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排序方式: 共有1163条查询结果,搜索用时 203 毫秒
101.
Novel lanthanide coordination compounds with ciprofloxacin (CPFX), including eleven complexes Ln(CPFX)2Cl(H2O), (Ln=Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb; n = 7, 8, 9) and crystalline [Ce(CPFX)2 (H2O)4] Cl (H2O)3.25 (C2H5‐OH)0.25, were synthesized. The crystal is of triclinic space group Pi with a= 1.3865(2) nm, b = 1.3899(3) nm, c = 1.6505(2) nm, a = 92.73(1)°, β= 114.39(1)°, γ=115.55 (1)°, Z = 2 and R = 0.0449. FT‐IR, electronic spectroscopy and X‐ray diffraction were employed to show that the lanthanide ion, which displays an eight‐coordinate structure, is chelated by 3‐carboxyl and 4‐keto oxygen donors of CPFX and two six‐membered chelate rings are formed. Test of in vitro antibacterial activity against E. coli, P. aeruginosa and S. aureus indicated that the in vitro antibacterial activity of the ligand can be improved by complexation with Ce(III). 相似文献
102.
Islam Ullah Khan Tehseen Aman Muhammad Asif Iqbal Asrar Ahmad Kazi 《Mikrochimica acta》2000,134(1-2):27-31
Fluoxetine hydrochloride reacts with benzoyl peroxide and potassium iodide, after heating for 1 min at 30 °C, to give a blue
colour having maximum absorbance at 570 nm. The reaction is selective for fluoxetine with 0.01 mg/mL as visual limit of quantitation
and provides a basis for a new spectrophotometric determination. The colour reaction obeys Beer’s law from 0.1 mg/10 mL to
2.0 mg/10 mL of fluoxetine and the relative standard deviation is 0.68%. The qualitative assessment of tolerable amounts of
other drugs is also studied.
Received September 21, 1998. Revision September 10, 1999. 相似文献
103.
研究了桂枝和桂皮醛对环丙沙星在小鼠体内分布的影响,并基于此探讨了桂枝作为引药使用的作用机制.实验中将小鼠分为三组,分别灌胃生理盐水、桂枝(50gkg-1)和桂皮醛(0.25mLkg-1),然后对三组小鼠尾静脉注射环丙沙星(20mgkg-1),并以荧光法测定不同时间点小鼠体内各组织中环丙沙星的浓度.结果显示桂枝、桂皮醛均促进了环丙沙星在四肢的分布,桂枝与桂皮醛组相对于生理盐水组可将环丙沙星在四肢的含量提高约40%~200%,证实了桂枝引药到达肢节的作用.桂枝与桂皮醛组对环丙沙星分布情况的影响没有显著性差异,说明桂皮醛很可能是发挥桂枝引药作用的主要物质. 相似文献
104.
Stacy P. Ali 《Journal of carbohydrate chemistry》2013,32(4):185-196
The order of reactivity of OH and NH groups of glucosamine hydrochloride (GlcNH2.HCl) and N-acetyl glucosamine (GlcNAc) toward benzylation with NaH/BnBr in DMF was investigated. For GlcNH2.HCl, benzyl groups were introduced in the order of N-Bn > N-Bn2 > 1-O-Bn > 6-O-Bn > 4-O-Bn > 3-O-Bn; for GlcNAc, benzyl groups were introduced in the order of 1-O-Bn > 6-O-Bn > 4-O-Bn > 3-O-Bn > N-Bn. A range of partially benzylated 2-N,N′-dibenzyl glucopyranosides and GlcNAc derivatives were obtained in a single step. 相似文献
105.
