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71.
For a signal control road network subject to equilibrium flows, the maximum possible increase in travel demands is considered in this paper. Using the concept of reserve capacity of signal-controlled junctions, the problem of finding the maximum increase in traffic demands can be formulated as a mathematical program with equilibrium constraints (MPEC). In this paper, we present a projected gradient approach to obtain the maximum increase in travel demands based on the TRANSYT traffic model. Numerical computations are made on a grid network where good results are obtained. 相似文献
72.
Huey-Liang Hwang Yan-Kai Chiou Chen-Chan Wang Tai-Bor Wu Minghwei Hong Chun-Yuan Lu Fu-Chien Chiu Joseph Ya-Min Lee 《Applied Surface Science》2007,254(1):236-241
It is well known that Taiwan's IC industry is in the very leading front of the world, and production of 65 nm devices was launched in 2006. Within a few years, the need of high-k dielectrics and metal gates is eminent and truly indispensable. Professor H.L. Hwang (the author) organized 12 professors and 50 graduate students of National Tsing Hua University and Chiao Tung University, and executed this particular project, which is sponsored by the Ministry of Economic Affairs of Republic of China, and is aimed at treating efficiently this problem and transferred the critical technologies to industry in a time frame of 3 years. 相似文献
73.
Double-exponentiation is a crucial arithmetic operation for many cryptographic protocols. Several efficient double-exponentiation algorithms based on systolic architecture have been proposed. However, systolic architectures require large circuit space, thus increasing the cost of the protocol. This would be a drawback when designing circuits in systems requiring low cost and low power consumption. However, some cost savings can be attained by compromising speed, as in portable devices and many embedded systems. This study proposes a scalable and systolic AB
2 and a scalable and systolic A × B, which are the core circuit modules of double-exponentiation. A scalable and systolic double-exponentiation can thus be obtained based on the proposed scalable AB
2 and A × B architecture. Embedded system engineers may specify a target double-exponentiation with appropriate scaling systolic circuits. The proposed circuit has lower circuit space/cost and low time/propagation than other circuits. 相似文献
74.
K. Asokan O. Peña L. Le Polles J. C. Jan J. W. Chiou W. F. Pong 《Journal of Cluster Science》2009,20(1):205-211
The rare-earth based molybdenum chalcogenides, REMo6Se8 (RE = rare-earth metals) have been extensively studied because of their unique crystal structure based on Mo6Se8 clusters and their outstanding properties involving coexistence of superconductivity and magnetism. Among all these compounds,
Ce and Eu based chalcogenides are magnetic and non-superconductors and possess many novel properties. Understanding their
electronic structure is likely to provide valuable information about these materials. We employ X-ray absorption near-edge
structure (XANES) spectroscopy at Mo and Se K-edges of EuMo6Se8 to identify the local environment respectively around Mo and Se ions and XANES spectra at L3-edge of Eu ion to identify their valence state. Results from this study demonstrate that Se ions in EuMo6Se8 are in two inequivalent sites and the valency of Eu is divalent. 相似文献
75.
J.-L. Wang Y.-S. Lai B.-S. Chiou C.-C. Chou C.-C. Tsai T.G.-Y. Lee H.-C. Cheng 《Applied Physics A: Materials Science & Processing》2007,89(1):213-219
The physical and electrical properties of (Pb,Sr)TiO3 (PSrT) films annealed by various techniques are systematically investigated in this study. The crystallinity and ferroelectricity
of PSrT films can be enhanced by excimer laser annealing (ELA), but the effect only works on the upper region of films. On
the other hand, PSrT films treated by rapid thermal annealing (RTA) can also improve crystallinity and ferroelectricity. However,
the leakage current of films is seriously increased due to defects and interfacial diffusion induced by post-RTA at high temperature.
As a result, the laser-assisted two-step annealing (post-ELA+RTA) is proposed in this work. It is found that PSrT films treated
by post-ELA+RTA show improved crystallinity, better ferroelectric properties, higher dielectric constant, and lower leakage
currents, which bring out the longer lifetime and higher breakdown field.
PACS 77.84.-s; 81.40.Ef; 42.62.-b 相似文献
76.
