Highly efficient hydrogen generation in water using 1D CdS nanorods integrated with 2D SnS₂ nanosheets under solar light irradiation

Rangappa, A. Putta,Kumar, D. Praveen,Gopannagari, Madhusudana,Reddy, D. Amaranatha,Hong, Yul,Kim, Yujin,Kim, Tae Kyu Elsevier 2020 APPLIED SURFACE SCIENCE - Vol.508 No.-

<P><B>Abstract</B></P> <P>The development of low-cost and noble-metal-free catalysts for the photoconversion of water into hydrogen (H<SUB>2</SUB>) is of great interest. Here, 2D tin(IV) sulfide (SnS<SUB>2</SUB>) ultrathin nanosheets as co‐catalysts are coupled with 1D cadmium sulfide (CdS) nanorods for the photosplitting of water into H<SUB>2</SUB>. The design of the catalyst can facilitate the passivation of the physiochemical properties of CdS and enhance H<SUB>2</SUB> evolution activity. The prepared CdS/SnS<SUB>2</SUB> composite catalyst increases the H<SUB>2</SUB> generation activity and exhibits excellent and continuous long-term photostability. The H<SUB>2</SUB> evolution rate of the optimized CdS/SnS<SUB>2</SUB> composite is approximately 9-fold that of pristine CdS nanorods. The characterization results of the CdS/SnS<SUB>2</SUB> composite reveal that the loading of SnS<SUB>2</SUB> can enhance the synergistic effects of the photocatalyst due to the effective separation, large number of exposed catalytic sites, and highly dispersed nature of the layered SnS<SUB>2</SUB>. Several characterization outcomes of CdS/SnS<SUB>2</SUB> are examined in detail (e.g., structural and surface elemental results of transmission electron microscopy, X-ray diffraction analysis, X-ray photoelectron spectroscopy). Further, the optoelectrical properties and charge-carrier excitations are investigated via ultraviolet diffuse reflectance spectroscopy, photoluminescence spectroscopy, and photoelectrochemical analysis. The proposed CdS/SnS<SUB>2</SUB> composite is a promising low-cost, noble-metal-free, and high-efficiency catalyst for the photocatalytic water-reduction reaction.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Superior hydrogen evolution rate which is nine folds higher than the CdS. </LI> <LI> Excellent separation of photo generated charge carriers on CdS/SnS<SUB>2</SUB> hybrid with SnS<SUB>2</SUB> insertion. </LI> <LI> Excellent photo stability (30 h) of the catalyst for long term practical applications. </LI> <LI> Uniform deposition of ultrathin SnS<SUB>2</SUB> sheets onto CdS by simple methods. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Optimal hydrogen evolution rate of 20.2 mmol h<SUP>−1</SUP> g<SUP>−1</SUP> facilitated by enhanced absorption and prolonged life time of charge carriers by SnS<SUB>2</SUB> as co-catalyst on CdS.</P> <P>[DISPLAY OMISSION]</P>

Screening of quinoline, 1,3-benzoxazine, and 1,3-oxazine-based small molecules against isolated methionyl-tRNA synthetase and A549 and HCT116 cancer cells including an <i>in silico</i> binding mode analysis

Bharathkumar, Hanumantharayappa,Mohan, Chakrabhavi Dhananjaya,Rangappa, Shobith,Kang, Taehee,Keerthy, H. K.,Fuchs, Julian E.,Kwon, Nam Hoon,Bender, Andreas,Kim, Sunghoon,Basappa,Rangappa, Kanchugarako The Royal Society of Chemistry 2015 Organic & Biomolecular Chemistry Vol.13 No.36

<P>Elevated activity of methionyl-tRNA synthetase (MRS) in many cancers renders it a possible drug target in this disease area, as well as in a series of parasitic diseases. In the present work, we report the synthesis and <I>in vitro</I> screening of a library of 1,3-oxazines, benzoxazines and quinoline scaffolds against human MRS. Among the compounds tested, 2-(2-butyl-4-chloro-1-(4-phenoxybenzyl)-1<I>H</I>-imidazol-5-yl)-5-(4-methoxyphenyl)-1-oxa-3-azaspiro[5.5]undecane (compound <B>21</B>) and 2-(2-butyl-4-chloro-1-(4-nitrobenzyl)-1<I>H</I>-imidazol-5-yl)-2,4-dihydro-1<I>H</I>-benzo[<I>d</I>][1,3]oxazine (compound <B>8</B>) were found to be potent inhibitors of MRS. Additionally, these compounds significantly suppressed the proliferation of A549 and HCT116 cells with IC<SUB>50</SUB> values of 28.4, 17.7, 41.9, and 19.8 μM respectively. Molecular docking studies suggested that the ligand binding orientation overlaps with the original positions of both methionine and adenosine of MRS. This suggests the binding of compound <B>21</B> against MRS, which might lead the inhibitory activity towards cancer cells.</P> <P>Graphic Abstract</P><P>Elevated activity of methionyl-tRNA synthetase (MRS) in many cancers renders it a possible drug target in this disease area, as well as in a series of parasitic diseases. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c5ob00791g'> </P>

