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41.
Sabrina Aufar Salma Cuong M.Q. Le Dong Woo Kim Xuan Thang Cao Yeon Tae Jeong 《Molecular Crystals and Liquid Crystals》2018,662(1):188-196
ABSTRACTA well-defined amphiphilic block copolymer, poly (ethylene oxide)-b-(poly (furfuryl methacrylate) (PEO-b-PFMA) was prepared by single electron transfer living radical polymerization using tris(dimethylamino)ethyl amine (Me6TREN) as a ligand. The block copolymer formed sub-100 nm micelles in water with PEO as a shell and PFMA as a core. Diels–Alder click type reaction was employed to form core-crosslinked micelles using a diselenide-containing crosslinker without any catalyst. The block copolymer and micelles were characterized by gel permeation chromatography, nuclear magnetic resonance, Fourier-transform infrared spectroscopy, dynamic light scattering analysis and transmission electron microscopy. The stability of core-crosslinked micelles under reductive-oxidative condition was also investigated. The diselenide crosslinked micelles displayed good stability against extensive dilution but decomposed under the presence of hydrogen peroxide or glutathione. The redox responsive core-crosslinked micelles can be a promising carrier for drug delivery applications. 相似文献
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We explain how the field of logarithmic‐exponential series constructed in 20 and 21 embeds as an exponential field in any field of exponential‐logarithmic series constructed in 9 , 6 , and 13 . On the other hand, we explain why no field of exponential‐logarithmic series embeds in the field of logarithmic‐exponential series. This clarifies why the two constructions are intrinsically different, in the sense that they produce non‐isomorphic models of Th$(\mathbb {R}_{\mbox{an, exp}})$; the elementary theory of the ordered field of real numbers, with the exponential function and restricted analytic functions. 相似文献
44.
Faiçal Abdmouleh Salma Charfi Aref Jeribi 《Journal of Mathematical Analysis and Applications》2012,386(1):83-90
In this paper, we consider the sum and the product of two operators acting on a Banach space and we present some new and quite general conditions to investigate their Wolf, Schechter and Browder essential spectra. 相似文献
45.
Salma Nasrin 《Geometriae Dedicata》2014,173(1):83-88
For three coadjoint orbits \(\mathcal {O}_1, \mathcal {O}_2\) and \(\mathcal {O}_3\) in \(\mathfrak {g}^*\) , the Corwin–Greenleaf function \(n(\mathcal {O}_1 \times \mathcal {O}_2, \mathcal {O}_3)\) is given by the number of \(G\) -orbits in \(\{(\lambda , \mu ) \in \mathcal {O}_1 \times \mathcal {O}_2 \, : \, \lambda + \mu \in \mathcal {O}_3 \}\) under the diagonal action. In the case where \(G\) is a simple Lie group of Hermitian type, we give an explicit formula of \(n(\mathcal {O}_1 \times \mathcal {O}_2, \mathcal {O}_3)\) for coadjoint orbits \(\mathcal {O}_1\) and \(\mathcal {O}_2\) that meet \(\left( [\mathfrak {k}, \mathfrak {k}] + \mathfrak {p}\right) ^{\perp }\) , and show that the formula is regarded as the ‘classical limit’ of a special case of Kobayashi’s multiplicity-free theorem (Progr. Math. 2007) in the branching law to symmetric pairs. 相似文献
46.
Salma Tabassum Suhail Sabir Othman Sulaiman Rokiah Hashim 《Journal of Dispersion Science and Technology》2013,34(5):710-716
The reaction of the common pain reliever acetaminophen (paracetamol, 4-acetamidophenol) with dichromate was investigated over time under conditions that simulate wastewater disinfection. The occurrence of the acetaminophen in the water bodies, especially in drinking water resources, has received considerable attentions. In situ chemical oxidation is a promising cost-effective treatment method to remove acetaminophen from water body as it degrades the drug to large extent. Experimental results indicate that the reaction is second order overall and first order with respect to both dichromate and acetaminophen, and has activation energy of 14.1 kJ/mol. The second-order rate constant ranges from 1.56 × 10?3 to 13.4 × 10?3 min?1 at temperature from 35 to 65°C. The acetaminophen degradation rates can be accelerated through increasing reaction temperature and oxidant concentration. The reaction under acid conditions was slightly faster than under alkaline or neutral conditions. Two of the products were unequivocally identified as the toxic compounds 1,4-benzoquinone and ammonium ions. These results demonstrate that acetaminophen is likely to be transformed significantly into toxic product if dichromate is used as an oxidizing agent during wastewater treatment. 相似文献
47.
