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为了解决生物柴油制备过程中副产物甘油过剩、碳酸甘油酯产率低和催化剂回收困难的问题，以聚乙二醇600（PEG-600）为模板和分散剂，采用溶胶凝胶法制备镁铁氧体（MgFe2O4），以其为载体，KNO3为活性组分前驱体，采用浸渍法制备K2O/MgFe2O4磁性固体碱催化剂。通过X射线衍射、 X射线光电子能谱、扫描电镜、CO2程序升温脱附(CO2-TPD)和磁性分析对催化剂进行表征，并将催化剂用于甘油与碳酸二甲酯酯交换制备碳酸甘油酯的反应中，考察其催化性能。结果表明：制备的K2O/MgFe2O4形成了K-Fe-Mg键，K2O/MgFe2O4表面呈霉菌状，具有较多的中强碱位点和强碱位点，且具有较好的磁性；在PEG-600加入量10 g（硝酸镁1.5 g、硝酸铁4.71 g）、反应温度105 ℃、反应时间2 h、催化剂用量3%、甘油与碳酸二甲酯物质的量比1∶ 2的条件下，甘油转化率可达到99.53%，碳酸甘油酯产率可达到96.36%，且制备的催化剂重复使用性能良好，在重复使用5次后，碳酸甘油酯产率仍可达80.14%。综上，所制备的催化剂具有高甘油转化率、高碳酸甘油酯产率、重复使用性能高（通过外部磁场即可回收）等优点，有望实现工业化。In order to solve the problems of glycerol excess as a by-product in the production process of biodiesel, low yield of glycerol carbonate and difficult recovery of catalyst, with polyethylene glycol 600(PEG-600) as templet and dispersant, magnesium ferrite (MgFe2O4) was prepared by sol-gel method and magnetic solid base catalyst K2O/MgFe2O4 was prepared by impregnation method using MgFe2O4 as the carrier and KNO3 as the precursor of the active component.The catalyst was characterised by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, CO2 procedure temperature rise desorption and magneometer, and the catalytic performance was investigated by using the catalysts in the reaction of transesterification of glycerol with dimethyl carbonate to produce glycerol carbonate. The results showed that the prepared K2O/MgFe2O4 formed K-Fe-Mg bonds, the surface of K2O/MgFe2O4 was mould-like with more medium-strong base sites and strong base sites, and it had good magnetic properties. Under the conditions of PEG-600 addition amount 10 g(Mg(NO3)2 1.5 g, Fe(NO3)3 4.71 g), reaction temperature 105 ℃, reaction time 2 h, catalyst dosage 3%, and the molar ratio of glycerol to dimethyl carbonate 1∶ 2, the conversion rate of glycerol could reach 99.53%, and the yield of glycerol carbonate could reach 96.36%. The prepared catalyst had good reusability, and the yield of glycerol carbonate was still as high as 80.14% after 5 times of reuse. In conclusion, the prepared catalyst has the advantages of high glycerol conversion, high glycerol carbonate yield, and high reusability (easier recovery through an external magnetic field), which is expected to achieve industrialisation.

