311   Mechanical behaviour of heavily deformed CuAgZr conductor materials Mechanical behaviour of heavily deformed CuAgZr conductor materials    2010 The mechanical properties of Cu-7m.%Ag-0.05m.%Zr-alloys have been improved by optimised thermo-mechanical treatments. After processing the conductor material shows an ultimate tensile strength of more than 1.1 GPa, a yield strength of about 1 GPa, a plastic strain of 0.7%, and a conductivity of 60 %IACS (at room temperature). The yield strength of a cold deformed Cu - 7m.%Ag - 0.05m.%Zr-alloy has been assessed on the basis of different hardening mechanisms: solid solution, grain boundary, precip... 查看全文

312   Modelling of 7050 aluminium alloy friction stir welding Modelling of 7050 aluminium alloy friction stir welding    2009 A thermal model combined with a microstructural and yield strength model has been developed to give a prediction of precipitate evolution and strength in the as welded and post-weld heat treated condition for friction stir welding of 7xxx aerospace aluminium alloys. This fully coupled model is applied to an overaged high strength 7050 aluminium alloy friction stir welded using a range of welding rotation and translation speeds. The evolution of the microstructure has been predicted as a function... 查看全文

313   Acylation of Amino Acids with Furancarboxylic Acid Chlorides Acylation of Amino Acids with Furancarboxylic Acid Chlorides I. M. Lapina;L. M. Pevzner    2001 Acylation of aromatic amino acids with furancarboxylic acid chlorides effectively proceeds in water-acetone medium at pH 8-9. Aliphatic amino acids are acylated at higher pH values, but under these conditions hydrolysis of acid chlorides becomes the main process. Acylation of chlorohydrates of methyl esters of aliphatic amino acids proceeds smoothly in chloroform. in the presence of triethylamine. Alkaline hydrolysis of obtained products leads to N-acylated amino acids containing furan heterorin... 查看全文

314   Noname manuscript. No. (will be inserted by the editor) A 3-Slope Theorem for the Infinite Relaxation in the Plane Noname manuscript. No. (will be inserted by the editor) A 3-Slope Theorem for the Infinite Relaxation in the Plane Gérard Cornuéjols, Marco Molinaro    0 the date of receipt and acceptance should be inserted later Abstract In this paper we consider the infinite relaxation of the corner polyhedron with 2 rows. For the 1-row case, Gomory and Johnson proved in their seminal paper a sufficient condition for a minimal function to be extreme, the celebrated 2-Slope Theorem. Despite increased interest in understanding the multiple row setting, no generalization of this theorem was known for this case. We present an extension of the 2-Slope Theorem for t... 查看全文

315   to Class of '94 to Class of '94 Katherine Shim    0 The mean standardized test scores of 2011 students admitted to the Class of 1994 were comparable to those of last year, according to Associate Director of Admissions Elizabeth H. Johnson. The admissions reflect changes that were instituted last year in the system used to rate applicants. The changes resulted in significantly higher test scores in the Class of 1993 compared with those of previous years. The average math score on the Scholastic Aptitude Test was 739, while the average score in ver... 查看全文

316   The effect of test machine compliance on the measured shear punch yield stress as predicted using finite element analysis The effect of test machine compliance on the measured shear punch yield stress as predicted using finite element analysis    2002 In previous research involving the use of shear punch test, it was understood that some compliance was present in the test frame. and fixturing for a shear punch test, but it was assumed that this compliance would only affect the slope of the loading curve and not the perceived yield point on a shear punch test trace. The present work explores this assumption and its ramifications by simulating the shear punch test with finite element analysis (FEA). The simulations suggest that punch tip displa... 查看全文

317   CODS: Evolving Data Efficiently and Scalably in Column Oriented Databases CODS: Evolving Data Efficiently and Scalably in Column Oriented Databases Ziyang Liu, Sivaramakrishnan Natarajan, Bin He, Yi Chen    0 Database evolution is the process of updating the schema of a database or data warehouse (schema evolution) and evolving the data to the updated schema (data evolution). Database evolution is often necessitated in relational databases due to the changes of data or workload, the suboptimal initial schema design, or the availability of new knowledge of the database. It involves two steps: updating the database schema, and evolving the data to the new schema. Despite the capability of commercial RD... 查看全文

318   Stannous fluoride in dentifrice: an effective anti-plaque agent in the elderly? Stannous fluoride in dentifrice: an effective anti-plaque agent in the elderly? Ross C. Purdy    2007 Objective: The aim of this study was to examine differences in plaque accumulation in elderly patients using two toothpastes, with either 0.2% sodium fluoride (NaF) or 0.4% stannous fluoride (SnF2), but otherwise identical. 查看全文

