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101.
A simple and rapid high-performance thin-layer chromatographic method for quantification of gallic acid and ellagic acid in dried fruits of Terminalia chebula, Phyllanthus emblica, and Quercus infectoria has been developed. The chromatographic development was carried out on precoated silica gel 60 F254 plates in a mixture of toluene:ethyl acetate:chloroform:formic acid (4:8:1:3 v/v/v/v). The plate was scanned densitometrically at a wavelength of 280 nm. The retention factor value of gallic acid and ellagic acid was found to be 0.63 ± 0.2 and 0.53 ± 0.1, respectively. The developed method was validated in terms of linearity, precision, accuracy, sensitivity, robustness, specificity and stability as per the international conference of harmonization guidelines. The method showed good linear relationship over a range of 100–600 ng/band (gallic acid) and 100–500 ng/band (ellagic acid) with a regression coefficient (r2) of 0.997 (gallic acid) and 0.996 (ellagic acid). The method showed high accuracy (99.65%–100.85%). The percentage relative standard deviation of intra-day and inter-day precision studies was not more than 2%. The method is highly robust and has displayed high specificity. The developed method is new, simple, and accurate and can be successfully employed in routine analysis of raw materials and formulations containing gallic acid and ellagic acid. 相似文献
102.
Three kinds of sanshools were separated from Zanthoxylum bungeanum oleoresin by high-speed countercurrent chromatography. Sanshools are a series of amide compounds extracted from the Zanthoxylum bungeanum. Due to similar structures, polarities, and dissociation constants, it was challenging to select an appropriate solvent system for their complete separation by countercurrent chromatography. To address this challenge, a solvent-system-selection strategy was proposed to identify a relatively suitable solvent system. Additionally, a separation procedure incorporating multi-elution modes selection was established to separate similar compounds in a logical order. Ultimately, a solvent system comprising n-hexane:ethyl acetate:methanol:water in a ratio of 19:1:1:5.67 was selected. Three amide compounds with high purity were obtained through the use of recycling elution mode to improve separation resolution: hydroxy-ε-sanshool (8.4 mg; purity: 90.64%), hydroxy-α-sanshool (326.4 mg; purity: 98.96%), and hydroxy-β-sanshool (71.8 mg; purity: 98.26%) were obtained from 600 mg sanshool crude extract. The summarized solvent-system-selection strategy and separation procedure incorporating multi-elution modes may instruct countercurrent chromatography users, particularly novices, seeking to separate compounds with highly similar chemical properties. 相似文献
103.
Mona M. Amer Ahmed A. Habib Sherin F. Hammad Amira H. Kamal 《Journal of separation science》2023,46(14):2300135
A green micellar stability-indicating high-performance liquid chromatography method was developed for rupatadine fumarate determination in existence with its main impurity desloratadine. Separation was attained using Hypersil ODS column (150 × 4.6 mm, 5 μm), the micellar mobile phase consisted of 0.13 M sodium dodecyl sulfate, 0.1 M disodium hydrogen phosphate adjusted by phosphoric acid to pH 2.8 and 10% n-butanol. The column was maintained at 45◦C and detection was carried out at 267 nm. A linear response was achieved over the range of 2–160 μg/ml for rupatadine and 0.4–8 μg/ml for desloratadine. The method was applied for rupatadine determination in alergoliber tablets and alergoliber syrup without the interference of methyl paraben and propyl paraben present as main excipients. Rupatadine fumarate revealed pronounced susceptibility to oxidation; further study of oxidative degradation kinetics was carried out. Rupatadine was found to follow pseudo-first-order kinetics when exposed to 10% H2O2 at 60 and 80°C and the activation energy was found to be 15.69 Kcal/mol. At a lower temperature (40°C), degradation kinetics regression was best fitted as a polynomial quadratic relationship, thus rupatadine oxidation at a lower temperature tends to adopt a second-order kinetics rate. Oxidative degradation product structure was revealed using infrared and found to be rupatadine N-oxide at all temperature values. 相似文献
104.
