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741.
Zahida
Ehsan Muhammad M. Abbasi Samiran Ghosh Majid Khan Muddasir Ali 《等离子体物理论文集》2020,60(9):e202000030
A theoretical model is presented to study the characteristics of dust acoustic shock in a viscous, magnetized, rotating dusty plasma at both fast and slow time scales. By employing the reductive perturbation technique, the non-linear Zakharov–Kuznetsov–Burger (ZKB) equation is derived for both cases when the dust is inactive and dynamic (fast and slow time scales). Both electrons and ions are considered to follow the kappa/Cairns distribution. It is observed that in both cases, i.e. when dust is in the background and active, viscosity plays a key role in dissipation for the propagation of acoustic shock. Magnetic field and rotation are responsible for the dispersive term. Superthermality is found to affect significantly the formation of the shock wave along with viscous nature of plasma, whereas the dust charge affects the non-linear coefficient of the ZKB equation. The present investigation may be beneficial to the understanding of the rotating plasma, in particular the experiments being carried out. 相似文献
742.
Syed Shaheen Shah Sulayman Oladepo Muhammad Ali Ehsan Wissam Iali Asem Alenaizan Mohammad Nahid Siddiqui Munetaka Oyama Abdul-Rahman Al-Betar Md. Abdul Aziz 《Chemical record (New York, N.Y.)》2024,24(1):e202300105
Polyaniline (PANI) has piqued the interest of nanotechnology researchers due to its potential as an electrode material for supercapacitors. Despite its ease of synthesis and ability to be doped with a wide range of materials, PANI′s poor mechanical properties have limited its use in practical applications. To address this issue, researchers investigated using PANI composites with materials with highly specific surface areas, active sites, porous architectures, and high conductivity. The resulting composite materials have improved energy storage performance, making them promising electrode materials for supercapacitors. Here, we provide an overview of recent developments in PANI-based supercapacitors, focusing on using electrochemically active carbon and redox-active materials as composites. We discuss challenges and opportunities of synthesizing PANI-based composites for supercapacitor applications. Furthermore, we provide theoretical insights into the electrical properties of PANI composites and their potential as active electrode materials. The need for this review stems from the growing interest in PANI-based composites to improve supercapacitor performance. By examining recent progress in this field, we provide a comprehensive overview of the current state-of-the-art and potential of PANI-based composites for supercapacitor applications. This review adds value by highlighting challenges and opportunities associated with synthesizing and utilizing PANI-based composites, thereby guiding future research directions. 相似文献
743.
Phase diagrams and liquid–liquid equilibrium (LLE) data of the aqueous poly(propylene glycol) (PPG) + di-sodium hydrogen phosphate and PPG + tri-sodium phosphate two-phase systems have been determined experimentally at 298.15, 303.15, 308.15, 313.15 and 318.15 K. The effects of temperature and charge on the anion of electrolyte on the binodal curves and tie-lines have been studied and it was found that an increasing in temperature and charge on the anion caused the expansion of two-phase region. The results show that the effect of charge on the anion of electrolyte on the binodal curves becomes smaller by increasing temperatures. It was also found that the concentration of salt, which is in equilibrium with a certain concentration of PPG, decreases by increasing temperature. Based on cloud point values, the energetics of the clouding process has been estimated and it was found that entropy increase is the driving force for biphasic formation. 相似文献
744.
The selective laser excitation and induced fluorescence observation technique has been used to study rotationally inelastic collisions of I2*(B 0u+, υ = 15,j) with I2, 3He, 4He, Ne, Ar, H2 and D2. For each collision partner, several initial rotational levels ranging from ji = 12 up to ji = 146 have been excited. For purely rotational transfer within the υ = 15 level, our data are perfectly consistent with energy sudden (eventually corrected) scaling laws. Thus, any thermally averaged rate constant, k(ji → jf), can be expressed as a function of the basis rate constants k(l → 0). Furthermore, these k(l → 0) are found to follow simple empirical fitting laws. Consequently any k(ji → jf) can be predicted given a set of two or three fitting parameters. Collisions with relatively heavy particles (I2, Ar and Ne) are well described by using the inverse power fitting law k(l → 0) = b[l(l+1)]?γ, where b = 1.7, 1.2 and 1.2×10?10 cm3 s?1 and γ = 1.08, 1.02 and 1.17 for I2*-Ne, I2*-Ar and I2*-I2 collisions respectively. For collisions with light particles (3He, 4He, H2 and D2), k(l → 0) shows a sharp decrease with l which can be accounted for by a hybrid power-exponential fitting law k(l → 0) = b[l(l+1)]?γ exp[-l(l+1)/l* (l*+1)], where b = 0.84, 0.71, 2.77 and 2.78×10?10 cm3 s?1l+ = 20.6, 23.1, 18.8 and 31.4, and γ = 0.66, 0.66, 0.78 and 0.91 for I2*-3He, I2*-He, I2*-H2 and I2*-D2 collisions, respectively. We confirm that the rotational transfer dynamics in heavy molecules is mainly governed by angular momentum exchange. 相似文献
745.
