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State of the Art Treatment of Non-Ferrous Castings 3-in-l Heat Treatment Systems Combine Foundry Processes

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材料热处理学报 2004年第5期25卷 552-554页

作者： Volker R. Knobloch CEC - Consolidated Engineering Co. Inc.

The interior of a high-pressure die-casting is of an unsatisfactory quality. Engine blocks made with this die casting process show lower specific engine performance. Pressure die-casting can hardly be heat treated for obvious reasons. PSM (Precision Sand Molds) process uses sand and organic binder to generate a mold and even allows the manufacturing of complex diesel engine blocks in aluminum alloys. Combined technologies are available for semi-permanent mold castings with cores and castings made in Precision Sand Molds with organic binders. Castings are placed into the special heat treatment furnace immediately after pouring without the operations in stand alone machinery. This patented Sand Lion 3- in-1 technology processes hot castings and carries out three (3) foundry processes simultaneously in one (1) automated machine: 1) De-coring and sand removal; 2) Thermal sand reclamation; 3) Solution heat treatment of castings. The combination of several main casting processes is reflected in significant reductions of energy consumption, of production costs, and improving the quality of the castings. Audits in foundries using the 3-in-l process showed an average reduction in production costs of more than 30%.

关键词：沙模固溶热处理集成铸造流化床

Coal pillar mechanics of violent failure in U.S. Mines

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International Journal of Mining Science and Technology 2017年第3期27卷 387-392页

作者： Maleki Hamid Maleki Technologies Inc. Spokane WA 99223 USA

This paper seeks to enhance the understanding that the horizontal stresses build up and release during coal pillar loading and unloading(post-failure) drawing upon three decades of observations, geomechanical monitoring and numerical modeling in bump-prone U.S. mines. The focus is on induced horizontal stress in mine pillars and surrounding strata as highly stressed pillars punch into the roof and floor, causing shear failure and buckling of strata; under stiff stratigraphic units of some western US mines, these events could be accompanied by violent failure of pillar cores. Pillar punching eventually results in tensile stresses at the base of the pillar, facilitating transition into the post-failure regime; this transition will be nonviolent if certain conditions are met, notably the presence of interbedded mudstones with low shear strength properties and proper mine designs for controlling seismicity and dynamic loads. The study clearly shows high confining stress build-up in coal pillars resulting in up to twice higher peak vertical stress and high strain energy accumulations in some western US mines in comparison with peak stresses predicted using common empirical pillar design methods. It is the unstable release of this strain energy that can cause significant damage resulting from pillar dilation and ground movements. These forces are much greater than the capacity of most common internal support systems, resulting in horizontal stressinduced roof falls locally, in mines under unremarkable far-field horizontal stress. Attention should be placed on pillar designs as inc.easing support density may prove to be ineffective. This mechanism is analyzed using field measurements and generic finite-difference stress analyses. The study confirms the higher load carrying capacity of confinement-controlled coal seams in comparison with structurally controlled coal seams. Such significant differences in confining stresses are not taken into account when estimating peak pil

关键词： Rockburst and coal bumps Field measurements Stress analysis Mechanics Horizontal stress

Monogamous nature of symmetric N-qubit states of the W class: Concurrence and negativity tangle

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Chinese Physics B 2015年第11期24卷 85-91页

作者： P.J.Geetha K.O.Yashodamma Sudha Department of Physics Kuvempu University Inspire Institute inc.

Using Majorana representation of symmetric N-qubit pure states, we have examined the monogamous nature of the family of states with two-distinc. spinors, the W class of states. We have evaluated the N-concurrence tangle and showed that all the states in this family have vanishing concurrence tangle. The negativity tangle for the W class of states is shown to be non-zero, illustrating the fact that the concurrence tangle is always lesser than or equal to the negativity tangle in a pure N-qubit state.

关键词： monogamy of quantum entanglement Majorana representation of symmetric pure states concur-rence tangle negativity tangle

Hardware Materials in Molten Carbonate Fuel Cell:A Review

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Acta Metallurgica Sinica(English Letters) 2017年第4期30卷 289-295页

作者： Ling Chen Chao-Yi Yuh FuelCell Energy Inc.DanburyCT 06813USA

The high-temperature molten carbonate fuel cell is an ultra-clean and highly efficient power generator. It is operated at - 550-650 ℃, which is considered optimal in facilitating fast fuel cell reaction kinetics, utilizing waste heat efficiently, and allowing use of commercial construction materials. Commercial MW-size （mega watt） power plants of FuelCell Energy products have already been deployed worldwide. Metallic hardware materials are extensively utilized and may experience high-temperature reducing and oxidizing atmospheres in the presence of molten alkali carbonate electrolyte. Material selections are founded on many decades of focused research and development and field experience. Results to date show that the baseline stack module materials meet 5-year life goal and BOP （balance of plant） construction materials meet 20-year life goal. Material durability is well understood, and solutions are available to further extend the durability. This paper will review hardware materials experience and development approaches that would further reduce cost and extend life.

