稻谷烘干、除杂、加工一体化循环利用技术的应用与推广

中央储备粮庐江直属库地处长江中下游地区，全年平均气温在15．7℃～16．1℃，南北差异较小。年平均风速3．0m／s～3．4m／s，春季最大，为3．4ml／s～3．7m／s；秋季最小，为2．6m／s～3．2m／s。年降水量在1000mm～1158mm。相对湿度平均为75％。本地区夏季干热，6、7、8月平均气温30℃，     

高压静电场对陈年棉种发芽及活力的影响

本试验研究了在3200 kV/m适宜高压静电场中,0 s、10 s、20 s、40 s、60 s、80 s不同处理时间对棉花陈年半毛籽发芽及活力的影响。结果表明:在高压静电场中,在0～60 s内,随着处理时间的增加,陈年棉种的发芽势、发芽率、简化活力指数以及脱氢酶的活性提高显著,绝对电导率则呈现下降趋势,陈年棉种活力提高;在处理时间为60 s时处理效果达到最佳,其简化活力指数由最初的271.1升高至358.8;而随着处理时间的继续增加,处理效果逐渐减弱。     

气相色谱法测定粮食中有机磷农药残留量的方法研究

充实优化了以气相色谱法测定粮食中有机磷含量的方法。采用FPD检测器,0.32mm×0.25μm×30 m HP-5毛细管色谱柱,进样口温度为240℃,检测器温度为245℃,氢气流速和空气流速均是65 mL/min。程序升温条件为70℃(0 min 15℃/min)、150℃(2min 3℃/min)、185℃(2min 2℃/min)、210℃(2min),能够在35.5min内完成分析。标准曲线线性范围为0.1μg/mL~1μg/mL。该法可用于对多种有机磷农药残留同时进行测定,测试时间更短,方法更简便。     

沼液在水稻生产上的应用初探

正常生产的沼气池内，有机物经发酵利用后遗留下来的液体部份，称沼液，是一种很好的速效复合有机肥。据四｝【I省农科院测定，沼液含全氮0．03％～0．05％、全磷0．02％～0．06、全钾0．05％～0．1％，还含有多种氨基酸和活性酶，具有提供植物生长养分和促进植物新陈代谢，刺激、调节植物生长发育，从而提高作物产量的作用。我县1994年引进该项技术在水稻上进行浸种和叶面喷施试验，获得成功，1995年示范面积674．ghm’。1996年扩大示范，面积1013．shin‘，平均667m‘增稻谷42kg，1997年继续扩大示范，面积达1445．96hm’，667m’增稻谷3…     

西瓜嫁接壮苗培植技术

1建造苗床 苗床应选择地势高燥、背风向阳的地块。苗床宽1．0～1．5m,深12cm,长10～15m。先将床内熟土取出,再将下层生土取出筑畦埂,然后将一半熟土与一半捣碎过筛的圈肥均匀混合,每立方土再加入0．5kg氮磷钾复合肥,     

无公害越夏番茄高产栽培管理技术

越夏番茄利用北方夏季昼夜温差大和温度相对较低的气候优势．对蔬菜淡季供应起到补充和调剂作用。越夏番茄生长的夏季高温多雨季节．是病虫害多发期。几年来,我们本着“防治系统化、质量绿色无害化”的原则．在上板城漫子沟建立了无公害蔬菜示范园区．园区内生产严格执行承德市地方技术标准《长货架番茄越夏栽培技术标准》,在栽培、病虫害防治中引进多项无公害技术。     

