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1.
As a renovation envelope, the double-skin facade has the characteristics of environment-friendly function and unique aesthetic effect. In this paper, the history and evolution of the double-skin facade is retraced and analyzed. At the end, it is pointed out that the environmental thoughts and aesthetic exploration are the impetus of its evolution.  相似文献   

2.
The lighting for city night scenes became a hot spot of urban construction.It is quite necessary for building designers to understand the relationship between the facade fabric design and the facade lighting design of a building and know the design method as well.This paper analyses the relationship between the facade fabric design and the lighting design,and proposes the factors that should be considered in the facade fabric design process.  相似文献   

3.
Development of a city depends largely on its transportation, and road construction reveals development skeletons of the city. With the aggravation of city pollution, construction of ecological corridor has been put on the agenda of urban ecological construction, against this background, "2 rings and 17 radial lines" of Zhengzhou City were planned. This paper analyzed the plan from the perspectives of role of urban green corridor, planning principle, characteristic building and greening of building facade, and exploration of green corridors integrating pathways, bikeways, bus harbors and green island gas station.  相似文献   

4.
Architectural decoration is a key demonstration of architectural styles, and traditional Chinese architectural forms originating from diversified architectural decorative arts. This paper explored facade decorative art of traditional architecture from the perspectives of carving art decoration, roof type, stylobate and railing, window and door type, and ground pavement, and also elaborated artistic methods of different forms in each aspect. On the basis of investigating Shengjinta historic and archaistic block, the paper also introduced application of decorative arts, and provided references for applying facade decorative arts of traditional architecture in the future archaistic blocks.  相似文献   

5.
Monolayer cable net system for point - supported glass facade is a kind of flexible tension structures with relatively strong nonlinearity. Its stiffness greatly depends on the pretension in cables. Yet there are few literatures at present reported on its dynamic properties. The characteristic of modal analysis for flexible pre - stressed structures such as cable structures is expatiated herein. Corresponding program was developed to analyze two important factors such as pretension and geometric nonlinearity for dynamic behaviors of cable net herein. It is demonstrated that large errors are brought about by omitting nonlinearity. There exists apparent nonlinear relationship between vibration frequency and pretension in cables. The influence of pretension and geometric nonlinearity on the dynamic properties of cable net is in coordination with each other.  相似文献   

6.
村级服务站是农技推广体系在村级的延伸与发展,兼有经营性和公益性的双重功能,对于满足农民多元化的农技需求起到重要作用。为了改善村级服务站的运行效果,探索影响村级服务站服务功能发挥的因素,此文以石家庄为例,借助实地调查数据,对村级服务站运行中存在的问题及影响因素进行了调查分析。研究结果表明,村级服务站技术人员的自身素质和村级服务站硬件设施不完善是影响村级服务站运行效果的重要因素。  相似文献   

7.
薛建鹏 《中国农学通报》2005,21(12):455-455
社会服务功能是大学、也是大学科技园核心竞争力的重要组成部分。西北农林科技大学国家大学科技园在建设中,找准位置,不断强化公益性社会服务功能,以“五个结合”促进“三区并举”,取得了社会效益和经济效益的双赢,为我国农林类大学科技园的可持续发展开辟出了一条特色之路。  相似文献   

8.
RNA沉默(RNA silencing)是真核生物体内普遍保守的、发生在RNA水平的、基于核酸序列同源性相互作用的一种对基因表达的调控机制.通过设计反向重复构建在植物体内产生双链RNA来诱导RNA沉默的方法是一条非常有效的植物抗病毒和功能基因组研究途径.本研究通过两个病毒基因的反向重复构建发展了两种通过小型中间载体设计反向重复构建的方法.其共同特点是构建简易,操作方便,可为通过设计反向重复构建实现植物体内高效持久的RNA沉默提供方法上的参考,促进RNA沉默技术更加广泛深入地应用于植物抗病毒基因工程研究和植物功能基因组研究.  相似文献   

9.
This paper introduces the main structure and function,the theor-etical basis and the main features of the computer aided design software system QT-SCAD for the steel structure of tower crane.The QT-SCAD is suitable for allkinds of movable or fixable tower crane with level arm which rotates above thecrane body,and has single or double hanging points.It can be used for the stre-ngth,stiffness and stability analyses of the structure,the vibrative and dynamiccalculation of mechanisms and structure,and the optimal design of the structureof tower crane or its components.  相似文献   