Shaobin Pan Zhe Zhang Qixiang Feng Jin Zhao Shahid Aziz Liwen Dou Jing Li Luyao Huang Huijiao Yan Xiao Wang Jia Li Daijie Wang 《Journal of separation science》2023,46(10):2300042
Cyperus rotundus L. has been extensively used in ancient medication for the treatment of different disorders worldwide, in which sesquiterpenes are the most representative components. In this study, sesquiterpenes were effectively purified by two-dimensional counter-current chromatography in combination with continuous injection and inner-recycling mode with a solvent system of n-hexane/ethyl acetate/methanol/water (1:0.2:1:0.2, v/v/v/v). For one-dimension separation, continuous injection mode was used with three times injection and the inner-recycling mode was adopted for the separation of two mixtures for two-dimensional separation. Finally, four sesquiterpenoids, including scariodione ( 1 ), cyperenoic acid ( 2 ), scariodione ( 3 ), and α-cyperone ( 4 ), were obtained with purities over 98%. Mass spectrometry and nuclear magnetic resonance were applied to identify their structures. The results from the anti-inflammation effect with zebrafish demonstrated that cyperenoic acid exhibited stronger anti-inflammation activity. Molecular docking results suggested that cyperenoic acid possessed lower binding energies –9.4545 kcal/mol with 1CX2 to form formed hydrogen bond interaction with ARG120. In general, all the obtained findings proved that the strong anti-inflammation capacity of cyperenoic acid can have the potential of being adopted for treating diseases resulting from inflammation. 相似文献
105.
Fansheng Ning Heng Zhu Huijiao Yan Jiguo Liu Shahid Aziz Hidayat Hussain Xiangyun Song Lei Xie Zhaoqing Meng Guiyun Cao Daijie Wang 《Journal of separation science》2023,46(16):2300053
In this work, the preparative separation of quinolyridine alkaloids from seeds of T. lanceolata by conventional and pH-zone-refining counter-current chromatography. Traditional counter-current chromatography separation was performed by a flow-rate changing strategy with a solvent system of ethyl acetate-n-butanol-water (1:9:10, v/v) and 200 mg sample loading. Meanwhile, the pH-zone-refining mode was adopted for separating 2.0 g crude alkaloid extracts with the chloroform-methanol-water (4:3:3, v/v) solvent system using the stationary and mobile phases of 40 mM hydrochloric acid and 10 mM triethylamine. Finally, six compounds, including N-formylcytisine (two conformers) ( 1 ), N-acetycytisine (two conformers) ( 2 ), (-)-cytisine ( 3 ), 13-β-hydroxylthermopsine ( 4 ), N-methylcytisine ( 5 ), and thermopsine ( 6 ) were successfully obtained in the two counter-current chromatography modes with the purities over 96.5%. Moreover, we adopted nuclear magnetic resonance and mass spectrometry for structural characterization. Based on the obtained findings, the pH-zone-refining mode was the efficient method to separate quinolyridine alkaloids relative to the traditional mode. 相似文献
106.
Deniss Fedorenko Antons Podjava Arvis Prikulis Vadims Bartkevics 《Journal of separation science》2023,46(11):2201002
A new method for quantitative analysis of several biomarkers and pharmaceutical compounds in wastewater has been developed employing nanoflow liquid chromatography with Orbitrap mass spectrometry. An easy dilute-and-shoot approach has been used for sample preparation with a dilution factor of 5. Improved retention of ionic and highly polar compounds has been achieved by the addition of tetrabutylammonium bromide as an ion pair reagent into the final diluted sample. The new nanoflow liquid chromatography method has demonstrated low matrix effects (70%–111%), high sensitivity in terms of limits of quantification (0.005 to 0.3 μg/L), low injection volume (70 nl) and solvent consumption, and the ability to analyze diverse polar and ionic analytes within one run using a single reversed-phase nanoflow liquid chromatography column. Wastewater samples (n = 116) from the wastewater treatment plants of different cities in Latvia were analyzed using the developed method. The observed concentrations of biomarkers were in line with the literature data. 相似文献
107.
Jie-Ping Fan Ban-Tian He Yi Gao Chun-Fang Xie Hui-Ping Chen Hai-Long Peng 《Journal of separation science》2023,46(8):2200984
Phorbol is a tetracyclic diterpenoid found in Euphorbia tirucalli, Croton tiglium, and Rehmannia glutinosa, and is nuclear of various phorbol esters. The rapid obtaining of phorbol with high purity highly contributes to its application, such as synthesizing phorbol esters with designable side chains and particular therapeutic efficacy. This study introduced a biphasic alcoholysis method for obtaining phorbol from croton oil by using polarity imparity organic solvents in both phases and established a high-speed countercurrent chromatography method for simultaneous separation and purification of phorbol. The optimized operation conditions of biphasic alcoholysis were a reaction time of 91 min, a temperature of 14°C, and a croton oil-methanol ratio of 1:30 (g:ml). The phorbol during the biphasic alcoholysis was 3.2-fold higher in content than that obtained in conventional monophasic alcoholysis. The optimized high-speed countercurrent chromatography method was using the ethyl acetate/n-butyl alcohol/water at 4.7:0.3:5 (v:v:v) with Na2SO4 at 0.36 g/10 ml as the solvent system, using the mobile phase flow rate of 2 ml/min, the revolution of 800 r/min, under which the retention of the stationary phase was achieved at 72.83%. The crystallized phorbol following high-speed countercurrent chromatography was obtained as high purity of 94%. 相似文献
108.
