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191.
Navid Nasirizadeh Hamid R. Zare Ali R. Fakhari Hamid Ahmar Mohammad R. Ahmadzadeh Amin Naeimi 《Journal of Solid State Electrochemistry》2011,15(11-12):2683-2693
In this study, an oxadiazole multi-wall carbon nanotube-modified glassy carbon electrode (OMWCNT?GCE) was used as a highly sensitive electrochemical sensor for hydrazine determination. The surface charge transfer rate constant, k s, and the charge transfer coefficient, ??, for electron transfer between GCE and electrodeposited oxadiazole were calculated as 19.4?±?0.5?s?1 and 0.51, respectively at pH?=?7.0. The obtained results indicate that hydrazine peak potential at OMWCNT?GCE shifted for 14, 109, and 136?mV to negative values as compared with oxadiazole-modified GCE, MWCNT?GCE, and activated GCE surface, respectively. The electron transfer coefficient, ??, and the heterogeneous rate constant, k??, for the oxidation of hydrazine at OMWCNT?GCE were also determined by cyclic voltammetry measurements. Two linear dynamic ranges of 0.6 to 10.0???M and 10.0 to 400.0???M and detection limit of 0.17???M for hydrazine determination were evaluated using differential pulse voltammetry. In addition, OMWCNT?GCE was shown to be successfully applied to determine hydrazine in various water samples. 相似文献
192.
Yahayu MA Rahmani M Hashim NM Amin MA Ee GC Sukari MA Akim A 《Molecules (Basel, Switzerland)》2011,16(6):4401-4407
Extraction and chromatographic separation of the extracts of dried stem barks of Glycosmis macrantha lead to isolation of two new acridone alkaloids, macranthanine and 7-hydroxynoracronycine, and a known acridone, atalaphyllidine. The structures of these alkaloids were determined by detailed spectral analysis and also by comparison with reported data. 相似文献
193.
Castillo-Martínez E Bieringer M Shafi SP Cranswick LM Alario-Franco MÁ 《Journal of the American Chemical Society》2011,133(22):8552-8563
A novel ScVO(3) perovskite phase has been synthesized at 8 GPa and 1073 K from the cation-disordered bixbyite-type ScVO(3). The new perovskite has orthorhombic symmetry at room temperature, space group Pnma, and lattice parameters a = 5.4006(2) ?, b = 7.5011(2) ?, and c = 5.0706(1) ? with Sc(3+) and V(3+) ions fully ordered on the A and B sites of the perovskite cell. The vanadium oxygen octahedra [V-O(6)] display cooperative Jahn-Teller (JT) type distortions, with predominance of the tetragonal Q(3) over the orthorhombic Q(2) JT modes. The orthorhombic perovskite shows Arrhenius-type electrical conductivity and undergoes a transition to triclinic symmetry space group P-1 close to 90 K. Below 60 K, the magnetic moments of the 4 nonequivalent vanadium ions undergo magnetic long-range ordering, resulting in a magnetic superstructure of the perovskite cell with propagation vector (0.5, 0, 0.5). The magnetic moments are confined to the xz plane and establish a close to zigzag antiferromagnetic mode. 相似文献
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196.
Bashir M. S. Ali S. Shahzadi S. Shahid M. 《Russian Journal of General Chemistry》2015,85(6):1532-1537
Russian Journal of General Chemistry - The new organotin(IV) complexes have been synthesized by the reaction of l-lysine monohydrate with CS2 and R2SnCl2/R3SnCl. The organotin(IV) complexes and the... 相似文献
197.
Jahangeer Patujo Amin Badshah Raja Azadar Hussain Muhammad Nawaz Tahir Shaista Tahir Muhammad Khawar Rauf 《中国化学会会志》2015,62(11):1020-1027
In the present work new nitro substituted thioureas, and their copper complexes have been synthesized and characterized by FTIR and multinuclear NMR techniques. Some of the compounds namely 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐1), 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐2) and 1‐benzoyl‐3‐(2‐methoxy‐4‐nitrophenyl) thiourea (A‐2) have also been characterized by single crystal XRD. All the synthesized compounds have been screened for DNA binding potencies (using cyclic voltametry, UV‐vis spectroscopy) and free radical scavanging activities. 相似文献
198.
