Analysis of the Temperature Limit of Dynamic Water Intake of Open loop Surface Water Source Heat Pump Systems

Energy consumption of water intake is one of the key factors for energy saving in the application of the open loop surface water heat pump system. An energy efficiency ratio coupling model for open loop surface water source heat pump systems was established on the basis of the energy consumption model for the water intake and the heat pump units. According to energy saving rate and regulation of energy consumption of water intake, dynamic temperature limits of water intake in different water supply temperature of cooling tower and different pump head were proposed so as to find a calculation method of temperature limits of water intake of open loop surface water heat pumps. Moreover, the energy saving rate of surface water source heat pump systems compared with traditional air conditioning systems under various condition was also calculated.     

Mathematical Model and Operation Analysis of Semi-submerged Rotary Orifice Sewage Source Heat Pump Intake Machine

To solve the flow instability and adjustment difficulty of filtering dirt-removing device in the sewage source heat pump system, which affect the efficiency of heat exchanger, semi-flooded rotary orifice sewage auto-strainer was generated. According to establishing the mathematical model, the effect is analysed of pollutant concentration and liquid level height of sewage and rotation period of orifice plate to filtered flow rate, filtered load and filtering surface block coefficient. The result shows that: in the certain condition of sewage liquid level height and orifice plate rotation period, the increase of sewage will decrease the filtered flow rate of orifice plate, and increase filtering surface block coefficient; The effect of pollutant concentration change in the sewage to orifice plate filtered flow rate could be adjusted by regulating the sewage liquid level height and orifice plate rotation period, and the moderating effect of orifice plate rotation period is better than that of sewage liquid level height.     

Architecture Water-saving Design and Building Technique of Sponge Yard

The reclaimed water that we can use in daily life accounts for as much as 35 %,but we do not give it enough concern.The authors focus on the design methods and approaches of green buildings,which refer to water saving and environmental protection.In this paper,the authors illustrate the generating channels of reclaimed water in architecture design:rainwater collection integration design,sewage zero discharge of reclaimed water reused by biological technology,and sponge yard,thereby protecting environment.     

Study on the Innovative Rural Domestic Sewage Processing Technique

On the basis of analyzing domestic sewage features in rural China and also previous experience in sewage processing, a high-efficiency and low-cost technique for the rural domestic sewage processing was proposed, that is, "new bio-trickling filter + ecological concrete tank". Such an innovative technique is fit for national conditions of China, and worth to be popularized in rural China. The study also provides a referential support for other researches.     

滴灌玉米临界氮稀释曲线与氮素营养诊断研究

旨在建立宁夏引黄灌区滴灌玉米临界氮稀释曲线模型,探讨氮营养指数(NNI)用于实时诊断和评价玉米氮素营养状况的可行性,为实现滴灌玉米合理施用氮肥提供理论依据。以天赐19为试验材料,采用滴灌水肥一体化技术,设6个氮肥水平,利用2年定位试验构建并验证了临界氮稀释曲线模型。结果表明:(1)在一定范围内,滴灌玉米干物质积累量随施氮水平的提高而增加,根据方差分析结果,将玉米各生育时期的地上部生物量分为限氮和非限氮2类;(2)滴灌玉米植株氮浓度均随着施氮量的增加而提高,但随生育期的推进和地上部干物质量的增加,玉米植株氮浓度均呈下降趋势;(3)滴灌玉米临界氮浓度(Nc)、最大氮浓度(Nmax)和最小氮浓度(Nmin)稀释模型与地上部干物质累积量之间均呈现幂函数关系,其决定系数R2分别为0.982、0.907、0.918,利用均方根误差(RMSE)和标准化均方根误差(n–RMSE)的验证表明,该模型稳定性好,误差范围小;(4)氮素营养指数模型(NNI)可衡量滴灌玉米氮素营养状况,滴灌水肥一体化条件下,宁夏引黄灌区玉米以270kghm–2为最佳施氮量;(5)根据模型推算,NNI与相对吸氮量(RNupt)、相对地上部生物量(RDW)和相对产量(RY)均极显著相关。本研究所建立的滴灌玉米临界氮稀释曲线模型和氮营养指数模型,能够精准地预测水肥一体化条件下玉米小喇叭口期至成熟期的氮素营养状况,为优化玉米的氮素管理提供指导。     

