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31.
Dr. Cheng‐Chung Lee Dr. Manuel Maestre‐Reyna Dr. Kai‐Cheng Hsu Prof. Dr. Hao‐Ching Wang Prof. Dr. Chia‐I Liu Prof. Dr. Wen‐Yih Jeng Li‐Ling Lin Richard Wood Dr. Chia‐Cheng Chou Prof. Dr. Jinn‐Moon Yang Prof. Dr. Andrew H.‐J. Wang 《Angewandte Chemie (International ed. in English)》2014,53(48):13054-13058
Crown ethers are small, cyclic polyethers that have found wide‐spread use in phase‐transfer catalysis and, to a certain degree, in protein chemistry. Crown ethers readily bind metallic and organic cations, including positively charged amino acid side chains. We elucidated the crystal structures of several protein‐crown ether co‐crystals grown in the presence of 18‐crown‐6. We then employed biophysical methods and molecular dynamics simulations to compare these complexes with the corresponding apoproteins and with similar complexes with ring‐shaped low‐molecular‐weight polyethylene glycols. Our studies show that crown ethers can modify protein surface behavior dramatically by stabilizing either intra‐ or intermolecular interactions. Consequently, we propose that crown ethers can be used to modulate a wide variety of protein surface behaviors, such as oligomerization, domain–domain interactions, stabilization in organic solvents, and crystallization. 相似文献
32.
Shie-Chang Jeng 《Liquid crystals》2020,47(8):1223-1231
ABSTRACT The Tamm-plasmon-polariton (TPP) occurs at the interface between a metallic film and the photonic-crystal (PC) substrate. Unlike conventional surface-plasmon-polariton (SPP), TPP can be directly excited by both the transverse electric (TE) and transverse magnetic (TM) electromagnetic waves without using additional coupling optics. The fact that the optical functionality of most plasmonics devices is determined after fabrication limits their applications. Tunable SPP devices by applying liquid crystals (LCs) have been widely demonstrated due to their large birefringence and easy controllability via external stimuli. However, actively tuning TPP is difficult because the localised electric field is between the metallic film and PC substrate, the change of refractive index above the metallic film has only small influences on TPP. This article is intended to briefly review recent progress towards using LCs for actively tuning TPP devices. Not only TPP devices can gain benefits from LCs, we will also discuss the applications of TPP for measuring the anisotropy of the alignment films of LC devices. The sensitivity of the proposed scheme will be discussed. 相似文献
33.
34.
Hao-Ming Jeng Chung-Zen Tsai Tsu-Yen Chang 《Fresenius' Journal of Analytical Chemistry》1990,338(8):902-904
Summary The composition and stability of copper(I) complexes with thioacetamide (TAA) have been evaluated with the help of square-wave voltammetry using the fast pulse technique. Two species, namely Cu(I) (TAA) and Cu(I) (TAA)2, have been identified having the formation constants log 1=16.85; log 2=18.03. The complex is stable in highly acidic medium (pH1). The application for the determination of copper is pointed out. 相似文献
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36.
This paper discusses the structure of adsorbed water at interfaces. It begins with a review of the development of the research, then examines and compares some of the most important models in this field. The results of recent spectroscopic work, especially those of IR spectroscopy, are discussed and applied to the selection of the most probable model. 相似文献
37.
Kuo‐Chung Cheng Jiun‐Jeng Chen Wen‐Yen Chiu Lee Yih Wang Ping‐Chieh Wang 《Journal of polymer science. Part A, Polymer chemistry》2005,43(1):42-49
Dodecylbenzenesulfonic acid, DDBSA, was chosen as a new rate‐accelerating additive for 2,2,6,6,‐teramethyl‐1‐piperidinyloxy (TEMPO)‐mediated stable free radical polymerization of n‐butyl acrylate (n‐BA) monomers with 2,2′‐azobisisobutyronitrile (AIBN). It was found that the number‐average molecular weight of polymers could reach about ten thousand with a narrow polydispersity index (PDI) of 1.4 in a few minutes, which was faster than other systems reported previously. But, at higher conversion, the molecular weight distribution of polymers became broad, and a bimodal distribution occurred. The macro‐initiators isolated from the former polymers with narrow PDI could be extended by polymerization with monomers by the addition of DDBSA. Furthermore, a proposed kinetic model demonstrated that the decay of the concentration of DDBSA would reduce the living polymer concentration and retard the growth of the polymers, which could be further propagated by the supplement of DDBSA. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 42–49, 2005 相似文献
38.
