High yield synthesis of electrolyte heating assisted electrochemically exfoliated graphene for electromagnetic interference shielding applications

Herein, we demonstrate a facile one pot synthesis of graphene nanosheets by electrochemical exfoliation of graphite. In the present study, we report a significant increase in the yield of graphene by electrolyte heating assisted electrochemical exfoliation method. The obtained results of heating assisted electrochemically exfoliated graphene (utilizing H2SO4 + KOH + DW) synthesis clearly exhibit that the yield increases similar to 4.5 times i.e. from similar to 17% (room temperature) to similar to 77% (at 80 degrees C). A plausible mechanism for the enhanced yield based on lattice expansion and vibration of intercalated ions has been put forward and discussed in details. The quality of graphene was examined by Raman, XPS, FTIR, AFM, SEM, TEM/HRTEM and TGA techniques. The Raman as well as morphogenesis results confirm the quality of the graphene nanosheets. We have used this graphene as electromagnetic interference shielding material where a comparatively large quantity of graphene is required. This graphene exhibits enhanced shielding effectiveness (46 dB at 1 mm thickness of stacked graphene sheets in frequency region 12.4 to 18 GHz) as compared to conventional electromagnetic interference shielding materials, which is greater than the recommended limit (similar to 30 dB) for techno-commercial applications. Thus the present work is suggestive for future studies on enhancement of yield of high quality graphene by proposed method and the use of synthesized graphene in electromagnetic interference shielding and other possible applications

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

A highly porous, light weight 3D sponge like graphene aerogel for electromagnetic interference shielding applications

Here we report the microwave shielding properties of a light weight three dimensional (3D) sponge like graphene aerogel (GA) derived from graphene oxide (GO). GA is a new exotic form of graphene nanosheet, which shows improved shielding features as compared to its pristine counterpart. The structural and microstructural characteristics of this new indigenous 3D sponge like graphene aerogel architecture have been probed by XRD, Raman, SEMand TEM/HRTEM. Furthermore, the porosity of this newly synthesized structure has been investigated by the Brunauer-Emmett-Teller (BET) method, which confirms the high surface area of similar to 516 m(2) g(-1) with an average pore diameter of similar to 2.5 nm. The high surface area and better porosity improve the EMI shielding effectiveness of GA. Simultaneously, the GA nanostructure also enhances the dielectric properties which provide a better alternative for EMI shielding materials as compared to GO. This engineered GA exhibits enhanced shielding effectiveness (similar to 20.0 dB at 0.20 g in a frequency region of 12.4 to 18.0 GHz) as compared to the conventional GO. Thus, the result of the EMI shielding of GA offers a new ingenious nanostructure which can be used as an EMI pollutant quencher for next-generation EMI shielding devices

New emerging radially aligned carbon nano tubes comprised carbon hollow cylinder as an excellent absorber for electromagnetic environmental pollution

Herein, we demonstrated the synthesis of a hollow cylinder with a new architecture of up to several centimeters in diameter and several centimeters long and having similar to 100 mm wall thickness. The hollow carbon cylinder was formed by radially aligned CNTs. These CNTs were grown on ferrocene derived Fe nanoparticles deposited throughout the inner wall of the quartz growth tube. This new ingenious carbon architecture was grown by a customized spray pyrolysis method. Furthermore, we also synthesized such carbon hollow cylinders using different precursor concentrations (ferrocene: benzene), different phases and microstructures to evaluate their EMI shielding effectiveness. The structural and microstructural characterizations of these hollow carbon cylinders comprising radially aligned CNTs were examined through various techniques, including XRD, Raman, FTIR, XPS, SEM, TEM, and HRTEM spectroscopy. Furthermore, the magnetic measurements (M-H) were performed for such structures to probe the magnetic properties of these carbon hollow cylinders for different concentrations. Furthermore, the EMI shielding through different concentrations of Fe bearing CNTs were explored in detail for tailoring the desired shielding effectiveness value for possible potential applications. Hence, our synthesis method provides a unique architecture for promising next generation building blocks in the form of carbon hollow cylinders made up of radially aligned CNTs over the conventional randomly oriented CNTs. This could be directly used to make it as a co-axial cover for electrical cables to protect them from EMI pollutants

SAtellite-based Marine Process Understanding, Development, Research and Applications for Blue Economy (SAMUDRA): A Technology Demonstration Program in the Bay of Bengal

SAtellite-based Marine Process Understanding, Development, Research and Applications (SAMUDRA) for blue economy, a technology development program of the Space Applications Centre, is an umbrella program covering research and applications geared toward physical and biological oceanography making use of current and future satellite observations for developing the nation’s blue economy. The main motivation behind this project was to develop satellite and numerical model-based information and value-added products and to demonstrate the implementation of developed applications for operational requirements. The program also aimed at improving existing methodologies for various applications by utilizing space-based inputs. Several field campaigns with the use of NavIC-enabled instruments and NABHMITRA were conducted for measuring biophysical parameters and validation of developed applications in the coastal regions. One of the key aspects of this project was development of web-based customized tools/dissemination system for providing the information to the end users. Some of the key/notable achievements of SAMUDRA were development of a portal OceanEye (tailor-made web-portal for Shipping Corporation of India), storm-surge/inundation system, oil-spill trajectory modeling, level-next potential fishing zone algorithm and rip current alert system

Abstracts of National Conference on Biological, Biochemical, Biomedical, Bioenergy, and Environmental Biotechnology

This book contains the abstracts of the papers presented at the National Conference on Biological, Biochemical, Biomedical, Bioenergy, and Environmental Biotechnology (NCB4EBT-2021) Organized by the Department of Biotechnology, National Institute of Technology Warangal, India held on 29–30 January 2021. This conference is the first of its kind organized by NIT-W which covered an array of interesting topics in biotechnology. This makes it a bit special as it brings together researchers from different disciplines of biotechnology, which in turn will also open new research and cooperation fields for them. Conference Title: National Conference on Biological, Biochemical, Biomedical, Bioenergy, and Environmental BiotechnologyConference Acronym: NCB4EBT-2021Conference Date: 29–30 January 2021Conference Location: Online (Virtual Mode)Conference Organizer: Department of Biotechnology, National Institute of Technology Warangal, Indi

Abstracts of National Conference on Research and Developments in Material Processing, Modelling and Characterization 2020

This book presents the abstracts of the papers presented to the Online National Conference on Research and Developments in Material Processing, Modelling and Characterization 2020 (RDMPMC-2020) held on 26th and 27th August 2020 organized by the Department of Metallurgical and Materials Science in Association with the Department of Production and Industrial Engineering, National Institute of Technology Jamshedpur, Jharkhand, India. Conference Title: National Conference on Research and Developments in Material Processing, Modelling and Characterization 2020Conference Acronym: RDMPMC-2020Conference Date: 26–27 August 2020Conference Location: Online (Virtual Mode)Conference Organizer: Department of Metallurgical and Materials Engineering, National Institute of Technology JamshedpurCo-organizer: Department of Production and Industrial Engineering, National Institute of Technology Jamshedpur, Jharkhand, IndiaConference Sponsor: TEQIP-