绿茶栗香的形成及工艺研究进展

为研究绿茶栗香形成的干燥工艺及机理,笔者综述了近30年来国内外的香气及栗香相关研究,发现香气的研究较多而栗香的研究却少有提及。栗香香型虽已做出细分并探究出其关键组分,但仅在香气理论上猜测其形成机理,尚未基于加工工艺探究其具体机理。此外,栗香的影响因素并未做深入探究,仅推测出杀青、干燥工艺是栗香形成的关键因素,今后还需基于干燥工艺及参数等方面进行系统性研究。本论文归纳了栗香的相关文献报道,探讨了栗香形成的关键工艺,并着重分析了干燥工艺对栗香形成的影响,以期为栗香绿茶的定向加工提供理论依据。     

肉味香精加工技术研究与应用进展

肉味香精对改善食品风味和改良食品品质至关重要。现代食品加工高新技术对肉味香精产业的发展起着非常重要的作用,直接决定了产品质量优劣与产品的竞争优势。概述了肉味香精生产过程中常用的现代食品加工高新技术,如酶解技术、热反应技术、干燥浓缩技术、超临界萃取技术及微胶囊技术等,旨在为肉味香精的研究提供理论基础。     

农村生活污水分散式处理研究现状及技术探讨

分散式污水处理研究已经成为一种新的理念,其具有投资少、简单实用、管理方便、效率高、运行成本低等诸多优点,适合于中国农村生活污水处理。污水处理工艺技术的选择直接关系到污水处理效果及当地的环境卫生。本文综述了国内外农村分散式生活污水处理研究现状,对人工湿地、稳定塘、生物滤池、生态浮岛、厌氧生物处理工艺等主要分散式污水处理技术进行了探讨,并对常用的几种分散式污水处理技术进行了分类和比较。本文认为分散式生活污水处理组合工艺具有更强的适用性和应用性,是解决分散式生活污水处理难题的重要途径。     

Discussion of the Application and Foreground of Falling Water Aeration with the Process of Sewage Treatment

The engineering design of sewage treatment plant for the Chongqing city, P. R. China is analyzed in this paper. Considering the situation of China and other projects, the characteristics of falling water reactor for the environment protection project and economy of investment is introduced ; the application and foreground of falling water aeration in the process of sewage treatment is discussed, such as Oxidation - ditch, SBR, and so on. The conclusion indicated that the falling water aeration can be designed and used as an independent aeration, and, it is an upgraded technology of sewage treatment which is adaptive for city water environment control in middle and small towns in China. The falling water aeration may reduce running cost of the sewage treatment plant, is adaptive for foothill and the mountainous areas, and reduces project investment and environments damage.     

产业整合视角的农户行为研究——来自668个蔬菜种植户的实证

研究针对农户面临多种蔬菜产业整合模式的选择问题,基于交易成本理论,分析农户选择不同蔬菜产业整合模式的影响因素。通过构建农户基本生产经营特征、三大成本（抗风险、执行、谈判）评价指标,采用多元Logistic 模型进行影响因素分析。结果表明：批发市场模式仍然是目前最主要的蔬菜产业整合模式;农户基本生产经营的特征不同程度地影响着其对各种蔬菜产业整合模式的选择;其中最关键的影响因素是交易成本,但抗风险成本、执行成本和谈判成本对不同蔬菜产业整合模式的影响力存在很大的差异。该研究为政府在蔬菜产业整合方面制定政策提供有效依据。     

高寒地区土地渗滤技术处理生活污水的研究

为解决高寒地区农牧民定居点生活污水处理存在水质浓度低、运行费用高和无专业运营管理人员等问题,笔者拟采用土地渗滤系统进行高寒地区农牧民定居点生活污水处理试验,分析不同条件时的去除效率,确定最佳工艺运行参数。试验结果表明,高寒地区地下渗滤系统最佳工艺参数：填料配比为1:2,表层土厚度为15 cm,水力负荷为7 cm/d。地下渗滤系统对生活污水中的污染物具有较好的去除效率,出水能够达到城镇污水排放一级A标准。     

剁椒低盐加工技术研究进展

低盐加工技术不仅可以避免剁椒生产过程中的高盐污水处理问题、降低产品品质损失，也有利于减少消费者钠盐摄入，是剁椒产业的未来发展趋势。调查了目前市售剁椒的产品情况，并主要从食盐功能代偿辅料的加入，精准调控发酵过程，环保高效的污水处理手段与高盐卤水再利用几个方面综述了剁椒低盐加工技术研究进展，以供相关研究人员参考。     

PROBABILISTIC EVALUATION FOR STEEL FRAME COLUMNS OF TALL BUILDINGS

Based on properties of parameters and test data of dom-estic steel,this paper analyses the reliability and partial coefficient forresistance of steel frame columns of tall builings.The result may serveas a scientific basis.It is not only for domestic steel instead of importedsteel in building tall steel structures,but also for compiling concerendstandards.     

