Theoretical study on the mechanism for the excited-state double proton transfer process of an asymmetric Schiff base ligand

Excited-state double proton transfer (ESDPT) in the 1-[(2-hydroxy-3-methoxy-benzylidene)-hydrazonomethyl]-naphthalen-2-ol (HYDRAVH₂) ligand was studied by the density functional theory and time-dependent density functional theory method. The analysis of frontier molecular orbitals, infrared spectra, and non-covalent interactions have cross-validated that the asymmetric structure has an influence on the proton transfer, which makes the proton transfer ability of the two hydrogen protons different. The potential energy surfaces in both S₀ and S₁ states were scanned with varying O-H bond lengths. The results of potential energy surface analysis adequately proved that the HYDRAVH₂ can undergo the ESDPT process in the S₁ state and the double proton transfer process is a stepwise proton transfer mechanism. Our work can pave the way towards the design and synthesis of new molecules.     

EAST装置上W波段多道极向相关反射仪的研制

在EAST装置上安装了X模极化W波段多道相关反射仪，用于测量等离子体芯部密度涨落。该诊断利用低损耗(<3dB)多工器将4个不同频率(79.2GHz，85.2GHz，91.8GHz和96GHz)的微波耦合在一起，通过同一个天线发射。反射波由两个极向分离(~5cm)的天线接收，通过下变频技术实现外差测量。通过对两个极向天线接收的信号进行相关分析，获得芯部湍流垂直速度。对2018年低约束模式(L模)放电进行分析发现，在电子回旋共振加热(ECRH)等离子体中，芯部湍流垂直速度在电子逆磁漂移方向。而在注入同向中性束(co-NBI)后，芯部湍流垂直速度变为离子逆磁漂移方向。     

Fission Barrier for ^240Pu in the Quadrupole Constrained Relativistic Mean Field Approach

The fission barrier for ^240pu is investigated beyond the second saddle point in the potentiM energy surface by the constrained relativistic mean field method with the newly proposed parameter set PK1. The microscopic correction for the centre-of-mass motion is essentiM to provide the correct potential energy surface. The shell effects that stabilize the nuclei against the fission is also investigated by the Strutinsky method. The shapes for the ground state, fission isomer and saddle-points, etc, are studied in detail.     

加热炉热过程动态操作数学模型

根据加热炉生产特点,建立了钢坯加热过程的动态操作数学模型,分析了待轧时间变化时炉内钢坯温度分布情况。并针对加热炉待轧的灰色性,采用多目标灰色局势决策方法,得出了相应合理的待轧优化控制策略。模拟结果表明:该方法具有良好的动态性能,适合于在线控制。     

Spurious Shell Closures in the Relativistic Mean Field Model

Following a previous systematic theoretical study of the ground-state properties of over 7000 nuclei from the proton drip line to the neutron drip line in the relativistic mean field model [Prog. Theor. Phys. 113 （2005） 785], which is in fair agreement with existing experimental data, we observe a few spurious shell closures, i.e. proton shell closures at Z = 58 and Z = 92. These spurious shell closures are found to persist in all the effective forces of the relativistic mean field model, e.g. TMA, NL3, PKDD and DD-ME2.     

甲基丙烯酸全氟烷基代乙酯对天然橡胶乳液辐射改性研究

天然橡胶的性能与其组成中的C C双键有密切关系,由于C C双键的存在,为天然橡胶的改性提供了便利,大多数天然橡胶的改性方法,如氯化、氢氯化、环化、环氧化、接枝共聚等皆是建立在这一思路基础上的.White等[1]认为接枝天然橡胶的目的是提高天然橡胶的机械强度,赋予特殊的功能.作     

刚果红与血清白蛋白相互作用的极谱分析

在pH4．7HAc-NaAc缓冲溶液中，刚果红与蛋白质(BSA或HSA)作用形成络合物，使刚果红-0．35V(vs SCE)的还原峰电流下降，峰电流的降低值同所加的BSA或HSA质量浓度在一定范围内呈线性关系；BSA和HSA的线性范围分别为0．5～12mg／L和0．5～11mg／L，检出限分别为0．25和0．20mg／L；运用该法测定了人血清白蛋白样品，结果令人满意。     

铽与苯乙酮酸、2,2''''-联吡啶、1,10-菲口罗啉、三苯基氧膦铽三元配合物的合成、结构表征及荧光性能的研究

以硝酸铽、苯乙酮酸（HL）, 2, 2＇-联吡啶（dipy）、 1, 10-菲啰啉（phen）和三苯基氧膦（TPPO）合成了TbL3dipy（H2O）2, TbL3phen（H2O）2和TbL2（TPPO）2NO3 3种新型固态配合物. 用元素分析、电导率、红外光谱和核磁共振谱对其进行了表征, 确定了配合物的组成. IR表明, 配合物中羧酸根可能以单齿方式配位. 1HNMR显示, 苯乙酮酸根配位后苯环上5个氢原子的化学位移移向高场. 室温下测定了配合物的荧光激发光谱, TbL3dipy（H2O）2, TbL3phen（H2O）2和TbL2（TPPO）2NO3最佳激发波长分别为361.0, 359.0和367.0 nm;分别以最佳激发波长测定了配合物的发射光谱, 配合物TbL3dipy（H2O）2, TbL3phen（H2O）2 和TbL2（TPPO）2NO3显示Tb3＋离子的特征发射光谱, TbL3dipy（H2O）2和TbL3phen（H2O）2均产生四条谱带, 分别归属于^5D4-^7Fj（j= 6, 5,4,3）能级跃迁（TbL3dipy（H2O）2： 489.0, 545.0, 584.0, 620.0 nm;TbL3phen（H2O）2： 490.0, 544.0, 583.0, 620.0 nm）;但在相同测定条件下, TbL2（TPPO）2NO3仅显示5D4-7F5（544.0 nm）能级跃迁光谱. 3种配合物中TbL3dipy（H2O）2发光强度最高.     

纯水相中微波辐射下铜催化异噻唑啉酮的合成

建立了一种简单实用、经济高效的以取代2-碘苯甲酸、芳胺和无机硫源硫化钾为原料,以廉价氯化铜为催化剂,纯水作为溶剂,100℃条件下串联合成苯并异噻唑啉酮衍生物的微波催化体系,一系列苯并异噻唑啉酮衍生物被较好地合成出来,最高产率达85%。产物结构经~1H NMR、~(13)C NMR及MS得到确证。该方法具有产率高、操作简单、环境友好等优点。     

话说葡萄酒中的抗癌明星——白藜芦醇

白藜芦醇被喻为继紫杉醇之后的又一新的绿色抗癌药物,是备受关注的一种具有重要生理活性的天然物质。主要介绍了其结构、性质、存在、生理功能及生产方法等。