N-甘氨酸基马来酰氨酸对聚丙烯成核性的影响

采用N-甘氨酸基马来酰氨酸(GMA）与4A分子筛复合改性聚丙烯（PP）,研究了GMA改性PP(PP-GMA)、GMA和4A分子筛改性PP(PP-GMA-4A)的力学性能。通过差示量热扫描仪、X射线衍射仪及偏光显微镜测试并表征了改性后PP的成核诱导效果及结晶形态。结果表明,改性后PP的结晶温度明显提高,球晶晶粒细化;通过对改性后PP体系的力学性能测试,研究表明,改性后PP的冲击强度、弯曲强度、拉伸强度较纯PP分别提高160 %、47 %、2 %。     

几种N-取代苯基马来酰亚胺单体的合成与表征

以马来酸酐、苯胺及其衍生物为主要原料合成了N-对甲苯基马来酰亚胺(NM PM I)、N-对氯苯基马来酰亚胺(NCLPM I)、N-对甲氧苯基马来酰亚胺(NM OPM I),产率可达85%以上。采用1H-NM R,13C-NM R和FT-IR等仪器对产物及中间产物马来酰胺酸的结构进行详细的表征。研究发现马来酰胺酸和马来酰亚胺苯环上不同的取代基,在1H-NM R谱图中,对HC=CH上质子峰的影响不大,而对苯环上质子峰却有影响,吸(供)电子基使苯环质子的化学位移向低(高)场移动;在13C-NM R谱图中,含强电负性(O、N、C l)的取代基使苯环上δc1低场移动,邻对位δc略向高场移动,取代基的电负性越大,位移也越大。     

N-甘氨酸基马来酰胺酸接枝改性聚丙烯探究

利用马来酸酐和甘氨酸在一定条件下合成了N-甘氨酸基马来酰胺酸（GMA）,并将其熔融接枝到聚丙烯（PP）上。采用X射线衍射（XRD）、差示扫描量热（DSC）和偏光电子显微镜（PLM）等测试手段对聚丙烯的晶体形态及结晶行为进行了考察,并测试了聚丙烯的力学性能和维卡软化点。结果表明：与在纯PP中加入0.15%引发剂DCP、1%助剂苯乙烯和0.3%抗氧剂制的PP/O、PP-g-MAH相比,PP-g-GMA的晶粒较细,结晶温度和结晶度有了提高;力学性能也明显提高;维卡软化点分别提高了18.1℃和15℃。     

N-苄基苦参酰甘氨酸的合成

目的:合成N-苄基苦参酰甘氨酸。方法:以苦参碱为原料,经水解、苄基化、水解等反应得到N-苄基苦参酸,然后利用其结构上的羧基,与甘氨酸甲酯盐酸盐缩合形成N-苄基苦参酰甘氨酸甲酯,再进一步水解生成N-苄基苦参酰甘氨酸。结果与结论:合成得到目标化合物,其结构经MS、IR、1H-NMR等方法确证,产物收率为74.4%(以N-苄基苦参酸计)。     

苯乙烯与N-间甲苯基马来酰亚胺共聚物乳液性能表征

采用种子滴加法合成了苯乙烯与N-间甲苯基马来酰亚胺共聚物乳液,讨论了单体配比对乳液的聚合稳定性、表面张力、流变性、粒径大小及分布、成膜性能的影响。并用DSC和TGA对共聚物耐热性能进行了表征。实验结果表明,随着N-间甲苯基马来酰亚胺含量的增加共聚物的Tg呈明显上升趋势。     

