Enhancing performance properties of conventional leather finishing topcoat by incorporating metal oxide based formulations

Content: ZnO nanoparticles were developed by 1:2 ratios of Zinc sulphate heptahydrate and Sodium hydroxide by using precipitation method. The structure, morphology of ZnO nanoparticles were investigated by using XRay Diffraction, Scanning Electron Microscopy and Transmission electron Microscopy. X-Ray Diffraction confirms the formation and average crystallite size of ZnO nanoparticles. Scanning Electron Microscopy studies shows the ZnO nanoparticles were in spherical in structure. These ZnO nanoparticles were used in different ratios along with conventional finishing formulations and coated on the leather surface. The performance properties such as water fastness, rub fastness and flexing resistance were evaluated. Application of ZnO nanoparticles in leather finishing showed significant improvement in overall performance properties than conventional finishing formulations. XRD confirms the formation of ZnO nanoparticles (wurtzite structure) at 36.67° (101) plane and the particles size was in the range of 43 nm. SEM image shows that the particles are in the spherical structure wheras EDAX investigate the stoichiometry and chemical purity of the samples to confirm the presence of zinc and oxygen. Optimum quantity up to 2-5 g/L of the season of ZnO nanoparticle is desirable for upgrading the value of leathers by improving color fastness to water, rub fastness and flexing resistance (wet & dry) properties significantly in cationic (wet), NC lacquer emulsions and PU top coat dispersions in finishing formulations. Take-Away: Optimum quantity up to 2-5 g/L of the season of ZnO nanoparticle is desirable for upgrading the value of leathers by improving color fastness to water, rub fastness and flexing resistance (wet & dry) properties significantly in cationic (wet), NC lacquer emulsions and PU top coat dispersions in finishing formulations

Sophisticated Cloning, Fermentation, and Purification Technologies for an Enhanced Therapeutic Protein Production: A Review

The protein productions strategies are crucial towards the development of application based research and elucidating the novel purification strategies for industrial production. Currently, there are few innovative avenues are studies for cloning, upstream, and purification through efficient bioprocess development. Such strategies are beneficial for industries as well as proven to be vital for effectual therapeutic protein development. Though, these techniques are well documented, but, there is scope of addition to current knowledge with novel and new approaches and it will pave new avenues in production of recombinant microbial and non-microbial proteins including secondary metabolites. In this review, we have focussed on the recent development in clone selection, various modern fermentation and purification technologies and future directions in these emerging areas. Moreover, we have also highlighted notable perspectives and challenges involved in the bioengineering of such proteins, including quality by design, gene editing and pioneering ideas. The biopharmaceutical industries continue to shift towards more flexible, automated platforms and economical product development, which in turn can help in developing the cost effective processes and affordable drug development for a large community

Sustainable value creation from leather solid wastes: Preparation of shoe soling material using nano fillers

