Investigation of single MoFe3S4 cubane cluster: I. First successful synthesis by spontaneous self-assembly reaction and structure of (Et4N) [MoFe3S4(Et2NCSS)5]CH3CN

A single MoFe₃S₄ cubane-like cluster compound has been synthesized through spontaneous self-assembly of simple inorganic salts with organosulfur ligand for the first time. (Et₄N)-(MoFe₃S₄(Et₂NCSS)₅] CH₃CN(1) is quite stable in air. The crystal of 1 is monoclinic with space group P2/c, a=22.897 (3)Å, b= 12.399 (2)Å, c=20.928 (4)Å, β=97.15 (1)°, and Z=4. A full matrix least-squares refinement with 6725 unique reflections for all nonhydrogen atoms gives R=0.068. The anion of 1 is the first isolated single MoFe₃S₄ cubane cluster with core oxidation state [MoFe₃S₄]⁴⁺. The distance between the two 6-coordinate metal atoms (Mo, Fe) is 2.624 Å, which is the shortest M-M' bond observed for Mo-Fe-S clusters so far and the only one shorter than similar distances in FeMo-cofactor. The bond orders of this anion were calculated by EHMO method and the results coincide with the general rule. The structural feature and the unusual stability of 1 can be attributed to the bidentate chelating effect of Et₂NCSS-, which leads to high coordination of metal atoms and the various ligated types.     

基于免疫磁性纳米球快速高效准确检测淋巴结转移癌细胞

发展了一种基于免疫磁性纳米球(IMNs)快速、高效、准确检测淋巴结转移癌细胞(LNMCCs)的策略.首先利用本课题组发展的方法制备了具有磁性和生物靶向双功能的IMNs,然后利用IMNs通过免疫磁分选对淋巴结转移癌病人淋巴结穿刺物中的LNMCCs进行分离和富集,最后采用瑞氏染色法和免疫细胞化学(ICC)对富集的LNMCCs进行鉴定,实现对LNMCCs的快速高效准确检测.免疫磁分选实现了LNMCCs的分离和富集,可以有效降低淋巴结穿刺物中的背景干扰;瑞氏染色法和ICC鉴定为准确诊断提供了更多可靠依据,因此,传统细胞学敏感性、特异性和诊断准确率不高的问题得到明显改善.其次,淋巴结穿刺物与IMNs的孵育只需5 min,简便快速,完整保留了LNMCCs的形态学特征,为淋巴结转移癌(LNMC)的分类和后续病理学分析提供了重要基础.此外,IMNs对淋巴结穿刺物中上皮来源癌细胞的特异性捕获可以确诊捕获的细胞为LNMCCs,实现了LNMC和恶性淋巴瘤的鉴别诊断.最后,采用本方法检测了110例病人淋巴结穿刺物中的LNMCCs,总诊断准确率高达98.2%,特异性为100.0%,敏感性为98.0%,相比于传统细胞学诊断都有明显的提高.因此,IMNs用于LNMC病人淋巴结穿刺物中LNMCCs的检测是一次新的尝试,为LNMC的诊断和研究提供了新思路.     

Synthesis and characterization of polymer eight-coordinate (enH2)[YIII(pdta)(H2O)](2)·10H2O as well as the interaction of [YIII(pdta)(H2O)]2(2-) with BSA

