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1.
阿魏属和独活属都是伞形科中具有重要药用价值的植物。但是由于伞形科的分类系统是建立在典型的伞形花序和带有特殊分泌管的果实的基础之上的,使得分类学者在亚科、族、属和种的设立和分类方面存在分歧,实验主要针对阿魏属和独活属的花粉形状进行研究,对阿魏属和独活属植物的分类提供一些基础数据。利用光学显微镜和扫描电子显微镜拍摄了伞形科阿魏属5种和独活属3种植物的花粉照片,进行了花粉形态的比较研究。结果表明,阿魏属花粉形状为长球形,而独活属花粉为超长球形;2属花粉外壁均具有网状纹饰,3孔沟。阿魏属和独活属植物的极轴平均长度分别为29.67μm和34.07μm,秩和检验表明二者差异显著;赤道轴平均长度17.07μm和15.65μm,差异不显著;极轴长/赤道宽的平均值分别为1.76和2.19,差异显著。  相似文献   

2.
中国城市市花市树研究   总被引:1,自引:0,他引:1  
市花市树往往是一个城市的象征,反映城市市民的文化传统、审美观和价值观。调查了当前全国各省地级市及直辖市市花市树评选情况,分析了所选用市花市树的种类状况和特征及不足,发现292个城市中有167个城市评选了市树,209个城市确定了市花;所选的植物种的重复率较高,平均3个城市选用的市花或市树雷同,市花市树分布48个科,76个属,106种;市民对市花市树的认知不够,对市花市树的宣传不足,多数城市的市花市树缺少植物学名,主要以俗称为主等情况。剖析了目前这种状况的背景与原因.并为如何充分开发市花市树提出了建议。  相似文献   

3.
云南省楚雄州自然分布(少数几种为栽培)的双子叶植物有2939种(含种以下单位),隶属170科914属。本文对其区系成分进行了统计分析,结果表明双子叶植物科的分布类型主要是以热带——亚热带分布型(41科,占24.18%)和热带——温带分布型(31科,占18.24%)为主。属的分布类型主要以泛热带分布型(243属,占26.59%)、东亚分布型(112属,占12.25%)和北温带分布型(94属,占10.28%)为主。楚雄州双子叶植物区系特征有以下显著特点:①植物种类丰富;②区系成分复杂、起源广泛;③热带、亚热带成分突出。  相似文献   

4.
Diao Long 《保鲜与加工》2013,(Z1):241-243
Linkage control of fire-fighting electrical equipment effectively and reasonable design, installation and debugging of power supply and distribution are increasingly important to ensure the safety of underground space. As the linkage control systems associated with the fire control electrical equipment are very complicated, and the distribution of installation and debugging are very professional, there are many hidden troubles of safety in the whole life cycle process. On the basis of analysis of characteristics of underground space of fire, underground fire-fighting electrical equipment and the requirement of power supply system are expounded, hidden dangers on linkage control of electrical devices and design installation and debugging of power supply and distribution underground space are analyzed, and some suggestions and countermeasures are provided for relevant departments as decision-making reference.  相似文献   

5.
For a reinforce concrete frame structures which is not satisfied the standard for seismic appraiser of building, viscidity dampers are used to retrofit the structure. Four reinforce schemes are selected in which six same viscidity dampers are located at different position of the structure. Compared seismic performance of the retrofited structure with unretrofited one, an optimum scheme where viscidity dampers should better set is obtained. Then the number and technical parameter of viscidity dampers are adjusted, and seismic performance of the structure are calculated. The results are compared and a more economic scheme is obtained because the cost is lowest and the displacement of the structure under earthquakes is satisfied the standard for seismic appraiser of building. Several rules and advices are gotten about how to use the viscidity dampers to retrofit reinforce concrete frame structures. The conclusion about viscidity dampers are useful for similar actual engineering.  相似文献   

6.
不同月份元宝枫叶内黄酮、绿原酸含量的变化   总被引:5,自引:0,他引:5  
以5年生元宝枫苗为试材,用方差分析和多重比较的方法研究了元宝枫叶内黄酮、绿原酸含量及有关成分随月份的变化规律。结果表明:元宝枫叶内黄酮含量8月份最高,含量高达5.86%,绿原酸含量6月份最高,含量高达3.62%,SOD酶活性8月份最高,叶绿素含量6月份最高,可溶性糖含量9月份最高,月份不同其含量也不同,不同月份下,黄酮、绿原酸、叶绿素、可溶性糖含量均以a=0.01水平上差异极显著,而SOD酶活性以a=0.05水平上差异显著。  相似文献   

