表面活性剂对壳聚糖-乳清分离蛋白-纳米TiO2复合膜保鲜性能的影响

为研究表面活性剂对壳聚糖-乳清分离蛋白-纳米TiO2复合膜（chitosan-whey protein isolate-nano TiO2composite film,CWTF）在果蔬保鲜应用中性能的影响,将表面活性剂吐温（tween,TW）20、TW60、TW80、TW85分别添加到CWTF成膜液中,测定制备复合膜的拉伸强度、断裂延伸率、透明度及透水性能,并分析表面活性剂对CWTF性质的影响。将加有不同表面活性剂的CWTF涂膜液涂覆到鲜切雷竹笋上,测定其贮藏过程中的质量损失率。结果显示,添加表面活性剂后CWTF表面光滑程度均有不同程度的劣变,按照膜机械性能及透水性能等从优到劣的排序依次为CWTF、CWTF-TW20、CWTF-TW85、CWTF-TW80、CWTF-TW60。涂膜实验结果表明,涂膜组雷竹笋的质量损失率均低于未涂膜组,不同涂膜处理的雷竹笋的质量损失率与膜性质呈负相关。TW20对CWTF的破坏作用最小,为适宜添加表面活性剂,适宜添加体积分数为0.1%。     

聚赖氨酸在鲜切竹笋保鲜中的应用研究

本文采用聚赖氨酸对鲜切竹笋进行处理,并用保鲜膜包装后在4℃储藏保鲜;实验表明:100mg/L的聚赖氨酸对鲜切竹笋中微生物有很好的抑制作用;聚赖氨酸应用于鲜切竹笋中,可以减轻水分的损失;经处理过的鲜切竹笋L值以及a值均高于对照;断裂力、硬度和刚度有较好的相关度,而粘滞性、断裂形变、回复形变与其他指标的相关度较差。     

基于动态基准圆的机器人足球射门算法研究

为提高足球机器人的射门成功率,在分析了几种射门算法存在不足之处的基础上,引入动态基准圆的概念,提出了一种运动轨迹采用近似阿基米德螺线的射门算法．仿真结果表明,该算法在球静态和动态两种情况下均能缩短射门机器人的运动路径,增大击球的冲量,提高射门成功率．     

Growth and dry matter partitioning of Pinot Noir (Vitis vinifera L.) in relation to leaf area and crop load

Treatments varying source:sink ratio (leaf number per vine in relation to crop load) on container-grown Pinot Noir grapevines produced differences in vine growth and dry matter accumulation and partitioning. Vines with (+) and those without (-) fruit were subject to a range of leaf removal treatments. All treatments retained leaves at nodes 1–4 from the shoot base and then had: 100% (control); 66%; 33%; or 0% leaves retained from node 5 to the apex of the shoot. Leaf removal was done as leaves appeared. Leaf removal reduced vine weight. The presence of crop and the number of leaves influenced nodes per shoot and dry weight of the shoots. Removal of leaves did not influence shoot length although un cropped vines were larger in all of the above categories. Removal of either leaves or crop had an impact on leaf number, area per vine, area per leaf and leaf dry weight.'crop' vines carried fewer, and smaller leaves then the 'crop' vines. Carbon partitioning between above ground vegetative organs and roots followed the same relationship, regardless of harvest date, crop status or defoliation treatment. The 'crop 33% leaf retained' vines compensated for leaf removal by increasing their leaf size and dry weight over the '66% leaf retained' and the control.     

Optimization on the Conversion of Bamboo Shoot Shell to Levulinic Acid with Environmentally Benign Acidic Ionic Liquid and Response Surface Analysis

Levulinic acid (LA) has been identified as a promising green, biomass derived platform chemical. Response surface analysis (RSA) with a four-factor-five-level central composite design (CCD) was applied to optimize the hydrolysis conditions for the conversion of bamboo (Phyllostachys Praecox f. preveynalis) shoot shell (BSS) to LA catalyzed with ionic liquid [C₄mim]HSO₄. The effects of four main reaction parameters including temperature, time,C_[C4mim]HSO4(initial [C₄mim]HSO₄ concentration) and X_BSS (initial BSS intake) on the hydrolysis reaction for yield of LA were analyzed. A quadratic equation model for yield of LA was established and fitted to the data with an R² of 0.9868, and effects of main factors and their corresponding relationships were obtained with RSA. Model validation and results of CCD showed good correspondence between actual and predicted values. The analysis of variance (ANOVA) of the results indicated that the yield of LA in the range studied was significantly (P<0.05) affected by the four factors. The optimized reaction conditions were as follows: temperature of 145 ℃, time of 103.8 min,C_[C4mim]HSO4 of 0.9 mol·L^-1 and X_BSS of 2.04% (by mass), respectively. A high yield [(71±0.41)% (by mol), triplicate experiment] was obtained at the optimum conditions of temperature of 145 ℃, time of 104 min,C_[C4mim]HSO4 of 0.9 mol·L^-1 and X_BSS of 2% (by mass), which obtained from the real experiments, concurred with the model prediction [73.8% (by mol) based on available C₆ sugars in BSS or 17.9% (by mass) based on the mass of BSS], indicating that the model was adequate for the hydrolysis process.     

浅谈"篮球三分球"的心理训练

本文阐述了心理训练对篮球三分球的很重要作用,总结了在篮球三分球训练过程中所采取的种种心理训练方法。     

自组织映射(SOM)型神经网络的实现

文章讨论了应用于自组织映射型神经网络的训练算法,该算法通过计算获胜神经元来找到最接近输入模式的节点,然后通过对网络连接权值的自组织,训练一个自组织竞争的神经网络,该网络通过一组输入数据可自行训练形成一个神经网络模型.     

SOS：模糊图象反扩散恢复的“搜寻—单击”算法

为了对模糊图象进行高保真度的复原,研究了讨论了一种模糊图象的反扩散恢复算法;该算法首先以图象模糊的尺度为准,在比较为逐次递推算法和传统的单击算法的基础上,给出了它们的适应范围,进而提出了“搜寻－单击”算法,它用逐步逼近方式来探定未知的模糊尺度,然后以尺可能小的累积误差完成反扩散计算,从而实现了模糊图象恢复的盲处理,最后,采用自然模糊与人工模糊的图偈对恢复算法进行了验证,包括算法对模糊尺度的灵敏度算法的有效应用范围,以及纹理结构或景深偏差变化的模糊图象经恢复处理后的效果比较等,试验结果表明对数字图象作为SOS反扩散恢复处理可产生常规光学摄影技术所不可能取得的场景清晰度。     

射压造型数值模拟

射压造型是铸件生产中的现代化造型方法之一.射压造型包括用射砂进行充填及预紧实和高压压实进行砂型最终紧实.本文利用两相流理论模拟出射砂预紧实后的密度场分布;并采用分区建模的思想,结合型砂的本构关系试验,利用有限元方法,计算出砂型内二维的应力分布状况.     

压铸机压射机构的改造及其压射控制

如何在现存压铸机的基础上,进行压射机构的改造并对压射实现自动控制,这是一个很有研究意义的问题。为此,本文研究了液态金属压铸机压射结构的重新设计及其实时控制,在理论上设计 一套对压射进行实时控制的系统,文章重点研究了该系统的组成、基本原理及其特点。