Salma Abdeljalil Ines Ben Hmad Walid Saibi Bahia Amouri Wiem Maalej Marwa Kaaniche Aida Koubaa Ali Gargouri 《Applied biochemistry and biotechnology》2014,172(3):1599-1611
Stachybotrys microspora is a filamentous fungus characterized by the secretion of multiple hydrolytic activities (cellulolytic and non-cellulolytic enzymes). The production of these biocatalysts was studied under submerged culture using glucose, cellulose, and wheat bran as carbon sources. Endoglucanases, pectinases, xylanases, β-glucanases, chitinases, and proteases were induced on cellulose-based medium and repressed on glucose in both strains with higher amounts produced by the mutant. β-glucosidases were roughly equally produced by both strains under glucose and cellulose conditions. The yield of chitinases, β-glucanases, and proteases produced by Stachybotrys strains was as much higher than the commercialized lysing enzyme called “zymolyase,” currently used in yeast DNA extraction. In this context, we showed that S. microspora hydrolases can be successfully applied in the extraction of yeast DNA. 相似文献
48.
Pietro De Giovanni Salma Karray Guiomar Martín-Herrán 《European Journal of Operational Research》2019,272(2):465-480
Most of the cooperative advertising literature has focused on studying the effects of such programs considering marketing variables. This paper integrates production and inventory management with pricing and advertising considerations to assess the effects of cooperative advertising programs in bilateral monopolies. We consider a supply chain where a Vendor Managed Inventory (VMI) along with a consignment contract is implemented to coordinate the chain. We develop and solve a differential model for two games. The first one is a benchmark scenario where no cooperative advertising is offered, while the manufacturer offers the cooperative program in the second game. The main results show that cooperative advertising programs, usually considered as successful marketing initiatives, can be very difficult to implement in a supply chain undertaking a VMI policy with a consignment contract, in which operations and marketing interface is taken into account. A cooperative program mainly hurts the manufacturer’s profits, and can be profit-Pareto-improving only in a few cases. Although the retailer is generally willing to receive a support from the manufacturer, she can opt for a non-cooperative program when the largest part of the supply chain profits goes to the manufacturer. We developed several special cases to strengthen our findings. 相似文献
49.
Chandra AK Parveen S Das S Zeegers-Huyskens T 《Journal of computational chemistry》2008,29(9):1490-1496
The optimized geometry of isolated trimethylamine (TMA), its hydrogen bond complexes with phenol derivatives and protonated TMA is calculated at the B3LYP/6-31++G(d,p) level. A natural bond orbital (NBO) analysis on these systems is carried out at the same level of theory. In isolated TMA, one of the C-H bond in each of the three CH(3) groups is more elongated than the two other ones. As revealed by the NBO data, this results from a hyperconjugative interaction from the N lone pair to the sigma*(C-H) orbitals of the C-H bonds being in a transoid position with respect to the N lone pair. The formation of an intermolecular OH...N hydrogen bond with phenols results in a decrease of the lone pair effect. A linear correlation is found between the decrease in occupation of the sigma*(C-H) orbitals and the decrease in the hyperconjugative interaction energy in the complexes and isolated TMA. Complex formation with phenols results in a blue shift of 55-74 cm(-1) of the C-H stretching vibrations involved in the lone pair effect. Smaller blue shifts between 14 and 23 cm(-1) are predicted for the other C-H bonds. In these complexes, a linear correlation is found between the frequency shifts and the elongation of the C-H bonds. Protonation of TMA results in a nearly equalization of all the C-H distances and a blue shift of 180 cm(-1) of the C-H bonds involved in hyperconjugation with the N lone pair. 相似文献
50.
Salma Trady Abdellatif Hasnaoui M’hammed Mazroui Khalid Saadouni 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(10):223
In this study we examine the structural properties of single-component metallic glasses of aluminum. We use a molecular dynamics simulation based on semi-empirical many-body potential, derived from the embedded atom method (EAM). The radial distribution function (RDF), common neighbors analysis method (CNA), coordination number analysis (CN) and Voronoi tessellation are used to characterize the metal’s local structure during the heating and cooling (quenching). The simulation results reveal that the melting temperature depends on the heating rate. In addition, atomic visualization shows that the structure of aluminum after fast quenching is in a glassy state, confirmed quantitatively by the splitting of the second peak of the radial distribution function, and by the appearance of icosahedral clusters observed via CNA technique. On the other hand, the Wendt-Abraham parameters are calculated to determine the glass transition temperature (Tg), which depends strongly on the cooling rate; it increases while the cooling rate increases. On the basis of CN analysis and Voronoi tessellation, we demonstrate that the transition from the Al liquid to glassy state is mainly due to the formation of distorted and perfect icosahedral clusters. 相似文献