排序方式: 共有54条查询结果,搜索用时 252 毫秒
21.
Antibiotics consumption has increased worldwide, and their residues are frequently reported in aquatic environments. It is believed that antibiotics reach aquatic water bodies through sewage. Medicine consumed for healthcare practices are often released into sewage, and after sewage treatment plant, it reaches the receiving water bodies of lakes or rivers. In the present study, we determined the fate of some commonly used antibiotics in a sewage treatment plant (STP) located in Delhi and the environmental concentration of these antibiotics in the Yamuna River, which receives the sewage and industrial effluent of Delhi. There are many reports on antibiotics occurrences in STP and river water worldwide, but monitoring data from the Indian subcontinent is sparse. Samples were taken from a STP and from six sampling sites on the Yamuna River. Several antibiotics were tested for using offline solid-phase extraction followed by high-performance liquid chromatography equipped with photodiode array analysis. Recoveries varied from 25.5–108.8 %. Ampicillin had the maximum concentration in wastewater influents (104.2?±?98.11 μg l?1) and effluents (12.68?±?8.38 μg l?1). The fluoroquinolones and cephalosporins had the lower concentrations. Treatment efficiencies varied between 55 and 99 %. Significant amounts of antibiotics were discharged in effluents and were detected in the receiving water body. The concentration of antibiotics in the Yamuna River varied from not detected to 13.75 μg l?1 (ampicillin) for the compounds investigated. 相似文献
22.
H. Daraei A. Mittal M. Noorisepehr F. Daraei 《Environmental science and pollution research international》2013,20(7):4603-4611
The aim of the present research is to develop economic, fast, and versatile method for the removal of toxic organic pollutant phenol from wastewater using eggshell. The batch experiments are conducted to evaluate the effect of pH, phenol concentration, dosage of adsorbent, and contact time on the removal of phenol. The paper includes in-depth kinetic studies of the ongoing adsorption process. Attempts have also been made to verify Langmuir and Freundlich adsorption isotherms. The morphology and characteristics of eggshell have also been studied using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and X-ray fluorescence analysis. At ambient temperature, the maximum adsorption of phenol onto eggshells has been achieved at pH 9 and the contact time, 90 min. The experimental data give best-fitted straight lines for pseudo-first-order as well as pseudo-second-order kinetic models. Furthermore, the adsorption process verifies Freundlich and Langmuir adsorption isotherms, and on the basis of mathematical expressions of these models, various necessary adsorption constants have been calculated. Using adsorption data, various thermodynamic parameters like change in enthalpy (?H 0), change in entropy (?S 0), and change in free energy ?G 0 have also been evaluated. Results clearly reveal that the solid waste material eggshell acts as an effective adsorbent for the removal of phenol from aqueous solutions. 相似文献
23.
24.
Alok Mittal 《毒物与环境化学》2013,95(10):1813-1823
Bottom ash and de-oiled soya have been evaluated as potential adsorbents for the removal of a water soluble azo dye. The characterization of the adsorbents has been performed using infrared spectroscopy and differential thermal analysis. A batch of adsorption method has been adopted for studying the effects of pH, adsorbate concentration, and particle size on the adsorption process. The experimental data were tested using Langmuir, Freundlich, Tempkin, and Dubinin–Radushkevich isotherms and their parameter constants were determined. The thermodynamics showed that the process is spontaneous and exothermic. The kinetic studies revealed that the adsorption process follows first-order kinetics. A fixed-bed adsorption experiment resulted in 89% and 94% saturation of bottom ash and de-oiled soya, respectively, indicating that both adsorbents can be potentially economical. 相似文献
25.
Harilal Manu George R. P. Philip John Albert Shaju K. 《Environmental science and pollution research international》2021,28(22):28107-28132
Environmental Science and Pollution Research - This study reports the enhanced chemical resistance of a blended concrete mix (CFNI) made with 40 wt.% fly ash, 2 wt.% nanoparticles, and 2 wt.%... 相似文献
26.
In the pursuit of Health and Safety (H&S) improvement within the UK construction industry, several studies have been conducted to identify accident causal factors to enable the development of accident prevention measures. Adding to such studies, a critique of H&S literature demonstrates that construction project features (CPFs) such as the nature of project, method of construction, site restriction, project duration, procurement system, design complexity, level of construction, and subcontracting contribute to accident causation and that their contribution is through the introduction of proximal accident causal factors into the construction process. However, the extent of this contribution by these CPFs remains sparingly known and requires further investigation. The study provides this insight by indicating that the extent to which CPFs contribute to accident causation is influenced by two factors; the extent to which the proximal factors contribute to accident causation; and the extent to which the proximal factors are prevalent within the CPFs. In line with this fresh insight, an approach for determining the extent to which CPFs contribute to accident causation is put forth. The approach proposes to use a qualitative–quantitative rating scale to determine the two determinant factors and then combine them using a mathematical formula to obtain the extent to which CPFs contribute to accident causation. By this approach the grey areas in literature concerning the extent to which CPFs contribute to accident causation will be illuminated and by that contribute to improvement in construction accident prevention. 相似文献
27.
Ecological interactions between crops and wild animals frequently result in increases or declines in crop yield. Yet, positive and negative interactions have mostly been treated independently, owing partly to disciplinary silos in ecological and agricultural sciences. We advocate a new integrated research paradigm that explicitly recognizes cost-benefit trade-offs among animal activities and acknowledges that these activities occur within social-ecological contexts. Support for this paradigm is presented in an evidence-based conceptual model structured around five evidence statements highlighting emerging trends applicable to sustainable agriculture. The full range of benefits and costs associated with animal activities in agroecosystems cannot be quantified by focusing on single species groups, crops, or systems. Management of productive agroecosystems should sustain cycles of ecological interactions between crops and wild animals, not isolate these cycles from the system. Advancing this paradigm will therefore require integrated studies that determine net returns of animal activity in agroecosystems.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0696-y) contains supplementary material, which is available to authorized users. 相似文献28.
Daraei Hasti Mittal Alok Toolabian Kimia Mittal Jyoti Mariyam Asna 《Environmental science and pollution research international》2023,30(9):22273-22283
Environmental Science and Pollution Research - 2,4-Dinitrophenol (2,4-DNP) is a toxic compound that is widely used in many industrial and agricultural processes. This compound has low... 相似文献
29.
Environmental Fluid Mechanics - Pedestrian level wind comfort, natural ventilation and pollutant dispersion are strongly influenced by building shape and orientation. In the recent years, the trend... 相似文献
30.
Vuggili Sai Bhargava Kadiya Kaushal Gaur Umesh Kumar Sharma Manu 《Environmental science and pollution research international》2021,28(34):46377-46389
Environmental Science and Pollution Research - The synthesis of graphitic carbon nitride/cadmium sulfide core-shell nanofibers has been studied for the improved photodegradation of methylene blue... 相似文献