氧化玉米淀粉粘合剂稳定性的探究

探讨了氧化玉米淀粉粘合剂的稳定性的主要影响因素,初步分析其变质机理,以此为依据制备得到高稳定性的产品。     

玉米黄粉酶解液在黄原胶发酵生产应用的研究

以玉米黄粉酶解液为氮源应用于黄原胶发酵培养基，探讨了蛋白酶种类、玉米黄粉酶解液添加量和酶添加量等因素对其发酵黄原胶粘度和产胶率的影响，并优化了复配氮源的种类及其复配比例。结果表明，碱性蛋白酶水解液作为氮源发酵黄原胶的粘度和产胶率优于其它蛋白酶解液；当酶解液添加量为6%、碱性蛋白酶添加量为8kU时，发酵黄原胶的粘度和产胶率可以达到4235cp和24.4g/L。大豆蛋白与玉米黄粉酶解液复配效果优于与棉籽粉、豆粕粉、花生粉的复配；玉米黄粉酶解液与大豆蛋白复配比为3:7时，发酵黄原胶的粘度和产胶率可以达到5833cp和32.4g/L，与单独以大豆蛋白为氮源无明显差异。本研究为提高玉米黄粉资源利用率、降低黄原胶的发酵生产成本提供了新思路。     

玉米浆为有机氮源的L-乳酸发酵的研究

利用细菌厌氧发酵生产L-乳酸,以降低L-乳酸生产成本为主要目的,实验以玉米浆为有机氮源,以硫酸铵为主要无机氮源,研究了不同接种量对发酵过程的影响;并就以玉米浆替代酵母粉、豆粕水解液、生物素为有机氮源的L-乳酸发酵进行了对比研究实验,实验证明了玉米浆做为有机氮源用于L-乳酸发酵的可行性。在保证生产能力的同时,使用玉米浆为有机氮源对进一步降低L-乳酸生产成本,减少玉米浆对环境的污染进行了探索。     

玉米淀粉胶粘剂的改性研究

以玉米淀粉为主要原料 ,通过预糊化、氧化、加碱糊化进行化学改性 ,并加入稳定剂可制备固含量高、贮存稳定性好 ,具有一定初粘力和透明性的改性淀粉胶粘剂。本论文主要研究了改性玉米淀粉胶粘剂的主要成分配比及工艺条件对产品性能的影响。结果表明 :淀粉氧化前是否进行预糊化处理、氧化剂的用量、体系pH值、加碱糊化时碱液用量、稳定剂的种类和用量等对改性玉米淀粉胶粘剂性能影响较大。     

玉米芯木聚糖硫酸酯化条件的研究

用碱提法从玉米芯中提取木聚糖,采用氯磺酸吡啶法进行硫酸酯化,通过正交试验确定最佳工艺条件为:吡啶与氯磺酸摩尔比1∶1,温度65℃,时间6h;木聚糖硫酸酯wisX-S通过DEAESepharoseFF层析柱分离得到一个相对分子量为1.3×104的组分,硫酸基取代度为2.24。对此木聚糖硫酸酯进行红外光谱分析,结果显示在波数1259、1228和813cm-1处分别有S=O和C-O-S键的特征吸收峰。     

A phosphorus budget of a poultry farm and a dairy farm in the southeastern U.S., and the potential impacts of diet alterations

Current and potential environmental problems associated with P transport from lands receiving high application rates of animal waste are a major concern. Phosphorus management strategies are needed to reduce P loading on land. This study was conducted to compare on-farm P budgets for a modern broiler farm and a dairy farm under traditional diets and management practices. Phosphorus inputs, recycling and outputs were assessed for both farms. A typical broiler and a dairy farmer from North Carolina were interviewed and pertinent information for the study was obtained, in cooperation with extension agents, and other professionals associated with the farms. The annual on-farm P surplus for the broiler farm was 6,380 kg, while that for the dairy farm was 1,141 kg. This corresponds to an annual application of 65 kg P ha^–1 for the broiler farm and 20 kg P ha^–1 for the dairy farm in excess of removal. The potential for reducing P surpluses by the addition of phytase enzymes and/or the use of low phytic acid corn (Zea mays L.) feed in the broiler farm diet was also assessed. Estimates by animal nutritionists indicate that feed supplementation with phytase enzyme can reduce the broiler farm's P surplus by 33%. The use of low phytic acid corn can reduce the surplus by 49% and a combination of the two can reduce the surplus by 58%. In this study, the incorporation of soybean (Glycine max (L.) Merr.) and alfalfa (Medicago sativa) land into the waste utilization plan of the dairy farm decreases the annual P surplus from 20 to 9 kg P ha^–1. The use of new feed technology and expanding waste application to a larger land base can significantly alter the P budgets of broiler and dairy farms and reduce P surpluses, minimizing the risk of environmental problems.     

Structure-activity relationship observations for European corn borer moth pheromone and fluoro analogs via computer molecular modeling

Structure-activity relationship (SAR) observations were made for theZ-type European corn borer moth pheromone, (Z)-11-tetradecen-1-ol acetate, and a series of analogs with fluorination in the alcohol portion of the molecule. The attractiveness of these analogs and the pheromone was compared to the electrostatic potential map of the molecular mechanics (MM) minimized lowest energy conformation for each compound. A critical range of electrostatic potential on the protons of the double-bond appears to be essential for optimal acceptor fit and attractiveness.     

Antioxidant activity of red wine phenolic extracts towards oxidation of corn oil

The antioxidant activity of Xinomavro red wine phenolic extracts in corn oil stripped of tocopherols was evaluated. One wine extract, at 100 mg/L total phenolics, rich in phenolic acids and flavonols, inhibited the oxidation of corn oil stripped of tocopherols to a greater extent than butylated hydroxyanisole, at 200 mg/L. Moreover, another extract, at 100 mg/L total phenolics, rich in flavanols, flavonols and tyrosol, also exhibited high inhibitory action. The present results indicate that some red wine phenolics – such as phenolic acids, flavonols or flavanols – may be strong antioxidants in corn oil.     

农作物秸秆增强氟石膏复合材料的微观结构研究

将玉米秸秆加入改性后的氟石膏中，研究改性剂、玉米秸秆对氟石膏复合材料结构性能的影响；并用苯丙乳液对玉米秸秆纤维进行表面处理，用以改善基体材料和增强材料的界面结合状况，由此显著提高制品性能。     

基于多特征融合和SVM分类器的植物病虫害检测方法

针对农业领域植物病虫害检测问题,提出一种基于高清视频图像融合特征的支持向量机(SVM)的检测方法,实现农业生产中植物病虫害的快速检测。对每幅植物叶片图像的颜色、HSV、纹理和方向梯度直方图四种特征采用基于特征包的多特征融合方法,形成特征向量,并利用SVM分类器进行训练分类。对单特征与融合特征的SVM分类器性能进行试验比较,所提出的方法具有较高的准确率。