Xiaoxuan Han Ruijie Zhao Yong Tian Yutong Li Xu-Wei Chen Jiping Ma Weiliang Wang Yanfeng Zhang Song Geng Menglin Liu 《Journal of separation science》2023,46(11):2300006
A high-performance liquid chromatography-ultraviolet method was developed for rapidly and simultaneously analyzing novel and typical bisphenols in building materials, including bisphenol S, diphenolic acid, bisphenol F, bisphenol E, bisphenol A, bisphenol B, bisphenol AF, bisphenol AP, bisphenol C, bisphenol FL, bisphenol Z, bisphenol BP, bisphenol M, and bisphenol P. By using a Kromasil 100–5 C18 column, these bisphenols were completely separated in 40 min via gradually increasing the concentration of methanol in the mobile phase from 45 to 80% during the elution process. In particular, this method achieved the synchronous analysis of bisphenol S, diphenolic acid, bisphenol FL, bisphenol BP, and bisphenol M through HPLC, which were difficult to separate and had to be identified and detected through mass spectrometry. The limits of detection of the method ranged from 0.002 to 0.040 mg/L for these 14 bisphenols, with a precision of less than 4.9% (n = 7, c = 0.05 mg/L). The analytical results for five types of building materials (phenolic, epoxy, polycarbonate, polyester, and polysulfone resins) indicated that the proposed method is appropriated for the rapid measurement of bisphenols in real samples. 相似文献
109.
目的 为了研究不同生长期新鲜烟叶中无机阴离子的含量和变换规律,建立了一种固相萃取净化/离子色谱方法测定新鲜烟叶中的7种无机阴离子(F-,Cl-,Br-,NO2-,NO3-,SO42-,PO43-)。方法 样品经0.1 mol/L NaOH水溶液超声提取,萃取液经RP1.0cc固相萃取柱净化后,使用AS11-HC(4 mm×250 mm)色谱柱进行分离,以KOH为流动相,梯度洗脱。 结果 7种无机阴离子在0.10-5.0 μg/mL范围内具有较好的线性(r>0.996),检出限在0.01-0.04 μg/mL之间,定量限在0.04-0.14 μg/mL之间,加标回收率为96.3%~102.1%,相对标准偏差(RSD%)在2.7%~4.8%之间。结论 方法前处理操作简单,7种无机阴离子分离好,检测灵敏准确,可用于不同生长时期新鲜烟叶样品中多种无机阴离子含量的检测分析。 相似文献
110.
Lei Lv Hang Su Shanbin Chen Jinxing He Yuhong Yang Yuan Liu Hanzhu Xing 《Journal of separation science》2023,46(11):2200910
3-Chloro-1,2-propanediol is a common food contaminant, but reports on its determination in biological tissues are lacking. In the present study, a method was developed to detect 3-chloro-1,2-propanediol contents in rat tissues by quick-easy-cheap-effective-rugged-and-safe extraction and gas chromatography-mass spectrometry analysis. Biological samples were extracted with ethyl acetate and purified with adsorbents. The optimized adsorbent for each sample was selected from 4–5 combinations of N-propylethylenediamine, octadecylsilane, graphitized carbon black, strong anion exchange, and florisil. Extracted 3-chloro-1,2-propanediol was derivatized with heptafluorobutyric anhydride and subjected to gas chromatography-mass spectrometry. This method had good linearity (correlation coefficients >0.99) in the range of 2–2000 ng/g for blood, kidney, liver, testis, and brain samples. The limits of detection were under 0.8 ng/g; the limits of quantification were 2 ng/g; the recovery rates were 85%–102%; and the matrix effects were 1.98%–7.67%. This method also had good precision. The dynamic changes in 3-chloro-1,2-propanediol in rats gavaged with 20 mg/kg b.w. for 24 h were detected using this method. The 3-chloro-1,2-propanediol content in each tissue sharply increased to a peak, rapidly decreased within 2 h, and stabilized at 12 h. 3-Chloro-1,2-propanediol persisted in the kidney, testis, and liver 24 h after gavage. 相似文献