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1.
以亚油酸甲酯为原料,Se O2为催化剂,设计并合成了4个羟基亚油酸异构体——13-羟基-9Z,11E-十八碳二烯酸甲酯,13-羟基-9E,11E-十八碳二烯酸甲酯,9-羟基-10E,12Z-十八碳二烯酸甲酯和9-羟基-10E,12E-十八碳二烯酸甲酯,其结构经1H NMR,13C NMR和LC-MS确证。  相似文献   

2.
原位沉析法制备碳酸钙/壳聚糖三维复合材料的研究   总被引:6,自引:0,他引:6  
将含有Ca2+的壳聚糖溶液与含有CO2-3的碱溶液用离子可渗透膜隔离,根据膜渗透原理,使膜内壳聚糖与碱液原位沉析,生成碳酸钙,得到具有高强度的碳酸钙(CaCO3)/壳聚糖(CS) 三维复合材料. XRD测试结果表明,生成的碳酸钙以方解石晶型存在. 从SEM可以观察到碳酸钙颗粒尺寸约为5~10 μm,并且颗粒呈有序分布,它们以棒材的纵轴为中心,围绕中心呈环状分布. 对不同碳酸钙含量的复合棒材进行了弯曲性能测试,其弯曲强度随碳酸钙含量的增大先上升后下降. 在碳酸钙质量分数为10%时,弯曲强度达到最大值(约为113 MPa),弯曲模量为2.6 GPa.  相似文献   

3.
气相色谱-质谱测定樟林番荔枝种子挥发油的脂肪酸组成   总被引:1,自引:0,他引:1  
用溶剂萃取法提取樟林番荔枝果实种子中的挥发性物质,测定出其挥发油质量分数为13.3%;利用GC-MS方法分离确认出其中的9种化学成分;用面积归一化法得出了9种脂肪酸在挥发油中的质量分数;其中9-十八烯酸占49.42%,十六酸占20.37%,十八酸占14.16%,9,2-十八二烯酸占13.59%;不饱和脂肪酸,占63.01%.该项研究给番荔枝果实的深入开发利用及种质资源的有效保护提供了科学依据.  相似文献   

4.
宋文东  王浩  张夏娟 《分析试验室》2007,26(Z1):353-356
采用气相色谱-质谱联用分析法,分析测定了红树植物桐花树AegicerasCorniculatum叶子中挥发油和脂肪酸的成分.结果表明:挥发油中分离出24个峰,鉴定出8种化合物,2,6-二叔丁基-4-甲基苯酚含量丰富,占挥发油总量的20.60%;脂肪酸中分离出16个峰,鉴定出10种脂肪酸,其中主要成分有十六酸(棕榈酸,16.17%)、9,12-十八碳二烯酸(亚油酸,25.73%)、9-十八碳烯酸(油酸,41.52%)等.  相似文献   

5.
邵林军  吴健  徐志康 《高分子学报》2010,(11):1283-1287
以单氨基卟啉作为引发剂,引发L-谷氨酸-γ-十八烷酯N-羧基内酸酐(SLGNCA)开环聚合合成卟啉化聚(L-谷氨酸-γ-十八烷酯)(PSLG),进一步通过静电纺丝制备其纤维膜.相比于自由氨基卟啉,金属氨基卟啉尤其是钴氨基卟啉引发得到的PSLG具有更高的分子量.紫外-可见光谱和荧光光谱研究表明,卟啉化PSLG依然具有卟啉独特的光谱性能,静电纺后可以制备具有均匀红色荧光的微米级纤维.  相似文献   

6.
利用X射线吸收精细结构光谱(XANES)研究了过碱硫化烷基酚钙与二烷基二硫代磷酸锌(ZDDP)复配使用时对ZDDP形成摩擦膜的表面化学行为的影响, 并提出了其和ZDDP的相互作用机制. 结果表明, 在ZDDP中加入过碱硫化烷基酚钙后完全改变了ZDDP单独使用时形成摩擦膜的结构, 摩擦膜中含有一定数量的钙离子, 其结构以磷酸钙为主; 对较高碱值的过碱硫化烷基酚钙, 在高浓度下使用时, 在摩擦膜形成的同时观测到碳酸钙颗粒的沉积. 此外, ZDDP和过碱硫化烷基酚钙共同使用时形成的摩擦膜厚度减小. 摩擦膜特性的改变是ZDDP和过碱硫化烷基酚钙复配体系抗磨性能变差的主要原因.  相似文献   

