Two New Phenolic Carboxylic Acid Esters from Opuntia vulgaris

Two new phenolic carboxylic acid esters n-butyl eucomate(1) and methyl eucomate (2) and six known compounds eucomic acid(3), 3-β-acetyl-taraxerol (4), friedelin(5),lupenone(6),methyl linoleate(7) and methyl oleate(8) were isolated from the stems of Opuntia vulgaris Mill(Cactaceae). Their structures were determined on the basis of spectral methods. Compounds 3,4,6,7,8 were isolated for the first time from this plant.

Nickel(II)-Catalyzed Reductive Coupling of Xanthate Esters with Sulfur-Containing and Selenium-Containing Compounds:Synthesis of Unsymmetric Sulfides and Selenides

Unsymmetric sulfides and selenides have great applications in the pharmaceutical field.Herein,we describe the reductive coupling reaction of xanthate esters with sulfur-containing and selenium-containing compounds(thio(seleno)sulfonates and disulfides(selenides))under the nickel-catalyzed condition.It provides a mild and effective method for the synthesis of unsymmetric sulfides and selenides which has the advantages of mild reaction conditions,high yields and a wide range of substrates.

Curing mechanism of alkaline phenolic resin with organic ester

To study the curing mechanism of alkaline phenolic resin with organic ester, three esters were chosen to react with three systems - alkaline phenolic resin, potassium hydroxide aqueous solution containing phenol, and potassium hydroxide aqueous solution. The variations of pH, heat release and gel pH during the reactions were monitored and measured. Infrared spectroscopy （IR） and thermal gravity analysis （TG） techniques were used to characterize the curing reaction. It was found that organic ester is only partial y hydrolyzed and resin can be cured through organic ester hydrolysis process as wel as the reaction with redundant organic ester. The sequential curing mechanism of alkaline phenolic resin cured by organic ester was identified as fol ows： a portion of organic ester is firstly hydrolyzed owing to the effect of the strong alkaline; the gel is then formed after the pH decreases to about 10.8-10.88, meanwhile, the redundant organic ester （i.e. non-hydrolysis ester） starts the curing reaction with the resin. It has also been found that the curing rate depends on the hydrolysis velocity of organic ester. The faster the hydrolysis speed of the ester, the faster the curing rate of the resin.

Application conditions for ester cured alkaline phenolic resin sand

Five organic esters with different curing speeds:propylene carbonate(i.e.high-speed ester A);1,4-butyrolactone;glycerol triacetate(i.e.medium-speed ester B);glycerol diacetate;dibasic ester(DBE)(i.e.lowspeed ester C),were chosen to react with alkaline phenolic resin to analyze the application conditions of ester cured alkaline phenolic resin.The relationships between the curing performances of the resin(including pH value,gel pH value,gel time of resin solution,heat release rate of the curing reaction and tensile strength of the resin sand)and the amount of added organic ester and curing temperature were investigated.The results indicated the following:(1)The optimal added amount of organic ester should be 25 wt.%-30 wt.%of alkaline phenolic resin and it must be above 20 wt.%-50 wt.%of the organic ester hydrolysis amount.(2)High-speed ester A(propylene carbonate)has a higher curing speed than 1,4-butyrolactone,and they were both used as high-speed esters.Glycerol diacetate is not a high-speed ester in alkaline phenolic resin although it was used as a high-speed ester in ester cured sodium silicate sand;glycerol diacetate and glycerol triacetate can be used as medium-speed esters in alkaline phenolic resin.(3)High-speed ester A,medium-speed ester B(glycerol triacetate)and low-speed ester C(dibasic ester,i.e.,DBE)should be used below 15°C,35°C and 50°C,respectively.High-speed ester A or lowspeed ester C should not be used alone but mixed with medium-speed ester B to improve the strength of the resin sand.(4)There should be a suitable solid content(generally 45 wt.%-65 wt.%of resin),alkali content(generally 10 wt.%-15 wt.%of resin)and viscosity of alkaline phenolic resin(generally 50-300 mPa·s)in the preparation of alkaline phenolic resin.Finally,the technique conditions of alkaline phenolic resin preparation and the application principles of organic ester were discussed.

