The Properties of Synthetic Amylopectin with Long External-Chains

Samples of synthetic amylopectins with long external chain-lengths have been prepared from degraded, waxy maize amylopectin and glucose-1-phosphate by the action of potato phosphorylase. Samples having external chain-lengths determined by enzymic assay of 23.4, 29.9, 46.5, and 109.5 glucose units (original sample = 13.7 glucose units) were prepared. The iodine-staining properties of these materials have been investigated, and a relation between λ_max and average chain-length evaluated. A theoretical relation between chain-length and β-amylolysis limit has been proposed. The iodine-binding capacity of the samples has been studied in detail by potentiometric titration at 1.5 °C and 20 °C. Unambiguous conclusions regarding the observed iodine binding capacity and the length of external chain have been made for the first time. The properties of the synthetic products are discussed.     

适用于微机电系统的自适应红外探测器的可调谐滤光器设计与开发

微机电系统与高品质红外探测技术联合运用为国防、商业、通信、生物医学检测及环境监测等许多应用领域面临的一系列具有挑战性的问题提供了唯一可行的解决方案．可调谐法布里．玻罗滤光片是适用于微机电系统的红外探测器的核心部件．滤光片的结构设计和关键结构件的材料对于滤光片的性能和整个装置的完善性有重要影响．阐述了利用有限元建模进行法布里-玻罗滤光片机械设计和分析的方法．报告了滤光片的结构材料——用低温等离子增强化学沉积法制造的氮化硅的结构表征和机械性能测定方法和结果．最后展示了一些所制作的滤光片阵列．     

Prediction of Losses in Flow Through the Last Stage of LP Steam Turbine

The aim of presented work was the prediction of the losses in the wet steam flow through the last stage of 200MW steam turbine LP part.To this end,three numerical tools were used.The first method was the streamline curvature method (SCM) used on the meridional plane with losses correlations.The next two methods,TASCflow commercial CFD code and an in-house CFD code,based on the solution of the Reynolds- averaged Navier-Stokes equations (RANS).Ap- plication of three independent numerical tools al- lowed to make the more reliable losses analysis and made possible to compare applied numerical methods with each other. For the flow modeling in the last stage of LP steam turbine the various two-phase flow models were used and compared.The equilibrium model and non-equi- librium models with homogeneous and/or heterogeneous condensation were considered.The boundary conditions at the inlet and outlet from the stage were selected in such way to get the beginning of the homogeneous condensation process in the sta- tot.It corresponded to the part load of the turbine, i.e.140MW power and pressure in condenser 2.7kPa.