746.
Hamid R. Memarian Majid M. Sadeghi Ahmad R. Momeni Dietrich Döpp 《Monatshefte für Chemie / Chemical Monthly》2002,133(5):661-667
Summary. Some novel 3,5-diacetyl-1,4-dihydropyridine derivatives were synthesized; their photochemical behaviour was studied under
oxygen or argon atmosphere. Irradiation of these compounds resulted in the aromatization of the ring and formation of 3,5-diacetylpyridine
derivatives. The presence of oxygen plays an important role in the type, rate, or failure of oxidation. Irradiation of these
compounds with of 2-furyl or 5-methyl-2-furyl substituents in position 4 under argon resulted in the formation of a pyridine
ring with retention of these substituents, whereas loss of these substituents and ring aromatization was observed upon irradiation
under oxygen.
Received September 4, 2001. Accepted September 17, 2001 相似文献
747.
A A Saboury M S Atri M H Sanati M Sadeghi 《Journal of Thermal Analysis and Calorimetry》2006,83(1):175-179
A simple graphical linear
method was introduced for isothermal titration calorimetric data analysis
in the protein-ligand interaction. The number of binding sites, the dissociation
binding constant and the molar enthalpy of binding site can be obtained by
using this new isothermal titration calorimetric data analysis method. The
method was applied to the study of the interaction of human growth hormone
(hGH) with divalent calcium ion at 27°C in NaCl solution, 50 mM. hGH has
a set of three identical and independent binding sites for Ca 2+
. The intrinsic dissociation equilibrium constant and the molar enthalpy of
binding are 52 μMand -17.4, respectively. Results obtained by this
new calorimetric data analysis are in good agreement with results obtained
using our previous method. 相似文献
748.
M. Sadeghi P. Van den Winkel H. Afarideh M. Haji-Saeid 《Journal of Radioanalytical and Nuclear Chemistry》2005,262(3):665-672
The Rh target preparation for production of 103Pd was investigated by using a thick electrodeposition of rhodium metal on a copper backing. The electrodeposition experiments were performed in acidic sulfate media using RhCl3·3H2O, Rh2(SO4)3 (recovered from hydrochloric acid solution) and also in the commercially available Rhodex plating baths. For high current beam irradiation of a Rh target, the qualities of the deposit of the three baths were compared in terms of thermal shock, crack-free and morphology criteria. The quality of the plating obtained from a sulfate bath [Rh2(SO4)3] was comparable with the one obtained from commercially available Rhodex bath. The optimum conditions of the electrodepositions were as follows: 4.8 g rhodium [as Rh2(SO4)3], pH 2, DC current density of ca 8.5 mA·cm–2, 1% sulfamic acid (w/v) and temperature 40–60 °C.The authors would like to thank their colleagues at the VUB-Cyclotron department for help and assistance in preparation of the electrodeposition equipment and taking the SEM photomicrographs and also K. Aardaneh (NRCAM) for his assistance. 相似文献
749.
750.
H. Loghmani-Khouzani M. M. Sadeghi R. Ranjbar-Karimi 《Journal of the Iranian Chemical Society》2005,2(4):330-333
2- Or 4-Difluoronitromethyl and 2- or 4-fluoronitrobenzyl substituted pyridines, quinolines, phenantheridine, benzothiazol and benzoxazol were synthesized by reaction of the corresponding nitro compounds in the presence of 1-chloromethyl-4-fluoro-1,4-diazoiabicyclo[2,2,2]octane bis(tetrafluoroborate) (Select-Fluor) and ammonium acetate as a base under microwave irradiation. This method is very efficient and the yields were significantly improved in comparison to the previous reports. 相似文献