Comparison of the reactivities of 2-mercaptoaniline and 2-hydroxyaniline with 2-chloronicotinoyl chloride

The reaction between equimolar 2-chloronicotinoyl chloride and 2-mercaptopyridine in ClCH₂CH₂Cl, after 30 minutes refluxing in ClCH₂CH₂Cl solution, produced pyrido[2,3,b][1,5]benzothiazepin-5(H)one 7, and 6-[3-(2-benzothiazolyl)pyridin-2-yl)thio]-N-[3-(2-benzothiazolyl)pyridin-2-yl]aniline 8. In contrast, the reaction using the same reaction conditions between equimolar 2-chloronico- tinoyl chloride and 2-hydroxypyridine, produced the simple amide, 2-chloro-N-(2-hydroxyphenyl) nicotinamide 9. 2-Chloro-N-(2-mercaptophenyl)nicotinamide was considered to be a common intermediate in the formation of 7 and 8. The characterizations of 7–9 were achieved by X-ray crystallography. The conformations of 7 and 8 in the solid state can be described as “U” and “V”-shaped, respectively.     

KCl-MgCl2-LiCl 及 CaCl2-MgCl2-NaCl 熔盐系中MgCl2活度的简化亚正规模型

建立了一个描述KCl-MgCl2-LiCl及CaCl2-MgCl2-NaCl熔盐体系中MgCl2活度的溶液模型.模型假定将所讨论体系中的盐处理成独立的粒子而不是它们的离子形式,并对上述熔盐组元对之间的相互作用进行了分析,用随MgCl2成份变化的相互作用能可以较好地描述MgCl2的活度.与前人结果比较,本模型所用参数少且物理意义较明确.     

Na-Ti-Si氧化物Ti元素的化学状态分析

利用熔融方法制备了Na2O-TiO2-SiO2系统玻璃样品，用IR以及XPS等测试手段对系统玻璃样品结构进行了分析。结果表明：Na2O-SiO2-SiO2系统玻璃中Ti^4 离子可以部分地取代Si^4 离子的位置而以网络形成体的形式参与成玻。此外，通过对该系统玻璃的XPS钛元素的化学状态分析，认为该系统玻璃中Ti^4 离子存在[TiO4],[TiO6]等几种不同的微结构单元，并且随着玻璃中TiO2含量的增加，该系统玻璃中四方双锥结构的[TiO6]与正四面体结构的[TiO4]之比增大。     

2-（2-噻吩）乙胺合成工艺研究

研究了2-（2-噻吩）乙胺的合成工艺.噻吩甲醛与丙二酸经Knoevenagel-Doebner缩合生成3-（2-噻吩）丙烯酸,收率87%.3-（2-噻吩）丙烯酸与氯化亚砜和氨作用生成3-（2-噻吩）丙烯酰胺,收率91%;铜盐催化下用水合肼还原3-（2-噻吩）丙烯酰胺生成3-（2-噻吩）丙酰胺,收率99%;3-（2-噻吩）丙酰胺经Hoffman降解得2-（2-噻吩）乙胺,收率64%.由核磁共振氢谱、质谱和液谱对产物及中间体的结构和纯度进行了表征.     

Baicalin Ameliorates H2O2 Induced Cytotoxicity in HK-2 Cells through the Inhibition of ER Stress and the Activation of Nrf2 Signaling

Renal ischemia-reperfusion injury plays a key role in renal transplantation and greatly affects the outcome of allograft. Our previous study proved that Baicalin, a flavonoid glycoside isolated from Scutellaria baicalensis, protects kidney from ischemia-reperfusion injury. This study aimed to study the underlying mechanism in vitro. Human renal proximal tubular epithelial cell line HK-2 cells were stimulated by H₂O₂ with and without Baicalin pretreatment. The cell viability, apoptosis and oxidative stress level were measured. The expression of endoplasmic reticulum (ER) stress hallmarks, such as binding immunoglobulin protein (BiP) and C/EBP homologous protein (CHOP), were analyzed by western blot and real-time PCR. NF-E2-related factor 2 (Nrf2) expression was also measured. In the H₂O₂ group, cell viability decreased and cell apoptosis increased. Reactive Oxygen Species (ROS) and Glutathione/Oxidized Glutathione (GSH/GSSG) analysis revealed increased oxidative stress. ER stress and Nrf2 signaling also increased. Baicalin pretreatment ameliorated H₂O₂-induced cytotoxicity, reduced oxidative stress and ER stress and further activated the anti-oxidative Nrf2 signaling pathway. The inducer of ER stress and the inhibitor of Nrf2 abrogated the protective effects, while the inhibitor of ER stress and the inducer of Nrf2 did not improve the outcome. This study revealed that Baicalin pretreatment serves a protective role against H₂O₂-induced cytotoxicity in HK-2 cells, where the inhibition of ER stress and the activation of downstream Nrf2 signaling are involved.     

