Activity Guided Isolation of Antioxidant Tannoid Principles from Anogeissus latifolia

Raghavan Govindarajan1*,Madhavan Vijayakumar1,,Annie Shirwaikar2,,Ajay Kumar Singh Rawat1,,Shanta Mehrotra1,,Palpu Pushpangadan1 한국생약학회 2005 Natural Product Sciences Vol.11 No.3

Oxidative stress is an important causative factor in several human chronic diseases, such asatherosclerosis, cardiovascular disorders, mutagenesis, cancer, several neurodegenerative disorders, and the agingprocess. Phenolics and tannins are reported to be good antioxidants. Anogeissus latifolia (Combretaceae) bark hasnot available till date. Hence the present study was undertaken to isolate antioxidant compounds by activity-guided isolation. Inhibtion of diphenyl picryl hydrazyl (DPH) and Xanthine oxidase along with photoc-hemiluminescence assay were used as bioassay for antioxidant activity. Activity guided isolation was carried outusing silica column and the compounds were quantified using HPLC. Ethyl acetate and butanol fraction exhibitedpotent antioxidant activity. Bioassay-guided isolation led to isolation of ellagic acid (1) and dimethyl ellagic acid(2these three major tannoid principles present in A. latifolia, are responsible for the antioxidant potential andpossibly their therapeutic potential.

Emission characteristics of the shower particles produced in the interaction of 84Kr with emulsion 1 Gev per nucleon

Rawat U.,Singh M. K.,Goyal M. 한국물리학회 2023 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.83 No.6

In the interactions of 84Kr with emulsion at 1 A GeV, the forward and backward emission of relativistic and fast hadrons was experimentally investigated. We focused on how the target fragment infuences the average multiplicities of shower particles discharged in both the forward and backward hemispheres, as well as on one another, in the current research. We have also investigated how the correlation strength varies with projectile mass. The research backs up the fnding that the creation of particles in the backward hemisphere is caused by a collective mechanism and is found to be compatible. The results are contrasted with the measurements from other tests and found to be consistent.

Two dimensional size-mass distribution function inversion from differential mobility analyzer-aerosol particle mass analyzer (DMA-APM) measurements

Rawat, V.K.,Buckley, D.T.,Kimoto, S.,Lee, M.H.,Fukushima, N.,Hogan, C.J. Pergamon Press ; Elsevier Science Ltd 2016 Journal of aerosol science Vol.92 No.-

<P>We developed and applied a data inversion routine to determine the number based size-mass distribution function (the two dimensional distribution function) from tandem differential mobility analyzer-aerosol particle mass analyzer (DMA-APM) measurements. The two dimensional distribution function is expressed in units of particle number concentration per unit mobility diameter per unit particle mass. It can be used to directly calculate the number based size distribution (commonly determined using DMA measurements) or the mass based size distribution (commonly inferred from impactor measurements). The inversion routine utilizes the Twomey-Markowski algorithm and is applied in this study to DMA-APM measurements of sodium chloride, cesium iodide, and ammonium sulfate particles in the 30-200 nm mobility diameter range, as well as acetylene flame generated soot aggregates in the 40-350 nm range. To utilize the inversion routine, the APM transfer function must be known a priori. Here it is computed using a modified version of the Ehara (uniform flow) model, with a transmission correction factor inferred from measurements. For the three examined salt particle types, visual representation of the two dimensional distribution function reveals that at a given mobility diameter, particles have very narrow mass distributions, with the peak masses in good agreement with predictions based on bulk salt densities. However, for soot particles, extremely broad distributions are observed. Soot measurements are compared to predictions for quasifractal aggregates in the transition regime; this comparison suggests that aggregates with fractal dimensions ranging from 1.4 to 2.5 are all generated in the same system. Finally, we determine the two-dimensional distribution function for a mixture of ammonium sulfate and soot particles, demonstrating that these two particle populations are separable from one another via mobility-mass analysis. (C) 2015 Elsevier Ltd. All rights reserved.</P>

Low Thermal Conductivity and High Thermoelectric Performance in In4Se3−x with Phase-Separated Indium Inclusions

Rawat, P. K.,Park, H.,Hwang, J.,Kim, W. Springer Science + Business Media 2017 Journal of electronic materials Vol.46 No.3

<P>We report the thermoelectric properties of undoped hot-pressed In4Se3-x (x = 0.05). Stoichiometric imbalance due to selenium deficiency in In4Se3 was found to create a secondary phase of elemental indium in the host material. Heat treatment drove grain growth and increased the indium solubility in In4Se3. Indium-rich domains at grain surfaces/boundaries in untreated samples were found to redistribute inside the grains and their junctions after heat treatment. Due to enhanced phonon scattering by secondary phase of indium, very low values of thermal conductivity were observed for all samples, leading to a maximum thermoelectric figure of merit (zT) of 1.13 at 723 K along the hot-pressing direction for the heat-treated sample.</P>

Low-Temperature Photochemically Activated Amorphous Indium-Gallium-Zinc Oxide for Highly Stable Room-Temperature Gas Sensors

Jaisutti, Rawat,Kim, Jaeyoung,Park, Sung Kyu,Kim, Yong-Hoon American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.31

