两个4-连接配位网络的锌(Ⅱ)配位聚合物的合成、结构和荧光性质

以5-氨基四氮唑(HATz),异烟酸(HPyc)和ZnSO4·7H2O或Zn(NO3)2·6H2O为反应物,在DMF溶剂热条件下分别得到了2个锌(Ⅱ)配位聚合物{[(CH3)2NH2]·[Zn(ATz)(SO4)]}n(1)和{[Zn(ATz)(Pyc)]·0.5DMF}n(2),并对它们的组成和结构进行了表征。配合物1是由4-连接(4,4)网络拓扑的[Zn(ATz)(SO4)]nn-二维阴离子层和[(CH3)2NH2]+阳离子间通过氢键作用形成的二维波浪层结构。配合物2则是1个二重穿插的4-连接金刚烷拓扑的三维微孔金属-有机框架结构,客体DMF分子填充在孔道内。室温下的固体荧光实验表明,在350 nm的光激发下,配合物1和2分别在为445 nm和458 nm处出现强烈的荧光发射。     

基于N-((3-吡啶基)磺酰基)天冬氨酸的Co(Ⅱ)、Zn(Ⅱ)、Cd(Ⅱ)配位聚合物的合成、磁性和荧光性质

以N-((3-吡啶基)磺酰基)天冬氨酸(H₂L)为配体,采取水热合成的方法,合成了配位聚合物[M(HL)₂]_n(M=Co,1;Zn,2;Cd,3)。X射线单晶衍射分析表明,它们的晶体同构。1的磁性分析表明,1的Curie常数为4.66cm³·mol^-1·K,Curie-Weiss常数为-21.23K;与配体H₂L相比,2和3的发射光谱发生了明显的蓝移,可能归因于配体到金属的电荷转移。     

Ionic liquid-modified magnetic polymeric microspheres as dispersive solid phase extraction adsorbent: a separation strategy applied to the screening of sulfamonomethoxine and sulfachloropyrazine from urine

Ionic liquid-modified magnetic polymeric microspheres (ILMPM) were prepared based on Fe₃O₄ magnetic nanoparticles (MNPs) and ionic liquids (ILs) incorporated into a polymer. The composites were characterized using scanning electron microscopy, Fourier transform infrared analysis, thermogravimetric analysis, X-ray diffraction, and vibrating magnetometer, which indicated that ILMPM had a regularly spherical shape and strong magnetic property. The obtained ILMPM were successfully applied as a special adsorbent of magnetic dispersive solid phase extraction (MDSPE) for the rapid extraction and isolation of sulfamonomethoxine sodium and sulfachloropyrazine sodium in urine. The factors that affected extraction efficiency, such as adsorption conditions, desorption conditions, washing and elution solvents, and pH of the sample solution, were optimized. Under the optimum condition, good linearity in the range of 0.005–2.0 μg g^?1 (r?≥?0.9996) was obtained for the two sulfonamides (SAs); the average recoveries at three spiked levels ranged from 86.9 to 102.1 %, with relative standard deviations of ≤4.3 %. The presented ILMPM-MDSPE method combined the advantages of ILs, MNPs, and MDSPE and therefore could be potentially applied for rapid screening of SAs in urine.     

Selective adsorption and stable solidification of radioactive cesium ions by porous silica gels loaded with insoluble ferrocyanides

Development of highly functional cesium selective adsorbents for the decontamination of high-activity-level water(HALW) from the Fukushima NPP-1 accident is very urgent. In order to selectively adsorb the radioactive cesium, three kinds of novel porous silica gels loaded with insoluble ferrocyanides(SLFC) were prepared using a successive impregnation/precipitation method. Based on the results of previous research, the SLFC composites have relatively large uptake ratio above 95%, distribution coefficients(Kd) above 103 cm3/g, and excellent adsorption kinetics even in seawater. The solidification results also indicate that zeolites have an excellent Cs immobilization characteristic, gas-trapping and self-sintering abilities, and low leachability. We chose three kinds of SLFC composites to achieve the optimization of solidification by mixing with nine kinds of additives at high temperatures(up to 1200 °C). The Cs contents in the three composites were estimated to be below 30% of the initial contents and decreased with the three stages at calcination temperatures ranging from 25 to 1200 °C. By contrast, the Cs immobilization ratio was markedly lowered by mixing with additives: of those, allophane had the best immobilization result. By increasing the additive ratio to 50 wt%, the Cs immobilization ratio became almost 100% and no volatilization of Cs was detected even after calcination at 1200 °C. This result indicates that calcination of the mixture of SLFC composites after adsorbing Cs+ ions and specific additives under appropriate ratio is effective for stable solidification.     

