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Detection of Metallothionein Protein Biomarkers (MTs) and Pinocytosis Activity in Gambusia Fish (Gambusia affinis) Exposed to Cadmium 全文
2019
Moh. Awaludin Adam, Maftuch, Yuni Kilawati and Yenny Risjani
This study aims at detecting the metallothionein protein that binds cadmium in Gambusia fish using MT ELISA kit and Western Blotting testing. The continuation of the detection is used as a basis for analysing the macrophage and pinocytosis activity on Gambusia fish exposed to cadmium. The methods used to detect metallothionein protein are the MT ELISA kit and Western Blotting test. Meanwhile, to check the fish immunity, macrophage cells and pinocytosis activity were tested. The results indicated that the total proteins detected by the method of MT ELISA kits showed an increasing number with concentrations of exposure to Cd good at acute doses and sub-chronic higher doses (treatment A: 0.066 ± 0.019 ng/mL; B: 0.053 ± 0.022 ng/mL; C: 0,045 ± 0,014 ng/mL; D : 0,021 ± 0,012 ng/mL; E : 0,032 ± 0,019 ng/mL; and control k : 0,018 ± 0,018 ng/mL). Similarly, in the pinocytosis activity, the number of macrophage cells between treatment and control was significantly different (Cd ³ 3x106 treatment; Cd ³ 1x106 no treatment) and the number of pinocytosis activity was significantly different (Cd ³ 24 PA treatment; Cd ³ 10 no PA treatment). Increasing pollutants from cadmium exposure affect the fish health. Pollution causes changes in macrophage’s immune cells and phagocytosis Gambusia affinis, which can change the overall innate immunity system and fish health. The change of immune cells associated with the species and biological conditions is not present. Analysis of the number of immune cells revealed that Gambusia has decreased its macrophage pinocytosis activity, thereby indicating that phagocyte activity is a sensitive biomarker and a good bio-indicator for cadmium pollution.
显示更多 [+] 显示较少 [-]Effects of Flax Straw Biochar on Soil Properties, Fractions and Maize Availability of Lead and Cadmium in Light Sierozem 全文
2019
Baowei Zhao, Renzhi Xu, Fengfeng Ma, Yewei Li and Lu Wang
Bioavailability of heavy metals can be reduced in acidic soils with biochar amendment but the situation in alkaline soils is not much clear. Effects of four rates (1%, 5%, 10% and 15% w/w) of flax (Linum usitatissimum L.) straw biochar (FBC) prepared at 600oC on the properties of soil, fraction and phytoavailability of Pb and Cd, and plant growth in the simulated Pb (1000 mg.kg-1) or Cd (20 mg.kg-1) contaminated light sierozem were assessed with pot experiments using maize (Zea mays L.) as an indicator plant. The amendment of FBC significantly enhanced the pH value, cationic exchange capacity (CEC) and organic matter of soil (P < 0.05). The BCR sequential extraction results indicated that the acid extractable fraction of Pb or Cd only decreased by 12.80% or 5.56% when FBC was added with the high rate of 15%. The uptake of Pb or Cd by maize shoots scarcely decreased with 1% and 5% of FBC amendment. Significant inhibitory effects of FBC on the growth of maize shoots were observed with FBC amendment at the rates of 10% and 15%. The results could provide a different implication for immobilization remediation of loess soils (e.g., light sierozem) contaminated with heavy metals.
显示更多 [+] 显示较少 [-]3D Simulation Model of Tidal, Internal Mixing and Turbulent Kinetic Energy of Palu Bay 全文
2019
Sabhan, Alan Frendy Koropitan, Mulia Purba and Widodo Setiyo Pranowo
The tidal simulation models and internal mixing were constructed using finite volume method to simulate diurnal tide (K1) constituent and semidiurnal tide (M2) constituent, the mixing level model using General Ocean Turbulence Model (GOTM). Tidal elevation amplitude of the model K1 ranges from 19.27 to 19.31 cm, high tidal amplitude at the point near the mouth of the Palu River, low tidal amplitude at the open boundary of the model that leads to the Makassar Strait. The amplitude range by M2 tidal constituents is 55.55-55.75 cm, high tidal amplitude at the mouth of Palu Bay and the end of Palu Bay and the slope area. The tidal current of the K1 constituent strengthens at the open boundary of the model and weakens into Palu Bay, which then undergoes strengthening near the mouth of the Palu River which experiences extreme siltation, tidal currents strengthen in the mouth area of Palu Bay and the tip of Palu Bay is caused by the tidal constituent propagation M2 and also the slope of the area along the coast of Palu Bay. Bottom Ekman layer which is caused by K1 constituent can reach 11 meters while the M2 constituent reaches 7 meters. In the slope area, are also found the buoyancy frequency with the order of 10-5 which is at a depth of 75-150 m. Kinetic energy in Palu Bay stands at O (10-5-10-3) with high kinetic energy around rough topography in the order of 10-3 around the mouth of Palu Bay.
