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431.
S. A. Muhammed Ali Anwar Mustafa Raduwan Nor Fatina Muchtar Andanastuti Somalu Mahendra Rao 《Journal of Sol-Gel Science and Technology》2018,86(2):493-504
Journal of Sol-Gel Science and Technology - La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) is a perovskite-type oxide that exhibits excellent mixed ionic–electronic conducting properties and is a... 相似文献
432.
Umair Khurshid Saeed Ahmad Hammad Saleem Arslan Hussain LodhI Irfan Pervaiz Mohsin Abbas Khan Haroon Khan Abdulwahab AlamrI Mukhtar AnsarI Marcello LocatellI Muhammad Adeel Arshad Muhammad Asif Wazir Juwairiya Butt Sirajudheen Anwar 《Molecules (Basel, Switzerland)》2022,27(18)
This work was undertaken to explore the phytochemical composition, antioxidant, and enzyme-inhibiting properties of Neurada procumbens L. extracts/fractions of varying polarity (methanol extract and its fractions including n-hexane, chloroform, n-butanol, and aqueous fractions). A preliminary phytochemical study of all extracts/fractions, HPLC-PDA polyphenolic quantification, and GC-MS analysis of the n-hexane fraction were used to identify the phytochemical makeup. Antioxidant (DPPH), enzyme inhibition (against xanthine oxidase, carbonic anhydrase, and urease enzymes), and antibacterial activities against seven bacterial strains were performed for biological investigation. The GC-MS analysis revealed the tentative identification of 22 distinct phytochemicals in the n-hexane fraction, the majority of which belonged to the phenol, flavonoid, sesquiterpenoid, terpene, fatty acid, sterol, and triterpenoid classes of secondary metabolites. HPLC-PDA analysis quantified syringic acid, 3-OH benzoic acid, t-ferullic acid, naringin, and epicatechin in a significant amount. All of the studied extracts/fractions displayed significant antioxidant capability, with methanol extract exhibiting the highest radical-scavenging activity, as measured by an inhibitory percentage of 81.4 ± 0.7 and an IC50 value of 1.3 ± 0.3. For enzyme inhibition experiments, the n-hexane fraction was shown to be highly potent against xanthine oxidase and urease enzymes, with respective IC50 values of 2.3 ± 0.5 and 1.1 ± 0.4 mg/mL. Similarly, the methanol extract demonstrated the strongest activity against the carbonic anhydrase enzyme, with an IC50 value of 2.2 ± 0.4 mg/mL. Moreover, all the studied extracts/fractions presented moderate antibacterial potential against seven bacterial strains. Molecular docking of the five molecules β-amyrin, campesterol, ergosta-4,6,22-trien-3β-ol, stigmasterol, and caryophyllene revealed the interaction of these ligands with the investigated enzyme (xanthine oxidase). The results of the present study suggested that the N. procumbens plant may be evaluated as a possible source of bioactive compounds with multifunctional therapeutic applications. 相似文献
433.
Anwar H Joarder 《International Journal of Mathematical Education in Science & Technology》2013,44(5):772-784
The usual formula for variance depending on rounding off the sample mean lacks precision, especially when computer programs are used for the calculation. The well-known simplification of the total sums of squares does not always give benefit. Since the variance of two observations is easily calculated without the use of a sample mean, and the variance of a sample of n observations is the average of the variances of observations based on n(n-1)/2 distinct subsets of units of size 2 from the sample, it is argued that this sense of pairing may result in precision. Some other forms of variance are presented which provide some insight into it. The contribution of a new observation of variance is highlighted, which is important in sequential sampling. Notions are illustrated with examples. 相似文献
434.
Syed Raza Shah Zarbad Shah Mohammed Khiat Sobia A. Halim Ajmal Khan Javid Hussain Rene Csuk Muhammad U. Anwar Ahmed Al-Harrasi 《应用有机金属化学》2020,34(10):e5842
The coordination chemistry of 1,10-phenanthroline (phen) and sodium 1,3-benzothiazole-2-thiolate (SBT) with selected s-block elements has been investigated. Four metal complexes were prepared and their structures were characterized using a variety of analytical techniques including infrared, UV–visible, 1H NMR and 13C NMR spectroscopies, elemental analysis, mass spectrometry and single-crystal X-ray diffraction. The reactions of phen and SBT with M(X)n (M = K(I), Cs(I), Mg(II), Sr(II); X = OH−, CO3−, Cl−; n = 1, 2) in MeOH–H2O yielded one-dimensional chains of both potassium [K2(phen)2(BT)2(H2O)4]n ( 1 ) and caesium [Cs(phen)(BS)(H2O)]n ( 2 ) (where BT = 1,3-benzthiazole-2-thiolate and BS = 1,3-benzthiazole-2-sulfinothiolate) and mononuclear complexes of both magnesium {[Mg(phen)(H2O)4](BT)2·phen} ( 3 ) and strontium {[Sr(phen)2(H2O)4](BT)2} ( 4 ). In these complexes, phen binds via an N,N′ chelate pocket, while the monoanonic BT− ligands either coordinate in a bidentate fashion (in the case of 1 ) or remain uncoordinated (in the case of 3 and 4 ). In complex 2 , SBT ligand was oxidized in situ into a new BS ligand. The sulfinothiolate oxygen atoms in BS coordinate with caesium in a tridentate fashion. Complexes 1 – 4 were evaluated against urease for enzyme inhibition. The complexes displayed significant inhibition with IC50 values in the range 10.8–45.8 μM. In order to examine the structure–activity relationship, the complexes were docked at the active site of urease. Docking results clearly demonstrate the binding of each complex within the active site of the enzyme. 相似文献
435.
