2,4 D Regulated Somatic Embryogenesis of Sweet Potato

将来源于‘徐薯18’叶片的胚性愈伤组织，接种在含有不同2，4d浓度的液体MS培养基中进行悬浮培养，悬浮细胞表现出不同的形态结构、分裂方式和发育途径：2，4d浓度为1Mg/l时，细胞均等分裂，增殖迅速；不含2，4d时，细胞多进行不均等分裂，并发育成体细胞胚。不同2，4d浓度中培养的悬浮细胞，其胞外过氧化物同工酶谱及其随时间变化的方式有很大差异，并与细胞的生长、发育过程密切相关Divergences were discovered in cell morphology, mode of cell division and passage of cell differentiation, when embryogenic calli induced from leaves of `Xushu 18' sweet potato were suspension_cultured in modified MS medium with different concentrations of 2,4 D.Cells grew quickly and divided equally in medium containing 1 mg/L 2,4 D.When 2,4 D was deleted, the cells divided unequally and developed into embryos.Extracellular peroxidase isozyme patterns changed greatly during suspension culture with different concentrations of 2,4 D and were closely related to cell development process

Application of Bachmann PLC in Wind Turbine Control System

It is significant that the application of PLC in wind turbine control system. This paper introduces the implementation of Bachmann PLC in wind turbine control system, and then analyzes the hardware and software of control system based on Bachmann PLC. Furthermore, the functions and states of main control software as well as failures and alarms of wind turbine are described

不同飞行高度下超声速来流/射流及其相互作用的数值模拟

采用高精度格式求解二维Navier-Stokes方程,研究了不同飞行高度下超声速来流和射流在后台阶相互作用的流场基本结构.时间推进采用三阶精度Runge-Kutta格式,分别应用五阶精度加权本质无振荡(weighted essentially non-oscillatory,WENO)格式、六阶精度中心差分格式来离散对流项和粘性项,并应用MPI非阻塞式实现并行化.采用两步后台阶模型分别研究了不同高度下超声速后台阶流动、射流的基本结构特征;并进一步组合两种流动,研究了超声速来流/射流组合流动下相互作用的流场结构.通过改变后台阶上方来流条件,模拟了不同飞行高度的环境,研究了其对流场中涡、剪切层、激波等结构的影响.研究结果发现,超声速来流和射流发生相互作用后,在后台阶附近产生回流区,超声速来流的存在会对射流的流场结构产生影响

射流与超声速来流剪切层作用的数值模拟研究

本文采用高精度格式求解二维Navier-Stokes方程，分别应用五阶WENO格式、六阶中心差分格式离散对流项和黏性项，时间推进采用三阶Runge-Kutta格式，并应用MPI非阻塞式通信进行并行计算，模拟了超声速射流与同向超声速流动的相互作用，目的在于研究流长产生的两个剪切层的相互作用，发现了有一定夹角的剪切层作用产生周期性次生射流的现象。本文研究了射流／超声速流剪切层相互作用、作用产生的次生射流具有脉冲性等方面，着重对次声射流的周期性等展开分析和讨论

OPTIMIZATION of TUNNEL JUNCTION IN IMM MULTI-JUNCTION SOLAR CELLS

利用MOCVd设备进行倒装多结III-V族半导体化合物太阳电池隧穿结的外延优化。利用Xrd和SEM对样品进行结构分析,结果表明样品晶格质量较高,晶格匹配度良好;通过芯片工艺后,获得所需太阳电池片,I-V电学测试结果表明隧穿结带隙、厚度和掺杂是影响隧穿效应的重要因素。在隧穿结区厚度为40nM时掺杂浓度P型高达7x1019CM-3,n型高达3x1019CM-3条件下,隧穿结峰值电流能满足1000倍聚光条件下大隧穿电流的要求。在未蒸镀减反射层时,AM1.5d、1000倍聚光、25℃、lOW-AOd条件下,测得倒装双结太阳电池的VOC=2.776V,ISC=10.63A,ff=82.4%,Eff=24.27%。The MOCVD epitaxial growth process of the tunnel junctions in IMM solar cells was studied.After the growth,the structural analysis as XRD and SEM show the high crystal quality of the epi-layers.I-V measurement indicates that tunnel effects strongly depend on the thickness, band gap and the doping level of the tunnel junction.When the thickness is 40nm,the carrier concentration of the p region is above 7 × 1019cm- 3and n region is above 3 × 1019cm- 3,the peak current of the tunnel junction can meet the current requirement of the triple junction solar cell under the 1000 suns.Without the ARC,under 1000 suns,AM1.5D,25℃,Low-AOD conditions,the inverted dual junction solar cell get the Voc= 2.776V,Isc= 10.63A,FF = 82.4%,Eff = 24.27%.国家高技术研究发展(863)计划(2012AA051402