针对由甘油制备碳酸甘油酯的酯交换法中催化剂制备方法复杂、活性组分易流失等问题，采用一锅法制备了Li掺杂CeO2固体碱催化剂。对催化剂进行了X射线衍射(XRD)、扫描电镜（SEM）、透射电镜（TEM）、BET、X射线光电子能谱(XPS)、CO2程序升温脱附(CO2-TPD)等表征。以甘油转化率和碳酸甘油酯产率为指标，对催化剂进行了筛选，并采用单因素实验对甘油酯交换合成碳酸甘油酯的工艺条件进行了优化，同时考察了催化剂的重复使用性能。结果表明:Li与CeO2之间能够产生协同作用，Li的掺杂能够明显增加CeO2的中强碱活性位点；Li、Ce与柠檬酸物质的量比为0.3∶ 1∶ 1时，催化剂催化活性最好；甘油酯交换合成碳酸甘油酯的最优反应条件为反应温度100 ℃、反应时间2.0 h、催化剂用量为甘油质量的1%、甘油与碳酸二甲酯物质的量比1∶ 2，在此条件下甘油转化率为90.16%，碳酸甘油酯收率为90.04%；催化剂在重复使用5次后活性无明显下降。采用一锅法制备的Li掺杂CeO2固体碱催化剂具有良好的催化性能，可用于催化甘油酯交换合成碳酸甘油酯。 Aiming at the problems of complex preparation method and easy loss of active components of catalyst in the transesterification method of preparing glycerol carbonate from glycerol, Li doped CeO2 solid base catalyst was prepared by one pot method. The catalyst was characterized by XRD, SEM, TEM, BET, XPS and CO2-TPD. With conversion rate of glycerol and yield of glycerol carbonate as indexes, the catalyst was screened and the conditions of transesterification of glycerol to prepare glycerol carbonate were optimized by single factor experiment. The reusability of the catalyst was investigated. The results showed that there was a synergistic effect between Li and CeO2, and Li doping could significantly increase the medium and strong base sites of CeO2.When molar ratio of Li, Ce and citric acid was 0.3∶ 1∶ 1, the catalyst had the best activity. The optimal reaction conditions were obtained as follows: reaction temperature 100 ℃, reaction time 2.0 h, catalyst dosage 1% of glycerol mass, and molar ratio of glycerol to dimethyl carbonate 1∶ 2. Under these conditions, the conversion rate of glycerol was 90.16% and the yield of glycerol carbonate was 90.04%, and the activity of the catalyst did not decrease significantly after reused for five times.Li doped CeO2 solid base catalyst prepared by one pot method has good catalytic performance, and can be used to catalyze synthesis of glyceryl carbonate by transesterification of glycerol.

为改善现有季戊四醇异硬脂酸酯生产工艺存在的反应时间长、反应温度高、效率低等问题，研究采用对甲苯磺酸催化季戊四醇与异硬脂酸酯化合成季戊四醇异硬脂酸酯。以异硬脂酸酯化率为考察指标，利用单因素实验和正交实验对酯化工艺条件进行优化，对酯化粗产物进行除酸提纯处理，并对粗产物进行红外光谱分析，对除酸提纯产物进行质谱分析、热重分析及性能指标测定。结果表明：最优的酯化反应工艺条件为反应时间5 h、反应温度140 ℃、催化剂用量1%（基于反应总投料质量）、异硬脂酸与季戊四醇物质的量比值4.3，在此条件下酯化率为99.27%，粗产物酸值（KOH）为13.26 mg/g。红外光谱结果表明此酯化反应合成了季戊四醇异硬脂酸酯，质谱鉴定结果显示主要合成产物为季戊四醇四异硬脂酸酯。经脱酸处理，产物的酸值（KOH）降为3.23 mg/g，与市售产品接近，热重分析及性能指标测定结果显示提纯产物具有优异的热稳定性，良好的黏温性能、优异的低温流动性及良好的安全性。优化的对甲苯磺酸催化合成季戊四醇异硬脂酸酯工艺具有能耗低、产物品质高的优点。 In order to improve the existing production process of pentaerythritol isostearate, which has the problems of long reaction time, high reaction temperature and low efficiency, the synthesis of pentaerythritol isostearate by esterification of pentaerythritol with isostearic acid catalyzed by p-toluenesulfonic acid was carried out.The esterification process conditions were optimized using single factor experiment and orthogonal experiment with esterification rate of isostearic acid as the index.The crude product of esterification was purified by deacidification, the crude product was analyzed by infrared spectroscopy, and the purified product was analyzed by mass spectrometry, thermogravimetric analysis, and its performance indexes were also determined.The results showed that the optimal process conditions were obtained as follows: reaction time 5 h, reaction temperature 140 ℃, dosage of catalyst 1%(based on the total mass of substrates), and the molar ratio value of isostearic acid to pentaerythritol 4.3. Under these conditions, the esterification rate was 99.27% and the acid value of the crude product was 13.26 mgKOH/g.The infrared spectroscopy results indicated that the esterification reaction synthesized pentaerythritol isostearate, and mass spectrometry identification results showed that the main synthesized product was pentaerythritol tetraisostearate. After deacidification, the acid value of the product was reduced to 3.23 mgKOH/g, which was close to that of the commercial product. The results of thermogravimetric analysis and the performance indexes showed that the purified product had excellent thermal stability, good viscosity-temperature properties, excellent low-temperature fluidity and good safety. The optimized process of synthesis of pentaerythritol isostearate catalyzed by p-toluenesulfonic acid had advantages of low energy consumption and high product quality.

