Sr3Al2O6:Eu2+红色发光纳米晶的新型形貌与发光性能的研究

对于稀土发光纳米晶来讲,产品颗粒尺寸与形貌不仅对发光性能有影响,而且直接影响其应用[1,2].如颗粒尺寸在1～10 μm之间且形貌接近于球形的发光微米晶在涂屏时发光效率是最高的,而具有新型微观结构与形貌的稀土发光纳米晶,如纳米线、纳米棒及具有自组装特性的花晶等纳米结构材料由于在纳米发光器件方面有着潜在的应用价值,已成为当今纳米科学的研究焦点.     

高频介质系统介电性能与相组成的定量关系分析

采用普通电子陶瓷工艺制备两种高频介质系统ZnO-B2O3-SiO2三元系和BaO-PbO-Nd2O3-Bi2O3-TiO2五元系,通过XRD分析确定各系统的主晶相, 运用衍射峰强度计算法准确测定出各组分的体积百分含量,并代入Lichnetecker对数混合定则,计算出系统的介电性能,获得了分析介质系统介电性能与物相含量之间定量关系的新方法.     

Four New Gallate Derivatives from Wine-Processed Corni Fructus and Their Anti-Inflammatory Activities

Four new gallate derivatives—ornusgallate A, ent-cornusgallate A, cornusgallate B and C (1a, 1b, 2, 3)—were isolated from the wine-processed fruit of Cornus officinalis. Among them, 1a and 1b are new natural compounds with novel skeletons. Their chemical structures were elucidated by comprehensive spectroscopy methods including NMR, IR, HRESIMS, UV, ECD spectra and single-crystal X-ray diffraction analysis. The in vitro anti-inflammatory activities of all compounds were assayed in RAW 264.7 cells by assessing LPS-induced NO production. As the result, all compounds exhibited anti-inflammatory activities at attested concentrations. Among the tested compounds, compound 2 exhibited the strongest anti- inflammatory activity.     

A Chinese Lantern-like 2D Cu(Ⅱ) Coordination Polymer Constructed by Bis-imidazole and Dicarboxylate Co-ligands: Synthesis,Crystal Structure and Photocatalytic Activity

A new Cu(II) coordination polymer, {[Cu(1,3-BIP)(TFBDC)]·DMF}n(1,1,3-BIP is a 1,3-bis(imidazole)propane, and H2TFBDC is 2,3,5,6-tetrafluoroterephthalic acid) was prepared under solvothermal conditions and characterized by single-crystal and powder X-ray diffraction, IR spectra, thermogravimetric analyses and elemental analyses. The single-crystal X-ray diffraction reveals that metal coordination polymer 1(MCP 1) shows a two-dimensional sheet layer structure, which is further reinforced through strong intermolecular hydrogen bonding to form a 3 D supramolecular framework. Furthermore, the photocatalytic experiment result indicates the degradation ratios of methyl orange(MO) reach 83.4% within 180 minutes when MCP 1 acts as catalyst.     

双波长分光光度法测定河北省多种粮豆作物中直、支链淀粉含量

本文采用双波长分光光度法对河北省不同地区多种粮食豆作物中直,支链淀粉的含量进行了测定,并探讨了杂粮中不同淀粉含量与糖尿病食疗的关系。     

Theoretical Study on the Reaction of FeS+(6∑+,4Ф)with COS in the Gas Phase

The possible reaction mechanisms of FeST(6∑+and 4Ф states)with COS in the gas phase have been studied by using density functional theory at the B3LYP/TZVP and B3LYP/6-311+G*levels:the O/S exchange reaction(FeS++COS=FeO++CS2),O-transfer reaction(FeS++COS=FeSO++CS)and S-transfer reaction(FeS++COS=FeS2++CO).The calculation results show that the large barriers(205.7 and 310.1 kJ/mol)and the small probability of forming the preceding intermediate indicate a much lower efficiency of the O/S exchange and the O-transfer reactions and their corresponding products may not be observed experimentally.FeS2+,the product of S-transfer reaction,is predicted to be the main product.But the reactivity of the 6∑+ground state of FeS+toward COS is lower than the earlier transition metal sulfide cations MS+(M=Sc,Ti and V),although it has more reaction channels and different mechanisms.     

