中空聚合物微球的制备Ⅲ.种子扩径的影响

以预乳化液连续滴加进料的三段乳液聚合结合碱酸溶胀处理制备了单分散性良好、大粒径的聚(甲基丙烯酸-甲基丙烯酸甲酯-丙烯酸丁酯)/聚(甲基丙烯酸-苯乙烯)中空聚合物微球。实验发现,在二段乳液聚合种子扩径中,种子乳胶粒数目、乳化剂用量、预乳化液滴加时间等对避免新乳胶粒的生成、扩大种子乳胶粒的粒径有影响,并找到了各自的较优值;扩径单体中的丙烯酸丁酯含量显著影响扩径乳胶粒聚合物的玻璃化温度,进而决定碱酸处理温度。     

超滤膜在果汁加工中的应用研究

选用中空纤维PAN膜、羧基化改性的PAN板式膜、PS膜和PS-SPS膜四种国产膜材料对苹果汁进行超滤澄清处理,比较不同膜对苹果汁理化指标的影响以及处理果汁的最佳条件、最佳工艺。     

Tocopherol oil concentration in field-grown sunflower is accounted for by oil weight per seed

Tocopherols are natural antioxidants that increase the stability of fat-containing foods and perform important biological activities. Significant variations (389 to 1873 μg g oil⁻¹) in the total tocopherol concentration of sunflower seed oil have been reported. The main objectives of this work were to determine the influence of intercepted photosynthetically active radiation on tocopherol concentration during seed filling and to establish and validate relationships between tocopherol concentration in oil and other quality variables of the seed. Seven sunflower hybrids were grown under good water and nutritional conditions in two similar experiments carried out in two contrasting environments. Treatments were applied to modify the amount of radiation intercepted per plant during seed filling in order to obtain a range in oil yield per plant and its components. Greater per plant intercepted radiation decreased the tocopherol concentration in oil. Tocopherol concentration decreased when oil weight per seed increased. Tocopherol concentration stabilized for oil weight per seed higher than 23 mg oil seed⁻¹. This exponential relationship accounted for 73% of the variability in tocopherol concentration (507 to 1203 μg g oil⁻¹) despite differences in hull type, locations, hybrids, and radiation treatments. The proposed relationship acceptably predicted independent results. Crop management techniques could lead to seeds with greater concentrations of tocopherols.     

纳米薄层SAPO-5分子筛的离子热合成及催化性能

以小剂量的丁二酸、氯化胆碱和四乙基溴化铵复配形成的低共熔混合物为溶剂和模板,以水热法合成的纳米薄层SAPO-5分子筛作为晶种,使用离子热法在微波加热功率为400 W、温度为180℃和晶化时间为20 min的条件下,高效合成了具有六角花瓣状的纳米薄层SAPO-5分子筛。采用XRD、SEM、N2物理吸/脱附和NH3-TPD对合成样品的物相、形貌、孔结构和酸性进行了分析。结果表明,所合成的样品SC2-T180-t20-P400是一种同时含有微孔-介孔-大孔结构的多级孔SAPO-5分子筛,其外表面积高达85m2/g。分子筛产物中无机物的原子利用率达到88%。该样品在苯与苯甲醇的烷基化反应中,苯甲醇转化率和二苯甲烷选择性分别达到99.9%和94.0%,表现出比传统水热法合成的纳米薄层SAPO-5催化剂更为优异的催化性能。     

Sex pheromone of the mullein bug,Campylomma verbasci (Meyer) (Heteroptera: Miridae)

The first known sex pheromone for the family Miridae is reported for the mullein bug,Campylomma verbasci (Meyer) (Heteroptera: Miridae). Extracts of and Porapak Q-trapped volatiles from females were attractive to males in field bioassays. Butyl butyrate and hexyl butyrate were the predominant compounds in the females' volatiles, but these compounds previously had been found to be inactive when released alone or in combination. Butyl butyrate in combination with an isolated trace chemical, (E)-crotyl butyrate (which was inactive alone), rivaled the attraction elicited by five live females. When synthetic butyl butyrate and (E)-crotyl butyrate in a 16: 1 ratio were released at 91 or 183 g/day, they comprised an effective attractant for male bugs.     

