Stability of O3 + N2, O3 + O2 and O3 + CO2 double hydrates: DFT study

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Influence of halide mixing on thermal and photochemical stability of hybrid perovskites: XPS studies

The effect of I^–/Cl^–and I^–/Br^–mixing on the thermal and photochemical degradation of organometallic perovskite MeNH₃PbI₃ (MAPbI₃) was studied by X-ray photoelectron spectroscopy, which revealed the opportunity to essentially increase the photo and thermal stabilities of the material depending on the level and position of halide-mixing. The largest positive effect was observed for the small concentration of chloride substituent (MAPbI_2.7Cl_0.3), while the full halide substitution (MAPbBr₃) had a negative effect on the stability of hybrid perovskite.     

Reactions of chromone-3-carboxamides with 2-cyanothioacetamides

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Y2O3,CeO2掺杂的Mg-PSZ陶瓷材料研究

采用传统的陶瓷工艺制备少量掺杂Ｙ２Ｏ３,ＣｅＯ２的Ｍｇ－ＰＳＺ陶瓷,材料在较低的温度下烧结致密并实现了微晶化,探讨了Ｙ２Ｏ３,ＣｅＯ２的复合稳定作用和１１００℃热处理过程对材料相组成、显微结构和力学性能的影响。经１１００℃适当时间热处理,Ｙ２Ｏ３,ＣｅＯ２的复合稳定作用有效报制亚共析分解反应发生,优化调整ｃ－ＺｒＯ２晶粒中的ｔ－ＺｒＯ２析出体成核长大过程。断裂特征为穿晶、沿晶兼有,相变增韧和微裂纹     

Transport properties of iron-doped BaZr0.9Yb0.1O3–δ

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Novel 2-alkoxy- and 2-alkylthio-substituted pyrimidines containing 2-(1-methyl-1H-pyrrol-2-yl)vinyl moieties: optical and electrochemical properties

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TSL and EPR studies of SrBPO5 doped with CeO2 and co-doped with CeO2 and Sm2O3

Thermally stimulated luminescence (TSL) and electron paramagnetic resonance (EPR) investigations were carried out on gamma irradiated SrBPO₅ samples doped with CeO₂ and co-doped with CeO₂ and Sm₂O₃. On gamma-irradiation at room temperature, BO₃ ^2–, O₂ ^– and O^– radicals were produced. It was seen that the O^– radical ion disappeared in the sample annealed at 500 K. It is proposed that the recombination between trapped electrons and O^– radical ions results in transfer of recombination energy to the impurity centre Ce³⁺ resulting in TSL glow peak at 485 K. In the case of co-doped samples energy transfer occurs between Ce³⁺ to Sm³⁺ resulting in increase in the intensity of glow peak at 485 K.The authors are grateful to Dr. V. K. Manchanda, Head, Radiochemistry Division, BARC for his keen interest and encouragement during the course of this work.     

Y2O3和CeO2对氮化硅烧结性能的影响

研究了Y2O3,CeO2的添加量在不同烧结温度下对Si3N4烧结性能的影响，分析了其助烧作用及晶界二次小晶粒形成的机制。结果表明，添加Y2O3,CeO2的Si3N4其烧结性能良好。Y2O3添加5％（此时Al2O3含量为4％）及CeO2为8％时对制品烧结促进作用最大。热处理后在Si3N4晶界获得结晶完美的二次小晶粒，使晶界玻璃相大为下降，为Si3N4高温力学性能的提高奠定结构基础。     

The reaction of 4-(1,3,2-benzodioxaphosphol-2-yloxy)-3-tert-butylpent-4-en-2-one with hexafluoroacetone

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Thermal behaviour of CO2 laser-irradiated CeO2 doped with Yb2O3

Results concerning the thermal behaviour of Yb₂O₃-doped CeO₂ samples irradiated with CO₂ laser beams in continuous wave are presented.

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Zusammenfassung Es werden Ergebnisse einer Untersuchung des thermischen Verhaltens von CeO₂-Proben dargelegt, die mit CO₂-Laser bestraht wurden.

