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941.
Sabrina T. Howell 《Research Policy》2018,47(8):1448-1462
To spur technology transfer, emerging market policymakers often require foreign firms to form joint ventures (JVs) with domestic firms. Through knowledge spillovers, JVs may reduce technology acquisition costs for domestic firms. Yet domestic firm rents from JVs could discourage innovation through a cannibalization effect. Which force dominates is an empirical question. I address it with novel data on China's auto sector. In response to fuel economy standards requiring firms to upgrade technology or sacrifice quality, firms with JVs reduced quality and price relative to their counterparts. Consistent with cannibalization, firms with JVs drive the negative effect. 相似文献
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945.
E. A. Rowe 《Culture, Theory & Critique》2013,54(1):108-119
946.
Pirjo Aunio Jarkko Hautamäki Nina Sajaniemi Johannes E. H. Van Luit 《British Educational Research Journal》2009,35(1):25-46
The aim of this study was to explore the early numeracy of low‐performing young children. The mean age of the children was six years and four months. The 511 participants belonged to three groups: multi‐language children, children with special educational needs and children with average performance. The results showed that there were significant group differences in early numeracy: the children in the reference group had better relational and counting skills than those with a multi‐language background and those with special educational needs. Some differences were found in counting skills between the children with multi‐language background and those with special educational needs. Finally, (special) educational support for low‐performing children is discussed. 相似文献
947.
Laura E. Hume Christopher J. Lonigan Jessica D. McQueen 《Journal of Research in Reading》2015,38(2):172-193
This study examined how children's literacy interests related to parent literacy‐promoting practices across time. Using a sample of 909 preschool‐age children and the newly developed Child Activities Preference Checklist, literacy interest appeared to be a complex construct, not easily captured by a single measure. In a subsample of 230 children with longitudinal data, parent literacy practices and child literacy interests related concurrently and across time. Parent literacy practices were more stable than child literacy interests, with children's literacy interest continuing to develop over the preschool year. Parent practices of exposing children to literacy and teaching them literacy concepts appeared to be distinct constructs. Exposure to literacy was especially important in the growth of literacy interests and the hypothesis that exposure has a negative effect on children with little initial interest was not fully supported. 相似文献
948.
To date, a limited number of aqueous conditions have been tested experimentally as potential cleaning reagents on modern acrylic paint films. Those assessed have tended to extract measurable quantities of paint film components and distort the paint films physically. In this paper the results of a series of experiments designed to examine pH, conductivity, and specific ion effects of potential aqueous cleaning solutions on a series of commercial acrylic paints are reported. A three-dimensional microscopic technique was used to characterize the physical (volume and surface roughness) changes and liquid chromatography-tandem mass spectrometry was used to characterize the chemical (extracted surfactant) changes following paint film exposure to the aqueous solution. The tested paint films in this study clearly exhibit an isotonic point below which swelling and extraction is significant, and above which the swelling and extraction is diminished. Manipulation of conductivity and the ionic species in solution can reduce both the physical film changes and surfactant extraction from acrylic paint films; while pH appears to be of limited use in controlling aqueous cleaning effects. Moreover, there seems to be a specific ion effect for both swelling and de-swelling in acrylic paint films that can be rationalized through the Hofmeister Series. 相似文献
949.
N. M. Builova E. M. Epshtein V. G. Shamaev 《Scientific and Technical Information Processing》2008,35(1):28-29
The necessity for publishing a separate abstract journal on spintronics, which is a new, rapidly developing branch of physics, is substantiated. The interest in spintronics, which is the study of fundamental processes involving the simultaneous transport of both electron charge and electron spins in solids, as well as the interaction of electrons with a magnetic grating, is determined not only by its fascinating prospects but also the results that have already achieved. The spin and charge “degrees of freedom” open possibilities for the creation of semiconducting devices with parameters that are much superior to the existing ones and also the construction of devices that do not have analogues at present. First of all, this will permit problems of information transmission and processing to be solved in a new way. A detailed rubrication on spintronics is given in order to discuss the possibility of publishing a separate edition of an abstract journal devoted to spintronics. 相似文献
950.