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1.
Reading Motivation: Multidimensional and Indeterminate. 总被引:1,自引:0,他引:1
The Motivations for Reading Questionnaire (MRQ) contains 54 items that are posited to tap 11 dimensions of reading motivation. The structural validity of the MRQ was investigated with 2 samples: (a) 328 students in Grades 3-5 from 2 suburban mid-Atlantic elementary schools and (b) 735 students in Grades 3-5 in 2 suburban southwestern elementary schools. With confirmatory factor analyses (CFAs), the theoretical 11-factor structure did not adequately fit the data in either sample. Subsequently, exploratory factor analyses found 8 factors for each sample with 6 factors defined by only 3 or 4 common items. However, a double CFA cross-validation found an inadequate fit for both samples. Given these results, the authors suggest that the MRQ be revised. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
本文阐述了麻醉剂(氨氟醚或异氟醚)与二氧化碳浓度监测系统的微机控制与信息处理子系统.该子系统完成传感器输出电信号与气体分压强的转换、误差的自动校正、非正常情况的报警、吸入与呼出麻醉剂分压及二氧化碳呼气末分压的自动搜索、呼吸频率的检测等任务,使整个监测系统的功能扩展,性能明显提高. 相似文献
3.
Poly(vinyl alcohol) is crosslinked in dilute solution (c=0.1 wt%) with glutaraldehyde. The reaction product is characterized by viscometry and gel permeation chromatography (g.p.c.). The intrinsic viscosity decreases with increasing degree of crosslinking and does not depend on temperature. G.p.c. reveals that the reaction product is not homogeneous, but consists of a mixture of particles with different sizes, possibly both intra- and intermolecularly crosslinked molecules. The intramolecularly crosslinked molecules are smaller in size than the initial polymer molecules and their size depends on the degree of crosslinking. They possess a narrow particle size distribution even if the initial polymer sample had a broad molecular weight distribution. 相似文献
4.
用己二酸二酰肼(ADH)对透明质酸(HA)进行化学修饰,制备交联透明质酸(HA-ADH)薄膜。粘度法测试表明HA-ADH是一种可降解的生物材料,并且与HA相比,HA.ADH的降解速率减慢。在此基础上,研究了以疏水性的替硝唑(TDZ)和亲水性的头孢唑啉钠(CEZ)为模拟药物的HA-ADH药物载体薄膜的释药性能。紫外-可见(UV-Vis)吸收光谱检测表明,HA-ADH是一种疏水性药物TDZ的优良缓释制荆,这是由于TDZ的疏水性和HA-ADH薄膜的缓慢溶胀和降解性能的结合而得到的,药物的释放主要受扩散机制控制。 相似文献
5.
6.
压电超声微电机是依靠定子振动变换能的功率器件,定子性能将直接关系到微电机能否实现,本文采用Rayleigh-Ritz方法来分析机械中经常采用的多层膜结构(混合结构)定子的固有振动特性,推导中考虑了平面应力和弯曲应力对固有频率的影响,模拟计算和实验结果符合得较好,此外还讨论了定子有关参数对固有频率的影响。 相似文献
7.
Sexual incentive motivation was evaluated in a procedure consisting of a large open field where incentive animals were confined behind wire mesh openings. When sexually inexperienced male rats (Rattus norvegicus) were exposed to the receptive female-male incentives, they spent more time close to the female. If the incentives were receptive female-nonreceptive female, the receptive female was preferred. However, when the alternatives were nonreceptive female-male, no preference was obtained. Castration abolished preference for the receptive female, and treatment with testosterone propionate restored it. Estradiol plus oil is as efficient as estradiol plus progesterone for giving the ovariectomized female incentive properties. The living female can be replaced with female odor. Sexual experience did not have any long-term effects on the female's incentive value, but immediately preceding limited sexual activity enhanced it. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
This study examines the links between antecedents and consequences of Gabonese teachers' (N= 152) work motivation. The theoretical underpinnings are based on the Motivational Model of Job Burnout (MMJB) which is grounded in Self-Determination Theory (SDT) and states that the more supervisors satisfy an employee's need for self-determination, competence, and relatedness, the more self-determined is the latter's work motivation. The level of self-determined motivation has an impact on job satisfaction, which in turn determines life satisfaction. Higher levels of self-determined motivation also buffer emotional exhaustion and psychological distress. The model was confirmed via structural equation modeling and provides support for the validity and generalizability of the MMJB and SDT. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
高温稀土永磁Sm2(Co,Cu,Fe,Zr)17 的制备和性能 总被引:5,自引:0,他引:5
制备了高温稀土永磁材料Sm(Coba1Fe0.26Cu0.05Zr0.026)7.0,研究了磁性能与工艺条件的关系.结果表明:提高烧结温度可使材料的Br和(BH)max增大,但是使Hci降低;适当提高真空预烧温度,可使材料在较低烧结温度下致密化,具有较高的Hci和(BH)max和温度稳定性.真空预烧温度过高使性能的急剧降低,其主要原因是Sm的析出.在最佳工艺条件下材料的磁性能参数分别为:Br1.08T3Hci2286kA/m,Hcb932kA/m,(BH)max220.8kJ/m^3;β20-200℃为-0.19%/℃. 相似文献
10.
Baschnagel Joseph S.; Hawk Larry W. Jr.; Colder Craig R.; Richards Jerry B. 《Canadian Metallurgical Quarterly》2007,121(6):1372
In humans, prepulse inhibition (PPI) of startle is greater during attended prestimuli than it is during ignored prestimuli, whereas in rats, most work has focused on passive PPI, which does not require attention. In the work described in this article, researchers developed a paradigm to assess attentional modification of PPI in rats using motivationally salient prepulses. Water-deprived rats were either conditioned to attend to a conditioned stimulus (CS; 1-s, 7-dB increase in white noise) paired with water (CS+ group), or they received uncorrelated presentations of white noise and water (CSo group). After 10 conditioning sessions, startle probes (50 ms, 115 dB) were introduced, with the CS serving as a continuous prepulse. Three experiments examined PPI across a range of prepulse intensities (4-10 dB) and stimulus onset asynchronies (SOAs; 30-960 ms). PPI was consistently reduced in the CS+ group, particularly with a 10-dB prepulse and a 60-ms SOA. Thus, PPI in rats differed between attended and ignored prestimuli, but the effect was reversed in the results of research with humans. A fourth study eliminated the group difference by reversing the CS-water contingency. Methodological and motivational hypotheses regarding the current findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献