http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Pravin Kumar Singh (검색결과 6 건)
- 무료
- 기관 내 무료
- 유료
-
Optimization of vibratory welding process parameters using response surface methodology
Pravin Kumar Singh,S. Deepak Kumar,D. Patel,S. B. Prasad 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.5
The current investigation was carried out to study the effect of vibratory welding technique on mechanical properties of 6 mm thick butt welded mild steel plates. A new concept of vibratory welding technique has been designed and developed which is capable to transfer vibrations, having resonance frequency of 300 Hz, into the molten weld pool before it solidifies during the Shielded metal arc welding (SMAW) process. The important process parameters of vibratory welding technique namely welding current, welding speed and frequency of the vibrations induced in molten weld pool were optimized using Taguchi’s analysis and Response surface methodology (RSM). The effect of process parameters on tensile strength and hardness were evaluated using optimization techniques. Applying RSM, the effect of vibratory welding parameters on tensile strength and hardness were obtained through two separate regression equations. Results showed that, the most influencing factor for the desired tensile strength and hardness is frequency at its resonance value, i.e. 300 Hz. The micro-hardness and microstructures of the vibratory welded joints were studied in detail and compared with those of conventional SMAW joints. Comparatively, uniform and fine grain structure has been found in vibratory welded joints.
-
Development of male sterile transgenic lines in rice by tapetum specific expression of barnase gene
Pravin Kumar,Kulwinder Kaur,Ram Singh Purty,Madan Mohan,Pradeep Kumar Burma 한국식물생명공학회 2017 JOURNAL OF PLANT BIOTECHNOLOGY Vol.44 No.4
The key to development of barnase-barstar transgene based hybrid seed technology is the availability of tightly regulated tapetum specific promoter, as any leaky expression of the barnase gene leads to several unintended effects. In the present study, we used two different tapetum specific promoters i.e. promoter of the RTS gene isolated from rice cultivar IR64 and the OsG6b promoter from japonica rice cultivar Hayayuki to express the barnase gene in rice transgenic lines. While viable male sterile transgenic lines could not be obtained with RTS promoter we could develop single copy male sterile lines when the barnase gene was expressed under the OsG6b promoter.
-
Development of male sterile transgenic lines in rice by tapetum specific expression of barnase gene
Kumar, Pravin,Kaur, Kulwinder,Purty, Ram Singh,Mohan, Madan,Burma, Pradeep Kumar The Korean Society of Plant Biotechnology 2017 식물생명공학회지 Vol.44 No.4
The key to development of barnase-barstar transgene based hybrid seed technology is the availability of tightly regulated tapetum specific promoter, as any leaky expression of the barnase gene leads to several unintended effects. In the present study, we used two different tapetum specific promoters i.e. promoter of the RTS gene isolated from rice cultivar IR64 and the OsG6b promoter from japonica rice cultivar Hayayuki to express the barnase gene in rice transgenic lines. While viable male sterile transgenic lines could not be obtained with RTS promoter we could develop single copy male sterile lines when the barnase gene was expressed under the OsG6b promoter.
-
Pravin Kumar,Ram Singh Purty 한국작물학회 2021 Journal of crop science and biotechnology Vol.24 No.5
The indispensable requirement for the barnase–barstar based hybrid seed production technology is the availability of a tightly regulated tapetum-specifc promoter. Until now, the specifcity of literature reported tapetum-specifc promoters are mainly characterized based on the fusion of non-lethal GUS/GFP gene as promoter–reporter fusion approach. In our previous report, the tapetum-specifc OsG6b promoter had successfully generated 100% male sterile barnase line, whereas the OsRTS promoter (from indica rice cultivar IR64) was leaky in nature. In continuation, our observation with another two tapetum-specifc promoters is reported here. Two distinct phenotypes with no male sterility were observed in the OsFbox promoter barnase lines due to leaky expression, whereas almost half of the OsYY2 promoter lines were male sterile. Based on our results, it is clear that the tapetum-specifc promoters characterized based on the fusion of non-lethal GUS/GFP gene regulate the non-specifc lethal barnase gene diferently. Therefore, the ideal way of characterizing the tapetum-specifc promoter for hybrid seed production should be a lethal gene such as barnase instead of non-lethal GUS/GFP gene
-
Pravin Kumar Ray,Devesh Chandra Bharati,J. P. Singh,A. L. Saroj 한국고분자학회 2023 Macromolecular Research Vol.31 No.6
Carboxymethyl cellulose (CMC) + xwt% Ethylenediaminetetraacetic acid (EDTA) (x = 0, 10, 20, 30, 40)-based biopolymer electrolytes (BPEs) plasticised with polyethylene glycol (PEG) were prepared by using solution cast method. Fourier transform infrared (FTIR) spectroscopic analysis shows the complexation of salt, EDTA with the functional groups of CMC. Impedance analysis shows that the sample containing 20wt%EDTA has the optimum dc conductivity ~ 8.95 × 10–5 S/cm at 30 °C with least activation energy ~ 0.25 eV. Temperature-dependent dc conductivity, dielectric properties and ion dynamics have been analyzed to explore the ion transport mechanism. The scaling of frequency-dependent conductivity and loss tangent were analyzed with respect to EDTA concentration and temperatures. Mobility (µ), charge carrier density (N) and ion diffusivity (D) for all samples were estimated and the sample containing 20wt% EDTA shows the optimum values. Ionic transference number (ITN) measurements reveal that ions are the principal charge carriers. Electrochemical stability window (ESW) was found to be ~ ± 2 V for 20wt% EDTA containing sample.
-
Comprehensive Loss Analysis of Isolated Bidirectional Matrix based AC-DC Converter
Prathamesh Pravin Deshpande,Amit Kumar Singh,Hau Chong Aih,Merlin Chai,Sanjib Kumar Panda 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5
In this paper a comparison of traditional two stage back-to-back AC-DC converter with matrix based ACDC converter using comprehensive loss analysis is presented. The two-stage AC-DC converter uses a boost rectifier with power factor correction at the grid side while a full bridge converter at the load end. A current control based closed loop control is developed for the grid end converter while synchronous rectification is used for the corresponding half when full bridge converter is operated in the bidirectional mode. Matrix based AC-AC converter eliminates the use of DC-link and hence the bulky DC link capacitor. Space Vector Modulation based switching scheme is used for matrix based single stage converter. As, the matrix based converter uses back-to-back switches, it contributes to maximum proportion of the total loss followed by input LC filter and controlled rectifier part of the AC-DC converter. Maximum efficiency calculated is about 95.5 % for the matrix based converter, while for two stage converter is about 80 %. Matrix based converter provides higher efficiency, power density, reliability, etc.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
