成对比较

Objective: To evaluate the fracture strengths of treated teeth with prefabricated post with different materials.

目的：对不同材质预成桩修复离体牙根后的抗折性能进行比较。

F-10B in the structure is basically designed to develop into a carrier-based fighters with the basic conditions, structure, aerodynamic and performance is also better balances the needs of carrier aircraft, but the single fighter to improve the structure of growth for the carrier aircraft re-issue of it is difficult to eliminate, J -10 with the AL-31FN engines on the J--10 There is just another shortcoming of lack of thrust.

歼-10B在结构设计上基本上具备了发展成舰载战斗机的基础条件，结构、气动和性能方面也比较好的均衡了舰载机的需要，但单发战斗机改进为舰载机的结构增重问题的影响却很难消除，歼-10采用的AL-31FN发动机对歼-10来说恰恰又存在推力不足的缺陷。

The traditional query tree optimization methods,parallel database optimization methods based on left linear trees and right linear trees,bushy trees,and operation of the forest,have their own pros and cons,they have been more in-depth and maturity of the study.The query optimization method based on multiple weighted tree has studied its model of parallel query plan,its complexity model of parallel query plan and query optimization algorithms.The semantic query method transforms an inquiry into one or several semantic equivalence inquiries then has to find and implement a strategy to achieve a better query.Agent-based parallel database query optimization using Multi-Agent technology to automatically search the integrity constraint conditions which are related to the determined query,there for,the efficiency between several relations' joins has been greatly improved.The parallel optimization algorithm,based on genetic algorithm which is suitable for multi-joins of cluster environment,has deeply studied the relations storage options,multi-joins query optimization and query processing and other key technologies based on cluster parallel database.

传统的查询树优化方法，即基于左线性树、右线性树、浓密树、操作森林的并行数据库查询优化方法，各有优劣，对其的研究比较深入、成熟；基于多重加权树的查询优化方法，研究了其并行查询计划模型、并行查询计划的复杂性模型和查询优化算法；语义查询优化方法将一个查询变换成一个或数个语义等价的查询，进而寻找并执行这些等价查询中具有较好实现策略的一个；基于Agent的并行数据库查询优化采用Multi-Agent技术自动查找与给定查询有关的完整性约束条件，使得多个关系间连接操作的效率得到很大的提高；基于遗传算法的并行优化算法，深入研究了基于机群并行数据库中关系存储的选择、多连接查询优化和查询处理等关键技术。

Being supported by Hebei Kangli Animal Pharmaceutical Co., Ltd., and based on the research object, coccidiosis, which damages to livestock breeding heavily, this project has developed QIULIKE--an oral liquid of pure traditional Chinese medicine compounded with 7 Chinese medicinal herbs such as Dichroa febrifuga, southernwood and Sophora flavescens Ait., ect. The aim of the project is to solve the problem of present heavy residual quantity of anti-coccidiosis agent in order to meet the people's increasing requirement for "pollution-free" food.

本项目以河北康利动物药业有限公司为依托，以危害养殖业比较严重的球虫病为研究对象，研制出以常山，青蒿，苦参等7位中药配伍而成的球立克口服液，旨在解决目前抗球虫药残留量大的难题，更好地满足人们对"绿色"食品与日俱增的需求。

The cloned BBE gene sequences were 94.84% identified with the reported BBE genes in GenBank previously. Based on the cDNA sequences of COR and BBE ,two fragments about 400～500 bp from each gene with lower identity among them were cloned. The fusion gene BC (744 bp) is fused by the PCR technique. Then the promoter CaMV 35S driven, containing'forward BC fusion fragments-reverse pdk intron-reverse BC fusion fragments', plant siRNA expression vector were constructed based on the vectors pHANNIBAL and pART27.The work will lay the foundation for breeding a low morphine and high thebaine poppy.

利用blast及分子生物学软件DNAStar对COR和BBE基因的cDNA序列同源性进行分析比较，分别从各基因中筛选和克隆了一段同源性极低、约400～500 bp的片段；并应用重叠PCR法将其拼接成744 bp的融合基因BC，以中间载体pHANNIBAL和植物表达载体pART27为基础，构建了以CaMV 35S启动子驱动的含有"正向BC融合片段- pdk内含子-反向BC融合片段"的ihRNAi植物表达载体，通过转化野生罂粟，初步研究了以COR和BBE基因为靶标的RNAi对内源吗啡合成的抑制效果，为进一步培育低吗啡高蒂巴因的罂粟种质提供了依据。

Density functional theory calculations have been carried on the molecular knot at the RB3LYP/6-31G levels. Based on the optimized geometry, the vibrational spectra, natural bond orbital and orbital energy level analysis for C30 carbyne trefoil knot have been calculated at the same level, and compared with the cyclo-C30 carbyne molecule.

本文用密度泛函方法[DFT/RB3LYP/6-31G]对分子结构和光谱性质进行了研究，在优化构型的基础上通过自然键轨道方法和轨道能级研究了它的共轭性、成键情况和稳定性，并与平面型C30卡宾环分子进行了比较。

In order to compare the tribological properties of two aluminum matrix composites reinforced by different content of B4C particles ,the pin samples were prepared with them and friction and wear tests of pin-on-steel disc were carried out on a multifunctional tribometer.

为了比较两种含量不同的碳化硼颗粒增强铝基复合材料的摩擦学性能，将其加工成销试样，在多功能摩擦磨损试验机上分别与钢盘试样进行对比摩擦磨损试验，重点研究了接触载荷和相对滑动速度对两种复合材料摩擦磨损性能的影响。

Via comprehensive computations, the possibilities of vinylidene and allene intermediates were excluded, and the reaction mechanism was found to contain the following three steps:(1) gold-catalyzed cyclization to give the cyclic intermediate,(2) the cyclic intermediate undergoing a 1,3-H migration to give a more stable intermediate, with the assistance of water-cluster,(3) finially, the 1,2-H or 1,2-silyl migration occuring for generation of the observed product.

通过对各种可能的反应路径的进行计算和比较，排除了亚甲基卡宾和连二烯中间体的可能性，并确定该异构化反应机理包含以下三个步骤：（1）炔丙基吡啶反应在金催化条件下发生分子内的成环得到环状中间体；（2）环状中间体在水分子簇的协助下优先发生1，3-氢迁移反应，异构化得到更为稳定的中间体；（3）最后再进行1，2-氢迁移或是1，2-硅烷基团迁移即得到实验中所观察到的环异构化产物。

It is also related to my understanding of painting. For me, painting is a word, a memory. My thoughts and actions, or a certain purpose born out of it, or a certain reason are what I consider in painting. This assembly of things could appear to be rather absurd at times.

再有我对绘画的认识，绘画于我来说是一个词，一个记忆，由它生发的以后的想和做，或某种目的性，某种理由，我都把它们理解成绘画，这种综合有时展示出来是比较荒唐的。1

This experiment use chitosan and combination antistaling agent,which made from kinds of antiputrefactive frequent,to do the film coating deal on eggs .

实验采用壳聚糖及几种比较常见的防腐剂配制成复合保鲜剂，分别对鸡蛋进行涂膜处理，常温贮藏20 d并观察壳聚糖及其复合保鲜剂的保鲜效果。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。