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21.
We developed a simple, rapid and reliable method for determination of 20 common amino acids based on derivatization with 9‐fluorenylmethyl chloroformate (FMOC‐Cl) and RP‐LC/UV, this method was first introduced into quantitative analysis of amino acids. The amino groups of amino acids were trapped with FMOC‐Cl to form amino acid‐FMOC‐Cl adducts which can be suitable for LC‐UV. Chromatographic separation was performed on a C18 column with a mobile phase gradient consisting of acetonitrile and sodium acetate solution. This method was shown to be sensitive for 20 common amino acids. In the intra‐day precisions assay, the range of RSDs was 3.21‐7.67% with accuracies of 92.34‐102.51%; for the inter‐day precisions assay, the range of RSDs was 5.82‐9.19% with accuracies of 90.25‐100.63%. The results also indicated that solutions of amino acids‐FMOC‐Cl can be kept at room temperature for at least 24 h without showing significant losses in the quantified values. The validated method was successfully applied to the determination of major four kinds of amino acids in R. isatidis samples (Arg, Pro, Met and Val). The total content of amino acids in different origin R. isatidis was 13.32‐19.16 mg/g. The differences between R. isatidis samples were large using HCA. 相似文献
22.
Polyacetylenes are main toxic ingredients in Bupleurum longiradiatum, a poisonous plant that has ever been misused as substitutes for Chaihu (Bupleuri Radix). For the first time, a high-performance liquid chromatography method coupled with diode array detector and mass spectrometry (HPLC-DAD-MS) was developed for qualitative and quantitative analysis of nine polyacetylenes in Bupleurum species. All references, including two new polyacetylenes, were isolated from B. longiradiatum and purified using a semi-preparation HPLC chromatography. The analysis was performed on a TSKgel ODS-100V C18 column (3 μm, 150 mm x 4.6 mm i.d.) using a gradient system of acetonitrile and water, with diode array detection (254 nm). The method was validated for linearity, precision, accuracy, limit of detection and quantification. A total of 27 Bupleurum samples were examined with this method, which showed a great variety in the distribution and contents of the polyacetylenes. It was found that polyacetylenes (1-8) were the main ingredients in B. longiradiatum, while a few kinds of polyacetylenes (5-8) were also identified in B. smithii, B. smithii var. parvifolium, B. bicaule and B. angustissimum. However, no polyacetylenes (1-9) were detected in the authentic Chaihu samples and the other Bupleurum species. The results indicated that the toxic B. longiradiatum could readily be distinguished from other medicinal Bupleurum species based on the polyacetylene profiles, and the guidelines and quality control of polyacetylenes for Chaihu are useful. The acute toxicity of the ethanol extract of B. longiradiatum and its fractions was also investigated. 相似文献
23.
24.
本文采用了薄层色谱法将复方制剂活血逐瘀颗粒中的芍药甙与其他成分分离,用紫外分光光度法测定芍药甙的含量,其平均回收率为98.74%,变异系数为1.43%,本文方法抗干扰能力强,适合于中药复方制剂中芍药甙的定量分析。 相似文献
25.
采用正交试验法,对板蓝根靛玉红超临界CO2萃取工艺进行优化。选用萃取温度、萃取压力、萃取时间作为正交试验的3个因素,每个因素选3个水平,以提取物中靛玉红的含量来确定最佳提取条件,并且在最佳条件下确定所加夹带剂的最佳剂量。结果表明最佳工艺为:萃取温度45℃、萃取压力35MPa、萃取时间3h,夹带剂为75%的乙醇200mL。最佳工艺条件下提取靛玉红的得率为4.95μg/g,为传统提取方法的1.6倍。 相似文献
26.
采用高效液相色谱法测定丹参超微粉体和常规粉体中丹参酮ⅡA体外溶出量和溶出速率.丹参超微粉体和常规粉体中丹参酮ⅡA体外溶出量无显著性差异,超微粉体的溶出速率较常规粉体明显增加.实验表明超微粉碎可明显提高丹参酮ⅡA溶出速率. 相似文献
27.
