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121.
T. Gamze Ulusoy Ghobadi Amir Ghobadi Merve Demirtas Muhammed Buyuktemiz Kubra N. Ozvural Elif Akhuseyin Yildiz Prof. Emre Erdem Prof. H. Gul Yaglioglu Prof. Engin Durgun Prof. Yavuz Dede Prof. Ekmel Ozbay Prof. Ferdi Karadas 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):8966-8976
The replacement of traditional ruthenium-based photosensitizers with low-cost and abundant iron analogs is a key step for the advancement of scalable and sustainable dye-sensitized water splitting cells. In this proof-of-concept study, a pyridinium ligand coordinated pentacyanoferrate(II) chromophore is used to construct a cyanide-based CoFe extended bulk framework, in which the iron photosensitizer units are connected to cobalt water oxidation catalytic sites through cyanide linkers. The iron-sensitized photoanode exhibits exceptional stability for at least 5 h at pH 7 and features its photosensitizing ability with an incident photon-to-current conversion capacity up to 500 nm with nanosecond scale excited state lifetime. Ultrafast transient absorption and computational studies reveal that iron and cobalt sites mutually support each other for charge separation via short bridging cyanide groups and for injection to the semiconductor in our proof-of-concept photoelectrochemical device. The reorganization of the excited states due to the mixing of electronic states of metal-based orbitals subsequently tailor the electron transfer cascade during the photoelectrochemical process. This breakthrough in chromophore-catalyst assemblies will spark interest in dye-sensitization with robust bulk systems for photoconversion applications. 相似文献
122.
An effective ant colony optimization algorithm (ACO) for multi-objective resource allocation problem (MORAP) 总被引:3,自引:0,他引:3
The multi-objective resource allocation problem (MORAP) addresses the important issue which seeks to find the expected objectives by allocating the limited amount of resource to various activates. Resources may be manpower, assets, raw material or anything else in limited supply which can be used to accomplish the goals. The goals may be objectives (i.e., minimizing costs, or maximizing efficiency) usually driven by specific future needs. In this paper, in order to obtain a set of Pareto solution efficiently, we proposed a modified version of ant colony optimization (ACO), in this algorithm we try to increase the efficiency of algorithm by increasing the learning of ants. Effectiveness and efficiency of proposed algorithm was validated by comparing the result of ACO with hybrid genetic algorithm (hGA) which was applied to MORAP later. 相似文献
123.
We study the dual problems associated with the robust counterparts of uncertain convex programs. We show that while the primal robust problem corresponds to a decision maker operating under the worst possible data, the dual problem corresponds to a decision maker operating under the best possible data. 相似文献
124.
Amir Norouzy Durdi Qujeq Mehran Habibi-Rezaei 《Reaction Kinetics and Catalysis Letters》2009,98(2):391-401
Acetylcholinesterase was immobilized by means of physical adsorption. The aim of this work is to describe the kinetic characterization
of the immobilized acetylcholinesterase. Here we report the effects of immobilization, carbaryl and its solvent dioxane on
the kinetic properties of acetylcholinesterase. The immobilized product has significant storage stability. Dioxane could decrease
the acetylcholinesterase activity and increase the inhibitory effect of carbaryl. Immobilization could change acetylcholinesterase
activity cooperatively. The inhibitory mechanism is hyperbolic noncompetitive. Carbaryl and dioxane could eliminate the substrate
inhibition by a competitive mechanism and by changing the native conformation of acetylcholinesterase. 相似文献
125.
