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111.
112.
Konstantinos Kostelenos Feidias Bairamis Nikolaos Karamoschos Dr. Lamprini Sygellou Prof. Konstantinos S. Andrikopoulos Prof. Ioannis Konstantinou Prof. Dimitrios Tasis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(63):15806-15814
Among the various organic pollutants and industrial chemicals, 4-nitrophenol has been one of the most monitored substances in aqueous environments, due to its enhanced solubility in such systems. This research reports for the first time the microwave-assisted synthesis of CdS/carbon/MoSx hybrids and the subsequent utilization of such systems as photocatalysts for 4-nitrophenol degradation. The hybrids demonstrated a variable photocatalytic activity, by using a variety of organic substances as precursors for the solvothermal carbonization step. By using ascorbic acid as precursor, the corresponding ternary composite exhibited excellent photocatalytic activity, with the 4-nitrophenol concentration been almost quantitatively decayed within 45 min of irradiation. This could be ascribed due to the generation of a high population of heterojunctions as well as the chemical speciation of Mo-based nanostructures. Such ternary hybrids may be utilized as potential photocatalytic systems in processes, where removal of toxic water-soluble substances is the key issue. 相似文献
113.
George Agelis Panagiota Roumelioti Amalia Resvani Serdar Durdagi Maria-Eleni Androutsou Konstantinos Kelaidonis Demetrios Vlahakos Thomas Mavromoustakos John Matsoukas 《Journal of computer-aided molecular design》2010,24(9):749-758
A new 1,5 disubstituted imidazole AT1 Angiotensin II (AII) receptor antagonist related to losartan with reversion of butyl and hydroxymethyl groups at the 2-,
5-positions of the imidazole ring was synthesized and evaluated for its antagonist activity (V8). In vitro results indicated that the reorientation of butyl and hydroxymethyl groups on the imidazole template of losartan
retained high binding affinity to the AT1 receptor concluding that the spacing of the substituents at the 2,5- positions is of primary importance. The docking studies
are confirmed by binding assay results which clearly show a comparable binding score of the designed compound V8 with that of the prototype losartan. An efficient, regioselective and cost effective synthesis renders the new compound as
an attractive candidate for advanced toxicological evaluation and a drug against hypertension. 相似文献
114.
Konstantinos A. Kouremenos James Pitt Philip J. Marriott 《Journal of chromatography. A》2010,1217(1):104-111
Comprehensive two-dimensional gas chromatography (GC × GC) time-of-flight mass spectrometry (ToFMS) was applied to the analysis of urinary organic acids from patients with inborn errors of metabolism. Abnormal profiles were obtained from all five patients studied. Methylmalonic academia and deficiencies of 3-methylcrotonyl-CoA carboxylase and medium chain acyl-CoA dehydrogenase gave diagnostic profiles while deficiencies of very long chain acyl-CoA dehydrogenase and mitochondrial 3-hydroxy-3-methylglutaryl CoA synthase gave profiles with significant increases in dicarboxylic acids suggestive of these disorders. The superior resolving power of GC × GC with ToFMS detection was useful in separating isomeric organic acids that were not resolved using one-dimensional GC. A novel urinary metabolite, crotonyl glycine, was also discovered in the mitochondrial 3-hydroxy-3-methylglutaryl CoA synthase sample which may be a useful specific diagnostic marker for this disorder. The quantitative aspects of GC × GC were investigated using stable isotope dilution analyses of glutaric, glyceric, orotic, 4-hydroxybutyric acids and 3-methylcrotonylglycine. Correlation coefficients for linear calibrations of the analytes ranged from 0.9805 to 0.9993 (R2) and analytical recoveries from 77% to 99%. This study illustrates the potential of GC × GC–ToFMS for the diagnosis of organic acidurias and detailed analysis of the complex profiles that are often associated with these disorders. 相似文献
115.
Time dependency and irreversibility of water desorption by drinking-water treatment residuals: implications for sorption mechanisms 总被引:1,自引:0,他引:1
Drinking-water treatment residuals (WTRs) are being evaluated as cost-effective sorption media for use in environmental remediation. Data from previous work have suggested that intraparticle phosphorus (P) diffusion into micropores is the rate-limiting mechanism of P sorption by WTRs. We used isothermal thermogravimetric analysis (TG) to study water desorption/resorption dynamics as they relate to steric diffusion rate limitations for prospective sorbates. Results showed that air-dried WTR particles contain significant amounts of water. Only about 40% of water desorbed isothermally (70 degrees C) for 10 h was readsorbed when particles were reexposed to ambient temperature and moisture conditions. This hysteresis related closely with time dependency of water loss, suggesting steric diffusional hindrance of water re-adsorption by meso- and micropores. The irreversibly desorbed water may be the component requiring increased kinetic energy to overcome diffusional resistance. Another possible factor in irreversibility could be pore shrinkage. Samples incubated for 12 months at 70 degrees C prior to TG analysis showed no hysteresis at 70 degrees C. Isothermal water losses with time fit well (r2 = 0.95) the diffusion model of Kabai. These results are consistent with an aqueous pore network that would account for high phosphorus sorption capacity and hysteresis that has been recently documented for WTRs. 相似文献
116.
Makris KG Hudock J Christodoulides DN Stegeman GI Manela O Segev M 《Optics letters》2006,31(18):2774-2776
We study theoretically nonlinear surface waves in optical lattices and show that solitons can exist at the heterointerface between two different semi-infinite 1D waveguide arrays, as well as at the boundaries of a 2D nonlinear lattice. The existence and properties of these surface soliton solutions are investigated in detail. 相似文献
117.
Ioannis Konstantinos Argyros José Antonio Ezquerro Miguel Ángel Hernández-Verón Young Ik Kim Ángel Alberto Magreñán 《Mathematical Methods in the Applied Sciences》2020,43(14):8042-8050
In this paper, we propose a center Lipschitz condition for the second derivative together with the use of restricted domains in order to improve the starting points for Newton's method when compared with previous results. Moreover, we present some numerical examples validating the theoretical results. 相似文献
118.
We provide an algorithm with constant running time that given a weighted tournament , distinguishes with high probability of success between the cases that can be represented by a Bradley–Terry model, or cannot even be approximated by one. The same algorithm tests whether the corresponding Markov chain is reversible. 相似文献
119.
Ring closing metathesis (RCM) of 8,9-diallylpurines or 9-butenyl-8-vinylpurines with the Grubbs 2nd generation catalyst resulted in fused 6,9- or 8,9-dihydropyrido[e]purines, respectively. The 8,9-dialkenylpurines were prepared from 8-bromopurines after 9-alkenylation and subsequent Stille coupling at C-8 with alkenylstannanes in the presence of Pd(PPh3)4 or Pd(PPh3)2Cl2. 相似文献
120.
Konstantinos D. Papavasileiou Theodora D. Tzima Yiannis Sanakis Dr. Vasilios S. Melissas Dr. 《Chemphyschem》2007,8(18):2595-2602
The present study employs a complete theoretical investigation, at the B3LYP/cc‐pVTZ level of theory, of the interactions between the tyrosyl radical and nitric oxide, exploring in detail the nitrotyrosine formation radical mechanism. Tyrosyl radicals play an essential role in catalytic reactions of numerous enzymes and biological systems have regulated appropriate mechanisms for their formation. Nitric oxide reacts with the tyrosyl radical and affords a weak intermediate complex which, through a sequence of non‐ionic water catalyzed and biologically feasible intermediate reactions, yields the iminoxyl radical. The iminoxyl radical further combines with hydroxyl radical, a species present in pathophysiological conditions, to yield nitrotyrosine. 相似文献