The eight-coordinate (enH2)[YIII(pdta)(H2O)](2)·10H2O (en=ethylenediamine and H4pdta=1,3-propylenediamine-N,N,N',N'-tetraacetic acid) was synthesized, meanwhile its molecular and crystal structures were determined by single-crystal X-ray diffraction technology. The interaction between [Y(III)(pdta)(H2O)]2(2-) and bovine serum albumin (BSA) was investigated by UV-vis and fluorescence spectra. The results indicate that [YIII(pdta)(H2O)]2(2-) quenched effectively the intrinsic fluorescence of BSA via a static quenching process with the binding constant (Ka) of the order of 10(4). Meanwhile, the binding and damaging sites to BSA molecules were also estimated by synchronous fluorescence. Results indicate that the hydrophobic environments around Trp and Tyr residues were all slightly changed. The thermodynamic parameters (ΔG=-25.20 kJ mol(-1), ΔH=-26.57 kJ mol(-1) and ΔS=-4.58 J mol(-1) K(-1)) showed that the reaction was spontaneous and exothermic. What is more, both ΔH and ΔS were negative values indicated that hydrogen bond and Van der Waals forces were the predominant intermolecular forces between [YIII(pdta)(H2O)]2(2-) and BSA.     

高效阴离子交换色谱-铜/铂修饰电极安培法测定大观霉素

采用阴离子交换色谱分离,在CuSO4溶液中加入少量镧系化合物,经电沉积制备La3+-Cu/pt/CME工作电极,建立了直流安培电化学法(DC)直接检测硫酸大观霉素的方法。考察了流动相浓度、测定电位等参数对色谱分离和测定的影响。在固定相为CarboPac PA10阴离子交换柱、流动相为26mmol/L NaOH,流速为0.6mL/min的色谱条件下,检测电位为0.68V时,硫酸大观霉素峰面积与其浓度在0.12～12mg/L(r=0.9991)和12～280mg/L(r=0.9995)两个范围内呈线性。本方法不需要柱前和柱后衍生化,能同时测定硫酸大观霉素中的主要组分和杂质。修饰电极制作方法简单,催化稳定性好,可作为电化学传感器测定硫酸大观霉素中的各组分。     

CdS量子点敏化ZnO纳米棒阵列电极的制备和光电化学性能

采用连续式离子层吸附与反应法制备了CdS量子点敏化的ZnO纳米棒电极.应用扫描电子显微镜(SEM)、X射线衍射(XRD)和透射电子显微镜(TEM)对CdS量子点/ZnO纳米棒电极的形貌、晶型和颗粒尺寸进行了分析和表征;采用光电流-电位曲线和光电流谱研究了不同CdS循环沉积次数及不同沉积浓度对复合电极的光电性能影响.结果表明,前驱体浓度都为0.1mol·L-1且沉积15次敏化后的ZnO纳米棒阵列电极光电性能最好.与单纯的ZnO纳米棒阵列电极和单纯的CdS量子点电极相比,其光电转换效率显著提高,单色光光子-电流转换效率(IPCE)在380nm处达到76%.这是因为CdS量子点可以拓宽光的吸收到可见光区,并且在所形成的界面上光生载流子更容易分离.荧光光谱实验进一步说明了光电增强的原因是,两者间形成的界面中表面态大大减少,有利于减少光生电子和空穴的复合.     

Spectroscopic Investigation on the Synergistic Effects of Ultrasound and Dioxopromethazine Hydrochloride on Protein

The bovine serum albumin (BSA) was selected as a target molecule, the sonodynamic damage to protein in the presence of dioxopromethazine hydrochloride (DPZ) and its mechanism were studied by means of absorption and fluorescence spectra. The results of hyperchromic effect of absorption spectra and quenching of intrinsic fluorescence spectra indicated that the synergistic effects of ultrasound and DPZ could induce the damage of BSA molecules. The damage degree of BSA molecules increased with the increase of ultrasonic irradiation time and DPZ concentration. The results of synchronous fluorescence and three-dimensional fluorescence spectra further confirmed that the synergistic effects of ultrasound and DPZ induced the damage of BSA molecules. The results of oxidation-extraction photometry with several reactive oxygen species (ROS) scavengers indicated that the damage of BSA molecules could be mainly due to the generation of ROS, in which both ¹O₂ and ·OH were the important mediators of the ultrasound-inducing BSA molecules damage in the presence of DPZ.     

