Storage and permeation of hydrogen molecule,atom and ions (H+ and H−) through silicon carbide nanotube; a DFT approach

The barriers for the encapsulation and decapsulation of hydrogen ions (cationic hydrogen and hydride), atom, and molecule through silicon carbide nanotube are thoroughly studied. DFT method is selected to measure the kinetic barriers for the passage of hydrogen atom, ions and molecule through nanotube via scanning potential energy surface. The kinetic barriers for the passage (encapsulation and decapsulation) of hydrogen are very important to understand the mechanism of hydrogen storage and release. The barriers for the permeation of H, H⁺ and H^? across SiC nanosheet are lower compared to hydrogen molecule (H₂). The exohedral and endohedral adsorption of hydrogen ions (cation and anion), atom and exohedral hydrogen molecule on silicon carbide are exothermic in nature. Whereas the encapsulation of hydrogen molecule in silicon carbide is endothermic. Electronic properties are analyzed through measurement of energy gap between highest occupied and lowest unoccupied molecular orbitals gap (G_H-L) and the density of state (DOS) spectra. The G_H-L analysis reveals that endohedral complexes have more pronounced effect on electronic properties compared to exohedral complexes. The SiC nanotube has highly favorable properties for storage and release of hydrogen ions, and atom.     

Terpenoids as Human Neutrophil Elastase (HNE) Inhibitors: A Comprehensive Review of Natural Anti-inflammatory Isoprenoids

Human neutrophil elastase (HNE) is an enzyme that plays a key role in the body‘s inflammatory response. It has been linked to several diseases such as chronic obstructive pulmonary disease (COPD), emphysema, and cystic fibrosis. As potential treatments for these diseases, HNE inhibitors are of great interest. Metabolites derived from plants, particularly terpenoids such as β-caryophyllene found in black pepper and other plants, and geraniol present in several essential oils, are recognized as significant sources of inhibitors for HNE. Because of their ability to inhibit HNE, terpenoids are considered promising candidates for developing novel therapies to treat inflammatory conditions such as COPD and emphysema. Furthermore, nature can serve as an excellent designer, and it may offer a safer drug candidate for inhibiting HNE production and activity in the future. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were searched to get relevant and up-to-date literature on terpenoids as human neutrophil elastase inhibitors. This review focuses on the isolation, chemical diversity, and inhibition of human neutrophil elastase (HNE) of various terpenoids reported from natural sources up to 2022. A total of 251 compounds from various terpenoids classes have been reported. Further, it also provides a summary of HNE inhibitors and includes a thorough discussion on the structure-activity relationship.     

Designing Pair of Nonlinear Components of a Block Cipher over Gaussian Integers

In block ciphers, the nonlinear components, also known as substitution boxes (S-boxes), are used with the purpose of inducing confusion in cryptosystems. For the last decade, most of the work on designing S-boxes over the points of elliptic curves has been published. The main purpose of these studies is to hide data and improve the security levels of crypto algorithms. In this work, we design pair of nonlinear components of a block cipher over the residue class of Gaussian integers (GI). The fascinating features of this structure provide S-boxes pair at a time by fixing three parameters. But the prime field dependent on the Elliptic curve (EC) provides one S-box at a time by fixing three parameters and . The newly designed pair of S-boxes are assessed by various tests like nonlinearity, bit independence criterion, strict avalanche criterion, linear approximation probability, and differential approximation probability.     

Searching surface orientation of microscopic objects for accurate 3D shape recovery

In this article, we propose a new shape from focus (SFF) method to estimate 3D shape of microscopic objects using surface orientation cue of each object patch. Most of the SFF algorithms compute the focus value of a pixel from the information of neighboring pixels lying on the same image frame based on an assumption that the small object patch corresponding to the small neighborhood of a pixel is a plane parallel to the focal plane. However, this assumption fails in the optics with limited depth of field where the neighboring pixels of an image have different degree of focus. To overcome this problem, we try to search the surface orientation of the small object patch corresponding to each pixel in the image sequence. Searching of the surface orientation is done indirectly by principal component analysis. Then, the focus value of each pixel is computed from the neighboring pixels lying on the surface perpendicular to the corresponding surface orientation. Experimental results on synthetic and real microscopic objects show that the proposed method produces more accurate 3D shape in comparison to the existing techniques.     

Comparison of Methods for Colorimetric Amylose Determination in Cereal Grains

Iodine‐based colorimetry remains the most widespread method for the determination of amylose content of starch. There are, however, many variants of this method, differing in solvent, temperature and method for converting absorbance to amylose content. Therefore, in thisstudy some of these methods were compared in order to identify which, if any, was most reliable. Australian commercial samples of wheat, rice, rye and oat were used. Flour was ground and starch was extracted. Half of the samples of flour and starch were defatted with n‐propanol. Defatted and full‐fat flours and starches were dissolved by six procedures: DMSO, urea‐DMSO, CaCl₂‐DMSO, hot NaOH, cold NaOH and HCl. The solutions were diluted, coloured with iodine and the absorbances determined at 535 and 620 nm. Amylose content was determined by reference to standards using 620 nm as the single wavelength or by two calculations based on the ratio between the two absorbances. Reliability was tested by repeating all tests on three non‐consecutive days with three replicates on each day. Defatted starch provided more consistent results than flour or non‐defatted starch. The most reliable dissolution procedure, with both the lowest standard error and least day‐to‐day variation, was cold NaOH. One of the ratio‐based calculations provided adequate correction for the non‐starch content of flour of wheat and rice, but not of the other two cereals, and the other ratio‐based calculation seldom provided realistic results. It is concluded that a cold NaOH dissolution procedure is suitable for reliable amylose determination on defatted starch of a range of cereals from a single wavelength and that it is also suitable for use on defatted flour of some species.     

Managing Information for Effective Business Partner Relationships

Partner Relationship Management (PRM) is an information strategy that employs a set of applications focused on directly impacting an enterprise and its business partners' sales and services. Web services employ a distributed computing architecture that consists of many different computers that communicate over the Internet to form one system. the communication standards and protocols used in Web services are universally accepted. These Web services can be requested by client applications: Web based, windows, or mobile devices. This article presents an overview of PRM and Web services, and discusses the potential for improving partner relationship processes through the use of Web services.     

A novel discrete image encryption algorithm based on finite algebraic structures

Multimedia Tools and Applications - The arithmetic properties of a finite field have a remarkable impact on the security features of symmetric and asymmetric cryptosystems. Conventionally, in...     

Thermodynamic screening of suitable oxygen carriers for a three reactor chemical looping reforming system

Hydrogen (H₂) production by using a three reactor chemical looping reforming (TRCLR) technology is an innovative process which utilizes fossil fuels as feed stocks. This process occurs in three steps by employing an oxygen carrier (OC), which is generally a transition metal. As the OC plays an important role, its selection should be done after carefully considering the chemical and physical properties of the material. In this study, various candidate materials for use in a TRCLR process, with methane (CH₄) as a fuel stock, were investigated. The results show that the iron (Fe)- and molybdenum (Mo)-based OCs oxidize CH₄ completely in the FR at low temperatures. In terms of H₂ yield, tungsten (W)-based OCs produce the highest yield, ～3.9 mol-H₂/mol-CH₄. The equilibrium oxygen partial pressures and the solid circulation rates are the highest for Fe-based OCs. The oxygen carrying capacity of Fe-based OCs is relatively high while its price is low. Therefore, among the OCs investigated, Fe-based OCs were identified as the preferred OC option for a TRCLR process.