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民国时期旅渝者的重庆旅游意象研究

重庆三峡学院学报 2015年第2期31卷 36-40,57页

作者：吴大素西南大学西南历史地理研究所重庆北碚400715

民国时期的重庆,在20世纪30年代之前,基本处于国人视角的边缘位置,被外界视为蛮荒之地。30年代后的重庆逐渐进入大众视野,作为抗战陪都,大批川外人士入驻重庆,重庆一时成为国人舆论核心。根据民国时期来渝旅行的游记和文人笔记小说资料... 详细信息

民国时期的重庆,在20世纪30年代之前,基本处于国人视角的边缘位置,被外界视为蛮荒之地。30年代后的重庆逐渐进入大众视野,作为抗战陪都,大批川外人士入驻重庆,重庆一时成为国人舆论核心。根据民国时期来渝旅行的游记和文人笔记小说资料,窥视当时来渝旅行者对重庆的旅游意象和地域评价,发现旅客对重庆意象要素不断丰满全面,由负面认知逐渐向积极正面转变。因时代赋予的"民族复兴根据地"使得民国时期的重庆旅游意象具有激昂的民族情感。

关键词：民国游记重庆旅游意象

Temperature and pH Dependent Deactivation of Cutinases from Thermobifida fusca: A Comparative study of Homologous Enzymes

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Modern Research in Catalysis 2014年第4期3卷 128-135页

作者： Krishnamoorthy Hegde Venkata dasu Veeranki Biochemical Engineering Laboratory Department of Biotechnology Indian Institute of Technology Guwahati Guwahati India

Thermostability of two homologous cutinases, Cut1 and Cut2 from Thermobifida fusca NRRL B-8184 was inves-tigated at combination of different pH and temperature in the range of pH 6 - 9 and temperature 45℃ - 80℃, re-spectively. The deactivation rate constants, the half-life and thermodynamic parameters, viz., △H*, △s*, △G* and activation energy kinetics of inactivation of the cutinases were assessed at different combinations of pH and temperature and compared. The optimal pH and temperature for the least degree of deactivation for Cut1 and Cut2 were found to be 8℃ and 45℃, respectively. The deactivation process was found to be faster at pH 6 and 9, with minimum deactivation at pH 8 for both the cutinases. It was found that △s* values are negative for both the enzymes and △H* value of Cut2 was 1.5 fold higher than that of Cut1 in the range of pH studied. Cut2 was found to be thermodynamically more stable with 1.7 fold higher deactivation energy at pH 6 and 7 and 1.4 fold higher deactivation energy at pH 8 and 9 in comparison to Cut1.

关键词： Cutinase Thermal Deactivation Thermostability Thermodynamics

Batch, Fed Batch production and Characterization of Glutaminase Free L-Asparaginase II of pectobacterium carotovorumMTCC 1428 in Escherichia coli

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Advances in Microbiology 2014年第10期4卷 667-680页

作者： Rachna Goswami Krishnamoorthy Hegde Venkata dasu Veeranki Biochemical Engineering Laboratory Department of Biotechnology Indian Institute of Technology Guwahati Guwahati Assam India

The present study describes the production optimization of recombinant L-asparaginase II of pectobacterium carotovorum MTCC 1428 in Escherichia coli BL21 (DE3) at batch and fed batch bioreactor level. production of recombinant L-asparaginase II in batch and fed batch mode was found to be 1.34 and 5.38 folds higher, respectively as compared to shake flask culture. sDs-pAGE and native pAGE of the purified enzyme revealed that molecular mass of the subunits and native enzyme are ~37.5 kDa and ~150 kDa, respectively. Optimum range of pH and temperature for hydrolysis of L-asparagine were found to be 7.5 - 8.5 and 47°C - 52°C, respectively. The recombinant enzyme is very specific for its natural substrate, L-asparagine. The activity of recombinant L-asparaginase II is improved by mono cations and diverse effectors including Na+, K+, L-cystine, L-histidine, glutathione and 2-mercaptoethanol whereas, it is moderately inhibited by different divalent cations and thiol group blocking reagent. The kinetic parameters Km, Vmax, kcat and Km/Kcat of purified recombinant L-asparaginase II were determined. The purified L-asparaginase II possesses no partial glutaminase activity, which is prerequisite to reduce the possibility of side effects during the course of anti-cancer therapy.

关键词： Batch Fermentation Fed-Batch Fermentation Recombinant L-Asparaginase II Taguchi’s Method

Design of a robust pID-pss for an uncertain power system with simplified stability conditions

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protection and Control of Modern power systems 2020年第1期5卷 222-237页

作者： Vijaya Lakshmi A.s.V Ramalinga Raju Manyala siva Kumar Mangipudi Department of EEE G.V.P College of Engineering for WomenVisakhapatnamIndia Department of EEE JNTU KakinadaKakinadaIndia Department of EEE Gudlavalleru Engineering CollegeGudlavalleruAndhra PradeshIndia

In a deregulated power system uncertainty exists and lack of sufficient damping can lead to Low FrequencyOscillations (LFO). The problem can be addressed using robust power system stabilizers (pss). In this paper, anoptimal procedure to design a robust pID-pss using interval arithmetic for the single Machine Infinite Bus (sMIB)power system is proposed. The interval modelling captures the wide variations of operating conditions in boundsof system coefficients. In the proposed design procedure, simple and new closed loop stability conditions for ansMIB interval system are developed and are used to design an optimum pID-pss for improving the performance ofan sMIB system. The optimum pID-pss is attained by tuning the parameters using the FMINCON tool provided inMATLAB. The robustness of the proposed pID-pss design is validated and compared to other notable methods inthe literature when the system is subjected to different uncertainties. The simulation results and performance errorvalues show the effectiveness of the proposed robust pID-pss controller.

关键词： Low frequency oscillations Uncertainty power system stabilizer Robust controller Interval systems