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91.
Quantum Dots: Perovskite Quantum Dots with Near Unity Solution and Neat‐Film Photoluminescent Quantum Yield by Novel Spray Synthesis (Adv. Mater. 7/2018) 下载免费PDF全文
92.
As the dimensions of devices are shrunk quickly, the requirements of metallization become more critical. For VIA barrier and seeding layer filling and deposition, the process was mostly applied with the copper physical vapor deposition methodology in the back-end of line flow of the interconnection metallization. The criteria for barrier and seeding layer deposition are the metal continuity inside the VIA feature and grain size and orientation control for film diffusion barrier and qualities. Besides, while the interconnection size shrunk to nano-scale, the barrier thickness would be very thinner to maintain the VIA resistance; however, it would face the film conformity and continuity consistence within the wafer and different features. The integration solution would be developed and studied with the re-sputter process step adding into the convectional physical vapor deposition process. The resputter process step could not only improve the film conformity and continuity in the VIA's sidewall; but also reduce the resistance of VIA feature over 20%. The improvement of the resputter method adding into the deposition process would be contributed to the standard barrier deposition in the nano-scale feature of the interconnect. Besides, we also discussed the effect of the film properties after the resputter process introduced into the barrier deposition. 相似文献
93.
A side-polished multimode fiber sensor based on surface plasmon resonance (SPR) as the transducing element with a halogen light source is proposed. The SPR fiber sensor is side polished until half the core is closed and coated with a 37 nm gold thin film by dc sputtering. The SPR curve on the optical spectrum is described by an optical spectrum analyzer and can sense a range of widths in wavelengths of SPR effects. The measurement system using the halogen light source is constructed for several real-time detections that are carried out for the measurement of the index liquid detections for the sensitivity analysis. The sensing fiber is demonstrated with a series of refractive index (RI) liquids and set for several experiments, including the stability, repeatability, and resolution calibration. The results for the halogen light source with the resolution of the measurement based on wavelength interrogation were 3 x 10(-6) refractive index units (RIUs). The SPR dip shifted in wavelength is used as a measure of the RI change at a surface, and this RI change varies directly with the number of biomolecules at the surface. The SPR dip shift in wavelength, which was hybridized at 0.1 microM of the target DNA to the probe DNA, was 8.66 nm. The all-fiber multimode SPR sensor, which has the advantages of being low cost, being disposable, having high stability and linearity, being free of labeling, and having potential for real-time detection, permit the sensor and system to be used in biochemical sensing and environmental monitoring. 相似文献
94.
Various cutting techniques are available to drill holes, but drilling is the most common way in secondary machining of composite materials owing to the need for structure joining. Twist drills are widely used in the industry to produce holes rapidly and economically. Since the twist drill has a chisel edge, increasing the length of a chisel edge will result in an increase in the thrust force generated. Whereas, a saw drill has no chisel edge; it utilizes the peripheral distribution of the thrust force for drilling. As a result, the saw drill can achieve better a machining quality in drilling composite laminates than twist drill. The deviation of cutting edge that occurs in saw drill would result in an increase of thrust force during drilling, causing delamination damage when drilling composite materials in particular. A comprehensive model concerning delamination induced by the thrust force of a deviation saw drill during drilling composite materials has been established in the present study. For a deviation saw drill, the critical thrust force that triggers delamination increases with increasing β. A lower feed rate has to be used with an increasing deviation saw drill in order to prevent delamination damage. The results agree with real industrial experience. A guide for avoiding the drill deviation during drill regrinding or drill wear has been proved analytically by the proposed model, especially when the deviation ratio (β) affects the critical thrust force. This approach can be extended to examine similar deviation effects of various drills. 相似文献
95.
We report the Schottky performance and thermal reliability of a wide bandgap InGaP layer in contact with a Cu/Au metallic
system. An effective Schottky barrier height of 0.97 eV and an ideality factor of 1.21 can be achieved. The thermal reliability
of the resultant Schottky barrier diodes was analyzed using Auger electron spectroscopy and atomic force microscopy. The thermal
reliability could be main tained up to 450°C. The failure mechanism was attributable to the decomposition of the InGaP layer
and the interdiffusion of the chemical elements at higher temperature. Insensitive photoresponsivity with the in cident optical
power was found for the resultant Au/Cu-metal-semiconductor-metalphotodetectors (MSM-PDs). According to the measured temporal
response of the Au/Cu-MSM-PDs, the operation frequency could be above 10 GHz. 相似文献
96.
