碱性蛋白酶酶解虾下脚料的工艺

研究了碱性蛋白酶水解虾下脚料的工艺。结果表明:酶解前对虾下脚料进行超声处理可以提高水解度。通过单因素和正交试验对酶解工艺参数进行优化,确定碱性蛋白酶水解虾下脚料的最佳条件为温度60℃、加酶量0.4%(g/g,酶/虾下脚料)和酶解时间4.5h。     

响应面法优化中性蛋白酶酶解谷朊粉工艺研究

本文采用Box-Behnken设计和响应面分析法(RSM),以谷朊粉为原料,用中性蛋白酶制备小麦肽,对其水解工艺进行优化。以水解度为响应值,设计了4因素(加酶量、底物浓度、加酶时间、加酶温度)3水平的中心组合响应面试验。通过优化组合得到最佳水解条件为:加酶量6985.77U/g、底物浓度为6.99%、酶解时间3.44h、酶解温度45.65℃。水解条件经优化后,水解度为10.43%,而实测水解度平均为10.40%,试验值与预测值基本相符。     

脂肪酶催化酶解稻米油制备甘油二酯的研究

利用TLIM脂肪酶对稻米油进行催化水解,生成甘油二酯。研究了酶解时间、酶解温度、加酶量和加水量对酶解反应的影响。通过单因素与正交试验得出TLIM脂肪酶水解稻米油的最佳反应条件:酶解时间为10h、酶解温度为60℃、脂肪酶用量为4.5%和去离子水用量为10g,在此条件下,水解转化率为90.3%。     

酶法制备大米抗氧化肽的蛋白酶筛选

通过酶法制备进行大米抗氧化肽蛋白酶的筛选。以大米蛋白为原料、酶解液对DPPH自由基清除率为指标,从风味蛋白酶、中性蛋白酶、胰蛋白酶、复合蛋白酶、碱性蛋白酶、木瓜蛋白酶和胃蛋白酶等7种蛋白酶中,筛选出中性蛋白酶为最佳用酶。通过试验得出最佳的酶解反应条件为：底物质量浓度1.0 g/(100mL)、加酶量8%、pH值6.0、温度60℃、酶解时间30min。酶解液稀释15倍对DPPH自由基的清除率为89.45%,酶解液清除     

巴旦木肽的酶法制备工艺及其性质研究

利用蛋白酶水解巴旦木蛋白制备巴旦木肽。比较碱性蛋白酶、中性蛋白酶、风味酶、木瓜蛋白酶和植物蛋白酶水解巴旦木蛋白的进程曲线,结果显示碱性蛋白酶的水解效果最好,正交试验表明其较佳作用条件为:底物浓度20%、酶浓度4%、pH值9.5和酶解温度60℃,在此条件下水解度为36.6%。巴旦木肽具有溶解性较好和黏度较低的特性,可以在食品中广泛应用。     

牦牛乳酪蛋白酶解工艺优化及抗氧化活性研究

本文研究了碱性蛋白酶最佳酶解条件,确定了碱性蛋白酶水解牦牛乳酪蛋白制备抗氧化肽的最佳水解条件,通过体外消化试验检测了水解产物的抗氧化活性变化。碱性蛋白酶的最佳酶解为温度50℃和最适pH值7.5;碱性蛋白酶添加量2%、温度55℃、pH值7.5和反应时间2h,水解产物抗氧化活性最高,清除DPPH能力为55.75%。经过胃蛋白酶和胰蛋白酶体外消化试验,水解产物抗氧化活性减弱,其中胰蛋白酶对抗氧化活性影响最大,胃蛋白酶和胰蛋白酶分别消化1h后,水解产物清除DPPH能力降为30.36%。     

Protamex酶解马铃薯蛋白粉制备抗氧化肽工艺优化

以马铃薯蛋白粉为原料,利用Protamex复合蛋白酶对其进行酶解制备抗氧化肽。以总抗氧化力为指标,采用Box-Behnken响应面设计对酶解工艺进行优化。结果表明,最佳酶解条件:底物质量浓度5%,加酶量4 000 Ug,酶解时间165 min,在此优化条件下得到的酶解产物的总抗氧化力为0.751 mmolL,回归得出的模型预测效果较好。      

