egg laying of the cattle fever tick (Acari Ixodidae) Biological activities of chamomile ( Matricaria chamomile ) flowers’ extract against the survival and egg laying of the cattle fever tick (Acari Ixodidae) Khodadad Pirali-Kheirabadi;Mehdi Razzaghi-Abyaneh    2007 In the present work, the potential of acaricidal activity of chamomile flowers’ extract was studied against engorged Rhipicephalus annulatus tick under laboratory condition. For this purpose, the engorged females of Rhipicephalus annulatus were exposed to two-fold serial dilutions of chamomile flowers’ extract (0.5%, 1.0%, 2.0%, 4.0% and 8.0%) using “dipping method” in vitro. The engorged ticks were immersed in different plant dilutions (five ticks for each diluti... 查看全文

343   Mechanical behavior. of δ-phase Pu-Ga alloys. Part II: Model verification and application Mechanical behavior. of δ-phase Pu-Ga alloys. Part II: Model verification and application    2006 We validated the mechanical threshold strength (MTS) model, developed in Part I, with approximately 50 different experimental results from the literature for both yield strength and ultimate tensile strength on Pu-Ga alloys. One standard deviation of the differences between the model's yield-strength predictions and the experiments was 7.5% of the measured yield strength. The model also worked well predicting the ultimate tensile strength (UTS) of the alloys with gallium concentrations of 1 wt% ... 查看全文

344   Model for post-yield tension stiffening and rebar rupture in concrete members Model for post-yield tension stiffening and rebar rupture in concrete members    2011 A tension stiffening model is presented which enables the calculation of average tensile stresses in concrete, after yielding of reinforcement, in reinforced concrete elements subjected to uniaxial tension, shear or flexure. To determine the average tensile stress-strain relationship for concrete, a crack analysis approach is employed taking into account the bond mechanism between concrete and deformed reinforcing bars, and numerical analyses are conducted to determine the tensile behavior. of r... 查看全文

345   YIELD STRENGTH AND MICROSTRUCTURAL SCALE: A CONTINUUM STUDY OF PEARLITIC VERSUS SPHEROIDIZED STEEL. YIELD STRENGTH AND MICROSTRUCTURAL SCALE: A CONTINUUM STUDY OF PEARLITIC VERSUS SPHEROIDIZED STEEL.    1973 A continuum mechanics approach is applied to the microstructure of pearlitic and spheroidized steels and compared with experiment as in earlier studies of WC-Co and aluminum-silicon. Success in the prediction of the yield strengths of pearlitic steels from the yield strengths of spheroidized steels requires little more than the conventional starting points in metallurgy and mechanics. Major conclusions which emerge are the same for all these very different crystal and microstructures. The flow s... 查看全文

346   A NEW APPROACH TO PREVENTING DENTAL CARIES THROUGH THE SCHOOL HEALTH PROGRAM A NEW APPROACH TO PREVENTING DENTAL CARIES THROUGH THE SCHOOL HEALTH PROGRAM    2009 查看全文

347   Homogenization approach to the yield strength of composite materials Homogenization approach to the yield strength of composite materials    1991 Unlike most of the classical approaches which resort to phenomenological criteria for describing the ultimate behaviour of composite materials, the implementation of a homogenization procedure within the framework of the yield design theory makes it possible to construct such a criterion in a rigorous way. A general formulation of the macroscopic strength condition for fibre reinforced composite materials is thus derived from the sole knowledge of the strength properties of their constituents (m... 查看全文

348   Model for predicting phase transformation and yield strength of vanadium microalloyed carbon steels Model for predicting phase transformation and yield strength of vanadium microalloyed carbon steels    2012 An integrated model for predicting recrystallization, phase transformation and yield strength of vanadium- microalloyed carbon steel (V-steel) is developed. Two effects of vanadium addition on recrystallization are assumed: one is the solute-drag effect on mobility of grain boundary, the other is pinning-effect on austenite grain growth due to vanadium carbide (VC) precipitate in austenite. The austenite grain size is considered as the control variable for nucleation density in grain corner, gra... 查看全文

349   High-temperature yield strength and its dependence on primary creep and recovery High-temperature yield strength and its dependence on primary creep and recovery    2011 Elasto-Delayed-Elastic-Viscous (EDEV), a predictive material model for 'quasi constant-structure' primary creep is used in developing an algorithm for predicting stress-strain diagrams at constant strain rates. The strain rate dependence of the 0.2% offset yield-strength (σy), time to yield, and the amounts of permanent (viscous) and the recoverable (anelastic or delayed elastic) strain components of the 0.2% offset strain can also be evaluated. Six material constants required for calculat... 查看全文

350   Lewis Acido-Basic Interactions between CO2 and MgO Surface: DFT and DRIFT Approaches Lewis Acido-Basic Interactions between CO2 and MgO Surface: DFT and DRIFT Approaches Damien Cornu†, Hazar Guesmi*†‡, Jean-Marc Krafft†‡, and Hélène Lauron-Pernot†    2012 Combined experimental infrared (IR) and theoretical approaches have been carried out in an attempt to specify the actual structure of the CO2 species adsorbed on the magnesium oxide surface. The interaction of CO2 with regular sites of the MgO(100), (111), and (110) surfaces as well as MgO(100) defect sites (steps, corners, kinks, and divacancies) has been investigated by means of density functional theory study. Theoretical IR frequencies compared with IR experiments show distinguishable carbon... 查看全文