10.
11.
Mountain landscape is a significant landscape type among all natural landscape resources, design of constructions in mountain landscapes should take multiple factors into consideration. Taking Science Popularization and Education Hall of Jiangxi Wuyi Mountain Nature Reserve for example, this paper explored the architectural design in mountain landscapes from the perspectives of spatial form, facade design, color materials and design experience, in order to achieve the integration of landscape constructions and natural environment.  相似文献   

12.
The objective function of minimum cost is established for double layer torsional reticulated shell, taking the rise-span ratio, grid size and shell thickness as design variables. Based on the exhaustion and 0.618 methods, the computing program LSD has been developed. For the double layer torsional reticulated shell with the span of 50 m to 80m, the optimal grid size and thickness have been obtained for systems of light roof materials with different spans. Empirical formulas are deduced from the results.  相似文献   

13.
[Objective] To discuss the safety of shampoo with compound Zaofan function to the skins of laboratory animals. [Methods]Kunming mice was used for skin acute toxicity test; domestic healthy rabbits were used for skin irritation test; and white guinea pigs were used for skin sensitivity test. Cell genetic toxicity of Shampoo with compound Zaofan function in the body was detected by lymphocyte micronucleus test on Kunming mice. [Results]After using the shampoo with compound Zaofan function,mice showed no symptom of acute toxicity. In skin irritation test,shampoo with compound Zaofan function had relatively weak stimulation to skin; and the degree was no irrigation. In skin sensitivity test,shampoo with compound Zaofan function had low incidence of sensitization and poor sensitization. In micronucleus test of lymphocyte,shampoo with compound Zaofan function had small effects on the teratogenicity / mutagenesis. [Conclusions]Shampoo with compound Zaofan function was safe and reliable for external use,and was worthy of clinical promotion.  相似文献   

14.
转玉米C4光合酶基因水稻株系中的光合C4微循环   总被引:9,自引:0,他引:9  
用转PEPC、PPDK、NADP-ME、PEPC PPDK等酶基因的水稻株系及原种野生型(WT)为材料, 研究了不同基因型水稻叶片中的C4光合微循环及其功能.用外源OAA或MA饲喂叶切片或离体叶绿体后,光合放氧速率在野生型水稻中增加了50%,在NADP-ME-和PPDK-转基因水稻中增加了50%~54%,在PEPC-和 PEPC PPDK-转基因水稻中增加了100%~150%.证明原种水稻Kitaake叶片中具有一个原初的和有限的C4光合微循环,除PPDK基因、NADP-ME基因外,外源PEPC基因或PEPC PPDK双基因导入原种水稻Kitaake后,可大幅度提高C4光合微循环的运行.水稻中C4光合微循环的增强有降低光呼吸速率(Pr)、增加净光合速率(Pn)的作用,在光能利用上,可增加PSⅡ光化学效率(Fv/Fm)、光化学猝灭(qp)、降低非光化学猝灭(qN)的作用;这些结果为转C4光合酶基因水稻中建立C4微循环系统来提高光合作用效率的可能性提供了依据.  相似文献   

15.
亚麻木酚素研究进展   总被引:8,自引:0,他引:8  
综述了亚麻木酚素的结构、代谢、功能及应用方面的研究进展。亚麻木酚素具有抗肿瘤生成作用、雌激素及抗雌激素效应、抗癌、抗动脉硬化、预防糖尿病、抑制芳香酶活性、抑制DNA和RNA合成、抗病毒、抗真菌等多种功效。在食品、临床医学和化妆品领域应用广泛。随着人类生活水平的提高和营养的变化,心血管疾病、癌症、糖尿病等与饮食习惯有关的疾病迅速上升,木酚素对于预防与防治这一类疾病意义重大,同时化妆品也成为一大消费领域,以木酚素为主要原料的化妆品可以预防或治疗肌肤衰老。木酚素在亚麻籽中含量非常丰富,中国又是亚麻的生产大国,开发亚麻木酚素会产生巨大的经济和社会效益,前景广阔。  相似文献   