<P>We report on highly stable amorphous indium-gallium-zinc oxide (IGZO) gas sensors for ultraviolet (UV)-activated room-temperature detection of volatile organic compounds (VOCs). The IGZO sensors fabricated by a low-temperature photochemical activation process and exhibiting two orders higher photocurrent compared to conventional zinc oxide sensors, allowed high gas sensitivity against various VOCs even at room temperature. From a systematic analysis, it was found that by increasing the UV intensity, the gas sensitivity, response time, and recovery behavior of an IGZO sensor were strongly enhanced. In particular, under an UV intensity of 30 mW cm(-2), the IGZO sensor exhibited gas sensitivity, response time and recovery time of 37%, 37 and 53 s, respectively, against 750 ppm concentration of acetone gas. Moreover, the IGZO gas sensor had an excellent long-term stability showing around 6% variation in gas sensitivity over 70 days. These results strongly support a conclusion that a low-temperature solution-processed amorphous IGZO film can serve as a good candidate for room-temperature VOCs sensors for emerging wearable electronics.</P>

Characterization of household solid waste and current status of municipal waste management in Rishikesh, Uttarakhand

Suman Rawat,Achlesh Daverey 대한환경공학회 2018 Environmental Engineering Research Vol.23 No.3

The municipal solid waste (MSW) management system in one of the Class II Indian cities i.e. Rishikesh was studied and analysed to identify the key issues in solid waste management in the city. A total of 329 solid waste samples from 47 households were collected to characterize the household solid waste (HSW). The average (HSW) generation rate was 0.26 kg/c/d and it was composed of organic waste (57.3%), plastics (14%), paper (10.9%), and glass and ceramic (1.3%) and other materials (16.5%). There was an inverse relationship between household waste generation rate and family size (p < 0.05). The MSW management system practiced in Rishikesh is unsound. There is no waste segregation at source, no provisions of composting and no recycling by formal sector. The collection and transportation of waste is inadequate and inappropriate. Collected waste is dumped in open dumping site without scientific management. Following are some recommendations for developing a sustainable solid waste management system in Rishikesh city: (1) sensitize people for segregation at source; (2) promote reduction, reuse and recycling of wastes; (3) promote community based composting; (4) provision for 100% door to door collection and; (5) formalize the informal sectors such as rag pickers and recycling industries.

Free Vibration Analysis of Thin Circular Cylindrical Shell with Closure Using Finite Element Method

Aruna Rawat,Vasant A. Matsagar,A.K. Nagpal 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.1

Vibration analysis of a thin circular cylindrical shell with closure is conducted using fi nite element method (FEM). Theoretically, shell vibrates in diff erent axial modes, m ; circumferential modes, n ; and any of their combinations with corresponding modal frequencies. The present FEM results are verifi ed by the results reported in the literature using various shell theories. The eigenvalues of the shell are extracted using block Lanczos and subspace iteration methods, in order to investigate their computational effi cacy. Further, the eff ect of adding various types of closures at one end of the circular cylindrical shell such as fl at, cone, and dome, on the modal frequencies are investigated. The two aspect ratios (length to radius ratio) of shell with closure, broad, and slender are considered for this study. The eff ect of the ratio of the thickness of the closure to the thickness of shell wall on the frequency is also investigated. For the shell with the closure, the vibration modes can be cylinder, closure, or combined cylinder and closure. The modal frequency of the cylindrical shell is signifi cantly aff ected by the closure. The lowest frequency is observed in the fl at type of closure in both the broad and slender cylindrical shells in comparison to the non-closure, dome, and cone type of the closures.

Review on Rhododendron arboreum - a magical tree

Pramod Rawat,Nishant Rai,Naveen Kumar,R. K. Bachheti 경희대학교 융합한의과학연구소 2017 Oriental Pharmacy and Experimental Medicine Vol.17 No.4

Rhododendron arboreum is medicinally and economically a very important plant species. It is widely popular for the processed juice of its flowers which have gained market popularity as rhodojuice / sharbat. Various parts of the plant exhibited medicinal properties and are used for the treatment of various ailments. Detail search has been performed from various internal databases such as Scopus, Science Direct and Google Scholar etc. to get complete work done on Rhododendron arboreum. The present review is about collection of all the available data of Rhododendron arboreum on pharmacognosy, phytochemistry, pharmacological uses. This review high lists some of the new research which explains the multifaceted activity of Rhododendron arboreum.

Anomaly Recognition in Online Social Networks

Ashish Rawat,Gunjan Gugnani,Minakshi Shastri,Pardeep Kumar 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.7

The popularity of social networking sites has increased throughout the decade and everything that gains immense popularity with great human involvement also brings many challenges and issues along with it. Similarly the excessive use of online social networking causes a great increase in anomalies. In social networking the anomalies are like fake account, account hack, identity theft, spams and many other illegitimate activities. It is thus necessary to detect such anomalous and suspicious behavior of any user at these social platforms, as they could have an adverse impact on users, especially on teenagers. In this paper, we propose various methodologies for early detection of suspicious and anomalous activities. We have done the analysis of various parameters of social networking and its graph like indegree, outdegree, active time of a node (user) and its behavior.

Formation of Iron-oxide Nanorods on the Surface of Silicon by Using Annealing Technique

Nitin Rawat,Sarita Kumari,Rajesh Kumar 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.12

In this article, we report the synthesis of iron-oxide nanorods on silicon (Si) substrates. The nanorods were formed by annealing an iron chloride solution on the surface of a Si at 950 C in the presence of a reducing gas (H2) and a diluting gas (Ar). The surface morphologies of the nanorods were investigated by using field-emission scanning electron microscopy, and their compositions and structural characterization were investigated by elemental using energy dispersive X-ray spectroscopy and high-resolution transmission electron microscopy (HRTEM), respectively. The HRTEM study shows a crystalline formation of the nanorods. The electron diffraction pattern along the viewing (111) direction and the HRTEM result shows an interplanar distance equal to 2.17 °A, which is nearly equal to the standard value 2.3 °A of FeO. The as-fabricated nanorods can be used for many technological applications.