冷光膜系的性能分析与技术改造     

戴国钧 《实验室研究与探索》2004,23(6):34-36

结合生产实际，介绍了冷光膜系的物理性能及特点，详细讨论分析了生产工艺中存在的问题，提出了改进的简便实用方法。采用改进的新方法能够提高冷光膜系制品的质量和工业化生产效率。  相似文献   

半导体光催化模拟光合磷酸化研究--单色(绿)光对ATP合成的影响     

常艳红  杨玲娟  雷新有  杨声  朱巧军  高翔 《天水师范学院学报》2003,23(2):30-32

以半导体材料（Zn·Cd）S：Ag-KI为催化剂，在单色(绿)光照下，成功地模拟了光合作用的光合磷酸化。在绿色光照下的光照度、照光时间、ADP(二磷酸腺苷) 浓度、Pi（磷酸氢二钠）浓度及催化剂量等对ATP（三磷酸腺苷）合成的影响。在合适的条件下，ADP 的浓度为1×10-1mmol/l 时的转化率可达到3.2%——5.8%。  相似文献   

从光的衍射看光的直线传播及像质问题     

张明霞 《天水师范学院学报》2001,21(5):15-17

光的衍射有近场衍射和远场衍射两种情形.近场衍射如小孔成像,当孔的尺寸比较大时,光线沿着直线传播,当孔小到一定程度,光线偏离了直线传播发生衍射,孔越小,衍射越显著,物体的几何像失去了清晰的轮廓,而且在边缘附近出现一系列明暗相间的条纹,从而影响了成像的质量;远场衍射如望远镜、显微镜,在物镜的像面上形成的几何像点由于衍射效应变成了一系列的衍射斑,衍射斑重叠越多,像越不清晰,严重影响了成像的质量,使得光学成像仪器的像分辨本领也有了限制.  相似文献   

一部汉语言文字学研究的力作--梁光华《汉语汉字论稿》读后   总被引：1，自引：1，他引：0  

王怀中  胡安顺 《黔南民族师范学院学报》2002,22(4):6-9

梁光华先生的《汉语汉字论稿》一书 ,收录了梁先生近年来的论文四十篇 ,内容涵盖了文字学、音韵学、训诂学、语法学、词汇学、方言学、文化语言学等诸多领域。本书有以下突出的优点 :1、注意发掘新问题 ,开拓新思路 ;2、占有丰富的材料 ;3、科学的研究方法 ;4、注意科研与教学的结合。洋洋洒洒三十余万言 ,均表现出梁先生深厚的语言学功底和敏锐的视角 ,是一部语言文字学研究的力作 ,一部值得语言学者尤其是青年学者一读的好书。需要商榷的一点是轻重唇音的分化时间问题 ,梁先生主张二者分化开始于唐末 ,完成于宋初《集韵》时代 (公元 1 1世纪初 )。而笔者则认为二者的分化应开始于南朝末年至唐代初年 (公元 6世纪末至 7世纪初 ) ,完成于唐代中期。  相似文献   

Consolidation of Black-dyed Māori Textile Artefacts: Evaluating the Efficacy of Sodium Alginate     

Catherine A. Smith  Rachel A. Paterson  Bronwyn J. Lowe  Rangi Te Kanawa 《文物保护研究》2018,63(3):139-154

Black-dyed artefacts are found in museums worldwide, many produced using an iron-tannate compound. Deterioration of iron-tannate dyed artefacts is an international preservation issue: in New Zealand the deterioration of paru (iron-tannate) dyed Māori textiles is widespread. This article reports experimental work testing the efficacy of sodium alginate, a consolidant developed for deteriorated paru-dyed muka (fibre from harakeke; Phormium tenax). The colour stability, strength retention, and acidity of paru-dyed muka consolidated with sodium alginate (0.25, 0.5, and 1% w/v in water) was tested pre- and post-artificial light ageing. This study found that sodium alginate had no negative effect on paru-dyed muka and in some cases provided benefit. Interestingly, the colour of paru-dyed muka is substantially more stable in UV-filtered light than previously recognised. Also microfading results were in agreement with visual assessments of colour change at 1 Mlux hour exposure, providing confidence in this relatively new technique to assess colour change.  相似文献   

Seeking Nettle Textiles – Utilizing a Combination of Microscopic Methods for Fibre Identification     

