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1.
P. Noorunnisa Khanam H. P. S. Abdul Khalil M. Jawaid G. Ramachandra Reddy C. Surya Narayana S. Venkata Naidu 《Journal of Polymers and the Environment》2010,18(4):727-733
The variation of mechanical properties such as tensile and flexural properties of randomly oriented unsaturated polyester
based sisal/carbon fibre reinforced hybrid composites with different fibre weight ratios have been studied. The chemical resistance
test of these hybrid composites to various solvents, acids and alkalies were studied. The effect of NaOH treatment of sisal
fibres on the tensile, flexural and chemical resistance properties of these sisal/carbon hybrid composites has also been studied.
The hybrid composites showed an increase in tensile and flexural properties with increase in the carbon fibre loading. The
tensile properties and flexural properties of these hybrid composites have been found to be higher than that of the matrix.
Significant improvement in tensile properties and flexural properties of the sisal/carbon hybrid composites has been observed
by alkali treatment. The chemical resistance test results showed that these untreated and alkali treated hybrid composites
are résistance to all chemicals except carbon tetra chloride. Hand lay-up technique was used for making the composites and
tests are carried out by using ASTM methods. 相似文献
2.
N. Mithil Kumar K. Varaprasad G. Ramachandra Reddy G. Siva Mohan Reddy Y. Sivabharathi G. Venkata Subba Reddy S. Venkata Naidu 《Journal of Polymers and the Environment》2011,19(1):225-229
Synthesis and characterization of novel biodegradable, water soluble and optically active DL-malic acid (DMA) and citric acid
(CA) copolymers were studied for possible use as antibacterial agents. The copolymers were synthesized by direct bulk melt
condensation in the absence of a catalyst above 150 °C. Characterization of obtained copolymers was carried out with the help
of infrared absorption spectra, differential scanning calorimetry and thermo gravimetric analysis. The antibacterial activity
of copolymers against bacteria was investigated. The results obtained shows the above copolymers possess a broad wound dressing
activity against different types of bacteria and may be useful as antibacterial agents. 相似文献
3.
Sudha Rani Batchu Venkata R. Panditi Piero R. Gardinali 《Journal of environmental science and health. Part. B》2013,48(3):200-211
The photochemical fate of seven sulfonamides was investigated in matrices representative of natural water bodies under various light sources. Fundamental photolysis parameters such as molar absorption coefficient, quantum yield (QY) and first-order rate constants were determined. The photolysis decay rate was dependent on the protonation state of the molecule, pH of the water sample and dissolved organic matter. Natural organic matter was the most significant factor in the indirect photolysis of sulfonamides. Half-lives were in the range of minutes at 254 nm to days under natural sunlight. Under natural sunlight, all sulfonamides showed higher removal rates in natural waters implying that indirect photolysis is the predominant mechanism. 相似文献
4.
A. Bhagyalakshmi S. Venkata Reddy R. Ramamurthi P. S. Reddy 《Chemistry and Ecology》1995,11(2):97-104
Toxicity of an organochloride insecticide, hexachlorocyclohexane (HCH) on the alterations in the growth and silk qualities of silkworm, Bombyx mori L were investigated. HCH yielded higher growth constants (K), indicating impairment of growth of silkworms and silk gland. the decrement in fibroin content is significant. HCH treatment also resulted in considerable reduction in the cocoon, pupal and shell weights, survival and emergence of pupae and number of eggs laid and deterioration in quality and quantity of silk thread. 相似文献
5.
Sharma Baby Kumari Nilima Mathur Shruti Sharma Vinay 《Environmental science and pollution research international》2022,29(1):312-331
Environmental Science and Pollution Research - The projected increase of the global textile industry to USD1002.84 billion in 2027 indicates a simultaneous increase in water pollution due to... 相似文献
6.
Microbial degradation of pyridine using Pseudomonas sp. and isolation of plasmid responsible for degradation 总被引:11,自引:0,他引:11
Mohan SV Sistla S Guru RK Prasad KK Kumar CS Ramakrishna SV Sarma PN 《Waste management (New York, N.Y.)》2003,23(2):167-171
Pseudomonas (PI2) capable of degrading pyridine was isolated from the mixed population of the activated sludge unit which was being used for treating complex effluents, the strain was characterized. Aerobic degradation of pyridine was studied with the isolated strain and the growth parameters were evaluated. Pyridine degradation was further conformed by chromatography (HPLC) analysis. The process parameters like biomass growth and dissolved oxygen consumption were monitored during pyridine degradation. In order to conform with the plasmid capability to degrade pyridine, the requisite plasmid was isolated and transferred to DH 5alpha Escherichia coli. The subsequent biodegradation studies revealed the ability of the transformed plasmid capability to degrade the pyridine. 相似文献
7.