Solidified inorganic-organic hybrid electrolyte for all solid state flexible lithium battery

Baek, Seung-Wook,Honma, Itaru,Kim, Jedeok,Rangappa, Dinesh Elsevier 2017 Journal of Power Sources Vol.343 No.-

<P><B>Abstract</B></P> <P>Solidified lithium conducting hybrid electrolyte is designed and processed to realize the large scale and flexible solid state Li battery satisfying energy capability and safety issue. This paper presents a solidified inorganic-organic hybrid electrolyte to obtain commercially-acceptable ionic conductivity and a stable electrochemical window to prevent electrolyte decomposition in Li ion batteries. Li<SUB>3</SUB>PO<SUB>4</SUB> coated with solidified [Li][EMI][TFSI] ionic liquid is developed as hybrid electrolyte material. The material has high electrochemical stability on a high-voltage cathode and metallic anode, and the solid electrolyte has high ionic conductivity. This Li<SUB>3</SUB>PO<SUB>4</SUB>-[Li][EMI][TFSI] hybrid electrolyte has the advantages of long-term operation, safety and flexibility, so it may be suitable for use in high-voltage cathodes and Li anode.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Solidified flexible hybrid electrolyte was designed and demonstrated. </LI> <LI> Hybrid electrolyte achieved an high ionic conductivity and low activation energy. </LI> <LI> Hybrid electrolyte is suitable for a flexible and safe battery with Li anode. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Microstructure, Photoluminescence and Electrical Properties of SmxGd(1−x): SrO Hybrid Nanomaterials Synthesized via Facile Coprecipitation Method

Vinayak Adimule,Basappa C. Yallur,Rangappa Keri,Chinna Bathula,Sheetal Batakurki 대한금속·재료학회 2023 ELECTRONIC MATERIALS LETTERS Vol.19 No.3

The development of triple oxide semiconductor nanostructures (NS) with special optical window is critical for the optoelectronicsand the luminescent industry. The present article describes the synthesis of Sm x :Gd (1−x) @SrO (x = 0.4, 0.6, 0.8)NS by simple Coprecipitation method. The NS were characterized by X-ray powder diff raction (XRD), scanning electronmicroscopy (SEM), SEM–EDS (energy dispersive spectra), Fourier transform infrared (FT-IR), UV–visible, X-ray photoelectronspectroscopy (XPS), and Brunauer–Emmett–Teller analytical methods. The results of the powdered XRD patternrevealed the formation of mixed-phase of hexagonal crystal structure, with grain size between 62 and 78 nm. Redshift inoptical absorption spectra for the Sm 3+ doped Gd (1−x) SrO NS appeared when compared to Gd (1−x) SrO NS. Photoluminescence(PL) spectroscopy demonstrated broad deep defect levels in Sm x : Gd (1−x) SrO NS when compared to Gd (1−x) SrONS. PL studies of Gd 0.6 , SrO exhibited three emission peaks detected at 373.6 nm, 382.1 nm, and 392.7 nm when excited at325 nm. PL studies of Sm x : Gd (1−x) SrO NS (x = 0.8) showed four emission peaks appeared at 415 nm (violet), 472 nm (blue),532.1 nm (green) and 569.6 nm (yellow) due to f–f transition of Sm 3+ in 4f 5 confi guration. Higher values of dielectric constant(3.86 × 10 4 ), dielectric permittivity (10 3 –10 5 ) resulted for the Sm x :Gd (1−x) @SrO (x = 0.8) NS with negligibly small dielectricloss (< 0.03) when compared to Gd 0.6 SrO NS. The synthesised materials demonstrated excellent luminescence propertieswith good dielectric properties therefore these materials could be good candidates to be used as high-luminescent devices.

