Sandeep Kumar

Bio: Sandeep Kumar is an academic researcher from Guru Jambheshwar University of Science and Technology. The author has contributed to research in topics: Adsorption & Electrochemical gas sensor. The author has an hindex of 36, co-authored 135 publications receiving 5350 citations. Previous affiliations of Sandeep Kumar include University of Nebraska–Lincoln & Central Scientific Instruments Organisation.

Solar energy: Potential and future prospects

Abstract: The development of novel solar power technologies is considered to be one of many key solutions toward fulfilling a worldwide increasing demand for energy. Rapid growth within the field of solar technologies is nonetheless facing various technical barriers, such as low solar cell efficiencies, low performing balance-of-systems (BOS), economic hindrances (e.g., high upfront costs and a lack of financing mechanisms), and institutional obstacles (e.g., inadequate infrastructure and a shortage of skilled manpower). The merits and demerits of solar energy technologies are both discussed in this article. A number of technical problems affecting renewable energy research are also highlighted, along with beneficial interactions between regulation policy frameworks and their future prospects. In order to help open novel routes with regard to solar energy research and practices, a future roadmap for the field of solar research is discussed.

Carbon nanotubes: a novel material for multifaceted applications in human healthcare

Abstract: Remarkable advances have been achieved in modern material technology, especially in device fabrication, and these have facilitated the use of diverse materials in various applications. Carbon nanotubes (CNTs) are being successfully implemented in drug delivery, sensing, water purification, composite materials, and bone scaffolds. Thus, CNTs must meet a wide range of criteria such as surface modification, high aspect ratio, desired conductivity, high porosity and loading, non-toxicity, specificity, and selectivity, and compatibility for device fabrication. The main focus of this review is to explore the maximum applications of CNTs for human health, and we particularly focus on nanocarrier and biomedical applications. The scope of this review initially covers the basic aspects of CNTs and is also extended further to describe their synthesis strategies as well as various challenges encountered in their functionalization, dispersion, and toxicity. Our discussion also emphasizes future directions for these emerging fields of research.

Ultracapacitors: Why, How, and Where is the Technology

Abstract: The science and technology of ultracapacitors are reviewed for a number of electrode materials, including carbon, mixed metal oxides, and conducting polymers. More work has been done using microporous carbons than with the other materials and most of the commercially available devices use carbon electrodes and an organic electrolytes. The energy density of these devices is 3¯5 Wh/kg with a power density of 300¯500 W/kg for high efficiency (90¯95%) charge/discharges. Projections of future developments using carbon indicate that energy densities of 10 Wh/kg or higher are likely with power densities of 1¯2 kW/kg. A key problem in the fabrication of these advanced devices is the bonding of the thin electrodes to a current collector such the contact resistance is less than 0.1 cm2. Special attention is given in the paper to comparing the power density characteristics of ultracapacitors and batteries. The comparisons should be made at the same charge/discharge efficiency.

High-Power Lithium Batteries from Functionalized Carbon Nanotube Electrodes

Abstract: Energy storage devices that can deliver high powers have many applications, including hybrid vehicles and renewable energy. Much research has focused on increasing the power output of lithium batteries by reducing lithium-ion diffusion distances, but outputs remain far below those of electrochemical capacitors and below the levels required for many applications. Here, we report an alternative approach based on the redox reactions of functional groups on the surfaces of carbon nanotubes. Layer-by-layer techniques are used to assemble an electrode that consists of additive-free, densely packed and functionalized multiwalled carbon nanotubes. The electrode, which is several micrometres thick, can store lithium up to a reversible gravimetric capacity of approximately 200 mA h g(-1)(electrode) while also delivering 100 kW kg(electrode)(-1) of power and providing lifetimes in excess of thousands of cycles, both of which are comparable to electrochemical capacitor electrodes. A device using the nanotube electrode as the positive electrode and lithium titanium oxide as a negative electrode had a gravimetric energy approximately 5 times higher than conventional electrochemical capacitors and power delivery approximately 10 times higher than conventional lithium-ion batteries.

Nanotechnology in Sustainable Agriculture: Recent Developments, Challenges, and Perspectives.

Abstract: Nanotechnology monitors a leading agricultural controlling process, especially by its miniature dimension. The application of nanotechnology to agriculture and food industries is resonant increased encumbrance because of the potential benefits ranging from enhanced food quality, safety to reduced agricultural inputs and enriched absorbing nanoscale nutrients from the soil. Agriculture, food and natural resources are a part of those challenges like sustainability, susceptibility, human health and healthy life. The ambition of nanomaterials in agriculture is to reduce the amount of spread chemicals, minimize nutrient losses in fertilization and increased yield through pest and nutrient management. Nanotechnology has the prospective to improve the agriculture and food industry with novel nanotools for the controlling of rapid disease diagnostic, enhancing the capacity of plants to absorb nutrients among others. The significant interest of using nanotechnology in agriculture includes specific applications like nanofertilizers and nanopesticides to trail products and nutrients levels to increase the productivity without decontamination of soils, waters and protection against several insect pest and microbial diseases. Nanotechnology may act as sensors for monitoring soil quality of agricultural field and thus it maintain the health of agricultural plants.This study provides a review of the current challenges of sustainability, food security and climate change that are exploring by the researchers in the area of nanotechnology in the improvement of agriculture.

Reviews of Modern Physics

Abstract: Associate DIETRICH BELITZ, University of Oregon Editors: Condensed Matter Physics (Theoretical) J. IGNACIO CIRAC, Max-Planck-Institut für Quantenoptik Quantum Information RAYMOND E. GOLDSTEIN, University of Cambridge Biological Physics ARTHUR F. HEBARD, University of Florida Condensed Matter Physics (Experimental) RANDALL D. KAMIEN, University of Pennsylvania Soft Condensed Matter DANIEL KLEPPNER, Massachusetts Institute of Technology Atomic, Molecular, and Optical Physics (Experimental) PAUL G. LANGACKER, Institute for Advanced Study, Princeton University Particle Physics (Theoretical) VERA LÜTH, Stanford University Particle Physics (Experimental) DAVID D. MEYERHOFER, University of Rochester Physics of Plasmas and Matter at High-Energy Density WITOLD NAZAREWICZ, University of Tennessee, Oak Ridge National Laboratory Nuclear Physics JOHN H. SCHWARZ, California Institute of Technology Mathematical Physics FRIEDRICH-KARL THIELEMANN, Universität Basel Astrophysics Senior Assistant Editor: DEBBIE BRODBAR, APS Editorial Office American Physical Society