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101.
超高效液相色谱-串联质谱法测定水产品中孔雀石绿、结晶紫及其代谢物残留量 总被引:1,自引:0,他引:1
采用超高效液相色谱-串联质谱法同时检测水产品中孔雀石绿、结晶紫及其代谢物(隐色孔雀石绿、隐色结晶紫)。经匀浆处理的水产品样品,用乙腈提取,加入酸性氧化铝去除油脂,旋转蒸发器蒸干后,用甲酸-乙腈-水(0.1+10+89.9)溶液溶解,样品溶液用超高效液相色谱分离,电喷雾串联四极杆质谱进行检测。以氘代孔雀石绿、氘代隐色孔雀石绿为内标物。孔雀石绿、结晶紫及其代谢物的质量浓度均在5.0μg·L-1以内与其峰面积呈线性关系,检出限(3S/N)在0.10~0.12μg.kg-1之间。以空白水产品样品为基体进行回收试验,方法的回收率在90.2%~108.0%之间,相对标准偏差(n=6)在2.3%~7.6%之间。 相似文献
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《Analytical letters》2012,45(5):955-969
ABSTRACT Simple, sensitive and selective methods for the determination of trimethoprim (TMP) in pure form and in pharmaceutical formulations are described. The methods are based on the reaction of TMP as a π-electron donor with bromothymol blue (BTB), bromocresol green (BCG) and alizarin red S (ARS) as electron acceptors. The coloured products are quantified spectrophotometrically at their corresponding λmax. Beer's law is obeyed in case of BTB in the range 2.9-23.2 μg/ml (CHCl3), 2.9-20.0 μg/ml (CH2Cl2) and 5.0-29.0 μg/ml (ClC6H5), in the case of BCG 2.9-27.5 μg/ml (H2O/alc.), 2.9-18.3 μg/ml (CHCl3) and 2.9-20.3 μg/ml (CH2Cl2) and for ARS in the range 3.0-12.0 μg/ml in H2O/alc medium. The specific absorptivities, molar absorptivities, Sandell sensitivities, standard deviations and percent recoveries are evaluated. Application of the suggested methods to dosage forms is presented and compared with the pharmacopoeial method. The interference from additives and sulfa compounds, especially sulfamethoxazole, has been overcome by extraction into chloroform or methylene chloride. 相似文献
106.
《Analytical letters》2012,45(14):2621-2633
Abstract A sensitive and selective voltammetric method for determination of antimony(III) using Alizarin Red S (ARS) as complexing agent is described. The method is based on the monitoring the oxidation peak of antimony(III)-ARS complex at ?520 mV in ammonium-ammonia buffer (pH = 7.5). The peak current was measured by scanning the potential from ?700 mV versus Ag/AgClto more positive potentials without accumulation in the presence of 1 × 10?6 mol L?1 of ARS. The limit of detection (3 s) and limit of quantification (10 s) of the method were calculated from calibration curve as 1.45 µg L? and 4.8 µg L? respectively. The calibration plot for antimony(III) was linear in the range of 4.8–30 µg L?. The interference of various ions was examined. Serious interference from Al(III), Fe(III), Cu(II), Pb(II), and Zn(II) was eliminated by addition of EDTA to the solution. The method was applied to drinking water samples. The recoveries were in the range 94% – 105%. The results obtained from the developed method were compared with those from the differential-pulse anodic-stripping method and no statistically significant difference was found. 相似文献
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《Analytical letters》2012,45(8):1625-1633
ABSTRACT Aluminium was determined in a weakly alkaline medium by reaction with alizarin at trace level. Flotation of the complex was carried out with heptane, followed by dissolution in N, N-dimethylformamide (DMF) for subsequent spectrophotometric determination. The molar absorptivity was 2.92×105 mol? cm? at 518 run. Beer's law was obeyed in the range 5–80 μg/1 and the detection limit was 0.4μg/l. The reliability of the procedure was confirmed by determination of a sample of milk with Graphite Furnace Atomic Absorption Spectrophotometric method (GFAAS). The precision and accuracy of the method were both acceptable via F and tests at the 95% confidence level. 相似文献
108.
《Analytical letters》2012,45(4):677-689
ABSTRACT Indirect determination of total monomelic and acid-reactive aluminum in natural waters by a.c. oscillopolarography in the presence of pyrocatechol violet (PCV) is presented in this paper. In 0.5 mol 1?1 NH4Ac buffer solution (pH 6.4) containing l×lO?3 mol 1?1 PCV, PCV yields two incisions on the a.c oscillogram at the potentials of - 0.80 and - 1.20 V, respectively. The incision depth declines when adding aluminum in the solution. The decreases of incision depth (Ep = -1.20 V) has a linear relationship with increasing Al concentrations (4×10?7 - 4×10?6 mol 1?). It is the basis for indirect quantitative analysis. The relative standard deviation is 8.3% for 1×10?6 mol 1?1 Al (n = 10) and the detection limit is 2 × 10?7 mol 1?1. The proposed method has been applied to determine total and acid-reactive Al in natural waters and the results are compared with Driscoll's 8-HQ-MIBK-GF/AAS and PCV colorimetric methods. 相似文献
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《Analytical letters》2012,45(10):779-795
Abstract A perbromate- selective membrane electrode with a liquid membrane of crystal violet-perbromate dissolved in chlorobenzene is described, The liquid membrane electrode exhibits rapid and near Nernstian response to perbromate activity from 10?5 to 10?2 M. The response is unaffected by pH in the range 2–10, Major interferences are periodate and perchlorate. A kinetic study of the iron(II)- perbromate reaction was carried out with the perbromate electrode, A potentiometric method is described for the determination of 50–500 μg of iron (II) with relative errors and standard deviations of 1–2%. 相似文献