聚丙烯餐盒复用过程中邻苯二甲酸酯类塑化剂和合成酚类抗氧化剂的检测及迁移规律研究

目的建立气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)同时测定聚丙烯(polypropylene,PP)餐盒中邻苯二甲酸酯类塑化剂和合成酚类抗氧化剂含量的分析方法,并研究其在复用过程中向酸性食品模拟物(4%乙酸)、非酸性食品模拟物(10%乙醇、水)以及油脂类食品模拟物(异辛烷、橄榄油)的迁移量。方法PP餐盒经正己烷超声提取,食品模拟物根据其不同的性质选择不同萃取液,液液萃取辅以超声提取,经SH-Rxi-5MS(30 m×0.25 mm,0.25μm)石英毛细管柱分离,单离子监测(single ion monitoring,SIM)模式扫描,外标法定量。结果20种化合物的线性关系在0.01~1.00mg/L范围内表现良好,其相关系数均大于0.99,检出限和定量限分别是0.01~0.02 mg/L和0.03~0.06 mg/L。5种食品模拟物在0.05、0.10和0.50 mg/L3个水平下加标回收率为80.4%~108.4%,相对标准偏差为1.3%~10.6%(n=6)。结论该方法实验过程简便,灵敏度、精密度、回收率高,适用于PP餐盒中邻苯二甲酸酯类塑化剂和合成酚类抗氧化剂含量和迁移量的测定。实验结果可知,PP餐盒在热接触和微波加热的复用过程中均有一定程度的迁移,需要引起重视。

固相萃取-气相色谱-串联质谱技术测定船用残渣燃料油中酚类及脂肪酸甲酯类化合物

本文利用乙酸银修饰的氧化铝-硅胶材料制备固相萃取柱对船用残渣燃料油样品进行净化分离,结合气相色谱-串联质谱技术,使用DB-35 MS UI色谱柱分离,多反应监控模式,内标法定量测定酚类及脂肪酸甲酯(FAME)类化合物。对影响酚类和FAME类化合物的进样方式、萃取溶剂的选择、固相萃取柱类型的选择以及淋洗和洗脱条件进行了优化,建立了船用残渣燃料油中酚类及FAME类化合物的测定方法。方法在浓度0.05~2.5μg/mL范围线性良好,具有检出限(0.1~1.2 mg/kg)和定量限(0.3~4.0 mg/kg)低,稳定性好和萃取效率高,以及基质效应不显著等优势。通过用不含目标物的空白燃料油配制0.10、0.50、2.50 mg/L浓度水平的试样考察方法的可靠性,获得满意的回收率(85.5%~115.4%)和相对标准偏差(RSD≤6.2%)。实验结果表明,建立的方法可实现船用残渣燃料油中酚类及FAME类化合物的有效检测。另外,劣质船用燃油存在不少的酚类和FAME类物质,高浓度苯酚、甲酚、二甲酚、对枯基苯酚、脂肪酸甲酯等物质可能是导致船舶油泵损坏的重要原因。

酯硬化水玻璃砂+酯硬化碱酚醛树脂砂“双砂”造型技术创新与实践

针对公司新上马的酯硬化水玻璃砂铸钢造型生产线初始的酯硬化水玻璃砂造型工艺生产部分厚大合金钢、低碳合金钢及高锰钢铸件表面存在的气孔、皱皮、气痕、冷隔和粘砂铸造缺陷,在原湿型水玻璃砂面、背砂工艺生产铸钢件的启发下,在新上马的酯硬化水玻璃砂铸钢造型生产线通过实施“酯硬化碱酚醛树脂砂面砂+酯硬化水玻璃砂背砂”“双砂”造型的工艺创新,较好地解决了初始酯硬化水玻璃“单一砂”造型工艺生产厚大铸钢件存在的问题,发挥了酯硬化水玻璃砂与酯硬化碱酚醛树脂砂两种型砂各自的工艺优势,为公司新上马的酯硬化水玻璃砂铸钢造型生产线提升铸件质量奠定了坚实的基础。

Sorption and desorption kinetics of phthalates and phenol on water/sediment interface

The sorption and desorption kinetics of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP) and phenol on water and sediment interface were studied using two compartment model in this paper. The results showed that the sorption coefficients of DMP, DEP, DBP and phenol measured by batch equilibrium method were 16.79, 24.55, 132 and 0.65μg 1-1/n · g -1 · ml -1/n , the sorption and desorption kinetic constants of DMP, DEP, DBP, phenol were 0.0248, 0.0357, 0.0727, 0.014ml·cm -2 ·h -1 and 0.000512, 0.000754, 0.00127, 0 000899h -1 at static condition respectively; and the sorption and desorption kinetics constants of above chemicals were 0 279, 0.382, 0.496, 0.0904ml·cm -2 ·h -1 and 0.0442, 0.0031, 0.00116, 0.00247h -1 at flow water condition respectively.

