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71.
Yi‐Chun Kung Sheng‐Huei Hsiao 《Journal of polymer science. Part A, Polymer chemistry》2011,49(22):4830-4840
Two new aromatic poly(amide‐hydrazide)s (PAHs)‐bearing electroactive pyrenylamine units in the backbone were prepared from the phosphorylation polycondensation reactions of N,N‐di(4‐carboxyphenyl)‐1‐aminopyrene ( 1 ) with p‐aminobenzoyl hydrazide (p‐ABH) and m‐aminobenzoyl hydrazide (m‐ABH), respectively. The PAHs could be further cyclodehydrated into the corresponding poly(amide‐1,3,4‐oxadiazole)s in the range of 300–400 °C in the solid film state. All the hydrazide and oxadiazole polymers were soluble in many polar organic solvents and could afford flexible and strong films via solution casting. The poly(amide‐1,3,4‐oxdiazole)s had high glass‐transition temperatures (294–309 °C) and high thermal stability (10% weight‐loss temperature in excess of 520 °C). The dilute solutions of all the hydrazide and oxadiazole polymers showed strong fluorescence with emission maxima around 457–459 nm in the blue region. Copolymers obtained from the polycondensation of equimolar mixture of diacid 1 and 4,4′‐oxydibenzoic acid with p‐ABH or m‐ABH exhibited a significantly increased fluorescence quantum efficiency in comparison with the homopolymers. Cyclic voltammetry results indicated that all the hydrazide and oxadiazole polymers exhibited an ambipolar (n‐ and p‐doping processes) and electrochromic behavior. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011. 相似文献
72.
Highly Fluorescent Thienoviologen‐Based Polymer Gels for Single Layer Electrofluorochromic Devices
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Amerigo Beneduci Sante Cospito Massimo La Deda Giuseppe Chidichimo 《Advanced functional materials》2015,25(8):1240-1247
A highly fluorescent electrofluorochromic gel with quantum yields as high as 67% is prepared by incorporating the thienoviologen fluorophore 4,4′‐(2,2′‐bithiophene‐5,5′‐diyl)bis(1‐nonylpridinium)bistriflimide into a polymeric matrix. The fluorescent emission spectrum of the gel at low percentages of thienoviologen shows a strong band at 530 nm. A new intense fluorescence band at 630 nm can be induced by fluorophore aggregation. Single layer electrofluorochromic devices were readily prepared by sandwiching the polymer gels between two indium tin oxide (ITO) electrodes. The fluorescence intensity can be easily modulated between a fluorescent and a quenched state, in a wide visible spectral range, by direct electrochemical reduction of the thienoviologen fluorophore. It exhibits three reduction states, each with different emission properties. The reversible interconversion among these states leads to a high electrofluorochromic stability of the device, exhibiting switching times of a few seconds and, to the best of our knowledge, the highest contrast ratio (337). 相似文献
73.
Serife O. Hacioglu Emre Ataoglu Gonul Hizalan Tolga Depci Levent Toppare 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):937-946
AbstractTwo novel thiadiazoloquinoxaline and benzodithiophene (BDT) bearing copolymers were designed and synthesized. Different BDT units (alkoxy and thiophene substituted) were used as donor materials and the effect of alkoxy and thiophene substitution on the electrochemical, spectroelectrochemical and photovoltaic properties were investigated. Both polymers exhibited low oxidation potentials at around 0.90 V and low optical band gaps at around 1.00?eV due to the insertion of electron poor thiadiazoloquinoxaline unit into the polymer backbone. Both P1 (poly-6,7-bis(3,4-bis(decyloxy)phenyl)-4-(4,8-bis(nonan-3-yloxy)benzo[1,2-b:4,5-b']dithiophen-2-yl)-[1, 2, 5]thiadiazolo[3,4-g]quinoxaline) and P2 (poly- 4-(4,8-bis(5-(nonan-3-yl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophen-2-yl)-6,7-bis(3,4-bis(decyloxy)phenyl)-[1, 2, 5]thiadiazolo[3,4-g]quinoxaline) exhibited multichromic behavior with different tones of greenish yellow and gray in the neutral and fully oxidized states, respectively. In addition, both polymers revealed very high optical contrasts (~87%) in the NIR region which make these promising polymers good candidates for NIR applications. Finally, in order to explore the organic photovoltaic performances, P1 and P2 were mixed with PC71BM in the active layer of organic solar cells (OSCs) by conventional device structure. As a result P1 and P2 based devices revealed power conversion efficiencies (PCEs) of 0.33% and 0.60% respectively. However, the additive treatment enhanced PCE from 0.49 to 0.73% for P2 based devices. 相似文献
74.
Juan‐Ramn Jimnez Jana Glatz Amina Benchohra Geoffrey Gontard Lise‐Marie Chamoreau Jean‐Franois Meunier Azzedine Bousseksou Rodrigue Lescouëzec 《Angewandte Chemie (International ed. in English)》2020,59(21):8089-8093
A mixed‐valence {MnII3MnIIIFeII2FeIII2} cyanide‐bridged molecular cube hosting a caesium cation, Cs?{Mn4Fe4}, was synthesized and structurally characterized by X‐ray diffraction. Cyclic‐voltammetry measurements show that its electronic state can be switched between five different redox states, which results in a remarkable electrochromic effect. Magnetic measurements on fresh samples point to the occurrence of a spin‐state change near room temperature, which could be ascribed to a metal‐to‐metal electron transfer converting the {FeII?CN?MnIII} pair into a {FeIII?CN?MnII} pair. This feature was only previously observed in the polymeric MnFe Prussian‐blue analogues (PBAs). Moreover, this novel switchable molecule proved to be soluble and stable in organic solvents, paving the way for its integration into advanced materials. 相似文献
75.
