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81.
Ankit Tandon Sudesh Yadav Arun K. Attri 《Atmospheric environment (Oxford, England : 1994)》2010,44(9):1237-1243
The coarser (CPM) and respirable (RPM) fractions of aerosol loads collected in a time sequence, during the onset of winter season in Delhi region, were subjected to Principal Component Analysis (15 elemental variables, 39 samples); the absolute mass contributed by each identified source to the CPM and RPM was quantified by using Absolute Principal Component Score (APCS) and Positive Matrix Factorization (PMF) method. Interestingly, the mass contributed by the local crustal source (material) to both fractions manifested undulating periodic behavior, a dominating harmonic corresponding to 24-h period was detected by using Discrete Fourier Transform (DFT). The corresponding harmonics, of varying strengths, were also detected in the recorded meteorological factors: Planetary Boundary Layer (PBL), Surface Level Temperature (T), Surface Level Relative Humidity (RH) and Wind Speed (WS). The analysis of the respective harmonic strength within the CPM, RPM, and meteorological factors suggested that the undulation observed in both size fractions of aerosol load from the local crust was affected by the meteorological factors. The large proportion of undulating loads (CPM and RPM), explained by the dominating harmonic, was fully accounted for by the empirical relation involving the discrete coupling parameters, and the recorded meteorological factors: PBL, T, RH and WS. The analysis suggests that the magnitude and the direction (‘positive’ load increase and ‘negative’ the reverse) of coupled meteorological factors'(s) effect on ambient CPM, RPM load is determined by the phase difference between the harmonic explaining the aerosol fraction's load and the corresponding harmonic present in the respective meteorological factor. The absolute mass contributions arising from the identified sources (APCS and PMF) allowed us to calculate the baseline ambient concentrations of undulating CPM and RPM loads, in the region of this study, affected by meteorological factors only. 相似文献
82.
Textile mill waste can be vermicomposted if it is mixed in the range of 20–30% with cow dung. This article reports the effect
of inoculation, of nitrogen fixing Azotobacter chroococcum strain; Azospirillum brasilense strain and phosphate solubilizing Pseudomonas maltophila, on nitrogen and phosphorus content of vermicomposts prepared from cow dung (CD) and cow dung spiked textile mill sludge
(CD + STMS). The CD vermicompost was more supportive to the growth and multiplication of all the three bacteria than CD + STMS
vermicompost. In Azotobacter chroococcum treated vermicomposts maximum nitrogen content was recorded between 45 and 60 days [CD␣vermicompost (25.9 ± 0.45 g kg−1) and CD + STMS vermicompost (20.6 ± 0.62 g kg−1)] followed by Azospirillum brasilense inoculation [CD vermicompost (19.4 ± 0.60 g kg−1) and CD + STMS vermicompost (18.6 ± 0.17 g kg−1)]. Phosphorus content in Pseudomonas maltophila inoculated CD vermicompost was 20.8 ± 0.20 g kg−1 and CD + STMS vermicompost was 13.4 ± 0.45 g kg−1 after 75th day of inoculation. 相似文献
83.
Effects of BHC (8 mg litre(-1)) and malathion (10 mg litre(-1)) exposure for 96 h have been studied on T(3) and T(4) concentrations in plasma, and in pharyngeal thyroid tissue preparations. Thyroid peroxidase (TPO) activity in the pharyngeal thyroid tissue, along with the extra-thyroidal conversion of T(4) into T(3) were measured in a freshwater catfish, Heteropneustes fossilis. BHC stimulated TPO activity in this fish, during both in vitro and in vivo studies. In contrast, malathion was found to stimulate TPO activity during the in vitro experiments but to inhibit it in the in vivo study. Concentrations of T(3) and T(4) increased in the thyroid gland, as well as in the plasma, in response to BHC exposure. However, in both these tissues, malathion increased T(3) concentrations and reduced T(4) concentrations. The extrathyroidal conversion of T(4) into T(3) was stimulated by malathion and inhibited by BHC. 相似文献
84.
Yadav Deepak Kumar Chawla Kanhaiya Jain I. P. Lal Chhagan 《Environmental science and pollution research international》2021,28(4):3866-3871
Environmental Science and Pollution Research - Reversible hydrogen storage in MgH2 under specified conditions is a possible way for the positive reception of hydrogen economy, in which the... 相似文献
85.
Tracing the geographic origin of traded leopard body parts in the indian subcontinent with DNA‐based assignment tests 下载免费PDF全文
Samrat Mondol Vanjulavalli Sridhar Prasanjeet Yadav Sanjay Gubbi Uma Ramakrishnan 《Conservation biology》2015,29(2):556-564
Illicit trade in wildlife products is rapidly decimating many species across the globe. Such trade is often underestimated for wide‐ranging species until it is too late for the survival of their remaining populations. Policing this trade could be vastly improved if one could reliably determine geographic origins of illegal wildlife products and identify areas where greater enforcement is needed. Using DNA‐based assignment tests (i.e., samples are assigned to geographic locations), we addressed these factors for leopards (Panthera pardus) on the Indian subcontinent. We created geography‐specific allele frequencies from a genetic reference database of 173 leopards across India to infer geographic origins of DNA samples from 40 seized leopard skins. Sensitivity analyses of samples of known geographic origins and assignments of seized skins demonstrated robust assignments for Indian leopards. We found that confiscated pelts seized in small numbers were not necessarily from local leopards. The geographic footprint of large seizures appeared to be bigger than the cumulative footprint of several smaller seizures, indicating widespread leopard poaching across the subcontinent. Our seized samples had male‐biased sex ratios, especially the large seizures. From multiple seized sample assignments, we identified central India as a poaching hotspot for leopards. The techniques we applied can be used to identify origins of seized illegal wildlife products and trade routes at the subcontinent scale and beyond. 相似文献
86.
