In this article several control schemes for a pilot scale polymerization reactor are proposed and one of them is selected as the most suitable design. The performances of proposed schemes have been compared through computer simulations. The controllers are PID and Chosen reaction is polymerization of methyl methacrylate which is highly exothermic.

Understanding how biotic mechanisms confer stability in variable environments is a fundamental quest in ecology, and one that is becoming increasingly urgent with global change. Several mechanisms, notably a portfolio effect associated with species richness, compensatory dynamics generated by negative species covariance and selection for stable dominant species populations can increase the stab...

The Yarlung Zangbo River basin is an important alley to transport moisture from the Indian Ocean to the inner Tibetan Plateau. With a wide range of elevations from 147 m to over 7000 m above sea level (a.s.l.), ecosystems respond differently to climate change at various elevations. However, the pattern of elevation-dependent vegetation change and how it responds to recent warming have been rare...

polymerization, a large change in conformation, or a combination of both (2, 3). The control Bence Jones protein had 2 molecular species that were consistent with monomer and dimer in the presence or absence of physiologic concentrations of salt. Sedimentation equilibrium experiments were performed on the cryo -light chain protein that had been preequilibrated in the no-salt buffer and run at 6...

The effect of desert dust on cloud properties and precipitation has so far been studied solely by using theoretical models, which predict that rainfall would be enhanced. Here we present observations showing the contrary; the effect of dust on cloud properties is to inhibit precipitation. Using satellite and aircraft observations we show that clouds forming within desert dust contain small drop...

*National Institute of Information and Communications Technology, Tokyo, Japan +Meteorological Research Institute, Ibaraki, Japan #Hokkaido Tokai University, Hokkaido, Japan @Tokyo Metropolitan Institute of Technology, Tokyo, Japan &Osaka Prefecture University, Osaka, JAPAN **Japan Aerospace Exploration Agency, Tokyo, Japan ++Shimane University, Shimane, Japan ##Center for Climate System Resear...

INTRODUCTION Polymer/clay nanocomposites, in which nanosized silicate plates of clay are uniformly dispersed in the polymer matrix, provide enhanced mechanical and thermal properties compared to conventional composites. Not all polymer and clay combinations will form nanocomposites: the compatibility and interfacial properties between polymer matrix and clay layers significantly influence the e...

ethylene polymerization was carried out using phillips chromium catalyst based on silica supports such as silicaaerogel, sio2 (grace 643), and titanium modified sio2 (g 643), and the results were compared with othercatalysts based on sio2 (aldrich), sba-15(hex), sba-15(sp) and mcm-41. a combination of tga, dsc, xrd,nitrogen adsorption, sem, icp, ftir and other analyses were used to characterize...

the main objective of the present work was to synthesis polyamide 6 through anionic polymerization of ε-caprolactam in an internal mixer. the reaction time and the rheological properties of samples during the polymerization were studied. the samples were characterized by thermo gravimetry analysis (tga), differential scanning calorimeter (dsc) and ft-ir spectrometer. the melt flow behavior and ...

The radiative and microphysical effects of aerosols can affect the development of convective clouds. The objective of this study is to reveal if the overall aerosol effects have any discernible impact on the diurnal variations in precipitation and lightning by means of both observational analysis and modeling. As the first part of two companion studies, this paper is concerned with analyzing ho...