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101.
Minh Son Phan Étienne Baudrier Loïc Mazo Mohamed Tajine 《Journal of Mathematical Imaging and Vision》2017,57(2):164-182
This paper introduces a new method for estimating the angular difference between two tomographic projections belonging to a set of projections taken at unknown directions in 2D and 3D. Our method relies on the projection neighbor selection in projection moment space, the calculation of the angular differences between these neighboring projections using moment properties and a projection moment neighborhood graph. The accuracy and the robustness of our method are shown on a test database including fifty 2D and 3D gray-level images at different resolutions and with different levels of noise. 相似文献
102.
The objective of this work was to study the effects of washing and purification steps on qualitative and quantitative analysis of fecal stanols in the oyster Crassostrea gigas using either single or a combination of lipid purification steps on silica gel or aminopropyl bonded silica gel (NH2) or a washing step. Among the three analytical pathways compared, the two including water extraction or NH2 purification did not lead to higher recoveries and decreased repeatabilities of extractions compared to the single purification on silica gel. This latter led to similar recoveries (ca. 80 %) and repeatabilities (ca. 10 %) for both spiked standards (coprostanol and sitostanol). This analytical pathway has been applied to oysters collected in a harvesting area in Brittany (France) where fecal contaminations are important and allowed to quantify eight stanols in oysters. The relative proportions of fecal stanols of these oysters were combined with principal component analysis in order to investigate the usefulness of their stanol fingerprints to record a fecal contamination and to distinguish its source between human, porcine and bovine contaminations. Oysters non-fecally contaminated by Escherichia coli did not present specific stanol fingerprints while oysters fecally contaminated had a bovine fingerprint, suggesting a contamination of these samples by bovine sources. As a consequence, the method developed here allows the use of stanol fingerprints of oysters as a microbial source tracking tool that can be applied to shellfish harvesting areas subjected to fecal contaminations in order to identify the different sources of contamination and improve watershed management. 相似文献
103.
S. D. Palma B. Maletto P. Lo Nostro R. H. Manzo M. C. Pistoresi-Palencia D. A. Allemandi 《Drug development and industrial pharmacy》2013,39(7):821-827
ABSTRACT6-O-Ascorbic acid alkanoates (ASCn) are amphiphilic molecules having physical-chemical properties that depend on the alkyl chain length. The derivatives of low molecular weight (n < 11) have enough aqueous solubility to produce self-assemblies at room temperature (≈25°C), while those with longer alkyl chains possess a critical micellar temperature (CMT) higher than 30°C. At higher temperatures (T° > CMT), ASCn aqueous suspensions turn into either micellar solutions or gel phases, depending on the length of the hydrophobic chain. On cooling, coagels are produced, which possess a lamellar structure that exhibit sharp X-ray diffraction patterns and optical birefringence. The semisolid consistency of such coagels is an interesting property to formulate dermatological pharmaceutical dosage forms able to solubilize and stabilize different drugs. The objective of the present study was the evaluation of the enhancing permeation effect of ASCn with different chain lengths and to correlate permeability changes with histological effects. With this purpose, ASCn coagels containing anthralin (antipsoriasic drug) or fluorescein isothiocyanate (FITC, hydrophobic fluorescent marker) were assayed on rat skin (ex vivo) and mice skin (in vivo), respectively. Also, histological studies were performed aimed at detecting some possible side effects of ASCn. No inflammatory cellular response was observed in the skin when ASCn coagels were applied, suggesting non-irritating properties. Light microscopy indicated slight disruption and fragmentation of stratum corneum. The penetration of ASCn through rat skin epidermis was very fast and quantitatively significant. The permeation of anthralin was significantly increased when the drug was vehiculized in ASCn coagels, compared to other pharmaceutical systems. The results indicated that ASC12 seems to have the highest enhancing effect on FITC permeation. ASC12 appears to be the compound that possesses the highest capacity to enhance the penetration of the drugs. Furthermore, it has the highest permeation of the serie. 相似文献
104.
Hung‐Chieh Lo Po‐Yi Chou Chun‐Chieh Huang Po‐Jui Chen Shih‐Meng Hsu 《Water and Environment Journal》2014,28(3):442-448
Drawing from the lessons learnt from the Fukushima nuclear disaster in Japan, the assessment of subsurface environmental hazard around nuclear power plants has emerged as a critical task. Consequently, aiming to better understand the possible environmental impact of radiation leaks into the groundwater, a prescreening programme was initiated in 2011 by the Taiwanese government. As part of this programme, this study conducted various borehole prospecting techniques to identify in situ hydrogeological characteristics at Chin‐Shan Nuclear Power Plant. Borehole electrical log, sonic log and temperature/conductivity log were conducted to explain the regional lithologic conditions and permeability of the formation. In conjunction with this, the interwell tracer and pumping test was carried out to simultaneously determine the hydraulic parameters. In our opinion, the implementation of such in situ end‐to‐end investigations is essential in interpreting in situ fluid and solute transport dynamics prior to programming any numerical scheme for early warning, vulnerability assessment and regular monitoring of a nuclear power plant site. 相似文献
105.
