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11.
Several V-W-Ti alloys with about 50% reduction in thickness by cold rolling were isochronally annealed at temperatures from 100 to 1100 °C. Hardness was measured after the annealing. By comparison with V4Cr4Ti and V4Ti alloys, the V6WTi alloy was found to begin recovery at a temperature about 100 °C higher, while the full recrystallization temperature was around 900 °C for all of the alloys. Hardness decreased successively above 500 °C in V8W, as is the case in pure V. Impurity induced hardening was observed around 300 °C only in the alloys without Ti. Precipitation and the interaction between interstitial impurities and dislocations were supposed to be the main contributors to the different recovery and recrystallization behaviors of the alloys.  相似文献   
12.
橡塑磁条在永磁音像微特电机中的应用   总被引:1,自引:0,他引:1  
本文简述了橡塑磁条的制造工艺及在永磁音像电机规模生产中的应用,与铁氧体烧结磁环进行比较,阐述了橡塑磁条在音像微特电机中使用的优势。  相似文献   
13.
随着重型设施项目的增加。装备制造联盟企业应运而生。装备制造联盟企业的成功运作与管理需要支持其信息系统的、动态的、集成的、项目拉动的联盟企业模型。基于一般企业建模方法论与体系结构。运用面向对象、基于组件的建模方法及面向过程的分析技术。建立了装备制造项目联盟企业多视图集成的管理系统模型框架。  相似文献   
14.
Vanadium oxide thin films were grown at room temperature by direct current and radio-frequency reactive sputtering systems to compare the structural and electrochemical properties. Rutherford backscattering spectrometry and Fourier transform infrared measurements reveal that the composition of the as-deposited films consists of the V2O5 phase regardless of the deposition methods. Wide-angle X-ray diffraction measurements show that the crystallinity of the as-deposited V2O5 films is different depending on the deposition method. Films deposited by direct current reactive sputtering were amorphous, whereas films deposited by radio-frequency reactive sputtering were crystalline. Scanning electron microscopy measurements show that the V2O5 films grown by radio-frequency reactive sputtering had a large grain size but the films grown by direct current reactive sputtering were amorphous. Charge–discharge measurements taken at room temperature with a constant current clearly indicate that the films grown by direct current sputtering demonstrated typical amorphous behavior, whereas the V2O5 films grown by radio-frequency sputtering demonstrated the discharge behavior of crystalline V2O5. The origin of the structural and electrochemical properties of film grown by radio-frequency reactive sputtering is a self-bias effect. The self-bias effect induces ion bombardment during the growth of vanadium oxide thin film. These results suggest that direct current reactive sputtering is more desirable for growing amorphous V2O5 thin film than radio-frequency reactive sputtering.  相似文献   
15.
Networked Manufacturing is the trend evolution for manufacture enterprise to gain core competence in the networked economy environment. In this paper, the definition of the strategic alliance is introduced and its life cycle is described. As the selection of suitable partners is of vital importance to the success for strategic alliance in Networked Manufacturing environment, also in this paper, the definition, criteria and process for partner selection are introduced. Then the fuzzy-AHP (Analytic Hierarchy Process) method, as a fuzzy extension of analytic hierarchical approach for partner selection, is given. In the end, a case study is provided.  相似文献   
16.
针对钛合金耐磨性差、易产生氢脆的特性,以格栅状高纯度固体石墨做源极,钛合金Ti6A14V做阴极,氩气作为工作气体,依靠辉光放电和空心阴极效应在Ti6A14V表面制备渗碳合金层;X射线衍射和辉光放电光谱试验显示,合金层由高硬度相TiC及游离态减磨C相组成;渗层内C元素的含量呈梯度分布;表面硬度大幅度提高.由表及里硬度梯度降低;反复试验表明,试样周围高浓度、稳定的渗碳气氛对形成理想的渗碳效果是非常重要的.  相似文献   
17.
Microstructural changes in the surface layer of Ti-6Al-4V alloy after sliding wear in vacuum have been studied by means of scanning and transmission electron microscopy (SEM and TEM). The wear rates of Ti-6Al-4V alloy in vacuum were measured under different sliding velocities and loads. The experimental results showed that a severely deformed layer with a grain size of 50–100 nm and thickness about 70 μm was formed underneath the worn surface. Under the slower sliding velocities, the substructure of the layer had a high dislocation density, while under higher sliding velocities, twins were found to exist in the substructure. A process by which the deformed layer formed has been proposed and the deformation of materials at the contacting spots of the Ti-6Al-4V sample is discussed.  相似文献   
18.
Abstract

Co-stabilised (Y,Mg) partially stabilised zirconia (PSZ) ceramics with MgAl2O4 spinel additions were produced, with industrial zirconia as the main starting material. Powders were prepared using a mechanical milling–mixing process. The effect of the annealing process on the mechanical properties, phase compositions, and microstructure of fine grained PSZ ceramics was investigated.  相似文献   
19.
Factor V deficiency, an ultra-rare congenital coagulopathy, is characterized by bleeding episodes that may be more or less intense as a function of the levels of coagulation factor activity present in plasma. Fresh-frozen plasma, often used to treat patients with factor V deficiency, is a scarcely effective palliative therapy with no specificity to the disease. CRISPR/Cas9-mediated gene editing, following precise deletion by non-homologous end-joining, has proven to be highly effective for modeling on a HepG2 cell line a mutation similar to the one detected in the factor V-deficient patient analyzed in this study, thus simulating the pathological phenotype. Additional CRISPR/Cas9-driven non-homologous end-joining precision deletion steps allowed correction of 41% of the factor V gene mutated cells, giving rise to a newly developed functional protein. Taking into account the plasma concentrations corresponding to the different levels of severity of factor V deficiency, it may be argued that the correction achieved in this study could, in ideal conditions, be sufficient to turn a severe phenotype into a mild or asymptomatic one.  相似文献   
20.
We report the first Polish representative of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA), lukS/F-PV-positive, encoding the ermB gene, as a genetic determinant of constitutive resistance to macrolides, lincosamides, and streptogramin B antibiotics, cMLS-B. This is the first detection of the CA-MRSA strain responsible for nosocomial infection in the Warsaw Clinical Hospital. Resistance to β-lactams associates with a composite genetic element, SCCmec cassette type VT (5C2&5). We assigned the strain to sequence type ST338 (single-locus variant of ST59), clonal complex CC59, spa-type t437, and agr-type I. Genomic-based comparison was designated SO574/12 as an international Taiwan clone, which has been so far described mainly in the Asia-Pacific region. The ermB gene locates on the chromosome within the 14,690 bp mobile element structure, i.e., the MESPM1-like structure, which also encodes aminoglycoside- and streptothricin-resistance genes. The MESPM1-like structure is a composite transposon containing Tn551, flanked by direct repeats of IS1216V insertion sequences, which probably originates from Enterococcus. The ermB is preceded by the 273 bp regulatory region that contains the regulatory 84 bp ermBL ORF, encoding the 27 amino acid leader peptides. The latest research suggests that a new leader peptide, ermBL2, also exists in the ermB regulatory region. Therefore, the detailed function of ermBL2 requires further investigations.  相似文献   
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