Large‐Scale Fabrication of Pseudocapacitive Glass Windows that Combine Electrochromism and Energy Storage
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Peihua Yang Peng Sun Zhisheng Chai Prof. Langhuan Huang Dr. Xiang Cai Prof. Shaozao Tan Prof. Jinhui Song Prof. Wenjie Mai 《Angewandte Chemie (International ed. in English)》2014,53(44):11935-11939
Multifunctional glass windows that combine energy storage and electrochromism have been obtained by facile thermal evaporation and electrodeposition methods. For example, WO3 films that had been deposited on fluorine‐doped tin oxide (FTO) glass exhibited a high specific capacitance of 639.8 F g?1. Their color changed from transparent to deep blue with an abrupt decrease in optical transmittance from 91.3 % to 15.1 % at a wavelength of 633 nm when a voltage of ?0.6 V (vs. Ag/AgCl) was applied, demonstrating its excellent energy‐storage and electrochromism properties. As a second example, a polyaniline‐based pseudocapacitive glass was also developed, and its color can change from green to blue. A large‐scale pseudocapacitive WO3‐based glass window (15×15 cm2) was fabricated as a prototype. Such smart pseudocapacitive glass windows show great potential in functioning as electrochromic windows and concurrently powering electronic devices, such as mobile phones or laptops. 相似文献
76.
Dimeric Tetrathiafulvalene Linked to pseudo‐ortho‐[2.2]Paracyclophane: Chiral Electrochromic Properties and Use as a Chiral Dopant
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Kosuke Kobayakawa Dr. Masashi Hasegawa Hiroaki Sasaki Junta Endo Dr. Hideyo Matsuzawa Dr. Katsuya Sako Dr. Jun Yoshida Dr. Yasuhiro Mazaki 《化学:亚洲杂志》2014,9(10):2751-2754
A dimeric tetrathiafulvalene installed into a chiral pseudo‐ortho‐[2.2]paracyclophane framework was synthesized as a novel chiral electrochromic material. This compound exhibited pronounced chiroptical properties in the UV‐Vis‐NIR range depending on its redox states without racemization. Each enantiomer was examined as a chiral dopant for nematic liquid crystals (LCs), and the induced helicity of the LC solvent was in accord with that of the tetrathiafulvalene compound. 相似文献
77.
Hiromori Tsutsumi Yoko Nakagawa Koii Miyazaki Masayuki Morita Yoshiharu Matsuda 《Journal of polymer science. Part A, Polymer chemistry》1992,30(8):1725-1729
Polymer gel films [poly(1-vinyl-2-pyrrolidinone-co-N,N′-methylenebisacrylamide) (PVPD)] which contain simple organic electrochromics [p-diacetylbenzene (p-DAB), dimethyl- or diethyl terephthalate (p-DMP or p-DEP)] are prepared and their optical responses to applied voltage are investigated. p-DAP/PVPD film is colored in green by the application of 1.2 V vs. Pt wire (quasireference electrode) across the film, and p-DMP/PVPD and p-DEP/PVPD films are colored in red by the application of ?2.5 and ?1.5 V vs. Pt, respectively. Their coloring responses are about a few seconds and the bleaching process also occurs rapidly. The films have no optical memory effect. © 1992 John Wiley & Sons, Inc. 相似文献
78.
电沉积三氧化钨薄膜电致变色及其光电化学性能 总被引:9,自引:0,他引:9
电沉积WO3薄膜显示出可逆光致变色及电致变色行为(在红外区域附近具有蓝色光吸收)。通过X射线光电子能谱(XPS),对WO3薄膜在不同呈色水平上的W4f核能级作了观察研究,可见W4f核能级在WO3膜显色后变宽,光电化学测定表明WO3薄膜具有低光电转换效率。 相似文献
79.
Gingras M Placide V Raimundo JM Bergamini G Ceroni P Balzani V 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(33):10357-10363
We have synthesized a novel class of dendrimers, consisting of a polysulfurated pyrene core with appended poly(thiophenylene) dendrons (PyG0, PyG1, and PyG2, see Scheme 1), which exhibit remarkable photophysical and redox properties. In dichloromethane or cyclohexane solution they show a strong, dendron-localized absorption band with a maximum at around 260 nm and a band in the visible region with a maximum at 435 nm, which can be assigned to the pyrene core strongly perturbed by the four sulfur substituents. The dendrimers exhibit a strong (Phi=0.6), short-lived (tau=2.5 ns) core-localized fluorescence band with maximum at approximately 460 nm in cyclohexane solution at 293 K. A strong fluorescence is also observed in dichloromethane solution at 293 K, in dichloromethane/chloroform rigid matrix at 77 K, and in the solid state (powder) at room temperature. The dendrimers undergo reversible chemical and electrochemical one-electron oxidation with formation of a strongly colored deep blue radical cation. A second, reversible one-electron oxidation is observed at more positive potential values. The photophysical and redox properties of the three dendrimers are finely tuned by the length of their branches. The strong blue fluorescence and the yellow to deep blue color change upon reversible one-electron oxidation can be exploited for optoelectronic devices. 相似文献
80.