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91.
V. I. Pet’kov E. A. Asabina A. V. Markin N. N. Smirnova 《Journal of Thermal Analysis and Calorimetry》2008,91(1):155-161
Data on synthesis, thermal behavior and thermodynamic properties for the NZP phosphates NaMe2(PO4)3 and Na5Me(PO4)3 (Me=Ti, Zr, Hf) are reported. The compounds were synthesized by sol-gel method and solid-state reactions and characterized by
X-ray powder diffraction, IR spectroscopy, electron microprobe and chemical analysis. Their thermal behavior was studied by
the DTA measurements. The heat capacities of the phosphates were measured between temperatures 7 and 650 K. The fractal dimensions
for the phosphates were calculated. The obtained thermodynamic characteristics of these phosphates and also literature data
for the compounds of NZP type structure are summarized. 相似文献
92.
93.
The electronic energy loss of hydrogen ions (protons and deuterons) in thin supported films of LiF has been studied in backscattering geometry for specific energies from 700 eV/u to 700 keV/u, using Rutherford backscattering spectroscopy and time-of-flight low-energy ion scattering spectroscopy. For specific energies below 8 keV/u, our data confirm velocity proportionality for the stopping cross section epsilon (like in a metal) down to 3.8 keV/u, as observed previously for protons and antiprotons despite the large band gap (14 eV) of LiF. Below 3.8 keV/u, the present results indicate an apparent velocity threshold at about 0.1 a.u. for the onset of electronic stopping. 相似文献
94.
V. I. Pet’kov A. S. Shipilov A. V. Markin N. N. Smirnova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2018,92(4):646-652
The temperature dependence of heat capacity C° p = f(T) of crystalline arsenate Mg0.5Zr2(AsO4)3 was studied by precision adiabatic vacuum and differential scanning calorimetry in the temperature range 8?670 K. The standard thermodynamic functions C° p (T), H°(T)–H°(0), S°(T), and G°(T)–H°(0) of the arsenate for the range from Т → 0 to 670 K and the standard formation entropy at Т = 298.15 K were calculated from the obtained experimental data. Based on the low-temperature capacity data (30–50 K) the fractal dimension D of the arsenate was determined, and the topology of its structure was characterized. The results were compared with the thermodynamic data for the structurally related crystalline phosphates M0.5Zr2(PO4)3 (M = Mg, Ca, Sr, Ba, Ni) and arsenate NaZr2(AsO4)3. 相似文献
95.
N.N. Smirnova O.V. Stepanova T.A. Bykova A.V. Markin A.M. Muzafarov E.A. Tatarinova V.D. Myakushev 《Thermochimica Acta》2006,440(2):188-194
In the present work temperature dependences of heat capacity of carbosilane dendrimers with butyl terminal groups of the third and the fourth generations as well as of the fifth and the sixth generations have been determined first in the range from 6 to 340 K and between 6 and 600 K, respectively, by precision adiabatic vacuum and dynamic calorimetry. In the above temperature ranges the physical transformations have been detected and their thermodynamic characteristics have been estimated and analyzed. The experimental data were used to calculate standard thermodynamic functions, namely the heat capacity , enthalpy Ho(T) − Ho(0), entropy So(T) − So(0) and Gibbs function Go(T) − Ho(T), for the range from T → 0 to (340–600) K. Linear dependences of changing the corresponding thermodynamic functions of the dendrimers on their molecular weight and the number of butyl groups on an outer sphere have been determined. 相似文献
96.
N. N. Smirnova A. V. Markin L. Ya. Tsvetkova N. V. Kuchkina E. Yu. Yuzik-Klimova Z. B. Shifrina 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(5):887-892
The heat capacity of a glassy third-generation poly(phenylene-pyridyl) dendron decorated with dodecyl groups is studied for the first time via high-precision adiabatic vacuum and differential scanning calorimetry in the temperature range of 6 to 520 K. The standard thermodynamic functions (molar heat capacity Cp°, enthalpy H°(T), entropy S°(T), and Gibbs energy G°(T)-H°(0)) in the range of T → 0 to 480 K, and the entropy of formation at 298.15 K, are calculated on the basis of the obtained data. The thermodynamic properties of the dendron and the corresponding third-generation poly(phenylene-pyridyl) dendrimer studied earlier are compared. 相似文献
97.
A. G. Dedov A. S. Loktev A. A. Karavaev M. N. Kartasheva S. V. Markin I. I. Moiseev 《Doklady Chemistry》2016,471(1):334-337
The results of isobutanol conversion on micro-mesoporous composite MFI/MCM-41 synthesized using microwave irradiation were reported. It was shown that, unlike other described isobutanol conversion catalysts, this catalyst makes it possible to produce a hydrocarbon product containing a significant amount of aromatic hydrocarbons at low benzene content and also to avoid the undesirable formation of oxygen-containing products. 相似文献
98.
Markin G. V. Ketkov S. Yu. Lopatin M. A. Shavyrin A. S. Kuropatov V. A. Domrachev G. A. 《Russian Journal of Organic Chemistry》2017,53(3):445-448
Russian Journal of Organic Chemistry - New 1′,1′-dimethyl-2′,5′-dihydro-1′H-pyrrolo[3′,4′:1,9](C60-I h)[5,6]fulleren-1-ium iodides containing different... 相似文献
99.
100.
A bilinear time series (BLTS) model is expressed in the form of Akaike's Markovian representation in order to use the Kalman recursive estimation approach. It is shown that Akaike's Markovian representation of autoregressive moving average models of orderp and q (ARMA(p,q)) and that of the bilinear model are equivalent. This equivalence facilitates the maximum likelihood estimation of the parameters involved in the bilinear model, which otherwise is an unwieldy problem. The present approach can easily be extended to take into account missing observations 相似文献