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1.
 在国家自然科学基金的连续资助下 ,中科院北京真空物理开放实验室、中科院化学所、北京大学电子学系、北京大学化学学院科研人员组成的联合科研小组 ,采用与国外不同的原理、设计和方法 ,设计、制备了一系列新型有机复合和有机分子信息存储薄膜 ,成功地实现了超高密度的信息存储 ,在有机超高密度信息存储材料领域取得了一系列突破性进展 ,在《应用物理快报》(Appl.Phys.Lett.)、《物理评论快报》(Phys.Rev.Lett.)等国际上有重要影响的杂志上发表了多篇论文。  相似文献   

2.
在国家自然科学基金的连续资助下 ,中科院北京真空物理开放实验室、中科院化学所、北京大学电子学系、北京大学化学学院科研人员组成的联合科研小组 ,采用与国外不同的原理、设计和方法 ,设计、制备了一系列新型有机复合和有机分子信息存储薄膜 ,成功地实现了超高密度的信息存储 ,在有机超高密度信息存储材料领域取得了一系列突破性进展 ,在《应用物理快报》(Appl.Phys.Lett.)、《物理评论快报》(Phys.Rev.Lett.)等国际上有重要影响的杂志上发表了多篇论文。1996年他们采用自行设计、合成和制备的全有…  相似文献   

3.
超高密度信息存储材料及技术研究进展   总被引:5,自引:0,他引:5  
信息技术的飞速发展,要求不断开发出具有更高信息存储密度及更快响应速度的材料和器件,因而在纳米尺寸上实现信息存储功能的新型超高密度信息存储材料已成为当前信息领域一个发展速度快、学科交叉多、竞争十分激烈的研究热点.简要介绍了近年来该领域主要的研究方法,并着重对利用扫描隧道显微镜/原子力显微镜(STM/AFM)写入信息的存储材料的最新研究进展进行了综述.  相似文献   

4.
有机—无机纳米复合材料的研究进展   总被引:19,自引:0,他引:19  
综述了有机-无机纳米复合材料的最新发展,包括该类材料的制备方法、性能研究和应用前景.三种主要的纳米复合技术为溶胶-凝胶法、嵌入法和纳米微粒填充法.纳米复合材料的光学和磁学等性能可用Maxwel形态理论、层状结构理论和分形结构理论等来研究.这类材料已在力学、热学、电学、磁学、光学、宇航和生物仿生等领域表现出广泛的应用前景.  相似文献   

5.
随着信息技术的飞速发展,人类要处理的信息量与日俱增,要求不断开发具有更高信息存储密度及更快响应速度的材料和器件。如何提高读写速度、实现纳米尺度信息存储是目前迫切要解决的问题。超高密度信息存储是指信息存储密度大于1012比特/平方厘米(1太比特/平方厘米),实现从电子器件从“吉时代”到“太时代”的跨越。与目前市售电子器件的存储密度相比,其信息存储能力堪称惊人。超高密度信息存储材料和器件作为纳米电子学的重要内容之一,将为未来信息技术的发展奠定理论和技术基础。  相似文献   

6.
快速超高密度外存储基础技术通过鉴定我校计算机外存储系统国家重点专业实验室研制的一种新技术能使目前磁盘存储器的信息容量扩大一个数量级,接收速率提高3倍.“快速、超高密度外存储基础技术”已于2月中旬通过了鉴定.专家鉴定认为,该课题研究水平达到了当前国际先...  相似文献   

7.
本文从光盘的存储密度、数据传输率和超高密度存储三个方面讨论了提高光盘信息存储的关键技术。  相似文献   

8.
主要介绍了二维纳米薄膜、三维纳米晶体材料和纳米复合材料的制备方法。探讨了各种方法的特点与适用性,并展望了纳米材料在催化、光学、电学、磁学,传感器、陶瓷及生物医学等领域的应用前景。  相似文献   

9.
一维纳米结构材料的制备与组装   总被引:7,自引:0,他引:7  
一维纳米结构材料在纳米电子学、纳米光电子学、超高密度存储和扫描探针显微镜诸多领域具有潜在的应用前景,已成为21世纪化学、物理学、材料学及生命科学等科技领域的研究热点。结合近期研究工作,主要介绍了一维纳米结构材料的制备方法和组装策略,并简要概述了一维纳米结构材料的应用前景及其国内外最新研究进展。  相似文献   

10.
尿素-NaBr低温熔盐体系中Er-Co合金的电沉积   总被引:15,自引:1,他引:14  
稀土元素内层4f电子的数目从0~14逐个填充,造成它们之间在光学、磁学、电学性能上出现明显差异.衍生出种类繁多的高新材料[1].稀土铁族金属合金具有优良的磁性、磁光性并可应用于磁性元件及磁光记录材料,目前多采用蒸镀和激光溅射法制备.但设备成本高、生...  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
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   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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