CO2-N2-TBAB和CO2-N2-THF体系的水合物平衡生成条件

利用等温压力搜索法测定了CO2-N2-TBAB与CO2-N2-THF体系的水合物平衡生成压力. 实验的压力范围为0.69~14.55 MPa,温度范围为275.75~288.15 K. 结果表明,TBAB与THF均可作为添加剂有效降低气体水合物的平衡生成压力. 在较低的药剂浓度下,CO2-N2-TBAB的水合物平衡生成压力低于CO2-N2-THF体系. 在较高的浓度下,两种体系的水合物平衡生成压力没有明显差别.     

Synthesis of an amphigel by the terpolymerization of 2-methyl-2-oxazoline, 2-alkyl-2-oxazoline,and bis-oxazoline

Summary The terpolymerization of 2-methyl-2-oxazoline, 2-alkyl-2-oxazoline (alkyl = n-butyl, n-octyl, n-dodecyl), and 2,2-tetramethylenebis(2-oxazoline) was carried out with methyl trifluoromethanesulfonate initiator. The obtained gel was isolated in a moderate yield after Soxhlet extraction. The resulting gel showed a characteristic property as an amphiphilic gel (amphigel), i.e., it was swollen both in water and in organic solvents such as N,N-dimethylformamide (DMF), n-propanol, 1,2-dichloroethane, diethyleneglycol dimethyl ether (diglyme) and toluene.     

The issue of selectivity in the direct synthesis of H2O2 from H2 and O2: the role of the catalyst in relation to the kinetics of reaction

The kinetic behavior in the direct synthesis of H₂O₂ with Pd–Me (Me = Ag, Pt) catalysts prepared by depositing the noble metals by electroless plating deposition (EPD) or deposition–precipitation (DP) methods on α-Al₂O₃ asymmetric ceramic membrane with or without a further surface coating by a carbon thin layer is reported. The effect of the second metal with respect to Pd-only catalysts considerably depends on the presence of the carbon layer on the membrane support. Several factors in the preparation of these membranes as well as the reaction conditions (temperature, concentration of Br⁻, pH) determine the selectivity in H₂O₂ formation, influencing the rate of the consecutive reduction of H₂O₂ (which is faster with respect to H₂O₂ decomposition on the metal surface) and/or of direct H₂ + O₂ conversion to H₂O. Defective Pd sites are indicated to be responsible for the two unselective reactions leading to water formation (parallel and consecutive to H₂O₂ formation), but the rate constants of the two reactions are differently influenced from the catalytic membrane characteristics. Increasing the noble metal loading on the membrane not only increases the productivity to H₂O₂, but also the selectivity, due to the formation of larger, less defective, Pd particles.     

粉煤灰及膨润土对Ni^2＋，Zn^2＋，Cd^2＋，Pb^2＋的吸附研究

研究了粉煤灰和膨润土对溶液中有毒重金属离子Ni~(2 )、Zn~(2 )、Pb~(2 )、Cd~(2 )的吸附能力。动态吸附试验显示,吸附过程是快速的。试验结果表明:粉煤灰对Zn~(2 )的吸附能力和膨润土相当,对Ni~(2 )、Cd~(2 )的吸附能力均大于膨润土。平衡吸附模型说明在高浓度下,Ni~(2 )、Zn~(2 )、Pd~(2 )在粉煤灰中,Ni~(2 )、Pd~(2 )在膨润土中的吸附符合Langmuir模式。试验还表明:随着吸附剂中Ni~(2 )、Zn~(2 )、Pb~(2 )、Cd含量增加,粉煤灰和膨润土对Ni~(2 )、Zn~(2 )、Pb~(2 )、Cd~(2 )的吸附百分率下降。     

Epoxidation of soybean oil by the methyltrioxorhenium-CH2Cl2/H2O2 catalytic biphasic system

We studied the methyltrioxorhenium (MTO)-CH₂Cl₂/H₂O₂ biphasic system for epoxidizing soybean oil. The reactions were optimized (reactant ratio, time, and temperature), which resulted in a better performance (higher conversion and selectivity) than those described in the literature. Total doublebond conversion and 95% selectivity were obtained in 2 h at room temperature. Furthermore, it was possible to reach desired epoxidation degrees by changing the oxidant and MTO amounts. The rhenium-epoxidized soybean oil remained stable in the absence of stabilizers for up to 30 d when stored at mild conditions.     

