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大模数齿轮感应加热表面淬火结果的计算预测

热处理 2013年第4期28卷 35-40页

作者： Ф.В.Ъезменов Е.М.иевлев 张家雄 Γ.Санкт-Петербург ВНИИТВЧ Фгуп 中国一拖集团有限公司

为使某特定钢材齿轮类零件经过热处理获得一定表面硬度、沿齿廓分布的淬硬层深度等性能,就必须研发强化工艺和实施该工艺的设备。使大模数齿轮获得要求的感应加热质量的问题文献[1]已有论述,但未对同样是淬火过程的重要组成部分的淬火... 详细信息

为使某特定钢材齿轮类零件经过热处理获得一定表面硬度、沿齿廓分布的淬硬层深度等性能,就必须研发强化工艺和实施该工艺的设备。使大模数齿轮获得要求的感应加热质量的问题文献[1]已有论述,但未对同样是淬火过程的重要组成部分的淬火冷却方法予以分析。

关键词：感应加热表面淬火齿轮模数淬硬层电流频率比功率

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洛杉矶盆地中的地震波形模拟

世界地震译丛 1996年第3期27卷 36-53页

作者： C.W.Scrivner D.v.Hehnberger 梁凯利山东省地震局

最近发生的几次地震与洛杉矶盆地邻近,这为提取盆地对地震波传播的影响提供了机会。1987年10月4日发生的惠蒂尔峡谷地震序列中的一次余震(m_L=5.3)和1991年4月28日发生的谢拉马德雷主震(m_L=5.8)在盆地最深处各台站所构成的方位角相近... 详细信息

最近发生的几次地震与洛杉矶盆地邻近,这为提取盆地对地震波传播的影响提供了机会。1987年10月4日发生的惠蒂尔峡谷地震序列中的一次余震(m_L=5.3)和1991年4月28日发生的谢拉马德雷主震(m_L=5.8)在盆地最深处各台站所构成的方位角相近。盆地各台站所得到10月4日余震记录有一显著特点,即S,SS等多重反射波振幅很大。切向分量上其振幅高达直达S波振幅的2倍。在小于25km的这样一个小范围内,需要一个水平方向的地震波速度梯度,使地震射线足够快地发生弯曲,以形成这些多重反射波。本文采用了一种正演模拟方法,用有限差分数字技术得到双力偶点源震源机制。以洛杉矶盆地东端一个近代地质横断面为依据的模型生成的震相比在地震记录中所看到的震相要多。而以顶部几层中低剪切速度的倾斜分层为依据的较简单的模型,与资料拟合得更好。为了符合直达P波、直达S波和第一个多重S波之间的到时差,要改变地震速度、深度、层的倾斜等输入参数。尽管第一个多重波的相位与资料不符,但直达S波和第一个多重S波初动脉冲的到时、振幅模拟得很好。除了在邻近盆地边缘的距离内,盆地模型中加进陡峭的西部边界,对合成波形没有多大影响。在盆地最深部分SS波的振幅是最大的,比直达S波大2倍。从东北到西南,尾波持续时间从8s增加到20多秒。谢拉马德雷主震发生在惠蒂尔峡谷地震序列的东北部25km左右。惠蒂尔峡谷的模型被扩展到这一距离范围,在惠蒂尔地震和谢拉马德里地震震中之间设置一浅盆地,以模拟圣加布里埃尔沉积盆地。虽然由深盆地边缘产生的震相仍然控制着合成波形,但该模型产生了一个长的尾波。这一研究表明:穿过深沉积盆地,频率达1Hz的若干特定震相可以用二维地震波速度模型来解释。

关键词：地震波波形模拟

Recent Ⅳ-drug users with chronic hepatitis C can be efficiently treated with daily high dose induction therapy using consensus interferon:An open-label pilot study

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World Journal of Gastroenterology 2007年第4期13卷 579-584页

作者： Th Witthoeft m Fuchs D Ludwig University Hospital Schleswig- Holstein Campus Luebeck Department of Medicine I Division of Gastroenterology Luebeck Germany University Hospital Ulm Department of Medicine I Ulm Germany