N-(3-甲酰基苯基)甘氨酸衍生物的合成

从苯甲醛和茴香醛出发,分别经过5步反应合成了N-(3-甲酰基苯基)甘氨酸乙酯和N-(2-甲氧基-5-甲酰基苯基)甘氨酸乙酯。对N-(3-甲酰基苯基)甘氨酸乙酯和N-(2-甲氧基-5-甲酰基苯基)甘氨酸乙酯进行乙酰化,然后水解酯基,可分别得N-乙酰基-N-(3-甲酰基苯基)甘氨酸和N-乙酰基-N-(2-甲氧基-5-甲酰基苯基)甘氨酸。这些产物的结构均由1HNMR、13CNMR、HRMS和IR进行了表征。     

合成N-苯基马来酰亚胺的研究

以马来酸酐和苯胺为原料合成N-苯基马来酰亚胺(N-PMI)的过程中，采用对甲苯磺酸和硫酸铜为催化剂，对羟基苯甲醚为阻聚剂，并采用甲苯／二甲基甲酰胺混合溶剂，有效提高了N-苯基马来酰亚胺的产率。加入金属铜盐催化剂后，N-苯基马来酰亚胺的纯度提高到99．4％左右。同时研究了反应物摩尔比、催化剂用量以及混合溶剂配比等因素对合成N-苯基马来酰亚胺的影响。     

单体配比对MMA-CHMI-St和MMA-CHMI-AN悬浮共聚物性能影响的研究

研究了甲基丙烯酸甲酯-N-环己基马来酰亚胺-苯乙烯和甲基丙烯酸甲酯-N-环己基马来酰亚胺-丙烯腈两种三元共聚体系中,单体用量对共聚物玻璃化温度和溶度参数的影响.结果表明,苯乙烯、丙烯腈的加入能提高N-环已基马来酰亚胺的反应活性.共聚物的玻璃化温度随着N-环己基马来酰亚胺用量的增加升高,随着苯乙烯用量的增加先升高后降低,而随着丙烯腈用量的增加降低.共聚物的溶度参数随着N-环己基马来酰亚胺用量的增加增大,而随着苯乙烯、丙烯腈用量的增加降低.     

N-对甲苯基马来酰亚胺(NMPMI)/甲基丙烯酸甲酯(MMA)共聚合研究

根据自由基共聚合和交联改性有机高分子材料的原理,以偶氮二异丁腈(AIBN)为引发剂,甲苯为溶剂,N-对甲苯基马来酰亚胺(NMPMI)和甲基丙烯酸甲酯(MMA)为原料,采用溶液聚合法合成了N-对甲苯基马来酰亚胺/甲基丙烯酸甲酯共聚物,并研究了原料配比、引发剂用量、反应时间、温度等工艺条件对产品收率的影响,确定了共聚合反应...     

N-异丙酸基马来酰亚胺的合成

以马来酸酐（MA）和氨基丙酸（Aln）为原料发生酰胺化反应生成N-异丙酸基马来酰胺酸（A—MA），AMA再在催化剂三乙胺（Et，N）的作用下发生闭环脱水反应生成N-异丙酸基马来酰亚胺（AMI）单体。考察了溶剂、原料配比、催化剂用量、反应温度和反应时间对产品产率的影响。确定了最佳反应条件。并用GG47-FTS7000红外光谱仪、PE-2400有机元素分析仪对产品进行了检测。在最佳反应条件下，所得AMI的总产率达54．1％，纯度达98％，熔点100—101℃。     

Effect of bile acid feeding on hepatic steroid 12 α-hydroxylase activity in hamsters

The effects of feeding cholic acid, chenodeoxycholic acid and ursodeoxycholic acid on the activity of the hepatic steroid 12α-hydroxylase, gallbladder bile acid composition, fecal neutral sterol output, cholesterol synthesis and bile acid synthesis were determined in female hamsters. The 12α-hydroxylase activity was inhibited to 56% by cholic acid, to 62% by chenodeoxycholic acid, and to 78% by ursodeoxycholic acid compared with the control. Bile acid composition was altered by feeding of cholic acid and chenodeoxycholic acid to be rich in the given bile acids. Fecal neutral sterol output increased about twice by feeding chenodeoxycholic acid and ursodeoxycholic acid, whereas cholic acid had no significant effect. Body cholesterol synthesis increased to 217% by chenodeoxycholic acid and to 274% by ursodeoxycholic acid, whereas effect of cholic acid was not significant. Bile acid synthesis was suppressed to 48% of control only by chenodeoxycholic acid. A positive correlation between the 12α-hydroxylase activity and the bile acid synthesis was observed in the control, chenodeoxycholatefed and ursodeoxycholate-fed animals. In conclusion, ursodeoxycholic acid might have less inhibitory effect on the steroid 12α-hydroxylase and the bile acid synthesis than chenodeoxycholic acid.     