Study of Phase Relationships within the MgO-CuO-Cu2O-P2O5 System

The formation of the known compound Cu+Cu2+Mg3(PO4)3 by alternate reactions and its thermal stability were studied. The formation of solid solutions of the types Mg2-xCuxP2O7 and Mg3-xCux(PO4)2 was reexamined, mainly to aid in the identification of the products of decomposition of Cu+Cu2+Mg3(PO4)3. X-ray diffractometry patterns of Mg2-xCuxP2O7 varied gradually in the range 0 lessthan equal to x lessthan equal to 2, which indicates complete miscibility.     

优势区相图在A l-T i O2-C-ZrO2燃烧合成体系热力学分析中的应用

以TiO2, Al, C和ZrO2为原料, 燃烧合成制备Al2O3-TiC-ZrO2纳米复相陶瓷是一种方法简单、节时省能的新工艺. 对Al-TiO2-C-ZrO2体系进行了热力学分析,计算出该体系的绝热燃烧温度, 并利用Al-O-N,Ti-O-N,Zr-O-N,C-O-N四个体系的叠加优势区相图, 分析了各相间反应进行的趋势和最终稳定存在的平衡相. 热力学分析表明:绝热燃烧温度为2327 K, 燃烧合成产物包括Al2O3,TiC,ZrO2三相. XRD检测未发现其它杂相, 证实热力学分析结果可信.     

固体超强酸S_2O_8~(2-)/TiO_2-Al_2O_3催化合成乙酸戊酯的动力学研究

研究了以固体超强酸S2O82-/TiO2-A l2O3为催化剂合成乙酸戊酯的反应,在反应温度分别为100,108,116℃下,测出合成乙酸戊酯的动力学方程参数,建立了动力学方程式,并与无催化剂酯化反应的活化能及动力学方程式进行了比较。结果表明,最佳合成条件为:醇酸摩尔比1.3∶1,催化剂用量1 g,带水剂用量10 mL。固体超强酸S2O82-/TiO2-A l2O3使反应活化能明显降低,是合成乙酸戊酯的有效催化剂。     

On the Formation and Reactivity of 2-Alkylidene-benzopyrans and their 2-amino-5,6-benzo-2H-pyran precursors

A series of 2-amino-substituted 5,6-benzo-2H-pyrans 14 , 2-alkylidene-5,6-benzo-2H-pyrans 15 , and their dimers 17 are obtained, depending on the condition used, by the reaction of 2-hydroxy-benzaldehydes 1 with enamines 9 derived of (cyclo)aliphatic ketones. Compounds 14, 15 , and 17 can be transformed into 2-alkyl-benzopyrylium salts 16 or 2-[1-(2-hydroxyphenyl)-alken-2-yl]-benzopyrylium salts 23 by treatment with mineral acids. With aromatic aldehydes or the Vilsmeier reagent the compounds 14, 15 , or 17 are transformed into deeply colored 2-(aryl-alkenyl)-benzopyrylium perchlorates 25 or 2-(2-dialkylamino)-alkenyl-benzopyrylium salts 26 , respectively.     

Na2O-CaO-Al2O3-SiO2系统微晶玻璃的析晶动力学研究

Na2O-CaO-Al2O3-SiO2系统微晶玻璃是一种新型建筑材料,该材料不仅具有一定的力学性能,还具有良好的装饰效果.本文采用差热分析 (DTA)方法对 Na2O-CaO-Al2O3-SiO2系统微晶玻璃的析晶动力学参数进行了测定,研究了该系统微晶玻璃析晶动力学.其结果表明:随着CaO含量的增加,该系统微晶玻璃的析晶活化能E和动力学析晶参数k(Tp)总体上是上升的.晶化指数n均小于3,表明该系统微晶玻璃以表面析晶的方式析晶.     

Quantitative Analysis on the Influence of SiO2 Content on the Phase Behavior of ZrO2

The salient features of bioinert, chemical resistance, and high mechanical strength of synthetic ZrO₂ and the bioactivity characteristics of SiO₂ has been well‐known in biomedical applications. This study has been aimed at the synthesis and quantitative structural analysis of SiO₂‐stabilized tetragonal ZrO₂. The synthesis has been performed through sol–gel technique and the resultant characterization of the powders has been done through X‐ray diffraction (XRD) and X‐ray fluorescence (XRF) techniques. Quantitative analysis on the ZrO₂–SiO₂ binary oxide systems has been performed by Rietveld Refinement using GSAS‐EXPUGI software package. The results from this study have confirmed that SiO₂ concentration has played a major role in the stabilization of tetragonal ZrO₂. Lower SiO₂ concentration has resulted in the formation of mixture of any two different phases comprising of monoclinic ZrO₂ (P2₁/c symmetry) or cubic ZrO₂ (Fm‐3 m symmetry) or tetragonal ZrO₂ (P4₂/nmc symmetry), whereas higher SiO₂ concentration has resulted in the stabilization of single phase tetragonal ZrO₂ (P4₂/nmc symmetry).     

