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排序方式: 共有1115条查询结果,搜索用时 10 毫秒
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Dr. Anna Notaro Marta Jakubaszek Severin Koch Dr. Riccardo Rubbiani Dr. Orsolya Dömötör Dr. Éva A. Enyedy Mazzarine Dotou Dr. Fethi Bedioui Mickaël Tharaud Dr. Bruno Goud PD Dr. Stefano Ferrari Prof. Dr. Enzo Alessio Dr. Gilles Gasser 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(22):4997-5009
Cancer is one of the main causes of death worldwide. Chemotherapy, despite its severe side effects, is to date one of the leading strategies against cancer. Metal-based drugs present several potential advantages when compared to organic compounds and they have gained trust from the scientific community after the approval on the market of the drug cisplatin. Recently, we reported the ruthenium complex ([Ru(DIP)2(sq)](PF6) (where DIP is 4,7-diphenyl-1,10-phenantroline and sq is semiquinonate) with a remarkable potential as chemotherapeutic agent against cancer, both in vitro and in vivo. In this work, we analyse a structurally similar compound, namely [Ru(DIP)2(mal)](PF6), carrying the flavour-enhancing agent approved by the FDA, maltol (mal). To possess an FDA approved ligand is crucial for a complex, whose mechanism of action might include ligand exchange. Herein, we describe the synthesis and characterisation of [Ru(DIP)2(mal)](PF6), its stability in solutions and under conditions that resemble the physiological ones, and its in-depth biological investigation. Cytotoxicity tests on different cell lines in 2D model and on HeLa MultiCellular Tumour Spheroids (MCTS) demonstrated that our compound has higher activity than cisplatin, inspiring further tests. [Ru(DIP)2(mal)](PF6) was efficiently internalised by HeLa cells through a passive transport mechanism and severely affected the mitochondrial metabolism. 相似文献
24.
A Quantitative Model for Alkane Nucleophilicity Based on C−H Bond Structural/Topological Descriptors
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Stuart Carter Nicholas C. Handy Cristina Puzzarini Riccardo Tarroni Paolo Palmieri 《Molecular physics》2013,111(21):1697-1712
A general method is presented for the evaluation of the spin rovibronic energy levels of triatomic molecules with up to three interacting potential energy surfaces. The full theory is outlined in detail, both for singlet and for doublet electronic states and the method is then applied to the benchmark example of C2H. High quality multireference configuration interaction calculations have been carried out to generate the 3-dimensional near-equilibrium adiabatic potential energy surfaces of the three lowest 12A'(X2Σ+), 22A'(A2Π), 12A''(A2Π) electronic states of C2H, and the pair of interacting states of A 0 symmetry have then been diabatized. Results are presented for J up to 7/2 and compared with gas-phase high resolution experimental results for energies up to 5600 cm1. 相似文献
27.
Riccardo Boero Marco Castellani Flaminio Squazzoni 《Computational & Mathematical Organization Theory》2008,14(2):156-174
The paper aims at presenting an agent-based modeling exercise to illustrate how small differences in the cognitive properties
of agents can generate very different macro social properties. We argue that it is not necessary to assume highly complicated
cognitive architectures to introduce cognitive properties that matter for computational social science purposes. Our model
is based on different simulation settings characterized by a gradual sophistication of behavior of agents, from simple heuristics
to macro-micro feedback and other second-order properties. Agents are localized in a spatial interaction context. They have
an individual task but are influenced by a collective coordination problem. The simulation results show that agents can generate
efficiency at a macro level particularly when socio-cognitive sophistication of their behavior increases.
相似文献
Flaminio Squazzoni (Corresponding author)Email: |
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Riccardo Molle Donato Passaseo 《Calculus of Variations and Partial Differential Equations》2014,49(1-2):861-907
We present some multiplicity results concerning semilinear elliptic Dirichlet problems with jumping nonlinearities where the jumping condition involves a set of high eigenvalues not including the first one. Using a variational method we show that the number of solutions may be arbitrarily large provided the number of jumped eigenvalues is large enough. Indeed, we prove that for every positive integer $k$ there exists a positive integer $n(k)$ such that, if the number of jumped eigenvalues is greater than $n(k),$ then the problem has at least a solution which presents $k$ peaks. Moreover, we describe the asymptotic behaviour of the solutions as the number of jumped eigenvalues tends to infinity; in particular, we analyse some concentration phenomena of the peaks (near points or suitable manifolds), we describe the asymptotic profile of the rescaled peaks, etc $\ldots $ 相似文献
29.
Amorati R Catarzi F Menichetti S Pedulli GF Viglianisi C 《Journal of the American Chemical Society》2008,130(1):237-244
Rotation about the Ar-S bond in ortho-(alkylthio)phenols strongly affects the bond dissociation enthalpy (BDE) and the reactivity of the OH group. Newly synthesized sulfur containing heterocycles 3 and 4, where the -SR group is almost coplanar with the phenolic ring, are characterized by unusually low BDE(O-H) values (79.6 and 79.2 kcal/mol, respectively) and by much higher reactivities toward peroxyl radicals than the ortho-methylthio derivative 1 (82.0 kcal/mol). The importance of the intramolecular hydrogen bond (IHB) in determining the BDE(O-H) was demonstrated by FT-IR experiments, which showed that in heterocycles 3 and 4 the IHB between the phenolic OH group and the S atom is much weaker than that present in 1. Since the IHB can be formed only if the -SR group adopts an out-of-plane geometry, this interaction is possible only in the methylthio derivative 1 and not in 3 and 4. The additive contribution to the phenolic BDE(O-H) of the -SR substituent therefore varies from -3.1 to +2.8 kcal/mol for the in-plane and out-of-plane conformations, respectively. These results may be relevant to understanding the role of the tyrosine-cysteine link in the active site of galactose oxidase, an important enzyme that catalyzes the two-electron aerobic oxidation of primary alcohols to aldehydes. The switching of the ortho -SR substituent between perpendicular and planar conformations may account for the catalytic efficiency of this enzyme. 相似文献
30.
A new route for the synthesis of stable 3-alkyl- and 3-aryl-2(,2)-(di)fluoroaziridines was developed by hydride reduction of novel alpha-bromo- and alpha-chloro-alpha(,alpha)-(di)fluoroketimines and subsequent ring closure of beta-fluorinated beta-chloro- and beta-bromoamines. This is the first report on the synthesis of 2,2-difluoroaziridines sensu stricto. 相似文献