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81.
随着计算机技术的不断发展,越来越多的企业开始对各类管理信息系统进行整合.数据层面的集成是信息整合整体架构的重要组成部分.本文总结了异构数据整合系统的关键点,并具体针对IBM DB2 II V.8.1的信息整合器进行了原理、技术实现等方面的分析.同时根据具体的开发实践介绍了该技术在数字校园异构数据整合系统建设中的应用.  相似文献   
82.
针对现有微囊藻毒素(MC-LR)检测方法操作复杂、因标记而污染环境、仪器贵重,不利于现场快速检测等问题,将自行研制的表面等离子体共振(SPR)生物芯片检测仪应用于微囊藻毒素的检测,提出抑制型SPR生物芯片快速检测痕量微囊藻毒素的方法。采用该方法分别对浓度为3.5、2.5、1.5、1、0μg/L的MC-LR样品进行了检测。结果表明:该方法检测限小于1μg/L,可满足世界卫生组织(WHO)对于饮用水和我国地表水环境质量标准中MC-LR最低含量检测的需求。该方法完成一个样品检测耗时约8 min,相比于高效液相色谱法(HPLC)和酶联免疫吸附法(ELISA)等传统检测方法,快速定量是其最大的优势,可用于食品质量监控和现场实时检测。   相似文献   
83.
基于离子-分子共存理论建立了计算电渣重熔Inconel 718高温合金过程中平衡Al和Ti含量的热力学模型.并讨论了Ca O-Si O2-MgO-Fe O-Al2O3-Ti O2-Ca F2电渣重熔渣系成分变化时, 渣中各组元的活度、活度比值与炉渣成分的关系.与此同时, 研究了不同温度条件下, 镍基合金中平衡的Al和Ti含量与炉渣成分之间的关系.结果表明:冶炼温度升高时, 合金中平衡的Al含量随之升高, 而平衡Ti含量降低;渣中MgO和Ca F2只起到调整炉渣物理化学性质的作用, 对控制镍基合金中Al和Ti元素烧损作用不大.  相似文献   
84.
建筑学毕业设计教学的思考   总被引:1,自引:0,他引:1  
肖大威  黄翼  许吉航 《华中建筑》2006,24(5):135-138
该文针对建筑学专业毕业设计的教学目标,提出了一套行之有效的毕业设计教学过程及其操作步骤,讨论了教学毕业设计的思维方法,并阐述了毕业设计创作中的基本理论与创新模式.  相似文献   
85.
肖立春  徐燕征 《华中建筑》2006,24(12):45-47
基本几何体在建筑的形体塑造中一直处于主导地位.基本几何形体在现代美学与社会条件的综合作用下走向前台并逐渐占据主导地位,又在人文与现代科学的否定扣冲压下,编辑方式不断发生受化论文从几个侧面论述了变化的原固和发展趋向。  相似文献   
86.
系统地研究了粉末聚酯(PET)固相缩聚,得到了有效的干燥结晶条件:140℃干燥120 min,180℃再结晶45 min,切片含水率低于30μg/g;研究了反应温度,粉末粒径和N2流量对PET固相缩聚的影响,分析粉末固相缩聚存在N2流量阈值的机理。结果表明:反应温度越高,颗粒越小,固相缩聚反应速度越快;粉末 PET预聚体在一定温度下固相缩聚,存在N2流量阈值。在此流量下,达到该温度下的该粒径粉末的最大界面扩散速率和固相缩聚的最大反应速度。相同反应温度下,粉末粒径越小,阈值N2流量越大。  相似文献   
87.
