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功能膜覆盖好氧堆肥过程氨气减排性能研究 总被引：8，自引：0，他引：8
畜禽粪便高温好氧堆肥过程中氨气的排放不仅污染环境,而且会降低有机肥氮素含量。因此,控制好氧堆肥过程中氨挥发是降低氮损失及减少堆肥周边环境恶臭的关键。为研究膜覆盖对畜禽粪便好氧堆肥过程氨气挥发的影响,以猪粪和小麦秸秆为试验原料,采用具有选择渗透性的Gore膜作为覆盖材料,在实验室好氧堆肥反应器系统中进行了为期27 d的好氧堆肥试验。试验设置覆膜组和对照组,采用开启1 h、关闭1 h间歇通风方式,通风速率为3 L/min,重点监测堆肥过程堆体温度、氧浓度和NH3排放速率等。研究表明:覆膜组比对照组高温期持续时间略长,更有利于杀死堆体有害病原菌;相比于对照组,覆膜组NH3排放量减少18.87%;相比于温度峰值出现的时间,两组试验NH3峰值出现时间均延后,且覆膜组延后时间更长。 相似文献
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好氧堆肥反应器试验系统设计与性能试验 总被引：5，自引：0，他引：5
针对现有好氧堆肥反应器试验系统体积小、实时监测和反馈控制功能单一等问题,在已有研究基础上设计了一种好氧堆肥反应器试验系统。根据静力学及热力学原理,对反应器试验系统关键功能单元进行了优化设计,开发了适用于该好氧堆肥反应器的自动控制系统,并对其进行了好氧堆肥性能测试试验。反应器体积为100 L,并具有实时监测不同梯度温、氧数据的功能,其反馈控制系统含有3套反馈控制方案。试验结果表明:好氧堆肥反应器试验系统内堆体上、中、下层温度高于50℃的时间分别为8.1 d、7.2 d和4.8 d;堆体各层最终pH值均小于8,种子发芽指数均大于85%,堆肥试验效果良好。 相似文献
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智能型规模化膜覆盖好氧堆肥系统设计与试验 总被引：3，自引：0，他引：3
设计了一种适用于规模化生产的节能环保智能型膜覆盖好氧堆肥系统,主要包括总控系统、风控系统、传感系统和覆膜系统。结合上述各系统的功能性需求,进行了系统整体性设计、功能模块独立设计选型,该系统可实现堆肥关键参数的高精度实时监测、通风供氧的灵活智能反馈控制、多设备无线通讯等功能。利用该系统进行规模化膜覆盖好氧堆肥性能试验,研究结果表明:整个堆肥过程高温时段满足粪便无害化处理需求,堆体氧浓度维持在适宜水平,覆膜工艺下可确保堆体发酵状况良好。从所监测的流量、频率、温度、压力、氧浓度等多元参数和总体性能来看,与传统技术模式相比,该系统智能化程度显著提升,生产能耗和气体产排显著降低。 相似文献
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集约化养殖场奶牛粪集中产出量大,资源化利用前贮存过程因局部厌氧易产生氨气和温室气体等,造成氮素损失和环境污染。采用具有选择渗透性的功能膜作为覆盖材料同时耦合微好氧环境,对比分析未覆膜大气环境下贮存物料特性动态变化,探索微好氧耦合功能膜技术对奶牛粪稳定贮存和气体减排的可行性。以奶牛粪为原料,在智能型膜覆盖好氧堆肥反应器系统中进行为期30 d的贮存试验。试验设置覆膜组和对照组,采用反馈调节模式使反应器内氧气体积分数处于4%~6%的微好氧状态,监测分析贮存过程堆体理化、生物学指标的动态变化和主要气体排放规律。研究结果表明:微好氧耦合功能膜技术更有利于奶牛粪的稳定贮存,且与对照组相比,贮存过程排放至环境中的氨气量减少14.4%,总温室气体排放量减少25.58%,减排效果显著。 相似文献
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试验室好氧堆肥反应器系统性能试验 总被引：3，自引：0，他引：3
为探讨试验室自制强制通风好氧堆肥系统的保温性能和通风性能及其对好氧堆肥过程的作用效果,进行了不同初始质量和初始温度的热水保温试验,测定了系统保温性能参数以及不同流量下的通风性能,最后进行鲜猪粪麦秸混合好氧堆肥平行试验.结果显示:各反应器保温箱的保温性能没有显著性差异,保温性能参数UA值的标准差为0.02,最大相对标准偏差为4.93%;各反应器间通风系统性能差异不显著,当流量计设定流量分别为0.2、0.5、1.0、1.5和2.0 L/min时,各反应器通风管出口处的流速在同一设定流量下基本相等;好氧堆肥试验过程堆体温度经历了快速升温、保持一段时间的高温和温度缓慢下降3个阶段,各反应器堆体温度超过50℃的时间分别为5.3天、6.0天、5.1天和6.8天,符合国家标准;可挥发性固体降解率依次为18.1%、13.3%、15.8%和15.2%. 相似文献
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鸡粪沼渣联合好氧堆肥基质降解与气体排放研究 总被引：4，自引：0，他引：4
