应用傅里叶变换红外光谱区分鉴定四种食源性致病菌的研究

利用傅里叶变换红外光谱技术(FT-IR)对大肠杆菌O157: H7、肠炎沙门氏菌、单核增生性李斯特菌、金黄色葡萄球菌这四种典型食源性致病菌进行了研究. 对其红外谱图进行基线校正和归一化处理, 对其谱带归属进行判别分析, 选取具有菌株特性的1500～800 cm^－1的谱带, 进行一阶导数运算, 结合化学计量学方法主成分分析(PCA)和聚类分析(CA), 并进行相关系数的统计学分析, 得出以下结果: 四种食源性致病菌最大相关系数为0.937, 最小相关系数为0.058, 而且四种不同的细菌在PCA和CA分析图上也达到了很好的区分效果. 研究表明, FT-IR有望成为一种快速检测食源性致病菌的新方法.     

苯氧威 (C17H19NO4) 的热容和热力学性质

通过小样品精密自动绝热量热计测定了自己合成并提纯的苯氧威 (C₁₇H₁₉NO₄) 在79 ～ 360 K温区的低温摩尔热容。量热实验发现, 该化合物在320 ~ 330 K温区, 有一固 - 液熔化相变过程, 其熔化温度为（326.31±0.14）K, 摩尔熔化焓、摩尔熔化熵及化合物的纯度分别为：(26.98±0.04) kJ• mol^-1和（82.69 0.09）J•mol^-1•K^-1和 (99.53±0.01 )%。并计算出了80-360 K的热力学参数。用分步熔化法得到绝对纯化和物的熔点为326.60±0.06 K。用差示扫描量热 (DSC) 技术对该物质的固-液熔化过程作了进一步研究，结果与绝热量热法一致。     

3-氨基-1H-1,2,4三唑类席夫碱的合成和生物活性

以醋酸为催化剂,用3-氨基-1H-1, 2, 4-三唑与取代苯甲醛反应合成了8个3-氨基-1H-1, 2, 4-三唑类席夫碱,化合物结构经1H NMR,IR和元素分析证实,并对其进行了生物活性测试,初步生物活性结果表明此类化合物具有良好的杀菌活性。     

壳聚糖希夫碱的合成及其对灰霉菌抑菌活性研究

以壳聚糖(CTS)、水杨醛(Sal)、2-羟基-4-甲氧基苯甲醛(2-Hy)、香草醛(Val)和邻香草醛(O-val)为原料,经过缩合反应得到四种壳聚糖衍生物(CTS-Sal,CTS-2Hy,CTS-Val,CTS-O-val),采用红外光谱(FT-IR)和紫外分光光谱(UV)对结构进行了表征。通过微量液体稀释法和真菌菌丝生长速率法测定了四种衍生物对灰霉菌的最小抑菌浓度(MIC)和半抑制量浓度(EC50)。结果表明,与CTS相比,四种衍生物对灰霉菌均有明显抑制作用,其中CTS-2Hy的MIC和EC50均最小,分别为1 184.49μg·m L-1和724.44μg·m L-1。     

Synthesis,Structure and Biological Activity of 3-Methyl-4-(3-nitrobenzylideneamino)-5-ethoxycarbonyl-methylsulfanyl-1,2,4-triazole

A Schiff base was synthesized by 3-methyl-4-amino-5-ethoxycarbonyl-methylsulfanyl-1,2,4-triazole with 3-nitrobenzaldehyde. The structure was confirmed by 1H NMR, IR, H RMS, TGA techniques and X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c, with a = 8.965(2), b = 21.903(5), c = 9.197(2) A, β = 114.011(4)°, C14H15N5O4 S, Mr = 349.08, V = 1649.7(6) A3, Dc = 1.407 g·cm-3, Z = 4, F(000) = 728, μ = 0.226 mm-1, the final R = 0.0574 and wR = 0.1336 for 2932 unique reflections with I 2σ(I). Furthermore, the biological activity to four vegetable pathogens has been tested. The title compound exhibits better biological activity to four vegetable pathogens compared to the Schiff base without 5-ethoxycarbonyl and to Gibberlla saubinetti in EC95 compared with triadimefon.     

2-氯-N,N-二甲基尼古丁酰胺的热容和热力学性质研究

Low-temperature heat capacities of 2-chloro-N,N-dimethylnicotinamide were precisely measured with a high-precision automated adiabatic calorimeter over the temperature range from 82 K to 380 K. The compound was observed to melt at （342.15±0.04） K. The molar enthalpy AfusionHm, and entropy of fusion, △fusionSm, as well as the chemical purity of the compound were determined to be （21387±7） J·mol^-1, （62.51±0.01） J·mol^-1·K^-1, （0.9946±0.0005） mass fraction, respectively. The extrapolated melting temperature for the pure compound obtained from fractional melting experiments was （342.25±0.024） K. The thermodynamic function data relative to the reference temperature 298.15 K were calculated based on the heat capacity measurements in the temperature range from 82 to 325 K. The thermal behavior of the compound was also investigated by different scanning calorimetry.     

核酸适配体-荧光传感技术在重金属检测领域的应用

重金属污染环境后难以自然降解或无害化,进入有机体后有较强的生物蓄积性,会对环境安全和人类健康造成巨大威胁;此外,有些高毒重金属离子还可作为蓄意投毒、威胁恐吓的恐怖剂.因此,对环境中的重金属离子实现快速、现场检测尤为重要.传统仪器检测方法前处理复杂、成本高、操作需要专业人员,现场应用受限.近年来随着技术的发展和新材料的应...     

Experimental and Theoretical Analysis of Gradient—Index Lens Diffraction by Matrix Optics

We Present the diffraction patterns observed in the gradient-index(GRIN) lens sensor experiment.Then the diffraction pattern of radial GRIN lens is explored by using matrix optics,The theoretical results agree with the experimental results of 27.9-long GRIN lens with 2-mm diameter diffraction patterns.     

In situ calibrated angle between the quantization axis and the propagating direction of the light field for trapping neutral atoms

The recently developed magic-intensity trapping technique of neutral atoms efficiently mitigates the detrimental effect of light shifts on atomic qubits and substantially enhances the coherence time. This technique relies on applying a bias magnetic field precisely parallel to the wave vector of a circularly polarized trapping laser field. However, due to the presence of the vector light shift experienced by the trapped atoms, it is challenging to precisely define a parallel magnetic field, espe...     

光学相干性综合实验

利用双频光栅剪切干涉法，CCD摄像机采集剪切干涉条纹图，用自行设计的软件对图像进行处理，可定量测量光场的时空相干性以及梯度折射率透镜的像差。