Bassam Oudh Aljohny Zubair Ahmad Sher Ali Shah Yasir Anwar Shahid Ali Khan 《应用有机金属化学》2020,34(11):e5892
Cellulose acetate (CA), and CA blended with Nicotiana tabacum ash (ACA) membranes have synthesized and fabricated with zero-valent Fe NPs (ZVI) and named as CA@Fe0 and ACA@Fe0. The as-synthesized membranes were inspected for the removal and detoxification of toxic organic pollutants. Comparative studies of CA@Fe0 and ACA@Fe0 NPs were investigated for five model pollutants, such as 4-nitrophenol (4NP), methyl orange (MO), Congo red (CR), methylene blue (MB), and bromocresol green (BCG). The kinetic model indicated that the apparent rate constant Kapp value of ACA@Fe0 was highest for all model pollutants compared to CA@Fe0 NPs. The Kapp value is derived from pseudo-first-order kinetics. The Kapp value of MO discoloration was 8.17 × 10−1 min−1 with ACA@Fe0 which is highest than CA@Fe0 (3.08 × 10−1 min−1). The turnover frequency (TOF) was highest for ACA@Fe0 for all the pollutants compared to CA@Fe0 and the highest TOF value was found for CR dye with ACA@Fe0 which is 0.523 h−1. Both the membranes also showed promising antibacterial activity against Salmonella typhi. Furthermore, CA, ACA membrane and CA@Fe0 and ACA@Fe0 NPs were characterized through FESEM, EDS, XRD, FTIR and TGA analysis. 相似文献
436.
Zahoor Ahmad Parray Faizan Ahmad Md. Imtaiyaz Hassan Anwar Ahmed Fahad N. Almajhdi Ajamaluddin Malik Tajamul Hussain Asimul Islam 《Molecules (Basel, Switzerland)》2021,26(9)
The intracellular environment is overcrowded with a range of molecules (small and large), all of which influence protein conformation. As a result, understanding how proteins fold and stay functional in such crowded conditions is essential. Several in vitro experiments have looked into the effects of macromolecular crowding on different proteins. However, there are hardly any reports regarding small molecular crowders used alone and in mixtures to observe their effects on the structure and stability of the proteins, which mimics of the cellular conditions. Here we investigate the effect of different mixtures of crowders, ethylene glycol (EG) and its polymer polyethylene glycol (PEG 400 Da) on the structural and thermal stability of myoglobin (Mb). Our results show that monomer (EG) has no significant effect on the structure of Mb, while the polymer disrupts its structure and decreases its stability. Conversely, the additive effect of crowders showed structural refolding of the protein to some extent. Moreover, the calorimetric binding studies of the protein showed very weak interactions with the mixture of crowders. Usually, we can assume that soft interactions induce structural perturbations while exclusion volume effects stabilize the protein structure; therefore, we hypothesize that under in vivo crowded conditions, both phenomena occur and maintain the stability and function of proteins. 相似文献
437.
Bimal B. Chakraborty Siddique Anwar Saurav Das Satya B. Paul Golam Mohiuddin Joydip De 《Liquid crystals》2018,45(11):1644-1653
In this work, hydrogen-bonded liquid crystal exhibiting phase dependent fluorescence has been reported. The H-bonded materials were prepared using pyridenyl benzothiazole and alkoxy benzoic acid as H-bond acceptor and donor respectively. The formation of the target materials was confirmed via different spectroscopic technique and their mesogenic behaviour has been studied through polarising optical microscope, differential scanning calorimetry and 2D-X-ray diffraction. The H-bonded mesogenic material showed aggregation dependent fluorescence switching when subjected to transformation from isotropic-nematic-crystalline phase sequence. Computational studies were performed to probe into fluorescence switching behaviour of the mesogenic material. 相似文献
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