为了解决甘油合成碳酸甘油酯产率较低及反应完成后催化剂的回收问题，制备磁性水滑石LDH-Fe3O4，以KNO3为活性组分前驱体对其改性制备磁性固体碱催化剂K2O/LDO-γ-Fe2O3，对KNO3的负载量进行考察，对K2O/LDO-γ-Fe2O3进行X射线衍射、 扫描电子显微镜、 CO2程序升温脱附、BET及磁化强度表征，采用单因素试验对K2O/LDO-γ-Fe2O3催化甘油酯交换合成碳酸甘油酯的工艺条件进行了优化，并对K2O/LDO-γ-Fe2O3的重复使用性能进行了考察。结果表明：KNO3负载提供了大量的碱性位点，有利于催化剂催化活性的提高，KNO3的最佳负载量为10%（以LDH-Fe3O4质量计），K2O/LDO-γ-Fe2O3的饱和磁化强度为10.47 emu/g；K2O/LDO-γ-Fe2O3催化酯交换最佳反应条件为反应温度100 ℃、反应时间2 h、催化剂用量3%（以甘油质量计）、甘油与碳酸二甲酯物质的量比1∶ 2，在此条件下碳酸甘油酯产率为92.12%；催化剂重复使用5次后碳酸甘油酯产率高达89.35%，相比镁铝水滑石，K2O/LDO-γ-Fe2O3催化反应时间短，反应试剂用量少。K2O/LDO-γ-Fe2O3催化剂具有磁性，可在外加磁场作用下与反应体系分离，并且在数次循环使用中保持较高的活性，经济成本降低，在工业生产碳酸甘油酯中有很好的应用前景。In order to solve the problems of the low yield of glycerol carbonate synthesized with glycerol and the recovery of the catalyst after the reaction, the magnetic hydrotalcite LDH-Fe3O4 was prepared and modified by KNO3 as the active component precursor to prepare magnetic solid base catalyst K2O/LDO-γ-Fe2O3.The KNO3 loading amount of the catalyst was studied.The K2O/LDO-γ-Fe2O3 was characterized by X-ray diffraction, scanning electron microscopy, CO2-TPD, BET and magnetization intensity. The process conditions of the K2O/LDO-γ-Fe2O3-catalyzed transesterification of glycerol for the synthesis of glycerol carbonate were optimized using single factor experiment. The reusability of K2O/LDO-γ-Fe2O3 was investigated. The results showed that KNO3 provided a large number of alkaline sites, which facilitated the catalytic activity of the catalyst,and the optimal loading amount was 10%(based on the mass of LDH-Fe3O4). The saturation magnetization intensity of K2O/LDO-γ-Fe2O3 was 10.47 emu/g. The optimal transesterification conditions were as follows: reaction temperature 100 ℃, reaction time 2 h, catalyst dosage 3%(based on the mass of glycerol), and molar ratio of glycerol to dimethyl carbonate 1∶ 2. Under the optimal conditions, the glycerol carbonate yield was 92.12%. The yield of glycerol carbonate reached 89.35% after five repetitions of the catalyst. The K2O/LDO-γ-Fe2O3 catalytic reaction time was shorter and the amount of reaction reagent was less than that of Mg-Al hydrotalcite. In conclusion, the magnetic catalyst prepared is magnetic and can be separated from the reaction system under the action of an applied magnetic field, and can maintain high activity in several cycles with reduced economic costs,and has a good application prospect in industrial production of glycerol carbonate.