Jenni A. Suomela  Krista Vajanto  Riikka Räisänen 《文物保护研究》2018,63(7):412-422

Bast fibres have been commonly used as a textile material in Northern Europe since Neolithic times. However, the process of identifying the different species has been problematic, and many important questions related to their cultural history are still unanswered. For example, a modified Herzog test and the presence of calcium oxalate crystals have both been used in identification. In order to generate more reliable results, further research and advancement in multi-methodological methods is required. This paper introduces a combination of methods which can be used to identify and distinguish flax (Linum usitatissimum), hemp (Cannabis sativa), and stinging nettle (Urtica dioica). The research material consisted of reference fibres and 25 fibre samples obtained from 12 textiles assumed to be made of nettle. The textiles were from the Finno-Ugric and Historical Collections of The National Museum of Finland. The fibre samples were studied by observing the surface characteristics and cross sections with transmitted light microscopy, and by using a modified Herzog test with polarized light, in order to identify the distinguishable features in their morphological structures. The study showed that five out of 25 samples were cotton, 16 nettle, one flax, and one hemp. Findings from two samples were inconsistent. The results show that it is possible to distinguish common north European bast fibres from each other by using a combination of microscopic methods. Furthermore, by utilizing these combined methods, new and more reliable information could be obtained from historical ethnographic textiles, which creates new vistas for the interpretation of their cultural history.  相似文献   

Virtual Microscopy as a Learning Tool in Brazilian Medical Education     

Fernanda Somera dos Santos  Mariana Kiomy Osako  Gleici da Silva Castro Perdoná  Márcia Gaião Alves  Katiuchia Uzzun Sales 《Anatomical sciences education》2021,14(4):408-416

Virtual microscopy (VM) is a widely used teaching method in Medical Education in many developed countries. In Brazil, however, this is not the case for most medical schools, considering Brazilian social inequality and uneven access to technology. Recently, the Covid-19 pandemic has also challenged Universities to seek and make a transition toward more effective methods of full-time online education. Thus, the main goal of this work was to verify student's perception and academic performance, assessed upon VM implementation in a Brazilian Medical School. Ribeirao Preto Medical School students answered a 26-question survey with regards to optical microscopy (OM) and VM. Academic performance was compared between participants that were (year of 2019) or were not (year of 2015) exposed to VM. Taken the results together, subjective impressions such as handling, suitability, learning effectiveness, and pleasure using the tools, have shown a higher score for virtual microscopy (median = 29), when compared to optical microscopy (median = 24) with a P-value < 0.001 by Wilcoxon rank test, upon measurement using an ordinal scale. Regarding academic performance, no statistically significant differences were found between groups (P-value = 0.38, Cohen's d = 0.19). Therefore, VM proved to be adequate to the Brazilian medical education in light of Brazilian social contexts and Covid-19 pandemic.  相似文献   

发菜分布区生态特征分析   总被引：1，自引：0，他引：1  

黄健 《青岛职业技术学院学报》2005,18(1):62-64

根据文献资料和作者多年的研究,对发菜产地的自然环境,例如风、湿度、光线、温度和土壤等地貌特征,进行了综述。分析比较了藻体在休眠期和生长期中,各生态因素的主要不同点,并对微小生物环境对生长的影响做了剖析。最后,阐述了发菜的节律性生长与各生态因素的节律性变化的关系。  相似文献   

也谈《世说新语》何以不收陶渊明     

蒲日材 《天中学刊》2007,22(3):55-57,62

《世说新语》何以不收陶渊明?宁稼雨教授认为主要是陶氏家族在东晋没有取得世家大族的地位和声望所致。王建国博士商榷说一是与《世说新语》的收录旨趣有关,二是陶渊明那时的地位和影响远非我们现在所想象的那么重要。细较二人研究成果,究其原因主要是陶渊明不是清谈之士,其次还有家世衰微破落、文风平淡等,在当时没有产生广泛的影响和足够的声誉所致。  相似文献   

小孔成像在中国古代之研究     

陈绍金 《陕西理工学院学报(社会科学版)》1996,(6)

通过对古代有关小孔成像的观察和实验记载的分析，阐明了中国古代学者在光学发展的初期所作的贡献，同时也指出由于轻理论而重现象的定性描述使得在光学上的成就远落后于西方的历史教训。  相似文献