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11.
Xun Tang Umamahesh Balijapalli Daichi Okada Buddhika S. B. Karunathilaka Chathuranganie A. M. Senevirathne Yi-Ting Lee Zhao Feng Atula S. D. Sandanayaka Toshinori Matsushima Chihaya Adachi 《Advanced functional materials》2021,31(43):2104529
Rationally manipulating the functional substituents plays a crucial role in tuning the luminescence and lasing properties of organic gain media. Herein, a cyanophenyl-moiety, which exhibits relatively weaker electron affinity, is connected to 2,6-dicarbonitrile diphenyl-1λ5-phosphinine (DCNP) via para-linking. Resultantly, the appreciated locally-excited characteristics ensuring a large oscillator strength and high radiative rate can be reserved in DCNP-4-(4-cyanophenyl) (DCNP-pCN). Interestingly, the weak charge-transfer state from the relative donor (D)/acceptor (A) interplay enables small singlet-triplet splitting (ΔEST ≈ 0.45 eV). Thus the triplets generated on DCNP-pCN can be efficiently scavenged by 4,4'-bis[(N-carbazole)styryl]biphenyl (BSBCz), which is used as the host with a lower-lying triplet energy level for DCNP-pCN. Moreover, benefitting from the mediation between the conjugated length extension and weak D/A interplay, the emission spectrum cannot be largely shifted, which can effectively suppress the overlap between the lasing emission of DCNP-pCN and the excited-state absorption of BSBCz, thereby avoiding detrimental singlet-triplet annihilation. Thus, high-quality distributed feedback lasings with ≈2.0 μJ cm−2 thresholds are achieved, and the organic light-emitting diodes exhibit external quantum efficiency exceeding 2.0% without efficiency rolloff under high current injection, indicating the potential for electrical-pumping organic lasings. 相似文献
12.
This paper proposes a new synthesis method for methanol as a future alternative fuel, by the combination of carbon supplied from wood and hydrogen supplied from the electrolysis of water using a solar power generation system in the desert. In the developed countries, more than half of the potential forest area has already been converted into other land uses, while existing forests are well organized and available for wood production. In the developing countries, potential forest sites are expected to be available for wood production, even though they are presently grasslands or secondary forests, while natural tropical forests will not be allowed to be converted into artificial forests. The area available for plantations within 500 km distant from deserts was estimated to be 65 Mha in the world, except for the mountain areas. Biomass production from these sites will be converted annually into 980 Mt methanol with hydrogen from the deserts. This amount is equal to 34% of the world's fuel consumption by vehicles. 相似文献
13.
14.
Protein has a complicated spatial structure, and has chemical and physical functions which originate from this structure.
It is important to predict the structure and function of proteins from a DNA sequence or amino acid sequence from the viewpoint
of biology, medical science, protein engineering, etc. However, to data there is no way to predict them accurately from these
sequences. Instead, some approaches attempt to estimate the functions based on an approximate similarity in the retrieval
of sequences. We propose a new method for the similarity retrieval of an amino acid sequence based on the concept of homology
retrieval using data compression. The introduction of compression by a dictionary technique enables us to describe the text
data as ann-dimensional vector usingn dictionaries, which is generated by compressingn typical texts, and enables us to classify the proteins based on their similarity. We examined the effectiveness of our proposal
using real genome data.
This work was presented in part at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, January 15–17,
2001 相似文献
15.
WANG Yong Toshinori Kojima LI Ming LIU Jie 《武汉理工大学学报(材料科学英文版)》2006,21(1):95-98
A super absorbent material was prepared with the super absorbent resin ( SAR ) and inorganic gel. The SAR of the carboxymethyl cellulose grafting acrylic acid ( CMC-AA ) was copolymer synthesized using the method of inverse-phase suspension polymerization. The influences of the monomer concentration, neutralization degree, the initiator, dispersion agent, cross-linking agent, reaction and drying temperature on the grafting copolymer properties were examined. Meanwhlie, its properties was investigated and the model for absorption mechanism of this absorbent composite was proposed. 相似文献
16.
Toshinori Kawabata Hoe I. Ling Yoshiyuki Mohri Daisuke Shoda 《Canadian Metallurgical Quarterly》2006,132(10):1354-1359
The existing design guidelines for buried flexible pipes are limited to depth up to 10?m. The increasing use of difficult terrains for infrastructure, landfills, and residential and industrial developments has prompted installation of drainage pipelines under 20–30?m high fills. This paper presents the behavior of an instrumented flexible pipe buried under a 47.1?m deep fill. For filling above 20?m, the measured vertical stress above the pipe exhibited a concave distribution, corresponding to 90 and 110% of the average vertical pressure at the center and edges of the pipe, respectively. The measured results suggest that a triangular lateral pressure distribution can lead to overly conservative and uneconomical results for high fills while Spangler’s analysis is unconservative. Based on the measured results, a revised vertical and lateral earth pressure diagram was proposed for the design of flexible pipe under high fills >20?m. This paper proposes closed-form analyses for estimating the moments and displacements of the pipe subjected to high fill earth pressures. These closed-form solutions agree well with the measured pipe displacements and strains. 相似文献
17.