Phenolic Acid Content and Free Radical-Scavenging Activity of Two Differently Processed Carob Tree(Ceratonia siliqua L.)Pod

The phenolic acids in free phenolic acid (FPHA), methanol-soluble phenolic ester (MSPE), and methanol-soluble phenolic glycoside (MSPG) fractions of two carob products, natural carob-pod flour (CPF) and commercial carob-pod flour (CCPF), were identified and quantified using high-performance liquid chromatography-mass spectrometry (HPLC-MS). Six phenolic acids were identified in the carob flours (gallic acid, protocatechuic acid, gentisic acid, syringic acid, p- coumaric acid, and sinapic acid). Gallic acid was the major phenolic acid;and its concentrations in CCPF were substantially higher than in CPF (135 - 166 and 85.2 - 91.3 mg/g dw, respectively). The concentrations of p-coumaric acid and sinapic acid were also higher in CCPF than in CPF. In contrast, the concentrations of protocatechuic acid and gentisic acid were generally lower in CCPF than in CPF, with the only exception being gentisic acid glycosides. Both carob-pod flours contained almost the same amount of sinapic acid and syringic acid. The total phenolic contents of the FPHA, MSPE, and MSPG fractions of CPF were found to be 44%, 38%, and 69% that of the respective fractions of CCPF. Correspondingly, the FPHA, MSPE, and MSPG fractions of CCPF had higher free radical-scavenging activity (28.4%, 33.1%, and 26.2%, respectively) than the corresponding fractions of CPF (9.2%, 28.0%, and 9.2%, respectively). Notably, the FPHA and MSPG fractions of each sample had very similar scavenging activity while the MSPE fraction always had higher activity. The FPHA and MSPG fractions of CPF had the lowest activities.

Dielectric Relaxation of Methyl Methacrylate and Ethyl Methacrylate on Complexation with Phenols

Dielectric absorption studies of H-bonded complexes of methyl methacrylate (MMA) and ethyl methacrylate (EMA) with p-cresol, p-chlorophenol, 2,4-dichlorophenol, and p-bromophenol were studied at microwave frequency 9.37 GHz in dilute solution of carbon tetrachloride at 308 K. Different dielectric parameters like dielectric constantε′ and dielectric loss ε″ at microwave frequency, static dielectric constant ε_0 and dielectric constant ε_∞ at optical frequency were determined. The validity of the single frequency equation of Higasi et al. for multiple relaxation time τ_(1) was found to be a function of the hydrogen bonding strength of phenolic hydrogen, whereas the group rotation relaxation time τ_(2) was a function of the steric interaction of proton donor. The relaxation time was the maximum at 50∶50 (molar ratio) of methacrylates with phenols.

酯硬化改性碱酚醛树脂砂的工艺试验及“铸钢+铸铁+铸铝”“三合一”柔性铸造生产实践

通过对酯硬化改性碱酚醛树脂砂的机理分析和相关理化性能检测,摸索工艺特性,经过工艺试验获得了工艺配方,并对铸钢件进行了工艺试制和批量生产,在试验取得了良好技术效果的基础上,扩展到了铸铁(球墨铸铁)件和铸铝件的工艺试制和生产。工艺验证和生产实践表明:酯硬化改性碱酚醛树脂砂工艺适应性强,能够满足铸钢、铸铁和铸铝的生产工艺要求,实现了同一种型砂工艺和同一条生产线(单元)既生产铸钢、又生产铸铁和铸铝的“三合一”酯硬化改性碱酚醛树脂砂创新工艺,解决了过去公司铸钢、铸铁、铸铝多种型砂工艺交织在一起存在的各种问题,为公司高质量发展奠定了坚实的基础。

