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151.
Energy Storage: Confined Assembly of Hollow Carbon Spheres in Carbonaceous Nanotube: A Spheres‐in‐Tube Carbon Nanostructure with Hierarchical Porosity for High‐Performance Supercapacitor (Small 19/2018)
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152.
Masoud Ebrahimzadeh Sari Granroth Sami Vuori Marko Punkkinen Mikko Miettinen Risto Punkkinen Mikhail Kuzmin Pekka Laukkanen Mika Lastusaari Kalevi Kokko 《Advanced Engineering Materials》2023,25(19):2300762
Manufacturing a low-resistive Ohmic metal contact on p-type InP crystals for various applications is a challenge because of the Fermi-level pinning via surface defects and the diffusion of p-type doping atoms in InP. Development of wet-chemistry treatments and nanoscale control of p-doping for InP surfaces is crucial for decreasing the device resistivity losses and durability problems. Herein, a proper combination of HCl-based solution immersion, which directly provides an unusual wet chemical-induced InP(100)c(2 × 2) atomic structure, and low-temperature Mg-surface doping of the cleaned InP before Ni-film deposition is demonstrated to decrease the contact resistivity of Ni/p-InP by the factor of 10 approximately as compared to the lowest reference value without Mg. Deposition of the Mg intermediate layer on p-InP and postheating of Mg/p-InP at 350 °C, both performed in ultrahigh-vacuum (UHV) chamber, lead to intermixing of Mg and InP elements according to X-ray photoelectron spectroscopy. Introducing a small oxygen gas background (O2 ≈ 10−6 mbar) in UHV chamber during the postheating of Mg/p-InP enhances the indium outdiffusion and provides the lowest contact resistivity. Quantum mechanical simulations indicate that the presence of InP native oxide or/and metal indium alloy at the interface increases In diffusion. 相似文献
153.
Nima Taghipour Mariona Dalmases Guy L. Whitworth Miguel Dosil Andreas Othonos Sotirios Christodoulou Shanti Maria Liga Gerasimos Konstantatos 《Advanced materials (Deerfield Beach, Fla.)》2023,35(1):2207678
The use of colloidal quantum dots (CQDs) as a gain medium in infrared laser devices has been underpinned by the need for high pumping intensities, very short gain lifetimes, and low gain coefficients. Here, PbS/PbSSe core/alloyed-shell CQDs are employed as an infrared gain medium that results in highly suppressed Auger recombination with a lifetime of 485 ps, lowering the amplified spontaneous emission (ASE) threshold down to 300 µJ cm−2, and showing a record high net modal gain coefficient of 2180 cm−1. By doping these engineered core/shell CQDs up to nearly filling the first excited state, a significant reduction of optical gain threshold is demonstrated, measured by transient absorption, to an average-exciton population-per-dot 〈Nth〉g of 0.45 due to bleaching of the ground state absorption. This in turn have led to a fivefold reduction in ASE threshold at 〈Nth〉ASE = 0.70 excitons-per-dot, associated with a gain lifetime of 280 ps. Finally, these heterostructured QDs are used to achieve near-infrared lasing at 1670 nm at a pump fluences corresponding to sub-single-exciton-per-dot threshold (〈Nth〉Las = 0.87). This work brings infrared CQD lasing thresholds on par to their visible counterparts, and paves the way toward solution-processed infrared laser diodes. 相似文献
154.
