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81.
Gbolahan O. Shitta-Bey Mojtaba Mirzaeian Peter J. Hall 《Journal of Sol-Gel Science and Technology》2011,57(2):178-184
Organic gels have been synthesized by sol–gel polycondensation of phenol (P) and formaldehyde (F) catalyzed by sodium carbonate
(C). The effect of synthesis parameters such as phenol/catalyst ratio (P/C), solvent exchange liquid and drying method, on
the porous structure of the gels have been investigated. The total and mesopore volumes of the PF gels increased with increasing
P/C ratio in the range of P/C ≤ 8, after this both properties started to decrease with P/C ratio for P/C > 8 and the gel with
P/C = 8 showed the highest total and mesopore volumes of 1.281 and 1.279 cm3 g−1 respectively. The gels prepared by freeze drying possessed significantly higher porosities than the vacuum dried gels. The
pore volume and average pore diameter of the freeze dried gels were significantly higher than those of the vacuum dried gels.
T-butanol emerged as the preferred solvent for the removal of water from the PF hydrogel prior to drying, as significantly
higher pore volumes and specific surface areas were obtained in the corresponding dried gels. The results showed that freeze
drying with t-butanol and lower P/C ratios were favourable conditions for the synthesis of highly mesoporous phenol–formaldehyde
gels. 相似文献
82.
83.
Seyyed Mojtaba Mousavi Seyyed Alireza Hashemi Masoomeh Yari Kalashgrani Ahmad Gholami Yousef Mazaheri Mohsen Riazi Darwin Kurniawan Mohammad Arjmand O. Madkhali Mahmood D. Aljabri Mohammed M. Rahman Wei-Hung Chiang 《Chemical record (New York, N.Y.)》2024,24(1):e202200266
The ever-growing demand of human society for clean and reliable energy sources spurred a substantial academic interest in exploring the potential of biological resources for developing energy generation and storage systems. As a result, alternative energy sources are needed in populous developing countries to compensate for energy deficits in an environmentally sustainable manner. This review aims to evaluate and summarize the recent progress in bio-based polymer composites (PCs) for energy generation and storage. The articulated review provides an overview of energy storage systems, e. g., supercapacitors and batteries, and discusses the future possibilities of various solar cells (SCs), using both past research progress and possible future developments as a basis for discussion. These studies examine systematic and sequential advances in different generations of SCs. Developing novel PCs that are efficient, stable, and cost-effective is of utmost importance. In addition, the current state of high-performance equipment for each of the technologies is evaluated in detail. We also discuss the prospects, future trends, and opportunities regarding using bioresources for energy generation and storage, as well as the development of low-cost and efficient PCs for SCs. 相似文献
84.
Fatemeh Vahedi Mojtaba Sankian Malihe Moghadam Maryam Mohaddesfar Sirous Ghobadi Abdol Reza Varasteh 《Applied biochemistry and biotechnology》2011,163(7):895-905
Chenopodium album is a weedy annual plant in the genus Chenopodium. C. album pollen represents a predominant allergen source in Iran. The main C. album pollen allergens have been described as Che a 1, Che a 2, and Che a 3. The aim of this work was to clone the Che a 1 in Escherichia coli to establish a system for overproduction of the recombinant Che a 1 (rChe a 1). In order to clone this allergen, the pollens
were subjected to RNA extraction. A full-length fragment encoding Che a 1 was prepared by polymerase chain reaction amplification
of the first-strand cDNA synthesized from extracted RNA. Cloning was carried out by inserting the cDNA into the pET21b (+)
vector, thereafter the construct was transformed into E. coli Top10 cells and expression of the protein was induced by IPTG. The rChe a 1 was purified using histidine tag in recombinant
protein by means of Ni–NTA affinity chromatography. IgE immunoblotting, ELISA, and inhibition ELISA were done to evaluate
IgE binding of the purified protein. In conclusion, the cDNA for the major allergen of the C. album pollen, Che a 1, was successfully cloned and rChe a 1 was purified. Inhibition assays demonstrated allergic subjects sera
reacted with rChe a 1 similar to natural Che a 1 in crude extract of C. album pollen. This study is the first report of using the E. coli as a prokaryotic system for Che a 1 cloning and production of rChe a 1. 相似文献
85.
