Pristine graphene-ink for 3D-printed flexible solid-state supercapacitor

Kumar Satendra,Goswami Manoj,Singh Netrapal,Soni Prachi,Sathish N.,Kumar Surender 한국탄소학회 2022 Carbon Letters Vol.32 No.4

Due to its capacity to manufacture low-cost 3D-printed structures, 3D-printing technology offers a unique opportunity for the fast epitome of various applications. Using a typical fused deposition modeling 3D printer along with a Discovery extruder, a graphene-ink can be 3D printed to produce an interdigitated electrode (IDE) arrangement. This work fabricated a 3D-printed planar supercapacitor from pristine graphene-ink without using high-temperature processing or functional additives. The printable ink (89%) is formulated from pristine graphene without the addition of any functional additives. The symmetric flexible supercapacitor is demonstrated with an excellent specific capacitance of 137.50 F/g at 0.5 A/g and an energy density of 12.23 Wh/kg. The obtained gravimetric energy density beats reported earlier carbon-based supercapacitors that are 3D or inkjet printed. The flexibility and robustness of 3D-printed devices are achieved up to 150° folding angles. This work demonstrates an efficient and easy method for fabricating practical energy storage devices featuring a customizable shape and excellent flexibility.

Propolis Reverses Acetaminophen Induced Acute Hepatorenal Alterations: A Biochemical and Histopathological Approach

Satendra Kumar Nirala,Monika Bhadauria 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.4

The present study has been conducted to evaluate the curative effect of propolis extract, a honey bee-hive product, against acetaminophen (APAP) induced oxidative stress and dysfunction in liver and kidney. Animals were challenged with APAP (2 g/kg, p.o.) followed by treatment of propolis extract (100 and 200 mg/kg, p.o.) once only after 24 h. Release of transaminases, alkaline phosphatase, lactate dehydrogenase, and serum bilirubin were increased, whereas hemoglobin and blood sugar were decreased after APAP administration. Antioxidant status in both the liver and kidney tissues were estimated by determining the glutathione, malondialdehyde content and activities of the CYP enzymes, which showed significant alterations after APAP intoxication. In addition, activities of adenosine triphosphatase, acid phosphatase, alkaline phosphatase, and major cell contents (total protein, glycogen and cholesterol) were also altered due to APAP poisoning. Propolis extract successfully reversed the alterations of these biochemical variables at higher dose. Improvements in hepatorenal histoarchitecture were also consistent with biochemical observations. The results indicated that ethanolic extract of propolis has ability to reverse APAP-induced hepatorenal biochemical and histopathological alterations probably by increasing the antioxidative defense activities due to various phenolic compounds present in it.

Propolis Reverses Acetaminophen Induced Acute Hepatorenal Alterations: A Biochemical and Histopathological Approach

Nirala, Satendra Kumar,Bhadauria, Monika 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.4

The present study has been conducted to evaluate the curative effect of propolis extract, a honey bee-hive product, against acetaminophen (APAP) induced oxidative stress and dysfunction in liver and kidney. Animals were challenged with APAP (2 g/kg, p.o.) followed by treatment of propolis extract (100 and 200 mg/kg, p.o.) once only after 24 h. Release of transaminases, alkaline phosphatase, lactate dehydrogenase, and serum bilirubin were increased, whereas hemoglobin and blood sugar were decreased after APAP administration. Antioxidant status in both the liver and kidney tissues were estimated by determining the glutathione, malondialdehyde content and activities of the CYP enzymes, which showed significant alterations after APAP intoxication. In addition, activities of adenosine triphosphatase, acid phosphatase, alkaline phosphatase, and major cell contents (total protein, glycogen and cholesterol) were also altered due to APAP poisoning. Propolis extract successfully reversed the alterations of these biochemical variables at higher dose. Improvements in hepatorenal histoarchitecture were also consistent with biochemical observations. The results indicated that ethanolic extract of propolis has ability to reverse APAP-induced hepatorenal biochemical and histopathological alterations probably by increasing the antioxidative defense activities due to various phenolic compounds present in it.

GENERALIZED LOGARITHMIC MEANS OF AN ENTIRE DIRICHLET SERIES OF ORDER ZERO (I)

Vaish, Satendra Kumar Department of Mathematics 1982 Kyungpook mathematical journal Vol.22 No.2

New europium complexes and their use in red light-emitting diodes and vapoluminescent sensors

Devi Rachna,Boddula Rajamouli,Singh Kasturi,Kumar Satendra,Vaidyanathan Sivakumar 한국정보디스플레이학회 2021 Journal of information display Vol.22 No.3

