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1.
近年来,绿色建筑成为国内乃至国际建筑界、房地产界的一个热点话题,绿色建筑的发展也越来越受到关注,许多国家都开展了绿色建筑的研究和实践,取得了很多的研究成果.尤其在去年经历了一场与"非典"的斗争之后,人类更加深刻地认识到绿色建筑在生活中的重要性,由此也引发了一场关于绿色建筑的革命,将绿色建筑向更深入、更科学的方向推进.  相似文献   

2.
《技术与市场》2007,(2):22-22
超氧化物歧化酶是一种金属酶类,根据所含金属辅基不同,分为Cu、Zn-SOD,Fe-SOD,Mn-SOD和Ni-SOD四类.其中Cu、Zn-SOD主要存在于真核细胞的细胞浆中,如猪血、鸭血、猪肝等动物血液和内脏器官等组织中;Mn-SOD存在于真核细胞的线粒体、细菌中;Fe-SOD只存在于原核细胞中,如海藻中的螺旋藻、铁钉叶等;Ni-SOD是最近发现只存在于某些极少数原核细菌中.  相似文献   

3.
溶氧超标"毒水症" 危害及症状:水体中因施放过多未经发酵的肥料,生肥在塘底分解出很细小的甲烷和硫化氢的小气泡,鱼苗误当食物吞入.其主要症状是:鱼鳃上会粘附许多小气泡,使鱼体上浮或游动失去平衡.鱼的肠道中有白色气泡,或鱼的体表、鳍条、鳃丝上附有较多的气泡,鱼体漂浮水面,沉不下去,严重的可致鱼类成批死亡.  相似文献   

4.
With the interpreted IKONOS4 satellite images collected in 2005,a 1:10 000 forest map,the data collected in ClassⅡforest survey in 2007,and surface runoff data obtained in the permanent runoff monitoring station,six site factors of slope gradient, slope position,soil thickness,soil thickness of A layer,soil type and soil water content were selected to establish a matter element model suitable to 297 forest sub-compartments.Further,the AHP was applied to modify the spatial structure and form the spatial para allocation of the protection forest system. The results showed that:1) the area allocation of different vegetation types was irrational,the area of a mixed coniferous and broad-leafed forest was 124.39 ha,accounting for 14.97%of the forested land,the mixed forest was consisted of two coniferous species accounted for 27.37%of the total forest land,and the pure forest was consisted of one coniferous species accounted for 42.48%.2) After optimization,the area allocation of different vegetation types in the protection forest system ranked as:the mixed coniferous and broad-leafed forest(31.12%)>shrub land(15.5%)>the economic tree crops(12.28%)>the mixed forest consisting of two coniferous species(11.46%)>the pure broad-leafed forest(11.41%)>the pure coniferous forest(9.51%)>grass land(8.70%). Besides,the annual surface runoff could reduce 43 171 mm or 62.15%,annual soil erosion could decrease 465.97 t or 79.66%.3) The following suggestions for spatial para allocation of the small watershed protection forest system were proposed: (1) Reducing pure cypress or pine forest,and increasing alder-cypress,oak-cypress or pine-cypress mixed forest.As for the current cypress and pine pure forests,alder or oak could be introduced to develop a mixed forest.(2) The canopy closure of pure cypress forest and alder-cypress forests should be maintained within 0.60-0.75,and the canopy closure of oak-cypress,pine-cypress or oak-pine forests should be controlled within 0.60-0.80. (3) For improvement of current pure  相似文献   

5.
多功能水箱     
《技术与市场》2007,(5):16-16
多功能水箱,绿色、环保、安全、方便,提高了水质,促进使用者的身体健康.该水箱代替了水缸、水桶、水壶、暖水瓶,纯净水机,悬挂在壁角上,不占用地面面积.  相似文献   

6.
中小企业财务管理面临的问题及对策   总被引:3,自引:0,他引:3  
中小企业是中国国民经济的重要组成部分,在国家经济生活中占有极其重要的地位.中小企业要快速、稳定、健康地发展,必须要清醒地认识到财务管理在企业经营中的重要地位和作用,本文针对当前我国中小企业财务管理方面存在的问题,从几个方面进行了分析,并提出了相应的措施.  相似文献   

7.
The carbon cycle of forest ecosystems plays a key role in regulating CO2 concentrations in the atmosphere. Research on carbon storage estimation of forest ecosystems has become a major research topic. However, carbon budgets of subtropical forest ecosystems have received little attention. Reports of soil carbon storage and topographic heterogeneity of carbon storage are limited. This study focused on the Jinggang Mountain National Nature Reserve as an example of a mid-subtropical forest and evaluated soil and vegetation carbon storage by field sampling combined with GIS, RS and GPS technology. We classified the forest into nine forest types using ALOS high-resolution remote sensing images. The evergreen broad-leaved forest has the largest area, occupying 26.5% of the total area, followed by coniferous and broad-leaved mixed forests and warm temperate coniferous forest, occupying 24.2 and 22.9%, respectively. The vegetation and soil carbon storage of the whole forest ecosystem were 1,692,344 and 5,514,707 t, with a carbon density of 7.4 and 24.2 kg/m^2, respectively, which suggests that the ecosystem has great carbon storage capacity. The topographic heterogeneity of the carbon storage was also analysed. The largest vegetation storage and soil storage is at 700–800 and 1000–1100 m, respectively. The vegetation carbon storage is highest in the southeast, south and southwest.  相似文献   

