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Consistent constitutive modeling of metallic target penetration using empirical, analytical, and numerical penetration models

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Defence Technology（防务技术） 2016年第2期12卷 201-213页

作者： John(Jack) P.RIEGEL III David DAVISON R3 Technology Inc. 7324 Fountain Spring Ct. Shock Transients Inc.

Historically, there has been little correlation between the material properties used in(1) empirical formulae,(2) analytical formulations, and(3) numerical models. The various regressions and models may each provide excellent agreement for the depth of penetration into semi-infinite targets. But the input parameters for the empirically based procedures may have little in common with either the analytical model or the numerical model. This paper builds on previous work by Riegel and Anderson(2014) to show how the Effective Flow Stress(EFS) strength model, based on empirical data, can be used as the average flow stress in the analytical Walker–Anderson Penetration model(WAPEN)(Anderson and Walker,1991) and how the same value may be utilized as an effective von Mises yield strength in numerical hydrocode simulations to predict the depth of penetration for eroding projectiles at impact velocities in the mechanical response regime of the materials. The method has the benefit of allowing the three techniques(empirical, analytical, and numerical) to work in tandem. The empirical method can be used for many shot line calculations, but more advanced analytical or numerical models can be employed when necessary to address specific geometries such as edge effects or layering that are not treated by the simpler methods. Developing complete constitutive relationships for a material can be costly. If the only concern is depth of penetration, such a level of detail may not be required. The effective flow stress can be determined from a small set of depth of penetration experiments in many cases, especially for long penetrators such as the L/D = 10 ones considered here, making it a very practical approach. In the process of performing this effort, the authors considered numerical simulations by other researchers based on the same set of experimental data that the authors used for their empirical and analytical assessment. The goals were to establish a baseline with a full constitut

关键词：本构模型渗透模型数值模型金属靶材料性质流动应力程序模拟数值计算

Toll-like receptor agonists shape the immune responses to a mannose receptor-targeted cancer vaccine

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Cellular & Molecular Immunology 2015年第6期12卷 719-728页

作者： Li-Zhen He Jeffrey Weidlick Crystal Sisson Henry C Marsh Tibor Keler Celldex Therapeutics Inc. Hampton N J USA and Celldex Therapeutics Inc. Needham MA USA

Previous studies have documented that selective delivery of protein antigens to cells expressing mannose receptor （MR） can lead to enhanced immune responses. We postulated that agents that influenced the MR expression level, and the activation and migration status of MR-expressing antigen presenting cells, would modulate immune responses to MR-targeted vaccines. To address this question, we investigated the effect of clinically used adjuvants in human MR transgenic （hMR-Tg） mice immunized with an MR-targeting cancer vaccine composed of the human anti-MR monoclonal antibody B 11 fused with the oncofetal protein, human chorionic gonadotropin beta chain （hCGβ）, and referred to as B 11-hCGβ. We found that humoral responses to low doses of B11-hCGβ could be enhanced by prior administration of GM-CSF, which upregulated MR expression in vivo. However, co-administration of the Toll-like receptor （TLR） agonists, poly-ICLC and/or CpG with B11-hCGβ was required to elicit Thl immunity, as measured by antigen-specific T-cell production of IFN-γ. The TLR agonists were shown to inc.ease the number of vaccine-containing cells in the draining lymph nodes of immunized hMR-Tg mice. In particular, with B11-hCGβand poly-ICLC, a dramatic inc.ease in vaccine-positive cells was observed in the T-ceU areas of the lymph nodes, compared to the vaccine alone or combined with GM-CSF. Importantly, the absence of the TLR agonists during the priming immunization led to antigen-specific tolerance. Therefore, this study provides insight into the mechanisms by which adjuvants can augment immune responses to B11-hCGβ and have implications for the rationale design of clinical studies combining MR-targeted vaccination with TLR agonists.