Fire-resistance performance of high-strength-steel H shaped columns under the axial compression

In order to investigate the fire-resistance performance of high-strength-steel column,this paper deduces the critical stress of high-strength-steel columns under the axial compression at high temperature by introducing the mechanical properties of high-strength-steel at high temperature.Moreover,coefficients of overall stability and critical temperature for high-strength-steel column under the axial compression are obtained which can provide a reference for design.The comparison of overall stability coefficient and critical temperature between high-strength-steel and normal steel is made.The results show that the overall stability coefficient and critical temperature for normal steel is not applicable for high-strength-steel,and the overall stability coefficient for high-strength-steel is smaller than that for normal steel.The paper uses the finite element analysis to validate the overall stability coefficient,and good match was found between them.     

Disposal of Rural Domestic Sewage in Ecological Wetland System

Pollution brought by rural domestic sewage has become increasingly serious, so it is imperative to fi gure out economical and efficient solutions. On the basis of comparison between rural domestic sewage treatment means in China and abroad, actual conditions of countryside, current situation and features of domestic sewage, this paper adopted the compound ecological wetland system consisting of anaerobic and aerobic units, ecological floating bed and artifi cial wetland, so as to remove nitrogen and phosphorus efficiently, achieve the goal of low operation and construction cost and less land use.     

Analysis of Stress Intensity Factors of Cracking Tip in Asphalt Overlay

Stress intensity factor at crack tip is the basis of studying the law of crack propagating, which indicates the critical degree of tending to crack at crack tip according to numerical style. The finite element method is used to analyze the crack stress intensity factors of overlay, the influence of parameters like overlay thickness, modulus, preliminary cracking length, temperature variation, and axes loading on crack intensity factors are studied, it offers theoretical basis for anti - cracking design methods of asphalt overlays.     

云南不同产地三七的重金属吸收累积特征研究

[目的]三七Panax notoginseng (Burk.) F. H. Chen是我国传统珍贵中草药植物,其在云南种植区域不断北移和扩大,重金属污染问题已引起广泛关注,但相关研究却非常有限。[方法]本研究采集了分布于云南三州七县27个三七样品,并采用湿法消解前处理方法,电感耦合等离子体质谱仪( ICP－MS) 测定其4种重金属元素Pb、Cd、As、Cu 的含量,揭示云南不同产地三七植物体内重金属的吸收富集特征及转运规律,并对不同产地三七的食用安全性进行人体健康评估。[结果]结果表明,参照《药用植物及制剂外经贸绿色行业标准》,三七块根中Pb、Cd、As、Cu的超标率为0%、62.96%、37.04%和0%,对应叶片中的超标率分别为37.04%、33.33%、48.15%、3.70%,应加强Cd、As的安全性关注。三七块根中Cd的富集系数最大,As和Cu相近,Pb最小。叶片中Pb、As、Cu富集系数变化较小,与三七块根相似,而Cd不同产地富集系数变异较大,最大的建水是最小的师宗的8.3倍。聚类分析表明不同地区的不同重金属的污染程度差异较大。不同产地三七Pb、Cd、Cr、Cu 对人体的摄入风险贡献依次为4.91%～10.00%、3.83～10.50%、7.34～23.28%、0.40～0.61%,所占比例较小。[结论]云南部分三七存在一定的重金属污染风险,本研究可为三七药材的规范化种植,安全评价及三七安全质量控制技术提供理论依据。     

珠美海棠试管苗移栽前后气孔及根系状况的观察

珠美海棠(Malus Zumi)试管苗在试管内气孔全部开张,根系无根毛,移栽到土壤后,气孔逐渐关闭,根系正常发育,无主根,多水平根,地表毛根很多,因此适应在地下水位高的低洼地区生长.这一发现,为改进试管苗移栽技术提供了理论依据.     

作物高光效之管见

光合作用提供了作物产量形成的物质基础。目前作物的叶面积指数和经济系数已难以继续增加,若想进一步提高作物产量就必须提高生物量,提高作物光能利用率成为关键。作物高光效是一个内涵和外延非常广的概念,涉及作物生命活动的全过程,与众多学科相联系,不同学科有着不同的理解。作者根据现有的研究进展,结合从事作物生理、育种和栽培的实践,从光合作用的主要过程及关键调控位点、作物光能利用率、高光效作物的生理基础与形态特征和高光效作物的筛选与鉴定对"作物高光效"进行了概述,以期为今后的作物"高光效"研究提供一点有益的思考与借鉴。