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111.
Anand P. Santhanam Yugang Min Sudhir P. Mudur Abhinav Rastogi Bari H. Ruddy Amish Shah Eduardo Divo Alain Kassab Jannick P. Rolland Patrick Kupelian 《Comptes Rendus Mecanique》2010,338(7-8):461-473
A method to estimate the deformation operator for the 3D volumetric lung dynamics of human subjects is described in this paper. For known values of air flow and volumetric displacement, the deformation operator and subsequently the elastic properties of the lung are estimated in terms of a Green's function. A Hyper-Spherical Harmonic (HSH) transformation is employed to compute the deformation operator. The hyper-spherical coordinate transformation method discussed in this paper facilitates accounting for the heterogeneity of the deformation operator using a finite number of frequency coefficients. Spirometry measurements are used to provide values for the airflow inside the lung. Using a 3D optical flow-based method, the 3D volumetric displacement of the left and right lungs, which represents the local anatomy and deformation of a human subject, was estimated from 4D-CT dataset. Results from an implementation of the method show the estimation of the deformation operator for the left and right lungs of a human subject with non-small cell lung cancer. Validation of the proposed method shows that we can estimate the Young's modulus of each voxel within a 2% error level. 相似文献
112.
A Facile One‐Pot Synthesis and Anticancer Evaluation of Novel Substituted 1,2‐Dihydropyridine and 1,2,3,4‐Tetrahydropyrimidine Analogues 下载免费PDF全文
Ahmed Bari Mohammad Khalid Parvez Azmat Ali Khan Amer M. Alanazi Saeed Ali Syed Mohammed S. Al‐Dosari Abdulrahman M. Alobaid 《Journal of heterocyclic chemistry》2016,53(2):377-382
Current paper involves the one‐pot synthesis of various 1,2‐dihydropyridine and 1,2,3,4‐tetrahydropyrimidine analogues. The antitumor activity of the synthesized compounds has been carried out against various human cancer cell lines, and some of the analogues are found to be potent. 相似文献
113.
Dr. Lucas Frédéric Bibiana Fabri Dr. Laure Guénée Dr. Francesco Zinna Prof. Lorenzo Di Bari Prof. Jérôme Lacour 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(56):e202201853
In essentially one-pot, using Ir- and Pd-catalysis, tris(arene)-functionalized cationic [4]helicenes are synthesized with full regioselectivity and enantiospecificity starting from a trivial precursor (17 examples). This poly-addition of aryl groups improves key optical properties, that is, fluorescence quantum yields and lifetimes. Electronic circular dichroism and circularly polarized luminescence signatures are observed up to the far-red domain, in particular with additional arenes prone to aggregation. 相似文献
114.
Cristina Maria Di Bari 《Rendiconti del Circolo Matematico di Palermo》1979,28(2):229-238
We prove that some caracterizations of differentiable real valued functions ([1], [2], [4]) are valid also if these functions take values in a reflexive real Banach space. 相似文献
115.
B. Ghyselen M. A. Bari E. J. Tarte M. G. Blamire R. E. Somekh Y. Yan J. E. Evetts 《Physica C: Superconductivity and its Applications》1994,230(3-4):327-339
We have fabricated sandwich SNS (superconductor/normal metal/superconductor) junctions using in-situ grown c-axis oriented YBaCuO/PrBaCuO/YBaCuO trilayers. We observe supercurrents for PrBaCuO thicknesses up to 130 nm at 4.2 K. To confirm or rule out the presence of shorts through the barrier, the junction behaviour has been further characterised. Magnetic-field and PrBaCuO thickness dependences of the critical current, as well as a correct scaling with the junction area of both the critical current and the normal resistance, appear to indicate a reasonable uniformity for the barriers on the scale of the size of the junctions, typically 10 μm. These results suggest that either we are observing real c-axis transport in PrBaCuO or, if the behaviour is defect dominated, that the criteria commonly used to demonstrate good device behaviour should be applied carefully. The temperature dependence of the junction critical current and normal resistance are also reported and compared. 相似文献
116.
