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41.
Novel visible-light-driven photocatalyst of NiO/Cd/g-C3N4 for enhanced degradation of methylene blue
《Arabian Journal of Chemistry》2020,13(6):5810-5820
Novel NiO/Cd/g-C3N4 photocatalysts were synthesized using a green and straightforward microwave-assisted method and characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), the Brunauer–Emmett–Teller (BET) method, transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and ultraviolet–visible spectroscopy (UV–Vis). The ternary NiO/Cd/g-C3N4 nanocomposites were evaluated for the degradation of methylene blue (MB) at room temperature under the visible light irradiation. Experimental results revealed that the weight percent of cadmium had a remarkable effect on the photodegradation efficiency. The NiO/Cd/g-C3N4 (0.1%) sample exhibited superior activity in the degradation reaction. The activity of this nanocomposite was about 4.5 and 3.25 fold higher than those of the pure g-C3N4 and NiO/g-C3N4 samples in the degradation of MB, respectively. The enhanced photocatalytic activity was attributed to the low energy gap, increased absorption capacity of the visible light, and efficient suppression of the recombination of photogenerated electron-hole pairs. A detailed photocatalytic mechanism over the nanocomposite of NiO/Cd/g-C3N4 (0.1%) was proposed with superoxide radical anion O2– as the main reactive species. The stability of the nanocomposite was confirmed after four consecutive runs as well. 相似文献
42.
Potentiodynamic deposition of Prussian blue from a solution containing single component of ferricyanide and its mechanism investigation 总被引:1,自引:0,他引:1
Dai?Zhang Kang?Wang Dacheng?Sun Xinghua?XiaEmail author Hongyuan?Chen 《Journal of Solid State Electrochemistry》2003,7(9):561-566
Potentiodynamic techniques were used for the direct electrodeposition of Prussian blue nano-clusters from an acidic solution of ferricyanide. Electrochemical, EQCM, IR, AFM, and UV/vis measurements were carried out to characterize deposited nano-sized Prussian blue and to explore the formation mechanism. Results showed that ferricyanide could partially dissociate to free ferric and cyanide ions. The driving force of this dissociation is the formation of PB and the evolution of HCN. The optimal potential window for the potentiodynamic formation of PB from an acidic solution (pH 1.6) is between –0.5 V and 0.4 V. In addition, the influence of surface adsorption of CN- ions on the formation of PB was discussed.Dedicated to Professor W. Vielstich on the occasion of his 80th birthday. 相似文献
43.
Utilization of one waste material to control pollution caused by another is of high significance in the remediation of environmental
problems. Rice husk, an abundantly available agricultural waste, can be used as a low cost adsorbent for dyes and heavy metals
in effluent streams. The possible utilization of rice husk ash as an adsorbent for methylene blue dye from aqueous solutions
has been investigated. Ash samples from husks of two origins were prepared at different temperatures and their physical, chemical
spectroscopic and morphological properties were determined. XRD, FTIR and SEM were some of the techniques adopted for the
characterization. The samples were also analyzed for bulk density, pH, nitrogen adsorption properties and lime reactivity.
Experiments of methylene blue adsorption on the ash samples were conducted using batch technique and a comparative study was
made. Results were analyzed using linear, Langmuir and Freundlich isotherms. The values of separation factor indicate that
most of the ash samples do adsorb the dye molecules, but in varying quantities. Calcination at 900∘C reduces the adsorption capacity of the ash to a great extent. Regression analysis shows that the experimental data fits
both Langmuir and Freundlich isotherms for certain concentration limits. The adsorbate species are most probably transported
from the bulk of the solution into the solid phase through intra-particle diffusion process. Kinetics of adsorption was found
to follow pseudo second order rate equation with R
2∼ 0.99. The highest adsorption capacity (Q
0) achieved is found to be ∼690 mg/g, which is even higher than the values reported for activated carbon from rice husk. The
adsorption capacity of the ash samples are in good agreement with their surface area and pore volume. 相似文献
44.
水中阴离子表面活性剂的吸附分光光度法测定 总被引:7,自引:0,他引:7
研究萘基二苯甲烷与阴离子表面活性剂的缔合反应及缔合物在聚合物颗粒表面的吸附及洗脱 ,提出了碱性艳蓝BO分光光度法测定河水中的阴离子表面活性剂 ;碱性艳蓝BO与十二烷基苯磺酸钠、十二烷基硫酸钠、十二烷基磺酸钠的缔合物的表观摩尔吸光系数分别为3.76×104、3.63×104、2.15×104L·mol -1·cm -1 ,方法的线性范围为0.0~2.0mg/L,相对标准偏差3.8% (n=8);应用该法测定河水中阴离子表面活性剂含量 ,结果令人满意 相似文献
45.
