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431.
G. de Angelis C. Fahlander A. Gadea E. Farnea W. Gelletly A. Aprahamian D. Bazzacco F. Becker P. G. Bizzeti A. Bizzeti-Sona F. Brandolini D. De Acuña M. De Poli J. Eberth D. Foltescu S. M. Lenzi S. Lunardi T. Martinez D. R. Napoli P. Pavan C. M. Petrache C. Rossi Alvarez D. Rudolph B. Rubio S. Skoda P. Spolaore G. Thomas C. Ur M. Weiszflog R. Wyss 《Acta Physica Hungarica A》1997,6(1-4):269-273
The structure of theN=Z nuclei60Zn,62Ga,64Ge, and72Kr has been investigated at GASP. Total Routhian surface (TRS) calculations have been performed for theN=36, 38 and 40 Kr isotones. In the case of72Kr the four quasi-particleg 9/2 alignment is observed to be significantly delayed in rotational frequency with respect to the heavier Kr isotopes. Such a delay contradicts the predictions of mean field calculations and may be viewed as the first sign of additional correlations in theT=0 pairing channel. 相似文献
432.
The Hellmann-Feynman theorem is applied to calculate the effects produced by substitutional impurities in a linear chain of atoms. In particular, within the tight binding Hamiltonian, we present exact results for the change in energy of the system caused by the impurity. 相似文献
433.
C. B. Collins F. Davanloo M. C. Iosif R. Dussart J. M. Hicks S. A. Karamian C. A. Ur I. I. Popescu V. I. Kirischuk J. M. Pouvesle P. McDaniel C. E. Crist 《Physics of Atomic Nuclei》2000,63(12):2067-2072
A sample containing 6.3×1014 nuclei of the 16+ isomer of 178Hf having a half-life of 31 yr and an excitation energy of 2.446 MeV was irradiated with x-ray pulses from a device operated at 15 mA to produce bremsstrahlung with an endpoint energy of 90 keV. The gamma spectra of the isomeric target were taken with a Ge detector. The intensity of the 325.5-keV (6+ → 4+) transition in the ground-state band of 178Hf was found to increase by about 2%. Such an enhanced decay of the 178Hf isomer is consistent with an integrated cross section value of 3×10?23 cm2 keV if resonance absorption occurs within energy ranges corresponding to the maxima of the x-ray flux, either near 20 keV or at the energies of the characteristic emission lines of W. 相似文献
434.
Urh Černigoj Jana Vidič Ana Ferjančič Urša Sinur Klemen Božič Nina Mencin Anže Martinčič Celjar Pete Gagnon Aleš Štrancar 《Electrophoresis》2021,42(24):2619-2625
Elution of strong and weak anion exchangers with sodium chloride gradients is commonly employed for analysis of sample mixtures containing different isomers of plasmid DNA. Gradient elution of a weak anion exchanger (diethylaminoethyl) in the presence of guanidine hydrochloride (Gdn) roughly doubles resolution between open-circular (oc) and supercoiled (sc) isomers. It also improves resolution among sc, linear, and multimeric/aggregated forms. Sharper elution peaks with less tailing increase sensitivity about 30%. However, elution with an exclusively Gdn gradient to 900 mM causes more than 10% loss of plasmid. Elution with a sodium chloride gradient while maintaining Gdn at a level concentration of 300 mM achieves close to 100% recovery of sc plasmid while maintaining the separation improvements achieved by exclusively Gdn elution. Corresponding improvements in separation performance are not observed on a strong (quaternary amine) anion exchanger. Other chaotropic salts do not produce a favorable result on either exchanger, nor does the inclusion of surfactants or EDTA. Selectivity of the diethylaminoethyl-Gdn method is orthogonal to electrophoresis, but with better quantification than agarose electrophoresis, better quantitative accuracy than CE, and resolution approaching CE. 相似文献
435.
Fakhar-e-Alam M. Firdous S. Atif M. Khan Y. Zaidi S. S. Z. Suleman R. Rehman A. Khan R. U. Nawaz M. Ikram M. 《Laser Physics》2011,21(12):2156-2164
Drug delivery into the malignant cell is a basic requirement for effectiveness of photosensitizing systems for photodynamic
therapy (PDT). For anticancer tumoricidal drugs, e.g., 5-aminolevulinic acid (ALA), zinc oxide (ZnO) nanoparticles (NPs) are
used as efficient intracellular photosensitizer carriers. Apoptotic effect of tumoricidal drugs (ALA and Photofrin cells in
the presence and absence of ZnO NPs using confocal microscopy as well as Neutral Red Assay (NRA). In dark, ZnO NPs conjugated
with ALA or Photofrinhas been found to have a remarkable fluorescence in Hepatucellular carcinoma (HepG2) cells. This fact
illustrates the great potential of ZnO NPs as biomarker in relevant clinical and biomedical applications. 相似文献
436.