In this study, corrosion behaviour of double-phase Al1.3CrFeNi chemically complex alloy was investigated, including hot corrosion and electrochemical corrosion. Hot corrosion behaviour of Al1.3CrFeNi alloy was explored in molten 75 wt-% Na2SO4?+?25 wt-% NaCl salt. The result revealed that the corrosion kinetic curve of Al1.3CrFeNi alloy followed the exponential rate rule through mass loss measurement. In addition, it prevented that the formed corrosion layer had obvious stratification including external granular Al2O3 and inner porous Cr2O3 when corrosion time was up to 100?h. Besides, it should be noted that the Al1.3CrFeNi alloy was sensitive to the molten salt containing chlorine, which makes the alloy surface leave voids and bring about acceleration of corrosion. Meanwhile, electrochemical corrosion resistance of Al1.3CrFeNi alloy in NaCl solution with different concentrations (0.6, 1.0 and 2.0?mol?L?1) was investigated at room temperature. The results revealed that Al1.3CrFeNi alloy showed superior corrosion resistance in NaCl solution due to the existence of Al and Cr which aid the formation of protective oxide layer.  相似文献   
88.
The recycling and reuse of biomass waste for the preparation of carbon-based adsorbents is a sustainable development strategy that has a positive environmental impact. It is well known that a large amount of silk sericin (SS) is dissolved in the wastewater from the silk industry. Utilizing the SS instead of discharging it into the environment without further treatment would reduce environmental and ecological problems. However, effective enrichment of the SS from the aqueous solution is a challenge. Here, with the help of carboxymethyl chitosan (CMCS), which can form a gel structure under low voltage, an SS/CMCS hydrogel with SS as the major component was prepared via electrodeposition at a 3 V direct-current (DC) voltage for five minutes. Following a carbonization process, an SS-based adsorbent with good performance for the removal of methylene blue (MB) from an aqueous solution was prepared. Our results reveal that the SS/CMCS hydrogel maintains a porous architecture before and after carbonization. Such structure provides abundant adsorption sites facilitating the adsorption of MB molecules, with a maximum adsorptive capacity of 231.79 mg/g. In addition, it suggests that the adsorption is an exothermic process, has a good fit with the Langmuir model, and follows the intra-particle diffusion model. The presented work provides an economical and feasible path for the treatment of wastewater from dyeing and printing.  相似文献   
89.
Good sleep quality is essential for maintaining the body’s attention during wakefulness, which is easily affected by external factors such as an ambient temperature. However, the mechanism by which an ambient temperature influences sleep–wake behaviors remains unclear. The dorsomedial hypothalamus (DMH) has been reported to be involved in thermoregulation. It also receives projection from the preoptic area, which is an important region for sleep and energy homeostasis and the suprachiasmatic nucleus—a main control area of the clock rhythm. Therefore, we hypothesized that the DMH plays an important role in the regulation of sleep related to ambient temperatures. In this study, we found that cold exposure (24/20/16/12 °C) increased wakefulness and decreased non–rapid eye movement (NREM) sleep, while warm exposure (32/36/40/44 °C) increased NREM sleep and decreased wakefulness compared to 28 °C conditions in wild-type mice. Then, using non-specific and specific apoptosis, we found that lesions of whole DMH neurons and DMH γ–aminobutyric acid (GABA)-ergic neurons induced by caspase-3 virus aggravated the fluctuation of core body temperature after warm exposure and attenuated the change in sleep–wake behaviors during cold and warm exposure. However, chemogenetic activation or inhibition of DMH GABAergic neurons did not affect the sleep–wake cycle. Collectively, our findings reveal an essential role of DMH GABAergic neurons in the regulation of sleep–wake behaviors elicited by a change in ambient temperature.  相似文献   
90.
Pannexins (PANX) were cloned based on their sequence homology to innexins (Inx), invertebrate gap junction proteins. Although there is no sequence homology between PANX and connexins (Cx), these proteins exhibit similar configurations. The PANX family has three members, PANX1, PANX2 and PANX3. Among them, PANX1 has been the most extensively studied. The PANX1 channels are activated by many factors, including high extracellular K+ ([K+]e), high intracellular Ca2+ ([Ca2+]i), Src family kinase (SFK)-mediated phosphorylation, caspase cleavage and mechanical stimuli. However, the mechanisms mediating this mechanosensitivity of PANX1 remain unknown. Both force-from-lipids and force-from-filaments models are proposed to explain the gating mechanisms of PANX1 channel mechanosensitivity. Finally, both the physiological and pathological roles of mechanosensitive PANX1 are discussed.  相似文献   
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