LC Determination of Curcumin in Dog Plasma for a Pharmacokinetic Study

A rapid, simple, and sensitive high-performance liquid chromatographic method for quantification of curcumin in dog plasma has been developed and validated. After addition of the internal standard (berberine), plasma was acidified and extracted with ethyl acetate. Analysis was performed on a C₁₈ column. The mobile phase was acetonitrile–5% acetic acid, 52:48 (v/v) and the flow rate 1.0 mL min^?1. The eluent was monitored at 425 nm. Chromatographic separation was achieved in less than 7 min and the calibration plot was linear over the concentration range 2–128 ng mL^?1. Intra- and inter-assay variability were less than 7.3%. The accuracy ranged from 98.7 to 105.0%. The method was successfully applied to a pharmacokinetic study of curcumin in dogs.     

~(13)C-NMR研究聚丁二烯长支链支化

本文研究了用不同催化体系制备的聚丁二烯和加氢的聚丁二烯的~(13)C-NMR谱图。结合GPC测定支化度的数据,提出了二种可能的支化结构。以Ni及Co催化体系聚合的试样,支化点可能位于顺-1,4主链双键的α-次甲基上;而由Ni+Mo催化体系聚合的试样,可能为1,2-乙烯基的双键打开接长支链。     

Anodic oxidation of hydrazine at carbon nanotube powder microelectrode and its detection

Carbon nanotube powder microelectrodes (CNTPMEs) were used to study the anodic oxidation of hydrazine at Carbon nanotube (CNT)-the novel carbon material. It was found that the electrochemical behaviours were greatly improved at CNTs, indicating that the anodic oxidation could be catalyzed at CNTs. The kinetics parameters of this process were calculated, the heterogeneous electron transfer rate constant k was 0.0019 cm s(-1), (1-alpha)n(alpha) was 0.22. The CNTPMEs were also found with high sensitivity for hydrazine detection, could be used as hydrazine sensors.     

全硅MCM-41担载的加氢脱硫催化剂的TPR研究

用TRP技术研究了以全硅MCM-41(Si-MCM-41)和HNO3交换的全硅MCM-41(H-MCM-41)为载体制备的Ni-Mo、Co-Mo和Ni-W加氢脱硫(HDS)催化剂的还原性能，并以0．8(wt)％二苯并噻吩(DBT)的十氢萘溶液为模型化合物，在高压固定床反应器上考察了上述催化剂的加氢脱硫(HDS)反应性能。结果表明，Si-MCM-41经稀HNO3交换后，所担载的Ni-Mo和Ni-W催化剂还原性能、HDS活性和加氢活性有显著变化，但对Co-Mo催化剂影响不大。这说明在Ni-Mo／H-MCM-41和Ni-W／H-MCM-41中可能存在氢溢流现象，DBT的HDS活性与载体表面酸性和氢溢流有关。     

Boosting the synthesis of value-added aromatics directly from syngas via a Cr2O3 and Ga doped zeolite capsule catalyst

Even though the transformation of syngas into aromatics has been realized via a methanol-mediated tandem process, the low product yield is still the bottleneck, limiting the industrial application of this technology. Herein, a tailor-made zeolite capsule catalyst with Ga doping and SiO₂ coating was combined with the methanol synthesis catalyst Cr₂O₃ to boost the synthesis of value-added aromatics, especially para-xylene, from syngas. Multiple characterization studies, control experiments, and density functional theory (DFT) calculation results clarified that Ga doped zeolites with strong CO adsorption capability facilitated the transformation of the reaction intermediate methanol by optimizing the first C–C coupling step under a high-pressure CO atmosphere, thereby driving the reaction forward for aromatics synthesis. This work not only reveals the synergistic catalytic network in the tandem process but also sheds new light on principles for the rational design of a catalyst in terms of oriented conversion of syngas.

The single-pass conversion of syngas into para-xylene was realized using a bifunctional catalyst Cr₂O₃/Ga-ZSM-5@SiO₂. The Ga species facilitates the methanol consumption process by C–C coupling optimization, enhancing the yield of the target aromatics.     

聚乙烯醇存在下锇(Ⅱ)-氯化亚锡-结晶紫体系超高灵敏显色反应的研究

本文研究了聚乙烯醇存在下锇(Ⅱ)-氯化亚锡-结晶紫体系的超高灵敏显色反应。反应物λ_(max)=555nm,ε_(555)=1.52×10~6L·mol~(-1)·cm~(-1)。锇含量为(0～4.8)μg/25ml时符合比尔定律。对共存离子的干扰和分离进行了实验,拟定的方法可用于矿石和一些含低品位锇物料的分析。     

Lanthanide MOFs for inducing molecular chirality of achiral stilbazolium with strong circularly polarized luminescence and efficient energy transfer for color tuning

We present herein an innovative host–guest method to achieve induced molecular chirality from an achiral stilbazolium dye (DSM). The host–guest system is exquisitely designed by encapsulating the dye molecule in the molecule-sized chiral channel of homochiral lanthanide metal–organic frameworks (P-(+)/M-(−)-TbBTC), in which the P- or M-configuration of the dye is unidirectionally generated via a spatial confinement effect of the MOF and solidified by the dangling water molecules in the channel. Induced chirality of DSM is characterized by solid-state circularly polarized luminescence (CPL) and micro-area polarized emission of DSM@TbTBC, both excited with 514 nm light. A luminescence dissymmetry factor of 10⁻³ is obtained and the photoluminescence quantum yield (PLQY) of the encapsulated DSM in DSM@TbTBC is ∼10%, which is close to the PLQY value of DSM in dilute dichloromethane. Color-tuning from green to red is achieved, owing to efficient energy transfer (up to 56%) from Ln³⁺ to the dye. Therefore, this study for the first time exhibits an elegant host–guest system that shows induced strong CPL emission and enables efficient energy transfer from the host chiral Ln-MOF to the achiral guest DSM with the emission color tuned from green to red.

Homochiral Ln-MOFs are synthesized to encapsulate achiral dyes to induce strong circularly polarized luminescence with a luminescence dissymmetry factor of 10⁻³.     

Low-temperature growth and photoluminescence property of ZnS nanoribbons

At a low temperature of 450 degrees C, ZnS nanoribbons have been synthesized on Si and KCl substrates by a simple chemical vapor deposition (CVD) method with a two-temperature-zone furnace. Zinc and sulfur powders are used as sources in the different temperature zones. X-ray diffraction (XRD), selected area electron diffraction (SEAD), and transmission electron microscopy (TEM) analysis show that the ZnS nanoribbons are the wurtzite structure, and there are two types-single-crystal and bicrystal nanoribbons. Photoluminescence (PL) spectrum shows that the spectrum mainly includes two parts: a purple emission band centering at about 390 nm and a blue emission band centering at about 445 nm with a weak green shoulder around 510 nm.     

无亲水基团取代的四苯基卟吩类LB膜的制备与表征

拉制了4种无亲水基团的四苯基卟吩LB膜,用透射电镜、荧光寿命、荧光光谱和紫外-可见光谱测量表征了膜的形貌和结构,发现膜中卟吩主要以聚集体形式存在。