共查询到20条相似文献，搜索用时 31 毫秒
1.
In multistoried or the high-rise civil constructions the full-time machinery hot water circulation supply system design,whether the design parameters for the flow and the lift of circulating pump are appropriate or not,will be related to continuously,safe,stably running of the hot water supply system.This paper introduces parameter selections of hot water circulating pump both at home and abroad.Based on the difference of these selection means it analyzes the calculating means of the flow and the lift of circulating pump.Whether the circulator flow should join the additional circulating flow or not is the focal point in the argument.In China's present "Code for design of building water supply and drainage" the additional circulating flow is considered not flowing through the circulating pump,so in calculation the additional circulating flow does not contain the circulator flow.By analysis of the water distribution operating mode and various ring circuits difference,as well as considering that for the very small circulator flow it is more difficult to use the valve regulation and to achieve balance between various ring circuits resistance loss,inaccessible absolute circulation in the same regulation,short circuit and so on,the circulator flow should be the sum of circulating flow and additional circulating flow.To calculate lift head the additional circulating flow should be considered through the calculating loop. 相似文献
2.
In this paper, the factors influencing the foundation scheme of high-rise buildings are analyzed. In accordance with the complex hierarchical structure and the uncertainty of foundation scheme, a knowledge base of hierarchical structure is set up and an inexact reasoning is realized. Then, the expert system for high-rise buildings foundation scheme (TBFES) is built on the knowledge base with the expert system tool CLIPS. 相似文献
3.
The schemes of domestic water supply for a residential quarter of high-rise building are introduced.The energy consumptions of water supply schemes selected are compared and analyzed.The energy saving of the water supply schemes with water tank and variable velocity variable frequency pump are obtained.And demonstrated the domestic water supply system of combination the roof water tank and variable velocity variable frequency pump is good at energy saving.Furthermore,by the comparison of the investment and cost of these schemes in their lives,the best choice of domestic water supply system is gained. 相似文献
4.
There are numerous shear walls with flanges in the high-rise buildings in P.R.China.The shear strength formula for shear walls in Chinese design codes lacks experimental data,while test results in other nations lack aseismatic shear strength test results for shear walls with flanges under axial force.In this paper,we report low-cyclic reverse load test results of shear wall models with large dimensions,one shear wall having an I-shaped cross-section and two with a T-shaped cross-section.We discuss why the aseismatic shear walls of high-rise buildings with large height-to-length ratios have small shear span ratios.We assess the reliability of the shear strength formulary in the Chinese codes for design of shear wall using the international shear wall test results. 相似文献
5.
The high elevated water tank of high rise building is an important part in thedesign of water supply system and fire water system in highrise buildings .The discussionsare presented in this paper about the necessity of high elevated water tank installation,thevolume of the tank and its installation height. 相似文献
6.
酶法回收虾头和虾壳中的蛋白质 总被引：3，自引：0，他引：3
利用蛋白酶水解虾壳和虾头,以水解度(DH%)和TCA可溶性氮为指标并结合感观评价,研究了各种条件对水解效果的影响。通过比较不同蛋白酶的水解效果,发现碱性蛋白酶的水解效果最好,最适的水解条件为:碱性蛋白酶添加量4IU/g,自然pH值,水解温度60℃,水解时间5～7h,固液比1∶10,风味蛋白酶(添加量13～65IU/g),于水解2h后加入,在此条件下,水解度达到20.7%,TCA可溶性氮达到42.0mg/mL,水解液无苦味和腥味,风味良好。 相似文献
7.
To overcome the disadvantages of traditional galvanized pipe, new types of water supply piping materials have been developed. Comparison and classification are made based on their characteristics such as thermal stability, resistance to pressure, expansion coefficient and thermal conductivity, resistance to water hammer, cost and easiness of installation. Furthermore, the characteristics were discussed according to their locations in buildings: distribution main line in each pressure zone, branch pipe in water closet and the main line. Finally, the conclusion about the principles for pipe selection according to its location in buildings is given. 相似文献
8.