Evaluation of Strong Microwave Absorption Property of PVB-PEDOT:PSS-Ti3C2Tx MXene Nanocomposite With Materials Data-Driven Discovery

M. Praveen Kumar,Sarika Raga,S. Chetana,K. Avinash,Arjun Dey,Dinesh Rangappa 한국전기전자재료학회 2023 Transactions on Electrical and Electronic Material Vol.24 No.3

2D nanomaterial, especially 2D metal carbides or MXene loaded polymer nanocomposite is highly valued electromagnetic material. In this work, Ti3C2TX MXene loaded polyvinyl butyral (PVB)-Poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS)-Ti3C2TX MXene nanocomposite is explored for microwave absorption in the frequency range of X-Band and Ku-Band (8.2–18 GHz). The reflection loss (RL) of the optimized PEDOT:PSS content PVB-PEDOT:PSS was found to improve significantly in presence of the Ti3C2TX MXene viz., 5%, 10%, 20% and 40%. Ti3C2TX MXene loaded solution processed PVB-PEDOT:PSS-Ti3C2TX MXene indicates RL is strongly effected by Ti3C2TX MXene loading. To optimize Ti3C2TX MXene content in PVB-PEDOT:PSS-Ti3C2TX MXene nanocomposite for best RL with minimum thickness, the materials data-driven discovery was used for which experimental data sets were used as input parameters. Through the materials data-driven discovery, the minimum RL value -63 dB was predicted at 2.6 mm for 18 wt% Ti3C2TX MXene loaded PVB-PEDOT:PSS-Ti3C2TX MXene nanocomposite which was not examine before. The predicted RL data for the optimized PVB-PEDOT:PSS-Ti3C2TX MXene nanocomposite (18 wt% MXene content) was compared with the experimental data.

X-Band Dielectric Characterization and Microwave Absorption Characteristics of Polyaniline Loaded Poly Vinyl Butyral (PVB)

M. Praveen Kumar,Sarika Raga,S. Chetana,Dinesh Rangappa 한국전기전자재료학회 2023 Transactions on Electrical and Electronic Material Vol.24 No.1

Conducting polymer-based materials received tremendous attraction in the area of microwave absorption due to their effective microwave dielectric properties. In this work, conducting polymer polyaniline (PANI) loaded polyvinyl butyral (PVB) for X-band (8.2–12.4 GHz) dielectrics and absorption characteristics are studied. Electromagnetic (EM) performances for diff erent solution processed PANI loaded (4–16 wt%) PVB-PANI are investigated and optimized the filler (PANI) loading in PVB matrix for the microwave absorption. The study reveals that the presence of PANI in PVB significantly improves the different EM properties. The minimum reflection loss (RL) value − 10 dB (corresponds to 90% absorption) is achieved for 8 wt% PANI loaded PVB (4 mm). The RL ≤ − 10 dB is achieved at minimum thickness 2–3 mm for 10–16 wt% PANI loading. The RL value − 30 dB is obtained for 2.5 mm thicker 16 wt% PANI loaded PVB with an excellent absorption bandwidth, indicating a superior result for real time application compared to other polymer nanocomposites.

Development of the body condition score system in Murrah buffaloes: validation through ultrasonic assessment of body fat reserves

Anitha Alapati,Sarjan Rao Kapa,Suresh Jeepalyam,Srinivasa Moorthy Patrapalle Rangappa,Kotilinga Reddy Yemireddy 대한수의학회 2010 Journal of Veterinary Science Vol.11 No.1

The body condition score (BCS) system is a subjective scoring method of evaluating the energy reserves of dairy animals to provide better understanding of biological relationships between body fat, milk production and reproduction. This method helps in adopting the optimum management practices to derive maximum production and maintain optimum health of the livestock. In this study, a new BCS system was developed for Murrah buffaloes. The skeletal check points were identified by studying the anatomical features and amount of fat reserves in slaughtered animals. The scores were assigned from 1 to 5based on the amount of fat reserves in slaughtered animals. A score of 1 represents least and 5 represents most amount of fat. The skeletal check points identified were ordered based on the amount of carcass fat reserves and scores assigned to prepare a preliminary BCS chart on a 1 to 5 scale at 0.25 increments. The BCS chart was further modified by eliminating the skeletal check points at which the fat reserves were less evident on palpation in most of the buffaloes and a new BCS chart on a 1 to 5 scale at 0.5 increments examining eight skeletal check points was developed. The new BCS system developed was tested for precision in 10 buffaloes for each point of the 1-5 scale by ultrasonographic measurements of body fat reserves. Ultrasonographic measurements showed that as the BCS increased, the amount of fat reserves also increased (p < 0.01), indicating that the BCS adequately reflected the amount of actual fat reserves. BCS was significantly correlated (r = 0.860) with the carcass fat reserves as well as the ultrasonographic fat reserves (r = 0.854).

