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汽车驾驶员动态视觉特性试验研究

拖拉机与农用运输车 2010年第6期37卷 16-18,20页

作者：李永芳上海工程技术大学汽车学院上海201620

利用眼动仪系统纪录分析了在不同车速条件下车辆通过不同字高的交通标志牌时驾驶员眼睛注视点和注视时间的分布规律。结果表明车速和交通标志牌字体高度对驾驶员判读标志信息的过程产生较大影响:在接近标志牌的过程中,随着车速的增加,... 详细信息

利用眼动仪系统纪录分析了在不同车速条件下车辆通过不同字高的交通标志牌时驾驶员眼睛注视点和注视时间的分布规律。结果表明车速和交通标志牌字体高度对驾驶员判读标志信息的过程产生较大影响:在接近标志牌的过程中,随着车速的增加,驾驶员眼睛注视点的几何中心向标志牌偏移,注视范围变小,视线变的更加集中,注视时间也随着车速的增加而延长;在一定车速条件下,当字体较小的时候,驾驶员注视点较集中,判读标志信息的时间较长,随着字体变大,驾驶员注视点越分散,视认性越好,判读时间缩短。

关键词：汽车驾驶员动态视觉特性试验研究 Driver Car Study Test characters Visual 眼睛注视点交通标志牌车速注视时间标志信息字体判读条件时间缩短几何中心

Preparation and Characteristics of Wool Keratin Aqueous Solution and Sponge

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Journal of Donghua University(English Edition) 2012年第4期29卷 359-362页

作者：柯贵珍陈曦于伟东 Department of Textile Science and Engineering Wuhan Textile University College of Textiles Donghua University

Wool keratin has broad application prospects in biomedical materials, tissue engineering, and other fields. To obtain porous wool keratin membrane with good performance, and lay the foundation for its application in biological fields in the future, wool keratin aqueous solution and sponge were prepared and their characters were discussed. Wool fiber was dissolved with a mixture of urea, β-mercapitoethanol, sodium dodecyl sulfate(SDS) and water, and stable keratin aqueous solution was prepared through filtration and dialysis. Dissolution rate under different conditions was discussed. The results show that dissolution rate increases with the increase of dissolving temperature, reduction β-mercaptoethanol and assistant agent urea concentration and the addition of SDS. SDS polyacrylamide gel electrophoresis (SDS PAGE) shows the major molecular weight of the aqueous keratin solution is between 44300 u and 66400 u. Amino acid analysis shows the cysteine acid content of the keratin solution decreases obviously. Wool keratin sponge was made from the keratin solution with freeze drying method and its structure and characters were studied with scanning electron microscopy(SEM) and Fourier transform infrared spectrometer (FTIR). The results indicate that keratin sponge has evident pores structure, and the conformation of the sponge is β-sheet.

关键词： wool keratin solution keratin sponge characters

Characterization of Congolese Strains of <i>Xanthomonas axonopodis</i>pv. <i>manihotis</i>Associated with Cassava Bacterial Blight

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American Journal of Plant Sciences 2014年第9期5卷 1191-1201页

作者： G. Mamba-Mbayi P. Tshilenge-Djim K. K. Nkongolo A. Kalonji-Mbuyi Department of Biology Faculty of Sciences & Engineering Laurentian University Sudbury Canada Unit of Phytopathology Faculty of Agronomy University of Kinshasa Kinshasa DR-Congo

Cassava bacterial blight (CBB) caused by Xanthomonas axonopodis pv. manihotis has been reported in several African countries since 1970. Knowledge of the virulence and diversity of Xanthomonas axonopodis pv. manihotis strains is important for an integrated control of CBB. The main objective of the present study was to characterize strains of Xanthomonas axonopodis collected from various regions in the DR-Congo. There was variability among strains for shape (form), contour (margin) and elevation. Bacterial cell size for the strains analyzed varied from 24.1 μm × 11.3 μm to 11.4 μm × 4.2 μm. All the Xanthomonas axonopodis pv. manihotis strains but one was motile. Two distinctive groups were identified based on radial growth of their colonies. The first group grows faster (7.8-10.5 mm/d) compared to the second group (4.8-6.9 mm/d). Five strains (Gandajika, Inera/Stat, Kansasa, Mulumba and Musakatshi) were classified as virulent with a damage rating ≤ 1 and four were aggressive (Luputa, M'vuazi, Boketa and Kiyaka) with a damage rating > 1. Significant differences were also observed among strains for disease onset, incidence and plant mortality. The highest incidence (33%) of bacterial blight 21 days after infestation (DAI) resulted from the Boketa strain inoculation and the lowest (0 % disease incidence) from INERA/STAT and Musakatshi strains. There was no clear association between geographic origin of the strains and their aggressiveness.