为了制备适用于催化合成单癸酸甘油酯（GMC）的催化活性高、重复利用性强以及热稳定性好的固体酸催化剂，以钛酸四丁酯为钛源、正硅酸乙酯为硅源，采用软模板法在酸性条件下合成Ti-SBA-15，再通过有机接枝的方法引入磺酸基团，制备了同时含有Bronsted酸位点和Lewis酸位点的介孔分子筛催化剂Ti-SBA-15-SO3H。采用XRD、FT-IR、Py-IR、BET、EDS等表征手段对该催化剂的表面结构、化学键、酸性位点及酸量、孔道结构、元素分布进行评价，对总酸量进行了测定。以甘油与癸酸酯化合成GMC反应作为探针反应，考察了介孔分子筛催化剂的催化活性。结果表明，Ti的掺入为介孔分子筛提供了Lewis酸位点，引入的磺酸基团增加了介孔分子筛的Bronsted酸位点，同时所制得的Ti-SBA-15-SO3H保留了SBA-15原有表面和孔道结构。该催化剂在反应时间5 h、反应温度150 ℃、甘油与癸酸物质的量比4∶ 1、催化剂用量4%（以总反应物质量计）的条件下，癸酸转化率接近98%，GMC收率达78%以上。该催化剂在循环使用4次之后，GMC收率仍高于70%。制备得到的双酸位分子筛催化剂催化活性高、重复利用性强、热稳定性好，适用于催化合成GMC。 In order to prepare solid acid catalyst with high catalytic activity, strong reusability and good thermal stability for the catalytic synthesis of glycerol monodecanoate（GMC），with tetrabutyl titanate as titanium source and tetraethyl orthosilicate as silicon source, Ti-SBA-15 was synthesized under acidic conditions by soft template method, and sulfonic acid group was introduced by organic grafting. Finally, a mesoporous molecular sieve catalyst Ti-SBA-15-SO3H containing both Bronsted and Lewis acid sites was successfully prepared. The surface structure, chemical bonds, acidic sites and acidity, pore structure and element distribution of the catalyst were characterized by XRD, FT-IR, Py-IR, BET and EDS. The total acidity was determined. The catalytic activity of mesoporous molecular sieve catalysts was investigated by using the esterification of glycerol with capric acid to prepare GMC as a probe reaction.The results showed that Ti doping provided Lewis acid sites for mesoporous molecular sieves, and the introduction of sulfonic acid groups increased the Bronsted acid sites of mesoporous molecular sieves.At the same time, the prepared Ti-SBA-15-SO3H retained the original surface and pore structure of SBA-15. With Ti-SBA-15-SO3H as the catalyst, under the conditions of reaction time 5 h, reaction temperature 150 ℃, molar ratio of glycerol to capric acid 4∶ 1 and catalyst dosage 4% (based on total reactants mass), the conversion rate of capric acid was close to 98%, and the yield of GMC was over 78%. After the catalyst was recycled 4 times, the GMC yield was still higher than 70%.The prepared molecular sieve catalyst with double-acid active sites has high catalytic activity, strong reusability and good thermal stability, and is suitable for the catalytic synthesis of GMC.

With the development of green chemistry, PVC thermal stabilizers should be developed in the direction of non‐toxic, environmental protection, and high efficiency. This study utilized natural Cinnamic acid to successfully synthesize an eco‐friendly and high‐performance cinnamate‐intercalated calcium aluminum hydrotalcite through the coprecipitation method. The structure of CaAl‐cinnamate‐LDHs was analyzed via XRD, IR, SEM, and thermogravimetric analyses. The CaAl‐cinnamate‐LDHs/PVC sample was thoroughly investigated using multiple techniques, including tests, such as oven aging, thermogravimetric analysis, Congo red analysis, and conductivity analysis. Compared with the commercial thermal stabilizers CaSt2/ZnSt2 and CaAl‐CO3‐LDHs, CaAl‐cinnamate‐LDHs demonstrated superior initial whiteness and exceptional long‐term thermal stability, it did not completely blacken until 120 min. Dynamic mechanical analysis showed that the addition of CaAl‐cinnamate‐LDHs could improve the plasticizing performance of PVC. CaAl‐cinnamate‐LDHs also had a synergistic effect with ZnSt2, with a static thermal stabilization time of up to 40.5 min. Through HCl absorption experiments to investigate the thermal stabilization mechanism, the results showed that CaAl‐cinnamate‐LDHs can effectively absorb HCl released during PVC degradation. Highlights: By utilizing natural organic Cinnamic acid, Calcium nitrate, and Aluminum nitrate as raw materials, all from a wide range of sources, the reaction process eliminated the need for toxic solvents and a large number of chemicals.The preparation process of CaAl‐cinnamate‐LDHs was simple and the reaction time was short.Comprehensive tests showcased the exceptional long‐term thermal stability of the CaAl‐cinnamate‐LDHs/PVC sample.The addition of CaAl‐cinnamate‐LDHs can improve the plasticizing property of PVC.The mechanism of CaAl‐cinnamate‐LDHs was capable of absorbing HCl released during PVC degradation. [ABSTRACT FROM AUTHOR]