Content: Leather manufacturing involves discharge of large quantities of solid and liquid wastes. While efficient recycling methods and in-plant controls have considerably reduced the discharge of obnoxious liquid streams, satisfactory methods to the solid waste management still elude the leather manufacturers. Landfilling is an easy option for the disposal of solid wastes like chrome shavings and trimmings, but is subjected to stringent environmental regulations because of the presence of chromium in these materials. Considerable efforts have been made to recycle the chrome containing wastes by methods such as incineration, pyrolysis and alkaline or enzyme hydrolysis. These recycling processes, however, are seldom complete without further environmental problems. Unfortunately, in such recycling processes the inherent fibrous structure of these materials gets completely destroyed. Applications based on the fibrous nature of the shavings and trimmings are presently limited but various possibilities are being explored continuously. An efficient way of utilization of these fibrous waste materials may be to combine them in a suitable form with synthetic polymers to give composite materials. Short fiber reinforcement of polymers is an important area in polymer composites where both synthetic and natural fibers are effectively used. Footwear has become a basic necessity like food, shelter and clothes. Soles are bottom components of footwear and some important polymeric materials used in footwear fabrication are last, soles and Insoles. This research aims at reducing the solid waste (Chrome shavings) generated by leather industry and reusing them as low cost shoe components such as soles and insole material. In this research, the footwear components were prepared using chrome shaving (tannery solid waste), EPDM (ethylene propylene monomer rubber) and isoprene rubber with different inorganic oxide/hydroxide nano particle based fillers. In this study, soles are prepared by using strap cutting machine, two roll mill and compression moulding machine. The soling materials made characterised using FT-IR and SEM and tested for mechanical properties. Due to good mutual compatibility between Isoprene, EPDM and leather fibre with inorganic nano clay based fillers, the composites are well in terms of all the physic-mechanical behaviours like hardness, density, abrasion resistance and grain crack suitable for shoe sole application. Take-Away: 1. Ethylene propylene monomer rubber and leather fibre with inorganic nano clay based fillers, the composites are well in terms of all the physic-mechanical behaviours like hardness, density, abrasion resistance and grain crack suitable for shoe sole application. 2. An efficient way of utilization of these fibrous waste materials may be to combine them in a suitable form with synthetic polymers to give composite materials. Short fiber reinforcement of polymers is an important area in polymer composites where both synthetic and natural fibers are effectively used

Step energy and step interactions on the reconstructed GaAs(001) surface

Using ab initio total energy calculations we have studied the relation between the step atomic configuration and its properties (step energy, donor/acceptor behavior, and step interaction) on a beta(2)(2 x 4) reconstructed GaAs (001) surface. The results have been tested against the widely used elastic dipole model for the step energy and step interaction considered valid for stress-free surfaces. We have found that acceptor-behaving steps have an attractive interaction and donor-behaving steps have a repulsive interaction in contrast with the elastic dipole model which predicts always a repulsive interaction between like-oriented steps. To account for the attractive interaction we consider the electrostatic dipole interaction having the L-2 scaling with the step distance L and therefore compatible with the standard elastic model. Using a model charge distribution with localized point charges at the step based on the electron counting model we show that the electrostatic step interaction can indeed be generally attractive and of the same order of magnitude of the negative elastic dipole interaction. Our results show however that the usually employed dipole model is unable to account for the repulsive/attractive step interaction between donorlike/acceptorlike steps. Therefore, the ab initio results suggest an important electronic contribution to the step interaction, at least at the short step distances accessible to the first-principles study. Our results explain qualitatively many experimental observations and provide an explanation to the step bunching phenomenon on GaAs(001) induced by doping or by critical growth conditions as due to the stabilization of attractively interacting step structures. These ideas would lead to the development of a bottom-up surface step engineering

Anatomical Variations of Cystic Ducts in Magnetic Resonance Cholangiopancreatography and Clinical Implications

Background. Anatomical variations of cystic duct (CD) are frequently unrecognized. It is important to be aware of these variations prior to any surgical, percutaneous, or endoscopic intervention procedures. Objectives. The purpose of our study was to demonstrate the imaging features of CD and its variants using magnetic resonance cholangiopancreatography (MRCP) and document their prevalence in our population. Materials and Methods. This study included 198 patients who underwent MRCP due to different indications. Images were evaluated in picture archiving communication system (PACS) and variations of CD were documented. Results. Normal lateral insertion of CD at middle third of common hepatic duct was seen in 51% of cases. Medial insertion was seen in 16% of cases, of which 4% were low medial insertions. Low insertion of CD was noted in 9% of cases. Parallel course of CD was present in 7.5% of cases. High insertion was noted in 6% and short CD in 1% of cases. In 1 case, CD was draining into right hepatic duct. Congenital cystic dilation of CD was noted in one case with evidence of type IV choledochal cyst. Conclusion. Cystic duct variations are common and MRCP is an optimal imaging modality for demonstration of cystic duct anatomy