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71.
Louie Leung 《电子产品世界》2006,(19):132-133,136
本文研究Altera在65nm工艺上的工程策略,介绍公司如何为客户降低生产和计划风险,并同时从根本上提高密度、性能,及降低成本和功耗.  相似文献   
72.
Highly purified allergens namely cow's milk alpha-lactalbumin (ALA). (Bos d 4), beta-lactoglobulin (BLG) (Bos d 5) and casein (Bos d 8) and goat's milk casein were prepared from the raw milk from a single animal with a known genetic background. Consequently the natural isoforms are limited, constant and characterized. Purification included selective precipitations and chromatographical steps. Characterization of structure and allergenic activity assessment of milk allergens were carried out using physicochemical and immunochemical methods. Taken together data demonstrated the absence of impurities and of contamination by other milk allergens in each preparation. NMR and circular dichroism analyses confirmed the native conformation and proper folding of ALA and BLG and the expected absence of folding of bovine and caprine casein. Enzyme immuno assays confirmed the native conformation of BLG and the purity and immunoreactivity of all the proteins. The allergenic activity, e. g. the IgE binding capacity, of purified proteins was identical as that of those proteins when present in milk. The purified proteins also demonstrated the ability to provoke the degranulation of humanized rat basophilic leukaemia cells. All the data thus confirm the purity, identity, structural conformation and functionality of the prepared milk allergens.  相似文献   
73.
Chen  Lei  Li  Xi  Ji  Hong  Leung  Victor C. M. 《Wireless Networks》2019,25(7):4133-4145
Wireless Networks - As a promising way to offset the low computation capacity of user equipments (UEs), mobile edge computing (MEC) has attracted great attention of academy and industrial recently....  相似文献   
74.
BACKGROUND: To determine the effects of anatomic site on the presentation and diagnosis of malignant peripheral nerve sheath tumors (MPNSTs) and on the treatment and outcomes of the patients, the authors initiated a study of these tumors at different sites. An earlier report described MPNSTs of the buttock and lower extremity, and the current series analyzes those presenting at intrathoracic (IT) and subdiaphragmatic (SD) paraspinal sites. METHODS: The authors reviewed data on patients with paraspinal MPNSTs who were seen at Memorial Hospital during the period 1960-1995 and for whom histologic slides were available. Various clinicopathologic parameters and their effects on patient outcomes were examined. RESULTS: Twenty-five patients with 26 tumors were evaluated. Seven tumors were IT and 19 were SD; 60% of the patients had neurofibromatosis type 1 (NF1). Most patients presented with pain, and a diagnostic delay (of 3 months to 2 years) was often noted. Mean tumor sizes for SD and IT tumors were 14.3 cm and 6.6 cm, respectively. Most MPNSTs were composed of spindle cells in fascicles. Twenty-seven percent exhibited divergent differentiation. Twenty-four tumors were high grade, and a low grade component was identified in 8 tumors. Surgical resection was attempted for 23 tumors (88%), but complete resection was achieved in only 6 cases (23%). Eighty percent of the patients died of their tumors, 2-year and 5-year survival rates were 35% and 16%, and median survival was 8.5 months. Significant prognostic factors were tumor size <5 cm, the presence of a low grade component, and complete tumor resection. CONCLUSIONS: Paraspinal MPNSTs have more aggressive behavior than peripherally located tumors, mainly because of the difficulty encountered in resecting them completely. Prognoses of patients with MPNST at this site appear to be affected by resection status, tumor size, and tumor grade.  相似文献   
75.
76.
A new selection mechanism termed global annealing selection (GAnS) is proposed for the genetic algorithm. It is proved that the GAnS genetic algorithm converges to the global optimums if and only if the parents are allowed to compete for reproduction, and that the variance of population's fitness can be used as a natural stopping criterion. Numerical simulations show that the new algorithm has stronger ability to escape from local maximum and converges more rapidly than canonical genetic algorithm.  相似文献   
77.
A study of nucleating agent effects on the selected optical and mechanical properties of a semicrystalline homoisotactic polypropylene is presented. The results showed that the type and concentration of the nucleating agents to be added, and the screw speed during the compounding process, were of vital importance. It was also noticed that the improvement in optical clarity due to the addition of the additive might not necessarily benefit the mechanical properties of injection molded articles.  相似文献   
78.
Multifunctional materials that are lightweight and thermally conductive but electrically insulating are important for modern electronics, computer, and telecommunication technologies. Here, a novel foam structure of a polymer/matrix composite filled with ceramic platelets with improved thermal conductivity is reported. Such improvement is caused by the stress‐induced alignment of thermally conductive fillers in the cell wall of the plastic foam. The foam structure is very promising for use as a lightweight electronic packaging material owing to its light weight, thermal conduction ability, electrical insulation, and good processability.

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79.
Polycarbonate (PC) nanofibers were produced using anodized aluminum oxide (AAO) template assisted nanomolding. The effects of temperature on the nanoflow were investigated. It was found that higher temperature apparently enhanced the polycarbonate nanoflow and resulted in longer nanofibers in the same duration. The surface wettabilities of the polycarbonate nanofiber coated substrates showed apparent dependency on the morphology of the surface. It was found that larger honeycomb patterns would result in higher hydrophobicity than smaller honeycomb patterns. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers  相似文献   
80.
The poly(C60-co-styrene)s prepared by radical copolymerizations of C60 and styrene in bulk were characterized by multiple-detector size-exclusion chromatographs consisting of a refractometer, a differential viscometer, and/or a right-angle laser-light scattering photometer. The multidetector systems enabled the determinations of reliable, absolute molecular weights of the copolymers. The plots of intrinsic viscosity vs. molecular weight and radius of gyration vs. molecular weight offered valuable information about the molecular architectures of the copolymers. The slopes of the plots reveal that the structure of the copolymer changes with its C60 content: the copolymer with a low C60 content of 0.58 wt% possesses a linear structure, whereas its conger with a high C60 content of 1.14 wt% possesses a branched structure.  相似文献   
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