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111.
Russian Journal of Applied Chemistry - Page 1646, Figure 8 should be replaced by the following:  相似文献   
112.
Journal of Solid State Electrochemistry - Different carbon paste electrodes were prepared from carbonaceous materials including multi-walled carbon nanotubes (functionalized and pristine form),...  相似文献   
113.
Journal of Inclusion Phenomena and Macrocyclic Chemistry - In this work, a new macrocyclic cadmium complex, [Cd(ACE)I]2[CdI4] (1); ACE: 1,3,6,10,12,15-hexaazatricyclo[13.3.1.16,10]eicosane, was...  相似文献   
114.
The novel metal–organic framework Co2(bdda)1.5(OAc)1·5H2O (UoB‐3) was synthesized via a simple method at room temperature. UoB‐3 was characterized by the different methods, including X‐ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT‐IR), N2‐adsorption/desorption and elemental analysis. The catalytic ability of UoB‐3 was detected to be excellent for primary and secondary alcohols oxidation reaction with high yields under solvent‐free conditions. Moreover, UoB‐3 was highly active for Henry reaction of different aldehydes with nitromethane in water as a green solvent. The nanocatalyst can be recycled for five consecutive cycles without losing its activity and structural rigidity. The antibacterial activity of UoB‐3 nanostructures towards Gram‐negative bacteria, Escherichia coli and Gram‐positive bacteria, Bacillus cereus was also evaluated by using an inhibition zone test. These nanostructures exhibited strong antibacterial effect against both of them. The purpose of this study was the developing metal–organic framework materials with the enhanced activity in various fields.  相似文献   
115.
An improvement of lithium‐ion batteries with regard to their reversible capacity, cycling stability, rate performance, and safety under repetitive charge and discharge still requires considerable research activity. However, graphite has remained the unexcelled material for the anode so far. Here, it is shown that two novel quaternary lithium‐chalcogenidometalate phases, Li4MnGe2S7 ( 1 ) and Li4MnSn2Se7 ( 2 ), represent very promising new anode materials for lithium‐ion cells in that they achieve specific lithium storage capacities higher than that of the commercially used graphite, and display an excellent stability during cycling. These properties are based on the structural peculiarities of the phases, which adopt Wurtzite‐related topologies and provide high structural flexibility of the metal sulfide or selenide bonds as advantageous pre‐requisitions for a large ion accessible volume.  相似文献   
116.
The development of a biosensor based on the immobilization of horseradish peroxidase (HRP) within a zirconium alkoxide-polyetilenimine film onto screen-printed electrodes (SPE) for acetaminophen detection and acetaminophen quantification in pharmaceutical products is described. The biosensor operation mode is based on monitoring the amperometric signal produced by the electrochemical reduction of the enzymatically generated electroactive oxidized species of acetaminophen in the presence of hydrogen peroxide. The enzyme immobilization is performed by retention in a polyethylenimine-zirconium alcoxide porous gel film, a technique that offers good entrapping and a protective environment for the biocomponent due to the hydration properties of the immobilization layer. SPEs have the advantage of being easily mass-produced at low costs with superior characteristics in comparison with classical electrode materials. In this configuration, zirconium alkoxide demonstrates its electrocatalytic activity. The biosensor allows the quantification of acetaminophen with a limit of detection of 6.21×10?8 M and a linear range between 4.35×10?7 M and 4.98×10?6 M. Finally, the biosensor is applied to the quantitative analysis of acetaminophen in Perdolan® tablets.
  相似文献   
117.
The ignition and combustion of coal particles are investigated numerically under conventional and oxy-fuel atmospheres. Devolatilization is computed using the chemical percolation devolatilization (CPD) model. The CPD model is coupled with a Lagrangian particle tracking method in the framework of a multiphysics, multiscale Navier–Stokes solver. Combustion in the gas phase is described using finite rate chemistry. The numerical results for ignition are compared with available experimental data and a remarkably good agreement is observed. The effect on flame ignition of the different phases characterizing the release of volatile gases is assessed. These different phases manifest themselves in two distinct peaks in the devolatilization rate and it is observed that ignition can occur during the first volatile release or on the onset of the second, depending on the particle size and gas temperature. It is found that an increase of ignition delay time in oxy-atmosphere compared to the air case is related to the depletion of radicals that react with the abundant carbon dioxide of the oxy-atmosphere, while the increased heat capacity of the mixture does not play a role.  相似文献   
118.
119.
Myogenic autoregulation of cerebral blood flow is one of the mechanisms affecting cerebral hemodynamics. Short or long-lasting changes in intracranial pressure (ICP) are believed to reveal the responses of the cerebral system to myogenic stimuli. Through the incorporation of a theoretical model into the experimental measurements of cerebrovascular distensibility and compliance in patients with traumatic brain injury (TBI), the current study is an attempt to explain ICP dynamics in either presence or absence of cerebral autoregulation. The pulse wave velocity and transfer function between arterial blood pressure and ICP were utilized as the major tools to reflect variations in the mechanical properties of distant cerebral artries/arteriols. The results imply that different states of cerebral autoregulation and associated regimes within the cerebrovascular system can lead to different types of interrelationship between the slow variations of ICP, cerebral arterial distensibility, and compliance. Consequently, each of these classes may require different types of treatment on patients with TBI.  相似文献   
120.
A novel ligand‐free synthesis of alkynyl hydrazones via coupling reaction of hydrazonyl chlorides and terminal alkynes, catalyzed by CuI led to excellent yields.  相似文献   
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