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991.
992.
Textural and microstructural properties of Kradi cheese (an indigenous cheese of Jammu and Kashmir,India) 下载免费PDF全文
Hilal Ahmad Punoo Girdhari ramdas Patil Ram Ran Bijoy 《International Journal of Dairy Technology》2018,71(2):372-381
The texture and microstructure of Kradi cheese, an indigenous fresh unripened cheese of Jammu and Kashmir, India, were studied. There were significant differences (P < 0.05) for hardness, adhesiveness, springiness, cohesiveness, chewiness and resilience between samples from four different market areas. The optimised products made in the laboratory from cultures NCDC‐167 and NCDC‐144 showed significant differences (P < 0.05) in the textural and mechanical properties of tensile strength. The microstructure of the market samples was distinguished by the greater size of the voids present in three‐dimensional casein network. The optimised laboratory product had a more compact and fibrous structure compared to the market samples, which was attributed to its higher protein content. 相似文献
993.
Hyperspectral imaging as an effective tool for prediction the moisture content and textural characteristics of roasted pistachio kernels 总被引:1,自引:0,他引:1
Toktam Mohammadi-Moghaddam Seyed M. A. Razavi Masoud Taghizadeh Biswajeet Pradhan Ameneh Sazgarnia Ahmad Shaker-Ardekani 《Sensing and Instrumentation for Food Quality and Safety》2018,12(3):1493-1502
The objective of this study was to develop calibration models for prediction of moisture content and textural characteristics (fracture force, hardness, apparent modulus of elasticity and compressive energy) of pistachio kernels roasted in different conditions (temperatures 90, 120 and 150 °C; times 20, 35 and 50 min and air velocities 0.5, 1.5 and 2.5 m/s) using Vis/NIR hyperspectral imaging and multivariate analysis. The effects of different pre-processing methods and spectral treatments such as normalization [multiplicative scatter correction (MSC), standard normal variate transformation (SNV)], smoothing (median filter, Savitzky–Golay and Wavelet) and differentiation (first derivative, D1 and second derivative, D2) on the obtained data were investigated. The prediction models were developed by partial least square regression (PLSR) and artificial neural network (ANN). The results indicated that ANN models have higher potential to predict moisture content and textural characteristics of roasted pistachio kernels comparing to PLSR models. High correlation was observed between reflectance data and fracture force (R2?=?0.957 and RMSEP?=?3.386) using MSC, Savitzky–Golay and D1, compressive energy (R2?=?0.907 and RMSEP?=?15.757) using the combination of MSC, Wavelet and D1, moisture content (R2?=?0.907 and RMSEP?=?0.179) and apparent modulus of elasticity (R2?=?0.921 and RMSEP?=?2.366) employing combination of SNV, Wavelet and D1, respectively. Moreover, Vis–NIR data correlated well with hardness (R2?=?0.876 and RMSEP?=?5.216) using SNV, Wavelet and D2. These results showed the capability of Vis/NIR hyperspectral imaging and the central role of multivariate analysis in developing accurate models for prediction of moisture content and textural properties of roasted pistachio kernels. 相似文献
994.
Decision trees are among the best-known decision-making techniques and have been used extensively for both data analysis and predictive modeling.
BPM+ is a novel process modeling approach that helps represent business process models in a consistent and structured way to meet different stakeholders’
process representation needs. This paper reports on the outcomes of an ontological analysis of the potential use of decision-tree representations as a new
BPM+ perspective for the operational level of abstraction. This new perspective effectively demonstrates how a specialized/operational BPM stakeholder
perspective can be used to improve the existing organizational business process model repository. 相似文献
995.
In this work, the normalized Internal Model Control (IMC) filter time constant is designed to achieve a specified value of the maximum sensitivity for stable first and second order plus time delay process models, respectively. Since a particular value of the maximum sensitivity results in an almost constant percentage overshoot to controller setpoint change, an empirical relationship between the normalized IMC filter time constant and percentage overshoot is presented. The main advantage of the proposed method is that only a user-defined overshoot is required to design a PI/PID controller. Simulation examples are given to demonstrate the value of the proposed method. 相似文献
996.
Adikan FR Gawith CB Smith PG Sparrow IJ Emmerson GD Riziotis C Ahmad H 《Applied optics》2006,45(24):6113-6118
Experimental demonstration of small angle (0.8 degrees-5 degrees ) direct UV-written X couplers in silica-on-silicon is presented. Maximum and minimum coupling ratios of 95%(+/-0.8%) and 1.9% (+/-1%), respectively, were recorded. The structures also display very low polarization and wavelength dependence. A typical excess loss of 1.0 dB(+/-0.5 dB) was recorded. Device modeling using the beam propagation method and an analytical model showed good agreement with experimental results over a broad crossing angle and wavelength range. 相似文献
997.
