正链

By using statistical analysis to the economical efficiency of fish yield in three kinds of rearing techniques,following results were octained:(1)The technique of one rearing cycle per year in polyculture with Grass Carpand Silver Carpas the main species could be considered the advanced technique of pond adult fish culture.

通过各种饲养技术不同鱼产量的经济核算结果的比较分析，证明草鱼与白链为主的单季饲养技术是经济效益较高、生产可行性较好的优势技术，应作为池塘成鱼饲养的发展重点。在一定范围内亩净利润与亩净产呈紧密正相关，为了提高池塘成鱼饲养的经济效益，生产上应推行亩净产300-1000公斤的高产技术。

In the present dissertation, a surfactant-templated mesoporous silica molecular sieve with high pore volume, high porosity and narrow bimodal mesopore size distribution was synthesized for the first time in a reaction system, which was used usually in the synthesis of mesoporous MCM-41 molecular sieves, by a judiciously controlled two-phase sol-gel processing under basic conditions.

在本论文中，我们通过对一个通常用于制备介孔MCM-41分子筛的反应体系中正硅酸乙酯水解与缩合反应相对速率的精确调控，首次在弱碱性体系中合成了一种具有高孔隙率、大孔体积和双介孔孔分布特征的新型二氧化硅分子筛材料，简记为BMS，并对BMS二氧化硅分子筛中双介孔结构形成的原因及各种可能对其结构和性质产生影响的合成因素如Ammonia／silica摩尔比、组分浓度的变化、表面活性剂烷基链长度的调节、辅助有机物均三甲苯的引入、催化剂的结构和性质、溶剂和助溶剂的极性和用量、老化和干燥条件的变化及合成后水热处理等，利用不同的测试手段如XRD，SEM，TEM，〓Si MAS NMR，TG-DTA，N〓吸附测试等进行了系统的表征研究。

Designating an aliphatic hydrocarbon having a straight and unbranched chain of carbon atoms.

正的：指定脂肪族碳氢化合物含有一直且无分枝的碳原子链

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。