Venkata Ramanaiah Solanki Mohd Masood Hussain S. Sabita Raja 《Environmental monitoring and assessment》2010,163(1-4):411-419
A systematic investigation of variations in some nutrient levels at Pandu Lake from August 2002 to July 2004 was carried out. The untreated domestic wastes from various parts of Bodhan town are directly discharged into Pandu Lake leading to gross pollution. Therefore present investigation was under taken to assess the magnitude of sewage pollution by monitoring key water quality parameters dissolved oxygen, biological oxygen demand, alkalinity, calcium, nitrates and phosphates etc. Monthly water samples were collected from three different sampling stations. Low Dissolved oxygen and high biological oxygen demand, elevated Nitrates and Phosphates levels were found, which gives the information about conversion of this water body from oligotrophic to eutrophic nature. Phosphates were found to be in the range of 0.9 to 4.0 mg/L. Nitrates were found to be higher in Pandu Lake and their number is more in summer, and suitable explanation was given. Nitrates were found to be in range between 24.8mg/L to 71.2mg/L. Data on various chemical characteristics vary at different sites in different months in Pandu Lake. Some of the characteristics like Dissolved Oxygen, Biological Oxygen Demand, Nitrates, Phosphates and nutrient loading are contributing to eutrophication process in this lake and the lake seems to be eutrophic through out the year. 相似文献
8.
Shruti Pavagadhi Raghu Betha Shriram Venkatesan Rajasekhar Balasubramanian Manoor Prakash Hande 《Environmental science and pollution research international》2013,20(4):2569-2578
Air particulate matter (PM) samples were collected in Singapore from 21 to 29 October 2010. During this time period, a severe regional smoke haze episode lasted for a few days (21–23 October). Physicochemical and toxicological characteristics of both haze and non-haze aerosols were evaluated. The average mass concentration of PM2.5 (PM with aerodynamic diameter of ≤2.5 μm) increased by a factor of 4 during the smoke haze period (107.2 μg/m3) as compared to that during the non-smoke haze period (27.0 μg/m3). The PM2.5 samples were analyzed for 16 priority polycyclic aromatic hydrocarbons (PAHs) listed by the United States Environmental Protection Agency and 10 transition metals. Out of the seven PAHs known as potential or suspected carcinogens, five were found in significantly higher levels in smoke haze aerosols as compared to those in the background air. Metal concentrations were also found to be higher in haze aerosols. Additionally, the toxicological profile of the PM2.5 samples was evaluated using a human epithelial lung cell line (A549). Cell viability and death counts were measured after a direct exposure of PM2.5 samples to A459 cells for a period of 48 h. The percentage of metabolically active cells decreased significantly following a direct exposure to PM samples collected during the haze period. To provide further insights into the toxicological characteristics of the aerosol particles, glutathione levels, as an indirect measure of oxidative stress and caspase-3/7 levels as a measure of apoptotic death, were also evaluated. 相似文献
9.
P. Noorunnisa Khanam H. P. S. Abdul Khalil G. Ramachandra Reddy S. Venkata Naidu 《Journal of Polymers and the Environment》2011,19(1):115-119
In this study, effect of fibre surface treatment on tensile, flexural and chemical resistance properties were studied for
sisal fibre reinforced composites. Natural ligno cellulosic sisal fibre reinforced composites were prepared by different surface
treatments by hand lay-up method. Fibre surface treatments were carried out to produce good interface between the fibre and
the matrix to improve the mechanical properties. Fibre surface treatments were done by boiled the sisal fibres in different
% of NaOH and treated the fibres in different % of NaOH, treated in acetic acid and methanol. Unsaturated polyester resin
was used as the matrix for preparing the composites. For comparison, these properties for untreated sisal fibre reinforced
composites were also studied. From the results it was observed that 18% aqueous NaOH boiled sisal fibre reinforced composites
have higher tensile, flexural properties than other composites. Untreated sisal fibre composites show lower properties than
treated composites. Chemical resistance properties indicate that all sisal fibre reinforced composites are resistance to all
chemicals except carbon tetra chloride. The tests are carried out as per the ASTM standards. 相似文献
10.
Autecology of the common mormon butterfly,Papilio polytes (Lepidoptera : Rhopalocera : Papilionidae)
Atluri JB Ramana SP Reddi CS 《Journal of environmental biology / Academy of Environmental Biology, India》2002,23(2):199-204
The adults of the common mormon butterfly Papilio polytes Linn. feed on a variety of floral species. The larval food plants in the study area included Citrus limon and Murraya koenigii both of the family Rutaceae. The eggs are laid singly, and the hatching time is three days. The larvae pass through five instars. The larval growth is directly correlated with the quantity of food consumed. The AD (approximate digestibility) values decreased from first instar to the last, whereas the ECD (efficiency of conversion of digested food) and ECI (efficiency of conversion of ingested food) values increased, thus bearing an inverse relationship with AD. The development time from egg to adult is 28-30, giving 11-12 generations in a year, but with better breeding during August-February. Thus P. polytes is multivoltine. 相似文献