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排序方式: 共有1304条查询结果,搜索用时 312 毫秒
1.
徐应锦  王冬 《室内设计》2019,(2):95-100
长春洞是巍宝山保存最完整的宫 观,虽占地不到两亩①,却在有限的空间中 创造出九楼十院的空间格局。本文以长春洞 空间布局序列为研究对象,从知觉体验的 连续性入手,提出了空间变化对参观者情感 的影响,论述了在建筑空间布局序列中参观 者知觉体验逐层递进的控制机制,探讨了以 “起、承、转、合”为结构,以“知觉体验”为 章法的动态空间布局设计手法,希望为道教 建筑空间与其他超越日常的精神空间的研 究提供启示。  相似文献   
2.
Lanthanum zirconate is a promising thermal barrier coating material owing to its excellent thermophysical properties and La plays the key role in its corrosion resistance. Here, an amorphous precursor is used as raw feedstock material so as to synthesize lanthanum zirconate coatings with tailorable composition by atmospheric plasma spray (APS). Three lanthanum zirconate coatings of La1.7Zr2.3O7.15, La2.0Zr2.0O7.0 and La2.3Zr1.7O6.85 are fabricated. Furthermore, the corrosion resistance of the as-sprayed coatings against CaO-MgO-Al2O3-SiO2 at 1250℃ is investigated. The increased La content promotes the formation of a sealing layer of the crystalline Ca2La8(SiO4)6O2 apatite, which slows down the penetration of molten CaO-MgO-Al2O3-SiO2. Therefore, the infiltration rate of the La2.3Zr1.7O6.85 coating decreased up to 42.6 % compared with the other two coatings. This work develops a feasible preparation strategy to control the La composition for the improved corrosion resistance, which is expected to guide the future coating design and synthesis for the materials with big composition changes during the APS process.  相似文献   
3.
Determining and reducing the measurement uncertainty of LNG energy transfer in custody transfer operations is considered extremely important and challenging for industry. The European Metrology Research Programme (EMRP) for Liquefied Natural Gas (LNG) has been focused on reducing the uncertainty in the evaluation of LNG energy transfers by improving existing measurement methods, validating new measurement methods and development of new traceable calibration systems. Part of this project was to produce realistic measurement uncertainty budgets and to determine the sensitivity of the overall LNG energy transfer uncertainty to changes in the composition and temperature of different LNG cargoes.This paper provides details on the development of an uncertainty budget and the results from the sensitivity study. It was found that the uncertainty in the LNG energy transfer ranged from 0.56% to 0.77% when using the uncertainty budget for 461 LNG cargoes. The variation was mainly due to the difference in the LNG composition and its associated uncertainty.  相似文献   
4.
本文从配方角度,探讨在玻璃配方设计与调整中,组分对表面张力和配合料熔化进程的影响。  相似文献   
5.
内在的地方──对镇海海防历史纪念馆设计创作的思考   总被引:2,自引:0,他引:2  
从我们在招宝山顶画出第一张草图到现在,已有近三年的时间了。这期间,空间和实体的形象在我们的脑中由模糊而清晰,由笼统而具体,最后贯彻在施工的细部中。现在它已接近完成了。这是一座地方自己筹资建设的纪念馆。这是一个从地方的形象记忆和潜在精神中产生的建筑。它是对地方的纪念。镇海,位于浙江省东端丽江出海口,蚊门虎距,重关天设,自古为两浙咽喉,兵家必争之地。自明代以来,我国东南沿海屡次遭受外族侵犯,镇海口遂成为抗击外来侵略的海防重镇。直至近代的抗日战争,在这里进行的大小战役达46次之多。我国历史上著名的民族英…  相似文献   
6.
