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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.
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   
3.
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   
4.
Soybean agglutinin (SBA) protein, also known as soybean lectin, is regarded as an anti‐nutrient due to its negative effect on the ability of monogastric animals to gain weight following consumption of raw soybean seed. Historically, SBA has been measured using a time‐consuming and cumbersome hemagglutination procedure. The objective of our research was to obtain a validated methodology that is precise and accurate in the measurement of SBA while allowing minimally equipped laboratories to effectively conduct the analysis, thus our focus was on evaluating an existing commercially available ELISA, an enzyme‐linked‐lectin‐assay (ELLA), and a hybrid ELISA/ELLA. A new ELLA technique that can detect and quantify lectins was chosen and modified specifically for the quantitation of SBA in soybean seed. The proposed ELLA methodology is similar to a standard sandwich ELISA, and uses polyacrylamide‐linked N‐acetylgalactosamine (Gal–NAc–PAA) for a capture phase and the biotinylated version (Gal–NAc–PAA–Biotin) for detection. Based upon the validation data, the ELLA method can precisely and accurately determine soybean lectin levels in soybean seed. The validated ELLA method was used to quantify SBA in nine commercial soybean varieties introduced between 1972 and 2008 and demonstrated that the natural variability of SBA is subject to the effects of genotype and environment.  相似文献   
5.
天然纤维增强复合材料亚麻纤维具有良好的抗冲压强度和自洁防腐功能,延伸率和密度也较小,选用其替换由45号钢制作的煤矿井下探测机器人的主车体,在保证主车体性能要求的前提下,质量减少190.5 kg,占主车体质量的80.9%。  相似文献   
6.
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   
7.
Auto cascade refrigeration (ACR) cycle with phase separators is widely used in the cryogenic system. The compo-sition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of infinite volume of phase separator, ACR system with one phase separator is simulated in this paper. The variation of refrigerant composition under different valves opening is obtained. A related experimental system is set up to verify the variation. The result shows that when the valve opening connected to the evaporator increases or the valve opening under the phase separator decreases, the low-boiling component concentration of the working mixture passing through the compressor and condenser increases, while the high-boiling component concentra-tion decreases. Furthermore, the variations of condensation pressure and evaporation pressure under different valves opening are also observed. This paper is helpful to deepen the understanding of ACR system.  相似文献   
8.
利用金属原位分析技术和钻孔化学分析方法对高淬透性轴承钢GCr15SiMn的Φ450 mm连铸圆坯和Φ130 mm圆钢的C、Si、Mn、Cr元素横截面的分布情况进行分析。采用推力片式接触疲劳试验机进行了材料的接触疲劳寿命测试。结果表明:GCr15SiMn连铸圆坯C元素的偏析倾向较大,易产生中心正偏析,而Cr、Si、Mn元素的偏析倾向较小。通过采取稳定低过热度浇铸、三段强电磁搅拌等措施,铸坯的中心碳偏析得以改善。采用(1240±20)℃×5 h高温扩散、初轧首道次变形量≥90 mm大变形轧制的Φ130 mm圆钢的碳偏析可以得到进一步的改善,试验钢在5.3GPa高应力负载下的接触疲劳额定寿命L10达到3.58×106次,接近电渣重熔钢的水平。  相似文献   
9.
利用JMatPro热力学计算软件和相应的铝基合金数据库,在固溶温度475℃下,计算了S(Al2CuMg)、Al7Cu2Fe、Mg2Si和AL3MDO23等第二相在7050铝合金中的相含量,研究了Zn、Mg、Cu、Fe、Si和Zr等合金元素对第二相相含量的影响规律,并建立了第二相含量与合金元素含量之间的关系回归方程。研究结果表明:当控制Mg含量为2.4%~2.6%、Zn含量为6.4%~6.7%、Cu含量为2.0~2.2%、Zr含量为0.12%、Fe含量≤0.08%、Si含量≤0.06%时,可减少7050铝合金平衡状态下生成的S(Al2CuMg)相含量≤0.4%、Al7Cu2Fe相含量≤0.106%、Mg2Si相含量≤0.103%、AL3MDO23相含量为0.192%。并优化出7050铝合金成分范围:Al-(6.4%~6.7%)Zn-(2.4%~2.6%)Mg-(2.0~2.2%)Cu-(≤0.08%)Fe-(≤0.06%)Si-0.12Zr-(≤0.1)Mn-(≤0.04)Cr-(≤0.06)Ti。  相似文献   
10.
传统剪纸艺术是民俗文化的形象载体之一,维系藿整个民间艺术基本源头的文化根基,也是现代平面设计取之不尽、用之不竭的灵感宝藏。而当代艺术设计中的体积感、空间感对立体剪纸又有着引领式的启发作用,二者相互借鉴,便剪纸艺术更加多元化。如果单纯的将民俗剪纸艺术与二维平面进行对比和研究,可以更好更有创意的弘扬传统剪纸艺术,也可以将平面设计创作的更具视觉传达性、民族性、世界性。当代的立体剪纸即传承了传统剪纸的精髓又借鉴三维设计中立体构成的各个元素和形式,开拓了剪纸艺术的新天地。  相似文献   
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