单链多聚核苷酸的喇曼光谱及其主要谱带指认     

廖昱博  赖昭胜  许永强 《赣南师范学院学报》2010,31(3):38-40

研究了4种单链多聚核苷酸(PolyA,PolyU,PolyG,PolyC)的喇曼光谱,分析了不同盐溶液浓度对核酸主链构象的影响,并给出了各种单链核酸主要谱带的初步指认.研究表明,喇曼光谱对于研究核酸的氢键配位、主链构象和碱基堆积来说是一种强劲的工具.  相似文献   

安乃近片近红外定量分析模型的建立     

范常龙 《荆门职业技术学院学报》2010,25(9):36-37,40

目的：采用近红外漫反射光谱法对安乃近片的含量进行定量分析。方法：从某药业公司抽得安乃近片16批,在市场上购得该厂生产的安乃近片10批,经实验室检验含量是否合格。将这26批样品经内部交叉验证建立预测模型,从样品中自动选取55%为验证集,进行外部验证。结果：通过近红外测得的值跟实验室测得的值接近。结论：安乃近片用近红外漫反射光谱法预测含量,无损检测,比常规测量速度快且简便,用于药品检测及日常监管中具有可行性。  相似文献   

食品分析课程中红外光谱法教学初探     

苏学军  王建军 《泰州职业技术学院学报》2010,10(2):150-152

近年来,红外光谱分析法在我国食品分析中的应用日趋广泛,为使学校教学内容更好的与社会实际应用接轨,探讨了＂一激发、二补提、三联比＂的教学方法,帮助学生连贯知识系统,弥补教学过程中各课程间知识衔接的不足,扩大知识面,加强理论与应用的联系,较好的达到了教学目标。  相似文献   

固体螺杆清洗剂的综合分析     

吴华忠  何文绚  彭超 《闽江学院学报》2010,31(2):124-126,140

固体螺杆清洗剂是专门用于注塑成型、挤压成型及吹塑成型机螺杆和料筒清洗的产品,是机器转色、换料和维护的绝佳帮手．目前国内几乎没有高效、环保的固体螺杆清洗剂产品,所使用的产品主要依赖进口．本研究采用红外光谱、X射线粉末衍射等现代分析手段,对国外某公司的高效固体螺杆清洗剂进行了综合分析．结果表明：该固体螺杆清洗剂的载体树脂为苯乙烯类树脂、主要助剂为烷基磺酸盐类物质、烷基芳基酯类物质．此结果为国内固体高效螺杆清洗剂的研发提供重要参考,大大缩短产品研发周期．  相似文献   

ATR-FTIR imaging of albumen photographic prints     

Camilla Ricci  Simon Bloxham  Sergei G. Kazarian   《Journal of Cultural Heritage》2007,8(4):387-395

The preservation of early 20th century, late 19th century albumen prints is of great concern to collection managers and conservators of photographic materials. Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopic imaging is presented for the first time as analytical methodology for the study of albumen photographs. This paper shows the feasibility of obtaining FTIR images of samples from albumen photographs with a high spatial resolution using a Ge ATR objective coupled with an infrared microscope. The improved spatial resolution compared to FTIR images obtained by the reflection method is due to the high refractive index of the ATR crystal, which gives a high numerical aperture and hence, a higher spatial resolution. The technique reveals detailed information on the organic functional group distribution in the individual layers of embedded cross sections and is used complementary to visual microscopy and scanning electron microscopy/energy dispersed X-ray spectroscopy. The main results of the study are discussed with regard to their historical and artistic significance, and they are compared with data from historical and conservation literature.  相似文献   

评估普通人群肝脂肪变性磁共振成像定量方法的可行性     

胡斌  张杰  陈静静  李晓飞  徐文坚 《实验室研究与探索》2021,(1):45-48,63

为了探讨采用3T西门子MRI LiverLab评估普通人群志愿者肝脏脂肪含量的可行性,招募了60名志愿者,其中双回波Dixon技术预测肝脂肪变性的患病率为51.7％(31/60),多回波Dixon和多回波HISTO技术测量的平均肝脏质子密度脂肪分数分别为(9.1±1.9)％和(9.3±2.3)％,测量结果在统计学上没有...  相似文献   

The effects of 4 weeks normobaric hypoxia training on microvascular responses in the forearm flexor     

S. Fryer  K. Stone  T. Dickson  A. Wilhelmsen  D. Cowen  J. Faulkner 《Journal of sports sciences》2019,37(11):1235-1241

Intermittent exposure to hypoxia can lead to improved endurance performance. Currently, it is unclear whether peripheral adaptions play a role in improving oxygen delivery and utilization following both training and detraining. This study aimed to characterize skeletal muscle blood flow (mBF), oxygen consumption (mV?O₂), and perfusion adaptations to i) 4-weeks handgrip training in hypoxic and normoxic conditions, and ii) following 4-weeks detraining. Using a randomised crossover design, 9 males completed 30-min handgrip training four times a week in hypoxic (14% FiO₂ ~ 3250m altitude) and normoxic conditions. mBF, mV?O₂ and perfusion were assessed pre, post 4-weeks training, and following 4-weeks detraining. Hierarchical linear modelling found that mV?O₂ increased at a significantly faster rate (58%) with hypoxic training (0.09 mlO₂·min^?1 · 100g^?1 per week); perfusion increased at a significantly (69%) faster rate with hypoxic training (3.72 μM per week). mBF did not significantly change for the normoxic condition, but there was a significant increase of 0.38 ml· min^?1 · 100ml^?1 per week (95% CI: 0.35, 0.40) for the hypoxic condition. During 4-weeks detraining, mV?O₂ and perfusion significantly declined at similar rates for both conditions, whereas mBF decreased significantly faster following hypoxic training. Four weeks hypoxic training increases the delivery and utilisation of oxygen in the periphery.  相似文献   

固态氨基酸的THz时域光谱研究     

徐慧  余笑寒  张增燕  韩家广  李晴暖  朱志远  李文新 《中国科学院大学学报》2005,22(1):90-93

利用太赫兹时域光谱室温下对手性对映体D 酪氨酸、L 酪氨酸、外消旋化合物DL 酪氨酸和D 色氨酸、L 色氨酸、外消旋化合物DL 色氨酸在 0 1～ 2 0THz频谱范围内进行了光谱测量。结果表明,所研究的氨基酸在此波段有特征吸收峰,THz时域光谱能够鉴别对映异构体和他们的外消旋化合物。  相似文献   

橙皮素的制备     

李丹  毕丁文  杨璐  陈宁  侯玺康  秦婷  王卫博  于宏伟 《石家庄学院学报》2014,(3):19-22

橙皮素是一类重要的天然黄酮类化合物.报道了由橙皮苷制备橙皮素的方法,并对其反应机理进行研究.采用一维红外光谱和二阶导数红外光谱对橙皮苷和橙皮素的结构进行了表征.  相似文献   

紫外光谱技术在食品分析中的应用     

肖益  吕重莹  加平平  史佳伟 《渭南师范学院学报》2014,(7):93-96

紫外光谱技术是化学分析中常用的一种方法,被广泛用于有机、生化、石油、药物、环境等领域,其在食品分析中的应用包括紫外光谱法在鉴别食品中的应用,具体为鉴别食品含量、食品质量和食品种类方面的应用．紫外可见光谱分析技术具有速度快、效率高、成本低、测量方便等特点,已经被越来越多地应用于食品工业,应用前景广泛．  相似文献