321   Long-term creep strength and strength reduction factor for welded joints of ASME grades 91, 92 and 122 type steels Long-term creep strength and strength reduction factor for welded joints of ASME grades 91, 92 and 122 type steels    2011 Creep rupture data of base metal and welded joints of several creep strength enhanced ferritic (CSEF) steels was collected and long-term creep strength of those steels was evaluated by the SHC committee in Japan. The previous allowable tensile stress of those steels regulated in METI Thermal Power Standard Code was reviewed and weld strength reduction factor was investigated. The master creep life equations for not only base metal, but also welded joints were developed. According to the evaluate... 查看全文

322   Dramatic Pressure Effects on the Selectivity of the Aqueous/Organic Biphasic Hydrogenation of trans-Cinnamaldehyde Catalyzed by Water-Soluble Ru(II)-Tertiary Phosphane Complexes Dramatic Pressure Effects on the Selectivity of the Aqueous/Organic Biphasic Hydrogenation of trans-Cinnamaldehyde Catalyzed by Water-Soluble Ru(II)-Tertiary Phosphane Complexes P. Beat Rheiner and Dieter Seebach    2003 In a water/chlorobenzene biphasic reaction, the hydrogenation of trans-cinnamaldehyde, catalyzed by water-soluble Ru(II)-phosphane complexes at pH 3.04 (phosphate buffer), produces a 61:39 mixture of cinnamyl alcohol and dihydrocinnamaldehyde at 1 bar H2; however, the selectivity is increased to 93:7 by increasing the hydrogen pressure to 8 bar. 查看全文

323   Texture/yield strength correlations in Al-Li near-net-shape extrusions Texture/yield strength correlations in Al-Li near-net-shape extrusions    2000 The objective of this investigation was to correlate textural characteristics with yield strength anisotropy in identical T-stiffened extruded panels manufactured from the Al-Li alloys 2195, RX818 and 2096. Two regions within the panels were examined; mid-way between the stiffeners (skin) and directly beneath the stiffeners (base). In all three extrusions, the texture in the skin region was comparable to rolled product and that in the base region similar to axisymmetric extruded product. The res... 查看全文

324   A method of predicting macroscopic yield strength of polycrystalline metals subjected to plastic forming by micro-macro de-coupling scheme A method of predicting macroscopic yield strength of polycrystalline metals subjected to plastic forming by micro-macro de-coupling scheme    2010 We introduce a method of predicting the macroscopic yield strength of polycrystalline metals subjected to plastic forming, which hinges on the reliability of the micro-macro decoupling scheme for solving the corresponding two-scale boundary value problem. A polycrystalline aggregate composed of several crystal grains is adopted as a periodic microstructure, namely unit cell, and is regarded as a numerical specimen for numerical material tests (NMTs) based on the homogenization theory. The NMTs a... 查看全文

325   Fluoride absorption from swallowed fluoride toothpaste Fluoride absorption from swallowed fluoride toothpaste    2006 ABSTRACT Absorption of fluoride (F) from ingested toothpastes was studied in rats, in adult humans and to some extent in children. The parameters analyzed were mainly 4-hour unabsorbed F in the rats and 9-hour urinary excretion in the humans. Five commercial and four experimental preparations were tested. The results indicate that the polishing agents calcium phosphate and calcium carbonate prevent a considerable fraction of the F content from being absorbed, whether this is present as F- or PO3... 查看全文

326   Appendix A: Instructions to Work Groups Appendix A: Instructions to Work Groups    2007 查看全文

327   Serial concatenation schemes for PSK waveforms vs. turbo codes Serial concatenation schemes for PSK waveforms vs. turbo codes Fred C. Kellerman    0 For radio communication systems, powerful error correction codes are necessary to operate in noisy and fading channel conditions. Iterative forward error correction schemes like Turbo codes can achieve near Shannon capacity performance on memory-less channels and also perform. well on correlated fading channels. The key to the excellent decoding performance of the Turbo coding systems is the BCJR algorithm in conjunction with the iterative processing of soft information. A very popular modulatio... 查看全文

328   Application of BP model in predicting porosity and compressive yield strength of porous NiTi alloy Application of BP model in predicting porosity and compressive yield strength of porous NiTi alloy    2006 Based on BP neural network theory, the model has been developed for the prediction of porosity and compressive yield strength of porous NiTi shape memory alloy(SMA) prepared by thermal explosion. The results indicate that the model is capable of reproducing the effects of changes in temperature, particle size of Ti and green density on product porosity and compressive yield strength. When temperature, particle size of Ti and green porosity changed, the product properties are predicted. Good agre... 查看全文

