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21.
合成和表征了一个新的吡啶衍生物溴化(E)-1,1′-(六烷-1,6-二甲氨基)二(4-(E)-2-(噻吩基)乙烯基吡啶,这是一种自组装膜合成的中间配体,具有特殊的结构特征和氧化还原性,以其为配体继续合成自组装膜材料,在共价和静电自组装膜研究的领域有很高的研究价值,本文对它的合成、表征及其紫外可见光谱和荧光光谱等的性质作一研究。  相似文献   
22.
葡萄糖浓度检测在治疗糖尿病过程中起着重要作用,采用近红外光谱方法测量葡萄糖浓度是国内外研究的热点.通过实验的方法,用800nm到1600nm的近红外光照射葡萄糖水溶液,对不同葡萄糖浓度对应的能量谱进行分析,发现在1111nm处的吸收峰特征比较明显,与葡萄糖浓度有着对应的关系,通过指数曲线拟合,建立葡萄糖浓度检测的数学模型.  相似文献   
23.
Adaptive functioning skills, also known as adaptive behaviours, refer to a multifaceted concept defined as behaviours necessary for age-appropriate, independent functioning in social, communication, daily living or motor areas. In light of the growing population of children with ASD who will eventually become adults, increased understanding of adaptive functioning during the transition to adulthood is of importance, but current research in this area lacks first-hand evidence presenting adaptive skills difficulties among older adolescents and adults with ASD. This article focuses on adaptive functioning skills in daily transitions for adults with Asperger’s syndrome (AS) or high-functioning autism (HFA). It draws on evidence from 12 interviews with individuals on the autism spectrum age 16–43, and 2 focus groups with 8 family members of people affected by ASD. Particular emphasis is placed on impact of adaptive functioning difficulties on well-being and quality of life for adults with ASD. Grounded theory approach has been used to analyse the gathered data. Interviewees reflected on daily challenges associated with unexpected changes in routine, sensory difficulties and social interactions. These in turn had an impact on their adaptive functioning skills by introducing complications in the process of making transitions between different contexts and decreasing interviewees’ ability to tackle challenges of daily life. Importance placed on societal expectations towards meeting bespoken standards and conforming to norms ruling the structure and interactions of daily life were also widely discussed. Frequently such expectations did not allow for factoring in the developmental nature of ASD and related difficulties, which as a result triggered additional complexity in managing daily transitions for adults on the spectrum. Further research addressing adaptive functioning skills in daily transitions for adults with ASD is needed.  相似文献   
24.
Infrared (IR) absorption spectra and X-ray powder diffraction (XRD) patterrns of sexpenfine cat's eye from Sichuan Province have been investigated, and infrared absorption bands of the serpentine have been assigned in this paper. The results indicate that the bands near 3 600 - 3 700 cm^-1 belong to the stretching absorption band VOH, the bands in 948 - 1 100 cm^-1 axe assigned to the stretching vibraling band Usvo, and the bands at 600 570 and 440 cm^-1 respectively belong to the bending vibration band VOH, δMg-O and δSi-O. The serpentine cat' s eye includes two types: chrysotile and antigorite. Chrysotile has a sharp and intensive band at 3 688 cm^-1 and a weak band at 3 643 cm^-1 , while antigorite has only one intensive band in the region. At vibration band VSi-O, chrysotile and antigorite have a similar feature at 1 071 cm^-1, but the band at 980 cm^-1 in anfigorite has been split into two bands in chrysotile - a strong one at 1 027 cm^-1 and a weak one at 949 cm^-1. In addition, antigorite has a characteristic bending vibrating band δMg-O at 570 cm^-1. Based on the analysis of the feature of crystal structure, their IR differences axe well explained.  相似文献   
25.
本文证明了PVDF与at-PMMA共混物中两者之间非常弱的相互作用 .随着PVDF质量分数的提高 ,共混物显示出更为异相的性质 .通过红外光谱的示差扫描技术 ,减去共混物谱图中PVDF和at-PMMA的谱图 ,显示在高PVDF含量时 ,υc=o吸收峰向低波数移动 ,表明它们之间的相互作用存在于PMMA的羰基和PVDF的H原子之间 .接触角测量表明随着PVDF含量的提高 ,膜的憎水性增强 .当PVDF的含量超过 30 % (质量 % )时 ,对水的接触角大于 90° ,显示了优异的憎水性 .但是 ,膜可以被正己烷完全润湿 ,因而对正己烷的接触角测量不到  相似文献   
26.
孤独症相关脑机制的研究现状   总被引:1,自引:0,他引:1  
从脑生理机制的角度对孤独症进行研究已成为当前孤独症研究的热点。脑生理机制研究方面,以LYNN WATERHOUSE等人提出的思辨模型最具有代表性和概括性,能够较全面系统地对孤独症的行为特征作出解释,后继的研究也较好地支持了他们的模型。通过分析,对今后孤独症研究的趋势提出了一些展望。  相似文献   
27.
元代文论专著并不丰富,有特色之论更不多见,陈绎曾的《文筌》却是一部较为有个性的批评专著,其中《古文谱》和《古文矜式》对古文的创作、风格、鉴赏都有集中的论述,代表着元代古文批评的价值取向。  相似文献   
28.
天然甘蓝食用色素化学稳定性研究   总被引:3,自引:0,他引:3  
蔬菜花色素是天然食用色素中的一个主要类别,属水溶性色素.甘蓝色素是蔬菜花色素中新近开发的一种.本文测定了甘蓝色素吸收光谱和其在溶液中呈现红紫色的适宜酸度条件,观察了不同pH对该色素的影响和这些添加剂存在下它的光照稳定性.为甘蓝色素的开发应用提供了依据.  相似文献   
29.
This longitudinal case study of a 10‐year‐old girl with autism and severe communication impairment measures the impact of the MORE (Means, Opportunities, Reasons and Expectations) approach to enhancing engagement and communication. Through detailed observation of video data over a period of 28 months, engagement behaviours including interaction with adults and following adult directions increased, while resistant behaviours such as kicking, hitting and pushing adults away decreased. Fluctuation between different ‘states’ demonstrated that the frequency and duration of engagement was influenced by the MORE approach and an emphasis on developing intrinsic motivation. In order to enable further efficacy research, core features of the intervention and the changes in engagement over time are described.  相似文献   
30.
布里渊散射是光纤通信原理课程讲解过程中涉及到的一个非常重要的非线性效应。鉴于理论复杂、学生难于理解的教学现状,利用国家高技术研究发展计划(863)建设的光纤传感创新平台,设计了一套光纤布里渊散射光谱演示实验系统,便于学生形象直观地学习。给出了具体的实验系统、实验操作过程以及实验结果,并对比了4种光纤的布里渊散射频谱图。该实验系统在教学中取得了非常好的效果。  相似文献   
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