Synthesis and Cytotoxic Evaluation of Novel 2-(4-(2,2,2-Trifluoroethoxy)-3-methylpyridin-2-ylthio)-1H-benzo[d]imidazole Derivatives

S. R. Ranganatha,C. V. Kavitha,K. Vinaya,D. S. Prasanna,S. Chandrappa,Sathees C. Raghavan,K. S. Rangappa 대한약학회 2009 Archives of Pharmacal Research Vol.32 No.10

The present work deals with the anticancer effect of benzimidazole derivatives associated with the pyridine framework. By varying the functional group at N-terminal of the benzimidazole by different L-amino acids, several 2-(4-(2,2,2-trifluoroethoxy)-3-methylpyridin-2-ylthio)-1Hbenzo[d]imidazole derivatives 9(a-j) were synthesized. Their chemical structures were confirmed by 1H NMR, IR and mass spectroscopic techniques. The synthesized compounds were examined for their antiproliferative effects against human leukemia cell lines, K562 and CEM. The preliminary results showed most of the derivatives had moderate antitumor activity. Compound 9j containing cysteine residue exhibited good inhibition compared to other amino acid resides. In addition DNA fragmentation results suggest that 9j is more cytotoxic and able to induce apoptosis.

Taguchi’s Optimization of Areca Fruit Husk Fiber Mechanical Properties for Polymer Composite Applications

Joseph Selvi Binoj,Natarajan Manikandan,Bright Brailson Mansingh,Vadivel Nayanar Anbazhagan,Govindarajan Bharathiraja,Suchart Siengchin,Mavinkere Rangappa Sanjay,Suyambulingam Indran 한국섬유공학회 2022 Fibers and polymers Vol.23 No.11

Owing to the exceptional characteristics such as sustainability, biodegradability and environment friendlycharacteristics natural fibers are a dominant force in a variety of composite sectors. Among the many fruit fibers, Areca fruithusk fiber (AFHF) stands out and has been discovered in considerable quantities being rejected by tobacco processingenterprises. The investigation of AFHFs, helps to utilize the wealth out of iste in an eco-friendly nature for reinforcement inpolymer composites. In light of this, the current work deals with AFHFs collected from agricultural enterprises and processedas raw fibers, which were further combined with unsaturated polyester resin to create a natural polymer composite material. Additionally, using Taguchi's design technique, an orthogonal array is constructed by including process parameters and theirstages when conducting testing. The influence of various fiber widths on various gauge distances has been discussed, as wellas the optimal width and span for defining the possible tensile strength using Taguchi's single response analysis. Additionally,the mechanical assets of manufactured natural fiber composites were evaluated using ASTM criteria to perceive whether itcan be employed as a substitute reinforcement in polymer composite products.

Cardamonin represses proliferation, invasion, and causes apoptosis through the modulation of signal transducer and activator of transcription 3 pathway in prostate cancer

Zhang, J.,Sikka, S.,Siveen, K. S.,Lee, J. H.,Um, J. Y.,Kumar, A. P.,Chinnathambi, A.,Alharbi, S. A.,Rangappa, K. S. Springer Science + Business Media 2017 Apoptosis Vol.22 No.1

<P>The pleiotropic transcription factor, signal transducer and activator of transcription 3 (STAT3) is often aberrantly activated in a wide variety of cancers and plays a pivotal role in tumor initiation, promotion and progression. Targeting deregulated STAT3 activation by small molecule inhibitors is generally considered as an important therapeutic strategy. Hence, in the present study, we evaluated the potential of cardamonin (CD), a 2',4'-dihydroxy-6'-methoxychalcone, to modulate STAT3 activation in prostate cancer (PC) cells and found that this chalcone can indeed exhibit significant anticancer effects through negatively regulating STAT3 activation by diverse molecular mechanism(s). CD suppressed STAT3 phosphorylation, nuclear translocation and DNA binding ability in PC cells. Computational modeling revealed that CD can bind directly to the Src Homology 2 domain of STAT3 and also effectively inhibit its dimerization. CD was also found to significantly reduce the migratory/invasive potential of PC cells through the downregulation of various oncogenic proteins. Overall, the data indicates that the potential application of CD as a STAT3 blocker can mitigate both the growth and survival of PC cells.</P>