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HPTLC Based Screening of -Sitosterol from Andrographis paniculata
2019
Rajeshwari Prabha Lahare and Anil Kumar
Sterols are secondary metabolites of plants known for their inhibitory effects on cancer cell growth, lower cholesterol and enhance immunity. b-sitosterol belongs to phytosterol which enhances antioxidant enzymes and thus reduces the oxidative stress. In present experiment, b-sitosterol was detected from Andrographis paniculata belonging to family Acanthaceae by using HPTLC. The plant is popularly known as Kalmegha having multiple pharmacological properties used for treatment of several diseases. Leaf, stem and root extracts prepared in chloroform, methanol and petroleum ether were used for detection of b-sitosterol from the plant. The chromatography was performed on TLC plates coated with Al silica gel 60 F254 and solvents used for mobile phase was toluene:ethyl acetate:formic acid (15:4.5:1.5). After development, the plates were derivatized with 10% methanolic sulphuric acid, scanned and quantified at 510 nm. The results showed the presence of b-sitosterol in all the parts with Rf value 0.62. Calibration curve was prepared and the amount of b-sitosterol was quantified in the extracts by comparing the respective peak areas with that of the standard. The correlation coefficient for b-sitosterol against reference sample was found significant (r= 99.769057%) for the concentration range of 0.5 to 4.0 µg. Leaf methanol extract showed the highest concentration of b-sitosterol, i.e., 147.6 µg/mL. The extraction efficiency of b-sitosterol was found higher in methanol followed by petroleum ether and chloroform extract. Thus, our finding shows that Andrographis paniculata has a significant concentration of b-sitosterol, which may be useful for pharmacological application against cancer, hypercholesterolemia, inflammation and for angiogenesis process.
显示更多 [+] 显示较少 [-]Control of Air Pollutants Emission and Improvement of Incineration Rate During Incineration of Oily Sludge-Based Briquette
2019
Mingming Du, Fengchao Wang, Jinling Li, Tao Yu and Chengtun Qu
The incineration technology of oily sludge-based briquette makes great contributions to oily sludge treatment. In order to resolve these problems, air pollutants (SO2 and organic gas) emission and low incinerating rate during the briquette incineration, the effects of additives (CaCO3, CaO; K2CO3, Na2CO3, NaCl; KMnO4, KNO3, NaNO3; Fe2O3, KClO3) on the generating gas and incinerating rate during incineration were studied. The results show that CaCO3 is more effective than CaO for fixing sulphur into residue, and K2CO3 improved the sulphation efficiency of calcium-based additives, which is more useful than NaCl and Na2CO3 did. As for the incinerating rate of briquette, KMnO4 is more effective than KNO3 and NaNO3. The maximum of incinerating rate of briquette is improved from 0.38 to 0.6 g/ min and Fe2O3 and KClO3 can apparently reduce the release of organic gas during the incineration of briquette. But KClO3 can greatly reduce the release of sulphur. When the adding amount of CaCO3, K2CO3, KMnO4 and KClO3 is 16‰, 12‰, 18‰, 6‰ respectively in the process of briquette preparation, the sulphation efficiency reached the maximum of 95.3%, and there is still an extremely small amount of organic gas in flue gas. CaCO3, K2CO3, KMnO4 and KClO3 used in emission control of air pollutants and full combustion of briquette during incineration of oily sludge based-briquette, demonstrates high efficiency and low emission compared to other additives tested in this study.
显示更多 [+] 显示较少 [-]Comparison for the Adsorption of Catechol and Hydroquinone on Activated Carbon Fibre: Kinetic Analysis
2019
Mingzhao Shen, Meiya Zhu, Jintao Sun, Yunlong Zhang, Rong Li, Fang Niu, Shiying Li, Xiao Mi and Guoting Li
Catechol and hydroquinone are widely applied in industrial synthesis while they are typical toxic organic pollutants. Efficient adsorptive removal of catechol and hydroquinone is highly needed. In this research, activated carbon fibre (ACF) was used for the kinetic removal of the two pollutants. As catechol and hydroquinone have different pKa values, it was found that the highest uptake of catechol and hydroquinone was observed at pH 11.0 and 5.0, respectively. The adsorption kinetics for catechol and hydroquinone were compared. The removal of hydroquinone is higher than that of catechol at almost all the pH conditions. At pH 7.0, the uptake of catechol and hydroquinone on ACF were 125.8 and 200.4 mg/g, respectively. As both Elovich and pseudo-second-order kinetic models could better describe the adsorption process, the adsorption of catechol and hydroquinone onto ACF might be chemisorption. The rate determining step might be diffusive in nature for the uptake of catechol and hydroquinone. Linear pseudo-second-order kinetic model fitted the experimental data better than pseudo-first-order kinetic model. The presence of natural organic matter, humic acid, could inhibit the uptake of catechol and hydroquinone on ACF profoundly.
