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111.
Metal Science and Heat Treatment - A facility for physical simulation is used to plot dependences of flow stress on the degree of deformation in the temperature range from 1000 to 1230°C at...  相似文献   
112.
A comparative study of propylene polymerization in liquid monomer is performed under laboratory conditions using the IK-8-21 Ti-Mg catalyst designed at the Boreskov Institute of Catalysis and imported industrial catalysts (conditionally labeled TMC-1, -2, and -3). The activity and stereospecificity of the catalysts are estimated along with properties of the resulting polypropylene (granular composition and physicomechanical characteristics). It is shown that the IK-8-21 catalyst is not inferior to imported counterparts in terms of catalytic properties in the synthesis of polypropylene. The polypropylene powder formed on IK-8-21 is homogeneous and has good morphology. The physicomechanical characteristics of polypropylene synthesized on the domestic IK-8-21 catalyst are similar to those for polypropylene prepared with the imported TMK-1 catalyst.  相似文献   
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JOM - The use of titanium machine turnings has been identified as a possible ultralow-cost method to produce titanium powder. However, very little data are available on the viability of this...  相似文献   
116.
Protection of Metals and Physical Chemistry of Surfaces - The methods of describing absolute adsorption isotherms of binary nonelectrolyte solutions components on macro- and microporous adsorbents...  相似文献   
117.
Protection of Metals and Physical Chemistry of Surfaces - A method for introducing small amounts of betulin (up to 1 wt %) into a mesoporous carbon material with a preset specific surface area of...  相似文献   
118.
Protection of Metals and Physical Chemistry of Surfaces - In the present work, a method for producing new shaped composite materials by introducing a metal-organic framework structure Cu-BTC110...  相似文献   
119.
Solar radiation and insufficient shading on buildings during peak hours might increase outdoor insolation and indoor energy needs for cooling loads. Overhang device systems were designed to block subtropical solar radiation. Passive shading strategies help to decrease outdoor insolation, delaying the transfer of heat to the inside of the building and reducing the energy needs for meeting cooling loads. Eight computational 3D models of a building in Taipei City, one set in a base case scenario and the others in the application of seven overhang device systems, were examined by performing outdoor and indoor simulations. Results show that combined overhang device-single edge and layer (OD-SEL) system had the highest capacity for blocking total solar radiation during peak hours. Effectiveness was most significant on the 18th floor and gradually reduced as it approached the ground level. It was demonstrated that shading projected by OD systems on the outdoor areas of the building can lead to mitigation of the urban heat island (UHI) phenomenon by decreasing the outdoor insolation ratings. Shade gained by use of OD systems on the outdoor areas and the envelope of the building can reduce the insolation ratings on the envelope, delaying the transfer of heat into the building. Gaining shade by using OD-SEL systems on the rooftop, walls and windows was the most effective passive strategy for removing indoor overheating, reducing the need for cooling loads. The savings achieved on cooling loads are representing energy savings for the air conditioning system.  相似文献   
120.
Osteosarcoma represents a rare cause of cancer in the general population, accounting for <1% of malignant neoplasms globally. Nonetheless, it represents the main cause of malignant bone neoplasm in children, adolescents and young adults under 20 years of age. It also presents another peak of incidence in people over 50 years of age and is associated with rheumatic diseases. Numerous environmental risk factors, such as bone diseases, genetics and a history of previous neoplasms, have been widely described in the literature, which allows monitoring a certain group of patients. Diagnosis requires numerous imaging tests that make it possible to stratify both the local involvement of the disease and its distant spread, which ominously determines the prognosis. Thanks to various clinical trials, the usefulness of different chemotherapy regimens, radiotherapy and surgical techniques with radical intent has now been demonstrated; these represent improvements in both prognosis and therapeutic approaches. Osteosarcoma patients should be evaluated in reference centres by multidisciplinary committees with extensive experience in proper management. Although numerous genetic and rheumatological diseases and risk factors have been described, the use of serological, genetic or other biomarkers has been limited in clinical practice compared to other neoplasms. This limits both the initial follow-up of these patients and screening in populations at risk. In addition, we cannot forget that the diagnosis is mainly based on the direct biopsy of the lesion and imaging tests, which illustrates the need to study new diagnostic alternatives. Therefore, the purpose of this study is to review the natural history of the disease and describe the main biomarkers, explaining their clinical uses, prognosis and limitations.  相似文献   
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