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181.
The conducting polymer electrolyte films consisting of polyacrylonitrile (PAN) as the host polymer, lithium triflate (LiCF3SO3) and sodium triflate (NaCF3SO3) as inorganic salts were prepared by the solution-cast technique. The pure PAN film was prepared as a reference. The ionic
conductivity for the films is characterized using impedance spectroscopy. The room temperature conductivity for the PAN + 26 wt.%
LiCF3SO3 film and the PAN + 24 wt.% NaCF3SO3 film is 3.04 × 10−4 S cm−1 and 7.13 × 10−4 S cm−1, respectively. XRD studies show that the complexation that has occurred in the PAN containing salt films and complexes formed
are amorphous. The FTIR spectra results confirmed the complexation has taken place between the salt and the polymer. These
results correspond with surface morphology images obtained from SEM analysis. The conductivity–temperature dependence of the
highest conducting film from PAN + LiCF3SO3 and PAN + NaCF3SO3 systems follows Arrhenius equation in the temperature range of 303 to 353 K. The PAN containing 24 wt.% LiCF3SO3 film has a higher ionic conductivity and lower activation energy compared to the PAN containing 26 wt.%LiCF3SO3 film. These results can be explained based on the Lewis acidity of the alkali ions, i.e., the interaction between Li+ ion and the nitrogen atom of PAN is stronger than that of Na+ ion. 相似文献
182.
The Ba(Ce0.8Zr0.2)0.95Yb0.05O2.975 ceramics electrolyte was prepared via a Pechini method using metal nitrate salts as starting materials. An optimum annealing
temperature of 1,400 °C was needed to obtain a pure perovskite-like phase with orthorhombic structure. Particle size distribution
showed a bimodal distribution that corresponds to the loose powders and agglomerates size. Scanning electron micrograph revealed
that the loose powders were in the nanosize range (70–200 nm). These ultrafine loose powders enhanced the densification of
a pellet with relative density ∼95% obtained at 1,400 °C. The sample formed clear and compact grains with submicron sizes.
Impedance results showed that the impedance semicircle of the grain was observed only at T ≤ 250 °C. The introduction of 20 mol% Zr improved the chemical stability of BaCe0.95Yb0.05O2.975 sample in atmosphere containing carbon dioxide at 600 °C. The sample also exhibited high proton conductivity in wet hydrogen. 相似文献
183.
The interaction between capillary fluid films and micro-structural rough surfaces is one of the main challenges in studying self-cleaning mechanisms. The surface behavior of the deformable fluid film is governed by the Young-Laplace equation, which is highly non-linear. Therefore, a numerical solution is introduced using the finite element method, based on a continuum mechanical formulation. Surface and line contact at the fluid-structure interface are modeled by enforcing a contact constraint, and a contact angle, respectively. The numerical solution is validated against the analytical solution of a test case. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
184.
Motivated by the study of self-cleaning surfaces, the interaction between a spherical solid particle and a water droplet is studied on the microsale level, in terms of the balance forces and the surface properties. To define the forces acting on the solid-liquid interface, the meniscus depression is computed from the Young-Laplace equation, using a non-linear finite element formulation. The equilibrium force is derived in terms of the contact angle, particle size, and the penetration. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
185.
在三乙胺的作用下,N-芳基-马来酰亚胺分别与α-氯代9-吖啶甲醛肟和N-(N,N-对二甲氨基苯基)-C-(9-吖啶基)取代硝酮发生1,3-偶极环加成反应,合成了13个未见文献报道的新型3-(9-吖啶基)-5-芳基-3a,6a-二氢-4,6-二氧代氮杂茂并[3',4'-d]异噁唑啉衍生物3a~3f和2-(N,N-对二甲氨基苯基)-3-(9-吖啶基)-5-芳基-3a,6a-二氢-4,6-二氧代氮杂茂并[3',4'-d]异噁唑烷衍生物4a~4g,其结构经1HNMR,IR和元素分析确证.并对化合物3和4进行了初步药物活性筛选,其对HL-60人白血病细胞生长具有不同程度的抑制作用,但当样品浓度为10μmol/L时,抑制率为0~35%(IC5050%).化合物3f和4g对细胞分裂周期磷酸酯酶Cdc25A具有抑制作用:当样品浓度为20μg/mL时,其抑制率分别为50.90%和51.22%. 相似文献
186.
187.