Mojca Čakić Semenčić Maja Dropučić Lidija Barišić Krešimir Molčanov Vladimir Rapić 《Structural chemistry》2007,18(3):273-278
N-Acetyl-(1-ferrocenylethyl)amine (8) was synthesized by N-acylation of (1-ferrocenylethyl)amine (7) in 84% yield. Reaction of N-acetyl-[1-(1′-bromo-ferrocenyl)ethyl]amine (4) (which was prepared by multistep sequence starting from bromoferrocene) with n-BuLi/ClCOOEt gave 77% of N-acetyl-N-ethoxycarbonyl-(1-ferrocenylethyl)amine (6) instead of the expected ethyl 1′-[1-(acetamido)ethyl]ferrocene-1-carboxylate (5). Both structures were undoubtedly confirmed by (HR)MS spectroscopy and single crystal X-ray structure analysis. 相似文献
117.
It is shown that destabilization energy of organic molecules containing small rings can be estimated by quasi–homodesmotic
reactions involving acyclic “strain–free” counterparts. These destabilization energies Es can be well reproduced at the HF level employing cc-pVTZ basis set, because the contributions of the electron correlation
and ZPV energy practically cancel each other in most cases. A predominating factor leading to a decreased stability of molecules
involving small ring fragments is given by the Ω bond bending or Baeyer strain. It leads to a dramatic decrease in the electron–nuclei
attraction, which is a hallmark of the angular strain. Similar results are obtained by the DFT–B3LYP method. It is strongly
pointed out that Baeyer strain cannot be singled out from the total destabilization energy in a precise quantitative way,
since it is interlocked with other types of intramolecular interactions like the nonbonded repulsions, a significant increase
in the stability of the CH bonds emanating from the small cyclic structures and by the σ–aromaticity or σ–antiaromaticity in three– and four–membered rings, respectively. Nevertheless, it is fair to say that Baeyer strain is the
essential factor in determining decreased stability of small ring compounds and that the diminished electron–nuclear attraction
is its characteristic signature at the global level.
Dedicated to Professor Karl Jug on the occasion of his 65th birthday. 相似文献
118.
A.L. Bhuiyan 《European Polymer Journal》1983,19(3):195-198
The mechanism of thermal degradation of wholly aromatic polyamides has been investigated in the light of several thermodynamic parameters, such as resonance stabilization of the free radicals formed, bond enthalpy changes and entropy changes. It has been shown that the scission of the NH bond in the beginning is both thermodynamically and kinetically favoured over the scission of the aromatic ring-carbonyl carbon bond. CN bond and the aromatic ringNH bond in the polymer chain backbone. Formation of the major products and some minor products has been explained with the help of the proposed mechanism. 相似文献
119.
Gerelli Y Barbieri S Di Bari MT Deriu A Cantù L Brocca P Sonvico F Colombo P May R Motta S 《Langmuir : the ACS journal of surfaces and colloids》2008,24(20):11378-11384
The combined use of cryo-TEM, dynamic light scattering, and small-angle X-ray and neutron scattering techniques allows a detailed structural model of complex pharmaceutical preparations of soybean lecithin/chitosan nanoparticles used as drug vectors to be worked out. Charge-driven self-organization of the lipid(-)/polysaccharide(+) vesicles occurs during rapid injection, under mechanical stirring, of an ethanol solution of soybean lecithin into a chitosan aqueous solution. We conclude that beyond the charge inversion region of the phase diagram, i.e., entering the redissolution region, the initial stages of particle formation are likely to be affected by a re-entrant condensation effect at the nanoscale. This behavior resembles that at the mesoscale which is well-known for polyion/amphiphile systems. Close to the boundary of the charge inversion region, nanoparticle formation occurs under a maximum condensation condition at the nanoscale and the complexation-aggregation process is driven toward a maximum multilamellarity. Interestingly, the formulation that maximizes vesicle multilamellarity corresponds to that displaying the highest drug loading efficiency. 相似文献
120.
Bari S Sobocinski P Postma J Alvarado F Hoekstra R Bernigaud V Manil B Rangama J Huber B Schlathölter T 《The Journal of chemical physics》2008,128(7):074306
The interaction of keV He(+), He(2+), and O(5+) ions with isolated alpha and beta isomers of the amino acid alanine was studied by means of high resolution coincidence time-of-flight mass spectrometry. We observed a strong isomer dependence of characteristic fragmentation channels which manifests in strongly altered branching ratios. Despite the ultrashort initial perturbation by the incoming ion, evidence for molecular rearrangement leading to the formation of H(3)(+) was found. The measured kinetic energies of ionic alanine fragments can be sufficient to induce secondary damage to DNA in a biological environment. 相似文献