7.
采用索氏提取法提取油松籽中的油脂,得油率为42.9%;对油脂进行甲酯化处理后用气相色谱-质谱联用仪检测其中的脂肪酸组成及含量。实验结果表明,油松籽油中含有7种脂肪酸,分别为肉豆蔻酸10.38%、硬脂酸3.05%、油酸21.98%、亚油酸(13,16-十八碳二烯酸)3.53%、亚油酸(9,12-十八碳二烯酸)38.38%、亚麻酸20.06%和二十碳三烯酸2.62%,其中饱和脂肪酸含量为13%,不饱和脂肪酸含量为87%。  相似文献   

8.
超临界萃取蝼蛄脂肪酸成分及其气相色谱-质谱分析   总被引:1,自引:0,他引:1  
郭澄  魏道智 《分析化学》2006,34(Z1):15-18
采用超临界CO2萃取蝼蛄总脂肪酸,对影响萃取效果的各个因素应用正交设计试验,优化了各萃取参数.各个因素的影响顺序为压力>温度>时间>流量.萃取的优化条件为压力35 MPa,温度50℃,时间1 h,流量45 kg/h.运用该萃取条件改善了萃取物的物理性状,脂肪酸的纯度提高,总脂肪酸的含量可达83.29%;而采用常规的有机溶剂提取法,脂肪酸的纯度仅为60%左右.甲酯化采用气相色谱-质谱分析技术对其中的16个成分进行了鉴定,并测定了相对含量,其中主要有油酸甲酯(30.40%)、十六烷酸甲酯(14.19%)、9,12-十八碳二烯酸甲酯(11.99%)、油酸乙酯(11.75%)、9-十六碳烯酸甲酯(7.77%)、十六烷酸乙酯(5.97%)、9,12-十八碳二烯酸乙酯(4.53%)及9-十六碳烯酸乙酯(2.87%)等.  相似文献   

9.
本文叙述了可溶性滤膜富集分光光度法测定粮食中微量元素铁的简便方法.在pH4.7的醋酸-醋酸钠缓冲溶液中,铁(Ⅱ)与邻二氮菲、十二烷基苯磺酸钠形成络合物,该络合物被硝化纤维微孔滤膜定量富集,富集膜能溶解在小体积的乙二醇独甲醚中,于510 nm处以空白试剂为参比测定吸光度,可提高测定的灵敏度.  相似文献   

10.
采用静电纺丝法制备了丙烯腈/丙烯酸共聚物(PANCAA)纳米纤维膜,研究了纺丝液浓度对纤维形态的影响,以扫描电子显微镜观察纤维形貌,遴选得到最佳纺丝条件.以1-乙基-3-(N,N-二甲基氨基丙基)碳二亚胺/N-羟基丁二酰亚胺(EDC/NHS)为偶联剂,在纤维膜表面引入壳聚糖修饰层,采用衰减全反射傅里叶变换红外光谱(ATR/FTTIR)、水接触角和称重法考察了修饰前后膜的变化.通过戊二醛将过氧化氢酶固定到壳聚糖修饰的PANCAA纳米纤维膜上,研究了壳聚糖及戊二醛浓度对固定化过氧化氢酶的影响,结果表明,在壳聚糖浓度为25 mg/mL及戊二醛质量分数为5%条件下,壳聚糖修饰膜的固定化酶活性比空白膜提高了41.7%,稳定性也得到了不同程度的提高.  相似文献   

11.
本文以丁二酸酐(SAA)、2-羟基-4-(2-羟基乙氧基)-2-甲基苯丙酮(D2959)和环氧油酸(EOA)为原料,合成了一种具有感光性的脂肪酸S-2-E,并用于碳酸钙的改性.然后以油酸(OA)改性碳酸钙为对比,通过吸油量测试、差动光照热分析仪(DPC)、动态力学分析(DMA)、扫描电镜(SEM)等测试手段讨论了S-2-E对碳酸钙的改性效果、相应改性碳酸钙S-2-E-CaCO3的光活性及S-2-E-CaCO3对UV涂料的性能影响.结果显示,S-2-E对碳酸钙的改性效果与OA相当.碳酸钙经S-2-E改性后具有一定的光活性,能参与UV涂料的固化,固化膜的硬度、耐水性等性能有所改善.  相似文献   

