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71.
Svetlana F. Malysheva Natal’ya A. Belogorlova Nina K. Gusarova Alexander V. Artem’ev Alexander I. Albanov Boris A. Trofimov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1688-1693
Abstract Red phosphorus reacts with allylbenzene in the superbase system KOH-DMSO (130°C, 3 h, Ar) to give a mixture of bis(1-methyl-2-phenylethyl)phosphane (1), bis(1-methyl-2-phenylethyl)phosphane oxide (2), and 1-methyl-2-phenylethylphosphinic acid (3). Secondary phosphane oxide 2 and phosphinic acid 3 have been isolated from this mixture in 35% and 32% yield, respectively. Microwave activation of the reaction (200 W, 30 min) affords secondary phosphane 1 as the main product in 48% yield. GRAPHICAL ABSTRACT 相似文献
72.
Wenting Han Shuzhen Liao Chonghua Zhang Huazhi Ding Zhaoyang Wu Guoli Shen Ruqin Yu 《中国化学》2013,31(8):1072-1078
A new sensitive fluorometric assay method for acetylcholinesterase (AChE) and its inhibitor was developed using a fluorescent dye, nile red (NR). Due to the fluorescence resonance energy transfer between the NR and the gold nanoparticle (AuNPs), the fluorescence was quenched. AChE can break down acetylthiocholine to produce a thiol‐bearing compound, thiocholine. In the presence of thiocholine, the nile red is replaced from the AuNPs surfaces and simultaneously transformed to a derivative of nile red. The fluorescence intensity of the derivative is much stronger than that of the native nile red with the same concentration and its maximum emission wavelength has a blue shift so that the sensor achieves a good signal‐to‐background ratio. In addition, when organophosphate pesticide (OPs) exists, the activity of AChE can be inhibited, the generation of thiocholine will be prevented and no fluorescence enhancement occurs. The results show that the method is sensitive to AChE and paraoxon with the detection limits of 0.2 mU/mL and 0.05 ng/mL, respectively. 相似文献
73.
Richard H. Coupe 《International journal of environmental analytical chemistry》2013,93(13-14):883-896
The Soil and Water Assessment Tool (SWAT) was used to characterize the fate and transport of fluometuron (a herbicide used on cotton) in the Bogue Phalia Basin in northwestern Mississippi, USA. SWAT is a basin-scale watershed model, able to simulate hydrological, chemical, and sediment transport processes. After adjustments to a few parameters (specifically the SURLAG variable, the runoff curve number, Manning's N for overland flow, soil available water capacity, and the base-flow alpha factor) the SWAT model fit the observed streamflow well (the Coefficient of Efficiency and R 2 were greater than 60). The results from comparing observed fluometuron concentrations with simulated concentrations were reasonable. The simulated concentrations (which were daily averages) followed the pattern of observed concentrations (instantaneous values) closely, but could be off in magnitude at times. Further calibration might have improved the fit, but given the uncertainties in the input data, it was not clear that any improvement would be due to a better understanding of the input variables. 相似文献
74.
Guirong Li Yunfu Liu 《International journal of environmental analytical chemistry》2013,93(9):866-875
A new and highly sensitive inhibitory kinetic fluorescence method for the determination of arsenic (III) has been established based on its inhibitory effect on the oxidation reaction of Acridine red (ADR) by KBrO3 in sulphuric acid medium. The reaction has been followed by measuring the enhancement of fluorescence at 550?nm. It relies on the linear relationship where the change in the fluorescence (ΔF) versus added As(III) amounts in the range of 0–0.450?µg?mL?1 is plotted, under the optimum conditions. The sensitivity of the proposed method, i.e. the limit of detection, is 2.1?×?10?2?ng?mL?1. The method is featured with good accuracy and reproducibility for arsenic (III) determination. This method was successfully applied for the quantitative determination of arsenic (III) in food products samples, and the relative standard deviations and the recoveries were in ranges of 2.31–2.83% and 90.0–107.2%, respectively. A review of recently published catalytic or inhibiting kinetic methods for the determination of arsenic (III) has also been presented for comparison. The mechanism of reaction was studied. 相似文献
75.
Tong Shen Rong Xiao Qiong Wang Lijuan Yang Nong Wang 《Journal of Dispersion Science and Technology》2014,35(3):435-440
The absorption spectrum of Sudan red III (SR) in oil solutions and a series of O/W microemulsion with surfactant sodium dodecyl sulfate (SDS) has been determined by the UV-Vis spectrophotometer. We found that an association interaction existed between the stain SR and anionic surfactant SDS in water/mixed oil/SDS microemulsions. By measuring the absorbance of Sudan red in a series of microemulsions which has different R values and using the appropriate association models to analyze the experimental data, we obtain the association constants of SR and SDS, and the values of thermodynamics functions of associationΔr G m has also been calculated from the association constants. 相似文献
76.