Aysel Kantürk Figen Osman İsmail Sabriye Pişkin 《Journal of Thermal Analysis and Calorimetry》2012,107(3):1177-1189
Devolatilization behavior of several types of agricultural stalks (sunflower, rice, corn, and wheat) was studied using thermogravimetric
system (TG) under nitrogen atmosphere at different heating rates (10, 15, and 20 °C min-1). Coats&Redfern, Horowitz&Metzger, and Arrhenius non-isothermal kinetic models were applied to calculate the devolatilization
kinetic parameters and the devolatilization rate equations have been established. In addition, the kinetic compensation effect
(KCE) has also been used to correlate pre-exponential factor (k
o) with activation energy (E
a) and an existence of the KCE is accepted. TG-FT/IR analyses were applied of the different stalks and FT/IR stack plot used
to analyze the devolatilization gas products (CO2, CH4, HCOOH, CH3OH). Infrared vibrational frequencies, micro structure and crystallinity of stalks were investigated by Fourier transform
infrared spectroscopy (FT/IR), scanning electron microscope (SEM), and X-ray diffraction analysis (XRD), respectively. 相似文献
188.
β‐Amino alcohols derived from (1R,2S)‐norephedrine were synthesized and used as ligands in the catalytic enantioselective diethylzinc addition to benzaldehydes. N‐alkylated (1R,2S)‐norephedrine‐based derivative 3a gave the highest enantioselectivity. The effects of different parameters on the enantioselectivity of the product were investigated. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
189.
R. Alan Aitken Nouria A. Al‐Awadi Graham Dawson Osman El‐Dusouqui Kamini Kaul Ajith Kumar 《国际化学动力学杂志》2007,39(1):6-16
A series of five [(acetyl)(arylcarbabmoyl)methylene]triphenyl‐phosphoranes 1a–e and their thiocarbamoyl analogues 2a–e , [(alkoxycarbonyl)(arylcarbamoyl)methylene]triphenylphosphoranes 3a–e and their thiocarbamoyl analogues 4a–e were prepared and fully characterized. All ylides are found under conditions of flash vacuum pyrolysis to fragment giving arylisocyanate or isothiocyanate and acetyl ylides or alkoxy ylides which undergo thermal extrusion of Ph3PO. A kinetic study shows that these reactions are unimolecular and are of first‐order nature with no significant substituent effect. The thiocarbamoyl ylides 2 react from 4.6 to 42 times faster than their carbamoyl ylides 1 , while the thiocarbamoyl ylides 4 react from 6.6 to 20.9 times faster than their carbamoyl ylides 3 . © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 39: 6–16, 2007 相似文献
190.
The synthesis and characterization of nine coordination networks based on 1,3-bis(phenylthio)propane, L(3), and silver(I) salts of PF(6)(-) (1), CF(3)COO(-) (2), CF(3)CF(2)COO(-) (3), CF(3)CF(2)CF(2)COO(-) (4), p-TsO(-) (5, 6), and CF(3)SO(3)(-) (7-9) are reported. Only 1 and other "isostructural" complexes with weakly coordinating anions such as ClO(4)(-) and SbF(6)(-) are of the host-guest type. In all the other complexes, the anions and the acetone molecules, when present, are coordinated to the metal. Most of the complexes studied here form a 2D-coordination network. Only 4 and 5 adopt a polymer-like chain structure. The packing of the chains of 4 is pseudohexagonal compact, while that of 5 is of the centered type. In complex 1, the silver atom is tetrahedrally coordinated to the sulfur atoms of four different ligands. The PF(6)(-) anions and acetone molecules, sandwiched between silver-ligand cationic sheets, are held through van der Waals interactions. In each of the three perfluorocarboxylates (2-4), two silver atoms are joined by the anions in a diatomic bridging mode. The Ag...Ag distances are sufficiently short to indicate weak metal...metal interactions. The dimeric units in 2 and 3 are interconnected through the ligands, thereby generating a 2D-network of neutral sheets, while, in 4, the dimeric units are bound to four ligands and a 1D-coordination polymer is generated. In the case of the sulfonate anions (p-TsO(-) and CF(3)SO(3)(-)), the crystallization solvent influences the structure adopted. Thus, in 5, 7, and 9 obtained from petroleum ether, or other nonpolar solvents, two silver atoms are bound in a double-bridge fashion, while a monobridge mode is noted for 6 and 8, both recrystallized from diethyl ether. In 8, both bridging types are observed. The thermogravimetric investigation, in the room temperature-450 degrees C interval, of complexes 1, 3, and 7, which incorporate acetone molecules in their crystal structures, reveals a two-step weight loss for 1 (the acetone molecules are lost first followed by the ligands, leaving behind the silver salt), while complexes 3 and 7 decompose in a single step to metallic silver. 相似文献