铁基分子筛活性位点的制备控制及对NH3-SCR活性的影响

采用离子交换法,通过不同制备条件制备Fe-beta分子筛,并探讨不同制备条件对催化剂活性位点和NH3-SCR活性的影响。通过UV-Vis分析,将不同位置的吸收峰归属于不同的铁活性位点,300nm以下的高能谱区可以归属于孤立的Fe3+位点,300nm-400nm间归属于低聚的FexOy簇,而400nm以上为Fe2O3大颗粒聚合物。对比不同催化剂的SCR活性发现,孤立的Fe3+和低聚态的Fe3+是主要的活性位点,这两种物种的所占比例高低直接影响了催化剂的活性。而大尺度的Fe2O3为非活性位点,因尽量控制并降低其所占比例。另外低聚态的Fe3+所占比例越高,N2O的生成量越高,N2的选择性越差。因此,在制备过程中,除了控制大尺度的Fe2O3的含量,同时要尽量降低低聚态的Fe3+的含量,以增加N2的选择性。采用离子交换法制备Fe-beta催化剂,pH、交换温度、前驱体种类、硅铝比、煅烧条件等制备条件会对Fe-beta的活性位点造成影响,从而导致活性差异。根据实际应用需求,调控制备条件,可有效控制活性物种的分布,制备具有高效NH3-SCR活性的铁基分子筛催化剂。     

Optimizing the Photovoltaic Performance of Organic Solar Cells for Indoor Light Harvesting

Organic solar cells (OSCs) harvesting indoor light are highly promising for emerging technologies, such as internet of things. Herein, the photovoltaic performance of PTB7-Th:PC₇₁BM solar cells constructed using “optimized (with 1,8-diiodooctane (DIO))” and “non-optimized (without DIO)” processing conditions are compared for indoor and outdoor applications. We find that in comparison to the “optimized” solar cell, the “non-optimized” solar cell is less efficient under simulated solar light illumination (100 mW cm⁻², spectral range 350–1100 nm), owing to significant bimolecular charge carrier recombination losses. However, under simulated indoor illumination (3.28 mW cm⁻², spectral range 400–700 nm), bimolecular recombination losses are effective suppressed, thus the power conversion efficiency of the solar cell without DIO was increased to 14.7 %, higher than that of the solar cell with DIO (14.2 %). These results suggest that the common strategy used to optimize the OSCs could be undesired for indoor OSCs. We demonstrate that the efforts for realizing the desired “morphology” of the active layer for the outdoor OSCs may be unnecessary for indoor OSCs, allowing us to realize high-efficiency indoor OSCs using a non-halogenated solvent.     

18F标记吲哚苯醌衍生物分子探针的合成及正电子发射型计算机断层显像

基于2-苯基萘型结构,以2-甲基吲哚和四氯苯醌、1-二甲基胺-2-丙炔和碘甲基硼酸频哪醇酯分别作为起始底物,经5步反应合成了一种吲哚苯醌类分子探针的前体。其结构经¹H NMR, ¹³C NMR和HR-MS(ESI)表征。对该前体进行放射性标记,再经高效液相色谱分析纯化,最后将探针注入小鼠体内进行正电子发射型计算机断层显像（PET）。结果表明：探针分子进入小鼠体内后,在膀胱、胆和肠道聚集,随后经肠道和膀胱代谢排出体外。     

微波消解-电感耦合等离子体质谱(ICP-MS)法测定板栗中的矿物元素及稀土元素

为了准确测定板栗中矿物元素和稀土元素的含量水平,采用冷冻干燥方式预处理样品,选用硝酸和过氧化氢体系微波消解样品,结合电感耦合等离子体质谱技术,建立了板栗中钠(Na)、钾(K)、镁(Mg)、锰(Mn)、铁(Fe)、钒(V)、钴(Co)等19种矿物元素及镧(La)、铈(Ce)、镨(Pr)、钕(Nd)、钐(Sm)、铕(Eu)、钆(Gd)、铽(Tb)、镝(Dy)、钬(Ho)、铒(Er)、铥(Tm)、镱(Yb)、镥(Lu)、钇(Y)等15种稀土元素的同时分析测定方法。方法检出限为0.0027~0.78μg/L,相对标准偏差为1.4%~6.3%。通过国家标准物质GBW10019苹果的准确度实验验证,测定结果均在标准证书值范围内。实验结果表明,方法适用于板栗中矿物元素及稀土元素的同时测定。     

Kinetics of glass transition,crystallization and soft magnetic properties of the Fe76.5Nb3B20Cu0.5 glassy alloys

Journal of Thermal Analysis and Calorimetry - Differential scanning calorimetry was used to investigate the non-isothermal crystallization kinetics of the Fe76.5Nb3B20Cu0.5 glassy alloys. The...     

物理化学教学中安全工程教育的融合与内化实例*

如何强化安全工程教育是化学化工类专业高等教育的一个重要课题。通过对蒸汽锅炉爆炸、火灾爆燃事故以及锈蚀危害等3个实例的详细讲述,指出在物理化学的教学中,若适时融入相关的安全工程教育,可以使学生深刻理解安全事故发生及防范所依赖的物理化学原理,从而起到安全意识的内化作用。教学中现代教育技术的引入可以增强这一效果。