Topological analysis of plasma flow control on corner separation in a highly loaded compressor cascade

In this paper, flow behavior and topology structure in a highly loaded compressor cascade with and without plasma aerodynamic actuation （PAA） are investigated. Streamline pattern, total pressure loss coefficient, outlet flow angle and topological analysis are considered to study the effect and mechanism of the plasma flow control on corner separation. Results presented include the boundary layer flow behavior, effects of three types of PAA on separated flows and performance parameters, topology structures and sequences of singular points with and without PAA. Two separation lines, reversed flow and backflow exist on the suction surface. The cross flow on the endwall is an important element for the comer separation. PAA can reduce the undertuming and overturning as well as the total pressure loss, leading to an overall increase of flow turning and enhancement of aerodynamic performance. PAA can change the topology structure, sequences of singular points and their corresponding separation lines. Types II and III PAA are much more efficient in controlling comer separation and enhancing aerodynamic performances than type I.

从陆地棉种子无絮突变体珠被细胞中克隆出的一个抑制基因

A fiberless seed mutant (fl) was identified in a commercial cotton ( Gossypium hirsutum L. )variety Xu-Zhou 142 (FL). This phenotype is associated with lack of fiber cell initiation in the outer integument of the ovule, as was characterized by analysis of genes related to fiber differentiation and development. ……

In vitro inhibition of pigmentation and fiber development in colored cotton

Colored cotton has naturally pigmented fibers.The mechanism of pigmentation in cotton fiber is not well documented.This experiment was conducted to study the effects of respiratory chain inhibitors,i.e.,rotenone and thiourea,on pigmentation and fiber development in colored cotton.After 1 d post-anthesis,ovaries were harvested and developing ovules were cultured on the liquid medium containing different concentrations of rotenone and thiourea for 30 d.The results demonstrate that both respiratory inhibitors reduced fiber length and ovule development under ovule culture conditions,and the inhibition efficiency of rotenone was much higher than that of thiourea.Rotenone and thiourea also showed significant effects on fiber pigment (color) development in colored cotton.In green cotton fiber,rotenone advanced fiber pigment development by 7 d at 200 μmol/L,while thiourea inhibited fiber pigmentation at all treatment levels (400,600,800,1000,and 2000 μmol/L).Both respiratory inhibitors,however,had no significant effects on pigmentation of brown cotton fibers.The activities of cytochrome c oxidase (COX) and polyphenol oxidase (PPO) decreased significantly with increasing levels of both respiratory inhibitors.It is suggested that both respiratory inhibitors have important roles in deciphering the mechanism of pigmentation and fiber development in colored cotton.