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1.
1摘要的要素 目的——研究、研制、调查等的前提、目的和任务,所涉及的主题范围。方法——所用的原理、理论、条件、对象、材料、工艺、结构、手段、装备、程序等。结果——实验的、研究的结果,数据,被确定的关系,观察结果,得到的效果,性能等。结论——结果的分析、研究、比较、评价、应用,提出的问题,今后的课题,假设,启发,建议,预测等。  相似文献   

2.
 中国人民具有伟大梦想精神,中华民族充满变革和开放精神。自西学东渐以来,有识之士为科学救国而奔走呼号,空有才华却报国无门。只有在中国共产党的领导下,科技工作者才真正实现了科技报国、科技兴国的人生抱负。新中国成立以来,以钱学森、邓稼先、郭永怀、袁隆平、黄旭华、屠呦呦、赵忠贤等为代表的老一辈科技工作者,以强烈的家国情怀,艰苦奋斗,不懈创新,为国家富强、民族振兴、人民幸福作出了彪炳史册的重大贡献。在改革开放和创新型国家建设的伟大征程中,李保国、黄大年、南仁东、钟扬、王逸平等当代科技工作者,把论文写在祖国大地上,以丰硕的创新争先成果,诠释了心有大我、至诚报国的浓烈情怀,不愧为国家栋梁、民族脊梁、人民赤子。一代代科技工作者,用忠诚、信仰、学识、青春甚至生命,铸就而成爱国、创新、求实、奉献、协同、育人的中国科学家精神。不管时代如何变化,这种精神始终能够薪火相传并愈加焕发出勃勃生机,召唤激励着更多科技工作者披荆斩棘、砥砺前行。 伟大梦想不是等得来、喊得来的,而是拼出来、干出来的。面临科技革命和产业变革的历史交汇期,面临世界百年未有之大变局,面临复杂严峻的国际形势,我们犹如逆水行舟、滚石上山,进则海阔天空,退则前功尽弃。形势逼人、挑战逼人、使命逼人。科技工作者作为时代中坚、社会之光,必须不畏任重,不惧时艰,把个人理想自觉融入科技强国伟业,洞察变革于端倪,把握先机于初始,引领方向于“无人区”,补短板、增长板,摆脱核心技术受制于人的局面,打造未来竞争新优势,在奋斗中成就创新梦想、实现人生价值。 周虽旧邦,其命维新。建成社会主义现代化强国,实现中华民族伟大复兴,是一场接力跑。面对新征程新使命,走过一甲子的中国科协,将进一步融入大局、聚焦靶心,团结引领广大科技工作者坚定信仰、秉持信念、满怀信心,接力精神火炬,奋进新的长征,一棒接着一棒跑下去,赢得更大的荣光,创造更大的奇迹!  相似文献   

3.
张玉善  李永刚 《科技资讯》2006,(29):184-184
樟子松是常绿乔木,它适应性强,耐干燥瘠薄,在风积沙土、砾质粗沙土、沙壤土、黑钙土、栗钙土、淋溶黑土、白浆土上都能生长。它耐寒性强,能耐-50℃的低温,耐旱,对土壤水分要求不严,根系发达,可充分利用土壤水分,固沙、固士效果良好,是营造速生用材林、各种防护林的重要树种,现得到广泛得应用,据此,本文针对樟子松的营造技术进行了分析,以供参参考。  相似文献   

4.
《安徽科技》2006,(1):28-29
按照科学技术部《关于开展2003~2004年度全国市、县、区科技进步考核工作的通知》的要求,在安徽省科学技术厅对参加考核市、县、区进行规定指标考核的基础上,科学技术部组织专家组本着公开、公正、公平的原则,对“三个一票否决”指标进行复核,日前,科学技术部批准安徽省全国科技进步考核市(县、区)有:合肥市,芜湖市,马鞍山市,铜陵市,淮南市,合肥市蜀山区,合肥市包河区,淮南市田家庵区宁国市,肥西县,肥东县,黄山市黄山区,芜湖县,天长市,桐城市,淮南市毛集实验区,怀远县,和县,黟县,繁昌县,凤台县,宣城市宣州区,铜陵县,祁门县,舒城县,五河县,当涂县,界首市,南陵县,含山县,巢湖市居巢区,广德县,淮南市谢家集区,黄山市屯溪区,歙县,池州市贵池区,绩溪县,郎溪县,无为县,临泉县,淮北市杜集区,灵璧县,淮南市八公山区,滁州市南谯区,淮南市潘集区,庐江县,怀宁县,砀山县,东至县,萧县,明光市。  相似文献   

