辽宁美术出版社部分新书介绍

《关东剪纸》剪纸是我国最普及最具群众基础的民间艺术,它表现了浓厚的民族民间艺术特色,装饰画的艺术规律和法则蕴涵之中,是流传至今内容最丰富、数量最大的装饰体系。此书历经三年征集了百余名作者的作品,精选了500多幅。这些作品题材广泛,以古代人物、戏曲人物、现代人物、吉祥人物到生肖、动物、花鸟鱼虫、窗花等。技法上形式多样,有剪纸、刻纸、撕纸等,运剪如神,技艺精纯。或粗犷、或细腻,夸张变形,阴阳对比风格多样。

Expression Pattern of Chlamys farreri sox2 in Eggs, Embryos and Larvae of Various Stages

The SOX2 protein is an important transcription factor functioning during the early development of animals. In this study, we isolated a full-length c DNA sequence of scallop Chlamys farreri sox2, Cf-sox2 which was 2194 bp in length with a 981 bp open reading frame encoding 327 amino acids. With real-time PCR analysis, it was detected that Cf-sox2 was expressed in unfertilized oocytes, fertilized eggs and all the tested embryos and larvae. The expression level increased significantly(P < 0.01) in embryos from 2-cell to blastula, and then decreased significantly(P < 0.01) and reached the minimum in umbo larva. Moreover, location of the Cfsox2 expression was revealed using whole mount in situ hybridization technique. Positive hybridization signal could be detected in the central region of unfertilized oocytes and fertilized eggs, and then strong signals dispersed throughout the embryos from 2-cell to gastrula. During larval development, the signals were concentrated and strong signals were restricted to 4 regions of viscera mass in veliger larva. In umbo larva, weak signals could be detected in regions where presumptive visceral and pedal ganglia may be formed. The expression pattern of Cf-sox2 during embryogenesis was similar to that of mammal sox2, which implied that Cf-SOX2 may participate in the regulation of early development of C. farreri.

扇面美人

无论是造物的安排，还是冥冥中早有的定数，当女人们站在年华背后偷偷地抽噎，有人说这是命，因为命中注定。

Influence of Coanda surface curvature on performance of bladeless fan

The unique Coanda surface has a great influence on the performance of bladeless fan.However,there is few studies to explain the relationship between the performance and Coanda surface curvature at present.In order to gain a qualitative understanding of effect of the curvature on the performance of bladeless fan,numerical studies are performed in this paper.Firstly,three-dimensional numerical simulation is done by Fluent software.For the purpose to obtain detailed information of the flow field around the Coanda surface,two-dimensional numerical simulation is also conducted.Five types of Coanda surfaces with different curvature are designed,and the flow behaviour and the performance of them are analyzed and compared with those of the prototype.The analysis indicates that the curvature of Coanda surface is strongly related to blowing performance,It is found that there is an optimal curvature of Coanda surfaces among the studied models.Simulation result shows that there is a special low pressure region.With increasing curvature in Y direction,several low pressure regions gradually enlarged,then begin to merge slowly,and finally form a large area of low pressure.From the analyses of streamlines and velocity angle,it is found that the magnitude of the curvature affects the flow direction and reasonable curvature can induce fluid flow close to the wall.Thus,it leads to that the curvature of the streamlines is consistent with that of Coanda surface.Meanwhile,it also causes the fluid movement towards the most suitable direction.This study will provide useful information to performance improvements of bladeless fans.

Quasi Normal Sectors and Orbits in Regular Critical Directions of Planar System

This paper deals with the qualitative behavior of orbits at degenerate singular point with the method of quasi normal sector, which is a generalization of Frommer's normal sectors. Several examples show that this method is more effective than the wellknown methods of Z-sectors, normal sectors and generalized normal sector.

A manifold approach to generating iso-scallop trajectories in three-axis machining

A novel approach of iso-scallop trajectory generation for smooth manifold surfaces has been developed. Firstly,by defining homeomorphism mapping relations and differentiable structures,the smooth manifold surface is mapped into several Euclidean planes,thus its trajectory generation can be decomposed into planar curve-filling tasks. Secondly,in the generation of direction-parallel trajectories,the calculation of the cutting interval and the curvature is given,depending on the generation of the first curve in the projection view. Thirdly,after automatic adherences of inverse projection curves,the filled curves are mapped into the original surface inversely to form trajectories. Although the required trajectories are iso-scallop,the trajectory intervals are variable according to the curvature changes at the projection point,which is advantageous to improving the trajectory quality. The proposed approach has appealing merits of dimensionality reduction,which decreases the algorithm complexity. Finally,numerical and machining examples are given to illustrate its feasibility and validity.