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51.
目的::探讨游泳运动员短时间高强度间歇训练过程中肌肉氧参数动态变化特征和规律,以及训练前后的血乳酸( LA)、心率( HR)、主观疲劳感觉( RPE)变化及相关性。方法:随机选取山东省游泳运动员(n=15)采用短时间高强度间歇训练模式,全力蹬踏功率自行车30秒、休息120秒、重复进行3次为一组、共2组,组间休息3-4分钟。连续监测受试者短时间高强度间歇训练过程中股外侧肌组织肌氧参数变化;每次全力蹬踏30秒后即刻测试受试者RPE;整个训练过程中实时同步监测HR,并于每次全力蹬踏30秒后即刻读取并记录受试者HR;分别在训练前后即刻取受试者指尖血10μL,测试LA值。结果:(1)全力蹬踏功率自行车过程中股外侧肌组织氧合血红蛋白含量( CHbO2)和局部组织肌氧饱和度( TOI)迅速下降、肌组织还原血红蛋白( CHb )迅速上升;(2)两组短时间高强度间歇训练后LA、HR、RPE都分别显著高于训练前(P<0.01);(3)训练前后的LA、HR、RPE之间具有高度相关性(P<0.01)。结论:(1)可通过近红外光谱技术监控短时间高强度间歇训练过程中肌组织中CHbO2、CHb、TOI动态变化趋势;(2)在短时间高强度间歇训练过程中,可以通过LA、HR、RPE直接有效地监控训练的强度。  相似文献   
52.
介绍了基于AT89S52单片机,利用红外传感器直流电机的转速,控制直流电机的转动速度,用PWM调速方式控制直流电机转动的速度,以及停止转动,并可以自动调节速度至预先设定的速度。整个系统的电路逻辑结构简单,可靠性高,实现功能强。  相似文献   
53.
介绍一种通用型红外遥控控制器的设计原理.同时对该控制器的实际应用和功能扩展做了较全面的分析.  相似文献   
54.
本文提出了一种基于单片机信号处理技术的防盗检测器的软硬件设计方法。利用热释电红外传感器的红外辐射与红外探测原理,设计的新型探测器,测量范围广,响应速度快,灵敏度高,抗干扰能力强,安全可靠。  相似文献   
55.
阐述了红外光谱的不熔不溶固体样品制备技术,并用实例介绍了其在研究工作中的应用。  相似文献   
56.
The present work reports on a spectroscopic study of white colour samples collected from Etruscan polychromes on terracotta from the Cerveteri area. In particular, both white-on-red potsherds of the Orientalising period and high-value polychromes of the Archaic period were considered. The white pigment, a fundamental element in this class of artworks, was not clearly identified in previous archaeological and analytical studies, although the use of kaolin was tentatively proposed. Therefore, samples from the Monte Sughereto kaolin quarry in the Cerveteri area were also studied. The results of detailed analyses carried out using micro-Raman spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy first show that the quarry material is a high-purity kaolin containing quartz. Raman results strongly suggest that the same kind of kaolin was employed in the polychromes of the Archaic period. As to white-on red potsherds, infrared results have a key role in showing that the white pigment is a kaolin closely corresponding to the quarry material since a particular kaolin polytype (dickite) is dominant in both cases. The present work thus provides the first definitive identification of the white pigment used in Etruscan polychromes on terracotta from the Cerveteri area, and suggests that the source of kaolin might be the Monte Sughereto quarry.  相似文献   
57.
试验研究了在发动机喷管中加装金属辐射板前后,喷管壁面温度、热喷流温度与喷管红外辐射特征的变化。结果表明,加装金属辐射板后,热喷流与喷管壁面之间的热量传递显著增强,热喷流中心温度降低,壁面温度明显升高,在90°方向上,热喷流3~5μm波段的红外辐射强度降低了38.5%。文中从热喷流、喷管壁面以及金属辐射板等相关部件的温度变化情况对红外辐射强度的变化原因进行了解释。   相似文献   
58.
《文物保护研究》2013,58(2):97-106
Abstract

The Danish sculptor Anne Marie Carl-Nielsen (1863–1945) often prepared three-dimensional models in wax before producing her works of art. The Carl Nielsen Museum in Odense keeps a unique collection of around 200 of the artist's fragile wax models. In 2008 the entire collection was examined, documented, X-ray radiographed, photographed, and conserved. Analyses of five figurines by attenuated total reflectance-Fourier transform infrared spectroscopy, optical microscopy, and scanning electron microscopy-energy dispersive X-ray spectroscopy showed two different kinds of wax mixtures, one containing beeswax and potato or maize starch as filler, and the other consisting of gypsum, zinc stearate, and a greasy substance. During the examination a specific deterioration phenomenon was noticed in the areas where the wax models had been strengthened with internal metal armatures. A chemical reaction between the wax mixture and the copper containing armature has caused an intense greenish colouring of the wax as well as creating a soft and almost liquid consistency and formation of copper(II) carboxylate salts. Based on an original recipe from Anne Marie Carl-Nielsen, a replica of one of the wax mixtures was produced and examined with respect to its infrared spectrum and its modelling properties.  相似文献   
59.
Assessment of multi-leaf stone masonry in earthquake-prone areas is mostly related to the evaluation of its texture, morphology, leaf detachment and structural cracking due to previous seismic activity, as well as disintegration due to material deterioration. For the plastered masonry with heritage or artistic value (paintings, frescoes etc.), both the type of structure and the extent of damage should be characterized with minimal interference to the structure, which could be overcome solely by non-destructive testing (NDT). However, due to the complexity of plastered multi-leaf masonry structure, the performance of well-known NDT methods could be significantly worsened. Therefore, as a prerequisite for applying NDT on multi-leaf stone masonry in practice, a validation process should be carried out. In this study, complementary ground penetrating radar (GPR) and infrared (IR) thermography measurements on plastered laboratory three-leaf stone masonry walls were performed. Apart from assessing the wall texture and morphology with the type of connection between the leaves, detection of gradual plaster delamination and crack propagation while subjecting the walls to an in-plane cyclic shear test was taken into account. The results showed that GPR could successfully visualize header stones passing through the whole depth of the specimen. The masonry texture behind the plaster could be well resolved by both methods, although GPR near-field effects worsened its localisation. For the detection of plaster delamination, IR thermography outperformed GPR by detecting delamination as small as 2 mm as well as structural crack patterns, whereas GPR only detected delamination larger than 8 mm. It was shown that the performance of both methods for defect detection could be further improved by image fusion based on unsupervised clustering methods.  相似文献   
60.
主要介绍红外光谱技术在材料科学、环境科学、矿物学、农业科学、食品科学及医学等学科领域的应用。  相似文献   
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