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81.
Railway Engineering Science - Sorting humps are the main technical means providing the breaking- and making-up of freight trains. Automation of sorting process by implementing microprocessor...  相似文献   
82.
A ternary orthorhombic phase (Pbma, a = 2.34, b = 1.62 and c = 2.00 nm) was revealed around the Al77Rh15Ru8 composition. It is structurally related to the Al-Rh and Al-Pd ?-phases.  相似文献   
83.
Powder Metallurgy and Metal Ceramics - The nature of phase equilibria has been examined for the first time in the Al–Ti–Pt system in the range 0–50 at.% Pt at subsolidus...  相似文献   
84.
By dint of the aging population and further deepened with the Covid-19 pandemic, lung disease has turned out to be a major cause of worldwide morbidity and mortality. The condition is exacerbated when the immune system further attacks the healthy, rather than the diseased, tissue within the lung. Governed by unremittingly proliferating mesenchymal cells and increased collagen deposition, if inflammation persists, as frequently occurs in aging lungs, the tissue develops tumors and/or turns into scars (fibrosis), with limited regenerative capacity and organ failure. Fas ligand (FasL, a ligand of the Fas cell death receptor) is a key factor in the regulation of these processes. FasL is primarily found in two forms: full length (membrane, or mFasL) and cleaved (soluble, or sFasL). We and others found that T-cells expressing the mFasL retain autoimmune surveillance that controls mesenchymal, as well as tumor cell accumulation following an inflammatory response. However, mesenchymal cells from fibrotic lungs, tumor cells, or cells from immune-privileged sites, resist FasL+ T-cell-induced cell death. The mechanisms involved are a counterattack of immune cells by FasL, by releasing a soluble form of FasL that competes with the membrane version, and inhibits their cell death, promoting cell survival. This review focuses on understanding the previously unrecognized role of FasL, and in particular its soluble form, sFasL, in the serum of aged subjects, and its association with the evolution of lung disease, paving the way to new methods of diagnosis and treatment.  相似文献   
85.
86.
Dmytro Buchnea 《Lipids》1974,9(1):55-57
Chromatography on silicic acid-boric acid columns permits detritylation of ester lipids, essentially without acyl migration, and simultaneous separation of the reaction products. Described is the preparation of the column and its application for the synthesis of diacyl-sn-glycerols and 2-acyl-1,2-propaneiols. Presented in part at the Canadian Federation of Biological Societies Annual Meeting in Toronto, June 1971.  相似文献   
87.
Solving mobile manipulation tasks in inaccessible and dangerous environments is an important application of robots to support humans. Example domains are construction and maintenance of manned and unmanned stations on the moon and other planets. Suitable platforms require flexible and robust hardware, a locomotion approach that allows for navigating a wide variety of terrains, dexterous manipulation capabilities, and respective user interfaces. We present the CENTAURO system which has been designed for these requirements and consists of the Centauro robot and a set of advanced operator interfaces with complementary strength enabling the system to solve a wide range of realistic mobile manipulation tasks. The robot possesses a centaur‐like body plan and is driven by torque‐controlled compliant actuators. Four articulated legs ending in steerable wheels allow for omnidirectional driving as well as for making steps. An anthropomorphic upper body with two arms ending in five‐finger hands enables human‐like manipulation. The robot perceives its environment through a suite of multimodal sensors. The resulting platform complexity goes beyond the complexity of most known systems which puts the focus on a suitable operator interface. An operator can control the robot through a telepresence suit, which allows for flexibly solving a large variety of mobile manipulation tasks. Locomotion and manipulation functionalities on different levels of autonomy support the operation. The proposed user interfaces enable solving a wide variety of tasks without previous task‐specific training. The integrated system is evaluated in numerous teleoperated experiments that are described along with lessons learned.  相似文献   
88.
Dmytro Buchnea 《Lipids》1971,6(10):734-739
Procedures have been developed for the synthesis of both enantiomeric forms of mixed fatty acid, saturated and polyunsaturated 1,2-diacyl-sn-glycerols and 2,3-diacyl-sn-glycerols from D-mannitol as starting material. The following diacyl-sn-glycerols have been synthesized: 1-Stearoyl-2-linoleoyl-sn-glycerol, 1-stearoyl-2-linolenoyl-sn-glycerol, 2-linoleoyl-3-stearoyl-sn-glycerol and 2-linolenoyl-3-oleoyl-sn-glycerol. Their specific rotations, refractive indices, densities, solubilities, carbon and hydrogen analysis and iodine values have been reported. Presented in part at the ISF-AOCS World Congress, Chicago, September 1970.  相似文献   
89.
为了解决长时数据存储的难题,开展了以数字格式在蓝宝石光盘表面写入数据的研究工作。根据艾林方程,分析了利用常用无机材料进行数据存储的数据失效时间。描述了在蓝宝石材料为基底的光盘上以数字格式记录数据的基本工艺流程,重点介绍了用于蓝宝石光盘的离子束刻蚀系统。实验结果显示,蓝宝石光盘表面刻蚀的信息坑宽度为0.6μm,深度为0.2μm,磁道节距为1.6μm,符合ISO/IEC 10149:1995规定的CD-ROM格式数据存储要求,表明采用本文提出的方法实现蓝宝石光盘的数字化数据存储是可行的。此外,这种基本工艺流程不仅适用于蓝宝石光盘,同样适用于其它以高度稳定的材料(如石英玻璃)作为基底的光盘。  相似文献   
90.
The Al–Ni–Cr phase diagram was specified at 1000 °C and partially at 900 °C. The results concerning the region below 60 at.% Al agreed qualitatively with the literature data. The binary Al–Cr phases μ and γ dissolve up to 1 and 3 at.% Ni, respectively, and Al3Ni2 up to 2.5 at.% Cr. Two ternary phases were revealed: hexagonal ζ (a ≈ 1.77, c ≈ 1.24 nm) in a wide range between Al81Ni3Cr16, Al76.5Ni3Cr20.5, Al76.5Ni9Cr14.5 and Al71.5Ni9Cr19.5, and high-temperature orthorhombic (a ≈ 1.26, b ≈ 3.48, c ≈ 2.02 nm) around Al76.5Ni2.0Cr21.5.  相似文献   
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