The building embodied stage is the LCA research focus due to large and intensive CO2 emissions. In order to establish the CO2 emissions calculating model during the embodied stage, CO2 emissions load in the process of building materials, equipments manufacturing, transporting and construction should be included. CO2 emissions during building embodied stage of 78 office buildings were analyzed by this model. On average, the amount of carbon emission during embodied stage is 326.75 kg/m 2. The carbon emission in per unit area increase with the growth of building height and that of super high-rise buildings is 1.5 times as much as multi-story buildings. Carbon emission of civil work accounted for about 75% of the total amount during embodied stage, and the carbon emissions of rebar, concrete, mortar and wall materials accounted for over 80% of the carbon emission of civil work. According to the statistic of prediction model dependent on building story and amount of building materials,the CO2 emissions during building embodied stage could be precisely predicted on basis of the independent variablesincluding concrete and wall materials respectively. 相似文献
9.
Rock masses have defects,such as joints and fractures, which are the main seepage passages.Joints and fractures often are treated as parallel plates with the seepage state kept steady and the ground stress constant. When changes take place in joints and fractures as a result of stress changes induced by excavation,joints or fractures may be wedge-shaped,and the distribution of piezometric head along the fracture will be nonlinear.A distribution function of piezometric head is suggested and compared with the results of previous research.The influence of this function on the calculation of the slope safety factor is investigated.The study shows that this function is reasonable. 相似文献
10.
The calculation of constant pressure values for relief valves in the fire suppression systems of high-rise buildings usually is based on the working pressure of pipe systems by experience.However,this method only is applied in the condition that the relief valves are installed on the effluent pipes of pumps.In order to confirm the proper constant pressure values of relief valves in fire suppression systems,a formula is deduced using hydraulics theory.The applications of the formula in fire suppression systems are also discussed.The constant pressure values for relief valves are directly related to three factors,namely,the flux and pressure of the fire pump,the located height of the relief valves,and the head loss of flux from the pump exit to the inlets of the relief valves.It is necessary to analyze the working condition of fire suppression systems and to be certain of the permissive pressure range for overpressure. 相似文献
11.
Based on GPS technology,this paper studies the dynamic characteristic under ambient excitation of major blocks of Chongqing University and analyze excitation data and verifies the excitation scheme.The result of research indicates that the building vibration frequency can be obtained accurately and quickly to monitor dynamic characteristic of buildings under ambient excitation with GPS.It provides reference for structural design of high-rise building and basis of correcting error of construction accurately. 相似文献
12.
《Journal of Landscape Research》2017,(4)
The life-cycle eco-footprint computing model of building projects was established in the study. It contained the eco-footprint in 4 aspects during the lifecycle: consumed energy, consumed resource, emitted carbon dioxide and produced solid waste. Space efficiency of life-cycle eco-footprint index was proposed and used to assess the eco-sustainability of building projects. Then, the eco-footprint and ecosustainability of 4 different structure types(brick-concrete bungalow, multi-storey brick-concrete, multistorey steel-concrete, high-rise steel-concrete) for residential building in severely cold areas were investigated. The results indicated that: 1) Compared with bungalow, high-rise building with relatively smaller shape coefficient and window-wall ratio had higher eco-sustainability; 2) For the buildings with the same storey, shape coefficient and window-wall ratio, steel-concrete building had higher eco-sustainability than brickconcrete building; 3) High-rise steel-concrete structure had the greatest eco-sustainability during the 4 different bui lding structures, so it was more suitable to promote. 相似文献
13.
Wang Dongyun Qu Zhenlin 《保鲜与加工》1989,(4)
In this paper,the acting characteristics and effect of ground water on the stability of construction site and foundations in investigation,design,construction and service of buildings and structures are presented.The main problems of ground water are discussed. 相似文献
14.
Water supply in small towns is one of the important components of the small towns' economy and society development.Based on the actual condition of water supply system,this paper analyzes the problems existed in water supply system of small towns,such as gradually polluted sources,imperfect water supply facilities,smaller scales,unreasonable quantity and so on.In addition,the corresponding measures are put forward to guarantee water supply system develop speed in small towns.Those countermeasures are launching sources protection work to guarantee the drinking water safety according to the character of the small town,then adopts reasonable water supply style,chooses economy water processing method,optimizes water network system construction;selects reasonable quantity consumption quota,and carries out gradually the regional water supply mode in conditional small towns. 相似文献
15.