     

Relativistic effects in the NMR spectra of compounds containing heavy chalcogens

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Fluorescence modulation of eosin Y in a PMMA film by diarylethene switching

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Synthesis and antihypotensive properties of 2-amino-2-thiazoline analogues with enhanced lipophilicity

In a search of nitric oxide synthase inhibitors with prolonged vasoconstrictive activity, a series of lipophilic cyclohexafused 2-amino-2-thiazolines was obtained via cyclization of tert-butyl- or benzoyl-substituted N-(cyclohex-2-en-1-yl)thioureas. The crystal structure of intermediate N-[(3aRS,7aSR)- 3a,4,5,6,7,7a-hexahydro-1,3-benzothiazol-2-yl]benzamide hydrobromide was determined by X-ray analysis. One compound was found to cause pronounced and prolonged vasoconstrictive effect after single injection to the Wystar rats with lipopolysaccharide induced acute endotoxic (vasodilatation) shock.     

3-(4-Phosphoryl-4-methyl-2-oxopentyl)-3-hydroxyindolin-2-ones,the first phosphorus analogues of natural convolutamydines

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Reactions of carbamoylated amino enones with 3-substituted chromones for the preparation of 2-pyridones and chromeno[4,3-b]pyridine-2,5-diones

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Y2O3和CeO2复合掺杂ZrO2纳米晶的制备与表征

以ZrOCl2.8H2O,Y2O3,Ce（NO3）3.5.5H2O为原料,NH3.H2O作沉淀剂,少量表面活性剂PE作分散剂,采用反向共沉淀-喷雾干燥法,结合物理、化学分散技术,成功地制备了Y2O3,CeO2复合掺杂ZrO2纳米粉末。通过DSC-TG,XRD,XPS,BET和SEM等方法对所制得粉末进行了表征。结果表明：以Ce0.1Y0.1Zr0.8O1.95化学计量比制备的多元氢氧化物胶体经过喷雾干燥处理后,在500℃基本完成水合氧化物的分解,577℃附近完成由非晶相向立方相的转变;经过580-1000℃煅烧后,CeO2和Y2O3已经完全固溶到ZrO2中,形成类质同相体,该粉末系列均属于立方相萤石结构;掺杂进入ZrO2晶格中的Ce呈＋4价形式存在;比表面积由22.0 m^2.g^-1（580℃煅烧）减至4.97 m^2.g^-1（1000℃煅烧）;SEM结果显示800℃煅烧的该粉末颗粒尺寸分布均匀,多呈类球状,且粒径在50-80 nm。     

Reaction of 3-azidoisoxazoles with active methylene compounds

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Deprotonation of 1,1′-methylenebis[4-tert-butyl-2-(diphenylphosphino)-benzene] and its analogues: synthesis and crystal structure of {5-But-2-[4-But-2-(Ph2P)C6H3(Ph)CH]C6H3P(Ph)K(OEt2)}2

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Viscosity and thermal expansion of soda-lime-silica glass doped with Gd2O3 and Y2O3

In order to reveal the effects of rare earth elements on the rheological behavior of silicate melt, the properties of viscosity and thermal expansion of soda-lime-silica glass doped with Gd₂O₃ and Y₂O₃ were investigated by the rotating crucible viscometer and dilatometry. The results show that, introduction of Gd₂O₃ and Y₂O₃ increases the coefficient of thermal expansion and decreases viscosity of soda-lime-silica glass. When the amount of Gd₂O₃ and Y₂O₃ increases from 0 to 1.00 mol%, the coefficient of thermal expansion of soda-lime-silica glass increases firstly from 7.67 to 7.79 and 8.05, and then decreases to 7.78 and 7.66 ( × 10⁻⁶ °C⁻¹) respectively. In the case of melting temperature, its value decreases from 1830K to 1714 K, and then elevates to 1727 K as the content of Gd₂O₃ up to 1.00 mol%, however, as Y₂O₃ content increases from 0 to 1.00 mol% the melting temperature decreases monotonously from 1830K to 1737 K. The viscosity, melting temperature and coefficient of thermal expansion of soda-lime-silica glasses co-doped with Gd₂O₃ and Y₂O₃ are larger, comparing with glasses doped solely with Gd₂O₃ or Y₂O₃. The effect of co-doping with Gd₂O₃ and Y₂O₃ on thermal expansion and viscosity properties of soda-lime-silica glass, which is similar with the mixed-alkali effect in silicate glasses, is also observed.     

Solvent-free silica gel mediated decarboxylation of C–O coupling products of β-diketones and β-oxo esters with malonyl peroxides

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