Abd Elmoneim O. Elkhalifa Eyad Al-Shammari Mohd Adnan Jerold C. Alcantara Khalid Mehmood Nagat Elzein Eltoum Amir Mahgoub Awadelkareem Mushtaq Ahmad Khan Syed Amir Ashraf 《Molecules (Basel, Switzerland)》2021,26(12)
Abelmoschus esculentus (Okra) is an important vegetable crop, widely cultivated around the world due to its high nutritional significance along with several health benefits. Different parts of okra including its mucilage have been currently studied for its role in various therapeutic applications. Therefore, we aimed to develop and characterize the okra mucilage biopolymer (OMB) for its physicochemical properties as well as to evaluate its in vitro antidiabetic activity. The characterization of OMB using Fourier-transform infrared spectroscopy (FT-IR) revealed that okra mucilage containing polysaccharides lies in the bandwidth of 3279 and 1030 cm−1, which constitutes the fingerprint region of the spectrum. In addition, physicochemical parameters such as percentage yield, percentage solubility, and swelling index were found to be 2.66%, 96.9%, and 5, respectively. A mineral analysis of newly developed biopolymers showed a substantial amount of calcium (412 mg/100 g), potassium (418 mg/100 g), phosphorus (60 mg/100 g), iron (47 mg/100 g), zinc (16 mg/100 g), and sodium (9 mg/100 g). The significant antidiabetic potential of OMB was demonstrated using α-amylase and α-glucosidase enzyme inhibitory assay. Further investigations are required to explore the newly developed biopolymer for its toxicity, efficacy, and its possible utilization in food, nutraceutical, as well as pharmaceutical industries. 相似文献
126.
Jan Nisar Mukhtiar Ali Iftikhar Ahmad Awan Amir Badshah Sadullah Mir Rafaqat Ali Khan 《Reaction Kinetics and Catalysis Letters》2009,98(2):375-381
The gas-phase thermal decomposition of cis-2-methylcyclopropane carboxylic acid was investigated in the temperature range
692–753 K and pressure between 10 and 70 Torr. Arrhenius parameters were determined for homogeneous, unimolecular formation
of the isomeric products and for the overall loss-rate of the reactant. The determined values are in accordance with the Arrhenius
parameters that were reported previously for the thermal unimolecular reactions of cyclopropane and other substituted cyclopropanes.
The formation of isomeric products and the observed Arrhenius parameters are consistent with a biradical mechanism. The effect
of surface on the reaction was studied at 732 K using the packed reaction vessel. It was observed that the rate of production
of all isomeric products and the total loss of cis-2-methylcyclopropane carboxylic acid were not affected by increasing surface
to volume ratio. 相似文献
127.
128.
129.
Mansoureh Mohammadi Marzieh Kamankesh Zahra Hadian Amir Mohammad Mortazavian Abdorreza Mohammadi 《Chromatographia》2017,80(1):119-126
Microwave-assisted extraction and dispersive liquid–liquid microextraction followed by gas chromatography–mass spectrometry as a sensitive and efficient method was applied to extract and determine four biogenic amines (BAs) in Iranian Lighvan cheese samples. Carrez solutions were used for the sedimentation of proteins. Effective factors on the performance of microextraction were studied and optimized. The proposed method showed good linear ranges from 5 to 500 ng mL?1, with the coefficients of determination higher than 0.9929. Average recoveries were between 97 and 103%. Limits of detection for all analyzed BAs ranged from 5.9 to 14.0 ng g?1, and limits of quantitation ranged between 19.7 and 46.2 ng g?1. Compared with previous methods, the proposed method is simple, fast, accurate, and precise and gives low detection limits for investigating trace amounts of BAs in Iranian Lighvan cheese samples. The levels of four BAs were determined in five Lighvan cheese samples. Cadaverine was found as prevailing amine in the cheese samples. Putrescine, tyramine, and histamine were present at the second, third, and fourth highest levels, respectively. 相似文献
130.
S. Amir Aslanzadeh 《Journal of Structural Chemistry》2017,58(3):479-488
The effects of doping heteroatoms on the structure, electronic and adsorption properties of graphene are investigated using density functional theory calculations. Six different doped graphenes (with Al, B, Si, N, P, and S) are considered, and to obtain the interaction and adsorption properties, three sulfur-containing molecules (H2S, SO2, and thiophene) were interacted with selected graphenes. The adsorption energies (E ad) in the gas phase and solvents show the exothermic interaction for all complexes. The maximum E ad values are observed for aluminum doped graphene (AG) and silicon doped graphene (SiG), and adsorption energies in the solvent are not so different from those in the gas phase. NBO calculations show that the AG and SiG complexes have the highest E (2) interaction energies and simple graphene (G) and nitrogen doped graphene (NG) have the least E (2) energies. Population analyses show that doping heteroatoms change the energy gap. This gap changes more during the interaction and these changes make these structures useful in sensor devices. All calculated data confirm better adsorption of SO2 by graphenes versus H2S and thiophene. Among all graphenes, AG and then SiG are the best adsorbents for these structures. 相似文献