Meta-Analysis of APP Expression Modulated by SARS-CoV-2 Infection via the ACE2 Receptor

Alzheimer’s disease (AD) is characterized by the deposition of amyloid-beta (Aβ) plaques from improper amyloid-beta precursor protein (APP) cleavage. Following studies of inflammation caused by coronavirus-2019 (COVID-19) infection, this study investigated the impact of COVID-19 on APP expression. A meta-analysis was conducted utilizing QIAGEN Ingenuity Pathway Analysis (IPA) to examine the link between severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) and the modulation of APP expression upon virus binding the Angiotensin-converting enzyme-2 (ACE2) receptor. A Core Analysis was run on the infection by severe acute respiratory syndrome (SARS) coronavirus node, which included molecules affected by SARS-CoV-2, revealing its upstream regulators. Intermediary molecules were found between the upstream regulators and ACE2 and between ACE2 and APP. Activation of the upstream regulators downregulated the expression of ACE2 with a Z-score of −1.719 (p-value = 0.086) and upregulated APP with a Z-score of 1.898 (p-value = 0.058), showing a less than 10% chance of the results occurring by chance and pointing to an inverse relationship between ACE2 and APP expression. The neuroinflammation signaling pathway was the fifth top canonical pathway involved in APP upregulation. The study results suggest that ACE2 could be downregulated by SARS-CoV-2, resulting in APP upregulation, and potentially exacerbating the onset and progression of AD.     

盐酸普罗帕酮的合成工艺改进

由氯苄与丙二酸二乙酯经缩合、环合、水解、醚化、胺化、成盐得盐酸普罗帕酮，总收率２３％。     

The mechanism of the stereoregular polymerization of 2-vinylimidazole and 2-vinylbenzimidazole

Conformational energy calculations on poly(2-vinylimidazole) (PVI) and poly (2-vinylbenzimidazole) (FBI) indicated that the syndiotactic polymer would exhibit systematic intramolecular hydrogen bonding between side groups along the chain, while the isotactic polymers could not. This fact, together with our previous wor.k using solvent effects to produce highly syndiotactic poly(methacrylic acid) during radical polymerization, indicated that similar techniques could be applied in the radical polymerization, of 2-vinylimidazole and 2-vinylbenzimidazole. These mpnomers were polymerized over a wide temperature range using cobalt 60 gamma radiation as the initiator. The conditional probabilities obtained from NMR spectra of these polymers could be fit by second order Markov statistics (FBI) and extended second order Markov statistics (PVI). The difference reflects the effect of the bulkier benzimidazole side group. The nature of the conditional probabilities needed to fit the data for PVI suggest that the stereoregularity depended on the number of consecutive terminal r placements at the end of the growing radical. A marked solvent effect was observed was attributed to the hydrogen bonding strength of the solvent and its ability to disrupt the r directing polymer hydrogen bonding.     

A coupled phase diagram experimental study and thermodynamic optimization of the Li2O-CaO-Al2O3 and Li2O-CaO-SiO2 systems,and prediction of the phase diagrams of the Li2O-CaO-Al2O3-SiO2 system

A coupled experimental phase diagram study and thermodynamic modeling of the Li₂O-CaO-Al₂O₃ and Li₂O-CaO-SiO₂ systems was conducted at 1 atm total pressure. Differential scanning calorimetry (DSC) measurements were performed in the Li₂O-CaO-Al₂O₃ and Li₂O-CaO-SiO₂ systems. In addition, the phase relations in the Li₂O-CaO-Al₂O₃ system were determined by equilibration/quenching experiments at 1643 and 1743 K, and the phases were characterized with X-ray diffraction (XRD) and Electron-probe micro analysis-wavelength dispersive spectroscopy (EPMA-WDS). The absence of ternary compounds or solid solutions was confirmed. Congruent melting of Li₂CaSiO₄ compound in the Li₂O-CaO-SiO₂ system was determined at 1350 ± 5 K. Thermodynamic optimization of the Li₂O-CaO-Al₂O₃ and Li₂O-CaO-SiO₂ systems was carried out based on new phase diagram experiments and critically evaluated literature data. The phase diagrams of the quaternary Li₂O-CaO-Al₂O₃-SiO₂ system were predicted using the thermodynamic models with optimized model parameters.