关键词： Cassava Bacterial Blight (CBB) Xanthomonas axonopodis pv. manihotis Morphological and Physiological characters CBB Incidence Strains Aggressiveness DR-Congo

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蔬菜叶面喷肥

山西成人教育 1995年第7期 46-页

蔬菜叶面喷肥蔬菜叶面质肥的方式很好。喷施的肥料种类很多，应根据蔬菜的分类恰当适用。１．长叶蔬菜：大白菜、菠菜、芹菜、韭菜等凡是以食叶为主的蔬菜都叫叶菜。喷肥时应以氮素肥为主，氮素肥有碳铵、尿素、硫铵、磷酸铵等氮肥或氮... 详细信息

蔬菜叶面喷肥蔬菜叶面质肥的方式很好。喷施的肥料种类很多，应根据蔬菜的分类恰当适用。１．长叶蔬菜：大白菜、菠菜、芹菜、韭菜等凡是以食叶为主的蔬菜都叫叶菜。喷肥时应以氮素肥为主，氮素肥有碳铵、尿素、硫铵、磷酸铵等氮肥或氮与其它肥料的复合肥。肥液浓度：碳铵...

关键词： Legumine Genera Distrbution types characters of nodulation and nitrogen-fix- ation

POLYMER-SUPPORTED LEWIS ACID CATALYST:POLYSTYRENE-FERRIC CHLORIDE COMPLEX——ITS PREPARATION AND USE FOR ORGANIC SYNTHESIS

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Chinese Science Bulletin 1987年第6期32卷 388-394页

作者：冉瑞成裴伟伟贾欣茹沈吉蒋硕健 Department of Chemistry Peking University Department of Chemistry Peking University Department of ChemistryBeijing Chemical Fiber College Department of Chemistry Peking Universityhe composition and structure of polymers may be tailor-made to give them various functions and specific characters. Recently uses of functional polymers in chemical reactions have become increasingly widespread and are one of the important and rapidly developing fields of polymer science. Polymer catalysts are an important kind of functionalized polymers and have been receiving more and more attention. The polymer catalysts consisting of polystyrene with AlCl_3 and BF_3 have been made by Neckers and

The composition and structure of polymers may be tailor-made to give them various functions and specific characters. Recently, uses of functional polymers in chemical reactions have become increasingly widespread and are one of the important and rapidly developing fields of polymer science. Polymer catalysts are an important kind of functionalized polymers, and have been receiving more and more attention. The polymer catalysts consisting of polystyrene with AlCl3 and BF3 have been made by Neckers

关键词： polystyrene ACID tailor widespread characters benzene witht evident reused acetone

Refractory Minerals in Henan Province

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China's Refractories 2004年第1期13卷 22-27页

作者： JINQinguo LIJing LIUJiehua LIUYanjun HenanMineralsandRefractoriesCompany ZhengzhouChina LuoyangInstituteofRefractoriesResearch LuoyangHenan471039China

Henan province is very rich in refractory minerals of many varieties including silica, dolomite, graphite, pearlite, sepiolite, olivine, and sillimanite group minerals, besides the abundant reserves of fireclay and bauxite, which lay a good foundation for the development of the refractories industry of the province. The paper introduces the reserves, distribution and character of the refractory minerals in Henan province.

