Electrophoretic patterns of microwaved and γ‐irradiated beef liver proteins

The effects of γ‐irradiation treatments (2.5, 5 and 10 kGy) and microwaves generated from an oven at low and defrost power settings for 0.5, 1 and 2 min on the total proteins and protein patterns of beef liver immediately after treatment and during frozen storage (?18 °C) for different periods were studied. Chemical analyses indicated that the protein content of beef liver was reduced after exposure to γ‐radiation or microwaves and also during frozen storage. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE) was used to illustrate the changes in protein bands of different molecular weights and their percentages before and after exposure to gamma and microwave radiation. The main effect of γ‐radiation on the protein patterns of beef liver was the disappearance of some high‐molecular‐weight protein bands and the development of other bands characterised by moderate and low molecular weights. This finding indicates the degradation of beef liver proteins by γ‐irradiation. In contrast, microwave treatment caused an increase in the levels of high‐molecular‐weight protein bands with a concomitant decrease in low‐molecular‐weight protein bands. This phenomenon demonstrates the polymerisation of low‐molecular‐weight proteins under the influence of microwaves. © 2001 Society of Chemical Industry     

Conifer-Derived Metallic Nanoparticles: Green Synthesis and Biological Applications

The use of metallic nanoparticles in engineering and biomedicine disciplines has gained considerable attention. Scientists are exploring new synthesis protocols of these substances considering their small size and lucrative antimicrobial potential. Among the most economical techniques of synthesis of metallic nanoparticles via chemical routes, which includes the use of chemicals as metal reducing agents, is considered to generate nanoparticles possessing toxicity and biological risk. This limitation of chemically synthesized nanoparticles has engendered the exploration for the ecofriendly synthesis process. Biological or green synthesis approaches have emerged as an effective solution to address the limitations of conventionally synthesized nanoparticles. Nanoparticles synthesized via biological entities obtained from plant extracts exhibit superior effect in comparison to chemical methods. Recently, conifer extracts have been found to be effective in synthesizing metallic nanoparticles through a highly regulated process. The current review highlights the importance of conifers and its extracts in synthesis of metallic nanoparticles. It also discusses the different applications of the conifer extract mediated metallic nanoparticles.     

Review of recent advances in anaerobic packed-bed biogas reactors

Biogas digesters have captured many imaginations because they can turn organic wastes from our farms, factories and cities into a valuable source of renewable energy. In addition, the potential of this technology to reduce odors and other environmental concerns of animal feedlots has resulted in much recent interest from researchers and scientists all over the globe.Despite its numerous advantages, the potential of biogas technology could not be fully harnessed or tapped, as certain constraints are also associated with it. Researchers have tried different techniques to enhance gas production. This paper reviews the use of fixed-bed reactors in various fields reported by different researchers using variety of substrates.     

Electrochemical sensors for the determination of Zn ions based on pendant armed macrocyclic ligand

The construction and performance characteristics of polymeric membrane electrodes based on two newly synthesized macrocyclic ligands 6,7:14,15-Bzo₂-10,11-(4-methylbenzene)-[15]-6,8,12,14-tetraene-9,12-N₂-1,5-O₂ (L₁) and 6,7:14,15-Bzo₂-10,11-(4-methylbenzene)-[15]-6,14-diene-9,12-dimethylacrylate-9,12-N₂-1,5-O₂ (L₂) for the quantification of Zn²⁺ ions are described here. Several membranes having different compositions of PVC, plasticizers, ionic additives and ionophores were fabricated and the best response was observed for the membrane having composition L₂:PVC:TBP:NaTPB in the ratio of 4:37:57:2 (w/w; mg). The response characteristics of the membrane based on L₂ were compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrode exhibits Nernstian slope for Zn²⁺ ions with limits of detection of 3.3 × 10⁻⁷ mol L⁻¹ for PME and 7.9 × 10⁻⁸ mol L⁻¹ for CGE with response time of 12 s and 10 s for PME and CGE respectively. Furthermore, the electrodes generated constant potentials in the pH range of 3.0–8.0 for PME and 2.5–9.0 for CGE. The practical utility of the CGE has been demonstrated by its usage as an indicator electrode in potentiometric titration of EDTA with Zn²⁺ ion solution. The high selectivity of CGE also permits their use in the determination of Zn²⁺ ions in water, biological, milk and tea samples.     

Credibility distribution based R-norm fuzzy information measures in noiseless coding theorems

In the present communication, a parametric R-norm fuzzy entropy of a fuzzy variable and subsequently R-norm fuzzy directed divergence measure of fuzzy variables by taking the credibility distribution measure into account have been proposed along with their proof of validity. Based on the proposed information measures, some new results along with its various properties and the monotonic behavior have been studied in detail. Further, some important results and inequalities related to their corresponding noiseless coding theorems have been well established. Some particular cases related to the proposed fuzzy information measures and fuzzy mean codeword length in terms of existing results have also been discussed. In view the monotonic behavior of the fuzzy mean codeword length, an application to chose the appropriate value of the parameter R to reduce the fuzzy mean codeword length significantly for optimal code has been presented with a possible variability.     

A Comparative Study of Ratcheting Fatigue Behavior of Modified 9Cr–1Mo Steel and Inconel 617 Alloy at Homologous Temperature of 0.42

The modified 9Cr–1Mo steel and Inconel (IN) 617 superalloy are high-temperature alloys of prime importance in several industrial applications. Both of these are used at elevated temperature for various piping and tubing components and undergo asymmetric cyclic loading; therefore, it is highly essential to assess their resistance to accumulation of inelastic strain (ratcheting) under asymmetric stress cycling. In this study, ratcheting behavior of these alloys is compared at the homologous temperature of 0.42, under uniaxial asymmetric stress loading with positive mean stress. Deformation behavior of the tested samples is analyzed by transmission electron microscope. While there is homogeneous deformation in the modified 9Cr–1Mo steel, there is intersection of slip bands and presence of dislocation tangles in the IN 617 alloy. Fracture surface of the modified 9Cr–1Mo steel, tested under asymmetric cyclic loading, reveals typical ductile fracture resulting from tensile loading, whereas there is characteristic fatigue fracture of the IN 617 alloy.     

Morphological and Optical Characterization of Sol-Gel Synthesized Ni-Doped ZnO Nanoparticles

Abstract

In this work, Ni-doped ZnO nanoparticles (NPs) were successfully synthesized by sol-gel method. The as-synthesized nanoparticles were characterized to investigate their morphology, structure, purity and optical properties. XRD analysis confirmed the formation of nanoparticles with average particle size of approx. 30?nm. SEM observations show the agglomeration of nanoparticles. The purity of the as-prepared NPs was confirmed by EDX analysis. The defect states were revealed from the photoluminescence (PL) spectra. The overall results obtained indicate that Ni-doped ZnO nanoparticles are promising candidate to fabricate nanoscale optoelectronic devices due to their wide band gap and excellent UV emission properties.     

Anisotropy in impact behavior of Zr-2.5Nb pressure tube alloy

Zr-2.5Nb alloy tubes in cold worked and stress relieved (CWSR) condition serve as pressure boundary for hot coolant in Indian Pressurized Heavy Water Reactor (IPHWR). Due to both microstructural and crystallographic anisotropy, the mechanical properties in general and fracture behavior in particular are anisotropic for this material/component. In this work impact behavior of the pressure tube material was characterized over a range of temperature by impact test using specimens with crack growth direction along axial and transverse directions of the tubes. It has been found that both temperature and orientation have strong influence on the absorbed impact energy.