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121.
After a thorough review of some controllable parameters, which included field investigations, cavern dimensions, explosive, rock strength etc., cut, contour, lifters and stoping holes were introduced for blasting cavern of nucleus submarine. These design were conducted using a U. Langefors and B. Kihlstrom theory. Supported by the Navy Cavern Project Foundation of China (02)  相似文献   
122.
任雁  刘佳  刘斌  王晓强 《锻压技术》2022,47(1):98-105
为了确定给定范围内的超声滚挤压风电轴承材料表面粗糙度加工参数的最优区间,以42CrMo钢风电轴承材料试样为研究对象,开展超声滚挤压表面粗糙度试验,基于试验结果构建表面粗糙度指数函数预测模型,分析加工参数对表面粗糙度及其灵敏度的影响,确定加工参数的稳定域和非稳定域,优选出最佳的超声滚挤压42CrMo钢表面粗糙度加工参数区...  相似文献   
123.
Lithium-ion batteries(LIBs) represent efficient energy storage technology that can help to alleviate fossil fuel-based CO_2 emissions.Presently,LIBs are being applied extensively in consumer electronics and electric vehicles,but because of limited resources,there is an urgent need for spent LIB recycling technologies.The complexity of LIBs,especially the electrode part,makes it difficult to achieve precision separations for each single component from the used electrode with low emissions.Herein,we propose a three-step treatment for the separation of cathode components.In detail,detaching of the current collector from the cathode is accomplished by the solvent method,which was found to be an ideal strategy compared with previous reports.Then,a thermal treatment is used to remove the polymer binder in the second step because we demonstrated that it is challenging to separate polyvinylidene fluoride(PVDF) from other cathode components by dissolution with N-methylpyrrolidone.The separation efficiency between the active material and conductive carbon by the polymer solution in the third step showed reasonably good results.We anticipate this work will serve as an important reference for the separation of each single electrode component in both laboratory-and industrialscale applications.Separation of binder and development of novel binders,which can be easily recycled for sustainable LIBs,are fruitful areas for further research.  相似文献   
124.
The neutronic properties of molten salt reactors (MSRs) differ from those of traditional solid fuel reactors owing to their nuclear fuel particularity. Based on...  相似文献   
125.
一种检测运行栈与静态数据区重叠的新方法   总被引:1,自引:0,他引:1  
嵌入式系统中由于内存限制,容易出现运行栈和数据区重叠的错误。已有的两种检测该错误的方法在准确性和易用性方面存在缺陷,不适用于基于软件模拟器的大规模回归测试。文章通过改变运行栈与静态数据区的布局,将运行栈与静态数据区重叠的错误转化为运行栈超越内存地址空间的错误。新方法大大简化了这种运行时错误的检测和调试。  相似文献   
126.
Metallurgical and Materials Transactions B - The interfacial reaction between high-Mn–high-Al steel and CaO-SiO2-type mold flux was investigated, with particular emphasis on the reduction of...  相似文献   
127.
铁路提速对轴承提出了新的极限转速要求,该义介绍了高速轴承内圈挡边磨床的研制及其达到的性能指标。基本满足了高精度滚子轴承对挡边的要求。  相似文献   
128.
Prostate cancer (PCa) is the most commonly diagnosed malignancy among men in developed countries. The five-year survival rate for men diagnosed with early-stage PCa is approximately 100%, while it is less than 30% for castration-resistant PCa (CRPC). Currently, the detection of prostate-specific antigens as biomarkers for the prognosis of CRPC is criticized because of its low accuracy, high invasiveness, and high false-positive rate. Therefore, it is important to identify new biomarkers for prediction of CRPC progression. Extracellular vesicles (EVs) derived from tumors have been highlighted as potential markers for cancer diagnosis and prognosis. Specifically, urinary EVs directly reflect changes in the pathophysiological conditions of the urogenital system because it is exposed to prostatic secretions. Thus, detecting biomarkers in urinary EVs provides a promising approach for performing an accurate and non-invasive liquid biopsy for CPRC. In this study, we effectively isolated urinary EVs with low protein impurities using size-exclusion chromatography combined with ultrafiltration. After EV isolation and characterization, we evaluated the miRNAs in urinary EVs from healthy donors and patients with CRPC. The results indicated that miRNAs (miR-21-5p, miR-574-3p, and miR-6880-5p) could be used as potential biomarkers for the prognosis of CRPC. This analysis of urinary EVs contributes to the fast and convenient prognosis of diseases, including CRPC, in the clinical setting.  相似文献   
129.
Circular RNAs (circRNAs), a class of new endogenous non-coding RNAs (ncRNAs), are closely related to the carcinogenic process and play a critical role in tumor metastasis. CircRNAs can lay the foundation for tumor metastasis via promoting tumor angiogenesis, make tumor cells gain the ability of migration and invasion by regulating epithelial-mesenchymal transition (EMT), interact with immune cells, cytokines, chemokines, and other non-cellular components in the tumor microenvironment, damage the normal immune function or escape the immunosuppressive network, and further promote cell survival and metastasis. Herein, based on the characteristics and biological functions of circRNA, we elaborated on the effect of circRNA via circRNA-associated competing endogenous RNA (ceRNA) network by acting as miRNA/isomiR sponges on tumor angiogenesis, cancer cell migration and invasion, and interaction with the tumor microenvironment (TME), then explored the potential interactions across different RNAs, and finally discussed the potential clinical value and application as a promising biomarker. These results provide a theoretical basis for the further application of metastasis-related circRNAs in cancer treatment. In summary, we briefly summarize the diverse roles of a circRNA-associated ceRNA network in cancer metastasis and the potential clinical application, especially the interaction of circRNA and miRNA/isomiR, which may complicate the RNA regulatory network and which will contribute to a novel insight into circRNA in the future.  相似文献   
130.
BOPP薄膜市场现状及发展趋势   总被引:2,自引:1,他引:1  
介绍了我国双向拉伸聚丙烯薄膜的市场现状,并对其发展趋势进行了展望。  相似文献   
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