Yadav S Irfan M Ahmad A Hayat S 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(5):667-685
Salinity in agricultutal terms is the excess of salts above the level plant require. Most often it poses constrains in the growth hence productivity of the category of plants called glycophytes, wherein falls major crops, therefore is a serious concern. It is often recognized as excess of sodium ions (sodicity) that imparts life threatening consequences in plant due to mal-textured soil hindered porosity and aeration leads to physiological water deficit. Mingling with other edaphic/environmental factors viz. precipitation, temperature, flooding, soil profile, water table exaggerates the catastrophe synergistically. Improper irrigations system, leaching fraction added with land clearing and deforestation have been marked as the major cause. The present review underlines the different sources of salinity stress and their physiological manifestations, toxicity responses alongwith tolerance in plants and management strategies in affected landscapes. 相似文献
87.
Survey of nitrogen use pattern in rice in the irrigated rice-wheat cropping system of Haryana, India
Singh S Malik RK Dhankar JS Garg R Sheoran P Yadav A Kamboj BR 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(1):43-49
Seeing the sustainability of rice-wheat cropping system (RWCS) of the Indo-Gangetic Plain, adequate crop nutrition in general and nitrogen (N) in particular holds the key to sound crop management. The excessive application or insufficient management of N means an economic loss to the farmer and may lead to yield penalties and environmental problems. Improving N management in consonance with other nutrients is much important to break yield plateaus as breeding for high yielding is not happening in recent years. Findings from farm survey are used to evaluate the on-farm N management practices in rice crop of the study area. The crop management practices (especially time of sowing/transplanting and irrigation requirement) and resource base of the farmers decided the N use pattern of the farmers. The N(Physical optimum) and N(economic optimum) exceeding the recommended levels revealed the apparent need for the revalidation of the existing recommendations. Paddy yield increased significantly within different rice types. This study generated comprehensive data on N use pattern in rice in the study area. 相似文献
88.
Yadav Monika Thakore Sonal Jadeja Rajendrasinh 《Environmental science and pollution research international》2022,29(1):236-250
Environmental Science and Pollution Research - Modern lifestyle and alleviated anthropogenic activities have increased the pollutant load, ultimately causing stress on the environment. In... 相似文献
89.
Abhishek Dutt Tripathi Ajay Yadav Alok Jha S. K. Srivastava 《Journal of Polymers and the Environment》2012,20(2):446-453
In the present study, depending upon the availability and cheaper cost, different carbon source were tested for the production of PHAs (Polyhydroxyalkonoates) by soil bacterium Pseudomonas aeruginosa and it was found that sugar refinery waste (cane molasses) produced the maximum PHA (biodegradable polymer) which is precursor for bio-plastic development. Urea served as potent nitrogen source over other inorganic nitrogen sources in bio-plastic synthesis. Effect of different physical parameters viz; pH, temperature and agitation speed were also studied on PHA production. Batch cultivation kinetics under optimized cultural and physical condition showed maximum cell mass and PHA concentration of 7.32?±?0.2 and 5.60?±?0.3?g/L, respectively after 54.0?h of cultivation. Sugar refinery waste (Total sugar 4%) and urea (0.8%) improved the economics of the process which exhibited a yield (YP/X) of 0.70 with productivity of 0.11?g/L/h. PHA was further characterized as PHB by using Fourier Transform Infra-red Spectroscopy (FT-IR). 相似文献
90.
Sandeep Yadav Varsha Srivastava Sushmita Banerjee Fethiye Gode Yogesh C. Sharma 《Environmental science and pollution research international》2013,20(1):558-567
This paper highlights the utility of riverbed sand (RS) for the treatment of Ni(II) from aqueous solutions. For enhancement of removal efficiency, RS was modified by simple methods. Raw and modified sands were characterized by scanning electron microscope (SEM), Energy Dispersive Spectroscopy (EDS), and Fourier Transform Infrared Spectroscopy (FTIR) to investigate the effect of modifying the surface of RS. For optimization of various important process parameters, batch mode experiments were conducted by choosing specific parameters such as pH (4.0–8.0), adsorbent dose (1.0–2.0 g), and metal ion concentrations (5–15 mg/L). Removal efficiency decreased from 68.76 to 54.09 % by increasing the concentration of Ni(II) in solution from 5 to 15 mg/L. Removal was found to be highly dependent on pH of aqueous solutions and maximum removal was achieved at pH 8.0. The process of removal follows first-order kinetics, and the value of rate constant was found to be 0.048 min?1 at 5 mg/L and 25 °C. Value of intraparticle diffusion rate constant (k id) was found to be 0.021 mg/g min1/2 at 25 °C. Removal of Ni(II) decreased by increasing temperature which confirms exothermic nature of this system. For equilibrium studies, adsorption data was analyzed by Freundlich and Langmuir models. Thermodynamic studies for the present process were performed by determining the values of ΔG°, ΔH°, and ΔS°. Negative value of ?H° further confirms the exothermic nature of the removal process. The results of the present investigation indicate that modified riverbed sand (MRS) has high potential for the removal of Ni(II) from aqueous solutions, and resultant data can serve as baseline data for designing treatment plants at industrial scale. 相似文献