329   The pregnant patient: considerations in dental care The pregnant patient: considerations in dental care Ronald J. Hunt, Janis B. Eldredge and James D. Beck    2008 Although definitely not a disease, pregnancy poses a unique set of circumstances and necessary precautions for the dentist. The hormonal and anatomic changes produce effects that must be accounted for in providing dental care. As pregnancy is a transitory state, many elective dental procedures can be scheduled for completion after the baby is born. Pregnancy, however, does present the potential for dental problems that will require preventive strategies or actual treatment during pregnancy. Many... 查看全文

330   Oxygen permeation of various archetypes of oxygen membranes based on BSCF† Oxygen permeation of various archetypes of oxygen membranes based on BSCF† Hesternbsp;L. van Lingen, Jeroennbsp;K.nbsp;W. van de Mortel, Koennbsp;F.nbsp;W. Hekking, Florisnbsp    0 Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) tubes, capillaries, capillary modules and asymmetric membranes were prepared and tested for oxygen permeation in a dead end vacuum operation mode at temperatures up to 850 °C. The capillary module was built up by reactive air brazing (RAB) using 7 capillaries and a supply tube. Two machined discs were used as an end cap and as a connector plate. The oxygen permeation behaves according Wagner at small driving forces, but significant negative deviati... 查看全文

331   Time‐Dependent Losses in Prestressed, Continuous Composite Beams Time‐Dependent Losses in Prestressed, Continuous Composite Beams Alfarabi Sharif;Salah El‐Din F. Taher;P. K. Basu    0 Iterative one‐step, iterative step‐by‐step, and noniterative step‐by‐step approaches for calculating prestress losses due to shrinkage, creep, and steel relaxation for partially prestressed, continuous concrete/steel composite beams are presented. A simplified method that accounts for the aging effect on losses is also formulated. The method is based on exploiting the noniterative step‐by‐step approach to accumulate the losses through an infinite number of time intervals. It provides a simple y 查看全文

332   Effect of flow stress and yield-tensile ratio on tolerable defect size predictions Effect of flow stress and yield-tensile ratio on tolerable defect size predictions    1992 The selection of yield strength is a very important consideration in a fitness-for-purpose defect assessment. The use of the specified minimum yield strength (SMYS) value can result in very conservative or nonconservative defect sizes. This can be attributed to overmatching or undermatching weld metal yield strength compared to the SMYS. The principal concern is that the actual yield strengths are not always available. Another concern is that the yield strength is dependent on specimen size and ... 查看全文

333   The effect of ultimate-to-yield ratio on the bearing strength of bolted connections The effect of ultimate-to-yield ratio on the bearing strength of bolted connections    1999 An experimental study on the effect of end distance on the bearing strength of one-bolt and two-bolt lap connections was undertaken. Two different steels, one with high ultimate-to-yield stress ratio and the other with low ultimate-to-yield stress ratio, were used in the test program to determine the effect of steel strength on bearing capacity for various end distances and spacing. It was found that ultimate-to-yield stress ratios greater than 1.13 do not affect the strength at 6.35 mm displace... 查看全文

334   Effect of ultimate-to-yield ratio on the bearing strength of bolted connections Effect of ultimate-to-yield ratio on the bearing strength of bolted connections    1999 An experimental study on the effect of end distance on the bearing strength of one-bolt and two-bolt lap connections was undertaken. Two different steels, one with high ultimate-to-yield stress ratio and the other with low ultimate-to-yield stress ratio, were used in the test program to determine the effect of steel strength on bearing capacity for various end distances and spacing. It was found that ultimate-to-yield stress ratios greater than 1.13 do not affect the strength at 6.35 mm displace... 查看全文

335   Interactive effects of cold work, yield strength, and temperature on sulfide stress cracking Interactive effects of cold work, yield strength, and temperature on sulfide stress cracking    1990 In an effort to better define the interactions among cold work, yield strength, and temperature with respect to sulfide stress cracking (SSC) a statistically designed experiment was conducted using a 90 grade, sour service, low-alloy tubular steel. The SSC tests were conducted using stressed, notched, bent beam specimens exposed to the National Association of Corrosion Engineers (NACE) solution at various temperatures. The experimental strategy was based on a face-centered cube design, and regre... 查看全文

