含氟香豆素透明质酸衍生物的合成及其荧光性能

以间氨基苯酚与三氟乙酰乙酸乙酯反应生成4-三氟甲基-7-氨基香豆素,其与氯乙酰氯反应生成-4-三-氟甲基-7-氯乙酰氨基香豆素。 该化合物与透明质酸钠反应得到了含氟香豆素透明质酸衍生物。 利用荧光光谱等分析技术研究了浓度、pH值和温度变化对该透明质酸衍生物荧光强度的影响,同时研究了金属离子对其荧光强度的影响。 结果表明,一定浓度范围内,荧光强度随透明质酸衍生物浓度增大而逐渐增强;在pH值为3.86～8.85范围内,其荧光强度较为稳定;在10～80 ℃范围内,其荧光强度随温度的升高而逐渐减弱;在常见干扰离子存在下,Fe3+对其荧光强度有较为显著的影响,其荧光强度显著降低。 这为探索透明质酸在生命机体内的药物载体机理及其靶向作用提供良好的实验基础。     

原子转移自由基聚合法制备新型亲水开管毛细管柱及在毛细管电色谱上的应用

为了增加开管毛细管柱(OTCC)的相比,提高分离效率,发展了表面引发原子转移自由基聚合法(SI-ATRP)制备葡萄糖聚合物修饰的开管毛细管柱。通过扫描电镜观察,该开管柱内壁上修饰了三维波浪状聚合物,明显增加了内壁比表面积和相比。在pH 3~11范围内,对含糖聚合物修饰的开管柱和空柱的电渗流进行了比较。修饰后开管柱的电渗流仅为空柱的1/2~1/3,且在pH 6~11范围内保持平稳。稳定的电渗流保证了分离的重复性和稳定性。用该开管毛细管柱成功实现了小分子混合物(苯丙氨酸、胸腺嘧啶、腺苷、鸟苷、5-溴尿嘧啶、水杨酸)以及蛋白质大分子(核糖核酸酶B、转铁蛋白和牛血清白蛋白)的有效分离,结果表明葡萄糖聚合物修饰的开管毛细管柱具有良好的重复性和稳定性。     

不同本构模型对橡胶制品有限元法适应性研究

为确定不同本构模型对橡胶制品进行非线性有限元分析的适应性,采用HyperMesh 和ABAQUS软件建立了橡胶标准试件和防尘罩制品的非线性有限元模型. 根据标准试件单轴拉伸试验数据,利用ABAQUS软件拟合了Mooney--Rivlin, Ogden 及Yeoh 3 种本构模型的特征参数,并给出了试件和制品轴向拉伸和压缩工况有限元分析结果. 实测试验与有限元分析结果对比发现:在应变不大于100% 时,两参数的Mooney--Rivlin本构模型计算误差较小;在应变大于100% 时, 用Yeoh 和Ogden 本构模型计算误差较小. 该结论对大变形橡胶元件的非线性特性理论分析具有实际意义.     

A method to correct optical fiber's spectrum attenuation based on Fourier transform in spectra-measuring systems

A method based on Fourier transform to revise the non-linear spectrum attenuation of optical fiber used as a probe in a spectrum-measuring system is proposed in this paper. Spectral curves of a normal light source are measured by a spectrum-measuring system with and without the optical fiber probe, respectively. The generalized frequency spectrum (GFS) of these spectral curves can be calculated based on Fourier transform. From them, an optical fiber spectrum correction function can be obtained and the non-linear spectrum attenuation of optical fiber can be revised with the SCF. The experiment results show that the method has the accuracy of 1% and it is more accurate than the Ratio Method (RM) and the Weighted Ratio Method (WRM).     

