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111.
Environmental Science and Pollution Research - During the past 10 years, exploiting engineered nanoparticles in agricultural sector has been rapidly increased. Nanoparticles are used to...  相似文献   
112.
This study reports on the determination of trace element (TE)—Li, As, Co, Cs, Cu, Pb, U, and Zn—and major element (ME)—Si, Al, Fe, Mg, Ca, Mn, Na, and K—concentrations in 18 riverbed sediments and a sediment core from the Var River catchment using inductively coupled plasma mass spectrometry (ICP-MS). The results were compared with those of a reference sediment core, and the contribution of clay and organic carbon contents in the distribution of TE and ME in the sediment samples was investigated. The mean concentrations of the ME were comparable in both core and riverbed samples and were within the natural averages. In the case of TE, the concentrations were lower in riverbed sediment samples than those found in the sediment core. High mean concentration of As was observed (7.6 μg g?1) in both core and riverbed sediments, relatively higher than the worldwide reported values. The obtained data indicated that the natural high level of arsenic might be originated from the parent rocks, especially metamorphic rocks surrounding granites and from Permian sediments. Statistical approach, viz., Pearson correlation matrix, was applied to better understand the correlation among TE in both riverbed and sediment core samples. No significant metallic contamination was detected in the low Var valley despite of the localization of several industrial facilities. Therefore, results confirm that the concentrations of the TE obtained in the riverbed sediments could be considered as a baseline guide for future pollution monitoring program.  相似文献   
113.
Summer heat in coastal subtropical Jeddah, augmented by heat from operating ground servicing equipment in King Abdul-Aziz International Airport (KAAIA), presents a major occupational problem to ground service operators, particularly the air traffic control coordinator (ATCC), that hinders their work efficiency and induces health disorders to them. The present study was conducted to assess the magnitude of this problem and propose heat control strategy and remedial actions for the Saudi Arabian Airlines (SAUDIA). Heat parameters including air temperature (T (a)), wet bulb temperature (T (w)), globe temperature (T (g)) and air velocity were measured around serviced planes and in other locations used by ATCC, and the WBGT and the ATCC-WBGT-TWAs were computed. Mostly all the T (a) measurements, and many T (w) measurements, were higher than T (a) and T (w) forecasted by the Presidency of Meteorology and Environment (PME) due to heat dissipated from operating vehicles and equipment in service. The measured and PME forecasted parameters have good and medium linear correlations (T (a): r (2) = 0.74 and T (w): r (2) = 0.64). The computed WBGT in the service stations around planes are considerably higher than the 25 and 27.5 degrees C recommended TLV(R) for non-acclimatized and acclimatized operators. However, the computed ATCC- WBGT-TWA levels indicate that the shift-work-schedule which was recommended to be implemented by SAUDIA has successfully reduced their heat exposure to acceptable levels, except for a very few operators (6.7% exceeding WBGT-TLV(R) of 25 degrees C and 2.2% exceeding TLV(R) of 27.5 degrees C) for whom the shift-work schedules might be corrected to achieve safe heat exposure.  相似文献   
114.
Environmental Chemistry Letters - The removal of toxic dyes from the wastewater and industrial effluents is a major environmental challenge. Various techniques have been employed for the removal of...  相似文献   
115.
ABSTRACT

The aim of this article is to analyse the performance of the Photovoltaic (PV) and to study the effect of soiling on the energy generation under Muscat environmental conditions. The generated energy is consumed in the eco-house, and the access energy is fed back to the electric grid. Two-ways metre was used to record the energy taken from the grid or fed back to the grid. The system was monitored from December 2014 until today. Various performance parameters of the plant were evaluated which include system efficiency, performance ratio (PR), capacity factor (CF) and different types of PV system losses and yields. The annual average values of recorded ambient temperature and solar radiation were 32°C and 482 W/m2, respectively.

The total annual energy produced was 23,595 kWh, whereas the annual average daily reference yield, array yield and final yield were 5.59, 3.78 and 3.64 kWh/kWP/day, respectively. The annual average daily PR and CF were 0.67 and 0.15, respectively, while the annual average system efficiency was 10.3%. Furthermore, the annual average daily capture, system and cell temperature losses were 1.82, 0.14 and 2.95 h/day,respectively, with a small reduction in energy production when modules left uncleaned.  相似文献   
116.
Journal of Material Cycles and Waste Management - Edible mushroom are grown commercially using lignocellulosic waste by applying a biological process. However after the harvesting season about 70%...  相似文献   
117.
