74 research outputs found
MMaJIC (Microgravity Materials Joining Investigation Chamber)
No abstract availabl
Not Available
Not AvailableThe oxytetracycline is being used in aquaculture industry as a broad spectrum antimicrobial agent with bacteriostatic property. Unregulated and indiscriminate usage of antibiotics leads to their buildup in the environment. Physical and chemical methods to remediate or remove these antibiotics are ineffective. The present study aims at the mycotic bioremediation of the oxytetracycline by Pleurotus ostreatus. It was cultured in the potato dextrose broth for 7 to 14 days and used in the experiment with fungal load of 104 CFU ml-l . In vitro soil based lab study was performed in triplicate at four different salinities 1, 15, 30 and 45 ppt, with three different concentrations of oxytetraycline (50, 150
and 250 mg L-1 ), and treated with P. ostreatus. The suspended water samples were collected at periodic intervals of 2, 7 and 14 days after treatment and estimated for antibiotic in treatment and control. It was found that the P. ostreatus significantly (p ≤0.05) degraded the antibiotic at all salinities. The reduction of drug ranged from 58-76% (2 days), 45-78% (7 days) & 36-62% (14 days) at 1ppt, 32-34% (2 days), 58-71% (7 days) & 48-80% (14 days) at 15 ppt, 52-73% (2 days), 27- 61% (7 days) & 44-62% (14 days) at 30 ppt, and 32-68% (2 days), 44-66% (7 days) & 44- 64% (14 days) at 45 ppt compared to the control.Not Availabl
Microbiologically influenced corrosion in dairy effluent
In the dairy industry mild steel is used as the construction material for the effluent treatment plants,
pipelines, reinforcement in concrete structures etc. The steel exposed to the dairy effluent faces corrosion due to the
microbes. In the present study the role of microbes in dairy effluent on the corrosion of mild steel has been investigated.
Pseudomonas sp., Streptococcus sp., Micrococcus sp., Bacillus sp., Neisseria sp. and Lactobacillus sp. were identified
in dairy effluent. Corrosion rate has been estimated by weight loss measurements and polarization technique. The
Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD) studies were found helpful in
investigating the chemical pathway leading to the formation of corrosion products on the mild steel during fermentation.
Initiation of pitting corrosion was noticed on steel specimens by scanning electron microscope (SEM). A mechanism
has been proposed for microbiologically influenced corrosion in dairy effluent
Study on strength and corrosion performance for steel embedded in metakaolin blended concrete/mortar
It is an undeniable fact that concrete is the most widely used man-made construction material in the world today, and will remain so
for decades to come. The popularity of concrete is largely due to the abundance of raw material, low manufacturing and maintenance
cost, excellence in compression, and corrosion aspects, durability to weathering and fire hazards, versatility in forming various shapes
and its unlimited structural applications in combination with steel reinforcement. However, the cement industry is also highly energy
intensive, and the emission of carbon dioxide during cement manufacturing has created enormous environmental concerns. There has
also been an increase in the number of incidents where concrete structures experienced severe deterioration in extreme environments.
All these factors have contributed pressures from various quarters to reduce cement consumption, and to intensify research in exploring
the possibilities of enhancing strength, durability and corrosion reduction through the use of pozzolans as supplementary cementing
materials. The utilization of calcined clay in the form of metakaolin as a pozzolan for concrete has received considerable interest in recent
years. The use of metakaolin as a mineral admixture for concrete is a well documented practice. Metakaolin is a quality enhancing pozzolan
for concrete. It is manufactured from kaolin which is abundance in India and other parts of the country.