关键词： GM-CSF hCGβ mannose receptor Toll-like receptor agonists

Crystal Structures of Human Dipeptidyl Peptidase Ⅳ in its Apo and Diprotin B-complexed Forms

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Acta Biochimica et Biophysica Sinica 2007年第5期39卷 335-343页

作者： Hajime H1RAMATSU Kiyoshi KYONO Atsushi YAMAMOTO Kazuhiko SAEKI Hideaki SHIMA Shigeru SUGIYAMA Koji INAKA Ryo SHIMIZU Tanabe Seiyaku Co. Ltd Osaka 532-8505 Japan Aphoenix inc. Tokyo 150-0002 Japan Maruwa Food Industries inc. Nara 639-1123 Japan Mol Logics Inc. Kyoto 619-0237 Japan Maruwa Food Industries inc. Nara 639-1123 Japan

Dipeptidyl peptidase Ⅳ (DPPIV), which belongs to the prolyl oligopeptidase family of serine proteases, is known to have a variety of regulatory biological functions and has been shown to be implicated in type 2 diabetes. It is therefore important to develop selective human DPPIV (hDPPIV) inhibitors. In this study, we determined the crystal structure of apo hDPPIV at 1.9 A resolution. Our high-resolution crystal structure of apo hDPPIV revealed the presence of sodium ion and glycerol molecules at the active site. In order to elucidate the hDPPIV binding mode and substrate specificity, we determined the crystal structure of hDPPIV-diprotin B (Val-Pro-Leu) complex at 2.1 A resolution, and clarified the difference in binding mode between diprotin B and diprotin A (Ile-Pro-Ile) into the active site of hDPPIV. Comparison between our crystal structures and the reported apo hDPPIV structures revealed that positively charged functional groups and conserved water molecules contributed to the interaction of ligands with hDPPIV. These results are useful for the design of potent hDPPIV inhibitors.

关键词： dipeptidyl peptidase Ⅳ diprotin B serine protease crystal structure water molecule

SUSTAINABLE SITE DEVELOPMENT

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Journal of Green Building 2006年第1期1卷 9-20页

作者： Bruce A.Hendee BHA Design inc.

INTRODUCTION Two weeks ago I went for a trail run at Coyote *** about five miles south of Fort Collins,the Coyote Ridge trail is about a seven mile round trip and takes runners up a geological hogback and then down into a pristine *** I was in a system perfectly balanced but not static;one in which all systems were in a state of dynamic interaction but always shifting in a way that ensured *** was moving in a balanced *** was enough food,water,and shelter produced,but there was no *** I,standing in the valley,had an opportunity to add to the balance.

关键词： trail valley shifting

The practice of mine ventilation engineering

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International Journal of Mining Science and Technology 2015年第2期25卷 165-169页

作者： Wallace Keith Prosser Brian Stinnette J.Daniel Mine Ventilation Services Inc.

The practice of ventilation is continually evolving with new technological advances developed in the mining *** recent years the advances in diesel engine technologies,ventilation modeling software,and ventilation management capacities have redefined the historical methods used to evaluate *** advances re-evaluate previous methods used to calculate the airflow requirements for the dilution of diesel exhaust *** software has become an integral part of planning and developing ventilation systems in partnership with graphical mine design software packages to generate realistic representations of the *** advances in ventilation control strategies through remote sensors and monitoring capabilities have been developed to results in cost *** there has been much advancement in mine ventilation technology,the practices and basic ventilation princ.pals enacted through the ventilation engineer cannot be placated with technological advances only.

关键词： Modern ventilation Ventilation on demand Diesel Airflow evaluation Monitoring system

Effects of essential oils on economically important characteristics of ruminant species:A comprehensive review

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Animal Nutrition 2024年第1期16卷 1-10页

作者： Cara Wessels Wells MicroBios Inc.HoustonUnited States

Essential oils derived from plants can provide biological impacts to livestock *** studies researching essential oils in livestock have investigated various essential oils for prevention and treatment of microbial infection and parasites as well as to enhance milk production,animal performance and rumen *** the availability of several commercial products containing essential oils to promote animal health and production,the vast amount of essential oils,modes of application,and effective concentrations of the essential oils suggest there are more opportunities for essential oils to be utilized in commercial livestock production and veterinary *** objective of this review is to contribute to the understanding of the value that essential oils can provide to the ruminant diet and to examine the biological impact of various essential oils on economically important production traits of ruminant species.

