修正的连接性指数G用于脂肪醇气相色谱保留指数的预测

修正的连接性指数被定义为:G=0G+(δ-1)-0.5,G与25种脂肪醇在6种固定相(SE-30,OV-3、OV-7、OV-11、OV-17、OV-25)上的气相色谱保留指数显著相关,相关系数分别为0.9931、0.9925、0.9914、0.9891、0.9887和0.9843.所建定量结构-保留关系模型为脂肪醇气相色谱保留指数的预测提供了有效的方法.     

小麦碱性水保持力与品质性状和产量性状的相关性分析

利用小麦京771×Pm97034产生的重组自交系群体,对小麦碱性水保持力与其他品质性状和产量性状在重组自交系群体中的相关性进行了研究。研究结果表明:碱性水保持力与蛋白质含量和籽粒硬度呈显著和极显著正相关(r=0.189,r=0.253),与谷蛋白膨胀指数表现出了极显著的负相关(r=-0.232,P<0.01);与面筋指数、Zeleny沉淀值呈不显著的负相关;与湿面筋含量、膨胀势呈不显著的正相关。碱性水保持力与各产量构成因素的相关性均未达到显著水平,其中除与穗长呈不显著的正相关外,与其他产量性状均呈不显著的负相关。     

Impact of corrections for dynamic selection bias on forecasts of retention behavior

We investigate the impact of corrections for dynamic selection bias on forecasting accuracy in a multi‐period stay/leave model. While corrections for selection bias are needed for consistent coefficient estimates, they do not necessarily produce more accurate forecasts than uncorrected techniques. Theorem 1 shows that, apart from estimation errors, a shrinkage principle applies: the heterogeneity restriction imposed by uncorrected and combination techniques improves accuracy for forecasting individuals that leave, and hurts accuracy for forecasting individuals that stay. This has important implications for decision making because of the potential for asymmetric losses. We also present an illustrative empirical application and results from Monte Carlo experiments. We find that differences in relative accuracy vary directly with the degree of selection bias and inversely with the percentage of the initial population that stays. Copyright © 2007 John Wiley & Sons, Ltd.     

啤酒花头香成分的研究

本文主要研究两种啤酒花的香气成分,通过循环吸附法采集样品,用GC/MS初步定性,然后用双柱保留指数及标样叠加法对照,共鉴定出113个啤酒花头香成分,其中新检出65个化合物。对113个成分中的90个化合物比较了不同时间的含量变化。     

EFFECT OF MODAL COLLOIDAL SUBSTANCES ON THE PROPERTIES OF NEWSPRINT

1.INTRODUCTIONIn modern papermaking of newsprint, pitch and stickies control draws more attention with higher proportion of mechanical pulp and second fibers in furnishes. The accumulation of colloidal substance in process could affect the production and products most introduced by wood containing pulp and sec-ondary fibers. Sources of in-process colloid were complex and extensive, including lignin, hydropho-bic extraction, coating, adhesive and other additives[1-3]. Pitch was more seriou…     

无污泥持留序批式反应器的脱氮理论模型

提出无污泥持留序批式反应器并建立其动力学理论模型．模型推导表明：反应器的脱氮效能是水力停留时间、曝气比率、进水周期等操作因子的函数；通过调控水力停留时间、曝气比率等因素，能调节反应器的好氧菌筛选因子和厌氧菌筛选因子，完成硝酸菌的洗出和反硝化菌的积累．模型极限分析表明现有Sharon反应器的实质是反应周期为零的无污泥持留序批式反应器．以荷兰Dokhaven污水处理厂的Sharon反应器为例，模型计算结果表明在水力停留时间为2．6d、反应周期为2h、曝气比率为0．175时，厌氧菌筛选因子值为0．020，低于反硝化菌的最大比生长速率0．034，好氧菌筛选因子值为0．093，介于亚硝酸菌最大比生长速率0．137与硝酸菌最大比生长速率0．082之间，此时反应器的理论氨转化率为98．9％，总氮脱除率为97．6％．     

影响焦化废水处理的因素探讨

从水力停留时间、pH值、碱度、进水COD负荷等方面对影响焦化废水处理因素进行分析。     

USING COLLOIDAL LAYERED DOUBLE HYDROXIDES AS CATIONIC MICROPARTICULATE COMPONENT

INTRODUCTIONMicroparticulate retention aid systems have been widely accepted in papermaking industry. The typical microparticulate components include inorganic col-loidal silica (or structured colloidal silica sol[1], mont-morillonite[2] and organic micropolymers[3]. They are all negatively charged and form synergic retention ef-fects with either cationic starch or polyaminoamide. Yet, it is interesting to note that cationic microparti-cles also have been found to be effective in floccula…     

无甲醛防皱整理剂BTCA在棉织物整理中的应用研究

探讨自制防皱整理刘BTCA在棉织物整理中的应用，运用正交分析法对棉织物断裂强力保留率以及折皱回复角变化进行研究，确定BTCA整理液的最佳配比。