显示更多 [+] 显示较少 [-]Retrieval of the Canopy Chlorophyll Density of Winter Wheat from Canopy Spectra Using Continuous Wavelet Analysis
2019
Qingkong Cai, Erjun Li, Jiechen Pan and Chao Chen
Continuous wavelet analysis (CWA) has been applied to leaf-scale spectral data for quantifying leaf chlorophyll content, but its application to canopy-scale spectral data for estimating the canopy chlorophyll density (CCD) of winter wheat at different growth stages requires further analysis. This study aims to estimate CCD by applying CWA to the canopy spectra of 185 samples from Guanzhong Plain, China. The five most informative wavelet features related to CCD were identified using the CWA method. Meanwhile, 10 commonly used spectral indices were selected to compare with the CWA method. Two partial least square regression (PLSR) models based on wavelet features and spectral indices were developed and compared. Results showed that the PLSR model using wavelet features (R2 = 0.64, RMSE = 0.43 g/m2) was better than that using spectral indices (R2 = 0.57, RMSE = 0.48 g/m2) and wavelet features were less sensitive to the growth stage variation than spectral indices. This result suggested that the CWA approach can derive robust wavelet features and was more effective than spectral indices for predicting CCD from canopy-scale spectral data for an agricultural ecosystem.
显示更多 [+] 显示较少 [-]Influence of Tourism Industry Development on Environmental Pollution and EcoCompensation Measures in Chongqing City, China
2019
Jixia Zhou
Ecological environment is not only the basis for human survival and development but also the carrier of tourism industry development. However, such a basis for survival and development of the tourism industry is damaged given the excessive pursuit of economic benefits and neglect of ecological environmental protection in tourist attractions. Eco-compensation measures protect the tourism ecosystem and coordinate the contradiction between tourism industry development and ecological protection. Thus, the sustainable development of the tourism industry can be facilitated. In this study, research on environmental pollution caused by the tourism industry in Chongqing City, China, and relevant eco-compensation measures were first reviewed. Second, an empirical study on the relations of total tourism revenues with waste gas emission, wastewater discharge, and industrial solid waste emission in Chongqing City was conducted using a vector autoregression model. The study findings show that tourism industry development can influence environmental pollution slightly and that an eco-compensation mechanism coordinates the relationship between tourism and ecological environment. Tourism economic growth has long-term equilibrium relations and mutual Granger causality with waste gas emission, wastewater discharge, and industrial solid waste emissions. The conclusions provide a reference to understand the dynamic relations between tourism industry development and environmental pollution, construct a guarantee system for tourism eco-compensation mechanism, and achieve sustainable development of tourism industry and environmental protection.
显示更多 [+] 显示较少 [-]Heavy Metal Accumulation in Some Fishes Preferred for Consumption by Egrets in Odisha, India
2019
Bibhu Prasad Panda, Biswajit Panda, Siba Prasad Parida, Biswajita Mahapatra, Aditya Kishore Dash and Abanti Pradhan
The reduction of wetlands due to the increase of urbanization and industrialization has been an emerging global concern and is a threat to the fish population. Fishes have been proved as excellent indicators of heavy metal contamination of the aquatic ecosystems. The present research aims to determine the metal accumulation in fishes of different wetlands. Fish samples were collected for analysis of different metals like lead (Pb), chromium (Cr), copper (Cu) and zinc (Zn) by atomic absorption spectrophotometer. Pb concentration varies from 0.41-44.33 µg/g and found to be highest at Hirakud, whereas Cr, Cu and Zn were highest at Koraput which vary from 1.3-10.36 µg/g, 1.29-4.17 µg/g and 20.97-54.99 µg/g, respectively.
显示更多 [+] 显示较少 [-]Simultaneous Removal of Cu(II) and 1-Naphthol in Wastewater by Magnetic Nanoparticle-Graphene Oxide Composites
2019
Jie Luo, Donglin Zhao, Linxia Wang, Abdullah M. Asiri and Khalid A. Alamry
A graphene-based magnetic composite (Fe3O4/GO) was prepared and used for simultaneous removal of Cu(II) and 1-naphthol. The composite was characterized by SEM, TEM, XRD, FT-IR and Raman. Electron microscopy reflected that Fe3O4 spheres were dispersed on graphene layers. The pseudo-second-order kinetic and Langmuir isotherm models could best describe the sorption kinetics and isotherms. The sorption of Cu(II) and 1-naphthol increased with increasing temperature, and thermodynamic parameters calculated from temperature dependent sorption revealed that sorption of Cu(II) and 1-naphthol on Fe3O4/GO was spontaneous and endothermic. The results indicated that Fe3O4/GO can be utilized as potential adsorbents for purification of co-contaminated water systems.
