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121.
本文以无锡某大型商场内餐饮集中区域的排油烟系统设计为依据,从餐饮区域的划分、餐饮招商过程、排油管道系统的设置、排油烟系统设备的选择及商业设施集中管理等开发商项目管理问题出发,介绍餐饮集中商业排油烟系统的设计、建设经验,以期为大型商场、商业街等饮食建筑的建设提供参考。 相似文献
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Vadim V. Ermolaev Daria M. Arkhipova Vasili A. Miluykov Anna P. Lyubina Syumbelya K. Amerhanova Natalia V. Kulik Alexandra D. Voloshina Valentine P. Ananikov 《International journal of molecular sciences》2022,23(1)
Structure–activity relationships are important for the design of biocides and sanitizers. During the spread of resistant strains of pathogenic microbes, insights into the correlation between structure and activity become especially significant. The most commonly used biocides are nitrogen-containing compounds; the phosphorus-containing ones have been studied to a lesser extent. In the present study, a broad range of sterically hindered quaternary phosphonium salts (QPSs) based on tri-tert-butylphosphine was tested for their activity against Gram-positive (Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria and fungi (Candida albicans, Trichophyton mentagrophytes var. gypseum). The cation structure was confirmed to determine their biological activity. A number of QPSs not only exhibit high activity against both Gram-positive and -negative bacteria but also possess antifungal properties. Additionally, the hemolytic and cytotoxic properties of QPSs were determined using blood and a normal liver cell line, respectively. The results show that tri-tert-butyl(n-dodecyl)phosphonium and tri-tert-butyl(n-tridecyl)phosphonium bromides exhibit both low cytotoxicity against normal human cells and high antimicrobial activity against bacteria, including methicillin-resistant strains S. aureus (MRSA). The mechanism of QPS action on microbes is discussed. Due to their high selectivity for pathogens, sterically hindered QPSs could serve as effective tunable biocides. 相似文献
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以三孢布拉氏霉为菌种,对其发酵制备的番茄红素菌体粉的经口急性毒性、遗传毒性及短期毒性等进行了研究。结果表明:番茄红素菌体粉经口最大耐受量(MTD)大于18g·kg-1,毒性分级为无毒级;Ames实验、小鼠骨髓细胞染色体畸变实验、小鼠精子畸形实验均表明番茄红素菌体粉无明显遗传毒性;30d短期喂养各组小鼠无异常症状,无死亡,其对小鼠的体重增长、血常规、血生化、脏器系数均无显著的影响。揭示了番茄红素菌体粉有较好的安全性,为番茄红素菌体粉直接应用成保健食品等提供理论依据。 相似文献
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基于气体分子红外吸收光谱的原理,设计了基于自聚焦透镜的透射式气室结构。利用自聚焦透镜作为光纤准直透镜和聚焦透镜,应用于透射型气室,并提出了在透射式气室中将多对自聚焦透镜组串联用以增加吸收光程的方法,用该方法可以明显提高气室的检测灵敏度。基于自聚焦透镜的透射式气室成功地应用于基于谐波检测技术的吸收型光纤气体传感器系统中,获得较好的检测效果。 相似文献
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中国天然气勘探开发现状及物探技术需求 总被引:4,自引:0,他引:4
2000年以来,中国石油天然气集团公司在鄂尔多斯盆地、四川盆地、塔里木盆地、松辽盆地、柴达木盆地、渤海湾盆地等的天然气勘探中不断获得新的发现,初步形成了东部、中部、西部协调发展的合理布局。现阶段面临的问题是如何尽快将资源优势转化为经济优势。目前,我国天然气主要储集层为碎屑岩、碳酸盐岩和火山岩三大岩石类型。碎屑岩储层特征表现为我国中部丘陵地区的低孔、低渗的致密砂岩以及西部复杂高陡构造的孔隙砂岩;碳酸盐岩和火山岩储层普遍埋藏较深,非均质性强,缝洞单元难以刻画。因此,必须采用有针对性的地球物理勘探技术,优先发展碎屑岩气藏检测勘探技术,强化地震岩石物理等基础研究,加快碳酸盐岩、火山岩气藏检测技术攻关。同时开展高密度、多波地震勘探等前沿技术研究,为定量评价和产能建设提供技术保障。 相似文献
127.
This paper provides a critical evaluation of Australia’s new Renewable Energy Target (RET) program with respect to its capacity to support wind power development. Four structural flaws associated with the RET which undermine its effectiveness as a catalyst for technological change in the electricity sector are discussed: (i) the inclusion of waste coal mine gas (WCMG) as an eligible fuel source which acts as an indirect coal industry subsidy, (ii) program duration which is too short and ill-structured, (iii) a multiplier that is well-intended to support small-scale renewable technologies but which creates “phantom capacity”, and (iv) the capped target of 45,000 GWh which will stymie long-term wind power market investment. The paper concludes with recommendations which stress the importance of passing effective Carbon Pollution Renewable Scheme (CPRS) legislation to offset the weaknesses associated with the RET. If an effective CPRS cannot be implemented, the paper recommends that amendments be made to the RET to (i) remove WCMG from the list of approved alternative energy sources, and (ii) extend the RET targets to reach 120,000 GWh by 2030. 相似文献
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Although landmarks are an integral part of navigation, they have rarely been used explicitly within electronic pedestrian navigation aids. We describe a two-part study into the use of landmarks in such aids, using a set of field experiments. The first part investigated whether such devices can be effective for older adults (over 60 years old), who might particularly benefit from them due to declines in sensory, cognitive and motor abilities. The second part compared the effectiveness of different methods of presenting landmark information. We show that a pedestrian navigation aid based around landmarks is particularly useful for older people and demonstrate that text, speech and photographs are all effective ways of presenting landmark information, although speech on its own has some drawbacks. We found that different people prefer information to be presented in different modalities, indicating a need for personalisation, although multi-modality may also help to address this issue. 相似文献