Design Strategies for High-Performance Aqueous Zn/Organic Batteries

Organic electroactive compounds are attractive to serve as the cathode materials of aqueous zinc-ion batteries (ZIBs) because of their resource renewability, environmentally friendliness and structural diversity. Up to now, various organic electrode materials have been developed and different redox mechanisms are observed in aqueous Zn/organic battery systems. In this Minireview, we present the recent developments in the energy storage mechanisms and design of the organic electrode materials of aqueous ZIBs, including carbonyl compounds, imine compounds, conductive polymers, nitronyl nitroxides, organosulfur polymers and triphenylamine derivatives. Furthermore, we highlight the design strategies to improve their electrochemical performance in the aspects of specific capacity, output voltage, cycle life and rate capability. Finally, we discuss the challenges and future perspectives of aqueous Zn/organic batteries.     

C.I.颜料红177中间体的制备工艺改进

本文较为系统地研究了铜粉催化剂加入方式对C.I.颜料红177中间体4,4'-二氨基-1,1'-二蒽醌-3,3'-二磺酸(DAS)合成过程中的乌尔曼偶联反应速率的影响规律。 研究结果表明,在55 ℃较佳反应温度下,先加入与溴氨酸钠质量比为2:5的铜粉,反应一段时间后再加入与溴氨酸钠的质量比为1:5的铜粉,与一次性加入与溴氨酸钠的质量比为3:5的铜粉相比较,综合反应时间可节省2~3 h。 另外,对于DAS中混有的铜盐,采取在制备过程中加入柠檬酸的方法予以去除,此举可提高DAS的纯度。 当铜粉与柠檬酸的质量比为6:1时,可使DAS中铜盐的含量小于0.001%。 此外还探究了蒸馏后滤液的剩余量对DAS收率的影响,结果表明,滤液的剩余量在20 mL时,DAS的收率在95%以上。 基于本文的研究结果提出,欲进一步提高该反应的收率,需要寻找更高效的催化剂。     

基于手机光线传感器为检测器的简易光度计的自组装设计

By using light sensors of the cellphone, we build a simple photometer which can be used in quantitative analysis experiments. We have performed 5 replicate measurements of iron with phenanthroline to verify reproducibility and stability. We find the absorbance of the sample has a good linear relationship with the concentrations of iron with a R² value around 0.999 and the RSD of 2.81%. The result is 4.94 μg·mL^-1 with spectrophotometer and 5.11 μg·mL^-1 with our photometer. The photometer is simple, convenient, accurate and realistic by using a phone as detector, which can replace the traditional spectrophotometer in the laboratory class. The students can enhance their understanding of the structure and principle of spectrophotometer by the DIY photometer experiment.     

Fabrication of Predominantly Mn4+‐Doped TiO2 Nanoparticles under Equilibrium Conditions and Their Application as Visible‐Light Photocatalyts

The chemical state of a transition‐metal dopant in TiO₂ can intrinsically determine the performance of the doped material in applications such as photocatalysis and photovoltaics. In this study, manganese‐doped TiO₂ is fabricated by a near‐equilibrium process, in which the TiO₂ precursor powder precipitates from a hydrothermally obtained transparent mother solution. The doping level and subsequent thermal treatment influence the morphology and crystallization of the TiO₂ samples. FTIR spectroscopy and X‐ray photoelectron spectroscopy analyses indicate that the manganese dopant is substitutionally incorporated by replacing Ti⁴⁺ cations. The absorption band edge can be gradually shifted to 1.8 eV by increasing the nominal manganese content to 10 at %. Manganese atoms doped into the titanium lattice are associated with the dominant 4+ valence oxidation state, which introduces two curved, intermediate bands within the band gap and results in a significant enhancement in photoabsorption and the quantity of photogenerated hydroxyl radicals. Additionally, the high photocatalytic performance of manganese‐doped TiO₂ is also attributed to the low oxygen content, owing to the equilibrium fabrication conditions. This work provides an important strategy to control the chemical and defect states of dopants by using an equilibrium fabrication process.     

Comprehensive identification of the binding sites of cisplatin in hen egg white lysozyme

Platinum drugs have become one of the most important kinds of chemotherapy agents, and the interactions of these drugs with proteins play very important roles in their side effects and drug resistance. However, it is still a challenge to determine the binding sites of platinum drugs in proteins with multiple disulfide bonds and stable three-dimensional structures using mass spectrometry. Here, the interaction between cisplatin and hen egg white lysozyme (HEWL), a multi-disulfide-bond-containing protein with a stable three-dimensional structure, was investigated using Fourier transform ion cyclotron resonance mass spectrometry. Typical disulfide bond reduction with dithiothreitol/tris(2-carboxyethyl)phosphine before trypsin digestion destroyed the binding of cisplatin to HEWL, and no platination sites were found. Efficient trypsin digestion methods for HEWL–cisplatin adducts were developed to avoid the loss of platinum binding to protein. At 55 °C, platinated HEWL was digested directly by trypsin in 6 h, and multiple platinated peptides were observed. In 60 % acetonitrile, the digestion time of platinated HEWL was shortened to 2 h, and most of the platinated peptides were observed. In addition, the reduction of the disulfide bonds of HEWL greatly accelerated the reaction between HEWL and cisplatin, and the potential binding sites of cisplatin in reduced HEWL could be easily recognized. On the basis of the above-mentioned methods, multiple binding sites of cisplatin in HEWL were first identified by mass spectrometry.

