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981.
火焰原子吸收光谱法测定钢材中锰含量已成为一种广泛应用于检验检测领域的快速分析方法,在检测过程中,校准曲线的绘制至关重要。本文介绍了火焰原子吸收光谱法测定钢材中锰含量的两种校准曲线的绘制方法,并进行了对比。  相似文献   
982.
In the United States, mechanical foaming is the most popular method for producing warm mix asphalt, which is the latest technology implemented to reduce the production temperature and/or enhance the compactability of asphalt mixtures. Three commonly used commercially available laboratory foamers to produce asphalt foams include the Wirtgen WLB 10S (Wirtgen foamer), the InstroTek Accufoamer (InstroTek foamer) and the Pavement Technology Inc. Foamer (PTI foamer). Though these foamers have been widely used in research studies and construction practice, it is still unknown whether they produce asphalt foams with the same quality and quantity. In this study, asphalt foaming characteristics produced by these three laboratory foamers were measured using a non-contact test set-up consisting of a laser device and a digital camera, and compared in terms of instantaneous volume expansion, foam stability and surface area evolution of foam bubbles. Additionally, the workability, coatability and mechanical performance of foamed mixtures prepared using these same laboratory foamers were compared against the conventional hot mix asphalt (HMA). Test results indicated that foamed asphalts produced by the Wirtgen foamer had the largest volume expansion and greatest foam stability, followed by those produced by the InstroTek foamer and the PTI foamer. The optimum foaming water content (Wopt) was determined for each laboratory foamer based on the workability and coatability results of the corresponding foamed mixtures. In addition, the performance evaluation of the foamed mixtures produced at Wopt values indicated equivalent mixture stiffness but greater moisture susceptibility as compared to the conventional HMA.  相似文献   
983.
近些年随着人们生活水平的提高,中国人在美容方面的需求不断加大,使得医学美容行业的发展极具活力,与之相应的美容医疗设备及技术的未来市场容量将非常可观。  相似文献   
984.
985.
Investigating differential treatment in rental housing markets is important to ensure that renters are not discriminated against based on their personal characteristics. However, little Australian research has focused systematically on this question. This paper reports the results of a study that used paired tests to estimate the extent of differential treatment of Anglo, Indian, and Muslim Middle Eastern renters in the Sydney metropolitan housing market. We find statistically significant differences in treatment on several measures, including the likelihood an agent will offer an individual appointment, will provide additional information about other housing, will provide additional information about completing the application form, and will contact a prospective renter after an inspection.  相似文献   
986.
Yin  Jun  Lai  Zhihui  Zeng  Weiming  Wei  Lai 《Multimedia Tools and Applications》2018,77(1):1069-1092
Multimedia Tools and Applications - Dimensionality reduction techniques based on sparse representation have drawn great attentions recently and they are successfully applied to biometric...  相似文献   
987.
Xu  Y. J.  Wang  Z. J.  Wu  G. D.  Yin  J. P.  Dong  F. D.  Jin  Y. X. 《Strength of Materials》2019,51(4):616-623
Strength of Materials - The aftereffect damage efficiency of shaped charge jets formed with the conventional metal liner against light armor is quite low. The validity of the PTFE-copper powder...  相似文献   
988.
Information Systems and e-Business Management - Since online reviews have become an increasingly important information source for consumers to evaluate products during online shopping, many...  相似文献   
989.
Sorghum (Sorghum bicolor) is known as a major feedstock for biofuel production. To improve its biomass yield through genetic research, manually measuring yield component traits (e.g. plant height, stem diameter, leaf angle, leaf area, leaf number, and panicle size) in the field is the current best practice. However, such laborious and time‐consuming tasks have become a bottleneck limiting experiment scale and data acquisition frequency. This paper presents a high‐throughput field‐based robotic phenotyping system which performed side‐view stereo imaging for dense sorghum plants with a wide range of plant heights throughout the growing season. Our study demonstrated the suitability of stereo vision for field‐based three‐dimensional plant phenotyping when recent advances in stereo matching algorithms were incorporated. A robust data processing pipeline was developed to quantify the variations or morphological traits in plant architecture, which included plot‐based plant height, plot‐based plant width, convex hull volume, plant surface area, and stem diameter (semiautomated). These image‐derived measurements were highly repeatable and showed high correlations with the in‐field manual measurements. Meanwhile, manually collecting the same traits required a large amount of manpower and time compared to the robotic system. The results demonstrated that the proposed system could be a promising tool for large‐scale field‐based high‐throughput plant phenotyping of bioenergy crops.  相似文献   
990.
本文简述了可再分散乳胶粉的性能。着重介绍了可再分散乳胶粉的制备,包括单体及配方的选择、聚合方法和干燥工艺,综述了可再分散乳胶粉的改性及其在建筑腻子、外墙外保温材料、内外墙装饰材料、地坪材料等方面的应用。指出以水溶性高分子为乳液聚合主要稳定剂的乳液聚合是一种新的思路。  相似文献   
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