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91.
In this study, thin films of Ag deposited onto glass substrates were etched using inductively coupled fluorine-based plasmas. The effects of various process conditions on the Ag etch characteristics were evaluated to ascertain whether it would be possible to etch patterned Ag films with high etch rates and smooth sidewalls free of involatile etch products. It was found that involatile etch products remained on the substrate when films were etched in CF4-based gas mixtures possessing either O2 or N2 as an additive. However, when Ar was added to either NF3 or CF4, a residue-free etch was obtained provided the partial pressure of Ar was no less than 50%. It is proposed that the residue-free Ag etch mechanism involves the formation of silver fluoride, which is physically sputtered by Ar+ ions. A Ag etch rate of 160 nm/min with a Ag to photoresist etch selectivity exceeding 1.1 was achieved with an inductive power of 1500 W, a d.c. bias voltage of −180 V and a chamber pressure of 0.8 Pa with 50-50 CF4/Ar partial pressures obtained with 60 sccm CF4/60 sccm Ar flows. In addition, these conditions produced smooth Ag sidewall etch profiles. 相似文献
92.
The central effect of 3-morpholinosydnonimine, a nitric oxide donor, on the sympatho-adrenomedullary system was investigated in urethane-anesthetized rats. Intracerebroventricular administration of 3-morpholinosydnonimine (100, 250 and 500 microg/animal) induced a marked elevation of adrenaline levels and a slight elevation of noradrenaline levels in the plasma. These 3-morpholinosydnonimine (250 microg/animal)-induced elevations of catecholamines were abolished by intracerebroventricular treatments with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-l-oxyl 3-oxide (750 microg/animal), a nitric oxide scavenger, and indomethacin (500 microg/animal), a cyclo-oxygenase inhibitor, but not with superoxide dismutase (250 units/animal), a superoxide anion scavenger. Furthermore, the 3-morpholinosydnonimine (250 microg/animal)-induced elevation of plasma adrenaline levels was abolished by intracerebroventricular treatments with thromboxane A2 synthase inhibitors [furegrelate (100, 250 and 1000 microg/animal) and carboxyheptyl imidazole (500 microg/animal)], and also with thromboxane A2 receptor blockers [(+)-S-145 (100, 250 and 1000microg/animal) and SQ29548 (8microg/animal)]. The elevation of noradrenaline levels was, however, not attenuated by these thromboxane A2-related test agents. The present results indicate that nitric oxide but not peroxynitrite markedly activates central adrenomedullary outflow. Thromboxane A2 in the brain is probably involved in this central activation of adrenomedullary outflow. 相似文献
93.
Yang B. Kang Y.M. Lee S.S. Noh K.H. Lee S.W. Kim N.K. Kweon S.Y. Yeom S.J. Park Y.J. 《Electron Device Letters, IEEE》2002,23(12):743-745
We report on highly reliable characteristics of 1-Mb ferroelectric memories based on 0.35-/spl mu/m CMOS technology ensuring ten-year retention and imprint at 175/spl deg/C, which have been successfully developed for the first time. This excellent reliability resulted from newly developed [Bi/sub 1-x/La/sub x/]/sub 4/Ti/sub 3/O/sub 12/ (BLT) ferroelectric films with superior reliability performance at high temperatures, and also resulted from robust integration schemes free from ferroelectric degradation due to process impurities such as moisture and hydrogen. 相似文献
94.
Kyung-Whan Yeom 《Microwave Theory and Techniques》1998,46(8):1165-1168
The 900-MHz-band voltage-controlled oscillator (VCO) currently used in a commercial mobile-communication handset has the features of light weight, small size, low phase noise, and low DC current consumption. This paper investigates the problems that may occur when these types of VCO's are employed in next-generation high-frequency mobile-communication handsets. The results show that oscillation may not commence above frequency fT/2 √(Req /Tbb), which is significantly below the fmax of the device itself, due to the effects of the circuit elements. In addition, a new formula is proposed which provides a practical guideline for selection of the active devices. The procedure for extraction of the small-signal model required by the proposed formula is also described in detail. The results obtained with the formula are in good agreement with those obtained from the measured S-parameters 相似文献
95.
Electrical characteristics of NOT and NAND logic circuits fabricated using top-gate ZnO nanowire field-effect transistors (FETs) with high-k?Al(2)O(3) gate layers were investigated in this study. To form a NOT logic circuit, two identical FETs whose I(on)/I(off) ratios were as high as ~10(8) were connected in series in a single ZnO nanowire channel, sharing a common source electrode. Its voltage transfer characteristics exhibited an inverting operation and its logic swing was?98%. In addition, the characteristics of a NAND logic circuit composed of three top-gate FETs connected in series in a single nanowire channel are discussed in this paper. 相似文献
96.