AIm： To investigate the use of high dose consensusinterferon in combination with ribavirin in former iv drug users infected with hepatitis C. mETHODS： We started, before pegylated （PEG）interferons were available, an open-label study to investigate the efficacy and tolerability of high dose induction therapy with consensus interferon （CIFN） and ribavirin in treatment of naiive patients with chronic hepatitis C. Fifty-eight patients who were former iv drug users, were enrolled receiving 18 μg of CIFN daily for 8 wk, followed by 9 μg daily for up to wk 24 or 48 and 800 mg of ribavirin daily. End point of the study was tolerability and eradication of the virus at wk 48 and sustained virological response at wk 72. RESULTS： more than 62% of patients responded to the treatment with CIFN at wk 24 or 48, respectively, showing a negative qualitative PCR [genotype 1 fourteen patients （56%）, genotype 2 five （50%）, genotype 3 thirteen （87%）, genotype 4 four （50%）]. Forty-eight percent of genotype 1 patients showed sustained virological response （SvR） six months after the treatment. CONCLUSION： CIFN on a daily basis is well tolerated and side effects like leuko- and thrombocytopenia are moderate. End of therapy （EOT） rates are slightly lower than the newer standard therapy with pegylated interferons. CIFN on a daily basis might be a favourable therapy regimen for patients with GTI and high viral load or for non-responders after failure of standard therapy.

关键词： Consensus-interferon Hepatitis C Poly-merase chain reaction Sustained virological response

Nutrient cycling and greenhouse gas emissions from soil amended with biochar-manure mixtures

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Pedosphere 2021年第2期31卷 289-302页

作者： Carlos m.ROmERO Chunli LI Jen OWENS Gabriel O.RIBEIRO Tim A.mCALLISTER Erasmus OKINE Xiying HAO Agriculture and Agri-Food Canada Lethbridge Research and Development CentreLethbridgeAlberta T1J 4B1(Canada) Department of Biological Sciences Faculty of Arts&SciencesUniversity of LethbridgeLethbridgeAlberta T1K 3M4(Canada) Department of Animal and Poultry Science University of SaskatchewanSaskatoonSaskatchewan S7N 5A8(Canada)

Integrating biochar into cattle diets has recently emerged as a potential management practice for improving on-farm ***,information concerning the cycling of biochar-manure mixtures is scarce.A 70-d incubation experiment was conducted within two surface(0–15 cm)mollisols with contrasting textures,i.e.,sandy clay loam(Raymond)and clayey(Lethbridge),to evaluate the effects of biochar(3 mg ha^(-1))on cumulative greenhouse gas(GHG)emissions and related fertility attributes in the presence or absence of cattle manure(120 mg ha^(-1)).Five treatments were included:i)non-amended soil(control,CK),ii)soil amended with pinewood biochar(B),iii)soil amended with beef cattle manure(m)(manure from cattle on a control diet),iv)soil amended with biochar-manure(Bm)(manure from cattle on a control diet,with pinewood biochar added at 20 g kg^(-1)of diet dry matter),and v)soil amended with B and m at the aforementioned rates(B+m).A total of 40 soil columns were prepared and incubated at 21℃and 60%–80%water-holding *** average,total CO_(2)fluxes increased by 2.2-and 3.8-fold under manure treatments(i.e.,m,Bm,and B+m),within Raymond and Lethbridge soils,respectively,relative to CK and ***,total CH4 fluxes were the highest(Pmond soil under B+m and Bm relative to CK and B,and in Lethbridge soil under m and Bm relative to CK and *** Lethbridge soil,application of Bm increased cumulative N_(2)O emissions by 1.8-fold relative to *** 70-d incubation,amendment with Bm increased(Pvailability in Raymond and Lethbridge soils compared with B.A similar pattern was observed for water-extractable organic carbon in both soils,with Bm augmenting(Pver CK and *** can be concluded that biochar,manure,and/or biochar-manure have contrasting short-term effects on the biogeochemistry of *** relatively low application rates,biochar does not necessarily counterbalance manure-derived inpu

关键词： animal husbandry black carbon carbon dioxide methane Orthic Black Chernozem soil fertility

Unbiased Diffusion to Escape Complex Geometries: Is Reduction to Effective One-Dimensional Description Adequate to Assess Narrow Escape Times?