319   Graph Homomorphisms and Long Range Graph Homomorphisms and Long Range Graham R. Brightwell, Houghton St, Peter Winkler    2001 We show that if a graph H is k-colorable, then (k?1)-branching walks on H exhibit long range action, in the sense that the position of a token at time 0 constrains the configuration of its descendents arbitrarily far into the future. This long range action property is one of several investigated herein; all are similar in some respects to chromatic number but based on viewing H as the range, instead of the domain, of a graph homomorphism. The properties are based on combinatorial forms of probab... 查看全文

320   Ternary polymer blends: Prediction of mechanical properties for various phase structures Ternary polymer blends: Prediction of mechanical properties for various phase structures    2000 A predictive scheme is proposed for the simultaneous calculation of the modulus and yield (or tensile) strength of ternary polymer systems. According to the continuity or discontinuity of constituting phases, the scheme combines in two steps the models for binary systems: (i) in the interval of phase duality (co-continuity), a two-parameter equivalent box model is used along with the data on the phase continuity rendered by modified equations of the percolation theory; and (ii) the effects of a ... 查看全文

321   Calcium glycerophosphate and caries: a review of the literature Calcium glycerophosphate and caries: a review of the literature Ross C. Purdy    2010 Aim: To review studies in the dental literature regarding the anti-caries mode of action of glycerophosphate with special reference to calcium glycerophosphate. The cariostatic properties of calcium glycerophosphate have been demonstrated during numerous in vivo and in vitro studies. Several mechanisms have been suggested and these include plaque-pH buffering, elevation of plaque calcium and phosphate levels and direct interaction with dental mineral. There is credible evidence that calcium glyc... 查看全文

322   An approach to modeling climate based on feedback relationships An approach to modeling climate based on feedback relationships Peter B. Wright    1979 Feedback occurs between many components of the climate system, and makes the study of climate very difficult. A modeling approach is presented in which feedbacks are represented specifically. Analysis of very simple models shows how feedback between two components affects their behavior; positive feedback increases persistence, and can produce climatic changes even without changes in external forcing. In any quantitative study, the magnitudes of all relevant feedbacks must be known accurately. A... 查看全文

323   Non-destructive pulsed field CuAg-solenoids Non-destructive pulsed field CuAg-solenoids    2010 Ultra strong CuAg-based conductor materials have been developed and tested in pulsed high-field magnets. The yield strength of a cold deformed CuAgZr conductor material has been assessed on the basis of different hardening mechanisms: solid solution, grain boundary, precipitation and dislocation hardening. The experimental value for the yield strength when transferred to the shear strength by Schmid's law is between a linear and a quadratic superposition of the individual critical shear stresses... 查看全文

324   Implementation and Evaluation of the Mechanisms for Low Latency Communication on DIMMnet-2 Implementation and Evaluation of the Mechanisms for Low Latency Communication on DIMMnet-2 Yasuo Miyabe, Akira Kitamura, Yoshihiro Hamada, Tomotaka Miyasiro, Tetsu Izawa, Noboru Tanabe, Hiron    0 DIMMnet-2 is a network interface for PC cluster, plugged into a DIMM slot. Connecting network interface into commonly used memory bus reduces the cost of building PC cluster compared with using expensive machines with recent high performance I/O bus like PCIX. Moreover, low latency communication from the host CPU can be achieved. In this paper, implementation of the mechanisms for low latency communication on the DIMMnet-2 prototype board by making the best use of the mem... 查看全文

325   A Study of the Acid–Base Properties of Melts in the Na2O–B2O3–SiO2 System: II. Composition Joins with Sodium Oxide Contents of 25, 30, and 35 mol % A Study of the Acid–Base Properties of Melts in the Na2O–B2O3–SiO2 System: II. Composition Joins with Sodium Oxide Contents of 25, 30, and 35 mol % V. G. Konakov    2002 The exponent of oxygen ion activity pO = - logao 2 - - \log a_o ^{2 - } for melts in the Na2O–B2O3–SiO2 system along the composition joins with constant sodium oxide contents of 25, 30, and 35 mol % is studied by an electromotive force (emf) technique at 950°C. Measurements are performed using two variants of the technique of determining pO, namely, in high-temperature salt solutions of oxide systems in KF and with a salt bridge between two oxide melts. It is shown that the b... 查看全文