在经典的模式识别理论中,Viterbi算法代表了统计概率的模式匹配算法,而DTW算法代表了模版匹配的模式匹配算法,它们之间是否存在关系至今尚无定论.为了找到这两种算法之间的关系,在类别隶属度是广义概率的假设前提下,应用模糊数学的理论在Viterbi算法与DTW算法之间建立起联系.首先,提出了利用模糊数学的贴近度把DTW算法的距离向Viterbi算法的概率转化的通用贴近度表达式,并对通用贴近度表达式给出了理论上的证明.其次,应用DTW的通用贴近度表达式重估HMM参数,建立DTW算法与Viterbi算法之间的模糊贴近度关系,并为此提出了δ-ε算法,得到基于数据帧的类似于HMM的参数重估形式.然后,为了确保建立DTW算法与Viterbi算法之间的模糊贴近度关系的正确性,以定理的形式给出了相应的证明.再次,通过设定的DTW贴近度表达式对HMM参数重估的过程中,发现了DTW贴近度的重估参数与HMM重估参数之间存在着的模糊关系,以定理的形式对这种模糊关系加以证明.最后,依据上述定理提出了Dtw-ViterbiⅠ,Ⅱ,Ⅲ算法,以定理的形式对Dtw-ViterbiⅠ,Ⅱ,Ⅲ算法的正确性加以证明,并将对Dtw-ViterbiⅠ... 相似文献
155.
156.
Pradipta K. Nayak Jongsu Jang Changhee Lee Yongtaek Hong 《Journal of the Society for Information Display》2010,18(8):552-557
Abstract— The effects of lithium (Li) doping concentration and gate dielectrics on the performance of solution‐processed zinc‐oxide (ZnO) thin‐film transistors (TFTs) has been investigated. ZnO films with strong c‐axis orientation and lower background conductivity was obtained with 15 at.% of Li. Different crystallization behavior of ZnO was observed in the case of various dielectric surfaces. The 15‐at.% Li‐doped ZnO films (thickness ~20 nm) prepared on SiO2 and SiNx were found to be present in crystalline form, whereas the film prepared on aluminum titanium oxide (ATO) was found to be amorphous. A field‐effect mobility of 1.81 cm2/V‐sec and an Ion/Ioff ratio of 2 × 106 were obtained for the 15‐at.% Li‐doped ZnO TFTs with a bilayer gate dielectric of SiO2 and SiNx. The comparison of dielectric studies showed that the performance of TFTs prepared on SiNx and ATO are higher than that of the TFTs prepared on SiO2. 相似文献
157.
传统吉祥图案是中华民族文化千百年来沉淀的结果,是广大劳动人民集体的智慧与创造,是中华民族思想文化得以传承的源泉。时代的发展、变迁,物质条件及生活方式的改变,人们的观念意识和审美情趣也在不断的发生变化,与之相生相伴的各种艺术形式也都打上了鲜明的时代烙印。传统吉祥图案纹饰,变化万千,可以让我们看出当时的时代风尚,将这些传统吉祥图案认真总结,可将它归纳出主要的几种类型。 相似文献
158.
Chander ShekharAuthor VitaeK.I. GnanasekarAuthor Vitae E. PrabhuAuthor VitaeV. JayaramanAuthor Vitae T. GnanasekaranAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):19-27
Indium oxide (In2O3) doped with 0.5-5 at.% of Ba was examined for their response towards trace levels of NOx in the ambient. Crystallographic phase studies, electrical conductivity and sensor studies for NOx with cross interference for hydrogen, petroleum gas (PG) and ammonia were carried out. Bulk compositions with x ≤ 1 at.% of Ba exhibited high response towards NOx with extremely low cross interference for hydrogen, PG and ammonia, offering high selectivity. Thin films of 0.5 at.% Ba doped In2O3 were deposited using pulsed laser deposition technique using an excimer laser (KrF) operating at a wavelength of (λ) 248 nm with a fluence of ∼3 J/cm2 and pulsed at 10 Hz. Thin film sensors exhibited better response towards 3 ppm NOx quite reliably and reproducibly and offer the potential to develop NOx sensors (Threshold limit value of NO2 and NO is 3 and 25 ppm, respectively). 相似文献
159.
160.
Message-passing is a key ingredient of concurrent programming. The purpose of this paper is to describe the equivalence between the proof theory, the categorical semantics, and term calculus of message-passing. In order to achieve this we introduce the categorical notion of a linear actegory and the related polycategorical notion of a poly-actegory. Not surprisingly the notation used for the term calculus borrows heavily from the (synchronous) π-calculus. The cut-elimination procedure for the system provides an operational semantics. 相似文献