未来十年纳米光子学若干重点发展领域

纳米光子学已经对人们的日常生活产生了重要影响,并且纳米光子学器件产品有强大的市场需求,因此其研究结果可以很快转化为商品。文章介绍了在未来5到10年内对光子工业有重大影响并且有望进入商品市场的11个纳米光子学领域,其中包括:纳米尺度量子光子学、全光路由、用于增强磁存储的表面等离子体光子学、用于诊断治疗和药物输送纳米光子学、纳米成像、分子尺度上的化学与生物传感器、纳米标签、纳米尺度上操控光场的分布(光伏器件和LED/OLED)、原型试制的新技术、量身定制光学特性的纳米光子材料以及太赫兹技术等,希望文章能对中国的纳米光子学研究及其工业化应用有一定帮助。     

Theoretical study on the reaction of the Δ ground state of ZrO with CS2 in the gas phase

The mechanisms for the three products ZrS⁺, and ZrOS⁺ of the title reaction have been studied by using B3LYP/6-311+G* and CCSD(T)/SDD+6-311+G* methods. It is found that both ZrS⁺ and formations involve the same O/S exchange process via a four-center transition state TS12 to form an intermediate IM2. Exception of that IM2 can dissociate into the ZrS⁺ product, a favorable intramolecular rearrangement mechanism associated with the formation has been identified, which explains why ZrS⁺ was excluded as a precusor for the formation and why the lower efficiency of the ZrS⁺ formation was observed in experiment. For the formation of ZrOS⁺, two parallel channels (path A and B) yielding their corresponding product isomer have been identified. Path B involving an insertion–elimination mechanism with a calculated barrier underestimated by ca. 25.0 kJ/mol should be attributed to the threshold of 114.8 ± 12.5 kJ/mol assigned in the experiment. But path A should make some contributions to the formation of ZrOS⁺ at elevated energy.     

铱配合物在磷光化学传感器中的应用

由于在生物领域和物联网领域的广泛应用,化学传感器在近期发展迅速.相比于纯有机分子的荧光化学传感器,基于重金属配合物的磷光化学传感器由于发光寿命长,斯托克斯位移大等优点越来越引起人们的广泛关注.重金属铱配合物三线态寿命短,发光效率高而且配合物的发射波长容易受配体的改变而发生变化,因此成为最好的磷光传感器材料之一.本文介绍了铱配合物在磷光化学传感器领域中的应用,具体包括:阳离子传感器、阴离子传感器、氧分子传感器、氨基酸传感器、pH传感器等,并指出了相比于其它磷光化学传感器,基于铱配合物的磷光化学传感器的优势以及目前所存在的问题,最后,对基于铱配合物的磷光化学传感器的研究和发展方向进行了展望.     

C2H3与CH3F氢抽提反应机理与动力学性质

采用双水平直接动力学方法对C₂H₃与CH₃F氢抽提反应进行了研究. 在QCISD(T)/6-311++G(d, p)//B3LYP/6-311G(d, p)水平上, 计算的三个反应通道R1、R2和R3的能垒(ΔE^≠)分别为43.2、43.9和44.1 kJ·mol^-1, 反应热为-38.2 kJ·mol^-1. 此外, 利用传统过渡态理论(TST)、正则变分过渡态理论(CVT)和包含小曲率隧道效应(SCT)的CVT, 分别计算了200-3000 K温度范围内反应的速率常数k^TST、k^CVT和k^CVT/SCT. 结果表明: (1) 三个氢抽提反应通道的速率常数随温度的增加而增大, 其中变分效应的影响可以忽略, 隧道效应则在低温段影响显著; (2) R1反应是主反应通道, 但随着温度的升高, R2反应的竞争力增大, 而R3反应对总速率常数的影响很小.