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锰接触对新生大鼠脑发育的时空影响因素研究 被引量:1
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作者 贺新红 张德兴 《卫生研究》 CAS CSCD 北大核心 2005年第2期161-163,共3页
目的 探讨锰接触对大鼠生后脑发育过程中时程因素和区域因素 (即时、空因素 )的影响作用。方法 将新生雄性SD大鼠随机分为染锰 1月龄组、2月龄组、3月龄组和各自对照组。染锰组自出生之日起供给 10g L氯化锰的溶液自由饮食 ,对照组供... 目的 探讨锰接触对大鼠生后脑发育过程中时程因素和区域因素 (即时、空因素 )的影响作用。方法 将新生雄性SD大鼠随机分为染锰 1月龄组、2月龄组、3月龄组和各自对照组。染锰组自出生之日起供给 10g L氯化锰的溶液自由饮食 ,对照组供以自来水。 2 1日断奶后 ,取出母鼠 ,仔鼠继续供以上述溶液至处死之日止。各组动物于染锰结束后 ,采用胶质细胞纤维酸蛋白 (GFAP)免疫细胞化学染色与微机图象分析相结合技术 ,检测锰接触大鼠脑部不同时程和不同区域的胶质细胞纤维酸蛋白免疫反应情况及其反应阳性产物的平均相对密度。结果  (1)染锰 1月龄组仔鼠 ,脑部的躯体感觉皮质和躯体运动皮质的GFAP阳性产物平均相对密度与对照组相比差异无显著性 ;而内侧隔核、斜角带、杏仁复合体、苍白球和无名质等锥体外系结构的GFAP阳性产物平均相对密度与对照组相比均显著升高 (P <0 . 0 0 1)。 (2 )染锰 2月龄组仔鼠 ,脑部的躯体感觉皮质和躯体运动皮质的GFAP阳性产物平均相对密度与对照组和 1月龄组相比 ,差异均无显著性 ;而锥体外系诸结构的GFAP阳性产物平均相对密度除显著高于对照组外 (P <0 .0 0 1) ,亦明显高于 1月龄组 (P<0 .0 1)。 (3)染锰 3月龄组仔鼠 ,脑部躯体感觉皮质、躯体运动皮质和锥体外系诸结构的GFAP阳性? 展开更多
关键词 锰接触 脑发育 毒性影响 时程因素 区域因素
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Computer Programs for Prediction of Mining Area Deformation with Time Factor Taken into Consideration 被引量:2
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作者 BIALEK Jan 《Journal of China University of Mining and Technology》 2002年第1期6-11,共6页
This paper discussed the current of works on computerisation of all problems related to mining subsidence, including the time factor,carried out in the Division of Mining Geodesy of Technical University of Silesia, Po... This paper discussed the current of works on computerisation of all problems related to mining subsidence, including the time factor,carried out in the Division of Mining Geodesy of Technical University of Silesia, Poland. First, the formulas implemented in the programs were presented. These formulas considerably increase the description accuracy of final deformations by taking into uncaved strip along extraction rib (extraction margin). They also improve the deformation description of areas located far from the extraction place. Then, the research results aiming to improving the description of deformation with time were introduced. Finally, the Windows based version of the program for the creation of mining geological opinions were presented in the form accepted by Mining Offices of Poland. 展开更多
关键词 mining subsidence PROGRAM time factor
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Selection model of trip time for rural population 被引量:2
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作者 冯忠祥 袁华智 +2 位作者 刘静 高璇 张卫华 《Journal of Central South University》 SCIE EI CAS 2013年第1期274-278,共5页
Referring to the 1 248 survey data of rural population in 14 provinces of China, the influencing factors of trip time choice were analyzed. Based on the basic theory of disaggregate model and its modelling method, nin... Referring to the 1 248 survey data of rural population in 14 provinces of China, the influencing factors of trip time choice were analyzed. Based on the basic theory of disaggregate model and its modelling method, nine grades were selected as the alternatives of trip time, the variables affecting time choice and the method getting their values were determined, and a multinomial logit (MNL) model was developed. Another 1 200 trip data of rural population were selected to testify the model's validity. The result shows that the maximum absolute error of each period between calculated value and statistic is 3.6%, so MNL model has high calculation accuracy. 展开更多
关键词 traffic planning rural population trip time disaggregate model multinominal logit (MNL) model
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Specific Power Consumption as Factor Disintegration Process Control of Digging-Wheel Excavators
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作者 Josef Jurman and Jiri Fries 《Journal of Mechanics Engineering and Automation》 2013年第9期591-594,共4页
The determination of digging resistance is of decisive importance when evaluating the mining process of digging-wheel excavators. Methodic of measuring and determinant relations (formulae) are different in various c... The determination of digging resistance is of decisive importance when evaluating the mining process of digging-wheel excavators. Methodic of measuring and determinant relations (formulae) are different in various countries and by the comparison of them, underlying data for complex and objective evaluation using the knowledge from the field of rock disintegration can be obtained. In virtue of analysis of many measurements in situ, rather high specific power consumption with a wheel of excavator has been proved. What was the criterion for evaluation was the power consumption related to the volume of a rock disintegrated per unit time. From theoretical analyses, possibilities of eliminating a negative influence of the human factor upon the mining process and thus possibilities of optimum utilizing the power input of a wheel drive follow. 展开更多
关键词 WHEEL EXCAVATOR energy CONSUMPTION DISINTEGRATION digging.
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