Mehdi A Dourdain S Bardeau JF Reyé C Corriu RJ Gibaud A 《Journal of nanoscience and nanotechnology》2006,6(2):377-381
Optically transparent and highly ordered mesoporous organosilica thin films functionalized with two different organic groups in various proportions were synthesized by templated-directed cocondensation of tetraethylorthosilicate (TEOS) and a mixture of two distinct and functional organotriethoxysilanes [NC(CH2)3Si(OEt)3 and O=P(OEt)2(CH2)3Si(OEt)3]. The mesostructured films obtained by evaporation induced self-assembly (EISA) approach were deposited on glass or silicon substrates by dip-coating. They were characterized by Grazing Incidence Small Angle X-ray Scattering (GISAXS) and X-ray reflectivity. We showed that whatever the proportion in organic groups, only 2D hexagonal phase having p6m symmetry was observed for all the materials indicating a good compatibility between the organic groups. The bi-functionalization of the internal pores surface by the organotriethoxysilanes groups was clearly evidenced by using micro-Raman spectroscopy. 相似文献
998.
Akdogan EK Simon WK Safari A 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2006,53(12):2323-2332
Epitaxial and (110) oriented paraelectric thin films of Ba0.60Sro.40TiO3 were grown on (100) oriented NdGaO3 orthorhombic substrates, and the nonlinear dielectric properties were studied at 10 GHz along selected in-plane crystallographic directions in the film thickness range of 25-1200 nm. The measured dielectric properties show strong residual strain and in-plane directional dependence. For instance, the in-plane relative permittivity is found to vary from as much as 500 to 150 along [110] and [001], respectively, in the 600 nm film. Tunability was found to vary from as much as 54% to 20% in all films and directions. In a given film, the best tunability is observed along the compressed axis in a mixed strain state, 54% along [110] in the 600 nm film. It is shown that, by nanoscale manipulation of epitaxy and planar anisotropy, the return loss and phase shift in a paraelectric can be tuned over a rather wide range. The approach presented herein opens avenues for obtaining various degrees of phase shift on the same film, enabling one with an additional degree of freedom in device design and fabrication as well as multifunctionality. 相似文献
999.
Mondal PP Rajan K Ahmad I 《Journal of the Optical Society of America. A, Optics, image science, and vision》2006,23(7):1678-1686
Image filtering techniques have numerous potential applications in biomedical imaging and image processing. The design of filters largely depends on the a priori, knowledge about the type of noise corrupting the image. This makes the standard filters application specific. Widely used filters such as average, Gaussian, and Wiener reduce noisy artifacts by smoothing. However, this operation normally results in smoothing of the edges as well. On the other hand, sharpening filters enhance the high-frequency details, making the image nonsmooth. An integrated general approach to design a finite impulse response filter based on Hebbian learning is proposed for optimal image filtering. This algorithm exploits the interpixel correlation by updating the filter coefficients using Hebbian learning. The algorithm is made iterative for achieving efficient learning from the neighborhood pixels. This algorithm performs optimal smoothing of the noisy image by preserving high-frequency as well as low-frequency features. Evaluation results show that the proposed finite impulse response filter is robust under various noise distributions such as Gaussian noise, salt-and-pepper noise, and speckle noise. Furthermore, the proposed approach does not require any a priori knowledge about the type of noise. The number of unknown parameters is few, and most of these parameters are adaptively obtained from the processed image. The proposed filter is successfully applied for image reconstruction in a positron emission tomography imaging modality. The images reconstructed by the proposed algorithm are found to be superior in quality compared with those reconstructed by existing PET image reconstruction methodologies. 相似文献
1000.
Safinya CR Ewert K Ahmad A Evans HM Raviv U Needleman DJ Lin AJ Slack NL George C Samuel CE 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2006,364(1847):2573-2596
At present, there is an unprecedented level of interest in the properties and structures of complexes consisting of DNA mixed with oppositely charged cationic liposomes (CLs). The interest arises because the complexes mimic natural viruses as chemical carriers of DNA into cells in worldwide human gene therapy clinical trials. However, since our understanding of the mechanisms of action of CL-DNA complexes interacting with cells remains poor, significant additional insights and discoveries will be required before the development of efficient chemical carriers suitable for long-term therapeutic applications. Recent studies describe synchrotron X-ray diffraction, which has revealed the liquid crystalline nature of CL-DNA complexes, and three-dimensional laser-scanning confocal microscopy, which reveals CL-DNA pathways and interactions with cells. The importance of the liquid crystalline structures in biological function is revealed in the application of these modern techniques in combination with functional transfection efficiency measurements, which shows that the mechanism of gene release from complexes in the cell cytoplasm is dependent on their precise liquid crystalline nature and the physical and chemical parameters (for example, the membrane charge density) of the complexes. In [section sign] 5, we describe some recent new results aimed at developing bionanotube vectors for gene delivery. 相似文献