锅炉汽温的影响因素以及运行调整

叙述了发电厂影响锅炉汽温的主要因素,提出了调整汽温的措施。     

Wheat Variety and Barley Malt Properties: Influence on Haze Intensity and Foam Stability of Wheat Beer

Laboratory wheat beers were brewed with different wheat varieties of different protein content (8.7–14.4%) and with five different barley malts, varying in degree of modification (soluble protein: 3.9–6.9%). In a first series of experiments, it was investigated whether wheat positively influences the foam stability, a major characteristic of wheat beers. NIBEM and Rudin (CO₂) foam analyses revealed that the effect of wheat on foam stability depended on the barley malt used for brewing. When using malt with high foaming potential, wheat exerts a negative influence. However, wheat added to over‐modified malt with less foam promoting factors, ameliorates beer foaming characteristics proving that wheat contains foam active compounds. In addition, Rudin (N₂) values suggested that wheat positively influences foam stability by decreasing liquid drainage, probably caused by a higher beer viscosity and/or a finer foam bubble size distribution. Furthermore, the haze in wheat beers, which is another important quality characteristic of these beers, was investigated. Permanent haze readings of the 40% wheat beers were lower than 1.5 EBC haze units. For 20% wheat beers, an inverse relation between the permanent haze (9.4–19.3 EBC haze units) and the protein content of the wheat was established. The barley malt used for brewing also influenced permanent haze readings. A positive correlation between the modification degree of the malt and the permanent haze intensity was found. It was concluded that the choice of raw materials for wheat beer brewing considerably influences the visual properties of the beer.     

The effect of Uncinula necator (powdery mildew) and Botrytis cinerea infection of grapes on the levels of haze-forming pathogenesis-related proteins in grape juice and wine

Powdery mildew on Chardonnay grapes resulted in increased levels of a grape thaumatin-like protein, VvTL2, in the free run juice compared to that from uninfected grapes. These increased levels persisted through winemaking and at the highest level of infection (> 30% of bunches infected) had a significant impact on the haziness in the wine following a heat test. Infection of Cabernet Sauvignon grapes (1–20% of bunches infected) did not affect the protein concentration of free run juice, and only traces of pathogenesis-related (PR) proteins remained detectable in the Cabernet Sauvignon wines from either infected or healthy grapes. In contrast, infection of Chardonnay or Semillon grapes by Botrytis cinerea in the vineyard resulted in decreased levels of all PR proteins in the free run juice and in a total protein extract from infected berries compared to that from uninfected grapes. Similar trends were observed when B. cinerea was grown in the laboratory on surface-sterilised berries or in filter-sterilised juice.     

Characterisation of the Colloidal Haze in Commercial and Pilot Scale Belgian White Beers

Hazes from four commercial Belgian white beers were studied. Proteins (7–74%) and polyphenols (1.1–7.7%) were the major components, although hazes with a high content of glucose polymers also occurred. The glucose polymers are mainly starch or degraded starch (9–65%) and only to a minor extent β‐D‐glucan (0‐0.5%). Arabinoxylans and metal ions (mainly calcium) were minor constituents. The hazes also contained arabinogalactan‐peptide in minor quantities due to the large level of wheat used in the grist. A high mannose content (0.9‐3.3%), originating from yeast cell wall mannans, was also found in the hazes. Characterisation of the haze of three pilot scale brews with different production processes showed that the composition of the hazes was strongly influenced by the process employed. Hazes can be enriched in proteins or starch/dextrins by changing the raw materials and/or the brewing process.     

无反射蒙砂玻璃

采用稳定、廉价的化学蚀刻方法改变玻璃表面的形状,达到无反射和提高透光率的效果。研究了蚀刻后表面的晶体结构、形貌,探讨了时间、温度对化学蚀刻结果的影响,提出了控制化学蚀刻表面形状对光无反射、增透的重要性和几何模型。     

彩色图像去雾清晰化研究

为了解决雾霾天气的影响下成像设备采集的图像容易出现的降质及色彩失真问题, 并从有雾图像中增强其细节信息, 提高原图像的对比度和清晰度. 将彩色图像RGB通道分别做相应的图像增强算法处理, 全局直方图均衡化把整体的灰度直方图进行均匀分布的处理, 小波变换算法对彩色图像进行多层次分解, 多尺度Retinex算法通过高斯函数...     

A Haze Feature Extraction and Pollution Level Identification Pre-Warning Algorithm

The prediction of particles less than 2.5 micrometers in diameter (PM2.5) in fog and haze has been paid more and more attention, but the prediction accuracy of the results is not ideal. Haze prediction algorithms based on traditional numerical and statistical prediction have poor effects on nonlinear data prediction of haze. In order to improve the effects of prediction, this paper proposes a haze feature extraction and pollution level identification pre-warning algorithm based on feature selection and integrated learning. Minimum Redundancy Maximum Relevance method is used to extract low-level features of haze, and deep confidence network is utilized to extract high-level features. eXtreme Gradient Boosting algorithm is adopted to fuse low-level and high-level features, as well as predict haze. Establish PM2.5 concentration pollution grade classification index, and grade the forecast data. The expert experience knowledge is utilized to assist the optimization of the pre-warning results. The experiment results show the presented algorithm can get better prediction effects than the results of Support Vector Machine (SVM) and Back Propagation (BP) widely used at present, the accuracy has greatly improved compared with SVM and BP.     

醋酸对绒面AZO薄膜表面织构均匀性的影响研究

以0.5%的稀盐酸中加入一定量醋酸后的溶液为腐蚀液,对利用直流磁控溅射方法制备的平面掺铝氧化锌(AZO)薄膜进行表面织构,并对加入醋酸后的AZO薄膜表面织构均匀性和反应机理进行研究。结果表明:在0.5%稀盐酸中所加醋酸量与盐酸体积比为0.5:1时,对平面AZO薄膜腐蚀45 s能获得更均匀陨石坑状绒面结构,且有较高绒度;腐蚀液中较水分子大得多的醋酸分子的空间位阻作用在一定程度上能减缓腐蚀速率,使得比加醋酸前获得的AZO薄膜绒面更均匀。     

浅析户式新风除霾机的设计

本文介绍了当前主流的户式住宅用空气处理产品,分析探讨了几种典型的净化方案和新风方案。并阐述了设计新风除霾机时应注意的一些要点。     

雾霾对输变电设备外绝缘特性影响机理综述

为深入分析雾霾对外绝缘特性的影响机理,调研了国内外关于雾霾对输变电设备外绝缘特性的相关研究。从雾霾的形成与沉降、雾霾的模拟、其对输变电外绝缘特性的影响几个方面进行探讨。结果表明:雾霾主要是由人类活动产生大量的污染物质在一定相对湿度的气象条件下形成的,雾霾天气下绝缘子放电主要以沿面闪络为主,雾霾沉积在绝缘子表面或漂浮在绝缘子片间空气间隙中会降低绝缘子的污闪电压。建议在绝缘子分布密集的雾霾天频繁区域加强环保工作,采取有效措施防止雾霾对输变电设备外绝缘特性的影响,保证绝缘子安全、可靠、稳定的运行。