CuInS2纳米纸阵列薄膜的制备及生长机理

采用溶剂热合成技术,以氯化铜、硝酸铟和硫脲为反应物,十六烷基三甲基溴化铵(CTAB)为阳离子表面活性剂,草酸为还原剂,无水乙醇为溶剂,直接在掺氟的SnO2透明导电玻璃(FTO)衬底上合成CuInS2(CIS)薄膜.采用扫描电子显微镜(SEM)、高分辨率透射电子显微镜(HRTEM)、X射线衍射(XRD)、拉曼光谱、能量色散谱(EDS)、紫外-可见(UV-Vis)反射光谱和透射光谱对样品的形貌、结构、成分和光学性能进行分析.结果表明,在适当的反应物浓度下,在FTO衬底上形成了垂直衬底生长的、具有良好结晶性能的黄铜矿结构的CIS纳米纸阵列薄膜.CIS薄膜中Cu,In,S的原子比为1.1∶1∶2.09,在紫外-可见和近红外波段具有良好的光吸收特性,禁带宽度约1.51 eV.结合不同反应时间制备的CIS薄膜的形貌、结构和成分分析,讨论了CIS纳米纸阵列薄膜的生长机理.     

黄油中8种类固醇激素的液相色谱/串联质谱检测

建立了黄油中雌酮、α-雌二醇、β-雌二醇、雌三醇、睾酮、表睾酮、孕酮和丙酸睾酮8种类固醇激素的凝胶渗透色谱(GPC)-液相色谱/串联质谱(LC-MS/MS)检测方法。样品用乙酸乙酯-环己烷(1∶1,V/V)提取,提取液经GPC柱净化除脂,GPC浓缩液采用C18色谱柱(100 mm×2.0 mm i.d.,3.0μm)分离,以乙腈和水为流动相进行梯度洗脱,电喷雾电离多反应监测模式进行定性和定量分析。8种类固醇激素以基质匹配外标法定量,药物在1.0~20.0μg/kg线性范围内相关系数(r)均大于0.999;方法检出限(S/N=3)为0.04~0.30μg/kg,定量限LOQs(S/N=10)为1.0μg/kg;添加水平为1.0,2.0,4.0μg/kg时,回收率范围在64.1%~110%之间;相对标准偏差(RSD)小于11%。结果表明,本方法准确、可靠,满足黄油中8种类固醇激素的检测分析要求。     

油脂类食品中脂肪酸单氯丙醇单酯和双酯的分离测定

建立了食品中脂肪酸单氯丙醇单酯与双酯含量的测定方法。称取0.1 g的油脂样品,加入内标后,转入氨基固相萃取柱,先以6.0 mL正己烷洗脱脂肪酸单氯丙醇双酯(MCPD双酯),再以6.0 mL正己烷-乙酸乙酯混合溶剂洗脱脂肪酸单氯丙醇单酯(MCPD单酯),分别收集洗脱液并浓缩至近干,残余物经甲醇钠水解和苯基硼酸(PBA)衍生后,供气相色谱/质谱(GC-MS)分析。MCPD单酯、MCPD双酯的检出限在83~142μg/kg(均以MCPD计)之间,线性范围为25~500μg/L(R2>0.9990)。以花生油和婴幼儿奶粉脂肪提取物为基质,在250~1000μg/kg范围内进行3种浓度水平的加标回收实验,MCPD单酯与双酯的回收率在86.5%~104.0%之间,相对标准偏差(RSD)为2.4%~13.2%(n=6)。此外,本方法成功应用于市售食用植物油和婴幼儿奶粉中MCPD单、双酯的污染调查。     

Fabrication of free-standing multilayer films by using pH-responsive microgels as sacrificial layers

A facile way to prepare free-standing polyelectrolyte multilayer films of poly(sodium 4-styrenesulfonate)(PSS)/poly(diallyldimethylammonium)(PDDA) was developed by applying a new pH-dependent sacrificial system based on cross-linked poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) microgels. The tertiary amine groups of PDMAEMA microgels can be protonated in acidic environment, and the protonated microgels were deposited by layer-by-layer (LbL) technique with PSS. PSS/PDDA multilayer films were constructed on the top of the PSS/microgels sacrificial layers. The LbL assembly process was investigated by UV–vis spectroscopy. Further study shows that the free-standing PSS/PDDA multilayer films can be obtained within 3 min by treating the as-prepared films in alkali aqueous solution with a pH of 12.0. The pH-triggered exfoliation of PSS/PDDA multilayer films provides a simple and facile way to prepare LbL assembled free-standing multilayer films.     

最优折衷三元相位振幅滤波器设计

 为了使在空间光调制器上易于实现的三元相位振幅滤波器在畸变容限、噪声抑制能力和相关峰尖锐度这3个指标上均能取得较好的性能,在最优折衷最大相关高度滤波器的基础上提出了最优折衷三元相位振幅滤波器,并研究了其设计方法。它只需最大化单个准则就能确定最优的临界线角度和支撑区域,简化了优化设计过程。实验结果表明：与二元纯相位滤波器相比,这种滤波器对于在30°的旋转畸变范围内并存在复杂背景的目标能给出更尖锐的相关峰。这将提高相关峰探测的准确性。