Brightness and Its Application

This paper provides a conception of brightness and puts stress upon application of brightness to science of illuminating engineering and actual illuminating engineering.     

木质素化学改性抑制杨木碱性过氧化氢机械浆返色的研究

中试系统制备了杨木碱性过氧化氢机械浆。分别在水相 /有机溶剂相 /气相等条件下 ,使用乙酐处理杨木化机浆 (原浆及硼氢化钠还原后纸浆 ) ,分别抄造成 60g/m2 纸片 ,测定了不同时间紫外线照射后试样白度。运用返色值 (PCno .)和白度稳定效果 (BSE)等指标评价处理后浆料的光学稳定性。研究结果表明 ,有机溶剂相和气相乙酰化后的纸浆 ,光学稳定性的提高程度取决于乙酐用量和反应时间即乙酰化程度。通过乙酰化 ,可以获取光学完全稳定的杨木化机浆。紫外漫射反射光谱表明 ,杨木APMP机械浆光诱导返色的主要原因是纸浆木质素中羰基和酚羟基团吸收紫外光后变化形成发色结构所致。还原配合纸浆乙酰化处理 ,可能成为防止高得率纸浆返色的工业应用方法     

热处理对圆盘豆地板材颜色的影响

采用过热蒸汽作为传热介质和保护气体,于160、180、200、220℃分别对圆盘豆木材进行热处理试验。结果表明,热处理后圆盘豆木材颜色发生明显变化。随着热处理温度升高,木材明度L*下降,红绿色品指数a*变化不明显,黄蓝色品指数b*下降,色差△E*增大,木材表面颜色加深,并且木材径面色差值大于弦面及横截面色差值,表面色差值大于其内部色差值。     

基于掩模及亮度校正算法的脐橙表面缺陷分割

【目的】 本研究旨在有效解决果皮有缺陷的水果图像在去除背景时部分缺陷被误分割为背景,以及水果表面缺陷难以有效分割提取的问题。【方法】 以I分量图来构建掩模模板,根据其灰度直方图信息,通过双峰法选择单一阈值（T=75）分以纽荷尔脐橙为研究对象,提出基于HSI颜色空间模型法去除背景割背景并填充孔洞得到掩模模板I_mask,然后掩模模板I_mask与I分量图通过点乘运算得到去除背景的I分量图;提出基于多尺度高斯函数图像亮度校正算法对去除背景后的I分量图像进行亮度校正,通过构建多尺度高斯函数滤波器,将去除背景后的I分量图与构建的多尺度高斯函数进行卷积运算即得到去除背景后的I分量图像表面光照分量图,最后将去除背景后的I分量图与得到的光照分量图进行点除运算即得到去除背景后的I分量图像亮度校正图;然后采用单一全局阈值法对脐橙表面缺陷进行提取。【结果】 基于HSI颜色空间模型法去除背景,可在有效去除背景的同时完好保留脐橙的表面信息,有利于后续操作;基于多尺度高斯函数的图像亮度校正算法分别对6种常见脐橙缺陷进行图像亮度校正后采用单阈值法提取缺陷,使不同灰度等级的脐橙表面缺陷一次性分割成功,其中分割率最高为100%,最低为88.5%,整体达92.7%。通过试验分析后发现造成部分误分割或漏分割的原因主要在于部分缺陷果缺陷处颜色较轻,与正常区域灰度差较小,从而造成漏分割;还有部分缺陷果由于缺陷面积小,在图像形态学处理过程被误认为是噪声而被去除;同时发现正常果的误判率也达到了10.8%,经分析发现误判的正常果表皮组织区域的褶皱位于图像的边缘区域,从而被误认为是边缘区域的缺陷,导致误判。【结论】 基于HSI颜色空间模型法去除背景及基于多尺度高斯函数的图像亮度不均校正算法对纽荷尔脐橙图像背景分割和去除背景后的I分量图像表面亮度校正均取得了较好的效果,能有效识别脐橙缺陷区域,为脐橙精确分级提供了技术支持,也为其他果品表面缺陷快速检测提供了一种新思路。     

MEASURING PROBABILITY OF SKY BRIGHTNESS IN CLASSIFICATION BY THE AVERAGE INSOLATION

According to the daily change law from curves for percentage insolation,this paper presents a new formula of the average insolation in the zones where the insolation is more than 70%. By means of the hourly observing data during two years for solar direct ratiation, cloudage and sunshine condition in seven zones different lighting climate,considering the vaper pressure and the altitude present the function of percentage insolation and the probability of four sky brightness classification,this formula has a certain precision to be proved by observation.     

