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11.
A GFP-based bacterial biosensor with chromosomally integrated sensing cassette for quantitative detection of Hg(II) in environment 总被引:3,自引:0,他引:3
Himanshu Priyadarshi Absar Alam Gireesh-Babu P Rekha Das Pankaj Kishore Shivendra Kumar Aparna Chaudhari 《环境科学学报(英文版)》2012,24(5):963-968
A mercury biosensor was constructed by integrating biosensor genetic elements into E. coli JM109 chromosome in a single copy number, using the attP/attB recombination mechanism of λphage. The genetic elements used include a regulatory protein gene (merR) along with operator/promoter (O/P) derived from the mercury resistance operon from pDU1358 plasmid of Serratia marcescens. The expression of reporter gene gfp is also controlled by merR/O/P. Integration of the construct into the chromosome was done to increase the stability and precision of the biosensor. This biosensor could detect Hg(II) ions in the concentration range of 100-1700 nmol/L, and manifest the result as the expression of GFP. The GFP expression was significantly different (P ≤ 0.05) for each concentration of inducing Hg(II) ions in the detection range, which reduces the chances of misinterpretation of results. A model using regression method was also derived for the quantification of the concentration of Hg(II) in water samples. 相似文献
12.
Source apportionment study of PM10 (Particulate Matter) in a critically polluted area of Jharia coalfield, India has been carried out using Dispersion model, Principle Component Analysis (PCA) and Chemical Mass Balance (CMB) techniques. Dispersion model Atmospheric Dispersion Model (AERMOD) was introduced to simplify the complexity of sources in Jharia coalfield. PCA and CMB analysis indicates that monitoring stations near the mining area were mainly affected by the emission from open coal mining and its associated activities such as coal transportation, loading and unloading of coal. Mine fire emission also contributed a considerable amount of particulate matters in monitoring stations. Locations in the city area were mostly affected by vehicular, Liquid Petroleum Gas (LPG) & Diesel Generator (DG) set emissions, residential, and commercial activities. The experimental data sampling and their analysis could aid understanding how dispersion based model technique along with receptor model based concept can be strategically used for quantitative analysis of Natural and Anthropogenic sources of PM10. 相似文献
13.
Pankaj Kumar Vandana Mishra Saiyami Bhardwaj Shafali Garg Ludovic F. Dumée Radhey Shyam Sharma 《环境质量管理》2023,32(4):9-17
Sectorial approach for monitoring heavy metal pollution in rivers has failed to report realistic pollution status and associated ecological and human health risks. The increasing spread of heavy metals from different sources and emerging risks to human and environmental health call for reexamining heavy metal pollution monitoring frameworks. Also, the sources, spread, and load of heavy metals in the environment have changed significantly over time, requiring consequent modification in the monitoring frameworks. Therefore, studies on heavy metal monitoring in rivers conducted in the last decade were evaluated for experimental designs, research frameworks, and data presentations. Most studies (∼99%) (i) lacked inclusiveness of all environmental compartments; (ii) focused on “one pollutant – one/two compartment” or sometimes “one pollutant – one compartment – one effect” approach; and (iii) remained “data-rich but information poor.” An ecological approach with integrative system thinking is proposed to develop a holistic approach for monitoring river pollution. It is visualized that heavy metal monitoring, risk analyses, and water management must incorporate tracking pollutants in different environmental compartments of a river (water, sediment, and floodplain/bank soil) and consider correlating it with riverbank land use. The systems-based pollution monitoring and assessment studies will reveal the critical factors that drive heavy metals pollutant movement in ecosystems and associated potential risks to the environment, wildlife, and humans. Also, water quality and pollution indexing tools would help better communicate complex pollution data and associated risks among all stakeholders. Therefore, integrating systems approaches in scientific- and policy-based tools would help sustainably manage the health of rivers, wildlife, and humans. 相似文献
14.
Pankaj Anjankar Sanjay Lakade Atul Padalkar Sandeep Nichal Yuvarajan Devarajan Natrayan Lakshmaiya Naveen Subbaiyan 《环境质量管理》2023,33(1):61-69
Energy, cost, and environmental concerns play a vital role in understanding governing parameters of distributor design in falling film evaporators. Distributor design is a hidden parameter in many experimental papers. The uniform distribution of liquid refrigerant over the tube bundle mostly depends on two-phase liquid refrigerant and vapor refrigerant. This work conducted experiments with two distribution systems with and without separation of liquid-vapor refrigerant after expansion valve for the same evaporator capacity with R134a as a refrigerant. Results reveal that; separating vapor refrigerant has a positive impact on the approach of the evaporator with an open system distributor arrangement. The highest delta T and lowest practice are found at a heat flux of 13.97 kW/m2 with an available system distributor compared to a closed system with a heat flux of 14.25 kW/m2. The open system arrangement in the distributor is the novel parameter for distributor design, ensuring uniform distribution with minimum pressure drop and dry suction. An open system distributor has an average 16.1% capacity increase over a closed system. The experimental analysis helps to understand different parameters for the design of distributors in falling film evaporators for uniform distribution. 相似文献
15.