326   Experimental study of shear strength for high-strength concrete beams with high-strength stirrups Experimental study of shear strength for high-strength concrete beams with high-strength stirrups    2011 This paper presents an experimental study of shear behavior. of simply supported HSC beams reinforced with high-strength stirrups under monotonic concentrated loading. Six specimens with 150×300 mm square cross section were tested. The effects of three variables such as the stirrup ratio, stirrup yield strength and average confining stress are studied. Based on test results, the shear behavior. of HSC beams with high-strength stirrups was evaluated. Combined with other test results, shear ... 查看全文

327   Recruitment of a Clinical Field Trial Population: Reasons for Nonparticipation Recruitment of a Clinical Field Trial Population: Reasons for Nonparticipation    2007 查看全文

328   Backward-Euler stress update algorithm for the original Cam-clay model with the vertex singularity Backward-Euler stress update algorithm for the original Cam-clay model with the vertex singularity    2009 The original Cam-clay model (1963) is the earliest critical state soil model which can characterize stress, strain and strength of soils under the unified framework of plasticity theory. However the surface of this model in stress space is considered non-smooth. The vertex causes the discontinuity on the yield surface and is viewed as a drawback of the model. The aim of this research is to formulate a backward-Euler stress update algorithm with consideration to the vertex singularity for the ori... 查看全文

329   On macrohardness testing of Al-7 wt.% Si-Mg alloys II. An evaluation of models for hardness-yield strength relationships On macrohardness testing of Al-7 wt.% Si-Mg alloys II. An evaluation of models for hardness-yield strength relationships    2003 Past efforts to predict hardness-yield strength (YS) relationships in aluminum alloys have been reviewed. Hardness data for Al-7 wt.% Si-Mg alloys with three different Mg levels and artificially aged for different durations have been analyzed for possible hardness-yield strength relationships. All models reported in the literature, except for the one developed by Shabel and Young, have been found to be affected by alloy temper. A new model that is unaffected by alloy temper has been developed th... 查看全文

330   Predicting of torsional strength of RC beams by using different artificial neural network algorithms and building codes Predicting of torsional strength of RC beams by using different artificial neural network algorithms and building codes    2010 In this study, the efficiency of different artificial neural networks (ANNs) in predicting the torsional strength of reinforced concrete (RC) beams is firstly explored. Experimental data of 76 rectangular RC beams from an existing database in the literature were used to develop ANN model. The input parameters affecting the torsional strength were selected as cross-sectional area of beams, dimensions of closed stirrups, spacing of stirrups, cross-sectional area of one-leg of closed stirrup, yield... 查看全文

331   Social Evolution in Ants, by Andrew F.G. Bourke and Social Evolution in Ants, by Andrew F.G. Bourke and Edited John, R. Krebs, Thomas D. Seeley, Foraging Theory, David W. Stephens, R. Krebs, Jerram L. Bro    0 查看全文

332   Social science perspectives on the Social science perspectives on the Amltal Etzlonl    0 WHERE DO WE go from here and how? Granted that we are amidst a true crisis of legitimation and meaning, and not just going through the growing pains of a segment of our youth, what comes after upheaval? Will America decline and fall, as the Roman empire did supposedly after it lost its moral fiber? Is the United States of America ready to be retired, a nation whose sun ha5 set, like the British, Dutch and Belgians after their empires collapsed? Will the country fall apart as the Austro-Hungarian 查看全文

333   Prediction of failure strain and burst pressure in high yield-to-tensile strength ratio linepipe Prediction of failure strain and burst pressure in high yield-to-tensile strength ratio linepipe    2007 Failure pressures and strains were predicted for a number of burst tests as part of a project to explore failure strain in high yield-to-tensile strength ratio linepipe. Twenty-three methods for predicting the burst pressure and six methods of predicting the failure strain are compared with test results. Several methods were identified which gave accurate and reliable estimates of burst pressure. No method of accurately predicting the failure strain was found, though the best was noted. Crown Co... 查看全文

334   Comments on slope stability based on a series of Drucker-Prager failure criteria Comments on slope stability based on a series of Drucker-Prager failure criteria    2009 Different equivalent area Drucker-Prager yield criteria on π plane, such as DP4(meaning projection areas of Drucker-Prager and Mohr-Coulomb yield criteria being equal on π plane), DP5(meaning projection areas of Drucker-Prager and Matsuoka-Nakai yield criteria being equal on π plane) and DP6(meaning projection areas of Drucker-Prager and Lade-Duncan yield criteria being equal on π plane) yield criteria, can give a approximately estimation for soil failure strength under plane strain ... 查看全文

