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141.
A reliable wastewater characterization is a prerequisite for the selection of an acceptable treatment strategy for produced water which exhibits significant differences due to the varied kinds of wells, seasonal changes, and formation types. A complete characterization of produced water generated from oil, gas, and oil–gas fields in Turkey was performed based on seasonal and locational variations. The results showed that the produced water generated from oil field wells was highly polluted and wastewater volume was higher in comparison to gas and oil–gas field wells. Besides, the characterization of produced water was varying in a wide range based on seasonal and locational variations. Useful relationships were observed between chloride, sodium, bromide, and total dissolved solids concentrations. The results can be used in the design, operation, and optimization of wastewater treatment systems of petroleum and oil industries for future studies.  相似文献   
142.
The power generation potential of a microbial fuel cell (MFC) during the process of benzene biodegradation with potassium ferricyanide (0–200 mM) as the terminal electron acceptor was evaluated. Experimental results demonstrate that benzene was used as the sole carbon source in generating electricity by a mixed culture. The power density increased from 0.0276 to 2.1 mW m?2 as the concentration of potassium ferricyanide in the cathode chamber was increased from 0 to 200 mM. With a benzene concentration of 10.87 mg L?1 and a potassium ferricyanide concentration of between 0 and 150 mM, complete degradation of benzene was achieved in 22–24.5 h. However, when the concentration of potassium ferricyanide was raised to 200 mM, the time required for complete benzene degradation was prolonged to 35 h. The results of this investigation can be used as a basis for future assessments of the power generation capacity of MFCs that are used to treat benzene‐contaminated wastewater.  相似文献   
143.
Due to the unique chemical properties and therefore wide range of applications, significant amounts of reactive dyes often end up in waste waters and this issue raises the need for more efficient treatment technologies. This work investigates the ability of magnetite nanoparticles functionalized with imidazolium based ionic liquid (IL) as an efficient sorbent for the removal of the Reactive black 5 from wastewater. Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, thermo‐gravimetric analysis, and zeta potential measurement were used to characterize the synthesized nanosorbent. The results showed that under optimal conditions, the dye removal efficiency of the grafted IL is 98.5% after a single run. Regeneration of the used sorbent could be possible and the modified magnetic nanoparticles exhibited good reusability. The isothermal data of RB5 sorption conformed well to the Langmuir model and the maximum sorption capacity of IL@Fe3O4 for RB5 was 161.29 mg g?1. Thermodynamic study indicated that the adsorption is endothermic and spontaneous. The use of such a system can provide fast and efficient removal of the reactive dyes from wastewater by using an external magnetic field.  相似文献   
144.
通过测定土柱和淋洗液中重金属的含量,研究石灰岩质土壤应用粉煤灰污泥添加剂改良后重金属在土壤剖面上的分布移动特征及对地下水质的影响.结果表明:仅试验层内除As和Ni外,Zn、Cd、Pb、Cu、Cr、Hg含量明显增加,未出现明显向下移动的趋势;同时重金属淋出量明显增加,但未超过地下水Ⅲ级标准.初步认为与添加剂自身、重金属的特性及石灰岩质土壤滤层的截固作用相关.粉煤灰污泥经过合理的配施和预处理应用于石灰岩质矿区退化土壤的改良,短期内不会对地下水的质量产生明显的影响.  相似文献   
145.
Nano‐alumina modified by 9‐aminoacridine was used as a sorbent for separation and determination of dichromate ions from water. Statistical method, based on surface response design, has been used for the optimization of dichromate ions elution from 9‐aminoacridine nano‐alumina. The adsorbed dichromate ions were found to be eluted quantitatively with 0.8 mol L?1 KCl in 1.6 mol L?1 NaOH which optimized by response surface design. Under optimum conditions, the accuracy, precision (relative standard deviation, RSD%) and R‐square of the method were calculated as >98, <3, and >94%, respectively. Remarkable agreement between experimental and theoretical data was confirmed the predicted assumption. The method was applied to the simultaneous determination of dichromate in natural and industrial water samples. We also examined the retention of dichromate anions in the presence of Cl?, , and anions at pH 3.  相似文献   
146.
