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Zinc oxide (ZnO) electrical properties can be modified by addition of impurities or defects such as vacancies or other substances. We use sulfur (S) as a substitutional impurity and present a theoretical study on the characteristics of ZnO structures in its crystal form containing S in substitution of O. For theoretical calculations we used Density Functional Theory (DFT) with pseudopotentials and plane waves. ZnO in crystal form with S in substitution of O at heavy percentage was studied by analyzing properties like lattice characteristics, total energy, and gap energy. Lattice parameters a, b, c, and c/a ratio increase with the S-substituent percentage while the crystal stability decreases. Variation of gap energy shows a decreasing trend with increasing amount of substitution. In this paper, we provide a detailed data useful to identify the effects on ZnO in its crystal form when O is replaced by S that will help to predict if the structural changes on the modified ZnO structures may be suitable for applications in opto-electronics.

Simple theoretical method is developed to study the size dependence of equation of state of nanomaterials. The isothermal compression of Ni and ε-Fe has been computed for different particle sizes. A shift in compression curve is obtained by increasing the particle size. This demonstrates the softening of the material by increasing the particle size. For larger particle size (~100 nm) the compression curve resembles with that of the bulk. This demonstrates that the nanomaterial becomes bulk for larger particle size. The results have been compared with the available experimental data. A good agreement between theory and experiment demonstrates the validity of the method proposed in the present paper.

Biophysical economics is initiated with the long history of the relation of economics with ecological basis and biophysical perspectives of the physiocrats. It inherently has social, economic, biological, environmental, natural, physical, and scientific grounds. Biological entities in economy like the resources, consumers, populations, and parts of production systems, etc. could all be dealt by biophysical economics. Considering this wide scope, current work is a “biophysical economics at a glance” rather than a comprehensive review of the full range of topics that may just be adequately covered in a book-length work. However, the sense of its wide range of applications is aimed to be provided to the reader in this work. Here, modern approaches and biophysical growth theory are presented after the long history and an overview of the concepts in biophysical economics. Examples of the recent studies are provided at the end with discussions. This review is also related to the work by Cleveland, “Biophysical Economics: From Physiocracy to Ecological Economics and Industrial Ecology” [C. J. Cleveland, in Advances in Bioeconomics and Sustainability: Essay in Honor of Nicholas Gerogescu-Roegen, eds. J. Gowdy and K. Mayumi (Edward Elgar Publishing, Cheltenham, England, 1999), pp. 125–154.]. Relevant parts include critics and comments on the presented concepts in a parallelized fashion with the Cleveland’s work.

This research paper briefly describes the analytical and experimental utilizations of data generated from plant (wonderful kola seeds), natural resources (distilled water), organic material (iron chloride salt) and plant-mediated synthesized iron oxide nanoparticles in a bid to understudy their applications and economic relevance. The data extrapolated from the characterization phase were theoretically, chemically and statistically analyzed as a result of comparison with other data set obtained from relatively published articles or journals, which are in line with nuclear applications and energy generation. The data (generated from the experimental procedure) were converted to energy calibrated values in Mega-electron Volt (MeV).

Noise plays a major role in the behavior of various physical and biological systems, its effects being increasingly pronounced with decrease in system size. While it is jeopardizing the future development of several nanotechnologies, such as magnetic data storage, noise can also play a constructive role in many nonlinear systems, activating a resonance response. In this paper, it is proven that various hysteretic systems can exhibit such coherent behavior — a phenomenon that is generally known as coherence resonance when is solely induced by noise, and stochastic resonance when an external oscillatory signal is present. The quantity used to characterize the regularity of the stochastic output is the power spectrum, which displays a maximum at the resonance frequency. The calculation of the spectral densities for the outputs of hysteretic systems is performed in the framework of stochastic processes defined on graphs. The case of hysteretic systems described by rectangular loops is discussed and analytical expressions for the output power spectra are derived. These theoretical results suggest that hysteretic systems can be used by nanotechnology for concentrating the energy of a flat, noisy input into a short bandwidth frequency region.

In this paper, a new method for global interconnects optimization in nanoscale VLSI circuits using unequal repeater (buffer) partitioning technique is presented. The optimization is performed with the energy-delay product minimization at 65, 90, and 130 nm technology nodes and various loads, using the genetic algorithm (GA) of MATLAB. The results show more improvements of the total propagation delay with respect to the traditional equal buffer partitioning technique. This improvement is obvious for 90 and 130 nm, and with increasing capacitive load, the improvement will be achieved for 65 nm.

Regardless of the state of matter, such as solids, liquids, and gases, the smaller the matter size from bulk to nano-scale, especially in the quantum region, the more rapid is the energy increase. To this end, this study introduces the concept of a group system, in which atoms behave as one, and this system is reinterpreted as that comprising temperature–entropy (TS) energy in thermodynamic data. Based on this concept, water was passed through various mesh-like dissolved tubes, where the size and energy of the water group system were observed to change. Thereafter, as the scale and number of the meshes increased, the ozone, chlorine, and oxygen constituents, which are closely related to sterilization and washing, are generated, changing the basic water composition. Thus, this nano-size impact is not limited to solids and could facilitate in revolutionizing the future applications in fluids.

Supercapacitors and fuel cells are essential energy devices for the implementation of a real renewable energy economy. The development of highly efficient and low-cost electrode materials is one of the major challenges to improve these devices. Biomass-derived carbon materials are postulated as a very interesting alternative, as they can be obtained from inexpensive precursors and abundant resources obtained directly from nature. However, they commonly exhibit an underdeveloped porous structure and a lack of controlled surface functionalities that limit their real application. Therefore, it is essential to apply different approaches to modify and design their properties to fit the requirements of energy storage and conversion devices. This chapter attempts to provide a broad overview of the most promising strategies that can be followed to design biomass-derived carbon materials with highly efficient performance in energy applications, such as supercapacitors and fuel cells.

This paper investigates the feasibility of recycling waste heat from a diesel engine, and also the effects of using ethanol-diesel oil as an alternative fuel. Through thermodynamic analyses, the study reveals that a significant amount of energy is contained in both the exhaust gas and cooling water, and that recycling this energy will reduce emissions, conserve energy, and improve the thermal and exergy efficiency of the diesel engine. The use of ethanol-diesel oil will lead to significantly reduced exhaust emissions without significant impact on the engine's performance parameters.