Rapid preparative isolation of erythrocentaurin from Enicostemma littorale by medium‐pressure liquid chromatography,its estimation by high‐pressure thin‐layer chromatography,and its α‐amylase inhibitory activity 下载免费PDF全文
Naila Hassan Javed Ahamad Saima Amin Mohd Mujeeb Showkat R. Mir 《Journal of separation science》2015,38(4):592-598
Erythrocentaurin is a relatively simple natural product present among the members of Gentianaceae. A preparative method for the isolation of erythrocentaurin from the ethyl acetate fraction of Enicostemma littorale using medium‐pressure liquid chromatography has been reported. The method consisted of a simple step gradient from 10 to 20% ethyl acetate in n‐hexane. Using a 70 × 460 mm Si60 column, this method is capable of processing 20 g of material in <3 h (purity ≈ 97%). The recovery of erythrocentaurin was 87.77%. Estimation of erythrocentaurin in extracts and fractions based on high‐pressure thin‐layer chromatography was carried out on silica gel 60 F254 plates with toluene/ethyl acetate/formic acid (80:18:2 v/v/v) as the mobile phase. The densitometric analysis was performed at 230 nm. A well‐separated compact band of erythrocentaurin appeared at Rf 0.54 ± 0.04. The analytical method showed good linearity in the concentration range of 200–1500 ng/band with a correlation coefficient of 0.99417. The limits of detection and quantification were found to be ≈60 and ≈180 ng/band, respectively. Erythrocentaurin exhibited a concentration‐dependent α‐amylase inhibition (IC50 1.67 ± 0.28 mg/mL). The outcome of the study should be considered for pharmacokinetic and biotransformation studies involving E. littorale. 相似文献
199.
Mohammad Amin Almasi Seyed Mohammad Hosseyni-Dehabadi Mehdi Aghapour-ojaghkandi 《Applied biochemistry and biotechnology》2014,173(7):1836-1848
To diminish the time required for some diagnostic assays including polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP; due to mainly DNA extraction step) and also triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) into a minimum level, an innovative immunocapture LAMP (IC-LAMP) and immunocapture PCR (IC-PCR) protocol on the basis of beet curly top virus (BCTV) genome was used and optimized. TAS-ELISA was employed first to validate the existence of the virus. All six IC-LAMP primers (i.e. forward outer primer (F3), backward outer primer (B3), forward inner primer (FIP), backward inner primer (BIP), loop forward (LF) and loop backward (LB)) together with IC-PCR primers were designed on the basis of the replication-associated protein (rep) gene (GenBank accession AF379637.1) of BCTV genome. Also, a novel colorimetric IC-LAMP assay for rapid and easy detection of BCTV was developed here, its potential compared with TAS-ELISA and IC-PCR assays. The method, on the whole, had the following advantages over the two mentioned procedures: (i) fascinatingly, no need of DNA extraction; (ii) no requirement of expensive and sophisticated tools for amplification and detection; (iii) no post-amplification treatment of the amplicons and (iv) a flexible and easy detection approach, which is visually detected by naked eyes using diverse visual dyes. 相似文献
200.
A. M. Amin A. A. Gouda R. El-Sheikh U. Seddik H. Hussien 《Journal of Radioanalytical and Nuclear Chemistry》2009,280(3):589-598
The present study is performed to compare the electrophilic substitution radioiodination reaction of two non-steroidal anti-inflammatory
drugs namely, Piroxicam (Pirox) and Meloxicam (Melox) with 125I where both chloramine-T (CAT) and iodogen were used as oxidizing agents. The factors affecting the percent of radiochemical
yields such as drug concentration, pH of the reaction mixtures, different oxidizing agents, reaction time, temperature and
different organic media were studied to optimize the conditions for labeling of Pirox and Melox and to obtain high radiochemical
yields. The maximum radiochemical yield of 125I-Piroxicam (125I-Pirox) was 94% using 3.7 MBq of Na125I, 0.4 mM of Pirox as substrate, 3.6 mM of chloramine-T (CAT) as oxidizing agent in acetone at neutral pH = 7 and at 60 °C
within 20 min where the maximum radiochemical yield of 125I-Melox was 92% using 0.7 mM of Melox as substrate, 0.62 mM of iodogen as oxidizing agent in acetone at neutral pH = 7 and
at 25 °C within 30 min. The radiochemical yields were determined by TLC and high-pressure liquid chromatography (HPLC). Tracers
showed good localization in inflamed muscle either septic or sterile. The collected data indicates that Pirox and Melox can
be used as antiinflammatory imaging agents at 24 and 2 h post injection, respectively. 相似文献