12.
碳酸钙的原位合成及表面改性   总被引:3,自引:0,他引:3  
利用碳化法, 选用几种常见的改性剂(硬脂酸钠、十八碳醇磷酸酯和油酸)对碳酸钙进行了原位合成及表面改性. 通过活化度、白度、接触角的测定, 对比了其改性效果, 同时通过傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)、透射电镜(TEM)等测试手段对产品进行表征. FT-IR结果表明, 改性剂与碳酸钙表面是以化学键合和物理吸附方式相结合. 碳酸钙改性后, 其红外υ3特征吸收峰出现约44 cm-1的蓝移现象. 对反应机理进行了初步探讨. 实验结果表明, 当十八碳醇磷酸酯用量达到2%(以碳酸钙的质量分数计)时, 产品活化度达到99.9%, 白度值达到97.3%, 接触角达到了122.25°, 从而为新型无机填料的制备提供了理论依据和合成手段.  相似文献   

13.
Hierarchically structured CaCO(3) films were synthesized at atmospheric conditions (room temperature and 1 atm) without the use of templates or amphiphilic molecules in this process. The resulting CaCO(3) film was formed by self-organization between Ca(OH)(2) and aqueous CO(2). The building blocks of the CaCO(3) film were thought to be CaCO(3) primary nanoparticles that aligned to build higher level structures with greater size, called mesocrystals, depending on the additives. The soluble additives played a key role in the control of the morphology, crystallinity, and polymorphism of the CaCO(3) film, and the effects strongly depended on the type of additive and their concentrations. The additives used in this study decreased the crystallinity of CaCO(3) (calcite) film in the order of glucose > aspartic acid > serine in a manner inversely proportional to the concentration of the additives. In addition, Mg(2+), K(+), and Na(+) ion additives led to the formation of an aragonite phase, the proportion of which increased with the concentration of ions. The threshold concentrations of these ions for the formation of the aragonite phase in CaCO(3) film were found to be in the order of Na(+) > K(+) > Mg(2+).  相似文献   

14.
采用阳极电化学氧化在铝片表面制备出表面含有氧化铝膜的铝片(AAO/Al), 分别用FTIR-ATR技术和密闭间歇式反应装置考察了该样片对油酸和乙烯的光解作用, 结合UV-DRS和FTIR表征结果对薄膜在油酸和乙烯光解中的作用进行了探讨. 结果表明:AAO/Al能够吸收小于265 nm的紫外光, 而无AAO膜的铝片对波长大于220 nm的紫外光没有任何吸收;254 nm紫外光照射下AAO/Al对油酸和乙烯的光解具有明显的促进作用, 光照3 h油酸的分解率达到70%, 乙烯也有9%的分解, 但相同条件下在无AAO膜的铝片上, 油酸的光解率仅为30%, 乙烯几乎不分解;然而, 在365 nm紫外光照射下, AAO/Al同纯铝片一样对两反应物的光解都没有任何促进作用. 分析认为, AAO膜能吸收254 nm的紫外光和对有机物分解具有光催化作用的可能原因是在AAO膜结构中存在过量的Al原子和氧空位.  相似文献   

15.
A micropatterned multilayer film, which was fabricated from layer-by-layer electrostatic self-assembly of nitrodiazoresin (NDR)/poly(acrylic acid) (PAA) followed by photolithography, was utilized as a structured template for the biomimetic mineralization of calcium carbonate. Micropatterned CaCO3 films consisting of regularly aligned calcite crystals oriented in the <104> direction were selectively deposited on the patterned NDR/PAA multilayer film.  相似文献   

16.
Modified calcium carbonate (CaCO3) nanoparticles with cubic- and spindle-like configuration were synthesized in situ by the typical bobbling (gas-liquid-solid) method. The modifiers, such as sodium stearate, octadecyl dihydrogen phosphate (ODP) and oleic acid (OA), were used to obtain hydrophobic nanoparticles. The different modification effects of the modifiers were investigated by measuring the active ratio, whiteness and the contact angle. Moreover, transmission electron microscopy (TEM), X-ray diffracti...  相似文献   