A series of carbon-covered titania (CCT) were prepared via pyrolysis of sucrose highly dispersed on titania surface in flowing
N2. The samples were characterized by XRD, BET, DTA-TG, UV—Vis, and their photocatalytic properties were evaluated with two
model pollutants, methylene blue (MB) and rhodamine B (RB), at room temperature. The effect of carbon content on photocatalytic
activity of the C/TiO2 composite was investigated. It was found that the effect of carbon content is different for different pollutants or different
light sources. For three tested samples, under UV illumination CCT01 has the highest activity for MB photocatalytic degradation,
while in the case of RB, CCT02 is the most active photocatalyst. Under visible light illumination, CCT005 has the highest
activity for both MB and RB photocatalytic degradation.
Translated from Chinese Journal of Catalysis, 2006, 27(1): (in Chinese) 相似文献
46.
47.
Calorimetric measurements of the enthalpy of adsorption on montmorillonite indicate different patterns for methylene blue
(MB) and crystal violet (CV). The enthalpy of adsorption of MB is endothermic up to 73% of the cation exchange capacity (CEC)
(i.e., about 0.6 mmol g-1 clay), whereas at higher adsorption ratios the adsorption reaction becomes exothermic. The enthalpy of adsorption of CV is
exothermic for all amounts adsorbed. These results were confirmed with adsorption experiments that prove that adsorption of
MB increase with temperature, whereas CV adsorption decreases. This behavior indicates changes in the equilibrium coefficient
according to Van't Hoff's equation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
48.
Based on the similarity in properties of arsenate and phosphate, the colorimetric method using the molybdene blue complex was tested in order to determine low As(V) concentration in waters. The influence of complex formation time, daylight, temperature and competitive anions (silicate and sulphate) upon complex formation was determined. Optimal complex formation was reached in 1 h at 20±1 °C and was slightly favoured when developed in daylight. The formation rate declined with decreasing reaction temperature and no influence of any of the competitive anions tested (at concentrations usually found in natural waters of granitic areas) was noted. The detection limit of this method was 20 μg As(V) l−1. This simple, fast and sensitive arsenic determination method is suitable for field analysis, especially for waters containing low levels of phosphate and organic matter. Through arsenate determination, this colorimetric method allowed the arsenite oxidation efficiency of five common industrial oxidants to be compared. H2O2 and MnO2(s) were not considered as effective oxidants as a high excess was necessary to ensure As(III) oxidation. NaOCl and KMnO4 were promising oxidants as they allowed complete arsenite oxidation with a small excess for NaOCl or even less than the electron stoichiometric ratio in the case of KMnO4. FeCl3 was the most effective oxidant among the reagents tested here. 相似文献
49.
N. I. Surovtseva A. M. Eremenko N. P. Smirnova V. A. Pokrovskii T. V. Fesenko G. N. Starukh 《Theoretical and Experimental Chemistry》2007,43(4):235-240
The effect of nanosized porous films (average density 10 g/m2) of TiO2. TiO2/SiO2, and SiO2 on the photostability of adsorbed methylene blue (MB) dye during UV irradiation in air was investigated by optical spectroscopy
and laser-induced mass spectrometry. The effectiveness of the photodecomposition of MB decreases in the order TiO2 > TiO2/SiO2 > SiO2 with rate constants 1E-2, 0.6E-2, and 0.3E-2 min−1 respectively. A mechanism including the participation of both excited states of the dye molecules and photoexcited titanium
dioxide is proposed for the photodecolorization of MB adsorbed on the surface of the investigated films.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 4, pp. 220–225, July–August, 2007. 相似文献
50.
阿利新蓝 (AlcianBlue)是一种从植物中提取出的天然物。于 1 944年由Haddock和Wood在实验室通过多次实验后所发现。它的水溶液呈天蓝色 ,着色性好而且吸光系数很大。又因它较好的水溶性。所以可以作为高效的生物染色剂[1,2 ] ,用于粘蛋白染色、细菌染色及聚酯、纤维素等人造和天然纤维的染料[3 ] 。基于它的重大应用前景和较高的商业价值 ,探索出一条合理的工业化合成路线就非常重要了。有关阿利新蓝的应用虽然有很多 ,但始终未见合成阿利新蓝的文献报道。在设计它的有机合成时必然涉及酞菁铜 (PcCu)的氯甲基化反… 相似文献