利用好氧堆肥反应器系统开展鸡粪沼渣联合好氧堆肥试验,进行物理、化学、生物学指标和甲烷(CH_4)、氨气(NH_3)及氧化亚氮(N_2O)等排放气体的多元动态表征,并开展主要排放气体与堆体氧浓度和温度相关性分析。研究结果表明,通过合理物料配比、适度供氧的联合好氧堆肥可更有效地实现鸡粪沼渣安全、优质资源化利用。鸡粪沼渣联合好氧堆肥过程中,物理、化学、生物学指标动态变化具有良好的动态对应关系,纤维素类物质的降解主要集中在反应中后期。堆肥过程中CH_4与堆体氧浓度和温度均呈现良好的负相关关系,NH_3和N_2O与温度均呈正相关关系;可通过控制堆体氧浓度和温度调控气体排放。综上,基于多元参数表征、相关性分析可为鸡粪沼渣联合好氧堆肥工艺优化提供理论和方法学支撑。 相似文献
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为实时获取规模化好氧堆肥过程关键数据,实现自动化控制、优化堆肥工艺、提升产品品质,在已有研究基础上,设计了一种集成度高、便携性好的适用于规模化好氧堆肥过程的温度和氧体积分数实时监测系统,该系统主要包括温度数据获取模块、氧体积分数数据获取模块、信号处理模块、数据显/存模块。并系统开展了实验室和实际规模化好氧堆肥性能试验和分析研究。其中,温度监测相对标准偏差均小于3.02%,响应时间均小于45 s;氧体积分数监测相对标准偏差均小于2.96%,响应时间均小于30 s。研究结果表明:该系统在精确性、稳定性和响应速率等方面均具有良好性能,可满足规模化好氧堆肥过程温度和氧体积分数空间数据实时监测以及科研需求。 相似文献
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Overland water and salt flows in a set of rice paddies 总被引：1，自引：0，他引：1
E. Playn O. Prez-Coveta A. Martínez-Cob J. Herrero P. García-Navarro B. Latorre P. Brufau J. Garcs 《Agricultural Water Management》2008,95(6):645-658
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. 相似文献
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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。 相似文献
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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。 相似文献
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对《种子法》存在问题的探讨 总被引：1，自引：0，他引：1
李鹏 《农业机械化与电气化》2011,(6):129-130
《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。 相似文献
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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. 相似文献
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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。 相似文献
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Gunter Wriedt Marijn van der Velde Alberto Aloe Fayçal Bouraoui 《Agricultural Water Management》2009,96(5):771-789
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. 相似文献
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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。 相似文献
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车辆ABS控制算法的研究及探讨 总被引：1，自引：0，他引：1
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。 相似文献