显示更多 [+] 显示较少 [-]Synergetic Effects of Zero-valent Iron and Morganella morganii on the Removal of Cr(VI) from Wastewater 全文
2019
Jiamin Huang, Yizi Ye, Zheng Fu, Wen Jing Dun, Yangyang Wang, Linshan Fang, Suhui Ye, Xiaoying Ye, Jiaojun Jin and Qingyuan Hu
Zero-valent iron permeable reactive barrier (ZVI-PRB) has attracted great attention for its high efficiency and low cost in the in-site remediation process. However, passivating oxide layers are usually yielded and covered on the surface of ZVI, which shorten the service life of PRB. In this study, Morganella morganii subsp was used to hydrolyse the passivating oxide layers on ZVI. The hydrolysing condition was optimized. The highest Cr(VI) removal efficiency was achieved with glucose of 4 g/L, yeast powder of 6 g/L and pH = 7. With Morganella morganii subsp, the maximum removal quality of ZVI was increased from 19.96 mg/g to 24.35 mg/g, indicating Morganella morganii subsp could improve the reduction ability of ZVI. SEM-EDS analysis also showed that M. morganii subsp could promote the surface corrosion of ZVI and adsorb Cr simultaneously.
显示更多 [+] 显示较少 [-]Preparation, Characterization and Adsorption Capacity of Bauxite-Carbon Nanotube Composite 全文
2019
Suha Sahib Abd and Ahmed Mohammed Abbas
Iraqi bauxite clay was modified by using multiwall carbon nanotube (MWCNTs) as a modifying agent. The characterization of bauxite and bauxite/carbon nanotube was accomplished by using the Fourier transform infrared spectroscopy, scanning electron microscopy, atomic forces microscopy and X-Ray diffraction techniques. Uses the bauxite and bauxite/carbon nanotube composite for methyl green dye adsorption were achieved in a batch system. The adsorption equilibrium was attained at 60 and 45 min and adsorption efficiency reached maximum of 22 and 31% for bauxite and bauxite/carbon nanotube composite respectively, at an adsorbent dose of 0.01 g and initial dye concentration of 16 mg/L. Relying on the above shows that bauxite/carbon nanotube is a suitable adsorbent for the adsorption of methyl green dye, better than the bauxite clay.
显示更多 [+] 显示较少 [-]Urban and Rural Residents’ Willingness to Pay for Desertification Prevention and Control and its Influencing Factors 全文
2019
Weipeng Chao, Changjiang Zhang and Pengcheng Wang
The prevention and control of desertification cannot be separated from the active participation of local urban and rural residents. However, only a few studies on the difference in urban and rural residents’ willingness to pay for the prevention and control of desertification and its influencing factors are available. To explore the differences in urban and rural residents’ willingness to pay for desertification prevention and control, the status quo and influencing factors of willingness to pay for desertification prevention and control among urban and rural residents were analysed by linear regression analysis method and the micro-survey data of 300 urban and rural residents in the middle and lower reaches of the Tarim River in Xinjiang, China. Results show that urban and rural residents’ willingness to pay for desertification prevention and control is affected by education level, ecological environment concern, ecological environment protection needs, attention to desertification, and cognition of desertification control effect. Several preventive measures were provided with respect to enhancing residents’ awareness of desertification prevention and control, raising residents’ income and push forward systematic innovation.
显示更多 [+] 显示较少 [-]A Project Design for Air Pollution Studies Over Bobodioulasso-Burkina Faso 全文
2019
Emetere M.E., Sanni S.E. and Okoro E.E.
This paper introduces a project design on estimating air pollution over geographical regions that have a mono-source of data acquisition. Fourteen years (2000-2013) aerosol optical depth dataset was obtained from the Multi-angle Imaging Spectro-Radiometer (MISR). The peculiar design that has been discussed in this paper focusses on human health and environmental disturbances. The secondary datasets that were generated from the primary data were aerosol loading, particles sizes, Angstrom parameter, and the statistics of the primary dataset. A computational data treatment was introduced for the determination of data reliability of the dataset. The techniques highlighted in this study are germaine to be reproduced in several geographical locations.