17.
纳米/微米碳酸钙的结构表征和热分解行为   总被引:10,自引:0,他引:10  
采用棕榈酸对纳米碳酸钙进行有机表面改性, 运用SEM﹑TEM、XRD、FTIR 及TG-DTG 对表面改性前后的纳米碳酸钙进行表征, 并与微米碳酸钙的微晶结构及热分解特性进行比较. FTIR 分析结果确证了棕榈酸与纳米碳酸钙表面是以化学键合和物理吸附方式相结合, 粒子表面存在羧基等有机官能团的红外吸收特征. 对比研究发现, 碳酸钙微晶纳米化后, 其红外V3特征吸收峰出现约35 cm-1 的蓝移现象, 并且明显窄化. 初步解释了纳米碳酸钙红外吸收峰蓝移的原因, 认为尺寸效应和晶体场效应是影响纳米碳酸钙红外光谱特征的主要因素. 微晶结构的变化使得纳米碳酸钙的热分解反应表现出反常特性, 热分解温度较微米碳酸钙下降了40.6 ℃.  相似文献   

18.
The effects of seven carboxylic acids, i.e., acrylic acid, maleic acid, tartaric acid, malic acid, succinic acid, and citric acid, on CaCO(3) crystallization were studied using the unseeded pH-drift method along with a light-scattering technique. Experiments were started by mixing solutions of CaCl(2) and NaHCO(3) in the presence or absence of additives. The crystallization was studied by recording the decrease in pH resulting from the reaction Ca(2+)+HCO(3)(-)-->CaCO(3)+H(+). A given amount of carboxylic acid was added to the solution of CaCl(2) or NaHCO(3) before mixing the reactants. The pH profiles obtained in the case of the CaCl(2) solution containing an additive were similar to those for the NaHCO(3) solution containing one, and when an additive was added after the onset of crystallization, the growth of CaCO(3) immediately stopped. The light-scattering observations, in all cases, indicated that CaCO(3) nucleation occurred at 10-20 s after mixing of the reactants. The results indicated that the nucleation of CaCO(3) was not influenced by the presence of carboxylic acids, but CaCO(3) crystal growth was reduced by their adsorption to the surface of the CaCO(3) crystals. These phenomena were explained by assuming a stronger affinity of the carboxylic acids for CaCO(3) particles than for the free Ca(2+) ions in solution. The crystallization of CaCO(3) in the presence of additives was divided into three stages: nucleation, growth incubation, and growth periods. Copyright 2001 Academic Press.  相似文献   

19.
蒋伏广  姚晋荣  陈新  邵正中 《化学学报》2009,67(14):1675-1679
详细研究了不同浓度的聚丙烯酸(分子量为2000, PAA-2k)和镁离子对碳酸钙在再生丝素蛋白(RSF)膜表面结晶的影响. 发现单独采用PAA-2k时, 碳酸钙主要以方解石形式在RSF膜表面沉积成膜; 若加入一定量的镁离子参与共同调控, 碳酸钙则有可能在RSF膜表面形成以文石为主的连续薄膜, 进而得到了具有类珍珠质结构的层状RSF/文石复合材料. 我们认为, 吸附在RSF膜表面的PAA对碳酸钙成核诱导作用及其溶液中PAA对碳酸钙结晶抑制作用共同导致RSF膜表面碳酸钙薄膜的形成.  相似文献   

20.
The normal and friction forces between layers of three fatty acids (stearic, oleic, and linoleic acid) and a rosin acid (dehydroabietic acid) have been measured in n-hexadecane with a surface forces apparatus. Stearic, oleic, and dehydroabietic acid form loose-packed monolayers on mica surfaces when adsorbed from dry n-hexadecane. Linoleic acid forms an additional dimer layer between monolayer-covered surfaces, where it is stabilized by interactions between the double-bond-rich regions of the molecules. The monolayers formed by linoleic and dehydroabietic acid are thinner than the ones formed by stearic and oleic acid, but are not as easily removed from between the mica surfaces when the load or pressure is increased. The friction force increased linearly with load in all systems, and the friction coefficient increased with increasing unsaturation. Linoleic acid showed two regimes of linear friction with increasing load, corresponding to two different film thicknesses. Its friction was sensitive to sliding speed and adsorption time, and the thinner film observed at higher load had a lower friction coefficient. Such features were not observed for stearic and oleic acid, where the monolayers were removed and the friction coefficient changed to that of pure n-hexadecane at a pressure of 3.5 MPa.  相似文献   

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