Jen-Huang Jeng Hsieh T.E. 《Components and Packaging Technologies, IEEE Transactions on》2001,24(2):271-278
This work demonstrates the probing, testability and applicability of Al/PI (aluminum/polyimide) composite bumps to the chip on-glass (COG) bonding process for liquid crystal display (LCD) driver chip packaging. The experimental results showed that the thickness of Al overlayer on PI core of the bump, the location of pin contact, and the bump configuration affect bump probing testability. The bump with type IV configuration prepared in this work exhibited excellent probing testability when its Al overlayer thickness exceeded 0.8 μm. We further employed Taguchi method to identify the optimum COG bonding parameters for the Al/PI composite bump. The four bonding parameters, bonding temperature, bonding time, bonding pressure and thickness of Al overlayer are identified as 180° C, 10 s, 800 kgf/cm2 and 1.4 μm, respectively. The optimum bonding condition was applied to subsequent COG bonding experiments on glass substrates containing Al pads or indium tin oxide (ITO) pads. From the results of resistance measurement along with a series of reliability tests, Al pad is found to be a good substrate bonding pad for Al/PI bump to COG process. Excellent contact quality was observed when the bumps had Al overlayer thickness over 1.1 μm. As to the COG specimens with substrate containing ITO pads, high joint resistance suggested that further contact quality refinement is necessary to realize their application to COG process 相似文献
39.
Zhen-Cheng Wu Chiu-Chih Chiang Wei-Hao Wu Mao-Chieh Chen Shwang-Ming Jeng Lain-Jong Li Syun-Ming Jang Chen-Hua Yu Mong-Song Liang 《Electron Device Letters, IEEE》2001,22(6):263-265
This letter investigates the leakage mechanism in the Cu damascene structure with methylsilane-doped low-k CVD organosilicate glass (OSG) as the intermetal dielectric (IMD). The leakage between Cu lines was found to be dominated by the Frenkel-Poole (F-P) emission in OSG for the structure using a 50-nm SiC etching stop layer (ESL). In the structure using a 50-nm SiN ESL, the leakage component through SiN also made a considerable contribution to the total leakage in addition to the bulk leakage from trapped electrons in OSG. An appropriate ESL of sufficient thickness is essential to reduce the leakage for application to a Cu damascene integration scheme 相似文献
40.
Szu-Yu Wang Chih-Yuan Chin Pei-Ren Jeng Ling-Wu Yang Ming-Shiang Chen Chi-Tung Huang Jeng Gong Kuang-Chao Chen Ku J. Chih-Yuan Lu 《Electron Device Letters, IEEE》2005,26(6):363-365
Increasing attention has been paid to the peripheral gate-oxide integrity degradation of Flash memory devices that is induced by the tunnel-oxide nitridation. In this letter, the mechanisms of tunnel-oxide nitridation-induced degradation are characterized. We report that both a local oxide thinning effect and nitrogen residue will impact the integrity of gate-oxide. Minimizing the local thinning effect with an in situ steam generation (ISSG) oxidation process and removing the nitrogen residues from the silicon wafer surface by either an additional sacrificial oxide process or over-dip are proven to be useful in recovering the gate-oxide integrity. An optimum approach with the tunnel-oxide nitridation is proposed in this work that results in comparable or even better gate-oxide property than other approaches that have no tunnel-oxide nitridation process. 相似文献