查询词典 structures

Dicotyledon leaves and some stem structures e.g.

但是茎的生长方向也会随光线改变。

With principal component analysis of the specific relationships between small mammal community and habitat structure, dicotyledon biomass and horizonal structure heterogeneity of the vegetations were major factor to influence the distributions and community structures of small mammals.

小哺乳动物群落与栖息地关系的PCA分析表明，植被的双子叶植物生物量和植被水平结构异质性是影响小哺乳动物分布和群落结构的主要因素。

Some of them have been studied by X-ray diffraction technique, and their crystal structures are reported precisely.

近年来，人们对糖类化合物的合成方法、结构表征和生物活性进行了深入而广泛的研究。

The structures of the composites are studied by X-ray diffraction.

采用XRD对复合材料的物相结构进行了分析。

By automatically selecting the optimal diffusion constant and iterative number, the filtering process is totally automatic and does not require any operator assistance and the diffusion is suppressed or stopped at boundaries and edges and small structures are retained.

正是在这样的背景下，本研究针对计算机集成相控HIFU治疗计划中的两项关键技术：序列医学断层图像的分割及其体视化技术，进行了理论研究和算法的设计。

During fabrication and use, diffusive processes can relocate matter, so that the structures evolve over time.

在制造和使用中，扩散过程能够重置物质，因此结构随时间演化。

Cathodoluminescence and δ〓O、δ〓C values of the sparites of geopetal structures within fossil brachiopods indicate that the sparcalcites were formed in equilibrium with various stages of postdepositional digenesis or catagenesis with each stage's δ〓O of interstitial water different.

3碳酸盐岩早期成岩胶结物或孔洞充填中的亮晶方解石是除腕足化石外获取碳酸盐岩原始氧、碳同位素组成的又一种常用样品。但本论文研究发现，龙门山地区碳酸盐岩的成岩后生改造具有多期多次现象，不同改造期次的流体之间存在明显的δ〓O差异，但无明显的δ〓C差别。

In this paper, the concept of network security and security structures of OSI and Internet is introduced, and various threats confronting the computer network are also discussed. Several kinds of network information security technologies, including firewall technology, virtual private network, intrusion detection system, data encryption technology, identity authentication and security protocol etc. are also examined. The security of internal network is the biggest problem in the construction of each network. The solution to this problem lies in setting up a firewall. The theory of a firewall and the approach to its actualization is studied. Intrusion detection system, an important part of the computer network security system, has gained extensive attention. IDS monitors the computer and network traffic for intrusion and suspicious activities. It not only detects the intrusion from the extranet hacker, but also the intranet users. The emergence of virtual private network paves the way for realizing secure connection of LAN quickly and at a relatively low cost. The concept, function, key techniques, including the tunnel technology, and the ways to realize VPN are expounded in this paper. Also introduced is the data encrypt network technology, which is called the soul of computer network security, such as digital digest, digital signature, digital certificate, digital encrypt arithmetic and so on. At the same time, the principle and the process of implementing network security by digital certificate and digital signature, the basic principle and characters of security protocols, and finally, three of the security protocols, concerning the security problems in network, IPsec, SLL and SET are analyzed in detail Computer network system should be a system of dynamic defence, both dynamic and static, passive as well as active, and even offensive, combined with management and technology.

本文系统地介绍了网络安全的概念、OSI及Internet的安全体系结构，并讨论了计算机网络面临的各种安全威胁；内部网络的安全问题是每个建网单位面临的最大问题，可以认为防火墙技术是解决网络安全的一个主要手段，本文研究了防火墙的原理及其实现手段；作为一种主动的防御措施，入侵检测系统作为网络系统安全的重要组成部分，得到了广泛的重视，TDS对计算机和网络资源上的恶意使用行为进行识别和响应，不仅检测来自外部的入侵行为，也监督内部用户的未授权活动；虚拟专用网技术的出现，为实现网络间的连接提供了快速安全但又相对便宜的手段，本文较深入的探讨了实现VPN的隧道技术，并对VPN的概念、功能、实现途径、基本构成、关键技术及发展前景等问题进行了全面论述；数据加密技术是网络安全核心技术之一，本文从数据加密算法、数字摘要、数字签名及数字证书等几方面简要介绍了数据加密技术，并分析用数字证书和数字签名实现网络安全的原理和过程；对安全协议的基本原理、主要特点进行了较为深入的研究，并就网络的安全性问题剖析了三种安全协议：IPsec协议、SLL协议和SET协议。

Distance and dihedral angle constraints are used in distance-geometry and molecular dynamics computations to calculate and refine these structures.

他们将距离和二面角的约束效应运用在距离几何学和分子动力学的计算中使其对分子结构的测定更为精确。

The two extreme structures --- and others with intermediate dihedral angle --- do exist, if one considers an instantaneous time scale.

这两个极端的结构---和其他中间二面角---确实存在，如果考虑到瞬间的时间尺度。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。