7.
以4个抗性不同的辣椒品种为材料,8叶期时采用孢悬液灌根接种的方法,分析测定了不同抗性品种接种辣椒疫霉菌后脯氨酸、丙二醛及可溶性糖含量的变化及其与抗病性的关系。结果表明:脯氨酸、丙二醛及可溶性糖的含量在接种后增长速度与积累量是决定辣椒抗病力强弱的关键性生理活性物质,脯氨酸与可溶性糖含量高、丙二醛含量低的品种抗疫病力强,相反,脯氨酸与可溶性糖含量低、丙二醛含量高的品种感疫病力强。  相似文献   

8.
由于卧龙山庄原规划已时过境迁,已经不能满足需要,因而急需进行重新规划和对规划后的方案进行系统评价。该文通过实地调查、GPS定位相结合的方法查清了现有旅游资源并在此基础上进行了规划,然后运用景观生态学方法对规划后的方案进行了评价。该文规划种植了酸枣、冬枣、梨枣、月光枣、野菜、柿子、欧李,改变了蔬菜园的种植种类;增加了杜梨、栾树和红叶臭椿的种植面积;规划了生态集雨工程示范点、火箭消雷展览室、卧龙禅寺、金鱼池、观鱼长廊、商店、观景亭、道路、停车场和厕所等。用斑块水平和景观水平上的景观指数作为规划方案评价的数量指标,对规划后的效果进行评定,认为规划后虽然景观破碎化指数提高了,但景观类型集中度加强;景观多样性指数、优势度指数、丰富度均提高了,美学质量得到改善,旅游设施更为完善,游览期更长;同时认为这种评价方法在规划方案筛选中具有一定的可行性和参考性。  相似文献   

9.
水稻冠层垂直反射率模拟   总被引:5,自引:0,他引:5  
利用1999年和2000年实测的晚稻冠层结构参数(叶面积指数、叶倾角、叶长、叶宽等)和叶片生物化学组分含量(叶绿素、蛋白质、纤维素、水等)实测数据,结合椭圆分布函数模型、PROSPECT模型和FCR模型,模拟水稻冠层垂直反射率,模拟值与实测值的相关系数大于0.98,均方根差RMSE小于0.05,从而建立了冠层结构参数、叶片生物化学组成等农  相似文献   

10.
台湾软枝杨桃的引种及其适应性研究   总被引:6,自引:0,他引:6  
研究了若干杨桃品种的生物学特性、适应性及其经济效益,结果表明:软枝杨桃、香蜜杨桃等品种适宜在漳州地区栽培,尤其以台湾软枝杨桃最为适宜。台湾软枝杨桃平均果重210g,可溶性固形物8.5%、总酸0.04%,平均种子数10个,周年开花结果,品质优异,市场批发价6~8元/kg,效益好。并提出了该品种配套栽培技术要点。  相似文献   

11.
调查了从台湾引进的珍珠番石榴、新世纪番石榴和水晶番石榴3个品种,通过生物学特性、适应性和经济效益的比较,认为这些品种都适宜在漳州栽培,尤其以珍珠番石榴为最适宜。珍珠番石榴平均果重422.1 g,硬度9.0 kg/cm2、可溶性固形物12.6%、总酸0.21%,Vc 88.92 mg/100 g,总糖含量6.7%,还原糖含量2.98%,周年开花结果,品质优异,市场批发价5~6元/kg,效益好。并提出了该品种配套栽培技术要点。  相似文献   

12.
华南地区棕榈科植物主要病虫害及其防治   总被引:1,自引:0,他引:1  
描述了华南地区棕榈科植物病虫害的调查情况,其中危害比较严重的主要有华棕立枯病、华棕芽腐病、华棕炭疽病、加拿利海枣叶斑病、加拿利海枣假黑粉病、海枣萎缩病等6种病害和椰蛀犀金龟、椰心叶甲、椰花二点象、红棕象甲、桉袋蛾、黑翅土白蚁、蛴螬等7种虫害。针对病害的症状、病原及虫害的形态进行了详细的描述,研究了这几种病虫害的发生规律与危害情况,并提出一些相应的有效防治方法  相似文献   

