玉米薄层干燥特性对比试验研究

在热风薄层干燥试验平台上对玉米进行薄层干燥对比试验,采用单因素试验与正交试验相结合的方法,以玉米发芽率、裂纹率及干燥速率为指标,研究影响玉米干燥特性的主次因素,确定最优干燥工艺参数。试验结果表明:在玉米原始含水率不变的情况下,热风温度的影响最为显著。     

组挂式粮食干燥仓玉米籽粒自然干燥研究

新收获高水分玉米得不到及时干燥处理会引发严重霉变问题,影响农民增产增收。通过自然晾晒翻倒干燥、环境及粮堆内温湿度检测、水分检测、真菌孢子检测等技术方法,对目前研发的大农户晾粮干燥和安全储粮的新仓型——组挂式粮食干燥仓进行分析和评价,为组挂式粮食干燥仓推广应用提供理论依据。     

响应面法优化水/醇处理后汽爆玉米秸秆酶解的研究

为了提高水/醇处理后汽爆玉米秸秆的酶解还原糖产率,对其酶解条件进行了优化。通过响应面优化法确定了底物浓度为53.28g/L,纤维素酶用量为53.32FPU/g,酶解时间为60.45h时,还原糖产率可达672.36mg/g,与秸秆物料及汽爆后物料相比,酶解还原糖产率分别提高了179.21%和37.29%。化学组分及结构形貌分析表明：水/醇处理后物料纤维素含量显著增加,X射线衍射(XRD)和扫描电镜(SEM)结果表明经过水/醇处理后物料相对结晶度增高,但结构更有利于纤维素酶分子的吸附。     

控释肥料基施及普通尿素不同基追比对夏玉米产量及氮肥利用率的影响

研究了控释尿素和控释BB肥一次性基施后的肥料效果,以及普通尿素不同基追比对玉米产量和氮肥利用率的影响.研究结果表明:以33.3％普通尿素基施+33.3％大喇叭口期追施+33.3％抽雄期追施的处理最佳,产量最高达8 700 kg/hm2,氮肥利用率为34.3％.控释尿素基施处理和控释BB肥基施处理的氮肥利用率分别为41....     

烟气烘焙对玉米秆可磨性的影响规律研究

可磨性是生物质在现有燃煤机组规模化燃烧利用中必须考虑的问题之一。本文基于固定床反应器对玉米秆进行烘焙预处理,针对生物质单烧和与煤混烧两种技术路线,利用臼式研磨仪、全自动粒径筛分仪、纤维素分析仪和傅里叶红外光谱,研究了不同烘焙气氛、温度对燃料可磨性的影响。结果表明,相比于氮气,烟气能够在更低的烘焙温度下使玉米秆可磨性提升至接近于典型动力用煤,主要是由于烟气中的氧化性组分促进了纤维素、半纤维素的分解。当共磨时,煤颗粒表现出助磨的作用提升了玉米秆的可磨性,在较高温度或烟气烘焙条件下,混样的可磨性近似甚至优于煤。     

黄土旱区作物-水分模型

本文依据田间试验数据，采用Jensen模式，研究了黄土旱区冬小麦、春玉米这两种优势作物的 水分模型。研究结果表明，小麦在播种～返青期缺水敏感指数(λ)最大，对缺水最为敏感；拔节～抽穗期次之，然后是抽穗～灌浆期，而灌浆～成熟期和返青～拔节期的敏感性最小。总耗水量在320～420mm之间，灌水量为260～300mm左右、且分布在冬前和拔节～抽穗期是节水高产高效的灌水模式。玉米拔节-抽穗期和抽穗-灌浆期对缺水最敏感，拔节前和灌浆-成熟期敏感性小。说明拔节后到抽穗期补水对产量作用最大，其次为抽穗-灌浆期。这为黄土旱区制定灌溉制度提供了重要理论依据。     

丙烯酸丁酯与玉米淀粉的微波辐射接枝共聚合

研究了微波辐射下丙烯酸丁酯与玉米淀粉的干法接枝共聚反应,考察了辐射条件、引发剂配比及种类、单体配比、界面剂种类等因素对反应的影响,并对接枝产物进行了表征。     

Aerobic deterioration stimulates outgrowth of spore-forming Paenibacillus in corn silage stored under oxygen-barrier or polyethylene films

The occurrence of Bacillus and Paenibacillus spores in silage is of great concern to dairy producers because their spores can survive pasteurization and some strains are capable of subsequently germinating and growing under refrigerated conditions in pasteurized milk. The objectives of this study were to verify the role of aerobic deterioration of corn silage on the proliferation of Paenibacillus spores and to evaluate the efficacy of oxygen-barrier films used to cover silage during fermentation and storage to mitigate these undesirable bacterial outbreaks. The trial was carried out on whole-crop maize (Zea mays L.) inoculated with a mixture of Lactobacillus buchneri, Lactobacillus plantarum, and Enterococcus faecium. A standard polyethylene film and a polyethylene-polyamide film with an enhanced oxygen barrier were used to produce the silage bags for this experiment. The silos were stored indoors at ambient temperature (18 to 22°C) and opened after 110 d. The silage was sampled after 0, 2, 5, 7, 9, and 14 d of aerobic exposure to quantify the growth of endospore-forming bacteria during the exposure of silages to air. Paenibacillus macerans (gram-positive, facultatively anaerobic bacteria) was able to develop during the aerobic exposure of corn silage. This species was present in the herbage at harvesting, together with clostridial spores, and survived ensiling fermentation; it constituted more than 60% of the anaerobic spore formers at silage opening. During silage spoilage, the spore concentration of P. macerans increased to values greater than 7.0 log₁₀ cfu/g of silage. The use of different plastic films to seal silages affected the growth of P. macerans and the number of spores during aerobic exposure of silages. These results indicate that the number of Paenibacillus spores could greatly increase in silage after exposure to air, and that oxygen-barrier films could help to reduce the potential for silage contamination of this important group of milk spoilage microorganisms by delaying the onset of aerobic deterioration.     

响应面优化微波辅助提取玉米叶黄素工艺

基于微波辅助提取工艺,在萃取液中添加表面活性剂增加玉米黄粉中叶黄素的溶出,并用响应面法对提取工艺进行优化。对表面活性剂质量分数,微波时间和液料比3个因素进行Box-Behnken中心组合设计,分析3个因素对叶黄素提取率的影响。表面活性剂辅助微波提取玉米黄粉叶黄素的最佳工艺条件为：添加十二烷基硫酸钠质量分数1.15%,液料比14∶1（mL/g）条件下微波炉中高火提取时间6min,得到叶黄素的提取率为8.6%。在此条件下,玉米叶黄素的提取率得到有效提高,方便为实际生产提供一定的理论指导。     

脉冲电场处理对玉米淀粉结构特征和消化性的影响

实验以玉米淀粉为研究对象,经过30、40、50kV·cm-1的脉冲电场处理后,利用偏光显微镜观察、差示扫描量热仪等方法,研究了脉冲电场对玉米淀粉酶解特性及消化特性的影响。结果表明,经过脉冲电场处理之后,淀粉颗粒被破坏、结晶区特征减弱,糊化的温度和焓值也减小,同时,玉米淀粉的酶解率和RDS值均有所增加,而SDS值有所降低。