The effects of conventional heating (C) or ohmic heating (O) treatment on the degradation of sugar and ascorbic acid (AA) were evaluated in chunky fruit desserts prepared with apple puree (Golden Delicious var.) and chunky peach (Panavi var.) pieces. Concentrations of 5-HMF, furfural (F), 3-hydroxy-2-pyrone (3H2P) and 2-furoic acid (FA) were determined to assess the importance of oxidative and/or thermal reactions during processing. Depending on the thermal processing, 5-HMF and F levels in samples ranged from not detected to 3260 and from not detected to 570 μg/100 g FW respectively. Production of 3H2P and FA ranged from 480 to 2670 and from 84 to 420 μg/100 g FW respectively. Results showed that the impact of final heating treatment on the formation of AA degradation products (3H2P and FA) was minor, if any. Thus, AA degradation during apple products processing mainly depended on oxidative reactions pathway. Likewise, ohmic heating processing had very little effect on the formation of 5-HMF and F, in opposite to conventional heating. 相似文献
106.
The electricity industry is rapidly changing: costs are increasingly dominated by capital and technology is turning loads into resources. This is similar to the early days of the Internet. Building on rate-structures used in the communications industry, utilities of the future should offer customers a portfolio of service contract options that provide a signal to the utility regarding the type and amount of infrastructure that should be deployed. 相似文献
107.
Giovanni Capurso Filippo Agresti Laura Crociani Gilberto Rossetto Benedetto Schiavo Amedeo Maddalena Sergio Lo Russo Giovanni Principi 《International Journal of Hydrogen Energy》2012
Several mixtures of LiBH4 and Mg(BH4)2 borohydrides in different stoichiometric ratios (1:0, 2:1, 1:1, 1:2, 0:1), prepared by high energy ball milling, have been investigated with X-ray powder diffraction and thermal programmed desorption (TPD) volumetric analysis to test the dehydrogenation kinetics in correlation with the physical mixture composition. Afterwards mixed and unmixed borohydrides were dispersed on high specific surface area ball milled graphite by means of the solvent infiltration technique. BET and statistical thickness methods were used to characterize the support surface properties, and SEM micrographs gave a better understanding of the preparation techniques. It has been observed by TPD volumetric measurements that the confinement of the reactive borohydrides on the nanoporous supports leads to a lower dehydrogenation temperature compared to unsupported borohydrides. Moreover, a further decrease of the dehydrogenation temperature has been observed by increasing the specific surface area of the support and the pores volume and by using the prepared mixtures instead of pure materials. The dehydrogenation process seems to be favoured by the heterogeneous nucleation on the graphite surface of decomposition products or intermediate phases from melted liquid borohydrides. 相似文献
108.
The better compression rate can be achieved by the traditional vector quantization (VQ) method, and the quality of the recovered image can also be accepted. But the decompressed image quality can not be promoted efficiently, so how to balance the image compression rate and image recovering quality is an important issue. In this paper, an image is transformed by discrete wavelet transform (DWT) to generate its DWT transformed image which can be compressed by the VQ method further. Besides, we compute the values between the DWT transformed image and decompressed DWT transformed image as the difference matrix which is the adjustable basis of the decompressed image quality. By controlling the deviation of the difference matrix, there can be nearly lossless compression for the VQ method. Experimental results show that when the number of compressed bits by our method is equal to the number of those bits compressed by the VQ method, the quality of our recovered image is better. Moreover, the proposed method has more compression capability comparing with the VQ scheme. 相似文献
109.
Information system development can be considered a collaboration between users and developers. The inability to leverage the localized knowledge embedded in these two stakeholders hinders software development work to achieve high performance. Exploring the ways to counter this difficulty is then critical. This study applies an intellectual capital perspective to address the issues around spanning the knowledge boundary between developers and users. Our findings highlighted how important effective knowledge boundary spanning is to both product and project quality. Furthermore, three dimensions of intellectual capital increased the degree to which knowledge boundary spanning was effective. 相似文献
110.
Lo?c Petigny Sandrine Périno Matteo Minuti Francesco Visinoni Jo?l Wajsman Farid Chemat 《International journal of molecular sciences》2014,15(5):7183-7198
Microwave extraction and separation has been used to increase the concentration of the extract compared to the conventional method with the same solid/liquid ratio, reducing extraction time and separate at the same time Volatile Organic Compounds (VOC) from non-Volatile Organic Compounds (NVOC) of boldo leaves. As preliminary study, a response surface method has been used to optimize the extraction of soluble material and the separation of VOC from the plant in laboratory scale. The results from the statistical analysis revealed that the optimized conditions were: microwave power 200 W, extraction time 56 min and solid liquid ratio of 7.5% of plants in water. Lab scale optimized microwave method is compared to conventional distillation, and requires a power/mass ratio of 0.4 W/g of water engaged. This power/mass ratio is kept in order to upscale from lab to pilot plant. 相似文献