基于沼渣原料的高温高湿杀菌耦合热风干燥生产牛床垫料工艺参数研究

为探究以沼渣为原料,高温高湿杀菌和热风干燥结合生产牛床垫料的最优参数,文章首先采用正交实验对高温高湿杀菌阶段的参数(干燥温度、干燥湿度、物料厚度)进行了优化,并通过单因素试验确定了较优的干燥时长;采用响应面分析方法获得了热风干燥阶段最优参数(干燥温度、物料厚度、干燥时长),研究发现70℃,60％ RH,5 cm,2h作...     

餐厨垃圾、农业废弃物与奶牛粪便好氧发酵过程质量变化研究

以奶牛粪便为主要原料,以餐厨垃圾、玉米秸秆、蔬菜废弃物、蔬菜废弃物发酵尾料为辅料进行混合配比,通过自制发酵反应器进行强制通风好氧发酵,比较不同辅料与奶牛粪便发酵过程质量变化和堆肥效果的影响。试验共设6个处理（CK：牛粪;T1：牛粪+尾料;T2：牛粪+餐厨垃圾;T3：牛粪+餐厨垃圾+尾料;T4：牛粪+蔬菜废弃物;T5：牛粪+玉米秸秆）。结果表明：CK、T1、T4、T5的55℃以上高温期持续时间均达到5天,符合好氧发酵对高温期天数的要求,而T2、T3均不足5天,其中T3未达到55℃以上高温,高温期平均温度T5最高为62.8℃。发酵结束后,物料含水率损失率在27.08%-47.39%,T4处理损失率最高;pH范围在8.15-8.84,仅CK和T3处理的pH＜8.5;有机质损失率在9.19%-17.28%,以T5为最高;各处理的总氮、总磷、总钾均高于初始含量,T1和T4能够显著提升物料的总养分;重金属As、Pb、发酵后的Cd含量低于发酵前,而Hg、Cr含量则相反,尤其是纯牛粪发酵后Cr含量超标应引起重视。奶牛粪便与玉米秸秆/蔬菜废弃物混合发酵更能够有效提升堆肥品质。     

木醋液对牛粪堆肥理化性质的影响

以牛粪为堆肥原料,研究不同浓度木醋液对牛粪堆肥理化性质的影响。试验采用好氧人工翻堆方式进行。试验共设4个处理,浓度分别为0.2%、0.5%、0.8%的木醋液处理和不添加木醋液的对照处理。通过试验分析温度、含水率、EC、pH值、铵态氮和硝态氮含量等指标随堆肥发酵时间变化的特征。结果表明:各处理组在堆肥发酵过程中pH均在适宜微生物生长的范围内,含水率都保持在55%以上;EC都呈先上升后下降的趋势;添加不同浓度木醋液处理与对照处理相比,都显著提高铵态氮硝态氮含量,从而有效减少堆肥发酵过程中氨气挥发和氮素损失,其中浓度为0.5%木醋液处理效果最好,与对照相比,肥堆升温快,进入高温所需时间短,高温持续时间长,在整个堆肥发酵过程中含水率一直保持在60%~70%之间,发酵结束时物料电导率较低,堆料腐熟快,有利于加快堆肥发酵进程。     

玉米果穗深床层热风干燥特性试验

为了提高玉米果穗干燥均匀性和干燥效率,降低干燥品质损失,通过研制玉米果穗深床层干燥试验台,并进行不同风速（0.5、1m/s）、热风温度（常温（即室温）,50、60、70℃）以及料层厚度（180、360、540、720mm）下玉米果穗干燥特性以及品质试验研究,确定最佳的玉米果穗深床层干燥工艺与参数。试验结果表明,提高热风温度和风速均会提高干燥速率,风速0.5m/s时,热风温度50、60、70℃条件下第1层的干燥时间分别为28、20、14h,而常温通风干燥下192h后含水率仅下降到20%,随着热风温度的降低,干燥时间显著延长;提高热风风速有利于提高干燥速率,第3、4层玉米果穗干燥速率受风速的影响大于第1、2层;随着料层的增加,各干燥条件下干燥速率显著降低,干燥时间延长;常温条件下果穗各料层长时间处于高湿环境,从而在玉米果穗高含水率阶段采用常温通风干燥方式容易造成内部高湿和发热现象;干燥过程中玉米籽粒含水率先下降,果穗芯轴的含水率高于籽粒。与对照组相比,各组干燥物料的亮度均下降,提高热风风速和温度会降低亮度;常温通风干燥玉米籽粒电导率最低,随着温度和风速的提高,电导率升高,表明籽粒内部结构破坏较大;干燥后玉米籽粒淀粉含量和可溶性糖含量均有所减小,其中70℃、0.5m/s条件下玉米淀粉含量最低,60℃和70℃、0.5m/s条件下玉米可溶性糖含量较低。根据研究结果,确定玉米果穗深床层干燥工艺为先热风干燥后常温通风干燥的方式,热风温度50℃或60℃、风速0.5m/s、通风管路单侧料层厚度为360mm为较优的果穗热风干燥工艺参数。     