Standard soil samples contaminated with various standard cyanocompounds were prepared. Column elution experiments and analyses were conducted. Compounds with an easy capacity for dissociation to ions, such as KCN and potassium hexacyanoferrate(III), were found to be eluted by forming free cyanide even in fresh water. Hexacyanoferrate(II) salts, such as potassium hexacyanoferrate(II) and iron(III) hexacyanoferrate(II), were found not to be dissociated in water, but were dissociated and diffused under alkaline conditions (pH >13). Hexacyanoferrate(II) ion was found to be more easily dissociated in water with a higher pH.Column tests as above were also conducted for soil samples taken from a former paint ink factory using iron(III) hexacyanoferrate(II), cyanogen chloride, potassium cyanate, copper cyanide, as well as potassium cyanide, as raw materials. It was demonstrate that iron(III) hexacyanoferrate(II) was dissociated and eluted under alkaline conditions. The elution rate was reduced when the contaminated soil was sandwiched with standard soil layers.Further, it was found that the Fe(CN)(6)(4-) ion eluted with NaOH from hexacyanoferrate acid in soil, were easily decomposed into cyanic acid or other byproducts by UV with the addition of ozone and H(2)O(2). 相似文献
18.
Fast agglomerative hierarchical clustering algorithm using Locality-Sensitive Hashing 总被引:1,自引:6,他引:1
Hisashi Koga Tetsuo Ishibashi Toshinori Watanabe 《Knowledge and Information Systems》2007,12(1):25-53
The single linkage method is a fundamental agglomerative hierarchical clustering algorithm. This algorithm regards each point
as a single cluster initially. In the agglomeration step, it connects a pair of clusters such that the distance between the
nearest members is the shortest. This step is repeated until only one cluster remains. The single linkage method can efficiently
detect clusters in arbitrary shapes. However, a drawback of this method is a large time complexity of O(n
2), where n represents the number of data points. This time complexity makes this method infeasible for large data. This paper proposes
a fast approximation algorithm for the single linkage method. Our algorithm reduces the time complexity to O(nB) by rapidly finding the near clusters to be connected by Locality-Sensitive Hashing, a fast algorithm for the approximate
nearest neighbor search. Here, B represents the maximum number of points going into a single hash entry and it practically diminishes to a small constant
as compared to n for sufficiently large hash tables. Experimentally, we show that (1) the proposed algorithm obtains clustering results similar
to those obtained by the single linkage method and (2) it runs faster for large data than the single linkage method.
Hisashi Koga received the M.S. and Ph.D. degree in information science in 1995 and 2002, respectively, from the University of Tokyo. From
1995 to 2003, he worked as a researcher at Fujitsu Laboratories Ltd. Since 2003, he has been a faculty member at the University
of Electro-Communications, Tokyo (Japan). Currently, he is an associate professor at the Graduate School of Information Systems,
University of Electro-Communications. His research interest includes various kinds of algorithms such as clustering algorithms,
on-line algorithms, and algorithms in network communications.
Tetsuo Ishibashi received the M.E. degree in information systems design from the Graduate School of Information Systems at the University
of Electro-Communications in 2004. Presently, he is a system engineer at Fujitsu Broad Solution & Consulting Inc.
Toshinori Watanabe received the B.E. degree in aeronautical engineering in 1971 and the D.E. degree in 1985, both from the University of Tokyo.
In 1971, he worked at Hitachi as a researcher in the field of information systems design. His experience includes demand forecasting,
inventory and production management, VLSI design automation, knowledge-based nonlinear optimizer, and a case-based evolutionary
learning system nicknamed TAMPOPO. He also engaged in FGCS (Fifth Generation Computer System) project of Japan and developed
a new hierarchical message-passing parallel cooperative VLSI layout problem solver that ran on PIM (Parallel Inference Machine)
in 1991. Since 1992, he has been a professor at the Graduate School of Information Systems, University of Electro-Communications,
Tokyo, Japan. His areas of interest include media analysis, learning intelligence, and the semantics of information systems.
He is a member of the IEEE. 相似文献
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