利用CFD模型研究苹果冷藏库内的空气流动

苹果冷藏库内的空气流动可调节库内环境,且气流速度对改善果实品质具有重要的作用,因此有必要研究苹果贮藏库内的空气流动特性。本研究采用CFD（Computational Fluid Dynamics）方法,运用大型计算流体动力学软件Fluent建立模型,以标准湍流模型对苹果冷藏库内的空气流动做三维模拟。模拟时以苹果堆码区作为多孔介质,研究库内堆码苹果时的空气流动状况,并对库内的空气流速进行试验测定和验证。结果表明,通过气流场模拟能较为直观地显示冷库内部的流场特征和流动状态,气流从风扇流出,在风机与货物堆码区形成明显的涡流;气流在货物堆码区分布较为均匀,靠近风机的货物堆码区气流速度均高于远离风机的货物堆码区气流速度。冷库流场的测量值与CFD模拟的结果进行对比,最大误差在10%以内,测量值和模拟值之间的相关系数在0.9以上,说明了CFD模拟的可靠性。该模拟结果可为商用苹果冷藏库的优化和库内环境调节提供一定的理论依据。     

浅谈仓门隔热密闭对储粮的影响

仓门是仓房的重要组成部分，是储粮出入仓的主要通道，同时也是储粮在进入正常保管后，外界因素影响储粮品质的一个突破口。我库从2000年起，对仓内各部位(特别是门口部位)的储粮品质变化进行了跟踪检查和对照，发现改善仓门的隔热、密闭性能，对于储粮的保管有着重要意义。     

1-MCP处理对不同产地酥梨低温贮后货架期防褐保鲜效应的研究

以山西太谷和运城地区的砀山酥梨为试材,研究不同浓度1-MCP处理的酥梨果实在（0±0．5）℃低温条件下长期贮藏后常温20℃货架9d期间的品质和果实虎皮病的变化规律。结果表明：1-MCP处理能极显著抑制（运城）和完全控制（太谷）酥梨果实贮藏后货架期间的虎皮病．保持果实良好的外观色泽和内在品质,明显降低酥梨果实的呼吸强度和乙烯释放量以及果皮和果肉组织的总酚含量和PPO活性。1-MCP处理可以作为控制砀山酥梨低温贮藏后货架期间果实组织褐变f尤其是虎皮病1和保持良好品质的主要技术措施,建议1-MCP适宜处理浓度为0．5～1．0μL／L。     

GPC-HPLC法测定茶叶中多菌灵和甲萘威农药残留量

采用高效液相色谱法测定茶叶中多菌灵和甲萘威农药残留。样品通过乙腈提取,凝胶色谱净化（GPC）,在线浓缩,采用Waters C18柱（3．0×250mm×5μm）,乙腈和水为流动相梯度洗脱,柱温30℃,流速0．5mL／min进行分离,PDA检测器进行检测,波长为285．2nm和220．3nm,进样量5μL。回收率为84．5％～103．296;RSD为3．296～4．596;检测限多菌灵为0．1μg／mL、甲萘威为0．03μg／mL。     

不同送风方式下樱桃压差预冷的数值模拟

预冷时间对樱桃的贮藏期有着重要的影响,故合适的压差预冷方式成为预冷的研究重点。本文建立了水平送风与垂直送风的樱桃压差预冷数学模型,分析了两种不同送风方式下不同风速下包装箱内部的压力损失、预冷时间、均匀程度的变化情况。模拟结果表明:樱桃的预冷时间随送风速度的增加而减小,压力损失随风速的增加而增大,两者与送风速度的拟合关系均为幂函数;同时樱桃的不均匀度也受送风速度的影响,两者呈正相关;在送风速度6～16 m/s范围内的垂直送风的不均匀度仅为水平送风的75%左右。综合预冷时间、压力损失和均匀程度可以得到水平送风与垂直送风的最佳送风风速分别为9.3 m/s与12.7 m/s,压力损失分别为94.8 Pa与87.9 Pa,预冷时间分别为48.10 min与45.89 min,不均匀度分别为0.412与0.330。即垂直送风的预冷方式在樱桃压差预冷方面有一定的优势。     

AN EXPERIMENTAL RESEARCH ON ENHANCEMENT OF HEAT TRANSFER OF FINNED TUBES IN REFRIGERANT HEAT EXCHANGER

In this paper,the comparative experimental research that air flows through theout-surface of a single row finned tubes is done in a drawing wind tunnel and the three differnetshapes of rectangluar finned tubes are compared with a plain finned tube that is usually used in therefrigerant heat exchanger, the useful results are obtained. The results show that,in the range ofwind velocity flowing through the marrowest area, W_(max)=2.5m/s to 8.5m/s,the average convec-tion heat transfer coefficient of the two-side V-groove finned tube is higher than that of rectangluarplain finned tube,It is a new type finned tube that has good heat transfer performance and it isworth poplarlzing.     