13.
The term Cleaner Production(CP)and Estimation of Cleaner Production Potential are introduced, meanwhile their importance are pointed out. Three kinds of cleaner technologies are put forward-Best Available Technology(BAT), Best Economic Attractive Technology(BEAT), and usually used new technology, combined with some CP casesat home and abroad. several cleaner technologies are compared, and the results show that the implementation of CP can greatly reduce consumption of resource and energy and pollution emission, There are obvious environmental, economic and social benefits. The great potential of CP in industrial pollution control are estimated and demonstrated ultimately.  相似文献   

14.
A great deal of electronic documents will be produced in enterprises, many of which in the form of disk files are stored in the computers of each department. Some are shared through the sharing mechanism, but they are difficult to manage and maintain. Security problems and information-isolated island may occur for some of these documents. A new technology of electronic document administration are introduced, in which authorized administration mechanism are taken and the documents are classified, encrypted, compressed and then transported via intranet and stored in database. Its application in enterprises has proved that documents can be shared and queried dynamically, conveniently and reliably by using the technology.  相似文献   

15.
研究国内外学者关于利他行为的思想、观点,总结利他行为的发展和争鸣,为后人研究利他行为提供理论依据和借鉴。本文在相关文献资料的基础上,采用实证描述和规范研究的分析方法,探讨了亲缘利他、互惠利他和纯粹利他等利他行为,并从自然选择、群体选择、基因选择、亲缘选择、互惠利他、自私基因、囚徒困境、纯粹利他等理论视角对利他行为进行解读和讨论。  相似文献   

16.
The finite element model involving geometric large deformation,materials and contact nonlinearity is established.Specimens of cold-formed steel quadruple-C built-up section members are simulated and the finite element models are proved to be valid.Then,numerical analysis on the behavior of specimens with different slenderness ratio and flange flakiness ratio are carried out,and then the axial bearing capacities of specimens are obtained.Based on effective width method and direct strength method (DSM) in related codes,two design methods of cold-formed steel quadruple-C built-up section members under axial compression are proposed:effective length method and correction factor method.It is shown that:the final failure characteristics of all specimens are local buckling and distortional buckling.In the case of not considering the reduction of effective length,the results calculated by each code are slightly lower than those of test and FEM when the slenderness ratio is less than 50,while the results are too conservative when the slenderness ratio is more than 50.  相似文献   

17.
The recurrent selection schemes recommended by CIRAD for 6 tropical tree crops are presented and compared. Breeding programmes are carried out under cooperation between CIRAD and its partners in regions where the crops are grown. The crops are cacao, coffee, rubber tree, oil palm, coconut and eucalyptus. After a short look at the background, the reasons behind the options chosen are given and the main characteristics of the schemes are described and illustrated. The state of progress and some major results are discussed. Over and above the differences linked to plant biology, the genetic diversity available and the type of varietal output, common characteristics are emphasized. The time taken for each generation means simplifying the intercrossing phases between successive breeding cycles, and thus, the parents tested are heterozygous: whenever possible, a clonal varietal output is an additional source of progress. The use of biotechnologies to study diversity is a valuable asset, and their application for early selection (QTL) is also promising. The preponderance of combining ability coexists with marked heterosis, which poses the problem of the latter's origin. As a result, all of the schemes described, but one, are reciprocal recurrent selection schemes. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

18.
In this paper, the solution of cylindrical bending problem for rectangular plates supported by elastic and tensile supports on particular deformation condition are derived from practical engineering problem. By examples, some considerable matters of analysing prismatic structures are suggested. The solutions are also studied when the tensions are to be determined. the results are simple and easy to be used.  相似文献   

19.
Four sigmoid growth functions and two exponential functions are described. Relevant values are calculated for estimated functions and presented in tables. Six examples are presented and interpreted. Estimated functions and contour plots for the rate of relative growth are shown in figures. Functions are estimated with SAS 6.12 and STATISTICA 5.0.  相似文献   

20.
根据食用植物油中的特征物质、甘三酯及脂肪酸组成的不同,研究了一些食用植物油的掺假检测,分析了这些检测方法的优缺点及影响因素,并对掺伪检测技术的发展方向进行了展望。  相似文献   

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