猪骨蛋白的碱性蛋白酶酶解工艺及其产物抗氧化活性研究

在单因素试验的基础上,采用Box-Behnken设计对碱性蛋白酶酶解猪骨蛋白工艺中的酶的浓度、温度和pH值3因素的最优化组合进行了定量研究,建立并分析了各因素与水解度关系的数学模型;同时研究了酶解物对羟基自由基的清除效果。结果表明:最佳的酶解工艺参数为酶的浓度4%、酶解温度50.6℃和pH值8.1,经试验验证在此条件下水解度为32.8%,与理论计算值33.2%基本一致,说明回归模型能较好地预测碱性蛋白酶酶解猪骨蛋白的水解度;当酶解物浓度在133～4000μg/mL范围内,其对羟基自由基的清除率为21.84%～88.16%,且都存在明显的量效关系。     

大豆肽-钙螯合物制备条件优化与质量评价

采用碱性蛋白酶对大豆脱脂豆粕进行酶解,探究大豆肽-钙螯合物的最佳制备工艺参数,并对大豆肽-钙螯合物的性质进行分析。以钙结合量作为指标,研究肽钙比、反应温度、反应时间和pH值对钙结合量的影响,并通过Box-Benhnken中心组合试验以及响应面分析法对螯合工艺进行优化。结果表明,最佳螯合工艺为:肽钙比1. 6、反应温度38℃、反应时间44 min、pH值6. 6,在此条件下制得的大豆肽-钙螯合物的钙结合量为78. 73 mg/g。经试验,测得大豆肽-钙螯合物的溶解度为98. 59%,分子量大于5 000 Da的大豆肽-钙螯合物占1. 76%,分子量小于5 000 Da的占98. 24%,分子量小于1 000 Da的大豆肽-钙螯合物占80. 24%,其中分子量180～500 Da的大豆肽-钙螯合物占比最大。本研究可为新型大豆营养保健产品及合成新型补钙制剂的研发提供新方法、新思路。     

葡萄籽蛋白的中性蛋白酶酶解工艺及其产物抗氧化活性研究

首先优化葡萄籽蛋白的中性蛋白酶酶解工艺参数,然后研究其酶解物的抗氧化活性。结果表明:最佳工艺条件为酶解时间2.9h、pH值6.6和酶解温度45.3℃,此时水解度为18.44%。葡萄籽蛋白中性蛋白酶酶解物在104～520μg/mL和166.6～833μg/mL范围内,其对DPPH自由基和羟基自由基的清除率分别为24.34%～38.02%和27.72%～81.19%;且都存在明显的量效关系。     

Overland water and salt flows in a set of rice paddies

Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m⁻¹) and an infiltration rate of 5.8 mm day⁻¹. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day⁻¹), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day⁻¹ was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.     

农村剩余劳动力就业问题的探讨

论述了我国农村剩余劳动力就业的意义，并针对我国农村剩余劳动力的现状，提出多渠道促进农村剩余劳动力就业的途径和办法。     

车用发动机润滑油失效规律与更换周期研究

研究在正常使用条件下１０Ｗ／３０－ＱＣ级润滑油用于某型车用发动机时所表现的失效规律,确认期服从两参数Ｗｅｉｂｕｌｌ分布,并给出分布的尺度参数η和形状参数ｍ之最佳线性无偏估计（ＢＬＵＥ）同时,还为定量分析,计算车用发动机润滑油的使用可靠性和合理确定其更换周期提供了一套可供借鉴的方法,并给出了具体的计算实例。     

瓦房店市水果生产标准化发展研究

瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。     

金谷子耐旱TG118引种试种及推广应用

对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。     

对《种子法》存在问题的探讨

《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。     

乡（镇）农业技术推广体系存在的问题及对策

乡（镇）农技推广体系是农业发展的关键。介绍朝阳市农业技术推广体系的现状,针对目前体制及运行机制、服务手段等方面存在的问题,提出适合朝阳市乡（镇）农技推广体系改革与发展的对策,以期对全省农技推广体系改革和发展起到一些借鉴作用。     

草莓的采收与贮藏

草莓果味酸甜爽口,营养价值高,为人们所喜爱的应市鲜果之一。由于草莓易受损伤和微生物侵染,因此其采收、贮藏过程极为重要。介绍草莓采收过程中的注意事项以及11种贮藏保鲜技术的实施步骤和操作方法,推介9种加工方式,为草莓产业化提供技术支持。     

Review of the Egyptian experience in implementing land drainage projects

About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.     

和谐社会理论建设的几点哲学思考

在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。