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91.
当前,大学生就业难问题已引起社会的广泛关注,来自农村的女大学生越来越成为就业边缘化的特殊群体。因此,了解农村女大学生就业现状,深入分析这一社会问题的成因,具有重要的理论意义和现实意义。 相似文献
92.
采用神话寓言的方式作为小说的结构,寄寓作者的某种创作意图,是中国传统小说的一个突出特征。《镜花缘》系清人李汝珍所著的一部颇有特色的长篇章回小说,不仅采用了神话寓言的方式作为小说的结构,而且,在这样的结构中,还十分醒目地贯穿了道教的谪仙托生母题。 相似文献
93.
The luminescence dating of the K-feldspar fraction is an alternative way for samples that cannot yield reasonable equivalent
dose (De) from quartz fraction with very weak luminescence signal. For testing the reliability of the infrared stimulated luminescence
(IRSL) dating of K-feldspar, luminescence dating was applied to quartz and K-feldspar fractions respectively for several Holocene
samples in this study. K-feldspar apparent ages using routine single aliquot regenerative-dose (SAR) protocol, K-feldspar
ages using g value correction method and ages from isochron dating method were compared with quartz ages. It is found that
the g value correction method cannot give reliable ages due to the large errors induced during measurements. The isochron
dating method is effective to the sample with problematically external dose rate. However, isochron dating may introduce a
relatively greater error during grain sizes — De curve fitting, therefore this method could obtain low-resolution ages for Holocene samples. Even K-feldspar apparent age
from routine SAR protocol is relatively younger by about 10% than the quartz age, it still could establish reasonable chronological
framework for Holocene samples. 相似文献
94.
"我作为一个青年学生对当时称作文化古城的北平,心向往之,终于在一个初冬的傍晚,乘火车到了前门车站。当我在暮色苍茫中随着拥挤的人群走出车站时,巍峨的正阳门和浑厚的城墙蓦然出现在我眼前。一瞬之间,我好像突然感到一种历史的真实。从这时起,一粒饱含生机的种子就埋在了我的心田中。在相继而来的岁月里,尽管风雨飘摇,甚至狂飙陡起,摧屋拔木,但是这粒微小的种子,却一直处于萌芽状态,把我引进历史的殿堂。"——侯仁之 相似文献
95.
96.
This article makes an attempt to investigate the low-frequency characterizations of pulse-type ground motions through ground motion components instead of original records. A decomposed method based on multi-resolution analysis is introduced in this article. The accuracy and validity of the method is tested in frequency domain, time domain and dynamic response. A dataset of 398 low-frequency components is obtained after the decomposition of 91 typical pulse-type records. A probabilistic model to describe the proportion of low-frequency components in corresponding original ground motions is established. At last, the decomposed method is used to investigate the impulsive characterizations of pulse-type ground motions. 相似文献
97.
20世纪30年代是近代中国大量译介国外各种唯物史观理论书籍的时期,一本多译的情况比较普遍。布哈林《历史唯物主义理论》一书便是其中中译本较多的著作。民国时期《历史唯物主义理论》多种译本的广泛流行,对传播历史唯物主义理论起到了积极作用。但是,时人注意到布哈林的理论中存在机械性等问题,故在将其作为知识资源时,逐渐扬弃之。深入考察《历史唯物主义理论》一书在20世纪30年代中国的译介、传播和理论扬弃,可以一窥民国时期国外同类理论著述影响中国思想界、学术界的复杂面相。研究唯物史观在近代中国的构建,不仅应梳理理论内在的演变逻辑,也须梳理其文本传播的演进脉络。在此基础上,对唯物史观理论中国化的具体历程,则会有更深入的认识。 相似文献
98.
99.
Jian Liu Chika Mouri Richard Laursen Feng Zhao Yang Zhou Wenying Li 《Journal of archaeological science》2013
In this paper we analyzed the natural dyes in well-preserved, ancient textiles from Yingpan, an important archaeological site on the Silk Road, using high-performance liquid chromatography with diode array and mass spectrometric detection. Dyes were removed from textile fibers using a soft extraction method (pyridine, water and oxalic acid). Two species of madder-type plants, Rubia tinctorum and Rubia cordifolia were identified as the dye sources in red and brown samples. We also were able to detect unusual flavonoid glycosides in yellow and green woolen yarns, although we have not been able to pinpoint with certainty a specific plant that may have been used to produce this dye(s). On the other hand, we found that yellow and green silk threads had been colored with protoberberine-type dyes, probably obtained from species of cork tree, Phellodendron spp., and/or other protoberberine producing plant. We propose that the textile dyes found at Yingpan reflect a merging of Eastern and Western practices and technologies during the 800-year period (206 BCE–618 CE) encompassing the early years of the Silk Road. 相似文献
100.