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Applied mathematics 2014年第8期5卷 1218-1225页

作者： Yoshua Chávez Guillermo Chacón-Acosta marco-vinicio vázquez Leonardo Dagdug Applied mathematics and Systems Department Universidad Autónoma Metropolitana-Cuajimalpa México DF México Chemistry Department Universidad Autónoma Metropolitana-Iztapalapa México DF México Physics Department Universidad Autónoma Metropolitana-Iztapalapa México DF México

This study is devoted to unbiased diffusion of point Brownian particles inside a tube of varying cross-section (see Figure 1). An expression for the mean survival time, , of the particles inside the tube is obtained in terms of the bulk diffusion constant, D0 and the system’s geometrical parameters, namely, the tube’s axial semi-length, L, the minor radius, , and the slope of the tube’s wall, . Our expression for correctly retrieves the limit behavior of the system under several conditions. We ran monte Carlo numerical simulations to compute the mean survival time by averaging the survival time of 5 × 104 trajectories, with time step t = 10-6, D0 = 1, and L = 1. The simulations show good agreement with our model. When the geometrical parameters of this system are varied while keeping constant the tube’s enclosed volume, it resembles the problems of Narrow Escape Time (J. Chem. Phys. 116(22), 9574 (2007)). A previous study on the use of the reduction to effective one-dimension technique (J. mod. Phys. 2, 284 (2011)) in complex geometries has shown excellent agreement between the theoretical model and numerical simulations. However, in this particular system, the general assumptions of the Hill problem are seemingly inapplicable. The expression obtained shows good agreement with our simulations when 0 ≤ ≤ 1, but fails when grows larger. On the other hand, some errors are found when 0, but the expression holds reasonably well for a broad range of values of . These comparisons between simulations and theoretical predictions, and the expressions obtained for , are the main results of this work.

关键词： Component Formatting Style Styling Insert

Effect of layer sliding on the interfacial electronic properties of intercalated silicene/indium selenide van der Waals heterostructure

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Communications in Theoretical Physics 2022年第3期74卷 112-118页

作者： masood Yousaf m W Younis Ahmed S Jbara m Junaid Iqbal Khan G murtaza m A Saeed Department of Physics Division of Science and TechnologyUniversity of EducationLahore54770Pakistan Department of Chemistry University of Management and TechnologyC-IIJohar TownLahore54770Pakistan mathematics Department College of Education for Pure ScienceAl-Muthanna UniversitySamawah66001Iraq Laboratory of Theoretical and Experimental Physics Department of PhysicsBahauddin Zakariya UniversityMultan60800Pakistan materials modelling Lab Department of PhysicsIslamia College PeshawarKPPakistan Department of mathematics&Natural Sciences Prince Mohammad Bin Fahd UniversityP.O.Box 1664Alkhobar 31952Saudi Arabia

methods capable of tuning the properties of van der Waals(vdW)layered materials in a controlled and reversible manner are highly *** electronic properties of two-dimensional vdW heterostructure consisting of silicene and indium selenide(InSe)have been calculated using density functional theory-based computational ***,in order to vary the aforementioned properties,silicene is slid over a InSe layer in the presence of Li *** intercalation of the heterostructure,the buckling parameter associated with the corrugation of silicene decreases from 0.44A to 0.36A,whereas the InSe structure remains *** energy scans reveal a significant increase in the sliding energy barrier for the case of intercalated heterostructure as compared with the unintercalated *** sliding of the silicene encounters the maximum energy barrier of 0.14 *** analysis shows the noteworthy differences between calculated in-plane and out-of-plane part of dielectric function.A variation of the planar average charge density difference,dipole charge transfer and dipole moment have been discussed to elucidate the usability spectrum of the *** employed approach based on intercalation and layer sliding can be effectively utilized for obtaining next-generation multifunctional devices.

关键词： vdW heterostructure intercalation tuning of properties layer sliding interfacial electronic properties

无锡钢上镀铬层的晶体织构与其机械寿命的关系

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电镀与涂饰 2012年第8期31卷 1-6页

作者： O. B. Girin v. I. Ovcharenko materials Science Department Ukrainian State University of Chemical Technology

采用 X 射线衍射研究了在接近工业条件下制备的无锡钢上薄镀铬层(0.03 μm或每面 0.22 g/m2)的晶体织构特征。实验发现,铬镀层的晶体结构含以下组分:以垂直于镀层表面的[111]为轴心的轴向分量,(111)[112]受限分量以及一个自由分量。其中... 详细信息

采用 X 射线衍射研究了在接近工业条件下制备的无锡钢上薄镀铬层(0.03 μm或每面 0.22 g/m2)的晶体织构特征。实验发现,铬镀层的晶体结构含以下组分:以垂直于镀层表面的[111]为轴心的轴向分量,(111)[112]受限分量以及一个自由分量。其中[111]轴向分量为主要织构分量,是初始阶段的生长织构;(111)[112]受限分量为次要织构分量,代表了外延生长。无锡钢上镀铬层织构与亚结构的定量特征之间的规律性变化取决于沉积参数。影响无锡钢上薄镀铬层机械寿命的主要因素之一是镀层中[111]轴向织构的形成。