铌酸的合成与表征

采用氢氧化钾熔融法以不同无机酸处理合成了铌酸。利用傅立叶变换红外光谱仪,热重分析仪和紫外-可见-近红外光谱仪对合成的铌酸分别进行了表征。结果表明,经冰醋酸处理合成的铌酸纯度较高,用硫酸和硝酸处理合成的铌酸含有少量杂质,而磷酸处理后没有得到铌酸。     

Production of biodiesel from soapstock using an ion-exchange resin catalyst

The feasibility of biodiesel production from soapstock containing high water content and fatty matters by a solid acid catalyst was investigated. Soapstock was converted to high-acid acid oil (HAAO) by the hydrolysis by KOH and the acidulation by sulfuric acid. The acid value of soapstock-HAAO increased to 199.1 mg KOH/g but a large amount of potassium sulfate was produced. To resolve the formation of potassium sulfate, acid oil was extracted from soapstock and was converted to HAAO by using sodium dodecyl benzene sulfonate (SDBS). The maximum acid value of acid oil-HAAO was 194.2 mg KOH/g when the mass ratio of acid oil, sulfuric acid, and water was 10: 4: 10 at 2% of SDBS. In the esterification of HAAO using Amberylst-15, fatty acid methyl ester (FAME) concentration was 91.7 and 81.3% for soapstock and acid oil, respectively. After the distillation, FAME concentration became 98.1% and 96.7% for soapstock and acid oil. The distillation process decreased the total glycerin and the acid value of FAME produced a little.     

双酶连续催化生物合成D-丙氨酸

建立了天冬氨酸消旋酶和D-氨基酸转氨酶双酶连续催化制备D-丙氨酸的方法。利用天冬氨酸消旋酶全细胞催化L-天冬氨酸消旋得到DL-天冬氨酸,离心去除天冬氨酸消旋酶全细胞后升温灭活残留的游离天冬氨酸消旋酶,再加入经镍柱亲和纯化的D-氨基酸转氨酶酶液,催化D-天冬氨酸(D-Asp)和丙酮酸(PA)经转氨反应生成D-丙氨酸。经单因素实验得到天冬氨酸消旋酶最佳催化条件为:反应温度40℃,0.2 mol/L磷酸钾缓冲溶液(pH=7.0),底物L-天冬氨酸质量浓度为100 g/L。D-氨基酸转氨酶最佳催化条件为:反应温度42℃,0.2 mol/L磷酸钾缓冲液(pH=7.0),4 mmol/L磷酸吡哆醛,DL-天冬氨酸质量浓度为50 g/L,底物n(PA)∶n(D-Asp)=1∶10。转化产物经等电点结晶和阳离子树脂分离得到D-丙氨酸。在该条件下,D-天冬氨酸转化率达94%,D-丙氨酸收率为84%,对映体过量值(ee值)=98%。     

稻草酸水解制备乙酰丙酸的研究

以稻草为原料,高压酸水解法制备乙酰丙酸,采用气相色谱法测定水解液中乙酰丙酸的含量,考察了反应温度、反应时间、固液比和硫酸质量分数对乙酰丙酸得率的影响,通过单因素试验确定了最佳水解条件。结果表明,在高压 1.6 MPa 条件下,反应温度 170℃,反应时间 60 min,固液比1:10,硫酸的质量分数为 5% 时,所制得乙酰丙酸得率为 24.35%,此条件下水解残渣中纤维素和多戊糖均已完全反应。     