关键词： Essential oils Ruminant diet Non-antibiotic therapy

Ultraviolet and visible upconversion luminescence of Tm(0.1)Yb(5):FOV oxyfluoride nanophase vitroceramics

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Science China(Physics,Mechanics & Astronomy) 2008年第12期51卷 1868-1876页

作者： N. SAWANOBOI M. OHTSUKA Sumita Optical Glass Inc. Japan

The ultraviolet upconversion luminescence of Tm3+ ions sensitized by Yb3+ ions in oxyfluoride nanophase vitroceramics when excited by a 975 nm diode laser was studied. An ultraviolet upconversion luminescence line positioned at 363.6 nm was found. It was attributed to the fluorescence transition of 1D2→3H6 of Tm3+ ion. Sev- eral visible upconversion luminescence lines at 450.7 nm, (477.0 nm, 462.5 nm), 648.5 nm, (680.5 nm, 699.5 nm) and (777.2 nm, 800.7 nm) were also found, which result respectively from the fluorescence transitions of 1D2→3F4, 1G4→3H6, 1G4→3F4, 3F3→3H6 and 3H4→3H6 of Tm3+ ion. The careful measurement and analysis of the variation of upconversion luminescence intensity F as a function of the 975 nm pumping laser power P prove that the upconversion luminescence of 1D2 state is partly a five-photon upconversion luminescence, and the upconversion lumines- cence of 1G4 state and 3H4 state are respectively the three-photon and two-photon upconversion luminescence. The theoretical analysis suggested that the upcon- version mechanism of the 363.6 nm 1D2→3H6 upconversion luminescence is partly the cross energy transfer of {3H4(Tm3+)→3F4(Tm3+), 1G4(Tm3+)→1D2(Tm3+)} and {1G4(Tm3+)→3F4(Tm3+), 3H4(Tm3+)→1D2(Tm3+)} between Tm3+ ions. In addition, the upconversion luminescence of 1G4 and 3H4 state results respectively from the se- quential energy transfer {2F5/2(Yb3+)→2F7/2(Yb3+), 3H4(Tm3+)→1G4(Tm3+)} and {2F5/2(Yb3+) →2F7/2(Yb3+), 3F4(Tm3+)→3F2(Tm3+)} from Yb3+ ions to Tm3+ ions.

关键词： upconversion luminescence ultraviolet oxyfluoride nanophase vitroceramics saturation Tm3+ ion Yb3+ ion energy transfer

PROPERTIES, WELDABILITY AND APPLICATIONS OF ADVANCED WROUGHT SUPERALLOYS FOR GAS TURBINE ENGINES

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Acta Metallurgica Sinica(English Letters) 2005年第1期18卷 1-14页

作者： D.L. Klarstrom V.R. Ishwar M.D. Rowe Haynes International inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USA

Alloy selection and alloy design both require consideration of an array of material attributes, inc.uding in-service properties, weldability and fabricability. Critical properties of advanced wrought superalloys for gas turbine applications inc.ude high temperature strength, thermal stability, oxidation resistance and fatigue resistance. In this paper, the properties of twelve wrought solid-solution-strengthened and six age-hardenable superalloys are compared. Weldability is an important attribute and can be a major limiting factor in the use of certain alloys. Weldability test methods are discussed and the resistance of alloys to solidification cracking and strain-age cracking is compared. The use of weldability testing in the development of modern wrought su-peralloys is discussed with several examples cited. Finally, alloy selection for gas turbine components is outlined, taking into account both alloy properties and fabricability.

关键词： wrought superalloys mechanical properties strain-age cracking of weldments selection and application of wrought superalloys

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