基于遗传算法的苦瓜片真空冷冻干燥工艺优化

为提高苦瓜片干制品品质,应用真空冷冻干燥技术对新鲜苦瓜片进行干燥,以得到最佳工艺参数。采用响应面分析法设计四因素三水平试验,对苦瓜片试验指标（含水率和复水比）和干燥工艺参数（切片厚度、温度、绝对压强和干燥时间）建立二次多项式回归模型,并对模型的有效性及因素间的交互作用进行分析,利用Matlab中的遗传算法对结果进行综合优化。结果表明：建立的回归方程拟合度较好,模型显著,所得工艺参数合理可用。苦瓜片真空冷冻干燥的最佳工艺参数为：切片厚度为4mm,隔板温度为46℃,绝对压强为73Pa,干燥时间为8.7h。该条件下含水率为6.23%,复水比为11.75。     

木醋液对牛粪好氧堆肥理化特性与育苗效果的影响

传统的牛粪好氧堆肥作为育苗基质利用,其育苗效果差,加入调理剂是改善育苗效果的重要手段。为研究木醋液对牛粪好氧堆肥物料理化特性及育苗效果的影响,以牛粪、小麦秸秆为原料,木醋液添加量为0、1%、3%、5%,在自主设计的小试堆肥反应器中进行好氧堆肥试验。选取黄瓜为指示植物,使用堆肥腐熟料进行育苗试验。结果表明：随着木醋液添加量的升高,堆肥物料的含水率、总氮含量、总磷含量、K+含量及有机质降解率呈现上升趋势,pH值、电导率呈现下降趋势;低浓度（添加量1%）木醋液可促进纤维素、半纤维素的降解,发芽指数最高,为79.17%,且1%木醋液处理组的壮苗指数最高,为0.0449g,显著高于其他3组（P＜0.05）。     

巨菌草高温快速干燥设备设计与试验

为了解决巨菌草含水率高、不易贮藏,以及自然晾晒中人工劳动强度大、营养损失大的问题,设计了一套大型高秆禾草高温快速干燥设备。基于传热传质理论,进行了关键参数计算与关键部件的设计,通过力学分析与FLUENT流体仿真进行优化,并对控制单元进行了设计。以最终含水率、水活度、色泽度、粗蛋白含量、酸性洗涤纤维含量和中性洗涤纤维含量为评价指标,进行了设备的干燥试验,并与新鲜物料、自然晾晒干燥进行对比分析。结果表明:高温快速干燥后,巨菌草的最终含水率为(16±1.82)%,水活度为0.564 8,生产率为2.73 t/h;与新鲜物料相比,亮度值L和蓝黄值b均无显著性差异,红绿值a增加了1.43;粗蛋白含量与酸洗中洗纤维含量均无显著性变化,粗蛋白质量分数较新鲜物料下降0.6个百分点。与自然晾晒相比,高温快速干燥后巨菌草的粗蛋白质量分数增加了0.63个百分点,且具有较好的表观质量。试验结果表明,该套设备改善了干燥后巨菌草的表观质量和品质,满足了巨菌草干燥的要求。     

猕猴桃片旋转托盘式微波真空干燥特性分析

为研究猕猴桃片基于旋转托盘式微波真空干燥特性及品质优化工艺,探讨了不同功率密度（3.33、6.25、9.58W/g）、干燥温度（40、45、50、55℃）、腔室压力（5、10、15、20kPa）及切片厚度（3、6、9、12mm）对猕猴桃片干燥特性的影响,比较了旋转托盘式相对于传统水平转盘式微波真空装备的优势,并研究了不同模型拟合预测猕猴桃片水分比变化的准确性与适用性。结果表明：随着功率密度的降低和切片厚度的增大,物料干燥过程中存在更为明显的恒速段;当干基含水率降至1.3g/g左右时,干燥过程转入降速阶段。综合考虑感官评价及干燥时间可得,功率密度6.25W/g、干燥温度45℃、腔室压力5kPa、切片厚度6mm干燥条件下猕猴桃片干制品品质最佳。旋转托盘式微波真空干燥可大幅提升物料装载量,干燥均匀性较传统方式提升了16%,干燥平均能耗仅为后者的71.2%。通过模型预测值与试验实测值的比较,BP神经网络模型决定系数R2可达0.996,相比Weibull模型能更好地预测猕猴桃干燥过程的水分比变化规律。     

9ZS系列鸡粪(猪粪)干燥成套设备

９ＺＳ系列鸡粪（猪粪）干燥成套设备该设备的特点是；在工艺上采用高温快速分段干燥工艺，在结构上将搅拌预干和气流干燥相结合形成全密封结构，热源采用直火炉，较好地解决了粪便粘附结块、灭菌除臭等难题；可将含水率在７０％～８０％的湿粪便直接干燥到含水率１３％以...     

热力干燥中热湿不稳定物质质量的保护

生物物料和食品在热力干燥过程中的质量退化主要是由其热湿不稳定特性导致的。因此为保持干燥后产品的质量,常采用较温和的干燥条件,以及减少物料在高含水率阶段的干燥时间。为观察其对物料品质指标的影响,对面包酵母和清蛋白两种物质在不同的干燥条件下进行了热力干燥试验。结果显示：欲获得更好的热力干燥后产品品质,对热、湿耐受性不同的生物物质应采用不同的保护措施。     

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.     

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。     

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。     

A European irrigation map for spatially distributed agricultural modelling

We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.     

粉质仪和拉伸仪在面粉生产中的应用

在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。     

农村信息化服务的现状及建设措施

分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。     

车辆ABS控制算法的研究及探讨

对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。