存放时间对酯固化碱性酚醛树脂自硬砂性能的影响

以铸造生产中常用的酯固化碱性酚醛树脂自硬砂(碱酚醛树脂砂)为研究对象,研究在生产现场存放时间对酯固化碱酚醛树脂砂室温抗拉强度、发气量等性能的影响。结果表明,在生产现场存放29天的过程中,碱酚醛树脂砂试块的室温抗拉强度先上升后下降,发气量未出现明显的上升,最低室温抗拉强度为0.72 MPa,最高发气量为11.1 mL/g,均满足铸件生产要求。

成熟期对冬枣多酚含量及其抗氧化活性的影响

研究了全绿、绿白、半红和全红四个成熟期冬枣果实的果皮和果肉中游离态、酯化态和结合态的酚含量以及其总抗氧化能力、清除DPPH自由基和铁还原能力的变化。结果表明,冬枣果实酚类物质主要以游离态和酯化态形式存在于果皮当中,全红期果皮以结合态为主。冬枣果皮中游离态和酯化态酚类物质对总抗氧化能力、清除DPPH自由基和铁还原能力起主要作用。半红期冬枣果实酚含量最多以及其抗氧化活性最为突出。

高效液相色谱测定不同成熟期枣皮酚类物质

为进一步探讨成熟过程中酚类物质在枣果皮中的组成及分布情况,以冬枣为实验材料,利用高效液相色谱法分别对全绿、绿白、半红和全红4个成熟期的果皮中游离态、酯化态和结合态多酚进行了定性定量检测分析。色谱分析条件:色谱柱为Waters C18柱,流动相A泵为1%醋酸水、B泵为1%醋酸甲醇,总流速为0.8mL/min,柱温30℃,进样量10μL,检测波长280nm。结果表明:4个成熟期的冬枣果皮多酚都含有儿茶素、表儿茶素和香豆酸,并且儿茶素和表儿茶素主要以游离态和酯化态形式存在,而香豆酸在4个成熟期主要以酯化态和结合态形式存在。

真空辅助RTM成型技术应用及适用树脂体系

简要介绍了真空辅助RTM技术(VARTM)对其所需树脂体系的基本要求,该技术在国内外的应用情况,并对适用于该技术的树脂体系进行综述。

二苯胺合成新工艺研究

采用磷酸芳基酯催化苯胺与苯酚合成二苯胺的新工艺，探讨了合成反应条件对二苯胺收率的影响规律。在ＨＤ９５－２用量８％，苯胺与苯酚摩尔比２∶１及反应温度３６０℃，反应时间１４ｈ的优化工艺条件下，二苯胺的收率达到５５％以上。

T-50石油酯含酚废水的治理及资源化

采用ＣＨＡ－１１１大孔吸附树脂固定床，处理Ｔ－５０石油酯生产中高浓度含酚废水。经树脂吸附处理，酚总去除率＞９９．９％，ＣＯＤ去除率＞９５％，出水中酚浓度＜５ｍｇ／Ｌ；再经次氯酸钠氧化二级处理，实现了出水达标排放和废水中酚的富集、回收与资源化。

改进的酚-溴化氰法合成酚醛型氰酸酯及其表征

采用改进的酚-溴化氰法合成了酚醛型氰酸酯单体树脂,并用红外、凝胶实验及热失重分析(TGA)对其进行了结构和性能的表征。与传统的酚-溴化氰法相比,改进的酚-溴化氰法得到了性能稳定的合成产物,该产物在200℃时的凝胶时间为6 5min,在凝胶时无冒烟、发黑现象,固化树脂在800℃时氮气氛下的残碳率为63 6%。

4-肉桂酰阿魏酸苯酚酯衍生物的合成及其抗炎活性

选择对环氧酶／５－脂氧酶和氧自由基具有抑制作用的苯乙烯酚作为先导物，设计合成了１２个４－肉桂酰阿魏酸苯酚酯目标物，其中８个化合物未见文献报道．经药理初筛结果表明，目标物（７ｇ）对角叉菜胶致大鼠足趾肿胀，二甲苯致小鼠耳廓肿胀和棉球致大鼠肉芽组织增殖有显著抑制作用．

季戊四醇螺环磷酸苯酚酯的合成及结构表征

以水作溶剂,季戊四醇螺环磷酰二氯与苯酚在碱性条件下反应,得到季戊四醇螺环磷酸苯酚酯。用反应体系中的苯酚钠在269.6 nm处的吸光度变化跟踪反应进程,确定反应时间。用IR1、H NMR以及磷元素分析测试技术表征了产品结构。用TG法分析了产品的热稳定性。