Synthesis of mesoporous alumina by using a cost-effective template

A salt of stearic acid, i.e., magnesium stearate [(C₁₇H₃₅COO)₂Mg], can be used as a chemical template for the formation of mesoporous alumina, and is a less expensive reagent than stearic acid. Mesoporous alumina prepared using this cost-effective surfactant shows similar pore properties with respect to pore size (3.5 nm) and surface area (above 300 m²Vg) to that prepared using stearic acid. In addition, textural porosity, arising from non-crystalline intraaggregate voids and spaces, was effectively removed by the addition of magnesium nitrate. The entire transformation from aluminum hydroxide to active alumina was performed at 550 °C, and the crystallinity of the product was confirmed by powder XRD analysis.²⁷A1 MAS NMR result shows the phase of mesoporous alumina is the γ-alumina form.     

Combination of the Elevated Stearic Acid Trait with Other Fatty Acid Traits in Soybean

Stearic acid is one of five major fatty acids found in soybean oil. It is a fully saturated lipid and is known for neutral or positive effects on LDL cholesterol when consumed by humans. Unfortunately, stearic acid only accounts for about 4% of the total seed oil produced in commodity soybean. Previous work has shown that stearic acid can reach levels as high as 28% of the total oil fraction when the SACPD-C gene, encoding the delta-9-stearoyl-acyl carrier protein desaturase responsible for most of the stearic acid variation in soybean seed, is ablated in combination with other loci. In order to increase stearic acid content and create soybeans with improved utility based on fatty acid composition, we combined mutations in SACPD-C with other mutations in the fatty acid biosynthetic pathway. Soybean plants carrying mutant alleles of both SACPD-C and FAD2-1A produce seed with stearic acid levels from 14% to 21%, and with elevated levels of oleic acid. Soybeans carrying mutations in both SACPD-C and FAD3A or FAD3C have both statistically significantly elevated levels of stearic acid (from 15–21%) and statistically reduced linolenic acid levels. Neither mutant combination appears to affect other agronomic properties such as plant morphology or seed protein levels making this a potentially viable trait.     

重质碳酸钙活化的研究

采用硬脂酸对1500目重质碳酸钙进行湿法活化,利用正交实验研究了硬脂酸加入量、反应温度和反应时间对活化效果的影响。测定了改性前后重质碳酸钙活化度,并用红外光谱进行表征。     

Synthesis and humidity sensitive properties of nanocrystalline Ba1−xSrxTiO3 thick films

Nanocrystalline Ba_1−xSr_xTiO₃ (x=0, 0.2, 0.4, 0.6, 0.8 and 1.0) precursors were synthesized using the stearic acid gel method. After the precursors had been calcined at 600–950°C for 0.5–1 h, nanocrystalline powders with the cubic perovskite structure were obtained and these were made into thick films. The powder samples were characterized by differential thermal analysis, X-ray diffraction and transmission electron microscopy, and the thick film samples were characterized by scanning electron microscopy and X-ray diffraction. The humidity-sensitive properties of the nanocrystalline Ba_1−xSr_xTiO₃ thick films were investigated. The results show that these nanocrystalline thick films possess higher humidity sensitivity and lower resistance than those of conventional materials.     

Tree-to-tree variation in stearic and oleic acid content in seed fat from Allanblackia floribunda from wild stands: Potential for tree breeding

We determined whether Allanblackia floribunda, a forest tree species that is valued for the fat extracted from its seeds, could be genetically improved for fruit/seed production by sampling 17–40 fruits from each of 70 trees that were distributed among four sites in wild stands. Fat was extracted from the seeds, and stearic and oleic acid content of the fat was estimated. Highly significant (P < 0.0001) between- and within-tree variation characterised fruits and seed characters. Between-site phenotypic variation was not significant. Stearic and oleic acid percentages in seed fat ranged from 44.16% to 66.12%, and from 24.95% to 48.42% per tree sample, respectively. Moderate repeatabilities were identified in fruit characters and mean seed mass. Moderate positive relationships were found between stearic and oleic acid percentages. Seed fat profiles were not found to vary with other fruit characters. Twenty “plus trees” were selected for breeding.     

乙撑双硬脂酰胺的制备

以乙二胺和硬脂酸为原料制备乙撑双硬脂酰胺,考查了原料配比、滴加时间、反应温度对产品收率的影响,确定合成工艺的最佳条件为:硬脂酸与乙二胺的摩尔比2.5∶1,滴加时间1 h,反应温度160℃,最高收率98.12%。产物结构用红外光谱、元素分析等方法进行表征。     

用于机械加工石蜡材料的改性研究

研究了硬脂酸、增韧剂A、聚乙烯以及冷却方式对石蜡体系的性能影响,通过物理改性,制备了适用于机械加工的石蜡复合体系。实际应用表明,该石蜡复合体系能满足数控加工要求,效果良好。     

硬脂酸包覆超微镍粉的合成与性能表征

用硬脂酸对微波吸收剂微纳米金属镍表面进行有机改性,对包覆样品进行了红外漫反射表征、包覆含量测定、分散性、润湿性以及耐酸性等结构与性能研究.结果表明:包覆样品的疏水性和耐酸性明显优于未包覆的镍粉,适量的硬脂酸包覆超微镍粉后可以大大提高镍粉的分散性.     

Synthesis of LiFePO4/carbon composite from nano-FePO4 by a novel stearic acid assisted rheological phase method

LiFePO₄/carbon composite was synthesized at 600 °C for 4 h in an Ar atmosphere by a stearic acid assisted rheological phase method using amorphous nano-FePO₄ as the iron source. XRD, SEM and TEM observations show that the LiFePO₄/carbon composite has good crystallinity, ultrafine and well-dispersed particles of 60–150 nm size and in situ carbon coated on the surface of LiFePO₄ crystallites. The synthesized LiFePO₄/carbon composite shows a high discharge capacity of 160 mAh g⁻¹ and 155 mAh g⁻¹ at rates of 0.5 C and 1 C, respectively. Even at a high current density of 30 C, the material still presents a discharge capacity of 93 mAh g⁻¹ and exhibits an excellent cycling performance.     

Characterization and In-vitro Permeation Study of Stearic Acid Nanoparticles containing Hinokitiol

Lipid nanoparticles containing hinokitiol (HKL) were prepared by a melt–emulsification method. Stearic acid was used as a lipid for the matrix material of the nanoparticles. According to results from transmission electron microscopy (TEM) and dynamic light scattering (DLS), most of the nanoparticles were less than 100 nm. When nanoparticles containing HKL were scanned on a differential scanning calorimeter, no endothermic peak of HKL was observed. This means that HKL in the lipid matrix of the nanoparticles is in a dissolved state. In an 18-h permeation study using hairless mouse skin mounted on a diffusion cell, the amount of HKL encapsulated in the nanoparticles transported to the receptor cell was five to ten times more than for HKL dissolved either ethanol or propylene glycol. Therefore, stearic acid nanoparticles strongly enhanced permeation of the skin by HKL.