Comparison of Surface Coatings by Plasma Spray Technique and Biomimetic Deposition on Ti Alloy Substrate: Morphology,Composition, and Corrosion Resistance Property

Protection of Metals and Physical Chemistry of Surfaces - In this study, hydroxyapatite (HAP) coatings were deposited on Ti alloy substrate by biomimetic method deposition and plasma spray...     

Enzymolysis and glycosylation synergistic modified ovalbumin: functional and structural characteristics

The functional and structural properties of enzymatic hydrolysis and glycosylation synergistic modified ovalbumin (OVA) were investigated. The results showed that hydrolysis and glycosylation had synergetic effects on emulsifying and foaming properties, water and oil-binding capacity of OVA. And hydrolysis and glycosylation also could improve gel strength and thermal properties of OVA. Polyacrylamide gel electrophoresis analysis implied that the formation of 20.1 kDa ~ 29 kDa Maillard reaction products (MRPs). UV absorption and Fourier Transform Infrared spectroscopy analyses confirmed that enzymatic hydrolysis and glycosylation could change the secondary structure of OVA. Moreover, hydrolysis and glycosylation could produce OVA with compact and orderly network structure.     

Development of a low-cost oxy-hydrogen bio-fuel cell for generation of electricity using Nostoc as a source of hydrogen

An oxy-hydrogen bio-fuel cell, based on a carbon–carbon electrode has been fabricated. The electrode pellets were prepared by taking carbon powder mixed with polyvinylalcohol as a binder. The anode was charged with Co–Al spinel mixed oxide at 700°C, 30% KOH acted as an electrolyte. For the cyanobacterial bioreactor, a potential heterocystous blue green alga of Nostoc spp. has been used for hydrogen production and electrical energy generation. Various nutrient enrichment techniques are employed to increase the hydrogen generation efficiency of the algae. One litre free cell algal reactor attached to the fuel cell, at the anode end for hydrogen gas input, generated about 300 mV of voltage and 100 mA of current. Our present findings on the development of a low cost fuel cell with high efficiency of current output may be helpful in commercializing this technology. © 1998 John Wiley & Sons, Ltd.     

UV cross-linked dextran methacrylate--concanavalin A methacrylamide gel materials for self-regulated insulin delivery

In this study, the successful acrylic derivatization of dextran and concanavalin A (con A) to form dextran methacrylate and con A methacrylamide is shown. These derivatized acrylic monomers are then photopolymerized in the presence of a water soluble photoinitiator Irgacure® under various conditions to form covalently bonded glucose-responsive gel materials, which undergo a transformation to sol in the presence of free glucose. Rheological data have revealed that as the degree of substitution for dextran methacrylate is increased, a more elastic material is produced due to the increased covalent linkages. Some of these gel systems show negligible component loss in in vitro diffusion experiments used to simulate the behavior of the cross-linked gel, as would be used in a self-regulated insulin delivery device.     

Electronically tunable high frequency single output OTA and DVCC based meminductor

Analog Integrated Circuits and Signal Processing - This research article reports electronically tunable high-frequency meminductor based on single output operational transconductance amplifiers...     

Analysis of Frequent Failure of Oil Well Tubings Due to Formation of Longitudinal Slit

In an onshore oil field, many premature tubing failures were observed in wells operating on sucker rod pump. Failures were in the form of longitudinal crack/vertical slit. During last three to four years, the failure frequency had increased and in one well, new tubing vertically cracked in 8 months only. In the internal surface of the tubing, a longitudinal grooving was observed. The shape of the groove resembled the sucker rod and the crack was along the groove. Observation of grooved region under SEM revealed abrasion features typical of mechanical wear. Small corrosion pits were also observed on some portion of grooved region. As the well was vertical, so chance of contact between tubing and sucker rod was low. But tubing was freely suspended in the well, i.e., there was no tubing anchor which made it vulnerable for the buckling. Analytical studies showed that the failed tubing was in buckling region. On comparison of hardness, it was observed that tubing material was softer than the sucker rod. Buckling of the tubing resulted in rubbing of sucker rod against tubing wall due to which tubing had worn out in the form of groove. Wear-oxidation and oxidation-wear of tubing surface at grooved region and corrosive agents of produced water accelerated this material removal process and when the wall thickness of the tubing at groove region reduced to a point where it was not enough to withstand the hoop stresses, a longitudinal crack formed in the grooved region and tubing failed.     

Sorption behavior,thermodynamic properties and storage stability of ready-to-eat Elephant Foot Yam (<Emphasis Type="Italic">Amorphophallus</Emphasis> spp.) product: physic-chemical properties,minerals, total dietary fiber and phenolic content of stored product

The effect of osmotic dehydration in sucrose solution followed by convective dehydration on sorption isotherms and storage stability of elephant foot yam was evaluated in the present work. The equilibrium moisture content of un-treated (Hot-air-dried) and pre-treated (Osmo-air-dried) samples were determined by static gravimetric method at different temperatures (20, 30, 40, and 50?°C) and relative humidities (11–90?%). The curves obtained for sorption can be considered as type-II according to Brunauer–Emmett–Teller (BET) classification. The higher values of net-isosteric heat of sorption and heat of vaporization was observed for un-treated samples. i.e. 6.82–14.79 and 2978.28–3548.68 kJ/kmol as compared to pre-treated samples. i.e. 6.72–14.09 and 2858.33–3315.85 kJ/kmol, respectively and decreased with increase in moisture content. The experimental data revealed that enthalpy–entropy compensation theory was satisfactorily applicable to the moisture sorption behavior of the un-treated and pre-treated EFY samples. Mineral contents of fresh EFY product viz. magnesium, potassium and calcium were 190?±?1.0, 515?±?2.5 and 214?±?2.08 mg/100g, respectively. After 6 months of storage change in minerals was not significant, whereas significant increase in dietary fiber (15.95?±?0.76?19.68?±?0.45 g/100g) and slight but significant reduction in phenolic content (49.97?±?0.76–46.81?±?0.60 mgGAE/g extract) was observed.