Experimental investigation of electrothermal defrost tubes’ arrangement on heat transfer and flow resistance characteristics of evaporator

The paper presents new arrangement types of electrothermal defrost tubes and manufactures four evaporator samples. Through a wind tunnel refrigeration experimental test-bed, relatively experiments for every sample are carried to study heat transfer and flow resistances characteristics of evaporator. The experiment results show that in experimental face velocity range from 1.5 m/s to 4.3 m/s compared with flat-fin evaporator, the unit area of cooling capacity of DK-8 evaporator increased 28.1% to 36.2%, the fin surface coefficient of heat transfer raises 79.2% to 83.5%, the compressor COP (Coefficient of Performance) improves 38.2% to 46.9%, and the air side flow resistance decreases 5.29% to 18.3% in the same experimental condition and geometric size. The increase amplitude of COP is obviously higher than air side flow resistance. The experimental investigation results prove that it is completely feasible optimized combing defrost design with heat transfer enhancement design.     

Discussion about Saving Energy in Refrigeratory

Food refrigeration is regarded as a high energy consuming trade. Under the long period system of state operated enterprise,there are many phenomenons of ignoring energy management and wasting energy. Energy consuming is not very clear for production.Consuming in our country is far more than the international standard and there is a distance between the middle_westland and the eastland. As a enterprise that faces the international market,it is important for it to strength the management so that the cost can be reduced. Considering those phenomenons of ignoring energy management and wasting energy in refrigeratory at present, some measures such as improved the unreasonable operation process, strengthening the energy management and automation to realize automatizing operation are improved to reduce the cost for refrigeratory trades.     

农产品空气能热泵烘房温度场的数值模拟与验证

农产品热泵烘房温度场均匀性是影响农产品干燥品质的重要因素。本文选用5HGR-35型农产品热泵烘房,通过交互式CAD/CAM系统(UG)软件建立热泵烘房3D模型,运用理论分析与计算流体动力学(Computational fluid dynamics,CFD)模拟相结合的方法,研究其内部温度场分布情况,对现有结构烘房的温度场建模模拟,分析模拟结果并对现有结构进行优化。通过模拟得出结论:送风速度越大,烘房内热空气更新越快,换热效果越好。综合温度场分布以及农产品烘干要求,烘房内合理的送风速度为11 m/s左右;在11 m/s风速下,烘房空载时在15 min左右达到设定温度(65℃);小推车设计高度加大300~310 mm烘房内部温度场更均匀;烘房顶部均匀加入3块长×宽×高=2900 mm×20 mm×300 mm的挡板,可以使烘房内部温度场更均匀;小推车与烘房之间及相互之间保持30 mm左右间隙摆放更有利于烘房内部温度场的分布;验证试验中,模拟温度与实测温度吻合性良好。上述结论对烘房的进一步优化设计具有一定的指导意义。     

Model of Critical Velocity for Fire Ventilation in Horizontal Tunnels

1/20 scale model test and full scale field test were carried out to study the critical velocity for fire ventilation in horizontal tunnels. Combined with the test results, small scale test results by Jae and full scale test and simulation by Hu, a semi empirical model was developed to predict the longitudinal critical velocity for tunnel fire ventilation. Compared with the predictions of the proposed model and other models using air as fire source, it was found that the predictions by Wu and Barker was underestimates.     

