缩进

The experiment gains reaction parameters of methylal from formaldehyde and methanol,it also found a mathematical model for continuous production process.

通过实验取得了甲醛和甲醇合成甲缩醛的反应参数；建立了其连续生产工艺的数学模型，利用ASPEN PLUS软件对甲醛和甲醇缩合生成甲缩醛进行了模拟，结果表明反应精馏连续生产甲缩醛的工艺是可行的，转化率高达99%，并得到含甲缩醛99%的产物，同时确定了进料板和反应区。

Functional appliance is considered the most effective device to treat mandible retrusion in nonage. By appling orthopedic force, it stimulates mandible growth and improves bimaxillary relationship.

应用功能矫治器施以矫形力促进下颌生长发育，改善上下颌骨间关系及侧貌，被认为是早期矫治下颌后缩最直接有效的途径。

Next, another novel diamine, 5-5-(4-phenyl-1,3,4-oxadiazol-2-ylbenzene-1,3-diamine, was prepared and polymerization was carried out in the same way to obtain polyimides containig triphenylamine units and 1,3,4-oxadiazole moieties in the side chain .

接下来，合成另一个新型双胺5-5-(4-phenyl-1，3，4-oxadiazol-2-ylbenzene-1，3-diamine后，以相同方法进聚缩合反应，可制得另一系列三苯胺和1，3，4-恶二唑为侧链的聚醯亚胺。

First, N'-(4-aminophenyl)-N'-4-(5-phenyl-1,3,4-oxadiazol-2-ylphenylbenzene-1,4-diamine was prepared and polymerization was carried out by direct polycondensation with a series of dianhydrides to obtain polyimides containig triphenylamine units in the main chain and 1,3,4-oxadiazole moieties as pendent group.

首先合成新型双胺N'-(4-aminophenyl)-N'-4-(5-phenyl-1，3，4-oxadiazol-2-ylphenylbenzene-1，4-diamine后，与一系的芳香族二酐进聚缩合反应，可制得一系列三苯胺为主链且1，3，4-恶二唑为侧链的聚醯亚胺。

The two Pavlograd squadrons were bivouacking in the middle of a field of rye, which was already in ear, but had been completely trodden down by the cattle and horses.

由于雨水流进了领口而缩着脖子的罗斯托夫吸着烟斗，漫不经心地听着，不时看看那位依偎着他的年轻军官伊林。

Winston Smith, his chin nuzzled into his breast in an effort to escape the vile wind, slipped

温斯顿 -史密斯缩紧了脖子躲寒风，快手快脚溜进胜利大厦的玻璃门——不过他的动作不够快，没能免得了一阵沙土打着旋儿跟在他的身后刮进门。

Winston Smith, his chin nuzzled into his breast in an effort to escape the vile wind, slipped quickly through the glass doors of Victory Mansions, though not quickly enough to prevent a swirl of gritty dust from entering along with him

温斯顿·史密斯缩紧了脖子躲寒风，快手快脚溜进胜利大厦的玻璃门——不过他的动作不够快，没能免得了一阵沙土打着旋儿跟在他的身后刮进门。

The results show that proper reentrant combustion chamber can effectively organize and control the flow distribution and intensity in the combustion chamber. There exists an optimized fuel injection position and intake swirl ratio for this kind of combustion chamber to decrease engine emission without scarifying engine power output and fuel economy.

结果表明，通过低排放缩口型燃烧室结构参数的优化，可有效地组织和控制燃烧室内气流分布规律及其强度，而且对于这种燃烧室结构存在着最佳的喷射位置和进气涡流强度，使得在动力性和经济性基本保持不变的条件下，可有效地改善柴油机的排放特性。

Also, we have shown experimentally that the optimal multi-bank Haar wavelets perform better than DCT in image compression.

同时，我们用图像缩编码的方法验证了最优多进Haar小波的性能优于离散余弦变换的。

The influences of forming parameters,such as specification of heat treatment,nominal reduction of blank radius,feed ratio and roller track,on multi-pass neck-spinning of aluminum exhausted pipe used in vehicle are researched,and sound exhausted pipe s are developed by selecting reasonable processing parameters and roller tracks.

以铝质汽车排气歧管为研究对象，探讨了热处理工艺规范、名义压下量、进给比、旋轮运动轨迹等对三维非轴对称偏心及倾斜件多道次缩径旋压成形工艺的影响，通过选择合理工艺参数及旋轮运动轨迹，研制出合格的汽车排气歧管样件。

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。