5.
夹竹桃NeriumimdicumMill,原产伊朗,引入我国栽培时间较长,它喜温暖湿润气候,不耐严寒,其叶象竹叶,花似桃花,花期六至十月,花色有红、黄、白三种,园林中多见红花,稍见白花、黄花。夹竹桃愈伤组织发达,抗性较强,对生境条件要求不严,扦插繁殖、引植、片植或独植,均十分容易成活,并有立竿见影的绿化效果。它花期较长,四季常青,抗尘抗毒能力极强,是抗二氧化硫最强的十二树种之一,每平方叶面积吸尘量可达5克之多。由于夹竹桃具有优良的生物学特性,在我国栽培面积较广.华东、华中、中南、西南诸省、区的道路庭院、工厂矿山…  相似文献   

6.
薏米又叫薏仁、苡米、药玉米等。有健脾、渗湿、排脓等功效,治脾虚腹泻、肌肉酸痛、水肿、肺脓疡、阑尾炎等症,是中药材市场常年畅销的大宗籽仁类药材。除药用外,它还是营养丰富的食品,食品工业做八宝粥、糕点,保健品、天然美容品用量很大,国内用量需求每年增长20%,且出口量日益增加,价格坚挺上涨。意米是目前发展种植的最佳项目之一,生长期同玉米一样,收入则比同期种植的玉米、大豆、水稻等农作物高出数倍c意米为一年生草本植物,株高l一Zcm,茎直立、粗壮,上部分多分枝,具有明显的节,节间中空。叶互生,纵向排列,叶鞘与叶…  相似文献   

7.
梅文鼎是我国清初杰出的民间数学家和天文学家,他努力吸取中国传统数学的精华和西学东传的先进科学知识,把西方数学、天文学与中国传统数学、天文学结合起来,融会贯通,并有自己的创造.他积60年之精力,著书88种,内容涉及算术、代数、几何、三角、测量以及对我国传统天文学研究、评述和西方天文学介绍等.家学相传,在他的带动、教诲和影响下,梅氏家族数学人才辈出,其弟文鼐、文,子以燕,孙珏成,成,曾孙、、、钫、、,玄孙冲也都学有专长,有许多历算著作问世.梅氏家族祖孙五代对科学矢志不渝的追求,为中国天文历算的发展做出了伟大贡献  相似文献   

8.
《浙江科技学院学报》2005,17(2):105-105
微机控制自由行程升降机构是采用计算机控制的机电自由行程升降机构,而国内目前的升降机构一般采用液压驱动,比较而言,本机构结构轻巧、紧凑,运行自如,,生产成本低,升降行程用计算机自由控制,可实现单动、联动、自我检测、故障诊断、操作错误报警、安全停机等功能。本机构的升降速度可以调节,机构采用剪式结构,适用于高空作业,也可用于装、卸、提升等综合性作业的场合,升降速度1~30m/min,  相似文献   

9.
“一杯鲜豆浆,天天保健康”,民间的说法一点不错。鲜豆浆营养丰富,味美可口,富含人体所需优质植物蛋白,八种必需的氨基酸,多种维生素及钙、铁、磷、锌、硒等微量元素,不含胆固醇,并且含有大豆皂甙等至少五六种可有效降低人体胆固醇的物质,鲜豆浆的大豆营养易于消化吸收,经常饮用,对高血压、冠心病,动脉粥样硬化及糖尿病、骨质疏松等大有益处,还具平补肝肾、防老抗癌、降脂降糖、增强免疫的功效。  相似文献   

10.
沙棘林经营管理应注意的问题   总被引:1,自引:0,他引:1  
沙棘适应性极强,抗严寒、风沙,耐大气干旱和高温,喜光照,耐水湿、盐碱及干旱瘠薄。其根系发达,生长快,是防风固沙、保土、保水和改良土壤的造林先锋树种,具有极强的拦蓄径流、拦洪落淤、稳定坡面、固土防冲的作用。还是优质薪柴,火力旺、热值高,相当于同等数量的标准煤。其叶是干旱春季牲畜度春荒的好饲料,对保持牲畜膘情,提高越冬能力,可起到积极作用。沙棘集生态效益、经济效益和社会效益于一体,是治理水土流失,改变生态环境,促进贫困地区经济发展,脱贫致富的有效武器。只要我们进行科学的经营管理,其产生的效益是巨大的。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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