Present study evaluates the effects of photodynamic therapy (PDT) with aminolevulinic acid (5-ALA) as photo sensitizer using Human embryonic kidney (HEK293T) cell line as an experimental model. Porphyrins derivatives are used as active cytotoxic antitumor agents in PDT. Above mentioned cell line were irradiated with red light (a diode laser, λ = 635 nm) at different doses (0–160 J/cm2) of light. The influence/effectiveness of incubation time, various concentrations of aminolevulinic acid (5-ALA) and light doses on the cellular viability was studied. HEK293T cells were deliberated by exposing the ALA-PpIX (0–1000 μg/ml) of concentrations. The optimal uptakes of photosensitizer (PS) in cell lines were investigated by means of spectro photo metric measurements. Cells viability was determined by means of neutral red assay (NRA). It was observed that alone, neither photosensitizer nor light dose have significant effect on cells viability, but optimal concentration of PS along with suitable dose of light exhibit effective impact on the viability of cell. Our results showed that light doses of 40 J/cm2 demonstrates effective PDT outcome for HEK293T cell line when incubated with 400 μg/ml, with wrapping up view that HEK293T cell line is very sensitive to ALA-mediated PDT as compared to cell line published in our data. At the end results has been verified by using reactive oxygen species (ROS) measure test. 相似文献
437.
Javid Hussain Najeeb Ur Rehman Hidayat Hussain Liaqat Ali Ahmed Al‐Harrasi Viqar Uddin Ahmad 《Helvetica chimica acta》2011,94(11):2106-2110
The structure elucidation of two new phthalate derivatives named nepethalates A ( 1 ) and B ( 2 ) is reported. Both of these secondary metabolites were isolated from the MeOH extract of Nepeta clarkei. HR‐EI‐MS, IR and UV absorption spectrometry, and NMR experiments including COSY, HMQC, and HMBC were used for the determination of the structures and complete 1H‐ and 13C‐NMR assignments. 相似文献
438.
439.
Marija Drev Urša Opara Krašovec Mateja Hočevar Marko Berginc Marjeta Kržmanc Maček Marko Topič 《Journal of Sol-Gel Science and Technology》2011,59(2):245-251
The influence that the degree of polyesterification has on a titanium sol (Ti-sol) prepared via the Pechini method that acts
as a matrix in TiO2 pastes used for dye sensitized solar cells is reported. The different content of the polyester in the Ti-sol was realized
by varying the heating time of the Ti-sol. Titanium dioxide pastes were prepared by introducing a commercial TiO2 nanopowder into the Ti-sols. The TiO2 layers were tested as photoanodes in dye-sensitized solar cells (DSSCs). The most appropriate degree of polyesterification
was achieved by heating the Ti-sol for 0.5 and 1 h, while longer heating deteriorates the TiO2 layer morphology. The highest efficiency of the DSSCs based on an ionic liquid electrolyte was 6.3% measured under standard
test conditions (100 mW/cm2, AM 1.5, 25 °C). 相似文献
440.
Muhammad Rafique Abdul Jabbar Abdul Razzaq Khan Saeed Ur Rahman Muhammad Basharat Azhar Mehmood Matiullah 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(3):2049-2056
In this article, we present results obtained from a radiometric survey that was conducted in the Leepa Valley of Azad Jammu & Kashmir, Pakistan. The purpose of current study is to appraise the radioactivity levels and the associated health hazards due to the terrestrial radionuclide in soil and rock samples. In this regard, 16 soil and 17 rock samples were collected from different locations of the Leepa Valley. After processing the samples, activity concentrations of primordial (232Th, 226Ra and 40K) and anthropogenic (137Cs) radionuclides were determined using a P-type coaxial high purity germanium detector. From the results obtained the mean activity concentrations of radionuclides 226Ra, 232Th and 40K in the soil samples were found to be 31.25 ± 0.46, 44.1 ± 1.07 and 575 ± 8.89 Bq kg?1 respectively. Whilst, in rock samples 226Ra, 232Th and 40K mean activities were found as 28.46 ± 0.45, 48.63 ± 1.12 and 666.7 ± 9.39 Bq kg?1, respectively. The 137Cs concentration level in soil and rock samples is found to be 15.04 ± 0.29 and 5.7 ± 0.16 Bq kg?1, respectively. The average radium equivalent activity (R aeq) was found as 143.16 and 142.93 Bq kg?1 in soil and rock samples, respectively. These findings are less than the recommended safe value of 370 Bq kg?1 as given in OECD report (1979). The values of external (H ex) and internal hazard index (H in) are also less than unity. Mean value of absorbed dose rate was found as 69.78 nGy h?1 for the soil samples, which is in good agreement with the world wide average value (70 nGy h?1). Mean value of absorbed dose rate from rock samples was found as 70.01 nGy h?1. Mean values of the annual effective dose is also lower than the values reported for different other countries of the world. 相似文献