单体酸组成分析及在润滑添加剂方面的应用

采用GC/MS方法测定了单体酸的主要组成:用甲酯化后的试样进行GC/MS分析,鉴定出肉豆蔻酸(12.16%)、棕榈酸(8.51%)、十八稀酸(25.53%)、硬脂酸(32.72%)等15种物质。从评价铝材轧制油添加剂的性能指标——相容性、润滑性、抗磨性、退火清洁性和抗氧化性5个方面,考察了将单体酸作为或加工成为铝材轧制油添加剂的可行性。     

Pyrophosphatidic acid in mushrooms

The distribution of pyrophosphatidic acid in mushrooms was investigated. Total lipids of mushrooms were extracted from their fruit body, and the pyrophosphatidic acid fraction was isolated by DEAE-silica gel column and silicic acid column chromatography. The presence of pyrophosphatidic acid was tested by thin layer chromatography. Of the 43 species of mushrooms examined, the acid was found in 30. The pyrophosphatidic acid was identified by chromatography, IR spectroscopy and quantitative degradation with aqueous pyridine to produce phosphatidic acid. Chemically synthesized pyrophosphatidic acid was used as standard.     

Differential effects of ursodeoxycholic acid and ursocholic acid on the formation of biliary cholesterol crystals in mice

The preventive effect of 3α,7β,12α-trihydroxy-5β-cholanoic acid (ursocholic acid) and ursodeoxycholic acid on the formation of biliary cholesterol crystals was studied in mice. Cholesterol crystals developed with 80% incidence after feeding for five weeks a lithogenic diet containing 0.5% cholesterol and 0.25% sodium cholate. When 0.25% ursocholic acid or ursodeoxycholic acid was added to the lithogenic diet, the incidence as well as the grade (severity) of the gallstones were reduced. Plasma and liver cholesterol levels were decreased by ursodeoxycholic acid but not by ursocholic acid. Gallbladder cholesterol and phospholipid levels were decreased by both bile acids. The biliary bile acid level was decreased by ursocholic acid but not by ursodeoxycholic acid. After feeding ursocholic acid, its level in the bile was about 25% and the levels of cholic acid and β-muricholic acid decreased. Fecal sterol excretion was not changed by ursocholic acid, but was increased by ursodeoxycholic acid. After feeding ursocholic acid, fecal excretion of deoxycholic acid, cholic acid, and ursocholic acid increased. No differences were found between mice, with or without gallstones, in plasma and liver cholesterol levels, biliary phospholipid and bile acid levels, fecal sterol and bile acid levels, and biliary and fecal bile acid composition. The results suggest that the lower incidence of crystal formation after treatment with ursocholic acid is probably by a different mechanism than with ursodeoxycholic acid. In the mouse model, ursodeoxycholic acid exerts its effect at least partially, by decreasing cholesterol absorption. Ursocholic acid is well absorbed and excreted into bile and transformed into deoxycholic acid by the intestinal microflora in mice.     

不溶性腐殖酸吸附Cr(Ⅵ)的研究

研究了不溶性腐殖酸对六价铬的吸附作用。进行了反应接触时间、pH值、IHA投加量、光照条件、温度等对反应的影响研究,确定了最佳反应条件,同时应用未处理的腐殖酸进行对比研究,说明不溶性腐殖酸的作用效果。试验表明在反应接触时间60 min、pH值为7左右、不溶性腐殖酸投加量为5 g/L和Cr(Ⅵ)的质量浓度为5.36 mg/L的条件下,不溶性腐殖酸对铬离子去除可达95%,比未处理的腐殖酸对铬离子去除提高近1倍。并绘制了不溶性腐殖酸对铬离子的反应动力学曲线和吸附等温线。