关键词： Molten carbonate fuel cell High-temperature materials Corrosion

Combining Aluminum Heat Treat with Hot Isostatic Pressing: A Comparison of Structure, Properties, and Processing Routes for a Cast AI-Si-Mg Alloy

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材料热处理学报 2004年第5期25卷 546-551页

作者： Stephen J. Mashl Body cote HIP inc. Andover Massachusetts USA

Bodycote researchers have successfully demonstrated that a T6 heat treatment can be integrated with Densal?, a proprietary, aluminum specific, hot isostatic pressing (HIP) process. In this combined operation, at least a portion of the solution heat treatment is conducted at elevated pressure. During development, two issues, adiabatic cooling during depressurization and a possible variation in the kinetics of homogenization resulting from conducting the solution heat treat at elevated pressure were perceived as factors which could alter the heat treat response from that seen in conventional processing. This paper reviews the results of experiments performed to Al-Si-Mg (A356.0) castings subjected to both combined and conventional processing routes. Results indicate that the combined HIP and heat treat process is an efficient means of achieving a microstructure characteristic of a conventionally T6 processed material while eliminating porosity within the casting. Further, the fatigue life of an A356.0 casting processed using the combined cycle can be improved by more than an order of magnitude over the as-cast and T6 treated component.

关键词： Al-Si-Mg合金热处理热等静压缩 HIP 机械性质疲劳寿命

High-quality aluminum turbocharger impellers produced by thixocasting

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Transactions of Nonferrous Metals Society of China 2010年第9期20卷 1786-1791页

作者： G.WALLACE A.P.JACKSON S.P.MIDSON Q.ZHU Aluminum Complex Components Inc The Midson Group Inc. Cummins Turbo Techno logies

The thixocasting process was chosen to produce the impellers as it is capable of producing castings with extremely high internal *** cut from the DC cast bars are re-heated to the semi-solid casting temperature, and a specially-designed runner and gating system is used to prevent oxide from the surface of the slugs from becoming inc.rporated into the *** technology used to produce the semi-solid impellers is described in *** semi-solid cast impellers, produced from an Al-Si-Mg-Cu alloy, are heat treated to the T6 *** from testing are presented demonstrating that the impellers are free of porosity and other internal *** mechanical property and fatigue data are presented showing that the semi-solid impellers have better properties than impellers produced by conventional casting and similar properties to forged and machined impellers.A short study is also described which identified suitable processing parameters to minimize hot tearing in the complex-shaped turbocharger impellers semi-solid cast from alloy *** surfaces of the impellers were examined using penetrant testing, and the results of modifying processing parameters on the propensity for surface cracking are *** aging study was performed to identify optimum mechanical strength.

关键词： semi-solid casting turbocharger impeller fatigue properties alloy 201

Tools to identify the men with prostate cancer most appropriate for active surveillance？

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Asian Journal of Andrology 2014年第1期16卷 97-98页

作者： Robert H Getzenberg GTx inc. Memphis TN USA

Agreat deal of effort is underway in order .to identify those men with prostatecancer felicitous for active surveillance with greater precision than that afforded to us today. In the manuscript by Irshad et al. the authors evaluate a novel set of genes associated with senescence and aging as tools that can provide guidance regarding the indolent nature of an individual＇s prostate cancer with validation using both mRNA and protein analyses. While additional studies are required to understand the full impact of these findings, the innovative approach taken enhances our understanding of distinc. phenotypes of prostate cancer.

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Selective androgen receptor modulators for the treatment of late onset male hypogonadism

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Asian Journal of Andrology 2014年第2期16卷 256-261,I0009页

作者： Christopher C Coss Amanda Jones Michael L Hancock Mitchell S Steiner James T Dalton GTx Inc. Memphis Tennessee USA.

Several testosterone preparations are used in the treatment of hypogonadism in the ageing male. These therapies differ in their convenience, flexibility, regional availability and expense but share their pharmacokinetic basis of approval and dearth of long-term safety data. The brevity and relatively reduced cost of pharmacokinetic based registration trials provides little commercial inc.ntive to develop improved novel therapies for the treatment of late onset male hypogonadism. Selective androgen receptor modulators （SARMs） have been shown to provide anabolic benefit in the absence of androgenic effects on prostate, hair and skin. Current clinical development for SARMs is focused on acute muscle wasting conditions with defined clinical endpoints of physical function and lean body mass. Similar regulatory clarity concerning clinical deficits in men with hypogonadism is required before the beneficial pharmacology and desirable pharmacokinetics of SARMs can be employed in the treatment of late onset male hypogonadism.

关键词： hypogonadism late onset hypogonadism selective androgen receptor modulators testosterone

Development of Nanopowder Synthesis Using Induction Plasma

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Plasma Science and Technology 2010年第2期12卷 188-199页

作者： Richard DOLBEC Jerzy JUREWICZ Maher BOULOS Tekna Plasma Systems inc. 2935 Industrial Boulevard Sherbrooke

The application of induction plasma technology developed for the synthesis of nano- metric powders is summarized. A brief description of the scientific basis for the induction plasma processes is given, followed by the presentation of an induction plasma system developed by Tekna, together with various examples of the nanopowders synthesized using its facilities. The advantages of the induction plasma process over alternative techniques and its adaptability into industrial- scale operation is particularly illustrated. Some specific issues related to the nanopowder synthesis process are also discussed.

关键词： nano-material nanopowders induction plasma