藏红T在阴离子表面活性剂十二烷基硫酸钠上的Langmuir吸附研究

微相吸附 -光谱修正 (MPASC)技术研究了十二烷基硫酸钠 (SLS)与藏红 T(ST)的结合反应 ,分析表面活性剂在微量分析中的增效机理。结果表明 :ST- SLS间相互作用符合 Langmuir单分子层吸附机理 ,产物结合比约为 1∶ 1。     

去甲万古霉素键合手性固定相的制备及其对磷酸苯并哌啉对映异构体的拆分

制备了去甲万古霉素键合手性固定相以及由苯基异氰酸酯衍生化去甲万古霉素键合手性固定相,并在极性有机相模式下对磷酸苯并哌啉进行了手性拆分的研究。发现在此模式下,衍生化去甲万古霉素键合手性固定相对磷酸苯并哌啉的手性选择性要优于没有衍生的去甲万古霉素键合手性固定相;在衍生化去甲万古霉素键合手性固定相上详细考察了流动相组成、酸碱添加剂用量、温度以及流速对分离的影响,优化了分离的条件。在优化的实验条件下,磷酸苯并哌啉可获得基线分离。     

Selective Benzylic and Allylic Alkylation of Protic Nucleophiles with Sulfonamides through Double Lewis Acid Catalyzed Cleavage of sp3 Carbon–Nitrogen Bonds

The acid‐catalyzed benzylic and allylic alkylation of protic nucleophiles is fundamentally important for the formation of carbon? carbon and carbon? heteroatom bonds, and it is a formidable challenge for benzylic and allylic amine derivatives to be used as the alkylating agents. Herein we report a highly efficient benzylic and allylic alkylation of protic carbon and sulfur nucleophiles with sulfonamides through double Lewis acid catalyzed cleavage of sp³ carbon–nitrogen bonds at room temperature. In the presence of a catalytic amount of inexpensive ZnCl₂‐TMSCl (TMSCl: chlorotrimethylsilane), 1,3‐diketones, β‐keto esters, β‐keto amides, malononitrile, aromatic compounds, thiols, and thioacetic acid can couple with a broad range of tosyl‐activated benzylic and allylic amines to give diversely functionalized products in good to excellent yields and with high regioselectivity. Furthermore, the cross‐coupling reaction of 1,3‐dicarbonyl compounds with benzylic propargylic amine derivatives has been successfully applied to the one‐step synthesis of polysubstituted furans and benzofurans.     

1-[（6-烷（苄）氧基-3，4-亚甲二氧基）苯基]-2-（1H-1，2，4-三唑）-乙酮（醇）类化合物的合成及抑菌活性

以3,4-亚甲二氧基苯酚和1-H-1,2,4-三唑为主要原料,合成了12种1-[(6-烷(苄)氧基-3,4-亚甲二氧基)苯基]-2-(1H-1,2,4-三唑)-乙酮(醇)类化合物.化合物经IR、1H NMR、13C NMR、元素分析测试技术进行了表征确证.初步牛物测试结果表明,在质量浓度为1×10-4g/mL下,化合物Vc对小麦赤霉病菌的抑制率达81.3%;化合物Ⅳe对马铃薯干腐病菌的抑制率达83.4%;化合物Ve、Vf对玉米弯孢病菌的抑制率分别达79.7%和72.4%.     

Facile preparation of methylcellulose/poly(vinyl alcohol)physical complex hydrogels with tunable thermosensitivity

Novel complex hydrogels of methylcellulose(MC)and poly(vinyl alcohol)(PVA)with wide-spectrum thermoresponsivity were prepared via physical and mild process.Thermal phase transition of MC/PVA hydrogels exhibited two forms including sol/sol to gel/sol and sol/gel to gel/gel.The phase transition temperature of MC/PVA solution ranged from 38.7 to 60.6℃and was able to be adjusted by simply changing the feeding ratios of two components.The interior morphology of MC/PVA gels was examined with fluorescence analy...     

Large-area unmodified superhydrophobic copper substrate can be prepared by an electroless replacement deposition

Using an electroless replacement deposition method, large-area superhydrophobic metal substrate could be obtained. The superhydrophobic surfaces were prepared via a replacement reaction between copper substrate and HAuCl(4) solution. The roughness of the copper substrate increased much after the replacement reaction. X-ray powder diffraction (XRD) pattern and energy dispersive X-ray (EDX) spectroscopy have proved that gold, CuCl and Cu(2)O formed on the surface of copper substrate after the replacement reaction. The surface showed remarkable superhydrophobic properties with a contact angle higher than 150 degrees without any modification with a self-assembled monolayer (SAM) of long chain thiol or perfluoro molecules.     

氢键受体与供体数目比与溶质浓度的关系

利用分子动力学方法, 对不同浓度下的甘油水溶液进行了模拟, 分析了溶液的密度和氢键. 模拟得到的密度值与实验值吻合良好, 误差均在5%以内. 研究发现, 水的总受体个数与总供体个数的比值Ф与甘油的浓度cg存在线性关系. 随着溶液浓度的增大, Ф值不断下降, 而其下降值与溶液浓度存在线性关系, 即Ф(0)－Ф(cg)＝bcg.     

刚性杆-弹簧摆模型复杂动力学特性的数值仿真

建立一种刚性杆-弹簧摆刚柔耦合强非线性动力学系统模型,给出了无量纲的动力学微分方程．该模型同时存在小幅度快速振荡和大范围慢速摆动的快、慢双时间尺度变量．针对工程中此类系统数值求解容易产生的刚性问题,采用一种三次Hermite插值精细积分法进行数值计算．将频率比、摆长比和初始摆角作为控制参数,研究刚性杆-弹簧摆刚柔耦合系统快、慢变量的复杂动力学行为．通过数值仿真分析,发现系统在不同的控制参数组合下呈现出混沌运动状态,并给出了与系统运动状态相关的控制参数范围,为复杂的刚柔耦合多体系统的设计与数值分析提供了参考．     

溅射气压对碳硅氧薄膜透过率及光学带隙的影响

采用射频磁控溅射技术在玻璃基底和单晶硅片(100)上制备了碳硅氧(SiOC)薄膜,通过扫描电镜、X射线衍射、拉曼光谱、X射线光电子能谱及紫外可见透射光谱等技术手段对其进行了分析,研究了在不同溅射气压下所制备薄膜的组分、透过率及光学带隙.结果表明:随着溅射气压的增大,薄膜内部sp3键含量、透过率及光学带隙均随之增大,sp3键及其形成的宽带隙σ键对薄膜光学带隙有着较大影响.在溅射气压为3.0 Pa的条件下,薄膜光学带隙为2.67 eV.     

脉冲激光烧蚀材料等离子体反冲压力物理模型研究与应用

分析了脉冲激光烧蚀材料等离子体等温膨胀阶段的物理特性,建立了脉冲激光烧蚀材料等离子体压力三维方程与动力学模型.应用所建模型,数值分析了单脉冲激光烧蚀青铜金刚石砂轮等离子体相关特性,得到等离子体的反冲压力最大值870 Pa出现在约25 ns后,距离砂轮表面距离约0.05 mm处.相关条件下开展脉冲激光烧蚀青铜金刚石砂轮试验,采用高速相机观测烧蚀砂轮过程中的飞溅现象;采用光栅光谱仪测量等离子体空间发射光谱,计算了等离子体电子温度、电子密度以及反冲压力.实验表明脉冲激光烧蚀青铜金刚石砂轮等离子体反冲压力可以不计,同时也验证了气体方程与动力学模型的正确性和可行性,对脉冲光纤激光烧蚀工艺优化具有启示意义.