Joana Sousa Gilberto Alves Ana Fortuna Angelina Pena Celeste Lino Amílcar Falcão 《Biomedical chromatography : BMC》2011,25(5):535-541
A simple and fast liquid chromatographic method coupled with fluorescence detection (LC‐FD) is reported, for the first time, for the simultaneous quantification of norfloxacin (NOR), ciprofloxacin (CIP) and lomefloxacin (LOM) in human plasma, using levofloxacin as internal standard (IS). Sample preparation consists of a single‐step precipitation of plasma proteins followed by vortex‐mixing and centrifugation. Chromatographic separation was achieved within 7 min on a reversed‐phase C18 column with a mobile phase consisting of 0.1% aqueous formic acid (pH = 3.0, triethylamine)–methanol (82:18, v/v) pumped isocratically at 1.2 mL/min. The detector was set at excitation/emission wavelengths of 278/450 nm. Calibration curves were linear (r2 ≥ 0.994) in the range of 0.02–5.0 µg/mL, and the limit of quantification was established at 0.02 µg/mL for all analytes (NOR, CIP and LOM). The overall precision did not exceed 8.19% and accuracy was within ±10.91%. NOR, CIP and LOM were extracted from human plasma with an overall mean recovery ranged from 90.1 to 111.5%. No interferences were observed at the retention times of the analytes and IS. This novel LC‐FD method enables the reliable determination of NOR, CIP and LOM in a single chromatographic run, which may be suitable to support human pharmacokinetic‐based studies with those antimicrobial agents. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
106.
107.
In this work, different mass percent ratios of CoFe2O4 coupled g-C3N4 (w%-CoFe2O4/g-C3N4, CFO/CN) nanocomposites were integrated through a hydrothermal process for the sonocatalytic eradication of tetracycline hydrochloride (TCH) from aqueous media. The prepared sonocatalysts were subjected to various techniques to investigate their morphology, crystallinity, ultrasound wave capturing activity and charge conductivity. From the investigated activity of the composite materials, it has been registered that the best sonocatalytic degradation efficiency of 26.71 % in 10 min was delivered when the amount of CoFe2O4 was 25% in the nanocomposite. The delivered efficiency was higher than that of bare CoFe2O4 and g-C3N4. This enriched sonocatalytic efficiency was credited to the accelerated charge transfer and separation of e−-h+ pair through the S-scheme heterojunctional interface. The trapping experiments confirmed that all the three species i.e. •OH, h+ and •O2− were involved in the eradication of antibiotics. A strong interaction was shown up between CoFe2O4 and g-C3N4 in the FTIR study to support charge transfer as confirmed from the photoluminescence and photocurrent analysis of the samples. This work will provide an easy approach for fabricating highly efficient low-cost magnetic sonocatalysts for the eradication of hazardous materials present in our environment. 相似文献
108.
Inversion twinning in a second polymorph of the hydrochloride salt of the recreational drug ethylone
T. Stanley Cameron J. Stuart Grossert Chad R. Maheux Idralyn Q. Alarcon Catherine R. Copeland Anthony Linden 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(4):266-270
A second polymorph of the hydrochloride salt of the recreational drug ethylone, C12H16NO3+·Cl−, is reported [systematic name: (±)‐2‐ethylammonio‐1‐(3,4‐methylenedioxyphenyl)propane‐1‐one chloride]. This polymorph, denoted form (A), appears in crystallizations performed above 308 K. The originally reported form (B) [Wood et al. (2015). Acta Cryst. C 71 , 32–38] crystallizes preferentially at room temperature. The conformations of the cations in the two forms differ by a 180° rotation about the C—C bond linking the side chain to the aromatic ring. Hydrogen bonding links the cations and anions in both forms into similar extended chains in which any one chain contains only a single enantiomer of the chiral cation, but the packing of the ions is different. In form (A), the aromatic rings of adjacent chains interleave, but pack equally well if neighbouring chains contain the same or opposite enantiomorph of the cation. The consequence of this is then near perfect inversion twinning in the structure. In form (B), neighbouring chains are always inverted, leading to a centrosymmetric space group. The question as to why the polymorphs crystallize at slightly different temperatures has been examined by density functional theory (DFT) and lattice energy calculations and a consideration of packing compactness. The free energy (ΔG) of the crystal lattice for polymorph (A) lies some 52 kJ mol−1 above that of polymorph (B). 相似文献
109.
110.