8.
毛叶山桐子(Idesia polycarpa Maxim.var.vestita Diels)大风子科山桐子属,落叶乔木,树干通直,侧枝长,树型美观.叶互生,宽卵形至卵状心形,端尖;边缘有疏锯齿,掌状基出脉5~7,叶片下面密生短柔毛或密毡毛,叶柄与叶等长,顶端有2突起的腺体;花多为单性,黄绿色,有香味,下垂圆锥花序;浆果球形,其果色为红色或黑色.  相似文献   

9.
1.绿博会筹备和举办期间,承担全国绿委在郑州举行的各类会议、活动费用。2.各参展团室外建园,建园面积不少于1500平方米,给予人民币10万元补贴,并提供东风日产帕拉丁越野车(ZN6453WAG3型标  相似文献   

10.
前两天,在一家网站的涂鸦馆里看到这样一幅图画:一个小牛形状的面包被切成几片站立在我的面前。作者为它的创意起了一个名字叫"分享",意思是面包要一起食用。图画下面一位网友的跟帖引起了我的注意。  相似文献   

11.
简要概述石蒜属植物的种质资源、分布状况、药用价值和化学成分,分析比较了江西不同地区的石蒜和忽地笑的石蒜碱含量。  相似文献   

12.
澳大利亚辐射松遗传育种及其借鉴   总被引:1,自引:0,他引:1  
澳大利亚辐射松遗传改良在过去的几十年中取得了较大的成绩, 其育种计划与育种策略在一定程度上反应了当前世界林木育种水平。较详细地介绍与分析了澳大利亚辐射松遗传改良的历程与成就, 供我国林木育种工作者参考。  相似文献   

13.
以2年生红花石蒜小球为研究对象,设6种施肥处理,研究物质积累和分配规律.结果表明:总鲜质量、球茎鲜质量、根鲜质量以及体积在施肥处理间的差异均达到极显著水平,叶鲜质量、萌芽数处理间差异达到显著水平,折干率在处理间不存在显著性差异,所有处理的叶片鲜质量与总鲜质量的相关系数最高,均值高于0.991;总干质量、球茎干质量和根干质量在施肥间的差异均达到极显著水平,叶片干质量在处理间达到显著差异,球茎干质量与总干质量的相关系数最高,均值在0.990以上;处理1~3有利于干鲜物质积累,为较好的施肥方案,建议在实践中推广应用.  相似文献   

14.
在红花石蒜不同生长发育期进行八分法切割繁殖,研究无性繁殖系数和子球生物学性状差异性.结果表明:(1)不同生长发育期无性繁殖系数在0.80~6.80之间浮动,休眠期的6、7月和旺盛生长初期的9月繁殖系数较高;(2)不同生长发育期无性繁殖的子球鲜质量、最大直径、子球高度、根系长度、根基粗度及根系数量等生物学性状均呈现1%水平极显著差异.综合分析认为休眠期的6、7月,旺盛生长初期的9月及生长后期的4月是适宜无性繁殖的季节.  相似文献   

15.
对盆栽的伴生有金雀花(Cytisus scoparius)、黑麦草(Lolium multiflorum)的辐射松(Pinus radiata)幼苗施用3种浓度(O,50,100 μg·g-1)的三过磷酸钙,14个月后测定缺磷Allophanic土壤中各磷形态变化,确定根际土壤中施加的磷肥的去向.结果表明,施加磷肥增加了根际土壤中NaOH-Pi、NaOH-P0和H2SO4-Pi的浓度,但是减少了土壤残留磷的含量,而树脂磷浓度维持不变,在这种土壤中树脂磷浓度仍然较低(1 to 3μg·g-1).施加到土壤里的磷肥,有机磷的回收率最高(40%-49%),这是因为这种土壤具有较高的磷固定能力(92%),其次是不稳定有机磷(7%-19%).在磷肥缺乏或不施加磷肥的情况下,辐射松根际土壤中有机磷浓度低于周边土壤以及金雀花、黑麦草根际土壤.这可能与磷肥缺乏条件下,根系和菌根产生较高的草酸盐而释放部分磷到根际土壤中有关.但此观点需要进一步的研究检验.  相似文献   

16.

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.  相似文献   

17.

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.  相似文献   

18.

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.  相似文献   

19.

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.  相似文献   

20.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。  相似文献   

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