Chung-Ya Tsao Wei-Hsing Tuan Kuei-Chih Feng 《International Journal of Applied Ceramic Technology》2019,16(5):2094-2100
In this study, relationships between the processing, microstructure, and properties of barium niobate (Ba5Nb4O15) are investigated. The milling of a Ba5Nb4O15 powder in water is effective with respect to size reduction. However, after milling in water, BaCO3 is formed within the slurry. With the increase in the amount of BaCO3 formed, the aspect ratio of the elongated Ba5Nb4O15 grains increases. The formation of the elongated Ba5Nb4O15 grains prohibits the densification. Hence, the microwave dielectric properties, including permittivity and quality factor, are poor because of the low density. In addition, milling in ethanol is carried out for comparison: A lower amount of BaCO3 is formed after milling in ethanol; the extent of anisotropic grain growth is thus reduced. 相似文献
97.
Szu-Hsien Chen Ching-Ting Tsao Chih-Hao Chang Yi-Ting Lai Ming-Fung Wu Ching-Nan Chuang Hung-Chia Chou Chih-Kuang Wang Kuo-Haung Hsieh 《Materials science & engineering. C, Materials for biological applications》2013,33(5):2584-2594
Wound dressings of chitosan are biocompatible, biodegradable, antibacterial and hemostatic biomaterials. However, applications for chitosan are limited due to its poor mechanical properties. Here, we conducted an in vivo mouse angiogenesis study on reinforced poly(ethylene glycol) (PEG)-chitosan (RPC) hydrogels. RPC hydrogels were formed by cross-linking chitosan with PEGs of different molecular weights at various PEG to chitosan ratios in our previous paper. These dressings can keep the wound moist, had good gas exchange capacity, and was capable of absorbing or removing the wound exudate. We examined the ability of these RPC hydrogels and neat chitosan to heal small cuts and full-thickness skin defects on the backs of male Balb/c mice. Histological examination revealed that chitosan suppressed the infiltration of inflammatory cells and accelerated fibroblast proliferation, while PEG enhanced epithelial migration. The RPC hydrogels promoted wound healing in the small cuts and full layer wounds. The optimal RPC hydrogel had a swelling ratio of 100% and a water vapor transmission rate (WVTR) of about 2000 g/m2/day. In addition, they possess good mechanical property and appropriate degradation rates. Thus, the optimal RPC hydrogel formulation functioned effectively as a wound dressing and promoted wound healing. 相似文献
98.
99.
Study on the Stability of Ion-exchange Resin Catalysts:Ⅰ. TGA as a Rapid Evaluating Method 总被引:1,自引:1,他引:0
Wilbert Tsao 《中国炼油与石油化工》2010,(2)
The thermal stability of five commercial ion-exchange resin catalysts was studied by means of thermal gravimetric analysis(TGA) at elevated temperatures of up to 600℃and isothermal temperatures in the range of 150℃and 200℃.Resin samples with different initial water contents were also investigated.The study indicated that TGA,as a complementary evaluating method for the plug flow reactor system approach,could be used as a fast analyzing means for study on the thermal stability of ion-exchange resin cataly... 相似文献
100.
This study presents a rapid and simple approach for creating silicon nanostructures using metal-assisted etching. The thickness of the metal layer was found to be a key process parameter affecting the surface morphology of silicon nanostructures. Au and Ag layers with a thickness of 3 nm, 5 nm, and 10 nm were used to study the effects of metal catalyst thickness on silicon nanostructure morphology. The experimental results show that the surface morphology of metal has a significant influence on the silicon nanostructure morphology, such that the silicon nanostructures transform from porous silicon surfaces into filament nanostructures or silicon nanowire with increasing thicknesses of both the Au and Ag metal layers. 相似文献