CsPbX3 Quantum Dots for Lighting and Displays: Room‐Temperature Synthesis,Photoluminescence Superiorities,Underlying Origins and White Light‐Emitting Diodes

Recently, Kovalenko and co‐workers and Li and co‐workers developed CsPbX₃ (X = Cl, Br, I) inorganic perovskite quantum dots (IPQDs), which exhibited ultrahigh photoluminescence (PL) quantum yields (QYs), low‐threshold lasing, and multicolor electroluminescence. However, the usual synthesis needs high temperature, inert gas protection, and localized injection operation, which are severely against applications. Moreover, the so unexpectedly high QYs are very confusing. Here, for the first time, the IPQDs' room‐temperature (RT) synthesis, superior PL, underlying origins and potentials in lighting and displays are reported. The synthesis is designed according to supersaturated recrystallization (SR), which is operated at RT, within few seconds, free from inert gas and injection operation. Although formed at RT, IPQDs' PLs have QYs of 80%, 95%, 70%, and FWHMs of 35, 20, and 18 nm for red, green, and blue emissions. As to the origins, the observed 40 meV exciton binding energy, halogen self‐passivation effect, and CsPbX₃@X quantum‐well band alignment are proposed to guarantee the excitons generation and high‐rate radiative recombination at RT. Moreover, such superior optical merits endow them with promising potentials in lighting and displays, which are primarily demonstrated by the white light‐emitting diodes with tunable color temperature and wide color gamut.     

Comparative study on iodide and bromide isotopic exchange reactions by application of radioactive tracer technique

In the present investigation, a short lived radioactive tracer isotopes ¹³¹I and ⁸²Br were used to study the kinetics of isotopic exchange reactions. For bromide isotopic exchange reaction, the calculated values of specific reaction rate (min⁻¹), and amount of bromide ions exchanged (mmol) were obtained higher than that for iodide isotopic exchange reaction under identical experimental conditions. For both the exchange reactions it was observed that when the concentration of ionic solution was increased twice, the␣percentage of ions exchanged increases sharply at nearly same specific reaction rate, indicating that concentration greatly influences the exchange reactions.     

Synthesis and ionic conductivities of lithium-doped morpholinium salts

A series of a new type of ionic liquids was prepared. The synthesis and purification procedure of N-alkyl-N-methylmorpholinium bromide, N-alkyl-N-methylmorpholinium tetrafluoroborate, N-alkyl-N-methylmorpholinium hexafluorophosphate, and N-alkyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide were presented. Thermal properties of morpholinium salts and ionic conductivities of lithium-doped ionic liquids were measured in the temperature range of 303.15 to 323.15 K. In the case of the pure ionic liquids, the ionic conductivities were 10^-4 S·cm^-1.     

BrФnsted-Lewis双酸性离子液体的合成与应用

BrФnsted-Lewis双酸性离子液体同时具备B酸性和L酸性,是融合双酸性固体酸与离子液体的特征发展起来的一类新型催化剂。本文综述了近年来B-L双酸性离子液体的合成、表征及催化剂应用等方面的进展,在此基础上,总结出B-L双酸性离子液体的三个特征。其一,利用一种催化剂就可以催化分别需要B酸和L酸催化的分步反应,使反应一锅化,简洁可控。其二,B酸性和L酸性之间存在相互增强的协同作用,使其具有更好的催化性能,或可提高反应转化率或产物选择性。其三,液体催化剂在传质和扩散等方面均优于双酸性固体酸。上述特征使B-L双酸性离子液体替代并超越传统酸性催化剂成为可能,在工业应用中显示良好的发展前景。     

AS/C_(12)-4-C_(12)·2Br/醇/己烷/盐水中相微乳液的研究

以AS/C12-4-C12.2Br/ROH/己烷/盐水系统为对象,研究了表面活性剂配比,表面活性剂用量,醇的种类,醇度,盐度等对系统相态的影响,结果显示:AS/C12-4-C12.2Br复配具有较好的协同效应,以AS/C12-4-C12.2Br复配物为表面活性剂所制备的中相微乳液的最佳体积比用单一表面活性剂形成中相微乳液体积大,形成中相微乳液的较佳条件是:以丁醇为助表面活性剂,w(AS)∶w(C12-4-C12.2Br)复配比为10∶1,c(NaCl)=14%∶c(ROH)=4%,中相微乳液的体积达到3.3 mL。     

Ionic liquid mediated esterification of alcohol with acetic acid

Highly efficient esterification of alcohols with acetic acid by using a Br?nsted acidic ionic liquid, i.e., 1-methyl-2-pyrrolidonium hydrogen sulfate ([Hnmp]HSO₄), as catalyst has been realized. The turnover numbers (TON) were able to reach up to 11000 and turnover frequency (TOF) was 846. The catalytic system is suitable for the esterification of long chain aliphatic alcohols, benzyl alcohol and cyclohexanol with good yields of esters. The procedure of separating the product and catalyst is simple, and the catalyst could be reused. [Hnmp]HSO₄ had much weaker corrosiveness than H₂SO₄. The corrosive rate of H₂SO₄ was 400 times more than that of [Hnmp]HSO₄ to stainless steel.     

双效直燃型溴化锂吸收式冷热水机组及其经济性分析

本文简要的介绍了直燃型溴化锂吸收式冷热水机组的特点，流程和运行方式，并就初期投资和运行费用与其他的几种制冷方案做了比较。     

Alkylation of Hydroquinone with tert-Butanol Catalyzed by Polymer-supported Sulfonimide

Polystyrene with pendant perfluorobutylsulfonylimide (PPFSI) was developed as a novel polymer-supported strong acid catalyst for alkylation of hydroquinone (HQ) with tert-butanol (TBA), and highly selective synthesis of 2-tert-butyl hydroquinone (2-TBHQ) was investigated over PPFSI under various experiment conditions. When the molar ratio of TBA to HQ was 1.2:1, using 3 mol% of PPFSI as catalyst in 1,2-dichloroethane at 130 °C for 5 h, the maximum of selectivity (85.9%) of 2-TBHQ was obtained while the conversion of HQ was 76.7%. Compared with other solid acid catalysts PPFSI was found to be a very effective and reusable catalyst for alkylation of hydroquinone with tert-butanol.     

蒙药鹅绒藤药材质量标准研究

目的:初步建立蒙药材鹅绒藤质量标准,为本药材质量检验提供实验依据。方法:按2010版《中国药典》附录相应测定法对蒙药材鹅绒藤的水分、总灰分、酸不溶灰分、水溶性浸出物和醇溶性浸出物等质量方面进行了较为全面和系统的研究。结果:蒙药材鹅绒藤的水分含量为7.21%~8.12%;总灰分平均含量为12.92%;95%乙醇浸出物含量(热浸法)为11.94%~19.11%。结论:初步建议蒙药材鹅绒藤的质量标准,含水量不得超过10.0%,总灰分不得高于15.0%,酸不溶性灰分不得高于1.5%,冷浸法水溶性浸出物量不得低于19.0%,95%乙醇浸出物量不得低于11.0%。