关键词：无锡钢铬镀层晶体织构 X射线衍射机械寿命

RANK-ligand and osteoprotegerin as biomarkers in the differentiation between periprosthetic joint infection and aseptic prosthesis loosening

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World Journal of Orthopedics 2017年第4期8卷 342-349页

作者： max J Friedrich matthias D Wimmer Jan Schmolders Andreas C Strauss milena m Ploeger Hendrik Kohlhof Dieter C Wirtz Sascha Gravius Thomas m Randau Department of Orthopedics and Trauma Surgery University Clinic of Bonn

AIm To assess serum levels of RANK-ligand(RANKL) and osteoprotegerin(OPG) as biomarkers for periprosthetic joint infection(PJI) and compare their accuracy with standard *** One hundred and twenty patients presenting with a painful total knee or hip arthroplasty with indication for surgical revision were included in this prospective clinical trial. Based on standard diagnostics(joint aspirate, microbiological, and histological samples) and musculoskeletal Infection Society consensus classification,patients were categorized into PJI, aseptic loosening,and control groups. Implant loosening was assessed radiographically and intraoperatively. Preoperative serum samples were collected and analyzed for RANKL, OPG, calcium, phosphate, alkaline phosphatase(AP), and the bone-specific subform of AP(b AP). Statistical analysis was carried out, testing for significant differences between the three groups and between stable and loose implants. RESULTS All three groups were identical in regards to age, gender, and joint distribution. No statistically significant differences in the serum concentration of RANKL(P = 0.16) and OPG(P = 0.45) were found between aseptic loosening and PJI, with a trend towards lower RANKL concentrations and higher OPG concentrations in the PJI group. The RANKL/OPG ratio was significant for the comparison between PJI and non-PJI(P = 0.005). A ratio > 60 ruled out PJI in all cases(specificity: 100%, 95%CI: 89, 11% to 100.0%) but only 30% of non-PJI patients crossed this threshold. The positive predictive value remained poor at any cut-off. In the differentiation between stable and loose implants, none of the parameters measured(calcium, phosphate, AP, and b AP) showed a significant difference, and only AP and b AP measurements showed a tendency towards higher values in the loosened group(with P = 0.09 for AP and P = 0.19 for b AP). CONCLUSION Lower RANKL and higher OPG concentrations could be detected in PJI, without statistical significance.

关键词： Aseptic loosening Diagnostic RANK-ligand Periprosthetic joint infection Biomarker Osteoprotegerin

Investigation of Li-ion transport in Li7P3S11 and solid-state lithium batteries

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Journal of Energy Chemistry 2019年第11期28卷 1-7页

作者： Chuang Yu Swapna Ganapathy Ernst R.H.van Eck Lambert van Eijck Niek de Klerk Erik m.Kelder marnix Wagemaker Department of Radiation Science and Technology Delft University of TechnologyMekelweg 152629JB Delftthe Netherlands Institute for molecules and materials Radboud University NijmegenHeyendaalseweg 1356525 AJ Nijmegenthe Netherlands

The high Li-ion conductivity of the Li7P3S11 sulfide-based solid electrolyte makes it a promising candidate for all-solid-state lithium batteries. The Li-ion transport over electrode-electrolyte and electrolyteelectrolyte interfaces, vital for the performance of solid-state batteries, is investigated by impedance spectroscopy and solid-state NmR experiments. An all-solid-state Li-ion battery is assembled with the Li7P3S11 electrolyte, nano-Li2S cathode and Li-In foil anode, showing a relatively large initial discharge capacity of 1139.5 m Ah/g at a current density of 0.064 m A/cm^ 2 retaining 850.0 m Ah/g after 30 cycles. Electrochemical impedance spectroscopy suggests that the decrease in capacity over cycling is due to the increased interfacial resistance between the electrode and the electrolyte. 1D exchange ^7Li NmR quantifies the interfacial Li-ion transport between the uncycled electrode and the electrolyte, resulting in a diffusion coefficient of 1.70(3) ×10^-14cm^2/s at 333 K and an energy barrier of 0.132 e v for the Li-ion transport between Li2S cathode and Li7P3S11 electrolyte. This indicates that the barrier for Li-ion transport over the electrode-electrolyte interface is small. However, the small diffusion coefficient for Li-ion diffusion between the Li2S and the Li7P3S11 suggests that these contact interfaces between electrode and electrolyte are relatively scarce, challenging the performance of these solid-state batteries.

关键词： Li7P3S11 Li-ion transport Spin-lattice NmR Exchange NmR Solid-state battery