351   Localization of Dras1 gene in polytene chromosomes of sibling species of Drosophila virilis group Localization of Dras1 gene in polytene chromosomes of sibling species of Drosophila virilis group V. G. Mitrofanov, A. I. Chekunova, E. S. Zelentsova, L. N. Gauze;G. N. Bakhtoyarov    2011 The Dras1 gene was mapped by in situ hybridization to polytene chromosomes of several sibling species of the Drosophila virilis group and their hybrids. A 1037-bp fragment of Dras1 gene from the D. virilis genome was used as the probe. The gene sequence was localized in the region of a 25 A-B disk in chromosome 2 (in accordance with the D. virilis polytene chromosome map (Gubenko and Evgen’ev, 1984). 查看全文

352   The Properties of Methylene- and Amine-Substituted Zeolites from First Principles The Properties of Methylene- and Amine-Substituted Zeolites from First Principles Roope Astala and Scott M. Auerbach*    2004 All-silica zeolite frameworks doped with methylene and amine groups are studied using density functional theory-based electron structure calculations. Strain energies are calculated in a novel way, by comparing zeolite energies with appropriate polymer reference systems. The modified zeolites are found to be mechanically stable structures with surprisingly little strain. Distortions due to impurities result in broadened Si?O?Si angle distributions in the lattice surrounding defects. Our results ... 查看全文

353   Improvement on CAE model for accurate torsional springback prediction in high strength steel part forming Improvement on CAE model for accurate torsional springback prediction in high strength steel part forming    2012 It is difficult to predict springback, torsion in particular, with great accuracy by FE simulation. In this study, the effects of anisotropic yield functions of the blank and elastic deformation of the tools on springback are investigated in order to improve the accuracy of torsional springback prediction in high strength steel part forming. The effects of anisotropic yield functions on the torsional springback in curved hat forming were compared, using parameter sets derived from various experi... 查看全文

354   In vitro acid decalcification of human surface enamel pretreated with toothpaste slurries In vitro acid decalcification of human surface enamel pretreated with toothpaste slurries J. Moran, M. Addy and R. Newcombe    2007 An in vitro caries-like challenge of human tooth enamel treated with inorganic fluoride (NaF) and organic fluoride (aliphatic and aromatic amine fluorides) toothpaste slurries has been investigated. The results revealed that the organic fluoridecontaining toothpastes affected positively the resistance of tooth enamel to demineralization. 查看全文

355   Use of miniature specimen test and finite element method for evaluation of yield strength and fracture toughness in metallic alloys Use of miniature specimen test and finite element method for evaluation of yield strength and fracture toughness in metallic alloys    2011 The present paper describes the method for evaluation of yield strength and fracture toughness of three materials, namely, linepipe steel, aluminum (Al) alloy, and gray cast iron using miniature specimen test. Conventional standard test methods consume more material and money and may damage the integrity of the in-service component. Miniature specimen tests overcome all these demerits.A method is outlined to predict the yield strength and fracture toughness from the miniature test through the em... 查看全文

356   Management of welding operations with high strength steels Management of welding operations with high strength steels    2009 High strength steels find ever increasing applications for several reasons: &bull Reducing the weight of structures, &bull Improving equipment performance, &bull Reducing costs (shipping, smaller lifting equipment, time required for welding operations ...) For steels with a yield strength up to 700 MPa, welding problems and issues are well known. However, welding operations are not always well conducted. For yield strength over 700 MPa, problems such as mismatch... are not fully predictabled. In... 查看全文

357   The Cariostatic Effectiveness of a Phosphate-Fluoride Gel Administered Annually to School Children I. The Results of the First Year The Cariostatic Effectiveness of a Phosphate-Fluoride Gel Administered Annually to School Children I. The Results of the First Year Geoffrey V. Stagg and David J. Millin    2007 Bryan and Williams report their experience with the application of phosphate-fluoride gel in foam-rubber trays. 查看全文

358   Acceleration in iterative imbased on the above performance, age restoration by manipulation of gain parameter Acceleration in iterative imbased on the above performance, age restoration by manipulation of gain parameter Ezzatollah Salari    0 One of the major disadvantages of the standard iterative image restoration is its linear rate of convergence. In this paper it is shown that for natural scenes and uniform. space invariant distortion, we can attain acceleration in the iteration process. It has been shown here that, for standard iterative restoration, if we choose the gain parameter close to but less than its upper limit and then after some iterations reduce it to exactly half of its upper limit, a close estimation of the origina... 查看全文

359   YIELD CRITERIA FOR PREDICTING THE STRENGTH OF METALS. YIELD CRITERIA FOR PREDICTING THE STRENGTH OF METALS.    1974 A new yield criterion is introduced. It is hyperbolic in form. so it is significantly different from the criteria developed by Rankine, Tresca, Saint-Venant, or von Mises. But like these criteria, the new yield condition is also limited to a biaxial stress condition. The new yield criterion, because of its form, serves as an instructive model for the development of an analytical equation of equivalent form. As a result, the new yield criterion can be interpreeted as an energy equation which incl... 查看全文

360   Asymmetric Organocatalytic Cascade Michael/Michael/Henry Reaction Sequence: Control of All Stereocenters in One Cyclohexane Skeleton Asymmetric Organocatalytic Cascade Michael/Michael/Henry Reaction Sequence: Control of All Stereocenters in One Cyclohexane Skeleton Benoit Schneider, Manuel Babolat, Ying Wu Xu, Joeuml;l Janin, Michel Veacute;ron and Dominique Devil    2012 The highly diastereo- and enantioselective relay cascade Michael/Michael/Henry reaction catalyzed by combination of readily available diphenylprolinol silyl ether and the quinine thiourea in a one-pot fashion has been developed. Up to 70% yield and up to >99% enantioselectivity of the single major isomer were obtained from the cascade reactions. 查看全文

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