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82.
Innovation strategy and performance during economic transition: Evidences in Beijing, China 总被引:1,自引:0,他引:1
This paper evaluates the relevance of innovation strategy to various categories of Chinese firms and investigates its relationship with innovation performance during the economic transition of the 1990s. Data from 1244 Chinese firms in Beijing are used to ascertain the relative importance of different innovation objectives, along with the innovation strategies adopted by manufacturing firms. Results show that innovation activities were confined to the domestic sphere and mainly directed at quality improvement. Chinese manufacturing firms which obtained support from the government through the high-tech firm accreditation system generally perform better. They had already started moving away from a reliance on imported technology and equipment, and using indigenous R&D efforts to innovate for the coming market economy. 相似文献
83.
José Albors-Garrigós Jose Luis Hervas-OliverAuthor VitaePatricia MárquezAuthor Vitae 《International Journal of Information Management》2009
For traditional industries it is a real challenge, not only to achieve a clear product differentiation, but also to provide adequate services in order to ensure value and customer fidelity. 相似文献
84.
R. P. Clark Einar Lilja Eve Malmqvist Louis Arnaud Reid Edmund King John Downing C. M. Fleming Arnould Clausse G. de Landsheere Vernon Mallinson Paul Nash Tomio Goto M. A. Brimer Rudolf Cohen Gerhard Pause M. J. Langeveld W. E. Vliegenthart Emile Planchard 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1963,9(3):351-382
85.
86.
Paul F. Marty Author Vitae 《Library & information science research》2011,33(3):211-219
The recent development of personal digital collections systems on museum websites has prompted researchers to examine the motivations and expectations of museum visitors as they interact with those systems. Results from an online survey completed by visitors to six different museum websites show that users of personal digital collections systems are primarily motivated by a desire to create simple collections of objects and images, and are less influenced by the more complicated features museums have implemented to encourage user participation. The significance of these findings is explored through a discussion of user expectations and motivations with respect to creating personal digital collections, and an attempt is made to reconcile some of the disparities between the perceptions of survey respondents and the experiences of museum professionals developing and implementing personal digital collections systems. 相似文献
87.
Skedsmo Guri Huber Stephan Gerhard 《Educational Assessment, Evaluation and Accountability》2019,31(2):151-153
Educational Assessment, Evaluation and Accountability - 相似文献
88.
ABSTRACTChalconatronite, Na2[Cu(CO3)]2·3H2O, is formed as a corrosion product when copper alloys are exposed to sodium carbonate solutions in the air. This also happens when metals come into contact with corroding soda glass which forms alkaline surface films in reaction with humidity from clean air. More often, substantial amounts of formaldehyde are present indoors which react to formate via the Cannizzarro reaction and accumulate over time in the films. Twenty cases of chalconatronite (including two mentioned in the literature) are reported as occurring on heritage objects with glass in contact with copper alloys: Baroque reliquaries with set glass gems, enamel on metal (sixteenth century and a modern replica of intentionally unstable composition), Christmas tree glass baubles with wires, glass buttons with metal shanks, a glass figure with a wire support, miners’ lamps, and a glass framed daguerreotype. These confirmed identifications might help conservators in investigating similar cases to shed more light on the formation conditions. 相似文献
89.
A sodium copper formate, first described in 2002, can also form on copper alloys with sodium originating from soda glass hydrolysis. The frequent occurrence (50% of 250 cases of glass-induced metal corrosion) is due to the presence of formaldehyde emissions in storage and its direct reaction to formate in the alkaline surface films. The compound can be produced without the presence of acetate when chalconatronite or metal coupons immersed in soda solution are exposed to formaldehyde vapours. The crystal structure, derived from X-ray powder diffraction, yielded the sum formula Cu4Na4O(HCOO)8(OH)2·4H2O. Except for the absence of acetate in the structure, this is in good agreement with the 2002 publication. To assess which kind of combined glass/metal objects are affected, a number of large museum collections were surveyed. Sodium copper formate was detected as a corrosion product using mainly micro-Raman spectroscopy, for instance, on 18 painted Limoges enamels, eight glass vessels with metal mountings, glass beads on metal wire from 11 bridal crowns, nine Christmas tree balls with wire decoration, 40 pieces of jewellery with glass gems, three daguerreotypes, and one miniature with cover glasses. 相似文献
90.
Copper(II) hydroxide (as the rarely occurring mineral spertiniite) is formed under alkaline, oxidising conditions. It has been observed as a naturally occurring corrosion product of brass in sea water. But most occurrences on copper alloys are due to conservation treatments using basic solutions (sodium hydroxide or ammonia) or to intentional patination. Classical brass centrepieces (c. 1800), ‘cleaned’ with ammonia solution, developed a blue spertiniite patina in gaps, where evaporation was hindered. Additional to the danger of stress corrosion cracking this is another reason now outlawing this treatment. Copper pigment layers will transform to copper hydroxide when exposed to bases. The treatment of basic copper salts with bases has been used intentionally in the production of Bremen blue and similar pigments which can be composed of copper hydroxide as well. 相似文献