极端气温条件下空调建筑能耗状况的模拟与分析

本文分析了极端气温条件下空调建筑热状况研究的必要性，并建立了外墙外表面热平衡模型、壁体传热模型、外墙内表面热平衡模型和室内空气热平衡模型，以北京市各种气象条件下，通过联立求解的方式，最终掌握建筑的能耗状况。结果表明上述模型能较好的反应极端气候条件下空调建筑的热特性，并可为空调建筑能耗状况的整体评价提供保障。     

自适应人工蜂群优化极限学习机在拉曼光谱血液定量分析中的应用

提出了一种基于自适应差分进化人工蜂群优化极限学习机预测血液各组分浓度的方法。首先应用人工蜂群算法对输入权值和隐含层阈值迭代寻优;其次结合差分进化进一步提高模型精度且避免后期易陷入局部最优等问题;由于差分进化算法交叉率和变异率存在凭经验给定的不确定性,最后引入了自适应调整的思想提出自适应差分进化人工蜂群算法优化极限学习机算法的模型,将其应用于血液成分定量分析中。实验表明,自适应差分进化人工蜂群算法优化的极限学习机模型具有较高的预测精度,模型具有较强的稳健性。     

非晶金刚石薄膜的拉曼光谱研究

碳离子的能量是影响非晶金刚石薄膜结构和性质最关键的工艺参数．采用磁过滤真空溅射离子技术,研究不同衬底偏压Ｖ_ｂ（即不同碳离子能量）下制备的非晶金刚石薄膜的拉曼光谱和表面形貌．结果表明：－５０Ｖ≤Ｖ_ｂ≤－１０Ｖ时,样品表面均匀、光滑,拉曼谱是对称且很宽的散射带;Ｖ_ｂ＞－１０Ｖ或Ｖ_ｂ＜－５０Ｖ时,已有晶团出现,表面粗糙度明显增加,拉曼谱明显地分裂为１５８０ｃｍ^－１的Ｇ带和１３５０ｃｍ^－１的Ｄ带．     

Theory of Ultra-high-resolution Optical Raman Ramsey Spectroscopy

A non-perturbative theoretical analysis of Ramsey interference lineshapes in three-level lambda systems excited by laser fields has been developed for the general case of several interaction regions. In conventional Ramsey excitation, two laser fields excite the lambda system each in two separate spatial interaction regions. Here we examine how increasing the number of interaction regions or altering the interaction times change and improve the lineshape characteristics such as fringe visibility. For short interaction times the fringe pattern is strongly dependent on the number of interaction regions, with the n = 2 sinusoidal fringes replaced by sharper fringes of greater visibility. With larger interaction times, the fringe pattern is virtually unchanged on increasing the number of interaction regions. The optimum fringe pattern is obtained with short interaction times and a larger (n a 9) number of regions.     

基于差分拉曼光谱对烟盒物证检验

目的 为了探究一种基于光谱分析的检验方法,以达到快速准确地区分检验烟盒物证的目的.方法 采用便携式差分拉曼光谱仪,对39个不同的黄色烟盒样本进行测试,取得各样本的差分拉曼光谱数据.根据烟盒填料种类对样本进行初步分类,再结合化学计量学,通过IBM SPSS Statistics 26.0软件,在主成分分析法对数据进行降维的基础上,对测量结果进行系统聚类和K-Means聚类.结果 39种样本依据填料种类可以区分为3类,结合化学计量学可以更准确地区分为6类.结论 该方法无损检材、快捷准确,且图谱不受荧光干扰,结合化学计量学方法可以对烟盒样本进行分类检验,此方法为公安机关在犯罪现场检验此类物证提供了依据.     

High-Resolution Stimulated Raman Gain Spectroscopy of Parahydrogen Crystals

High-resolution stimulated Raman gain spectroscopy of the Q₁(0) transition of para-H₂ crystals with varying ortho-H₂ concentrations is reported. A crystal containing 0.06% of ortho-H₂ showed a single sharp Raman transition with the width of less than 7 MHz. The Raman signal became broader with increasing concentration of ortho-H₂. At the concentration of 2%, the spectrum splits into a doublet. The components of the doublet have different dependence on the relative polarization of the pump and probe laser radiations. Physical origin of the splitting and the polarization dependence is yet to be understood.PACS numbers: 33.20 Fb, 42.65 Dr, 67.80 −s     

Estimation of Young's Modulus of Graphene by Raman Spectroscopy

The Young's modulus of graphene is estimated by measuring the strain applied by a pressure difference across graphene membranes using Raman spectroscopy. The strain induced on pressurized graphene balloons can be estimated directly from the peak shift of the Raman G band. By comparing the measured strain with numerical simulation, we obtained the Young's modulus of graphene. The estimated Young's modulus values of single- and bilayer graphene are 2.4 ± 0.4 and 2.0 ± 0.5 TPa, respectively.     

表面增强拉曼光谱技术在纳米材料研究中的新进展

表面增强拉曼光谱是一种探测界面特性和分子之间相互作用、表征分子吸附行为和分子结构非常有效的现代测试分析工具.综述了表面增强拉曼的基本原理、发展历程以及在新型活性基底、碳纳米管、表面界面、单分子体系等研究领域中的应用,并展望了表面增强拉曼未来的发展方向.     

FCVA制备超薄类金刚石薄膜的拉曼光谱分析

采用FCVA方法制备厚度分别为50nm、30nm、10nm、5nm、2nm的DLC薄膜,利用可见光拉曼光谱分析薄膜的G峰位置、Id/g和Ag/Ad,发现随着薄膜厚度的减小,Id/Ig不断增大,AgAd减小,G峰位置向低波数方向移动.紫外拉曼光谱分析结果表明,薄膜厚度减薄会减小It/Lg使T峰位置向高波数方向移动.结合两种不同波长的拉曼光谱进行分析,G峰偏移量随薄膜厚度减小呈下降趋势;随薄膜厚度的减小,FCVA法制备的类金刚石薄膜中的sp3键含量减少,同时有序化的sp2团簇增加.EELS结果也证实,薄膜厚度的减小会减少薄膜中sp3键的含量.对于50nm和30nm的非晶碳膜,拉曼光谱分析的结果与薄膜硬度和内应力实际测试结果存在一致的对应关系.