335   Effects of aluminum (III) and fluoride on the demineralization of bovine enamel: a longitudinal microradiographic study Effects of aluminum (III) and fluoride on the demineralization of bovine enamel: a longitudinal microradiographic study Gregory A. Mooney, A. T. Nogueria and David C. Cope    2007 Longitudinal microradiography has been used to determine inhibiting effects of aluminum (III), Al, and fluoride on mineral loss from slices of bovine enamel exposed to a demineralizing solution 4 h daily for 35 days. Inhibitor treatment was 5 min four times daily. For the remaining time, the samples were immersed in a neutral calcium phosphate solution which allowed neither remineralization nor demineralization. This study indicates that a 1-mM (27 ppm) solution of Al in a 0.1-M lactate solution... 查看全文

336   Simulation of microstructure evolution and yield strength of Al-Cu-Mg-Ag alloys before peak aging stage Simulation of microstructure evolution and yield strength of Al-Cu-Mg-Ag alloys before peak aging stage    2010 A prediction model for microstructure evolution and ageing strengthening was developed for Al-Cu-Mg-Ag alloys with high Cu/Mg ratio before peak ageing stage. Firstly, the expression of critical parameters was built for the quantitative relationship of Mg and Mg-Ag atom clusters to consumed Cu atoms during ω phase precipitation, i.e. the interface energy model of ω precipitates and the substrate. Provided the alloy is pseudo-binary approximation, quantitative distribution model of Cu ... 查看全文

337   Influence of microalloying elements (Nb, V, Ti) on yield strength in bainitic steels Influence of microalloying elements (Nb, V, Ti) on yield strength in bainitic steels    2008 In order to study the influence of microalloying elements in bainitic high strength steels, seven steels with different contents of V, Ti, Nb and N were investigated. The steel 35 CrMo 4 (C=0.38; Mn=0.82; Si= 0.25; Cr=0.83; Mo=O. 17, all in wt.%) was used as reference steel. CCT diagrams were determined by dilatometric tests at different cooling rates, and the maximum and minimum cooling rates for bainite formation were determined. With regard to tensile tests, the presence of precipitates in th... 查看全文

338   Estimation of in-situ concrete flexural strength using maturity Estimation of in-situ concrete flexural strength using maturity    2005 Concrete maturity is being recognized as a viable test method to measure in-situ strengths of early age concrete and to assist agencies in making informed decisions on construction schedules. This increased interest is partly due to improved data collection technology in recent years coupled with a better understanding of the effects of construction and curing temperature on early age and long term performance of rigid pavements. The "maturity index", which is correlated to strength gain in a co... 查看全文

339   Analysis of Tensile Strength Test Methodologies for Evaluating Oil and Gas Well Cement Systems Analysis of Tensile Strength Test Methodologies for Evaluating Oil and Gas Well Cement Systems    2003 Efforts to produce better annular isolation for oil and gas wells resulted in the development of methods to quantify the induced stresses that may occur within the cement sheath of a well. Along with the ability to calculate induced stresses in a cemented annulus, is the realization that typically, if there are sufficiently induced stresses to cause a mechanical failure of the set cement, failure will likely be of a tensile nature. While the ability to predict the compressive and the tensile str... 查看全文

340   Dentists, Drugs, and Decisions: Introduction to Part I-Therapeutic Drugs Dentists, Drugs, and Decisions: Introduction to Part I-Therapeutic Drugs LJ Walsh    2007 Numerous dental therapeutic agents or drugs are available over the counter or with prescription for patient use at home or in a professional office. Knowledge of the processes by which these agents are evaluated for safety and efficacy by the FDA and ADA is necessary for dental professionals to make intelligent decisions concerning their use. Several examples of problems with drug/cosmetic evaluations are cited. 查看全文