In the present investigation mechanical property and corrosion behavior of carbon steel using metakaolin (5–20%) as partial replacement
in ordinary Portland cement (OPC). Compressive strength, resistivity, ultra pulse velocity, open circuit potential, studies on water
absorption, weight loss were studied. It was found that up to 15% replacement of metakaolin in OPC improves the mechanical properties
of concrete. Corrosion of carbon steel improved by the addition of metakaolin up to 15%
From Research-to-Practice: An Adaptation and Dissemination of the COMPASS Program for Home Care Workers
The COMmunity of Practice And Safety Support (COMPASS) program was developed to prevent injuries and advance the health and well-being of home care workers. The program integrates elements of peer-led social support groups with scripted team-based programs to help workers learn together, solve problems, set goals, make changes, and enrich their supportive professional network. After a successful pilot study and randomized controlled trial, COMPASS was adapted for the Oregon Home Care Commission’s training system for statewide dissemination. The adapted program included fewer total meetings (7 versus 13), an accelerated meeting schedule (every two weeks versus monthly), and a range of other adjustments. The revised approach was piloted with five groups of workers (total n = 42) and evaluated with pre- and post-program outcome measures. After further adjustments and planning, the statewide rollout is now in progress. In the adaptation pilot several psychosocial, safety, and health outcomes changed by a similar magnitude relative to the prior randomized controlled trial. Preliminary training evaluation data (n = 265) show high mean ratings indicating that workers like the program, find the content useful, and intend to make changes after meetings. Facilitating factors and lessons learned from the project may inform future similar efforts to translate research into practice
Environmental effects on concrete using ordinary and pozzolana portland cement
Wastewater treatment plant consists of pipe lines and lift stations. These plants consist of concrete pipes,
manholes, pump stations, interceptors and wet wells. Entire wastewater (WW) system is forced to chemical attack due to the presence of sulphate and acid available in WW. It leads to the damage in the interior wall or structure of a sewer pipe and lift station. A concrete structure when exposed to different environments, the life of the structure is drastically reduced. Main cause of the deterioration is corrosion or erosion. The defective structures are replaced periodically which leads to indirect loss in the national growth. In other words, the failure of these structures may lead to invest more on the repair and rehabilitation.
In this study, the strength of the concrete in various environments has been investigated using different
techniques such as compressive strength, flexural test, rapid chloride permeability, weight loss measurements,
linear polarization and open circuit potential. Microbiological examinations were also analyzed. Two types of cement namely Ordinary Portland Cement (OPC) and Portland Pozzolana Cement (PPC) with one mix ratio were used for complete study. Concrete specimens exposed in three environments namely: normal water (NW Potable water), domestic sewage water (DSW) and textile wastewater (TWW). From the results, it is observed that PPC exposed in different media shows better performance than OPC in both
mechanical and electrochemical studie
Surface morphology, corrosion resistance and in vitro bioactivity of P containing ZrO2 films formed on Zr by plasma electrolytic oxidation
The present work was aimed at developing the corrosion resistant and bioactive oxide film on zirconium by plasma electrolytic oxidation in phosphate electrolyte. The effect of plasma electrolytic oxidation treatment time on surface morphology and corrosion resistance of the oxide films was further investigated. The phase composition, surface morphology, thickness and elemental composition of the oxide films were analyzed by X-ray diffraction and scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy. The corrosion behavior of substrate and oxide films in simulated body fluid environment was studied by open circuit potential and potentiodynamic polarization tests. The apatite forming ability of the oxide film was evaluated after immersing in simulated body fluid for 14 days. X-ray diffraction patterns show that the oxide films predominantly comprised of monoclinic zirconia with a small amount of tetragonal zirconia. With prolonging treatment time, phase transformation of tetragonal to monoclinic zirconia was observed. Scanning electron microscopy results show that for a treatment time of 2–8 min, uniform and highly dense oxide films, thickness varying from 3 to 14 μm with no obvious pores were formed and the phosphorous content in the films was found to be in the range of 2.8–6.8 at.%. Corrosion test results reveal that all oxide films improved their corrosion resistance especially in terms of pitting potential and showed superior passivity in simulated body fluid environment. Bioactivity test results confirm that plasma electrolytic oxidation treated zirconium was fully covered by apatite layer in simulated body fluid medium. The incorporation of phosphorous in oxide film during coating process significantly enhanced the apatite forming ability of zirconium. In conclusion, among all the plasma electrolytic oxidation coated samples, the 6 min coated zirconium with high corrosion resistance and bioactivity is a potential candidate as orthopedic implants
Mechanochemical synthesis of nanocrystalline fluorinated hydroxyapatite
10.1142/S0219581X05003681International Journal of Nanoscience44643-64
- …