南海黄蜂海绵中系列长链甲基酮成分分析

从中国南海海绵Spheciospongia Vagabunda乙酸乙酯萃取部分中分离出一组混合物,应用^13HNMR,^13CNMR,H-HCOSY和GC／MS等光谱分析技术对它们的结构进行了分析,主要为一些长链甲基酮化合物。共鉴定出二十四碳烯-2-酮异构体、二十四碳二烯-2-酮和二十四碳烯-2-酮等14种化合物,其中4种化合物的双键位置有待于进一步确定。     

Tm3+:NaLa(MoO4)2晶体的1.9 μm准连续激光输出

以0.94 mm厚的c切片7.5%(原子分数)Tm3+:NaLa(MoO4)2晶体为增益介质,采用795.5 nm波长钛宝石激光泵浦,实现了1.9 μm准连续激光输出.当输出镜透过率为6.6%时,激光起振阈值为60 mW,斜率效率为50%,最大输出功率为0.5 W.输出激光波长随输出镜透过率的增大向短波方向移动.实验结果表明,Tm3+:NaLa(MoO4)2晶体是一种性能优良的1.9μm波段激光晶体.     

结构力学虚拟仿真实验教学研究

基于结构力学实验,应用Flash开发系统建立了结构力学实验的虚拟实验环境和虚拟实验物理的模型.通过将实验对象的数学模型引入到虚拟实验对象状态控制程序的方法,实现了对结构力学虚拟实验对象的实时判断和实际数据库的动态链接,使虚拟实验系统具有完好的交互性和实验现象、规律、实验结果的准确性.为加强实践教学环节提供了另一种实验教学的手段,为力学实验教学网络化提供了可视资源.     

香豆素并咔唑基草酸酯类UV-LED可激发光引发剂的合成与研究

本文设计并制备了以香豆素并咔唑为共轭结构的草酸酯类光引发剂（2-OAME和4-OAME）,分子中大π-共轭结构的引入实现了分子在LED光域的良好吸收。通过核磁共振谱对目标产物进行了结构验证,通过紫外-可见吸收光谱、荧光光谱和理论计算对分子的光化学及光物理性质进行了表征。研究表明,两个光引发剂在近紫外-可见光范围内均表现出优异的光吸收性质,并且在LED光源激发下具有良好的光引发聚合能力,4-OAME分子较2-OAME在同样的条件下表现出更好的光引发聚合能力,在近紫外-可见LED光聚合领域具有较大的应用潜力。     

CT/MRI‐Guided Synergistic Radiotherapy and X‐ray Inducible Photodynamic Therapy Using Tb‐Doped Gd‐W‐Nanoscintillators

The use of X‐rays instead of UV/Vis light to trigger photodynamic therapy, named X‐ray inducible photodynamic therapy, holds tremendous promise due to a high penetration capacity in tissues and is worthy of in‐depth study. In this study, a novel multifunctional nanoagent based on Merocyanine 540‐coupled Gd₂(WO₄)₃:Tb nanoscintillators and the vitalization of its abilities for dual‐modal computed tomography and the magnetic‐resonance‐imaging‐guided synergistic radio‐/X‐ray inducible photodynamic therapy of tumors is reported. Synergistic therapies show a higher tumor growth inhibition efficiency at a lower X‐ray dose than radiotherapy alone. Through this proof‐of‐concept work, a way to tactfully understand and utilize nanoscintillators for cancer theranostics is shown.     

Crystal Multi‐Conformational Control Through Deformable Carbon‐Sulfur Bond for Singlet‐Triplet Emissive Tuning

Crystal‐state luminophores have been of great interest in optoelectronics for years, whereas the excited state regulation at the crystal level is still restricted by the lack of control ways. We report that the singlet‐triplet emissive property can be profoundly regulated by crystal conformational distortions. Employing fluoro‐substituted tetrakis(arylthio)benzene luminophores as prototype, we found that couples of molecular conformations formed during different crystallizations. The deformable carbon‐sulphur bond essentially drove the distortion of the molecular conformation and varied the stacking mode, together with diverse non‐covalent interactions, leading to the proportional adjustment of the fluorescence and phosphorescence bands. This intrinsic strategy was further applied for solid‐state multicolor emissive conversion and mechanoluminescence, probably offering new insights for design of smart crystal luminescent materials.