A disaster such as floods can have a drastic impact on interdependent infrastructure and economic sectors. The resilience or the ability of the critical sector to recover quickly from the disruption can also reduce the consequences of the disaster. In this paper, through resilience and recovery time Dynamic Inoperability Input-Output model (DIIM) is applied. Thus, Input-Output (I-O) table is constructed for Pakistan's economic system and a case study is performed on the flooding in Pakistan 2011–12. The purpose of this study is to provide a ballpark estimate of the system-wide impact and ripple effect on the sectors that lasted for several days after the disruption. Furthermore, to analyze the inoperability and economic loss in the sectors caused by the disaster in a developing country. The findings of the research show that most of the critical sectors are associated with agriculture and service sector in terms of inoperability and economic loss respectively. The outcome of the study will be essential for the policy makers, disaster management authorities and health departments to respond accordingly.  相似文献   
118.
The central objective of this project was to utilize geographical information systems and remote sensing to compare soil erosion models, including Modified Pacific South-west Inter Agency Committee (MPSIAC), Erosion Potential Method (EPM), and Revised Universal Soil Loss Equation (RUSLE), and to determine their applicability for arid regions such as Kuwait. The northern portion of Umm Nigga, containing both coastal and desert ecosystems, falls within the boundaries of the de-militarized zone (DMZ) adjacent to Iraq and has been fenced off to restrict public access since 1994. Results showed that the MPSIAC and EPM models were similar in spatial distribution of erosion, though the MPSIAC had a more realistic spatial distribution of erosion and presented finer level details. The RUSLE presented unrealistic results. We then predicted the amount of soil loss between coastal and desert areas and fenced and unfenced sites for each model. In the MPSIAC and EPM models, soil loss was different between fenced and unfenced sites at the desert areas, which was higher at the unfenced due to the low vegetation cover. The overall results implied that vegetation cover played an important role in reducing soil erosion and that fencing is much more important in the desert ecosystems to protect against human activities such as overgrazing. We conclude that the MPSIAC model is best for predicting soil erosion for arid regions such as Kuwait. We also recommend the integration of field-based experiments with lab-based spatial analysis and modeling in future research.  相似文献   
119.
The purpose of this study is to assess potential radiological impacts of utilizing pulverized fly ash (PFA) as a constituent in ordinary Portland cement. For this purpose, the activity concentrations of 226Ra, 232Th, and 40K in samples of PFA and Portland cement containing 15%, 20%, and 25% by mass PFA were measured using gamma-ray spectrometry with HPGe detector. The mean activity concentrations of 226Ra, 232Th, and 40K were found as 366.6, 113.7, and 460.2 Bq kg???1, 94.2, 25.9, and 215.3 Bq kg???1, 113.7, 34.3, and 238.3 Bq kg???1, and 124.2, 41.8, and 279.3 Bq kg???1 for the examined samples of PFA, Portland cement with 15%, 20%, and 25% by mass PFA, respectively. Radiological parameters such as radium equivalent activity, external exposure index (activity concentration index), internal dose index (alpha index), indoor absorbed gamma dose rate, and the corresponding the annually effective dose were assessed for Portland cement samples containing three percentages (15%, 20%, and 25%) by mass PFA. The results of assessment show that all Portland cement samples are within the safe limits recommended for building materials for dwellings.  相似文献   
120.
This paper presents an understanding of groundwater salinity by identification of effective factors using chemometric methods (cluster analysis and multiple linear regressions) in Manukan Island, Sabah. Local groundwater and environmental properties were used to explore the effective factors of groundwater salinity. Cluster analysis showed salinity and chloride illustrated the highest similarities. Electrical conductivity and total dissolved solids were also grouped in the same cluster. Seawater is the only chloride source in groundwater of Manukan Island demonstrated an indication of seawater mixing in freshwater. It is an effect of upward movement of the seawater by pumping activities. Precipitation and evapotranspiration (environmental condition) with hydraulic heads were clustered together to show that they also influence salinity concentration in groundwater. Multiple linear regressions showed descending order of the factors from chloride (the largest contribution) to evapotranspiration (the smallest contribution) and illustrated the contribution to groundwater salinity in Manukan Island. The integrated results using chemometric methods have provided a way to identify the effective factors on groundwater salinity. This similar approach and resulting equation can be applied in other small tropical islands with alike hydrogeological condition and limited information available for a better understanding of its groundwater salinity.  相似文献   
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