The Waste Isolation Pilot Plant (WIPP) is a deep underground geological repository for defense transuranic wastes. The creation of a full baseline radiological standard for the WIPP underground is essential in order to evaluate and account for the influence of the naturally occurring radioactive materials, and to prepare for any suspected contamination or the very unlikely event of a real accident scenario. In this report, we describe the establishment of the baseline information using the gamma background dose rate measurements and the salt rib smears of surface removable alpha and beta activities throughout the WIPP underground. The average background gamma dose rate in the WIPP underground is 8.27 x 10(-9) +/- 1.65 x 10(-9) Gy/h while the gamma dose rate on the WIPP surface is 3.46 x 10(-8) +/- 1.65 x 10(-9) Gy/h. The overall surface average alpha activity in the underground is 8.52 x 10(-5) +/- 1.22 x 10(-4) Bq/cm2 (at 1sigma level) with the minimum detectable activity (MDA) of 4.81 x 10(-4) Bq/cm2. The overall surface average beta activity is 8.25 x 10(-4) +/- 8.17 x 10(-4) Bq/cm2 (at 1sigma level) with the MDA of 3.19 x 10(-3) Bq/cm2. This baseline standard will be beneficial to the overall WIPP operational facility, ensuring the worker safety and adding to public confidence in the operation of the WIPP. 相似文献
77.
Chiou SJ Innocent J Riordan CG Lam KC Liable-Sands L Rheingold AL 《Inorganic chemistry》2000,39(19):4347-4353
The syntheses and molecular structures of a series of tetrahedral zinc complexes designed to model the active sites in Escherichia coli methionine synthases are reported. [PhTttBu]ZnBr (PhTttBu = phenyltris((tert-butylthio)-methyl)borate) was prepared and characterized crystallographically to provide entry into [S3]ZnX complexes. Metathesis with KSPh yielded the phenylthiolato complex, [PhTttBu]Zn(SPh), which represents a structural mimic of the homocysteine ligated form of the enzyme. Alternatively, [S2N]ZnX (X = Br, CH3, SPh) species were prepared using the new mixed-donor ligands, [Ph(pz)BttBu] (phenyl(pyrazolyl)bis((tert-butylthio)methyl)borate) and [Ph(pztBu)BttBu] (phenyl(3-tert-butylpyrazolyl)bis((tert- butylthio)methyl)borate). Protonolysis of [Ph(pztBu)-BttBu]Zn(CH3) by PhSH in toluene yielded [Ph(pztBu)BttBu]Zn(SPh), a synthetic analogue of the homocysteine ligated form of cobalamin-independent methionine synthase (Met E). The average Zn-S bond distance in [Ph-(pztBu)BttBu]Zn(SPh) of 2.37 A compares well with the EXAFS-derived distance of 2.31 A found in the homocysteine-bound form of Met E. 相似文献
78.
79.
[reaction: see text] Treatment of 7-oxa- and 7-azabenzonorbornadienes with terminal acetylenes in the presence of Ni(dppe)Cl2, ZnCl2, and Zn powder in toluene at 90 degrees C afforded the corresponding cis-2-alkynyl-1,2-dihydronaphthalene derivatives in moderate to excellent yields with remarkably high stereoselectivity. 相似文献
80.
Sheng‐Huei Hsiao Jiun‐Hsiang Chiou 《Journal of polymer science. Part A, Polymer chemistry》2001,39(13):2262-2270
A series of poly(o‐hydroxy amide)s having both ether and sulfone linkages in the main chain were synthesized via the low‐temperature solution polycondensation of 4,4′‐[sulfonylbis(1,4‐phenylene)dioxy]dibenzoyl chloride and 4,4′‐[sulfonylbis(2,6‐dimethyl‐1,4‐phenylene)dioxy]dibenzoyl chloride with three bis(o‐aminophenol)s including 4,4′‐diamino‐3,3′‐dihydroxybiphenyl, 3,3′‐diamino‐4,4′‐dihydroxybiphenyl, and 2,2‐bis(3‐diamino‐4‐hydroxyphenyl)hexafluoropropane. Subsequent thermal cyclodehydration of the poly(o‐hydroxy amide)s afforded polyethersulfone benzoxazoles. Most of the poly(o‐hydroxy amide)s were soluble in polar organic solvents such as N‐methyl‐2‐pyrrolidone; however, the polybenzoxazoles without the hexafluoroisopropylidene group were organic‐insoluble. The polybenzoxazoles exhibited glass‐transition temperatures (Tg) in the range of 219–282 °C by DSC and softening temperatures (Ts) of 242–320 °C by thermomechanical analysis. Thermogravimetric analyses indicated that most polybenzoxazoles were stable up to 450 °C in air or nitrogen. The 10% weight loss temperatures were recorded in the ranges of 474–593 °C in air and 478–643 °C in nitrogen. The methyl‐substituted polybenzoxazoles had higher Tg's but lower Ts's and initial decomposition temperatures compared with the corresponding unsubstituted polybenzoxazoles. For a comparative purpose, the synthesis and characterization of a series of sulfonyl polybenzoxazoles without the ether group that derived from 4,4′‐sulfonyldibenzoyl chloride and bis(o‐aminophenol)s were also reported. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2262–2270, 2001 相似文献