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21.
新型保温材料—炭化稻壳在连铸生产中的应用效果 总被引:3,自引:0,他引:3
对新型保温材料──炭化稻壳的理化指标及其保温性能进行了阐述。在连铸生产中采用炭化稻壳做保温剂可取得显著的经济效益,是理想的保温材料。 相似文献
22.
The compressive stress-strain relationships of two puffed cereals, rice and corn based, in bulk were determined using a Universal Testing Machine. The general sigmoid shape of the relationship could be described by a four parameter empirical model originally developed for cellular solids. Jaggedness could be expressed in terms of an apparent fractal dimension and/or the mean magnitude of the power spectrum determined using the Fast Fourier Transform. Both measures as well as a particular parameter of the empirical model were sensitive indicators of the changes in the stress-strain relationships resulting from exposure to different relative humidities. Although the stress strain relationship, especially of dry samples, had an irregular, irreprodu-cible shape, the magnitude of the two roughness measures was highly reproducible. 相似文献
23.
岑雪苇 《浙江工业大学学报》2007,(1)
禅宗解脱的实质是生命的自由。通过明心见性、转迷入悟的途径,心灵摆脱烦恼业障,进入无我境界,从而体验到一种想象的自由。这一过程在很多方面类似审美活动,在体验上具有审美自由的特征。但禅宗的解脱,以及解脱所达到的审美的人生境界之可能,其关键在于生命主体的自我消解。无我的或曰没有主体的自由,并不是一种真正的自由。因而,禅宗关于人的解放的理论和实践,其价值仅仅在宗教方面和美学方面。 相似文献
24.
Algorithms for automatic playlist generation solve the problem of tedious and time consuming manual selection of musical playlists. These algorithms generate playlists according to the user’s music preferences of the moment. The user describes his preferences either by manually inputting a couple of example songs, or by defining constraints for the choice of music. The approaches to automatic playlist generation up to now were based on examining the metadata attached to the music pieces. Some of them took also the listening history into account. But anyway, a heavy accent has been put on the metadata, while the listening history, if it was used at all, had a minor role. Missings and errors in metadata frequently appear, especially when the music is acquired from the Internet. When the metadata is missing or wrong, the approaches proposed so far cannot work. Besides, entering constraints for the playlist generation can be a difficult activity. In our approach we ignored the metadata and focused on examining the listening habits. We developed two simple algorithms that track the listening habits and form a listener model—a profile of listening habits. The listener model is then used for automatic playlist generation. We developed a simple media player which tracks the listening habits and generates playlists according to the listener model. We tried the solution with a group of users. The experiment was not a successful one, but it threw some new light on the relationship between the listening habits and playlist generation. 相似文献
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26.
To examine the separate effects of viscosity and sweetness on astringency, aqueous solutions of grape seed tannin (GST) were thickened with carboxymethyl cellulose (CMC) from 2 to 45 cP (experiment 1) or sweetened with 0 to 1.8 g/L aspartame (experiment 2). Trained subjects continuously rated astringency and bitterness in duplicate. Subjects were categorized by the salivary flow induced by citric acid and ability to taste n-propyl thiouracil (PROP). In experiment 1, maximum intensity and total duration of astringency were significantly decreased as viscosity rose, although time to maximum intensity of astringency was not affected. Maximum intensity and total duration of bitterness were not significantly affected by increasing viscosity; however, the onset of bitterness was significantly delayed. In experiment 2, increasing sweetness had no affect on any astringency parameter, although maximum intensity of bitterness was significantly decreased. Neither PROP nor salivary flow-status had any effect on perception of bitterness or astringency in either experiment. 相似文献
27.
本文介绍了我国水稻害虫发生的种类,主要稻虫的种群消长,对水稻危害的损失,在各个不同年代,通过研究和防治,总结出对抗虫品种评价与利用的研究发展迅速,新农药的试验开发效果明显。70年代以来,按我国稻区生态条件和稻虫为害的特点,形成了江淮、太湖平原、川西平原、洞庭湖平原和珠江三角洲五大稻区的水稻病虫综合防治技术体系,主要技术路线是以农业防治为基础,抗性品种为主体,依靠经济防治指标,协调农药防治和利用天敌 相似文献
28.
通过垄畦栽冷渍型稻田早、中稻化肥不同施量及施用方法的田间试验,建立氮、磷、钾化肥施用量与产量的回归方程,推导出早、中稻氮、磷、钾化肥最佳施用量;在施肥量相等情况下,深施比表施肥效好,钾肥不足情况下,以稻草代钾肥同样取得较好增产效果。 相似文献
29.
依据非充分灌溉原理,水稻在适度的水分亏缺的情况下,具有一定的适应和抵抗效应,本项研究利用这一特点,对水稻分蘖阶段进行不同灌水量的试验,探求水稻分蘖期的适宜灌水量及其需水规律。 相似文献
30.