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21.
为提高在采样环境中Bernaille等的早识别技术对BT(BitTorrent)流量识别的准确性,通过分析BT协议和BT实际传输数据,找出其中BT传输过程前期有效载荷低于70个字节的小包出现的规律,并以此为基础来识别BT流量。实验表明,对比早识别技术,该方法能够提高在采样环境中识别的准确性,克服了早识别技术对BT流中前几个数据包的依赖的不足。  相似文献   
22.
蔡文娟  李威  许娟 《微计算机信息》2006,22(29):221-222
在医疗器械领域里,电疗器械有了较大的发展,但目前电疗治疗仪的一些不足之处使其很难得到推广使用。本论文介绍了目前电疗治疗仪现状与不足,据此研制了一种新型便携式智能电疗仪。该电疗仪采用电疗的机理,选用Philips公司的低功耗的P89LPC935单片机为控制核心,具有键盘扫描、数据显示和频率强度不断变化脉冲波形输出等功能。通过便携式智能电疗治疗仪的设计,探索出一条研制便携式智能医疗器械的思路,为开发其它理疗器械提供设计参考。  相似文献   
23.
Light emission from carbon-based materials (fine grain graphite, CFC and silicon doped CFC) was observed during ITER relevant thermal shock loads by means of in situ optical diagnostics. The light emission which corresponds to particle release clearly indicated different particle release processes in the three materials. The differences were also found in the initiation temperatures of particle release and the surface morphology of the loaded areas. These results are related to the thermal stress in bulk materials. In addition to particle release, vapor cloud formation caused by thermal shock loads were observed as CII lines and lines from the C2 Swan system. No Si lines but lines from SiC2 molecules (Merrill-Sanford bands) were observed in Si doped CFC. This indicates that atomic silicon is not released under ITER relevant thermal shock loads.  相似文献   
24.
钢管混凝土柱框支剪力墙结构应用的设计探讨   总被引:1,自引:0,他引:1  
钢管混凝土柱是一种具有承载力高、抗震性能好等突出优点的结构构件,但在高层建筑框支剪力墙结构中的应用尚属开始阶段.本丈对框支剪力墙在采用钢管混凝土框支柱和钢筋混凝土框支柱的情况下,分别比较其对框支剪力墙结构的受力性能影响.通过分析比较得出:其内力变化规律仍然基本符合传统框支剪力墙的受力概念.因此,对现行规范有关框支剪力墙结构的构造规定进行局部调整后.可适宜采用钢管混凝土柱的框支剪力墙结构.本文还提出了一种受力明确、设计合理的节点形式及其设计,解决了钢管混凝土柱在高层建筑框支剪力墙结构中应用的关键问题.  相似文献   
25.
Liquid-solid reaction under irradiation (LiSoR) experiments are aimed at understanding the effects of liquid lead-bismuth eutectic (LBE) corrosion and embrittlement under irradiation on structural materials, which is one of the key items of the materials R&D for the future accelerator-driven system (ADS). The LiSoR setup is basically a LBE loop with a test section irradiated with 72 MeV protons. The second irradiation was conducted for about 34 h and terminated after a leakage of LBE was detected. Post-irradiation examinations (PIE) are being performed on both the tube and tensile specimen in the test section. Optical microscopy, scanning electron microscopy, transmission electron microscopy and microhardness tests have been completed. The results show that a crack formed in the irradiation zone of the tube. In the material in the irradiation zones of both the tube and the tensile specimen dislocation cell structure is well developed, which indicates heavy deformation due to thermal fatigue. The crack should start at the inner surface and propagate to the outer surface. The fracture surfaces of the crack are dominated by a brittle cleavage fracture mode. However, on the surfaces of the tensile specimen, no microcracks are observed.  相似文献   
26.
27.
介绍用电位滴定法测定重过磷酸钙中游离P2O5含量的方法。采用设定终点滴定,终点pH值为4.5,开始条件设置滴定前搅拌60s,最大滴定速度0.01mL/min,最小滴定速度0.005mL/min,终点前动态范围pH1.000,终点停止漂移0.02mL/min,测量点时间间隔2.0s,滴定方向选择pH值升高的方向,停止体积为成品重钙10.00mL、鲜钙20.00mL。该方法简便,快速,准确度、精密度高。  相似文献   
28.
The adenosine 5′-triphosphate-gated P2X4 receptor channel is a promising target in neuroinflammatory disorders, but the ability to effectively target these receptors in models of neuroinflammation has presented a constant challenge. As such, the exact role of P2X4 receptors and their cell signalling mechanisms in human physiology and pathophysiology still requires further elucidation. To this end, research into the molecular mechanisms of P2X4 receptor activation, modulation, and inhibition has continued to gain momentum in an attempt to further describe the role of P2X4 receptors in neuroinflammation and other disease settings. Here we provide an overview of the current understanding of the P2X4 receptor, including its expression and function in cells involved in neuroinflammatory signalling. We discuss the pharmacology of P2X4 receptors and provide an overview of P2X4-targeting molecules, including agonists, positive allosteric modulators, and antagonists. Finally, we discuss the use of P2X4 receptor modulators and antagonists in models of neuroinflammatory cell signalling and disease.  相似文献   
29.
采用原位乳液聚合方法制备了基于共价键结合的P(MMA-AN)/TiO2复合粒子,红外光谱和热失重分析结果表明P(MMA-AN)在TiO2表面接枝率为15.9%。以甲基橙溶液为目标污染物,研究了P(MMA-AN)/TiO2复合粒子和TiO2对甲基橙的吸附和光催化降解甲基橙溶液的性能,结果表明:两种粒子对甲基橙的吸附都很少;在相同时间内,P(MMA-AN)/TiO2复合粒子对甲基橙溶液的降解性能优于TiO2,紫外光照180 min后,P(MMA-AN)/TiO2复合粒子对甲基橙溶液的降解率达到了88%,而TiO2仅为74%。  相似文献   
30.
P2X7R-NLRP3 and AIM2 inflammasomes activate caspase-1 and the release of cytokines involved in viral-related liver disease. Little is known about their role in non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steato-hepatitis (NASH). We characterized the role of inflammasomes in NAFLD, NASH, and HCV. Gene expression and subcellular localization of P2X7R/P2X4R-NLRP3 and AIM2 inflammasome components were examined in histopathological preparations of 46 patients with biopsy-proven viral and metabolic liver disease using real-time PCR and immunofluorescence. P2X7R, P2X4R, and Caspase-1 are two- to five-fold more expressed in patients with NAFLD/NASH associated with chronic HCV infection than those with metabolic damage only (p ≤ 0.01 for all comparisons). The AIM2 inflammasome is 4.4 times more expressed in patients with chronic HCV infection, regardless of coexistent metabolic abnormalities (p = 0.0006). IL-2, a cytokine playing a pivotal role during chronic HCV infection, showed a similar expression in HCV and NASH patients (p = 0.77) but was virtually absent in NAFLD. The P2X7R-NLRP3 complex prevailed in infiltrating macrophages, while AIM2 was localized in Kupffer cells. Caspase-1 expression correlated with elastography-based liver fibrosis (r = 0.35, p = 0.02), whereas P2X7R, P2X4R, NRLP3, Caspase-1, and IL-2 expression correlated with circulating markers of disease severity. P2X7R and P2X4R play a major role in liver inflammation accompanying chronic HCV infection, especially when combined with metabolic damage, while AIM2 is specifically expressed in chronic viral hepatitis. We describe for the first time the hepatic expression of IL-2 in NASH, so far considered a peculiarity of HCV-related liver damage.  相似文献   
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