Han Eol Lee Seungjun Kim Jongbeom Ko Hye‐In Yeom Chun‐Won Byun Seung Hyun Lee Daniel J. Joe Tae‐Hong Im Sang‐Hee Ko Park Keon Jae Lee 《Advanced functional materials》2016,26(34):6170-6178
Flexible transparent display is a promising candidate to visually communicate with each other in the future Internet of Things era. The flexible oxide thin‐film transistors (TFTs) have attracted attention as a component for transparent display by its high performance and high transparency. The critical issue of flexible oxide TFTs for practical display applications, however, is the realization on transparent and flexible substrate without any damage and characteristic degradation. Here, the ultrathin, flexible, and transparent oxide TFTs for skin‐like displays are demonstrated on an ultrathin flexible substrate using an inorganic‐based laser liftoff process. In this way, skin‐like ultrathin oxide TFTs are conformally attached onto various fabrics and human skin surface without any structural damage. Ultrathin flexible transparent oxide TFTs show high optical transparency of 83% and mobility of 40 cm2 V?1 s?1. The skin‐like oxide TFTs show reliable performance under the electrical/optical stress tests and mechanical bending tests due to advanced device materials and systematic mechanical designs. Moreover, skin‐like oxide logic inverter circuits composed of n‐channel metal oxide semiconductor TFTs on ultrathin, transparent polyethylene terephthalate film have been realized. 相似文献
97.
Improvement of electron field emission from carbon nanotubes by Ar neutral beam treatment 总被引:1,自引:0,他引:1
To improve the field emission properties of screen printed carbon nanotube (CNT) films, an Ar neutral beam was used as one of the surface treatment techniques and the CNT field emission characteristics after the treatment were compared with those after Ar ion beam treatment. The Ar neutral beam treatment enhanced the field emission properties of the CNTs and by decreasing the turn-on field and by increasing emission sites. When the field emission properties were measured after the treatment for 10 s with an energy of 100 eV, the turn-on field decreased from 1.7 to 0.9 V/μm while that after the ion beam treatment increased from 1.7 to 2.8 V/μm showing damage of exposed CNTs due to the intensive bombardment by the positive ions in the beam. The neutral beam treatment appeared to expose more CNT field emitters from the CNT paste without cutting or severely damaging the already exposed long CNT emitters because there were no charged particles in the beam. 相似文献
98.
The Wave Characteristics of Two-Phase Flows Predicted by HLL Scheme Using Interfacial Friction Terms
Wave propagation in the two-phase flows has been numerically investigated. The waves have been generated by various means such as two-phase shock tube, pressure pulse, and void pulse wave. The six compressible two-fluid conservation laws with the interfacial friction terms are solved in the two fractional steps. The first PDE operator step makes use of analytic eigenvalues of an approximate Jacobian matrix in HLL scheme. The second source operator step makes use of the stiff ODE solver in a semi-implicit form. The waves in the two-phase flow field resolved by the present method have shown very small numerical diffusion. An assessment is made on the effect of interfacial friction terms included in the formulation. 相似文献
99.
In this article, a numerical method to solve the two-set, eight-equation, compressible, two-fluid, two-phase flow model is developed in two dimensions as an extension of the earlier one-dimensional version. The multidimensional two-fluid model can be effectively solved by a finite-volume method in a rotated reference frame. In order to estimate the fastest wave speeds in the hyperbolic equation system for the Harten–Lax–van Leer (HLL) scheme, we first regard the liquid phase as compressible by taking the stiffened-gas equation of state. Then we derive the two-dimensional approximate Jacobian matrix and obtain the associated eight analytic eigenvalues. Using the HLL scheme, we solve a few two-phase flow problems including shape cavitation and underwater explosion, demonstrating application of the present numerical method to meaningful problems. 相似文献
100.
Jeeyeon Kim Youngjae Kim Prof. Jinsung Tae Miyoung Yeom Prof. Bongjin Moon Dr. Xi‐Ping Huang Prof. Bryan L. Roth Kangho Lee Dr. Hyewhon Rhim Prof. Il Han Choo Prof. Youhoon Chong Dr. Gyochang Keum Dr. Ghilsoo Nam Prof. Hyunah Choo 《ChemMedChem》2013,8(11):1855-1864
The 5‐HT7 receptor (5‐HT7R) is a promising therapeutic target for the treatment of depression and neuropathic pain. The 5‐HT7R antagonist SB‐269970 exhibited antidepressant‐like activity, whereas systemic administration of the 5‐HT7R agonist AS‐19 significantly inhibited mechanical hypersensitivity and thermal hyperalgesia. In our efforts to discover selective 5‐HT7R antagonists or agonists, aryl biphenyl‐3‐ylmethylpiperazines were designed, synthesized, and biologically evaluated against the 5‐HT7R. Among the synthesized compounds, 1‐([2′‐methoxy‐(1,1′‐biphenyl)‐3‐yl]methyl)‐4‐(2‐methoxyphenyl)piperazine ( 28 ) was the best binder to the 5‐HT7R (pKi=7.83), and its antagonistic property was confirmed by functional assays. The selectivity profile of compound 28 was also recorded for the 5‐HT7R over other serotonin receptor subtypes, such as 5‐HT1R, 5‐HT2R, 5‐HT3R, and 5‐HT6R. In a molecular modeling study, the 2‐methoxyphenyl moiety attached to the piperazine ring of compound 28 was proposed to be essential for the antagonistic function. 相似文献