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101.
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103.
采用微波消解-火焰原子吸收光谱(FAAS)法对大别山区3种中药(何首乌、黄精和拐枣)中的微量元素进行测定。用微波消解仪处理样品,对消解条件及消解程序进行优化,在最佳微波消解条件下,结合FAAS法测定上述3种中药中Ca、Mg、Cu、Zn、Fe、Mn 6种元素的含量。结果表明,微波消解的最佳条件为:何首乌和拐枣采用HNO3-H2O2混酸体系,配比分别为5∶2和5∶3,固液比1∶20,最高功率(700W)时的保温时间分别为8min和6 min;黄精采用HNO3-HCl,混酸体系,配比5∶2,固液比1∶28,保温时间为8 min。所建立的定量分析方法回收率为95.63%~101.36%,相对标准偏差小于3.0%,线性相关系数大于0.999,方法检出限为0.18~2.20 ng/mL。3种中药中均含有丰富的微量元素,尤其是黄精中Fe、Ca和Mn的含量较高;何首乌中Mg、Zn和Fe含量相对较高;拐枣中Fe和Ca含量相对较高。研究结果可为上述3种中药中微量元素的含量与其药效的相关性提供科学依据。 相似文献
104.
为测定补阴类中药中Zn、Fe、Cu、Mn 4种微量元素的含量,采用V(HNO3)+V(HClO4)=4+1混合酸常压微沸条件下消解样品,运用火焰原子吸收光谱法测定了补阴类中草药女贞子、桑寄生、木蝴蝶中Zn、Fe、Cu、Mn 4种微量元素的含量。结果表明,3种中草药Fe含量最高,Zn、Mn次之,Cu含量最低。该法的加标回收率在95.2%~105.4%之间,RSD<2.000 0%,具有良好的准确度和精确度。结果为这类中药保健作用的进一步开发提供了参考。 相似文献
105.
建立了液相色谱-串联质谱(LC-MS/MS)同时测定4种中草药(甘草、银杏叶、菊花和八角茴香)中155种农药残留方法。样品采用乙腈、无水硫酸镁和乙酸钠分散固相萃取(DSPE),再经Cleanert TPH固相萃取(SPE)柱净化,乙腈/甲苯(8:1,V/V)洗脱,液相色谱串联质谱多反应监测模式下测定,外标法定量。实验结果表明,155种农药的检出限(S/N=3)和定量限(S/N=10)范围分别为0.4~34.1μg/kg和1.3~113.7μg/kg;在1.0~2400.0μg/kg浓度范围内,155种农药中有148种农药在4种中草药中线性相关系数平均值R2≥0.9950;在低、中、高3个添加水平,86.5%~97.4%的农药平均回收率在60%~120%范围,94.2%~100.0%的农药相对标准偏差RSD≤20%(n=5)。该方法适用于中草药中农药多残留检测。 相似文献
106.
《Analytical letters》2012,45(10):1769-1782
The adulteration of traditional herbal medicines (THMs) with synthetic drugs is prevalent and represents a serious risk for public health. A rapid and novel reversed-phase high-performance liquid chromatography (HPLC) method was established and validated for the simultaneous determination of five nonsteroidal anti-inflammatory drugs (NSAIDs) and two glucocorticoids in THMs for rheumatoid treatment. Glipizide was used as the internal standard (IS). The separation was completed on a C18 column with a mobile phase consisting of methanol and a buffer solution containing 10 mM ammonium acetate and 0.1% formic acid with a gradient elution. All calibration curves showed good linear regression (r 2 > 0.9996), and the recoveries of the seven analytes were in the range of 96.94%–105.37%. A liquid chromatography-mass spectrometry (LC-MS) method was developed to confirm the identity of the adulterants. The proposed method was applied to identify and determine the five NSAIDs and two glucocorticoids in THMs for rheumatism. 相似文献
107.
《Analytical letters》2012,45(6):993-1002
Optimization of the extraction time of rutin and quercetin from herbal plant (Inflorescentia tiliae, Violae tricoloris herba, Anthodium arnica, Flos sambuci, Herba rutae, and Herba hyperici) is described. Determination of aforementioned flavonols was performed by pharmacopoeial, spectrophotometric, and chromatographic methods. The highest quercetin concentration was obtained for Inflorescentia tiliae whereas Herba hyperici contains the highest amount of rutin. The methods were tested on pharmaceutical preparations. The obtained results were compared by statistical test. 相似文献
108.
《Analytical letters》2012,45(14):2475-2492
Abstract Recently, the fingerprinting approach using chromatography has become one of the most potent tools for quality assessment of herbal medicine. Due to the complexity of the chromatographic fingerprint and the irreproducibility of chromatographic instruments and experimental conditions, several chemometric approaches such as variance analysis, peak alignment, correlation analysis, and pattern recognition were employed to deal with the chromatographic fingerprint in this work. To facilitate the data preprocessing, a software named Computer Aided Similarity Evaluation (CASE) was also developed. All programs of chemometric algorithms for CASE were coded in MATLAB5.3 based on Windows. Data loading, removing, cutting, smoothing, compressing, background and retention time shift correction, normalization, peak identification and matching, variation determination of common peaks/regions, similarity comparison, sample classification, and other data processes associated with the chromatographic fingerprint were investigated in this software. The case study of high pressure liquid chromatographic HPLC fingerprints of 50 Rhizoma chuanxiong samples from different sources demonstrated that the chemometric approaches investigated in this work were reliable and user friendly for data preprocessing of chromatographic fingerprints of herbal medicines for quality assessment. 相似文献
109.
十六种活血化瘀中草药中微量元素的测定 总被引:10,自引:0,他引:10
用原子吸收光谱法对十六种活血化瘀中草药中十种微量元素进行了测定。方法的回收率为95.0% ̄105.0%,相对标准偏差小于0.03%,结果表明,该法具有操作简单,快速和准确度高等优点。 相似文献
110.
Summary A capillary zone electrophoretic method for the analysis of phenolic acids in soil and plant extracts was developed with direct
UV detection using a phosphate electrolyte solution. The electrophoretic separation required the phenolic acids to be charged
at a pH above their pKa in order to achieve their migration towards the anode. Electroosmotic flow (EOF) was reversed in direction by adding tetradecyltrimethylammonium
bromide (TTAB). Factors affecting the separation selectivity, including the buffer pH and EOF modifiers, were investigated
systematically. Eight phenolic acids were separated and detected in 10 min using an electrolyte containing 25 mM phosphate,
0.5 mM TTAB and 15% acetonitrile (v/v) at pH of 7.20. Linear plots for the test phenolic acids were obtained in a concentration range of 0.01–1 mM with detection
limits in the range of 1.0–7.0 μM. The recoveries ranged from 92.8 to 102.3% in soil and plant tissues samples spiked at 100
μM and the relative standard deviation based on the peak area were ranged 2.0 to 4.5%. The proposed method was used for the
determination of phenolic acids in plant tissue and soil extracts with direct injection. 相似文献