Cheng Qu Hui Yan Shao‐Qing Zhu Yi‐Yun Qian Gui‐Sheng Zhou Sheng Guo Zhen‐Hua Zhu Sen Zhang Da‐Wei Qian Jin‐Ao Duan 《Journal of separation science》2019,42(6):1122-1132
A rapid and sensitive ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry method was established and employed to determine 21 nucleosides, nucleobases, and amino acids in 60 samples from different parts of Angelicae Sinensis Radix. The established methods were validated by good linearity (r2 > 0.9937), limits of detection (0.12–77.75 ng/mL), limits of quantitation (0.31–272.13 ng/mL), intra‐ and interday precisions (RSD ≤ 4.84%, RSD ≤ 6.26%), stability (RSD ≤ 5.92%), repeatability (RSD ≤ 7.14%), recovery (91.4–103.4%), and matrix effects (0.92–1.03). Chemical comparative analysis revealed that the content of total analytes in four parts of Angelicae Sinensis Radix were different, and exhibited the order: Head (14.89 mg/g) > Body (10.15 mg/g) > All (8.22 mg/g) > Tail (6.23 mg/g). Principal component analysis showed that the samples could be classified into four groups in accord with four different parts of Angelicae Sinensis Radix. The results could provide a scientific basis and reference for the quality control of Angelicae Sinensis Radix, and may be conducive to further research on the pharmacological activities of Angelicae Sinensis Radix. 相似文献
28.
A purge and trap technique to capture volatile compounds combined with comprehensive two‐dimensional gas chromatography/time‐of‐flight mass spectrometry to investigate the effect of sulfur‐fumigation on Radix Angelicae Dahuricae 下载免费PDF全文
Gang Cao Qinglin Li Jida Zhang Hao Cai Baochang Cai 《Biomedical chromatography : BMC》2014,28(9):1167-1172
Sulfur‐fumigation is known to reduce volatile compounds that are the main active components in herbs used in herbal medicine. We investigated changes in chemical composition between sun‐dried and sulfur‐fumigated Radix Angelicae Dahuricae using a purge and trap technique to capture volatile compounds, and two‐dimensional gas chromatography/time‐of‐flight mass spectrometry for identification. Using sun‐dried Radix Angelicae Dahuricae samples as a reference, the results showed that 73 volatile compounds, including 12 sulfide compounds, were found to be present only in sulfur‐fumigated samples. Furthermore, 32 volatile compounds that were found in sun‐dried Radix Angelicae Dahuricae samples disappeared after sulfur‐fumigation. The proposed method can be applied to accurately discriminate sulfur‐fumigated Radix Angelicae Dahuricae from different commercial sources. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
29.
建立了超高效液相色谱-串联质谱(UHPLC-MS/MS)快速检测洛党参中乙基多杀菌素-J(XDE-175-J)和乙基多杀菌素-L(XDE-175-L)残留的方法。样品经乙腈提取,乙二胺-N-丙基硅烷和石墨化炭黑净化后,外标法定量。结果表明,XDE-175-J和XDE-175-L的峰面积与其质量浓度分别在0.075~75μg/L和0.025~25μg/L范围内,呈良好线性关系(r20.990);在0.375、3.75、75μg/kg加标水平下,XDE-175-J的平均回收率为88.4%~113.5%,相对标准偏差(RSD,n=5)为2.0%~4.2%;在0.125、1.25、25μg/kg加标水平下,XDE-175-L的平均回收率为84.4%~99.5%,RSD(n=5)为2.5%~4.9%。乙基多杀菌素的定量下限(LOQ)为0.375μg/kg(XDE-175-J)和0.125μg/kg(XDE-175-L)。该方法简便、快捷,灵敏度高,回收率和重复性良好,能满足农药残留检测技术要求,可用于大量洛党参样品中乙基多杀菌素的残留分析。 相似文献
30.
An improved quality control method was developed to simultaneously determine 15 major constituents (eight flavonoids and seven saponins) in various radix Astragali preparations, using SPE for pretreatment of samples, HPLC with diode-array and evaporative light scattering detectors (DAD-ELSD) for quantification in one run, and HPLC-ESI-TOF/MS for definite identification of compounds in preparations. Optimum separations were obtained with a ZORBAX C(18) column, using a gradient elution with 0.3% aqueous formic acid and ACN. This established method was fully validated with respect to linearity, precision, repeatability, and accuracy, and was successfully applied to quantify the 15 compounds in 19 commercial samples, including 3 dosage forms, i. e., oral solution, injection, concentrated granule, and its processed products of radix Astragali. The results demonstrated that many factors might result in significant differences in quality of the final preparations, including crude drugs, pretreatment processes, manufacturing procedure, storage conditions, etc. Then the developed method provided a reasonable and powerful manner to ensure the efficacy, safety, and batch-to-batch uniformity of radix Astragali products by standardizing each procedure, and thus should be proposed as quality control for the clinical use and modernization of herbal preparations. 相似文献