关键词： Refractory minerals Reserves Distribution characters Henan province

Numerical Analysis of Reinforcement Structure Stability Based on the Stress State of Geogrid

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World Journal of Engineering and Technology 2018年第2期6卷 383-392页

作者： Xiaosong Tang Yongfu Wang Zhixiang Liu China Merchants Chongqing Communications Technology Research & amp Design Institute Co. Ltd. Chongqing China Engineering and Technology Research Center of Geological Hazard Prevention and Treatment Chongqing China Civil King Information Technology Company Limited Beijing China

The reinforcement effect of geogrids is exerted through the fixing and occlusion with the surrounding soil to ensure the stability of reinforced structure. Based on the friction reinforced mechanism, the geogrids play the role of anti-shear and anti-pulling. So the indexes of interface strength identified by shear and tensile tests?are?usually used to conduct the stability analysis of reinforced structure. At present, the same indexes of interface strength?areadopted in the stability analysis of reinforced structure, where only one of the anti-shearing action or anti-pulling effect of geogrid is considered, which is separated from the practical stress state of geogrids and has certain limitation. To solve the problem, the paper adjusts the interface indexes of geogrids based on the potential sliding surface and the stress state of geogrids when the failure happens. So the method of stability analysis is concluded where cyclic iterative analysis is carried out till the interface characters of geogrids and the unstable mode of the whole structure are the same. The calculation examples of reinforced soil slope in the paper shows that the method can fully reflect the reinforcement of geogrids and can complete the adoption of numerical method in the stability analysis of reinforcement structure.

关键词： Interface characters Tensile-Shear Combination Geogrid FEM Reduction Reinforcement Structure

VERTICAL DISTRIBUTIONS OF SOUND VELOCITY IN SEA FLOOR MEASURED IN SOUTH CHINA SEA AND HUANGHAI SEA

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Acta Oceanologica Sinica 1984年第1期 13-25页

作者：周志愚杜继川赵广存张学真 Institute of Acoustics Academia Sinica Beijing

This paper presents the vertical distribution of sound velocity in the first few ten meters of the sea floor measured in the South China Sea (12 stations) and the Huanghai Sea (2 stations) by reflection and refraction *** apparent characters of the sediment samples and the velocities estimated from the sample porosities by Anderson’s empirical equation basically coincide with the measured velocity structures.A new method called 'total reflected ray method' has been used to interpret the reflection data.

关键词： coincide refraction apparent floor basically travel interpret porosity characters empirical

韩日汉字音中的上古知章系与喻日母字(英文)

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语言研究 1995年第2期15卷 69-84页

作者：严翼相江原大学校中文科韩国江原道春川市

研究中国历史语言学时，所谓域外方言即韩日越汉字音的价值并不亚于中国现代方言，域外方言与中国现代方言平常都被认为基于后期中古音。但是日本汉字音中的吴音读法和闽语白读是例外。这两种方言的音系比其他域外及中国方言反映更早的... 详细信息

研究中国历史语言学时，所谓域外方言即韩日越汉字音的价值并不亚于中国现代方言，域外方言与中国现代方言平常都被认为基于后期中古音。但是日本汉字音中的吴音读法和闽语白读是例外。这两种方言的音系比其他域外及中国方言反映更早的中国语音。比较现代韩日汉字音，这些看法并不是错误的。可是根据日本吴音比韩国汉字音反映更早期的中国语音的现象来认为古代日本人比古代韩国人先接受后通用汉字可能是不对的。现代韩日汉字音系的先后问题和实际使用汉字时期上先后并没有密切关系。这等于吴语是最早派生的中国方言而现代闽语（白读）比现代吴语反映早期中国语音。因此，本文用韩国古地名中通用的汉字来例证韩国古代汉字音比日本吴音反映更早期的中国语音。比如说，韩国现代汉字音把中古知系字念成塞擦音声母，即反映后期中古音。因为知系字在日本汉字音（吴音和汉音）本来被念成舌头音，因而有人认为日本汉字音比韩国汉字音表示更早期的中国语音，可是，在韩国古地名里，“知”“珍”等中古知系字和“旦”“顿”“吞”“突”等端系字通用。由此，我们可知道韩国古代汉字音不分中古知端系。这等于说明韩国古代汉字基于中国上古音。章系在韩国现代汉字音被念成塞擦音而在日本汉字音已经变成擦音。可是韩?

关键词：韩国汉字音日母字 Chinese 英文日本吴音古地名语音现代方言 characters