The electrochemical oxidation (EO) of diethyl phthalate (DEP) in aqueous solution was studied at Pb/PbO2 and Ti/SnO2 anode materials under galvanostatic‐experimental conditions. Results obtained clearly demonstrated that the anode plays a significant role for the optimization of the oxidation process, deciding the mechanisms and by‐products formed. DEP and by‐products of oxidation were also analyzed during various stages of the electrolysis reaction by HPLC and GC/MS techniques. Before the analysis by GC/MS technique, the samples were treated by solid phase microextraction (SPME) in order to concentrate the compounds from the reaction solution and identify all electrolysis intermediates. Current efficiencies (instantaneous current efficiency; ICE and total current efficiency; TCE) achieved during EO experiments were dependent on anode used and current density (20–40 mA cm?2) at 40°C. The results obtained demonstrated that the environmental electrochemical methods can be a feasible alternative for the wastewater treatment containing hazardous phthalates.  相似文献   
147.
To remove nitro aromatic compounds (NACs) from 2,4,6‐trinitrotoluene (TNT) red water, large‐pore‐size (pore size = 200 nm) polystyrene (PSt) microspheres were activated with chloroacetyl chloride followed by reaction with 1,2‐ethanediamine (EDA). Fourier transform IR analyses showed that the amino group was introduced onto PSt microspheres. Determination of the total amino group and primary amino densities suggested that the imino group was the functional group of EDA–PSt. Scanning electron microscope images and mercury porosimetry measurements indicated that the pore structure was well maintained during the reaction. After adsorption with EDA–PSt, 98.5% chemical oxygen demand and 99% acute toxicity of TNT red water was removed. As shown by HPLC and GC–MS, all the neutral and acid NACs in TNT red water were removed by EDA–PSt, while the basic NACs were not. The results showed that hydrogen bonding and electrostatic attraction were involved in adsorption. The adsorbed neutral and acid NACs were eluted using methanol and 0.1 mol L?1 NaOH, respectively.  相似文献   
148.
In this study the occurrence of diclofenac and sub‐products in effluent emerging from the University Hospital at the Federal University of Santa Maria was investigated. One metabolite was identified and, in aqueous solution, three degradation products. The quantification was conducted by means of HPLC‐DAD, and the determination of metabolite and degradation products by LC–ESI–MS/MS–QTrap. For the HPLC‐DAD method, a 70:30 mixture of methanol/sodium phosphate was used in isocratic mode. For the LC–ESI–MS/MS–QTrap determinations, a mobile phase, where phase A was an ammonium acetate solution 5 × 10?3 mol L?1, and phase B was methanol (5 × 10?3 mol L?1)/ammonium acetate (9:1, v/v), on gradient mode. The LDs for the HPLC and LC–MS/MS methods, respectively, were 2.5 and 0.02 µg L?1, the LQs, 8.3 and 0.05 µg L?1, and the linear range from 10 up to 2000 µg L?1 and 0.05 up to 10 µg L?1. As expected, the LC–ESI–MS/MS–QTrap method was more sensitive and less laborious. The metabolite 4′‐hydroxy‐diclofenac was identified. Photolysis was used for the degradation studies and three products of diclofenac were identified (m/z of 214, 286 and 303) in aqueous solution. These results notwithstanding, no degradation products of diclofenac were found in the hospital effluent.  相似文献   
149.
Biomass char (BC) deriving from fast pyrolysis of biomass was a potential adsorption material due to its relative high fixed‐carbon content and the inherent porous structures. Adsorption of phosphate from aqueous solution by BC was investigated in this paper. The results showed that the adsorption capacity of BC was dependent on pyrolysis conditions, such as temperature and holding time. The maximum adsorption capacity for phosphate was approximately 15.11 mg g?1 at 298 K. The pseudo‐second order model of the adsorption kinetics indicated that the adsorption process was complex and several mechanisms were involved. Equilibrium isotherm was satisfactorily followed the Freundlich isotherm model. The KF value in Freundlich equation gradually increased with elevating temperature. Moreover, the thermodynamic constants: ΔG0, ΔH0, and ΔS0 were evaluated as ?6.49 kJ mol?1 (at 298 K), 13.41 kJ mol?1, and 66.70 J mol?1 K?1, respectively. Phosphate adsorption onto BC was spontaneous and endothermic. As a waste, BC was a potentially attractive adsorbent for phosphate removal from aqueous solution with low cost and high capability.  相似文献   
150.
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