A new approach for easy synthesis of Bacillus pseudomycoides immobilized polyvinyl alcohol (PVA)/glutaraldehyde (GA) hydrogel for application in a wastewater treatment system is reported. Optimization studies revealed that GA/PVA mass ratio of 0.03 and acidic pH of 2 were required for hydrogel synthesis and eventually for bacterial cell immobilization. The synthesized crosslinked matrix possessed a pore size suitable for microbial cell entrapment while maintaining cell accessibility to external environment for bioremediation. Possible crosslinking and bacterial cell immobilization in the hydrogel were evidenced by FTIR, XRD, and SEM studies, respectively. Further, the extent of crosslinking of GA with PVA was investigated and confirmed by transmittance and permeability experiments. The viability and proliferation of hydrogel embedded cells (after 25 days) was confirmed by confocal fluorescence microscopy which also indicated that acidic pH of polymer solution did not affect the immobilized live cells. B. pseudomycoides immobilized hydrogel were demonstrated to be effective for treatment of municipal wastewater and reduced biochemical oxygen demand (BOD), chemical oxygen demand (COD), and protein content below the recommended levels. Overall, the results from this bench-scale work show that employing bacteria-embedded PVA/GA hydrogel for the treatment of municipal wastewater yield promising results which should be further explored in pilot/field-scale studies.
This study was an attempt to document the indigenous Lepcha people’s perception on climate change-related issues in five villages of Dzongu Valley located in Kanchandzonga Biosphere Reserve, India. Personal structured questionnaire was used for interview of 300 households selected randomly. Results showed that 85 % of the households have perceived climate change, mainly in the form of increasing temperature and unpredictable pattern of rainfall. In terms of climate change-related events, 75 % of the households believed that wind is becoming warmer and stronger over the past years. Majority of the households have observed changes in crop phenology, while about 90 % agreed that the incidences of insect pest and diseases have increased over the years, especially in their large cardamom crop. A comparison of community perceptions, climatic observations and scientific literature shows that the community have correctly perceived temperature change, unpredictable occurrence of rainfall and increased incidence of insect pest and diseases, which have largely influenced the experiences and perceptions regarding climate-related events. Results reveal that households have adopted the use of locally available material as mulches against soil erosion, to conserve the soil moisture and manage soil temperature. Majority of the households have diversified their cropping system through traditional agroforestry systems and intercropping. Unfortunately, most of the households were unaware about the scientific sustainable approaches to combating impact of climate change. This documentation will aid in assessing the needs in terms of actions and information for facilitating climate change-related adaptation locally in Sikkim state of India. 相似文献
Metallic nanoparticles are finding new applications in medical, pharmaceutical, food and agriculture sectors. Applications include drug delivery, targeted cancer remedies, biomarker mapping, gene delivery and molecular imaging. This article reviews green strategies for the preparation of metallic nanoparticles, using enzymes, vitamins, monosaccharides, polysaccharides and biodegradable polymers. Microwave-assisted synthesis is detailed. Then, we review nanoparticle characterization using UV–visible spectroscopy and Fourier transform infrared spectroscopy. We also present applications for water purification. 相似文献
Environmental Science and Pollution Research - Excess fluoride (F) ion of drinking water is a major problem in many areas of India and causes harmful effects such as dental and skeletal fluorosis.... 相似文献
India has reasons to be concerned about climate change. Over 650 million people depend on climate-sensitive sectors, such
as rain-fed agriculture and forestry, for livelihood and over 973 million people are exposed to vector borne malarial parasites.
Projection of climatic factors indicates a wider exposure to malaria for the Indian population in the future. If precautionary
measures are not taken and development processes are not managed properly some developmental activities, such as hydro-electric
dams and irrigation canal systems, may also exacerbate breeding grounds for malaria. This article integrates climate change
and developmental variables in articulating a framework for integrated impact assessment and adaptation responses, with malaria
incidence in India as a case study. The climate change variables include temperature, rainfall, humidity, extreme events,
and other secondary variables. Development variables are income levels, institutional mechanisms to implement preventive measures,
infrastructure development that could promote malarial breeding grounds, and other policies. The case study indicates that
sustainable development variables may sometimes reduce the adverse impacts on the system due to climate change alone, while
it may sometimes also exacerbate these impacts if the development variables are not managed well and therefore they produce
a negative impact on the system. The study concludes that well crafted and well managed developmental policies could result
in enhanced resilience of communities and systems, and lower health impacts due to climate change. 相似文献
Studies were conducted on the spatial distribution of different stages of the mango stone weevil, Sternochetus mangiferae (Fabr.) at Hessaraghatta farm of the Indian Institute of Horticultural Research, Bangalore, during 1983. The values of various parameters of distribution showed that the eggs are distributed as a negative binomial (contagious) distribution, whereas larvae and adults follow a positive binomial (random) distribution. It is suggested that the change in distribution may be due to the lower population densities in larval and adult stages. 相似文献
The present study was designed with an aim to observe the effect of increasing urbanization and traffic activity on the physiology of a foliose lichen, Phaeophyscia hispidula (Ach.) Essl., collected from 13 different localities, growing in their natural habitat, in Pauri and Srinagar, two cities in the Himalayas. Six parameters i.e., Chl. a, Chl. b, total pigment, chlorophyll degradation, carotenoid and total protein content, proved the most useful to assess air pollution, were measured. Chlorophyll content and protein content are an efficient parameter to measure the air quality of a region. The study indicates that P. hispidula is pollution tolerant (adaptation) and able to withstand local emissions from vehicle exhausts. 相似文献