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111.
测定了竹豆营养保健米的Zn,Cu,Fe,Mn,Se含量,作了营养评分,并对该型保健米的科学配膳进行了研究,为改革主食营养结构,防治疾病提供了依据。  相似文献   
112.
As a continuation of a recent study of commercial wood charcoals as far as their potential production of carbon adsorbents is concerned, we have studied the influence of the final heating temperature (T) as carbonization variable in the range 250–1000 °C on the yield and on the characteristics of granular chars prepared from two very different charcoals: a holm-oak charcoal manufactured by partial combustion in a charcoal kiln and an eucalyptus charcoal industrially manufactured in a continuous furnace. Our study also includes the changes produced in both charcoals heated at 250 °C in air for 24 h, and their influences on the adsorption of water vapour at 25 °C. The samples were characterized by thermogravimetry, chemical analyses, Fourier transform infrared spectroscopy, densimetric measurements and mercury porosimetry. T affects the char yield, the chemical composition and the porosity of each char series differently. In particular, the total open pore volumes (to helium) of the starting charcoals, 0.475 and 1.044 cm3 g−1, increase to 0.872 and 1.293 cm3 g−1 heating up to 1000 and 500 °C, respectively. The changes by carbonization are mainly due to devolatilization; moreover, a moderate structural shrinkage occurs heating the eucalyptus charcoal at T > 500 °C. Concerning the air treatments, the yields do not present a significant difference; carbonyl groups are formed and the resulting pore structures depend on the starting charcoals. Water adsorption is larger for the eucalyptus carbons (approximately type V isotherms) than for the holm-oak carbons (type II isotherms).  相似文献   
113.
In this study, benzylated bamboo flour (BBF) was synthesized using benzyl chloride under mild conditions. This material can be added to medium density polyethylene (MDPE) as a reinforcing filler material. The crystal structure and properties of the BBF and corresponding BBF/MDPE panels were investigated by Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, energy dispersive X‐ray spectroscopy, mechanical tests and surface hydrophobicity measurements, and the obtained results are in good agreement. According to the scanning electron microscopy and X‐ray diffraction investigations, the crystal structure of the bamboo material disappeared after the addition of benzyl chloride. The Fourier transform infrared spectroscopy analysis provided further evidence for the successful benzylation. The intensity of the bands attributed to the O—H stretching or deformation vibrations decreased, and the intensity of the bands attributed to the C = O and C—O bonds in the benzyl group increased, which was confirmed by the X‐ray spectroscopy analysis. The volume fraction of the dispersed phase increased dramatically, and the interfacial fusion between the BBF particles and the MDPE matrix improved. The tensile strength and flexural strength of the prepared BBF/MDPE panels were up to 24.21% and 26.73% higher, respectively, compared with panels fabricated from unmodified bamboo flour. Furthermore, the surface hydrophobicity was found to be higher, which confirmed the good interface fusion. The strengthening mechanism is discussed in this paper, and the overall results suggest that BBF is a promising candidate material for the substitution of traditional wood fibers and unmodified bamboo flour in wood plastic composites. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
114.
From the viewpoint of material and structure in the design of bamboo blades of large-scale wind turbine, a series of mechanical property tests of bamboo laminates as the major enhancement materials for blades are presented. The basic mechanical characteristics needed in the design of bamboo blades are brie?y introduced. Based on these data, the aerodynamic-structural integrated design of a 1.5 MW wind turbine bamboo blade relying on a conventional platform of upwind, variable speed, variable pitch, and doubly-fed generator is carried out. The process of the structural layer design of bamboo blades is documented in detail. The structural strength and fatigue life of the designed wind turbine blades are certified. The technical issues raised from the design are discussed. Key problems and direction of the future study are also summarized.  相似文献   
115.
In this paper, the use of petung bamboo (Dendrocalamus asper) as an alternative material for the top plate of acoustic guitars was evaluated. In the first research stage, the analysis was carried out on petung bamboo splits, which were treated with three different preservation conditions, namely unpreserved, preserved by boiling in water and preserved by boiling in a solution of 5% borax and boric acid. The vibration damping ratios and the sound radiation coefficients of these three types of splits were measured. It was found that their vibration damping ratios were not significantly different, whereas the sound radiation coefficient of the petung bamboo splits preserved in borax and boric acid was 40–60% higher than the other two variants. Based on this result, in the second research stage, three acoustic guitars with top plates from the borax–boric acid preserved petung bamboo, spruce, and pine were constructed. The top plate frequency response function of the three guitars was evaluated. Here, the spruce guitar was used as a reference for the generally preferred guitar sound characteristics, whereas the pine guitar was included as a sample of guitar made from local Indonesian wood. The results showed that the frequency response function of the petung bamboo guitar were generally five times lower than that of the spruce guitar, but two times higher than that of the pine guitar. The response amplitudes of the bamboo guitar were significantly higher than those of the spruce and pine guitars for frequencies between 200 and 400 Hz. Based on the results, it is concluded that petung bamboo has the potential to be applied as an alternative material for guitar top plates. However, since the bamboo guitars exhibits different resonances, the produced sound will have distinctive characteristics compared to the sound from guitars with spruce top plates.  相似文献   
116.