16.
不同发育阶段绒山羊皮肤中FGF5基因mRNA表达的RT-PCR检测   总被引:4,自引:0,他引:4  
为深入研究成纤维细胞生长因子5对毛囊生长发育的生物学功能提供理论依据。在10月左右和1月左右,即皮肤毛囊处于生长旺期和退行期时采集了12只内蒙古阿尔巴斯白绒山羊皮样,利用TRIZOL试剂盒提取皮肤总RNA(一步法),利用RT-PCR方法检测FGF5基因在绒山羊绒毛周期性生长不同阶段皮肤中的表达分布情况,试验结果表明,FGF5基因mRNA在绒山羊毛囊生长旺期和退行期均有表达,却只得到了一种剪切形式的表达,经测序是长片段,而缺失外显子2的短片段形式没有检测到。  相似文献   

17.
夏玉米光合特性对氮素用量的反应   总被引:11,自引:0,他引:11  
随氮素用量增加,植株下位叶、穗位叶和上位叶的光合速率(Pn)、叶绿素含量(Chl)、可溶蛋白含量(Pro)、Hill反应活性、Ca2+-ATPase活性、Mg2+-ATPase活性和PEPCase活性均不断增大。植株不同叶位Pn和Pro随生长进程均不断下降;不同叶位Chl的变化动态表现为下位叶在各测定时期之间差异较小、穗位叶和上位叶为单峰曲线。Hill反应活力、Ca2+-ATPase活性和Mg2+-ATPase活性的变化规律不同,随生长进程表现不断下降、单峰曲线和双峰曲线等不同形式。各叶位PEPCase活性均表现单峰曲线型变化。随氮素用量增加,叶源量、生物产量和籽粒产量不断增加。适量施氮具有全面改善玉米光合效率和内在生理、生化过程的作用。Ca2+-ATPase活性是影响光反应活力的重要因素;在叶片生长前中期,Pn受到PEPCase的影响较小,主要受到光反应活力和暗反应效率的调控。可采用叶源量作为玉米单株生产力的参考诊断指标。  相似文献   

18.
Optimal Control of Semi-Active Suspensions with ER Shock Absorber   总被引:1,自引:0,他引:1  
An ER shock absorber with mixed mode is designed and its mathematical model is built. The optimal control method with LQ is applied to semi-active suspension systems in vehicle. A optimal output tuner is designed on basis of 1/4 dynamic model and the characteristics of the ER shock absorber. Its aim function and the weighting parameter matrix are determined. The feedback gain vector is found from solving the Algebraic Equation. The result shows that the optimal controller could not only diminish the body acceleration effectively but also improve the ride and handling characteristics. The construction of the ER shock absorber is reasonable and its performance meets the optimal control requirements of semi-active suspension system under the 3 kV/mm. In additional, the optimal control has low cost and energy consumption as well as rapid response . Such a system can meet with the requirements of semi-active suspension control completely.  相似文献   

19.
北京市粮食直接补贴政策的效率分析   总被引:1,自引:1,他引:0  
作为重要的农业支持政策,粮食直接补贴一直是中国各界关注的焦点问题;为了研究北京市粮食直接补贴政策实施的效率,依据相关政策和数据,通过采用Cobb-Douglas生产函数的回归分析,DEA方法以及Malmquist指数对北京市粮食直补及其效率进行了研究。结果表明,粮食直补变量在Cobb-Douglas生产函数的回归系数为正,并通过了显著性检验,粮食直接补贴在一定程度上促进了北京市粮食产量的增长;DEA结果显示,2009—2011年3年间北京市粮食直接补贴的综合效率平均值分别为0.909,0.837和0.901,北京市各区县的粮食补贴相对不同,表明北京市各区县的粮食直补效率各有不同的特点。  相似文献   

20.
农杆菌介导的牡丹江8号高效转基因体系的建立   总被引:27,自引:1,他引:26  
粳稻品种牡丹江8号具有繁殖周期短、对多个白叶枯病和稻瘟病生理小种感病或高度感病的优点,因此,是水稻抗白叶枯病和抗稻瘟病基因克隆研究中候选基因功能验证的一个理想受体.本试验通过对农杆菌侵染参数的优化,建立了农杆菌介导的牡丹江8号高效转基因操作体系.在3次重复试验中,该转基因操作体系抗性愈伤转化率分别为67.5%、 7  相似文献   

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