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排序方式: 共有746条查询结果,搜索用时 15 毫秒
741.
R. Ramakrishnan Somashekhar S. Hiremath M. Singaperumal 《Journal of Mechanical Science and Technology》2012,26(5):1321-1331
As gasoline prices rise and the green movement grows, more fluid power companies are working to develop hydraulic hybrid drive trains for large trucks to passenger cars and wind turbines. The hydraulic hybrid drive system is more effective and efficient than traditional hybrid systems because the quantum of recuperation energy generated is comparatively very high. Series hydraulic hybrid system specially designed for stop-and-go vehicles captures energy as the vehicle brakes and puts the vehicle in motion, when the vehicle is restarted. Then the engine kicks in, once the energy captured gets depleted. The kinetic energy lost as heat energy during mechanical friction braking is recovered and stored in the hydraulic accumulator as potential energy during hydrostatic regenerative braking. This paper gives an insight in to the dynamic simulation results obtained using LMS AMESim tool and effect of various system parameters like pre-charge pressure and hydraulic pump/motor maximum displacement on system output power. Varying the pre-charge pressure of the accumulator and controlling the hydraulic pump/motor maximum displacement show significant improvement in the system output power. Maximizing the system output power indirectly leads to less fuel consumption and pollution reduction in hybrid vehicles. 相似文献
742.
743.
Dr. Anil Karbhari Shinde Dr. Rajesh Kumar Badange Veena Reballi Pramod Kumar Achanta Kumar Bojja Sravanthi Manchineella Nageswara Rao Muddana Ramkumar Subramanian Raghava Choudary Palacharla Vijay Benade Dr. Pradeep Jayarajan Jagadeesh Babu Thentu Bujji Babu Lingavarapu Sivasekhar Yarra Narendra Kagita Mallikarjuna Rao Doguparthi Dr. Abdul Rasheed Mohammed Dr. Ramakrishna Nirogi 《ChemMedChem》2022,17(3):e202100583
A series of chemical optimizations, which was guided by in vitro affinity at histamine H3 receptor (H3R), modulation of lipophilicity, ADME properties and preclinical efficacy resulted in the identification of 1-[2-(1-cyclobutylpiperidin-4-yloxy)-6,7-dihydro-4H-thiazolo[5,4-c]pyridin-5-yl]propan-1-one ( 45 e ) as a potent and selective (Ki=4.0 nM) H3R inverse agonist. Dipsogenia induced by (R)-α-methylhistamine was dose dependently antagonized by 45 e , confirming its functional antagonism at H3R. It is devoid of hERG and phospholipidosis issues. Compound 45 e has adequate oral exposures and favorable half-life in both rats and dogs. It has demonstrated high receptor occupancy (ED80=0.22 mg/kg) and robust efficacy in object recognition task and, dose dependently increased acetylcholine levels in brain. The sub-therapeutic doses of 45 e in combination with donepezil significantly increased acetylcholine levels. The potent affinity, selectivity, in vivo efficacy and drug like properties together with safety, warrant for further development of this molecule for potential treatment of cognitive disorders associated with Alzheimer's disease. 相似文献
744.
Mahendran Logesh Arumugam Marimuthu Jose M. F. Ferreira Praveen Ramakrishnan Anbalagan. M. Ballamurugan 《Journal of the American Ceramic Society》2023,106(6):3843-3852
This work reports on a novel approach to deposit composite coatings based on biphasic calcium phosphate (BCP) incorporating graphene oxide (GO) on 316L stainless steel (316L SS) and on its protective nature against corrosion in the simulated body fluid (SBF). For this purpose, 2-dimensional GO was successfully incorporated in 1% and 3% weight ratios as mechanical strength enhancer and pore size reducer for the prepared coatings. It was observed that upon increasing the GO content, the corrosion rate was drastically decreased when compared to pristine BCP coating. The corrosion resistance polarization results are in good agreement with the test results obtained for SBF immersion study. The size of the particles has significantly decreased, as shown by transmission electron microscopy (from 190 to 27 nm). The experimental results indicate that the composite hydroxyapatite–β-tricalcium phosphate–GO (HAp–β-TCP–GO) coatings enhanced the corrosion resistance of the surgical grade 316L SS, turning it a better implanting option for orthopedic applications. 相似文献
745.
Ramasamy Santhosh Kumar Sampath Prabhakaran Shanmugam Ramakrishnan S. C. Karthikeyan Ae Rhan Kim Do Hwan Kim Dong Jin Yoo 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(20):2207096
Zinc-air batteries are gaining popularity as viable energy sources for green energy storage technologies. The cost and performance of Zn-air batteries are mostly determined by the air electrodes in combination with an oxygen electrocatalyst. This research aims at the particular innovations and challenges relating to air electrodes and related materials. Here, a nanocomposite of ZnCo2Se4@rGO that exhibits excellent electrocatalytic activity for the oxygen reduction reaction, ORR (E1/2 = 0.802 V), and oxygen evolution reaction, OER (η10 = 298 mV@10 mA cm−2) is synthesized. In addition, a rechargeable zinc-air battery with ZnCo2Se4@rGO as the cathode showed a high open circuit voltage (OCV) of 1.38 V, a peak power density of 210.4 mW cm−2, and outstanding long-term cycling stability. The electronic structure and oxygen reduction/evolution reaction mechanism of the catalysts ZnCo2Se4 and Co3Se4 are further investigated using density functional theory calculations. Finally, a perspective for designing, preparing, and assembling air electrodes is suggested for the future developments of high-performance Zn-air batteries. 相似文献
746.
Usha C. Vimala P. Ramkumar K. Ramakrishnan V. N. 《Journal of Computational Electronics》2022,21(1):181-190
Journal of Computational Electronics - We use the superposition method to model the electrostatic characteristics of a high-k stacked gate-all-around heterojunction tunneling field-effect... 相似文献