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71.
通过对45钢厚板断裂的宏观微观分析,认为该钢板断裂的原因为板材在铆焊气割时,加热不均匀,局部过热,冷却速度过快,产生粗大的魏氏组织,且有沿晶三次渗碳体存在,材质变脆,同时产生较大的内应力,使钢板生成微裂纹,在后来的弯卷过程中开裂. 相似文献
72.
采用X射线法测算金属材料内部残余应力的研究 总被引:4,自引:0,他引:4
阐述了采用X射线法测量经感应加热淬火后的45号钢试样内部的残余应力的原理和方法.试验表明,用X射线法测量和用修正公式计算残余应力沿层深的分布准确、可靠. 相似文献
73.
摘要:采用钢球冲击45号钢盘,观测了在不同接触条件、冲击次数及载荷条件下钢盘表面的塑性变形情况.发现在低冲击次数条件下,使用低黏度油的凹坑深度与干接触相近,但在高次数冲击条件下,冲击深度与干接触条件下相比大幅度变浅.而高黏度油条件下的凹坑深度一直最浅.在其他条件相同时,冲击深度随载荷的增加而增加.冲击时,由于凹坑中心产生的热量不断向边缘传递,使凹坑边缘形成凸起即形成所谓彩虹环.彩虹环随润滑油黏度的增加及载荷的增加而高度增加.润滑油的使用可以降低材料表面的塑性变形和磨损.对于干接触条件,凹坑内部发生微细颗粒碎化.而油润滑时凹坑内部出现微裂纹.微细颗粒碎化及微裂纹的程度均随冲击次数和载荷的增加而增加. 相似文献
74.
《The Electricity Journal》2021,34(7):107000
Carbon capture utilization and storage is an important technology option to rapidly and profoundly decarbonize the power sector, but will not deploy without substantial incentives or regulation. Assessment of U.S. policy options reveals that current incentives only partially close the finance gap and are most sensitive to fuel type and ownership structure. Recent proposed legislation would in some designs attract private investment for many projects, leading to widespread deployment of CCUS in the power sector. Additional constraints and concerns (including technology options and presence of CO2 infrastructure) could play an important secondary role. This study discusses the specific US incentive policies that can provide investors and lenders with net cash flows that are adequate to attract private capital to CCUS power projects in the US. 相似文献
75.
刘清 《湖南工业职业技术学院学报》2002,2(1):70-71
通过对调质钢与非调质钢的对比,明确说明了45钢,40Cr钢及YF40MnV钢的力学性能和应用情况。通过YF40MnV在拖拉机驱动轴及离合器轴上的替代使用,说明了新型材料的发展远景及对比教学的优越性。 相似文献
76.
Raquib Hasan Kambri Schaner Pranothi Mulinti Amanda Brooks 《International journal of molecular sciences》2021,22(14)
While the infection rate after primary total joint replacements (TJR) sits at 1–2%, for trauma-related surgery, it can be as high as 3.6 to 21.2% based on the type of trauma; the risk of reinfection after revision surgery is even higher. Current treatments with antibiotic-releasing PMMA-based bone cement/ beads and/or systemic antibiotic after surgical debridement do not provide effective treatment due to fluctuating antibiotic levels at the site of infection, leading to insufficient local antibiotic concentration. In addition, non-biodegradable PMMA does not support bone regrowth in the debrided void spaces and often must be removed in an additional surgery. Here, we report a bioactive glass or bioglass (BG) substrate-based biodegradable, easy to fabricate “press fitting” antibiotic-releasing bone void filling (ABVF-BG) putty to provide effective local antibiotic release at the site of infection along with support for bone regeneration. The ABVF-BG putty formulation had homogenously distributed BG particles, a porous structure, and showed putty-like ease of handling. Furthermore, the ABVF-BG putty demonstrated in vitro antibacterial activity for up to 6 weeks. Finally, the ABVF-BG putty was biodegradable in vivo and showed 100% bacterial eradication (as shown by bacterial cell counts) in the treatment group, which received ABVF-BG putty, compared to the infection control group, where all the rats had a high bacterial load (4.63 × 106 ± 7.9 × 105 CFU/gram bone) and sustained osteomyelitis. The ABVF-BG putty also supported bone growth in the void space as indicated by a combination of histology, µCT, and X-ray imaging. The potential for simultaneous infection treatment and bone healing using the developed BG-based ABVF-BG putty is promising as an alternative treatment option for osteomyelitis. 相似文献
77.
Hye Eun Lee Min Kyo Jung Seul Gi Noh Hye Bin Choi Se hyun Chae Jae Hyeok Lee Ji Young Mun 《International journal of molecular sciences》2021,22(21)
Iron overload in the brain, defined as excess stores of iron, is known to be associated with neurological disorders. In neurodegeneration accompanied by brain iron accumulation, we reported a specific point mutation, c.974-1G>A in WD Repeat Domain 45 (WDR45), showing iron accumulation in the brain, and autophagy defects in the fibroblasts. In this study, we investigated whether fibroblasts with mutated WDR45 accumulated iron, and other effects on cellular organelles. We first identified the main location of iron accumulation in the mutant fibroblasts and then investigated the effects of this accumulation on cellular organelles, including lipid droplets, mitochondria and lysosomes. Ultrastructure analysis using transmission electron microscopy (TEM) and confocal microscopy showed structural changes in the organelles. Increased numbers of lipid droplets, fragmented mitochondria and increased numbers of lysosomal vesicles with functional disorder due to WDR45 deficiency were observed. Based on correlative light and electron microscopy (CLEM) findings, most of the iron accumulation was noted in the lysosomal vesicles. These changes were associated with defects in autophagy and defective protein and organelle turnover. Gene expression profiling analysis also showed remarkable changes in lipid metabolism, mitochondrial function, and autophagy-related genes. These data suggested that functional and structural changes resulted in impaired lipid metabolism, mitochondrial disorder, and unbalanced autophagy fluxes, caused by iron overload. 相似文献
78.
K. Giese 《Baurechtliche Bl?tter: bbl》2008,11(4):148
Dreikammerkl?ranlagen entsprechen offenkundig nicht dem Stand der Technik. Da offenkundige Tatsachen keines Beweises bedürfen,
ist kein Sachverst?ndigengutachten erforderlich. 相似文献
79.
Genetically modified (GM) canola is the most widely grown oilseed crop in Canada. At this time, commercially produced GM canola cultivars in Canada have the events GT73/RT73 and Ms8xRf3. Commercial seed sale of canola cultivars containing the GM events such as OXY235 and T45 has been discontinued. Adventitious presence of GM seeds and grains in non-GM grains is a concern for international grain trade, and development of effective detection methods is important. A multiplex qualitative PCR procedure was established for the detection of the GM canola events OXY235, Ms8xRf3, T45 and GT73. The presence of the GM canola events was also successfully detected in ground spiked wheat and barley grain samples prepared at 0.1%, 0.5% and 1.0% levels (w/w). The GT73 real-time PCR assay was successfully used to quantify DNA extracted from spiked ground canola samples consisting of 5%, 1%, 0.5% and 0.1% GT73 (w/w). 相似文献
80.
This paper describes numerical verification of solutions of Nekrasov’s integral equation which is a mathematical model of two-dimensional water waves. This nonlinear and periodic integral equation includes a logarithmic singular kernel which is typically found in some two-dimensional potential problems. We propose the verification method using some properties of the singular integral for trigonometric polynomials and Schauder’s fixed point theorem in the periodic Sobolev space. A numerical example shows effectiveness of the present method. 相似文献