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161.
M. Rahiminezhad S. J. Shahtaheri M. R. Ganjali A. R. Koohpaei A. Rahimi Forushani F. Golbabaei 《Journal of Analytical Chemistry》2010,65(7):694-698
Diazinon imprinted sorbent can be a useful tool for selective enrichment, clean-up, and purification methods. In this study,
investigation of synthesis and evaluation of diazinon imprinted polymers has been performed using equilibrium binding experiments.
It is possible to use molecularly imprinted polymers as sorbents for anti-choline esterase (Anti-ChE) organophosphate pesticides (Ops). It has been found that MAA monomer is most suitable for the preparation of appropriate diazinon molecularly imprinted polymers
(MIPs). The type of porogen also influences the binding results. The best porogen for diazinon imprinting is chloroform due to
its poor hydrogen bonding capacity. 相似文献
162.
Saeed Bagherifam Amir Lakzian Seyed Javad Ahmadi Mohammad Farhad Rahimi Akram Halajnia 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(2):289-296
The influence of initial uranium concentration, solution pH, contact time and adsorbent mass was investigated for removal
of uranium from aqueous solutions by pine wood powder and wheat straw using a batch technique. The maximum removal efficiency
of uranium achieved at pH 8 and 7 for pine wood powder and wheat straw, respectively. Langmuir and Freundlich adsorption isotherms and three kinetic models of adsorption including; Elovich, Lagergren pseudo-first and Lagergren pseudo-second order were used to describe the adsorption mechanisms. The uranium sorption onto wood and wheat straw powders
followed a Freundlich isotherm. The kinetic studies showed that the data fitted very well to the pseudo-second order model in the studied concentration
range of uranium for both adsorbents. Uranium desorption from loaded adsorbents also studied using batch techniques as a function
of desorptive reagent, desorption time and desorptive reagent concentration. The results of the experiment indicated that
the optimum desorption efficiency of uranium for wood powder and wheat straw occurred in 5 min shaking time, using 1.5 M HNO3 and 2 M Na2CO3 solutions, respectively. 相似文献
163.
The kinematics of a magneto-rheological fluid droplet impact on a smooth surface, subjected to external magnetic field, was studied theoretically and experimentally. A time-dependent one-dimensional model of the impact, as typified by the droplet top center point height kinematics is developed. A series of experiments were conducted in order to validate the theoretical model. The shape changes generated during the impact process were recorded using a digital high-speed camera. Our novel kinematical model based on a variable damping function shows very good agreement with the experimental data for a wide range of Mason and Reynolds numbers. 相似文献
164.
In this article,we introduce the concept of entropy functional for continuous systems on compact metric spaces,and prove some of its properties.We also extract the Kolmogorov entropy from the entropy f... 相似文献
165.
166.
Kin Hong Liew Wan Zurina Samad Norazzizi Nordin Poh Lee Loh Joon Ching Juan Mohd Ambar Yarmo Badrul Hisham Yahaya Rahimi M. Yusop 《催化学报》2015,(5)
A new heterogeneous catalyst composed of Pd nanoparticles immobilized within a HypoGel resin has been prepared in the absence of any ligands using an extensive cross-linking method. This new-ly develop... 相似文献
167.
Optical and Quantum Electronics - Twin-core fiber optical tweezers (TCFOT) can be simulated using finite difference beam propagation method. We chose a tapered TCFOT and calculated its far-field... 相似文献
168.
A theoretical analysis of controllable metal–insulator transition is performed by carrying out a quantum chaos analysis for a single-walled carbon nanotube which is affected by topological Stone–Wales defect. Nanotubes have recently attracted attention as promising materials for flexible nanoelectronic devices. Individual topological Stone–Wales defects have been identified experimentally in carbon nanotubes (CNTs) and graphene. The findings reveal that defected CNT displays a gradual crossover from metal to insulator phase in a longitudinal electric field. By determining the threshold value of the electric field for metal–insulator transition, CNT may be used as a switch in electronic devices. Our results are obtained by calculating the singularity spectrum of a nearest-neighbor tight-binding model. Also, quantum chaos theory is used for obtaining a detailed understanding of a dynamic phase transition from delocalized states (chaotic) to localized states (Poisson). More interestingly, the appearance of negative differential resistance for pure CNT suggests potential applications in nanoelectronic devices. 相似文献
169.
Samane Jalali Mahmood Reza Rahimi Mehrorang Ghaedi Arash Asfaram Alireza Goudarzi 《应用有机金属化学》2018,32(1)
The present study deals with the synthesis and characterization (FE‐SEM, particle size distribution, XRD and point of zero charge) SnO2/(NH4)2‐SnCl6 nanocomposites loaded on activated carbon (SnO2/(NH4)2‐SnCl6‐NCs‐AC) and its subsequent application for the simultaneous removal of Methylene Blue (MB) and Orange G (OG) from aqueous solution. Response surface methodology (RSM) based on central composite design (CCD) give trend of influencing responses with respect to five parameters such as contact time (X1), OG concentration (X2), MB concentration (X3), adsorbent mass (X4) and pH (X5). In later stage following recognition of significant variables and interaction, quadratic model generated which are able to predict the dyes removal in different conditions. Justification and selection of significant terms was conducted based on analysis of variance and Fisher's F‐test Optimal value of contact time, OG concentration, MB concentration, adsorbent mass and pH were set at 4.0 min, 10 mg l?1, 20 mg L?1, 0.015 g and 6.0, respectively, which lead to achievement of best experiment removal percentage of 97.0 and 99.5% OG and MB respectively, from their binary solutions. The whole experimental data follow pseudo‐first‐order and pseudo‐second‐order rate equations. The fitting experimental data to more available conventional model like Langmuir, Freundlich, Temkin and Dubinin‐Radushkevich isotherm models revel more ability of Langmuir model (with R2 > 0.997) for explanation of system in equilibrium. The adsorption efficiency remained high even after the five cycle of reuse (99.76% and 95.56% for MB and OG, respectively). 相似文献
170.
Rahimi Z. Sarafraz H. Alahyarizadeh Gh. Shirani A. S. 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):431-442
Journal of Radioanalytical and Nuclear Chemistry - Magnetite CoFe2O4 nanoparticle and CoFe2O4/MWCNT nanocomposite adsorbents with high specific surface area, high adsorption capacity, and easily... 相似文献