The iris is a fine structure that controls the amount of light that enters the eye. The ciliary body controls the shape of the lens and produces aqueous humor. The retinal pigment epithelium and choroid (RPE/choroid) are essential in supporting the retina and absorbing light energy that enters the eye. Proteins were extracted from iris, ciliary body, and RPE/choroid tissues of eyes from five individuals and fractionated using SDS-PAGE. After in-gel digestion, peptides were analyzed using LC-MS/MS on an Orbitrap Elite mass spectrometer. In iris, ciliary body, and RPE/choroid, we identified 2959, 2867, and 2755 nonredundant proteins with peptide and protein false-positive rates of

The diverse roles of protein kinase C-δ (PKCδ) in cellular growth, survival, and injury have been attributed to stimulus-specific differences in PKCδ signaling responses. PKCδ exerts membrane-delimited actions in cells activated by agonists that stimulate phosphoinositide hydrolysis. PKCδ is released from membranes as a Tyr(313)-phosphorylated enzyme that displays a high level of lipid-independent activity and altered substrate specificity during oxidative stress. This study identifies an interaction between PKCδ's Tyr(313)-phosphorylated hinge region and its phosphotyrosine-binding C2 domain that controls PKCδ's enzymology indirectly by decreasing phosphorylation in the kinase domain ATP-positioning loop at Ser(359). We show that wild-type (WT) PKCδ displays a strong preference for substrates with serine as the phosphoacceptor residue at the active site when it harbors phosphomimetic or bulky substitutions at Ser(359.) In contrast, PKCδ-S359A displays lipid-independent activity toward substrates with either a serine or threonine as the phosphoacceptor residue. Additional studies in cardiomyocytes show that oxidative stress decreases Ser(359) phosphorylation on native PKCδ and that PKCδ-S359A overexpression increases basal levels of phosphorylation on substrates with both phosphoacceptor site serine and threonine residues. Collectively, these studies identify a C2 domain-pTyr(313) docking interaction that controls ATP-positioning loop phosphorylation as a novel, dynamically regulated, and physiologically relevant structural determinant of PKCδ catalytic activity.

High-resolution 1H nuclear magnetic resonance (1H NMR) was advanced to determine both epoxy value and iodine value (IV) of vegetable oils that occur during their epoxidation. For calibration, rather than using a series of diluted stock samples, epoxidized soybean oils with a range of IV and epoxy value synthesized using entrapped peroxophosphotungstate as the catalyst under different reaction conditions were used. During the epoxidation reaction, IV and epoxy value were tracked with respect to time using 1H NMR and conventional volumetric methods. The integrated peak area of the olefinic hydrogens (5.3–5.5 ppm) was used to calculate the absolute number of double-bonded protons. By comparison of IV obtained by 1H NMR and the traditional Wijs-cyclohexane methods, the correlation coefficient was R2 = 0.9997 for the regression equation y = 1.1314x + 1.0035, where x was the result given by 1H NMR. The average integrated peak areas related to the hydrogens of the epoxide groups located at chemical shifts of 2.9 ppm (monoepoxide) and 3.1 ppm (diepoxide) were used to determine the epoxy value. The quantification of the number of epoxides was carried out by 1H NMR and the values obtained were correlated with epoxide content determined by the hydrochloric acid/acetone method. As a consequence, the correlation coefficient was R2 = 0.9991 for the regression equation y = 0.0052x + 1.7258, where x was the average integrated peak areas related to the hydrogens of the epoxide groups by 1H NMR. The novelty of our study lies in the simultaneous correlation between IV and epoxy value obtained from conventional titrations, the integrated peak area related to olefinic protons, and the average integrated peak area located at the hydrogen of epoxide group, calculated using 1H NMR. This approach is used to monitor and optimize the epoxidation reaction. [ABSTRACT FROM AUTHOR]