Sources of Cd,Cu, Pb and Zn in biowaste   总被引:5,自引:0,他引:5  
Biowaste, the separately collected organic fraction of municipal solid waste, can be reused for soil conditioning after composting. In this way, environmentally harmful waste management strategies, such as landfilling or incineration, can be reduced. However, frequent application of composts to soil systems may lead to the accumulation of heavy metals in soils, and therefore legal criteria were laid down in a decree to guarantee the safe use of composts. The heavy metal content of biowaste-composts frequently exceeds the legal standards, and thus raises a conflict between two governmental policies: the recycling of solid waste on the one hand, and the protection of natural ecosystems and public health on the other hand. In this study, the heavy metal content (Cd, Cu, Pb and Zn) of biowaste was compared with the natural background content of Cd, Cu, Pb and Zn in the different constituents of biowaste. For this, the physical entities of biowaste were physically fractionated by wet-sieving and subsequent water-elutriation. In this way, organic and inorganic fractions of different particle sizes were obtained and the content of Cd, Cu, Pb and Zn and the organic matter content of the different fractions were determined. On the basis of particle size, density and visual appearance, the particle-size fractions were assigned to various indoor and outdoor origins of the biowaste. It was found that a large amount of biowaste was not organic, but over 50% was made up of soil minerals due to the collection of biowaste constituents from gardens. The heavy metal content of the various fractions in biowaste was compared with the natural background contents of heavy metals in the constituents of biowaste, i.e. food products, plant material, soil organic matter and soil minerals, by collecting literature data. The heavy metal content in the fractionated physical entities of biowaste corresponded with the natural background concentration of its constituents and indicated that biowaste was not contaminated by other sources. However, the natural background content of biowaste constituents will result in heavy metal contents for biowaste-compost that will exceed the legal standards. It is advised that the legal standards for composts should be critically re-examined. The protection of soil systems could be better guaranteed if the input of heavy metals was evaluated for all inputs of fertilisers and soil conditioners, i.e. animal manures, various types of compost and artificial fertilisers.  相似文献   
7.
Ninety-six urban surface dust samples collected from Guangzhou, a typical urban center in South China, were analyzed for 16 PAHs (2-6 rings). ∑ PAHs concentrations in the urban surface dust ranged from 0.84 to 12.3 μg/g with a mean of 4.80 μg/g. High molecular weight compounds (4-6 rings) contributed to 62 to 94% of ∑ PAHs mass in the surface dust samples. Four hotspots with highest ∑ PAHs were identified via kriging prediction mapping, representing the highly-urbanized regions: central downtown, highway and industrial area. Two major origins of PAHs inputs to urban surface dust were identified as vehicle emissions (51.9%) and coal combustion (26.8%). The 95% UCL of Incremental Lifetime Cancer Risk (ILCR) due to human exposure to urban surface dust PAHs in central South China was 3.03 × 10−6 for children and 2.92 × 10−6 for adults.  相似文献   
8.
刘晓雯 《火工品》2016,(4):58-60
目前,烟花药粉的称重混合工序主要以手工操作为主,是长期制约烟花爆竹安全生产的高危工序。针对这一工序,研发了一种专门用于烟花爆竹各配料称重、混合,并保证一定的称重精度及混合均匀度的混合称重机。基于粉体混合的定量计算及分析法,得出了混合度随时间变化的曲线,确定了粉体最佳的混合时间,并验算了药粉主要成分在混合前后的最大比例误差,结果完全满足烟花生产要求。  相似文献   
9.
闵晶  卢永毅 《时代建筑》2013,(6):118-123
“空间”是中国现代建筑中一个非常重要的话语.从“空间构图”这个开启中国现代建筑“空间”话语的关键词入手,文章试图展现“空间”概念怎么与“布杂”体系的构图原理相结合,目的在于呈现“空间”概念是如何对中国现代建筑产生影响的.  相似文献   
10.
In recent years, the demand for gradient porous ceramics is increasing in engineering field. By traditional process, the disadvantage of prepared gradient porous ceramics is its low porosity and uncontrollable pore gradient, which limits the wide application of gradient porous ceramics. In this study, the gradient porous ceramic skeleton (GPCS) was prepared by combining liquid crystal display (LCD) 3D printer with liquid silicon infiltration (LSI). Experimental results showed that the mass of ceramic powder in the ceramic slurry with optimal printing performance accounts for 45% of the mass of photosensitive resin, and the thermal decomposition rate of photosensitive resin is faster in the range of 300–450 °C. Furthermore, the effect of LSI temperature on the composition, microstructure and mechanical properties of GPCS was investigated. The GPCS is expected to be applied in the fields of energy storage, heat transfer and biofouling, among others.  相似文献   
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