[1]  [2]  [3]  [4]  [5]  [6]  [7]  [8]  [9]  [10]  [11]  [12]  [13]  [14]  [15]  [16]  [17]  [18]  [19]  [20]  [21]  [22]  [23]  [24]  [25]  [26]  [27]  [28]  [29]  [30]  [31]  32  [33]  [34]  [35]  [36]  [37]  [38]  [39]  [40]  [41]  [42]  [43]  [44]  [45]  [46]  [47]  [48]  [49]  [50]  [51]  [52]  [53]  [54]  [55]  [56]  [57]  [58]  [59]  [60]  [61]  [62]  [63]  [64]  [65]  [66]  [67]  [68]  [69]  [70]  [71]  [72]  [73]  [74]  [75]  [76]  [77]  [78]  [79]  [80]  [81]  [82]  [83]  [84]  [85]  [86]  [87]  [88]  [89]  [90]  [91]  [92]  [93]  [94]  [95]  [96]  [97]  [98]  [99]  [100]  [101]  [102]  [103]  [104]  [105]  [106]  [107]  [108]  [109]  [110]  [111]  [112]  [113]  [114]  [115]  [116]  [117]  [118]  [119]  [120]  [121]  [122]  [123]  [124]  [125]  [126]  [127]  [128]  [129]  [130]  [131]  [132]  [133]  [134]  [135]  [136]  [137]  [138]  [139]  [140]  [141]  [142]  [143]  [144]  [145]  [146]  [147]  [148]  [149]  [150]  [151]  [152]  [153]  [154]  [155]  [156]  [157]  [158]  [159]  [160]  [161]  [162]  [163]  [164]  [165]  [166]  [167]  [168]  [169]  [170]  [171]  [172]  [173]  [174]  [175]  [176]  [177]  [178]  [179]  [180]  [181]  [182]  [183]  [184]  [185]  [186]  [187]  [188]  [189]  [190]  [191]  [192]  [193]  [194]  [195]  [196]  [197]  [198]  [199]  [200]  [201]  [202]  [203]  [204]  [205]  [206]  [207]  [208]  [209]  [210]  [211]  [212]  [213]  [214]  [215]  [216]  [217]  [218]  [219]  [220]  [221]  [222]  [223]  [224]  [225]  [226]  [227]  [228]  [229]  [230]  [231]  [232]  [233]  [234]  [235]  [236]  [237]  [238]  [239]  [240]  [241]  [242]  [243]  [244]  [245]  [246]  [247]  [248]  [249]  [250]  [251]  [252]  [253]  [254]  [255]  [256]  [257]  [258]  [259]  [260]  [261]  [262]  [263]  [264]  [265]  [266]  [267]  [268]  [269]  [270]  [271]  [272]  [273]  [274]  [275]  [276]  [277]  [278]  [279]  [280]  [281]  [282]  [283]  [284]  [285]  [286]  [287]  [288]  [289]  [290]  [291]  [292]  [293]  [294]  [295]  [296]  [297]  [298]  [299]  [300]  [301]  [302]  [303]  [304]  [305]  [306]  [307]  [308]  [309]  [310]  [311]  [312]  [313]  [314]  [315]  [316]  [317]  [318]  [319]  [320]  [321]  [322]  [323]  [324]  [325]  [326]  [327]  [328]  [329]  [330]  [331]  [332]  [333]  [334]  [335]  [336]  [337]  [338]  [339]  [340]  [341]  [342]  [343]  [344]  [345]  [346]  [347]  [348]  [349]  [350]  [351]  [352]  [353]  [354]  [355]  [356]  [357]  [358]  [359]  [360]  [361]  [362]  [363]  [364]  [365]  [366]  [367]  [368]  [369]  [370]  [371]  [372]  [373]  [374]  [375]  [376]  [377]  [378]  [379]  [380]  [381]  [382]  [383]  [384]  [385]  [386]  [387]  [388]  [389]  [390]  [391]  [392]  [393]  [394]  [395]  [396]  [397]  [398]  [399]  [400]  [401]  [402]  [403]  [404]  [405]  [406]  [407]  [408]  [409]  [410]  [411]  [412]  [413]  [414]  [415]  [416]  [417]  [418]  [419]  [420]  [421]  [422]  [423]  [424]  [425]  [426]  [427]  [428]  [429]  [430]  [431]  [432]  [433]  [434]  [435]  [436]  [437]  [438]  [439]  [440]  [441]  [442]  [443]  [444]  [445]  [446]  [447]  [448]  [449]  [450]  [451]  [452]  [453]  [454]  [455]  [456]  [457]  [458]  [459]  [460]  [461]  [462]  [463]  [464]  [465]  [466]  [467]  [468]  [469]  [470]  [471]  [472]  [473]  [474]  [475]  [476]  [477]  [478]  [479]  [480]  [481]  [482]  [483]  [484]  [485]  [486]  [487]  [488]  [489]  [490]  [491]  [492]  [493]  [494]  [495]  [496]  [497]  [498]  [499]  [500]   下一页