336   NDT tools for the prediction of strength and toughness parameters of pressure vessel steels NDT tools for the prediction of strength and toughness parameters of pressure vessel steels    1995 This paper develops nondestructive techniques for strength and toughness prediction as well as inspection procedures for predictive maintenance. It shows that a neural network functioning as a correlation supporting tool for micromagnetic materials characterization, i.e. strength and toughness prediction, combines some advantages with multiregression algorithms. The resulting rest standard deviation for the neural network approach is smaller than for multiregression algorithms. 查看全文

337   Ideal behavior. of sinter block densification and relation thereof to yield and strength in iron ore sintering Ideal behavior. of sinter block densification and relation thereof to yield and strength in iron ore sintering    2011 The authors assumed an ideal manner of sinter block densification due to increase in melt volume, and explained thereby changes in sinter strength and yield with operational factors such as ore porosity, CaO/Fe2O 3 ratio and coke content. Based on knowledge of liquid phase sintering, they drew polygonal lines to describe the change of sinter block strength with melt volume, which comprised two line segments for rapid and slow densification regions, where the position of broken point and the slop... 查看全文

338   Facile Access to Chiral Ketones through Metal-Free Oxidative CC Bond Cleavage of Aldehydes by O2† Facile Access to Chiral Ketones through Metal-Free Oxidative CC Bond Cleavage of Aldehydes by O2† Dr. Bhoopendra Tiwari, Dr. Junmin Zhang and Prof.;Dr. Yonggui Robin Chi    2012 查看全文

339   Yield interaction equations for nominal bending strength of curved I-girders Yield interaction equations for nominal bending strength of curved I-girders    1997 Horizontally curved I-girders are subjected to combined vertical bending and torsion under gravity loading alone. The torsional behavior. of open I-shaped girders is commonly and conveniently equated to self-equilibrating lateral bending moments in the flanges. The interaction of vertical bending and this lateral flange bending effectively reduces the vertical moment carrying capacity of the section. Yield interaction equations for predicting the nominal bending strength of horizontally curved s... 查看全文

340   Computer simulation of the yield strength evolution in Cu-precipitation strengthened ferritic steel Computer simulation of the yield strength evolution in Cu-precipitation strengthened ferritic steel    2010 During ageing of steel containing a few percent Cu, a maximum increase of hardness and strength can be observed after several hours of annealing at around 500-550°C. This strength increase is caused by small coherent bcc-Cu-precipitates of 2-3nm diameter. For consistent computer simulations of the early stages of precipitation, it is shown that variations in the equilibrium Fe-content of the bcc-Cu nuclei must be taken into account. The simulated precipitation parameters are compared to expe... 查看全文

341   Fracture behavior. and strength of stepped-lap bonded joint with adhesive resin under tensile loading Fracture behavior. and strength of stepped-lap bonded joint with adhesive resin under tensile loading    1996 Nonlinear fracture behavior. of stepped-lap bonded joints is studied. The joints used have adherends of eight kinds of metals: three of carbon steel, four of aluminum alloy and one of brass. The joints also have various thicknesses, lap lengths and step numbers. The effect of Young's modulus and yield strength of adherend material on the joint strength is calculated by means of elastoplastic finite-element analysis. It is found that the strength of the joint which yields at an adherend corner is... 查看全文

342   HBV plus HCV, HCV plus HIV, HBV plus HIV HBV plus HCV, HCV plus HIV, HBV plus HIV James S. Park, Neeraj Saraf;Douglas T. Dieterich    2006 Coinfection of hepatitis C virus (HCV), hepatitis B virus (HBV), and HIV is common due to shared modes of transmission. These coinfections accelerate the course of chronic liver disease and facilitate progression to cirrhosis and hepatocellular carcinoma. The viral interactions between these viruses are complex, and their treatment may be challenging for clinicians. 查看全文

343   Effect of yield strength to elastic modulus ratio on finite element based plastic loads for elbows under bending Effect of yield strength to elastic modulus ratio on finite element based plastic loads for elbows under bending    2008 This paper quantifies the effect of the yield strength-toelastic modulus ratio (yield strain) on plastic loads (defined by the twice-elastic-slope according to the ASME code) for 90° elbows under in-plane and out-of-plane bending. Results are based on exten sive and systematic FE limit analyses assuming elastic-perfectly plastic materials. Based on FE results, a simple approximation of plastic loads of pipe bends, incorporating the yield strength-to-elastic modulus ratio effect, is proposed.... 查看全文

