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131.
Abstract: We demonstrate that wax-embedded models of tissue-engineered oral mucosa can be effectively dewaxed using xylene for Raman spectroscopic analysis. Tissue sections of 20 μm thickness were cut and mounted onto glass slides. Sections were placed in xylene for increasing lengths from 2 to 45 min. Acquired Raman spectra revealed the wax contribution in the fingerprint region until 28-min treatment in xylene. Good quality and wax-free spectra were recorded at 30, 35, 40, and 45 min in xylene with no significant differences among them. It is essential to collect uncontaminated Raman spectra in order to achieve authentic results because the fingerprint region of biological tissues holds extremely vital information that is of diagnostic significance in cancer. 相似文献
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以最新发布的ENDF/BVII.1评价库为基础, 使用SIGACE程序将低温ACE格式中子截面文件加工成较高温度的ACE格式文件, 生成了一个与温度相关的中子截面文档。 为校核截面数据, 选取ICT、 标准CANDU组件燃料温度反应性系数、 LWR栅格多普勒系数以及SEFOR基准题对SIGACE加工的核数据进行了验证。 基准题计算结果均与参考值符合较好, 表明SIGACE生成的高温度ACE格式截面数据可用于反应堆相关中子学参数的计算。 Based on the recently released ENDF/B-VII.1 library, high temperature neutron cross section files are generated through SIGACE code using low temperature ACE format files. To verify the processed ACE file of SIGACE, benchmark calculations are performed in this paper. The calculated results of selected ICT, standard CANDU assembly, LWR Doppler coefficient and SEFOR benchmarks are well conformed with reference value, which indicates that high temperature ACE files processed by SIGACE can be used in related neutronics calculations. 相似文献
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135.
Tong-Tong Feng Yi-Sheng Yang Zhi-Qiang Zhou Mian Dai Hong-Yu Bi 《Natural product research》2019,33(9):1269-1276
Two new noroleanane-type triterpenoid saponins, 3β,20α,24-trihydroxy-29-norolean-12-en-28-oic acid 24-O-β-L-fucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranoside (1) and 3β,20α,24-trihydroxy-29-norolean-12-en-28-oic acid 24-O-β-D-glucopyranosyl-(1→2)-[α-L-arabinopyranosyl-(1→3)]-β-D-glucopyranoside (2) were isolated from the stems of Stauntonia chinensis DC., together with three known compounds, brachyantheraoside B2 (3), eupteleasaponin Ⅷ (4) and fargoside B (5). Their structures were elucidated by spectroscopic and chemical methods. The cytotoxic activities of compounds 1 and 2 were evaluated against five human tumor cell lines (HCT-116, HepG2, BGC-823, NCI-H1650, and A2780). Compounds 1 and 2 showed moderate cytotoxic activities toward the tested cell lines with IC50 values ranging from 12.71 to 32.04 μM. 相似文献
136.
An efficient and convenient method for the synthesis of various substituted pyrano[3,2-c]chromene-2,5-diones was developed via the I2-promoted tandem cyclization of commercially available aryl methyl ketones and 4-hydroxycoumarins. Preliminary mechanism studies indicated that the reaction involved a consecutive iodination/Kornblum oxidation/annulation process. HI produced in the I2-DMSO system acted as an important promoter, accelerating the annulation protocol. 相似文献
137.
Muhammad Yaseen Zahid Farooq Mian H. R. Mahmood Sheikh Asrar Ahmad Shahbaz Nazir Khalid Mahmood Anjum Syed Ali Raza Naqvi 《Journal of heterocyclic chemistry》2019,56(5):1520-1529
A new convenient solid–liquid condensation reaction procedure for the synthesis of novel asymmetric and symmetric meso‐tetraarylporphyrin and metalloporphyrin Schiff bases is reported. The condensation reaction between β‐formyl porphyrin or metalloporphyrins and aromatic amines was carried out at solid–liquid interface by using neutral alumina powder as a solid support for β‐formyl porphyrin or metalloporphyrins and absolute ethanol as the carrier solvent for aromatic amines. Six different asymmetric porphyrin/metalloporphyrin Schiff bases were synthesized via solid–liquid interface reaction methodology. The same solid–liquid synthetic methodology was applied for the synthesis of six novel symmetric Schiff base porphyrin/metalloporphyrin dimers. The comparison of UV–visible spectra of porphyrin Schiff base monomers and dimers revealed that some degree of electronic perturbation has occurred upon dimerization as the Soret bands of the monomers underwent peak broadening along with red shifts. Column chromatography and crystallization were used to purify the compounds. Fourier transform infrared, UV–visible, elemental analysis, 1H NMR, and mass spectrometry were used to characterize the newly synthesized compounds. 相似文献
138.
Yongda Huang Yuhan Yang Hongyun Hu Mian Xu Huan Liu Xian Li Xinye Wang Hong Yao 《Proceedings of the Combustion Institute》2019,37(3):2951-2957
Arsenic is easily evaporated during coal combustion, which not only raises serious environmental concerns but also results in the deactivation of catalyst in selective catalytic reduction (SCR) systems. It is a promising method to use sorbents for the capture of arsenic vapors (As2O3(g)) before As-containing flue gas entering SCR catalyst. However, arsenic has a strong affinity with sulfur in coal and SO2 in the coal combustion flue gas strongly suppresses As2O3(g) capture by typical Ca/Fe-based sorbents. This study estimated the selective capture of As2O3(g) by γ-Al2O3 and the effects of SO2 and NO on the arsenic adsorption were investigated. The results showed that As2O3(g) adsorption over γ-Al2O3 was effectively conducted at temperatures ranging from 300 to 400 °C. In the reacted γ-Al2O3, arsenic was predominantly in the form of As3+ through reactions with Al-O bonds and positive charged alumina ions. SO2 was slightly adsorbed on γ-Al2O3, which had a limited effect on arsenic adsorption. The adsorption of SO2 on γ-Al2O3 mainly occurred on the sites of hydroxyl groups (Al-OH) and few adsorbed SO2 was bound with positive charged alumina ions. NO was catalytically oxidized by γ-Al2O3 and released as NO2. Nevertheless, NO competed with As2O3(g) to adhere to positive charged alumina ions and strongly suppressed arsenic adsorption over γ-Al2O3. Fortunately, in the presence of SO2, NO was mostly transformed into intermediate (-SO3NO) at the sites of Al-OH on γ-Al2O3. As a result, the adverse effect of NO on the adsorption of As2O3(g) was weakened. 相似文献
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140.
用循环伏安法首次在金电极上制成一种新的类普鲁士-亚换氰化锌膜.研究发现,膜的形成不仅与新生成的Fe(CN)4-6和Zn(Ⅱ)有关,同时也受溶液中共存的其它离子的品种和浓度的影响.膜氧化时解离,溶解;还原时受膜厚度不同的影响呈不同的电极反应过程.现已提出了可能的反应机理.并利用亚铁氰化锌膜的特别性质,分析测定Zn(Ⅱ)达1×10-7mol/L,并也定量测定了K+. 相似文献