微粒群优化和区域生长结合的彩色图像分割算法

提出了一种微粒群优化和区域生长相结合的彩色图像分割算法,以彩色图像直方图中自适应搜索到的峰值作为像素种子。由于搜索像素种子点是按密度进行,计算量小,大幅度提高了算法的计算速度,同时克服了传统区域生长方法不能自动选择种子且容易导致过分割的局限性。实验表明：该方法提高了图像分割速度,并可以准确地分割出目标,是一种有效的图像分割方法。     

新型就仓干燥技术处理高水分玉米种子的实仓应用效果分析

应用低温缓速均匀通风基本原理设计的设备系统,对堆高2 m的58 t散装高水分玉米种子(籽粒,入仓平均水分20.2%)进行就仓干燥处理.经过累计301.5 h的间断式处理,按预定降水目标12.5%,结果以40多个固定和临时取样点的跟踪检测,实际降低到平均12.4%(最高12.9%,最低11.7%);对水分检测结果的离散性分析表明,在无霉变、无损伤、无抛洒、不影响种子活性的前提下,能够达到精确控制调节粮食水分的要求.     

麻疯树籽粕中毒蛋白的提取

研究了溶剂浸提法提取麻疯树籽饼粕中麻疯树毒蛋白时的各影响因素,考察了提取时间、提取温度、pH值、缓冲液浓度和无机盐浓度对麻疯树毒蛋白溶出的影响.结果表明:提取液pH值是影响麻疯树毒蛋白溶出的最重要因素,提取时间、缓冲液浓度及盐浓度对提取也有一定影响.通过正交试验获得最佳提取条件:提取时间3 h,提取温度25℃,提取液为浓度0.4 mol/L的NaCl溶液,pH=7.在此条件下得到的毒蛋白占去壳种仁的质量分数的0.39%.     

Biodiesel development from high acid value polanga seed oil and performance evaluation in a CI engine

Non-edible filtered high viscous (72 cSt at 40 °C) and high acid value (44 mg KOH/gm) polanga (Calophyllum inophyllum L.) oil based mono esters (biodiesel) produced by triple stage transesterification process and blended with high speed diesel (HSD) were tested for their use as a substitute fuel of diesel in a single cylinder diesel engine. HSD and polanga oil methyl ester (POME) fuel blends (20%, 40%, 60%, 80%, and 100%) were used for conducting the short-term engine performance tests at varying loads (0%, 20%, 40%, 60%, 80%, and 100%). Tests were carried out over entire range of engine operation at varying conditions of speed and load. The brake specific fuel consumption (BSFC) and brake thermal efficiency (BTE) were calculated from the recorded data. The engine performance parameters such as fuel consumption, thermal efficiency, exhaust gas temperature and exhaust emissions (CO, CO₂, HC, NO_x, and O₂) were recorded. The optimum engine operating condition based on lower brake specific fuel consumption and higher brake thermal efficiency was observed at 100% load for neat biodiesel. From emission point of view the neat POME was found to be the best fuel as it showed lesser exhaust emission as compared to HSD.     

Chinese melon (Momordica charantia L.) seed: Composition and potential use

Chinese melon (Momordica charantia L.), also known as bitter gourd, is a tropical crop, grown throughout Asian countries for use as food and medicinals. In 1993, four cultivars of Chinese melon were grown in Mississippi and the seeds were collected. Oil contents of the seeds ranged from 41 to 45% and the oils contained 63–68% eleostearic acid and 22–27% stearic acid. Industrially important tung oil, a “fast-drying oil” used in paints and varnishes, contains 90% eleostearic and 2–3% stearic acid. The ratio of stearic to eleostearic in Chinese melon seed oil is ten times greater than that in tung oil. The higher ratio should reduce the rate of drying and crosslinking and could be advantageous in the paint industry. The defatted meals contained 52–61% protein and would be a good source of methionine.