344   Checkpoint Processing and Recovery: Checkpoint Processing and Recovery: Towards Scalable Large, Haitham Akkary, Ravi Rajwar, Srikanth T. Srinivasan    2003 Large instruction window processors achieve high performance by exposing large amounts of instruction level parallelism. However, accessing large hardware structures typically required to buffer and process such instruction window sizes significantly degrade the cycle time. This paper proposes a novel Checkpoint Processing and Recovery (CPR) microarchitecture, and shows how to implement a large instruction window processor without requiring large structures thus permitting a high clock frequency... 查看全文

345   Yield strength asymmetry predictions from polycrystal elastoplasticity Yield strength asymmetry predictions from polycrystal elastoplasticity    1999 Since the 1960s, it has been known that elastoplastic polycrystal models predict asymmetries in the yield strength for polycrystals that have been prestrained. After prestraining in tension, a model polycrystal exhibits Bauschinger-like behavior. in that it yields in compression at a lower stress magnitude than in tension. Furthermore, the knee of the reloading stress-strain curve is more gradual for compression than for tension. The origins of these behaviors reside in the assumption that links... 查看全文

346   Hen egg yolk and skinned krill as possible foods for rearing leptocephalus larvae of Anguilla japonica Temminck & Schlegel Hen egg yolk and skinned krill as possible foods for rearing leptocephalus larvae of Anguilla japonica Temminck & Schlegel Kenji NOZAKA    2012 Usual diets for rearing leptocephalus larvae of Japanese eel Anguilla japonica include eggs of the endangered spiny dogfish Squalus acanthias (SE). We investigated the effects of alternative food materials, hen egg yolk (HEY) and exoskeleton-free (skinned) Antarctic krill (SAK), on the growth and survival of eel larvae. We found that feed comprising whole krill including exoskeleton (WAK) containing higher levels of fluoride (37.89 mg kg−1) was acutely toxic to eel larvae exposed... 查看全文

347   Artificial neural network model for the strength prediction of fully restrained RC slabs subjected to membrane action Artificial neural network model for the strength prediction of fully restrained RC slabs subjected to membrane action    2006 This paper develops an artificial neural network (ANN) model for uniformly loaded restrained reinforced concrete (RC) slabs incorporating membrane action. The development of membrane action in RC slabs restrained against lateral displacements at the edges in buildings and bridge structures significantly increases their load carrying capacity. The benefits of compressive membrane action are usually not taken into account in currently available design methods based on yield-line theory. By extendi... 查看全文

348   Evaluation of softened truss model for strength prediction of reinforced concrete squat walls Evaluation of softened truss model for strength prediction of reinforced concrete squat walls    2005 This paper evaluates the softened truss model and the softened strut-and-tie model for predicting shear strength of reinforced concrete squat walls. The prediction accuracy of analytical solutions is examined using the experimental data of 62 test shear walls available in the literature. It was found that the analytical solutions, which utilize the softening laws of cracked reinforced concrete under compression, can yield better estimations of shear strength. Further, the state of stresses in th... 查看全文

349   Towards a direct strength method for cold-formed steel beam-columns Towards a direct strength method for cold-formed steel beam-columns    2010 The objective of this paper is to directly examine the stability and strength of cold-formed steel beam-columns under their actual combined actions: axial and bending, biaxial bending, etc. The current approach to cold-formed steel beam-column design is based on simplified linear interaction formulas that are based on separate axial and flexural stability and strength determinations. Since stability is stress dependent the appropriate combinations are strongly cross-section dependent and direct ... 查看全文

350   Induction of the chick columella and its integration with the inner ear Induction of the chick columella and its integration with the inner ear Dr. Brian Hopkins, Yvonne L. Lems, Titia Van Wulfften Palthe, Jan Hoeksma, Otto Kardaun and George B    2012 Background: The auditory complex of the chick, like that of humans, is made of intimate and highly ordered connections between the inner ear, the middle ear, and the outer ear. Unlike mammals, the middle ear of chick has only one ossicle, known as the columella. The independent lineages of the two suggest that some mechanism must exist that ensures the connectivity between the inner ear and the columella; however, the basis of integration is not known. Results: Using quail-chick chimeras, we dem... 查看全文

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