Mojtaba Amini Mina Bigdeli Sepideh Delsouz‐Hafshejani Arkady Ellern L. Keith Woo 《无机化学与普通化学杂志》2014,640(2):385-389
The reactions of FeCl3 · 6H2O and 2‐(2′‐hydroxyphenyl)‐2‐thiazoline as a bidentate O‐N donor thiazoline ligand (thoz) afford a five‐coordinate FeIII complex [Fe(thoz)2Cl] with a distorted square pyramidal configuration. Complex [Fe(thoz)2Cl] was isolated as air‐stable crystalline solids and fully characterized, including by single‐crystal X‐ray structure analysis. Complex [Fe(thoz)2Cl] shows very efficient reactivity in the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide (UHP) as the oxidant at room temperature in air. 相似文献
86.
Headspace solvent microextraction A new method applied to the preconcentration of 2-butoxyethanol from aqueous solutions into a single microdrop 总被引:1,自引:0,他引:1
A new procedure and experimental setup for the headspace solvent microextraction of volatile organic materials from aqueous sample solutions is described. The extraction occurs by suspending a 3-μl drop of the solvent from the tip of a microsyringe to the headspace of a stirred aqueous sample solution for a preset extraction time. The temperature of the microdrop and the bulk of sample solution should be kept constant at optimized values. The sample analyses were carried out by gas chromatography. The procedure was successfully applied to the extraction and determination of 2-butoxyethanol from content of some color samples used for painting the outer coverage of some machines such as coolers, refrigerator, cloths machine, etc. Parameters such as extraction time, nature of extraction solvent, size of microdrop, sample volume, stirring rate, ionic strength and pH of sample solution were studied and optimized, and the method performance was evaluated. 相似文献
87.
The peroxyoxalate-chemiluminescence arising from reaction of bis(2,4,6-trichlorophenyl)oxalate with hydrogen peroxide in the presence of a brightener Tinopal CBS (2,2′-((1,1′-biphenyl)-4,4′-diyldi-2.1-ethenediyl)bisbenzene sulfonic acid, disodium salt) has been studied. The relationship between the chemiluminescence intensity and concentrations of bis(2,4,6-trichlorophenyl)oxalate, sodium salicylate (as catalyst), hydrogen peroxide and Tinopal CBS is reported. The chemiluminescence parameters including intensity at maximum chemiluminescence, time at maximum intensity, total light yield, theoretical maximum level of intensity and pseudo-first-order rate constants for the rise and fall of the chemiluminescence burst (kr and kf) were evaluated from computer fitting of the resulting intensity-time plots. The activation parameters Ea, ΔH‡, ΔS‡ and ΔG‡ for the rise and fall steps were evaluated from the temperature dependence of kr and kf values. The results were discussed in terms of chemically initiated electron transfer between a reactive intermediate and Tinopal CBS as fluorescence activator. A possible mechanism involving dioxetanone derivatives as intermediates is proposed. Since there is a linear relationship between reciprocal of chemiluminescence intensity and reciprocal of fluorescer concentration, an analytical method based on partial least squares (PLS) regression was proposed for quantitative determination of Tinopal CBS. Satisfactory results were obtained with percent relative prediction error (RPE%) of 2.52 and detection limit of 2.7×10−5 M. 相似文献
88.
Zahra Talebpour Saeed Maesum Mehdi Jalali-Heravi Mojtaba Shamsipur 《Analytical sciences》2003,19(7):1079-1082
A 1H-NMR procedure based on an analysis of its data by a multivariate calibration method was conducted for the simultaneous determination of theophylline and caffeine in synthetic and real samples. Partial least squares regression (PLS) was chosen as the calibration method. The methyl signals of theophilline at 3.36 and 3.54 ppm that overlapped with those of caffeine were significant characteristics which were employed in this study for their analyses. The proposed method was successfully applied to recovery studies of theophylline and caffeine from real tablet samples. 相似文献
89.
Functionalization of gold cysteamine (Au? CA) self‐assembled monolayer with 4‐formylphenylboronic acid (BA) via Schiff's base formation, through in situ method to fabricate Au‐CA‐BA electrode is presented and described. The fabricated electrode was used as a novel sensor for accumulation and determination of dopamine (DA). The accumulation of DA as a diol on the topside of Au‐CA‐BA as a Lewis acid, was performed via esterification (Au? CA? BA? DA), and followed for determination of DA. Functionalization, characterization, and determination steps were probed by electrochemical methods like cyclic voltammetry and electrochemical impedance spectroscopy. The data will be presented and discussed from which a new sensor for DA is introduced. 相似文献
90.
Huge amounts of data in hyperspectral images have been caused to represent approaches for the band selection of these images.
In this paper, a new approach based on independent component analysis (ICA) is proposed. The idea of projection pursuit is
used to order the bands on the basis of a non-gaussianity distribution. Applying a negentropy function to weight bands is
a novel idea that leads to the selection of bands with minimum mutual information (MI) and besides maximum entropy, with respected
to the bands selected using other methods. 相似文献