Bamboo charcoal coated with silver (BC/Ag) was prepared by activation and chemical reduction processes at different AgNO3 contents (10‐30 wt.%). The spectroscopic characterizations of the formation processes of BC/Ag composites were studied using X‐ray diffraction, scanning electron microscopy and transmission electron microscopy. These composites were introduced in epoxy resin to be a microwave absorber and mixed polyethylene to be an infrared stealth plate. Microwave absorbing properties were investigated by measuring complex permittivity, complex permeability and reflection loss in the 2‐18 and 18‐40 GHz microwave frequency range using the free space method. The thermal extinction measurements in the 3‐5 and 8‐12 μm were done to evaluate the shielding affectivity of infrared. The results showed that a significant thermal extinction and a wider absorption frequency range could be obtained by adding silver to bamboo charcoal.  相似文献   
117.
The aim of this work was to understand if solvent contaminants can interfere in Suzuki’s cross-coupling reactions and if it can explain the lack of robustness in industrial processes. For this purpose, several parameters were tested on the industrial model reaction between 2-bromonaphthalene and phenylboronic acid catalyzed by Pd/C. Best results were obtained using THF as solvent. Traces of the precursors of the used solvents, such as 2,3-dihydrofurane or maleic anhydride (100–300 ppm related to the solvent) strongly poisoned the reaction, decreasing the conversion significantly. This means that to ensure robust production, solvent quality must be analyzed at the ppm level. Fortunately, addition of triphenylphosphine can circumvent the catalyst poisoning.  相似文献   
118.
In recent years, bamboo charcoal, a new kind of material with special microporous and biological characteristics, has attracted great attention in many application fields. In this paper, the potential of bamboo charcoal to act as a solid-phase extraction (SPE) adsorbent for the enrichment of the environmental pollutant perfluorooctanoic acid, which is one of the newest types of persistent organic pollutants in the environment, has been investigated. Important factors that may influence the enrichment efficiency—such as the eluent and its volume, the flow rate of the sample, the pH of the sample and the sample volume—were investigated and optimized in detail. Under the optimum conditions, the limit of detection for PFOA was 0.2 ng L−1. The experimental results indicated that this approach gives good linearity (R 2 = 0.9995) over the range 1–1000 ng L−1 and good reproducibility, with a relative standard deviation of 4.0% (n = 5). The proposed method has been applied to the analysis of real water samples, and satisfactory results were obtained. The average spiked recoveries were in the range 79.5∼118.3 %. All of the results indicate that the proposed method could be used for the determination of PFOA at ultratrace levels in water samples.  相似文献   
119.
Recently, environmental disruption is proceeding on a global scale through the consumption of huge amounts of fossil fuels and the emission of various chemical substances. However, these substances resist bio-treatment. TiO2 generates electrons and holes by irradiation with light. Most organic micro-pollutants, including dioxins, are decomposed into carbon dioxide and water by the effect of the holes with high oxidative potential. By using such a photocatalytic reaction, various applications are feasible for environmental cleanup. In general, TiO2 powder has been utilized as photocatalyst, although TiO2 powder photocatalyst has several disadvantages: (1) it is difficult to handle, (2) photocatalytic reaction is slow and it takes a lot of time for treatment and (3) it is difficult to apply to plastics and textiles, because the photocatalyst decomposes them. We have developed a photocatalyst suitable for practical use and have developed high-activity photocatalysts such as TiO2 photocatalytic transparent film, photocatalytic silica-gel, apatite-coated TiO2 photocatalyst usable for plastics and textiles, photocatalytic paper, photocatalytic blue charcoal and photocatalytic oxygen scavenger. The application of these high-activity photocatalysts has been studied in deodorization, anti-bacterial, self-cleaning, anti-stain, water treatment, air purification such as photocatalytic decomposition of dioxins and VOC, and NO x removal. Now various photocatalytic articles using these new photocatalyst materials are on the market in Japan. Photocatalytic technology can create many valuable products for environmental use all over the world.  相似文献   
120.
Phytochemistry of fruits and leaves of the unique bamboo Melocanna baccifera resulted in the isolation of 27 secondary metabolites, including 4-Oxabicyclo[3.2.2]nona-1(7),5,8-triene and Verbacine. Biological activity studies of Verbacine revealed it as an inhibitor of acetylcholinesterase and as cytotoxic against C6 cancer cells.  相似文献   
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