结球莴苣品种比较试验研究 总被引：1，自引：1，他引：0
结球莴苣在高温环境下栽培,植株往往遭受伤害或生长不良,为给生产提供优质的结球莴苣品种,本文选取目前栽培中具有代表性的8个结球莴苣品种进行了春夏露地和秋冬日光温室栽培比较试验,并对其苗期性状、商品性状、营养成分、产量及抗性进行观察比较和分析。结果表明：栽培条件不同,结球莴苣的各项生理指标表现出不同程度的差异。幼苗期J42表现最好,J44次之。J42和J44两个品种的叶片性状指标最好,产量最大,且抗病,W64表现为感病,其余品种均为中等抗病品种,无严重感病现象。J42的综合营养品质最好,而8个品种口感和质地相似,都带有苦味,质地脆。总之,‘国王102’（J42）和‘早玉结球生菜’（J44）这两个品种产量高,性状好,品质优良,抗性强,应加以推广。 相似文献
16.
In this paper, the correlative factor of ecological sub-zone, especially the correlative requirement of water use is studied. The role of the specialty of water supply and drainage in an ecological sub-zone is defined. In the light of the knowledge of water supply and drainage specialty, a new design idea for design of outside drainage network in living sub-zone is introduced. There are a lot of suitable conditions of such design to meet the water demands of ecological sub-zone in Chongqing. 相似文献
17.
The pattern of supplying water of differing quality using sewage recycling,and its implementation as a strategy,are discussed through an analysis of the water shortage situation in the city of Shenzhen,P.R.China. Supplying Shenzhen with water of varying quality is proposed as a concept.The necessity and feasibility of such a water supply pattern are expounded.The pattern of water supply in Shenzhen city consists of a main water supply system and non-potable water supply system with sewage recycling.In addition,the proposal also includes using seawater and rainwater.The non-potable water supply system with sewage recycling would be used primarily in large industrial parks outside the special economic zone and in other areas around the parks.Supplying Shenzhen with water of differing qualities embodies the concepts of sewage reused as a resource and of the recycling economy.This proposal also satisfies the requirement for urban sustainable development. 相似文献
18.
Through comparison of four experiment methods, the basic properties of expanded metal mesh are studied on the mesh with special form of oblique wires and nodes. Moreover, the property index for design is obtained after analyzing the 4 experiment methods, which supply the experimental and theoretical basis for the application of this material to buildings. It is suggested that such specimen can be used as standard one for determining the property index. 相似文献
19.
Based on the investigation of energy consumption and air conditioning system working of 14 typical hotel buildings in Three Gorges Reservoir area cities, energy consumption characteristics of hotel buildings are analyzed. Then the use status of energy efficiency technologies of those hotel buildings is analyzed. Finally, effective energy conservation approaches for hotel buildings are brought forward and the energy-efficiency potential of variable water volume system is analyzed through testing. 相似文献
20.
加拿大早熟群体杂交选系对玉米丝黑穗病抗性评价 总被引：1，自引：1，他引：1
为了了解加拿大早熟玉米群体杂交选系对黑龙江省主要玉米病害之一丝黑穗病的抗性水平,从而为中国北方玉米抗病育种提供优质种质资源,以80份加拿大早熟玉米群体杂交选系为材料,在哈尔滨、密山两地分别采用人工接种技术评价其对玉米丝黑穗病的抗性。结果表明,80份加拿大玉米群体杂交选系中没有高抗材料,发现SW1284等14份抗病材料,SW1084等13份中抗材料,SW1236等35份感病材料,SW1175等18个高感材料,中抗以上材料占全部鉴定材料的33.8%;杂交选系与供体双亲平均发病率相关极显著,相关系数r=0.30（r0.01,78=0.281）。 相似文献