1,3-双(1-苯基-1H-四唑-5-巯基)-乙酰苯腙钳形受体对卤素阴离子的识别机理

采用密度泛函B3LYP(Becke, three-parameter, Lee-Yang-Parr)和HF(Hatree-Fock)方法, 从理论上探讨了1,3-双(1-苯基-1H-四唑-5-巯基)-乙酰苯腙(DAPHZ)钳形受体对卤素阴离子的识别机理,结果发现DAPHZ受体以其钳形结构中的-N-H基团与卤素阴离子间形成双侧红移氢键进行识别. 经BSSE校正后DAPHZ•••F-, DAPHZ•••Cl-和DAPHZ•••Br-体系的分子识别相互作用能ΔECP分别为-327.5,-163.5和-148.3 kJmol-1, 说明钳形DAPHZ受体对F-具有最好的识别能力. 此外, 采用自然键轨道(NBO)计算, 相关H原子化学位移计算及分子中原子(AIM)等理论分析了识别体系中红移氢键的电子结构和性质, 结果表明APHZ受体对卤素阴离子的识别能力的相对顺序为DAPHZ•••F- >> DAPHZ•••Cl- ≈ DAPHZ•••Br-.     

ATR-FTIR研究超支化聚酯对PEG型聚氨酯弹性体的力学性能及形态的影响

为改善聚乙二醇(PEG)型聚氨酯弹性体的力学性能,将改性超支化聚酯(HBP)引入形成共混体系,利用衰减全反射傅里叶变换红外光谱(ATR-FTIR)研究了聚氨酯胶片的化学结构.结果表明,超支化聚酯对PEG型聚氨酯弹性体具有较好的增强增韧作用,当加入0.4%的第三代超支化聚酯时,聚氨酯弹性体的拉伸强度比空白胶片提高了2.5...     

Ballistic phonon transport through a Fibonacci array of acoustic nanocavities in a narrow constriction

We investigate the ballistic phonon transport through a Fibonacci array of acoustic nanocavities in a narrow constriction of a semiconductor nanowire at low temperatures. It is found that the transmission spectrum of such a system consists of quasiband gaps and narrow resonances caused by the coupling of phonon waves. Both phonon transmission and thermal conductance exhibit the similarity due to the Fibonacci sequence structure. The similarity is sensitive to the number n and parameters of nanocavities. The results are compared with those in a periodic acoustic nanocavities.     

基于新型螺氧杂蒽主体的高效蓝色磷光有机发光二极管

We synthesized a series of novel spiro[fluorene-9, 9'-xanthene] (SFX)-based host materials via a one-step palladium-catalyzed cross-coupling reaction. These materials have high triple energy levels and high yield, and thus can be used as hosts for blue phosphors. Blue phosphorescent organic light-emitting devices (PHOLEDs) with a bis (3, 5-difluoro-2-(2-pyridyl) phenyl-(2-carboxypyri-dyl) iridium (Ⅲ) (FIrpic) emission were fabricated. Furthermore, we applied cohosts composed of one of the new synthesized materials and the hole transport material di-[4-(N, N-ditolyl-amino)-phenyl]cyclohexane (TAPC) to the blue PHOLEDs to successfully acquire efficient blue emissions. The SFX-based material provided efficient energy transfer while TAPC improved the mobility of the cohost as well as reduced the working voltage. Maximum current efficiencies of 22.56 and 25.93 cd·A^-1 and the maximum brightnesses of 6421 and 6196 cd·m^-2 were obtained for the PHOLEDs with TAPC: 2-(9-phenyl-fluoren-9-yl) spiro[fluorene-9, 9'-xanthene] (PF-SFX) and TAPC: 2-(9-(4-(octyloxy)-phenyl)-9H-fluoren-9-yl) spiro[fluorene-9, 9'-xanthene] (C8OPF-SFX) cohosts, respectively. The experimental results obtained for the four SFX-based host materials were enough to declare that SFX is an effective main unit that can be used to build efficient host materials for blue phosphors containing only C, H, and O basic elements.