显示更多 [+] 显示较少 [-]Biomonitoring of Water Bodies in Metro Manila, Philippines Using Heavy Metal Analysis and Erythrocyte Micronucleus Assay in Nile Tilapia (Oreochromis niloticus)
2019
Zeba F. Alam, Charilen Kei V. Concepcion, Johnray D. Abdulrahman and Miguel Alvaro S. Sanchez
Environmental biomonitoring of water bodies is routinely done to assess the ecological state of aquatic systems by detecting the hazardous and genotoxic pollutants. In this study, a combination of atomic absorption spectroscopy and the fish micronucleus assay was used to determine and compare the genotoxic potential of water bodies specifically the two Esteros namely, Estero de Vitas and Estero de Paco, which are part of the Pasig River System, Philippines. As part of the strategy, the Esteros are being rehabilitated to control pollution in the river systems whereby Estero de Paco was recently rehabilitated, whereas, Estero de Vitas is still largely neglected. The elevated levels of micronuclei and nuclear abnormalities were observed in the erythrocytes of the genetic model, the Nile tilapia (Oreochromis niloticus) exposed to water samples from the two sources tested when compared to a control group indicating the presence of genotoxic and hazardous pollutants in the water bodies of Estero de Paco and Estero de Vitas. Further, the water samples from Estero de Vitas were found to be far more genotoxic as compared to the water samples from Estero de Paco (p<0.05). The observed genotoxic effects of the water samples appeared to be related to the physico-chemical characteristics studied using atomic absorption spectroscopy, which showed the presence of heavy metals in the water samples from both the sources. The AAS results also confirm the presence of heavy metals in the fish tissue exposed to the water samples from the two locations. Hence, the tilapia fish (a component of Filipino diet) should be consumed with precautions as it can absorb the heavy metals present in ecosystems. The results establish that the fish micronucleus test is an effective assay for environmental biomonitoring. The lower genotoxicity potential of Estero de Paco clearly demonstrates that the restoration of the Esteros can be an effective approach to control pollution of the water bodies, especially the Pasig river system.
显示更多 [+] 显示较少 [-]Simultaneous Reduction of Smoke and NO Emission Using Lower Order Alcohols in a Jatropha Methyl Ester Fuelled Compression Ignition Engine
2019
Venkatesan Rajasekar, Varuvel Edwin Geo, Leenus Jesu Martin and Beddhannan Nagalingam
The objective of this work is to experimentally study the consequence of blending lower order alcohol (methanol and ethanol) with jatropha oil methyl ester (JOME) in a single cylinder, four stroke and watercooled CI engine. 70% JOME blended with 30% methanol (J70M30) and 70% JOME blended with 30% ethanol (J70E30) are the two blends prepared to operate the engine. Experiments were conducted from 0 to 100% load at a fixed engine speed of 1500 rpm and the results were compared with base fuels. Due to the inferior physical properties of JOME, brake thermal efficiency (BTE) decreases compared to diesel at maximum load. Also, NO emissions increased by 4% and smoke opacity decreases by 10% while operating the engine with JOME compared to diesel. Simultaneous reduction of NO and smoke is achieved by blending lower order alcohol with JOME and a slight improvement in BTE is observed.
显示更多 [+] 显示较少 [-]Antibiotic Resistance of Pseudomonas aeruginosa in Well Waters in Irrigated Zone (Middle Atlas-Morocco)
2019
Fatima Zahra Hafiane, Latifa Tahri, Najia Ameur, Rajaa Rochdi, Karim Arifi and Mohammed Fekhaui
Pseudomonas aeruginosa is a bacteria which can live in freshwater, soil and plants. It is a commensal of the digestive tube, slightly abundant in human body. Its presence in wells water is a result of current anthropogenic activity and pollution loads. It is an important nosocomial pathogenic agent characterized by an intrinsic resistance to multiple antimicrobial agents which can develop high-level multidrug resistance. To assess the contamination of these well waters by this pathogenic germ, two hundred samples were collected for four seasonal campaigns between March 2017 and May 2018 with a rate of forty three (43) samples per season in an irrigated zone. The samples were analysed to identify P. aeruginosa, then the isolated serotypes were determined by slid agglutination test using four pools and 20 monovalent Antisera. The detected P. aeruginosa were tested for susceptibility to 18 antibiotics. A total of (n=85/139) isolated strains were identified as P. aeruginosa representing 61.15 % of prevalence among Pseudomonas spp. Antimicrobial resistance revealed that 68% of them are multidrug resistant, while15.09 % of strains resist at least to 7 antibiotics, 30.19% resist at least to 11 antibiotics, 13.21% resist at least to 12 antibiotics, 5.66% resist at least to 13 antibiotics, and 3.77% resist at least to 14 antibiotics. The high level resistance of P. aeruginosa is observed with piperacillin tazobactam (100/10μg) (84.91%), ciprofloxacin (5μg) (79.25%), imipenem (10μg) and ceftazidime (30μg) (37.58%). The resistance of phenotypes of P. aeruginosa strains allowed to identify (n=20/85) ESBL, (n=31/85) oxacillinase broad spectrum ES-OXA, (n=5/85) phenotype of impermeability to imipenem, (n=12/85) cephalosporinase AMPC, and (n=17/85) wild type. The results showed the high antibiotic resistance levels of P. aeruginosa strains from well water samples against antibiotics. Furthermore, based on the results, these well waters can be a source of P. aeruginosa and human and animal susceptibility to other opportunistic pathogens.
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