显示更多 [+] 显示较少 [-]Vulnerability, well-being, and livelihood adaptation under changing environmental conditions: a case from mountainous region of Pakistan 全文
2019
Shahzad, Laila | Tahir, Arifa | Sharif, Faiza | Khan, Waqas Ud Din | Farooq, Muhammad Ansar | Abbas, Azhar | Saqib, Zulfiqar Ahmad
Climatic changes pose serious risks to the rural community’s livelihoods of many developing countries whereas people in mountainous regions are exposed to multiple hazards with limited livelihood resources and heavy dependence on natural resources. The objective of the current study is to assess the livelihood practices and adaptive capacity of a mountainous region of Pakistan, the Balakot, where people are highly vulnerable to climatic changes. The study uses a triangulation method to explore various issues and options of climate change risks sand adaptation and impact of well-being on resilience capacity and livelihood strategies. For this purpose, ten focus group discussions (FGDs) with carefully selected key informants and structured interviews with randomly selected 200 local households are conducted to evaluate different hazards and their associated livelihood effects. It is observed that the changing climate has significantly influenced livelihoods of the local community in the recent past through resource degradation, gradual unavailability of sufficient basic services (quantity and quality of drinking water, crop food diversity, fuel wood, and non-timber forest products), low agricultural productivity, and social inequity viz. income distribution, health, education, and food storage. Such a brunt is felt disproportionately more by poor households due to their low adaptive capacity to climate change with constrained livelihood resources. The study emphasizes the need for targeted efforts to move from coping strategies to adaptations among people considering their social inequalities. Timely information sharing, livelihood diversification and preservation of livelihood resources such as crop and forest production, livestock grazing, creating awareness on the pace, and pattern of climate change in the region and subsequent role of adaptation options are major interventions that should be emphasized by the public bodies.
显示更多 [+] 显示较少 [-]Effect of temperature on tertiary nitrogen removal from municipal wastewater in a PHBV/PLA-supported denitrification system 全文
2019
Xu, Zhongshuo | Dai, Xiaohu | Chai, Xiaoli
In this study, a poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/poly(lactic acid) (PHBV/PLA)–supported denitrification system was built to remove nitrogen from municipal wastewater treatment plant secondary effluent, and the influence of operating temperature on nitrogen removal was further investigated. Results indicated that a PHBV/PLA-supported denitrification system could effectively fulfill the tertiary nitrogen removal. The nitrogen removal efficiency gradually declined with the operating temperature decreasing, and the denitrification rate at 30 °C was 5 times higher than that at 10 °C. Meanwhile, it was found that a slight TOC accumulation only occurred at 30 °C (with an average of 2.03 mg/L) and was avoided at 10~20 °C. The reason for effluent TOC variation was further explained through the consumption and generation pathways of TOC in this system. Furthermore, the temperature coefficient was about 0.02919, indicating that the PHBV/PLA-supported denitrification system was a little sensitive to temperature. A better knowledge of the effect of operating temperature will be significant for the practical application of the solid-phase denitrification system.
显示更多 [+] 显示较少 [-]Dynamic simulation of the optimal allocation of water resources via the introduction of integrated water environmental policies in Baoding, China 全文
2019
Mou, Siyu | Yan, Jingjing | Sha, Jinghua | Li, Shule | Ma, Yufang | He, Gengyu | Song, Ci
With rapid industrialization and urbanization, regional water shortages and water quality deterioration have posed great challenges for the sustainable development of cities in North China, especially those with a large demand for agricultural irrigation water. Based on an input-output analysis, this paper develops a dynamic optimization model consisting of three sub-models and multiple constraint conditions to solve the water crisis of Baoding, a typical city experiencing water shortages and serious water pollution in North China. The water resource carrying capacity (WRCC) indicator is introduced in the analysis of the results to comprehensively assess the effect of integrated water environmental policies (IWEPs) from 2013 to 2025. In the optimal scenario, the annual chemical oxygen demand (COD) discharge and annual water demand in Baoding can be reduced by 2.6% and 0.6%, respectively, with an annual gross regional product (GRP) growth rate of 7.52%. The WRCC can be improved from moderately overloaded to weakly unsaturated, which indicates that water resources can meet the socioeconomic development requirements. The results demonstrate the effectiveness of the linear optimization model with input-output analysis in coordinating the relationships among water demand, water environment protection, and economic development, and the IWEPs provide an applicable reference for decision-makers in Baoding and other similar cities in North China to address deteriorating water systems.
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