马尾松SGW高白度全无氯漂白研究

对马尾松磨石磨木浆(SGW)进行了单段H2O2漂白和2段H2O2漂白试验，研究了不同预处理方法和条件对H2O2漂白效果的影响，提出了最佳的预处理工艺；同时还研究了以EDTA和MgSO4作为金属螯合剂改善H2O2漂白效果，进而确定了H2O2漂白的最佳工艺参数．结果表明，应用EDTA和MgSO4作为金属螯合剂，SGW经预处理后，采用两段H2O2漂白，漂后纸浆白度可由原浆的47．8％提高到74．5％，从而使制得的漂白浆能满足低定量高白度胶印新闻纸和其他高级纸种的生产要求．结果还表明，与传统CEH3段漂白相比，漂白废水中的CODCr减少78．5％，BOD5减少97％，且不再含有可吸附的有机卤化物(AOX)．     

圆盘豆热处理材颜色变化及其变化机理

试验采用过热蒸汽作为传热介质和保护气体,对圆盘豆木材进行热处理,热处理温度为160℃、180℃、200℃、220℃,热处理时间为2h、4h、6h、8h,并采用紫外光谱和气-质联用对圆盘豆木粉抽提物进行分析。结果表明,热处理后圆盘豆木材颜色发生明显变化。随着热处理温度升高,木材明度L*下降,红绿色品指数a*变化不明显,黄蓝色品指数b*下降,色差△E*增大,木材表面颜色加深,其主要原因是木素及木材抽提物发生了氧化、还原反应。     

Effect of quinoa flour on gluten-free bread batter rheology and bread quality

A new gluten-free bread formulations composed of quinoa, buckwheat, rice flour and potato starch were developed in the present study. Rheological characteristics of the bread batter with increasing amount of quinoa were determined; storage (G′) and loss modulus (G″) values were also measured for investigation of viscoelastic properties. To evaluate the quality of breads; technological and physical (bake loss %, specific volume, texture, microstructure, color), chemical (protein, moisture, ash) and sensory properties were determined. All batter formulations independent of the quinoa amount exhibited pseudoplastic behavior, and G′ values were found to be higher than G″ values in expressing the solid like characteristics of the batter. Amount of quinoa flour addition did not present significant difference on bake loss%, specific volume and protein content (p>0.05); however, 25% quinoa flour bread displayed better results with its higher sensory scores and softer texture. Quinoa and buckwheat flour mixture therefore will be a good alternative for conventional gluten-free bread formulations.     

Relationship Between Spectral Data from an Aerial Image and Soil Organic Matter and Phosphorus Levels

Early ventures into site-specific management involved fertilizer management decisions based on soil chemical properties characterized by some form of grid sampling. This is both labor and capital intensive and practitioners quickly began investigating other methods to get a measure of spatial variability. Aerial photographs, which were mainly used to evaluate and assess crop status, allow for the collection of whole-field data at relatively low cost. Our objective is to determine what relationships exist between aerial spectral data and intensive grid soil test results and whether this information can be used to improve future soil sampling strategies. Soil-test organic matter (OM) and Bray-1 P concentrations were measured on soil samples taken using an alternating 12.2- by 24.4-m grid in late March 1994 from a quarter section under center pivot irrigation. Spectral data were collected in the spring of 1996 prior to planting using a multispectral network of digital cameras. Correlations of brightness values from the blue, green, and NIR bands with both OM and Bray-1 P were significant, but relatively low. Normality tests revealed that brightness values for the spectral data sets were generally evenly distributed while those of the soil test OM and Bray-1 P were positively skewed. Many of the very high soil-test data values were due to past management. When those values were removed from the database, greater correlations between spectral data and soil test data were obtained. These results substantiated that aerial imagery can be used to improve sampling strategies, but it must be used in conjunction with existing knowledge and past management histories.     

化学还原处理改善杨木过氧化氢机械浆白度稳定性研究

分别采用硼氢化钠、亚硫酸氢钠及其混合物处理杨木APMP漂白机械浆，优化了处理条件，研究了不同化学药品对纸浆还原处理后改善白度稳定性效果。结果表明硼氢化钠处理杨木漂白化机浆不但能够显著改善其白度稳定性而且对纸浆具有漂白作用。加入亚硫酸氢钠混合处理纸浆可大幅度减少硼氢化钠用量，并能取得类似的改善纸浆白度稳定性效果。杨木碱性氧化氢漂白机械浆光诱导返色有其固有特点，傅立叶红外光谱显示，纸浆木质素中的羰基和酚羟基结构基团是引起纸浆光诱导返色的主要原因。