Numerical Simulation of Natural Ventilation and Thermal Environment in Industrial Plant with Heat Source

Numerical simulation of typical industrial plant was conducted by computational fluid dynamics (CFD) method. The influences of distances between fresh air inlet and ground on thermal environment and distribution of pollutant concentration in working zone were discussed when the heat source intensity and pollutant source were fixed. The main features of industrial plant with heat source were analyzed. The air velocity in working zone and the radiation between the wall surfaces should be considered for comprehensive evaluation of the thermal environment of industrial plant. Heat stress index, HSI, was introduced as thermal index to evaluate the thermal environment. Results showed that lifted fresh air inlet was not only helpful to increase the ventilation rate and the air velocity which improve the thermal environment in working zone, but also to decrease the mean pollutant emission concentration in the plant. When the distances between fresh air inlet and ground increased, the ventilation rate and the air velocity in working zone increased and the HIS and pollutant concentration decreased. When the distances between fresh air inlet and ground exceeded 1.2 m, the ventilation rate and the air velocity in working zone tended to be constant.     

苹果片气体射流冲击干燥工艺的优化

采用一种新型的气体射流冲击干燥技术,对切片厚度6～8mm的苹果片进行了干燥试验研究。在喷嘴直径为16mm,喷嘴气流速度为16.8m/s的条件下,得出苹果片气体射流冲击干燥处理的最佳工艺参数为:喷嘴出口气体温度70℃,喷嘴与苹果片最佳距离120mm,干燥盒宽度为200mm,物料堆积高度为35mm。     

张家口地区风特征分析

为了揭示张家口地区风向风速时空分布特征及主要变化趋势,为该地区合理利用风资源、减轻风灾提供参考,利用1960—2013年张家口地区14个气象站风速风向观测资料,借助数理统计、线性拟合、气候倾向率等方法,对该区域的风特征进行了统计分析。结果表明,张家口地区年均风速坝上地区为3.6~4.1m/s,大于坝下地区的1.8~3.0m/s。年均风速变化总体呈减小趋势,54年间坝上与坝下地区分别减小了2.21m/s与0.92m/s,最大减小幅度均出现在20世纪70年代。年均风速呈“春季大、夏季小”的分布类型,平均风速最大、最小值分别出现在4月和8月。年均风速冬季减小速率最大,夏季最小。风速日变化坝上地区13—15时、坝下地区15时左右达到最大,凌晨5—7时风速最小,一天中平均风速上午的增长率与午后的下降率,坝上地区均大于坝下地区。坝上四县年均大风日数为48.5天/县,坝下为31.8天/县,大风日高值时段发生在1963—1974年间,坝上与坝下地区大风日数分别以9.4d/10a与7.1d/10a的速率减少。张家口地区全年以NW、偏北和偏西风向为主,市区、各县春季和冬季主导风向一致,夏季和秋季主导风向一致;进入夏季,随着暖湿气流的增强,张家口市偏南和偏东风出现频率有所增加。     

不同风速对温室厚皮甜瓜容器苗性状的影响

为了明确增加温室空气流动来培育厚皮甜瓜壮苗的实际效果和适宜的风速。本研究以不补风（V0）为对照,比较了风速分别为V1(0.1m/s)、V2(0.5m/s)、V3(0.9m/s)的机械补风处理对“伊丽莎白”厚皮甜瓜容器苗一些性状的影响。结果表明：补风处理后,茎粗、叶片厚度、全株干质量、子叶的叶绿素b含量增加,株高减小,其中后4个指标随着风速的增加变化越明显;与V0处理相比,V2和V3处理后,壮苗指数明显增大,其中V3处理后,根冠比明显增大,但真叶光合速率和叶绿素含量下降,而V2处理后,真叶数、根粗度增加,真叶光合速率和叶绿素含量上升。可见,增加空气流动明显提高了厚皮甜瓜容器苗质量,其中,0.5m/s的风速适宜在生产上使用。