Pankaj Kumar Maki Tsujimura Takanori Nakano Tokumasu Minoru 《Environmental geochemistry and health》2013,35(2):239-250
Considering the current poor understanding of the seawater–freshwater (SW–FW) interaction pattern at dynamic hydro-geological boundary of coastal aquifers, this work strives to study tidal effect on groundwater quality using chemical tracers combined with environmental isotopes. In situ measurement data of electrical conductivity and groundwater level along with laboratory measurement data of hydro-chemical species were compared with tidal level data measured by Hydrographic and Oceanographic Department, Saijo City, Japan for time series analysis. Result shows that diurnal tides have significant effect on groundwater level as well as its chemical characteristics; however, the magnitude of effect is different in case of different aquifers. Various scatter diagrams were plotted in order to infer mechanisms responsible for water quality change with tidal phase, and results show that cations exchange, selective movement and local SW–FW mixing were likely to be the main processes responsible for water quality changes. It was also found that geological structure of the aquifers is the most important factor affecting the intensity of tidal effect on water quality. 相似文献
16.
Pal Swades Singha Pankaj 《Environmental science and pollution research international》2023,30(5):11634-11660
Environmental Science and Pollution Research - Flow modification pursuing dams is widely found. Some works also focused on its impact on floodplain wetland hydrology. However, how this change can... 相似文献
17.
Najam Akhtar Shakil Jitendra Kumar Pankaj Alka Pandey Vivek Ahluwalia Manish K. Singh 《Journal of environmental science and health. Part. B》2013,48(4):344-349
A series of novel N-alkyl-N-[1-(2-hydroxyphenyl) ethyl]amines were synthesized as potential new agents to control pests. Their structures were confirmed on the basis of IR, NMR and elemental analyses. Six new N-alkyl-N-[1-(2-hydroxyphenyl) ethyl]amines were prepared by reduction of corresponding Schiff bases using sodium borohydride in 80–87 % yields. These compounds were tested for their antifungal activity against two pathogenic fungi viz., Rhizoctonia bataticola ITCC 0482 and Sclerotium rolfsii ITCC 5226 and for insecticidal activity against insects of stored grain pest Callosobruchus analis. Fungicidal bioassay revealed that compound N-Decyl-N-[1-(2-hydroxyphenyl)ethyl]amine, was highly effective against R. bataticola (ED50 6.86 mg L?1) which was comparable with that of commercial fungicide hexaconazole (ED50 6.35 mg L?1). Also compounds N-Heptyl-N-[1-(2-hydroxyphenyl)ethyl]amine, N-Octyl-N-[1-(2-hydroxyphenyl)ethyl]amine and N-Nonyl-N-[1-(2-hydroxyphenyl)ethyl]amine displayed promising fungitoxicity against same pathogen. However, compound N-Heptyl-N-[1-(2-hydroxyphenyl)ethyl]amine was also found to be effective against S. rolfsii (ED50 4.92 mg L?1 as against 1.27 mg L?1 for hexaconazole). Compound N-Hexyl-N-[1-(2-hydroxyphenyl)ethyl]amine was most effective as insecticide followed by compound N-Octyl-N-[1-(2-hydroxyphenyl)ethyl]amine. LC50 values for these compounds were 155.0 and 275.0 mg L?1 respectively as against 36.70 mg L?1 for commercial insecticide dichlorovos. The results obtained from bioassays indicate that this class of compounds can be utilized for the design of new substances endowed with pesticidal activities. 相似文献
18.
Reena Sharma Susheel Kalia Balbir S. Kaith Amit Kumar Pankaj Thakur D. Pathania Manoj K. Srivastava 《Journal of Polymers and the Environment》2017,25(2):176-191
Ggum-based conducting hydrogels possessing dye removal and antibacterial property were developed by two-step free-radical aqueous polymerization method. Conductivity was introduced with polyaniline (PANI) chains incorporated within the crosslinked network of Ggum-poly(itaconic acid) superabsorbent. The material properties of the synthesized samples were characterized using FTIR spectroscopy, thermal analysis and scanning electron microscopy techniques. Results showed that synthesized samples exhibited the best antibacterial activity against Gram-positive bacteria. Synthesized samples were found to be effective in removal of toxic methylene blue (MB) dye from the waste water. The adsorption kinetics of superabsorbents has been described by using pseudo first and pseudo second order kinetics models. Furthermore, application of hydrogels to improve the water retention properties of different soils was also studied for agricultural purpose. 相似文献
19.
Maurya Pankaj Kumar Mondal Soumila Kumar Vinod Singh Shailendra Pratap 《Environmental science and pollution research international》2021,28(36):49327-49342
Environmental Science and Pollution Research - The total number of inhabitants on the Earth is estimated to cross a record number of 9 × 103 million by 2050 that present a unique challenge to... 相似文献
20.
Anand Uttpal Adelodun Bashir Cabreros Carlo Kumar Pankaj Suresh S. Dey Abhijit Ballesteros Florencio Bontempi Elza 《Environmental Chemistry Letters》2022,20(6):3883-3904
Almost all aspects of society from food security to disease control and prevention have benefited from pharmaceutical and personal care products, yet these products are a major source of contamination that ends up in wastewater and ecosystems. This issue has been sharply accentuated during the coronavirus disease pandemic 2019 (COVID-19) due to the higher use of disinfectants and other products. Here we review pharmaceutical and personal care products with focus on their occurrence in the environment, detection, risk, and removal.
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