Determination of the total tannin of white and red rind pomegranate (Punica granatum L.) has been carried out by colorimetry method using reagent 1,10 phenantroline. This method is based on reduction of iron (III) into iron (II) by tannin at temperature 800C for 20 min. Then the formed of iron (II) was reacted with 1,10 phenantroline to form orange red colour complex that could be measured by spectrophotometer visible at maximum absorption wavelength of 508 nm. The limit of detection (LOD) and the limit of quantitation (LOQ) obtained were 0.34 μg/mL and 1.14 μg/mL, respectively. This result was found to be linier with R value of 0.9984; accuracy as percent recovery was 84.69 ± 0.85% and coefficient of variant (KV) was 1.003% for white rind pomegranate while red rind pomegranate percent recovery was 84.38 ± 0,45% and coefficient of variant (KV) was 0.53%. The total tannin of white rind pomegranate was 18.28 ± 0.072%b/b and red rind pomegranate was 17.33 ± 0.081%b/b 相似文献
77.
Textile and dye industries are main sources of dye bearing effluent. In present studies the anaerobic biological degradation of Acid Red 3BN dye water (AR3BNDW) and mixed dye water (MDW) for reduction of color and COD were studied in sequential batch reactor (SBR). The sludge as sources of microorganism was arranged from maize processing bio methanation wastewater treatment plant, which was acclimatized for treatment of AR3BNDW and MDW. After the acclimatization, dyes degradation were studied in SBR At optimum operation condition of hydraulics retention time (HRT) = 2.5 d, and treatment time (tR) = 16 h, AR3BNDW have gone maximum 87% color reduction of 500 mg/L dye, and 82.8% COD reduction of 380 mg/L COD. At same operating condition, 84.5% color reduction of 500 mg/L dye, and 79.42% COD reduction of 413 mg/L COD achieved for MDW. The second order Grau model was fitted well for COD and dye reductions. The kinetics parameter were evaluated for both the dye water. 相似文献
78.
79.
《Journal of Saudi Chemical Society》2022,26(3):101475
This project explains an easy, simple and eco-friendly method to remove some toxic dyes like Brilliant Green and Acid Red from aquatic solution by technique of solid-phase extraction that uses Halloysite nanoclay eco-friendly solid phase as absorbent surface for adsorption of dye. The physical properties of the HNC such as scanning electron microscopy, transmission electron microscope, X-ray diffraction, Fourier transform infrared spectroscopy, and surface area analysis were studied. The best conditions like pH of the solution, HNC weight, contact shaking time, the temperature of the solution, and ionic strength were investigated for removal effectiveness. The experimental data of the adsorption process showed that HNC can remove most of the dyes within 30 min, with an adsorption capacity of 12.5 mg/g for A.R dye and 13.9 mg/g for B.G dye on HNC solid phase at optimum conditions. The removal process of dyes on HNC was studied kinetically and thermodynamically, and the data confirms that the pseudo-second-order kinetic model was able to describe the adsorption process. Thermodynamic data confirms the process was spontaneous andexothermic in nature for A.R dye, while was spontaneous and endothermic in nature for B.G dye. Finally, the effectiveness of HNC was inspected by removing dyes from three various real samples, and the results showed high performance in removing dyes on HNC for four consecutive cycles. 相似文献
80.
ZHANG Tianran YU Huacheng WANG Wenkai BAI Pu JIN Keyan ZHANG Jia-Nan YAN Wenfu 《高等学校化学研究》2022,38(6):1532-1541
It is highly desired yet challenged to find an adsorbent with low cost and excellent performance in the removal of organic dyes from aqueous solution. Here we reported that a layered cationic aluminum oxyhydroxide material hydrothermally synthesized from the low-cost source materials of AlCl3∙6H2O, CaO and H2O, known as JU-111, can meet such criterion in removing methyl orange(MO) and Congo red(CR). JU-111 shows fast adsorption kinetics[especially for CR(15 s)] and high adsorption capacity(MO:>1000 mg/g; CR:>2900 mg/g), surpassing most of the reported adsorbents. Comprehensive characterizations of the adsorption process of MO and CR revealed that both adsorptions were achieved via the anion exchange process. The characteristics of extremely low cost and excellent performance render JU-111 great potential in the practical applications in the removal of anionic dyes. 相似文献