Three novel trivalent europium [Eu(III)] complexes – Eu(DBM)3Phen-Ph-Ph, Eu(DBM)3Phen-mCF3-Ph, and Eu(DBM)3Phen-pCF3-Ph – were designed, synthesized, and characterized using various spectroscopic methods. Then their photophysical characteristics were investigated. The Eu complexes in the solid phase showed a pure red emission (due to the electric dipole transitions of the Eu3+ ion). In a solution, they had multiple emissions due to their ligand contribution. The solvatochromism studies revealed that the Eu(III) complexes in the methanol and DMSO solutions had both metal ion and ligand emissions with similar intensities, which yielded a white emission. Of all the Eu(III) complexes, Eu(DBM)3Phen-mCF3-Ph showed the best quantum yield. In addition, the fluorinated mCF3 ligand had an unusually high lifetime value. Its remarkable linear decrease in luminescence intensity with increasing temperature opens a new window for its use as a sensitive temperature sensor at the 30–80°C range. The CIE color coordinates of the fabricated red LEDs (InGaN) are very close to the standard NTSC CIE color coordinates for bright red emissions, and the color purity as well as the LER values of the fabricated red LEDs are also very good. The Eu(III) complexes exhibited on-off photoluminescence switching via the vapoluminescent process and responded best to the acid-base (HCl-NH3) vapors. All these features suggest that the synthesized Eu(III) complexes are efficient candidates for red-emitting LEDs and vapoluminescent sensors. Organic chromophores, which are phenanthro-imidazole ligands based on fluorinated moieties coordinated with Eu(III) metal ions, very efficiently facilitate energy transfer from the ligand to the Eu(III) ion. The CIE color coordinates of the complexes showed a bright pure red emission, with x = 0.66 and y = 0.33 (612 nm). The fabricated light-emitting diode (LED) showed superior color quality and the complexes showed on-off-on luminescence behavior after exposure to the acid-base vapors.

Attenuation of Beryllium Induced Hepatorenal Dysfunction and Oxidative Stress in Rodents by Combined Effect of Gallic Acid and Piperine

Zhao, Jun-Quan,Du, Guo-Zhen,Xiong, You-Cai,Wen, Yi-Fu,Bhadauria, Monika,Nirala, Satendra Kumar 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.12

We determined a minimum effective dose of gallic acid (3,4,5-trihydroxy benzoic acid; 50 mg/kg, Lp.) and piperine (10 mg/kg, p.o.) through their therapeutic potential and further evaluated them individually and in combination against beryllium-induced biochemical alterations and oxidative stress-consequences in female albino rats. The administration of beryllium altered blood biochemical variables by significantly depleting hemoglobin, albumin and urea, whereas it enhanced bilirubin and creatinine. The release of serum transaminase, lactate dehydrogenase and ${\gamma}-glutamyl$ transpeptidase was significantly greater, and was concomitant with a decreasein serum alkaline phosphatase. A significant increase in lipid peroxidation and a decrease in glutathione, superoxide dismutase and catalase in the liver and kidney was an indication of oxidative stress due to beryllium exposure. Individual administration of gallic acid and piperine moderately reversed the altered biochemical variables, whereas the combination of these was found to completely reverse the beryllium-induced biochemical alterations and oxidative stress consequences. We concluded that gallic acid exerts a synergistic effect when administered with piperine and provides a more pronounced therapeutic potential in reducing beryllium-induced hepatorenal dysfunction and oxidative stress consequences.

Attenuation of Beryllium Induced Hepatorenal Dysfunction and Oxidative Stress in Rodents by Combined Effect of Gallic Acid and Piperine

Jun-Quan Zhao,Guo-Zhen Du,You-Cai Xiong,Yi-Fu Wen,Monika Bhadauria,Satendra Kumar Nirala 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.12

We determined a minimum effective dose of gallic acid (3,4,5-trihydroxy benzoic acid; 50 mg/ kg, i.p.) and piperine (10 mg/kg, p.o.) through their therapeutic potential and further evaluated them individually and in combination against beryllium-induced biochemical alterations and oxidative stress consequences in female albino rats. The administration of beryllium altered blood biochemical variables by significantly depleting hemoglobin, albumin and urea, whereas it enhanced bilirubin and creatinine. The release of serum transaminase, lactate dehydrogenase and γ-glutamyl transpeptidase was significantly greater, and was concomitant with a decrease in serum alkaline phosphatase. A significant increase in lipid peroxidation and a decrease in glutathione, superoxide dismutase and catalase in the liver and kidney was an indication of oxidative stress due to beryllium exposure. Individual administration of gallic acid and piperine moderately reversed the altered biochemical variables, whereas the combination of these was found to completely reverse the beryllium-induced biochemical alterations and oxidative stress consequences. We concluded that gallic acid exerts a synergistic effect when administered with piperine and provides a more pronounced therapeutic potential in reducing beryllium-induced hepatorenal dysfunction and oxidative stress consequences.

Recent Advancements in Additive Manufacturing (AM) Techniques: A Forward-Looking Review

Netrapal Singh,Hafsa Siddiqui,Bhavani Srinivas Rao Koyalada,Ajay Mandal,Viplov Chauhan,Sathish Natarajan,Satendra Kumar,Manoj Goswami,Surender Kumar 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.8

We witness noteworthy developments in multifunctional materials progress through additive manufacturing techniques,enhanced by the revolution of Industry 4.0 and Internet of Things. Still, in specific circumstances, the performance of usedmaterials is sometimes limited. Among the various existing techniques, the additive manufacturing (AM) process has gainedmuch popularity over the last two decades and is one of the most revolutionary manufacturing techniques. In this comprehensivereview, we have addressed the fundamentals of various Additive Manufacturing processes, including binder jetting,fused deposition modelling, Stereolithography, selective laser sintering/melting, direct energy deposition. Furthermore, recentadvancements and emerging new technology in AM domain named electrochemical additive manufacturing is highlightedin this review as a major part. These processes’ capabilities, advantages, limitations, and applications are also discussed. Inthe concluding sections of this work, future trends are offered and discussed.