星型环氧乳化剂合成及乳液的性能研究

采用自制星型乳化荆合成水性环氧乳液，考察了乳化剂的结构与环氧乳液稳定性及涂膜性能的关系，优化了乳化荆在制备环氧乳液过程中的主要参数。研究结果表明：聚乙二醇和环氧树脂E-20中环氧基与羟基的物质的量比为1．5：1．0、聚乙二醇的相对分子质量为4000、乳化剂用量为10％时，制备的环氧乳液稳定性高、成膜性能优良。     

影响烟草切茎繁殖的几个因素分析

带叶切割５～６茎节烟苗茎节置２８℃沙床保湿培养，６～１０ｄ茎上生出不定根，同时腋芽开始生长。１株烟苗经２次无性繁殖可扩增到２５～３５株。该无性系在株高、单株叶数、抗病性等方面均比亲本实生苗整齐     

马来海松酸型聚氨酯烘漆耐热性研究

以马来海松酸酯多元醇为原料，制备了马来海松酸型聚氨酯烘漆，利用热重法，讨论了不同原料组分及配比，固化温度和固化时间等因素对烘漆耐热性的影响，另外，还利用ＤＳＣ，对二月桂酸二丁基锡对封闭异氰酸酯组分热解封温度的影响了讨论。     

Preparation of Pectin/Chitosan Synbiotic Microcapsules and Its Study on Simulated Gastrointestinal Environments and Storage Stability

Pediococcus acidilactici and inulin were used as wall cores,with pectin and chitosan as the shell material.The conditions of microencapsulation were optimized by analyzing the embedding rate,particle morphology,the mechanical strength,gastrointestinal tolerance in vitro and storage performance.The experimental group was divided into three groups:Free Pediococcus acidilactici group (PA),microcapsule group made by embedding Pediococcus acidilactici alone (PC(PA)MCs),synbiotic microcapsule group made by embedding inulin and Pediococcus acidilactici (PC(PA-I)MCs).The results showed that the appearance,particle size,mechanical strength and embedding rate of microcapsules were better when the mass concentration of pectin was 5 g/100 mL,the content of inulin was 25 mg/mL and the mass concentration of chitosan was 0.8 g/100 mL.Through the gastrointestinal tolerance test in vitro, it was found that PC(PA-I)MCs group was relatively stable in the artificial gastric juice in vitro (P<0.05).At the same time,it began to release rapidly in the artificial intestinal fluid in vitro at 30 min and it was almost completely disintegrated after 2 h.It was found that the cell survival rate of PA group decreased significantly at cold and room temperature through the storage test for 4 weeks.While the cell survival rate of PC(PA-I)MCs group decreased slightly.And the cell survival rate of PC(PA-I)MCs group was higher than that of PC(PA)MCs group (P>0.05).At room temperature,the cell survival rate of PC(PA-I)MCs group was higher than that of PC(PA)MCs group (P>0.05).In summary,pectin/chitosan microcapsules with inulin as probiotics had a better embedding effect on Pediococcus acidilactici.     

弹性地基上圆柱壳的稳定性

对弹性地基上轴压和侧压圆柱壳的稳定性进行了分析，提出了壳体在弹性地基上的临界载荷的新算法。     

玫瑰花红色素及其稳定性研究

对玫瑰花色素作为新型天然食用色素的可行性进行了初步研究。通过纸色谱法、紫外分光光度法、酸碱反应、氯化亚铁显色反应、盐酸镁粉反应、中性醋酸铅沉淀反应等。初步鉴定了化学成份。对光、温度、ＰＨ值、氧化介质、还原价质、蔗糖、食盐、铝制品、铁制品、铜制品、锡制品等对比色素的影响，进行了初步探讨，结果表明，其主要成份为黄酮类化合物；对光、热耐受性好；适用ＰＨ值范围宽；耐氧化性较差，耐还原性较好；Ｆｅ＾３＋和Ｓ     

Depletion of ascorbic acid derivatives in fish feed by the production process

ABSTRACT:   The depletion of ascorbic acid derivatives in fish feed during the feed processing (extrusion cooking and drying) was studied at five extrusion cooking temperatures and at 85°C for 2 h dryer processing temperature. Three ascorbic acid derivatives were used: L-ascorbyl-2-mono-phosphate Mg (APM), L-ascorbic acid sodium (AAS) and L-ascorbic acid palmitic acid ester (AAP). Samples were collected after drying and ascorbic acid derivatives losses evaluated. APM was found to be quiet stable with an average retention of 88%, but AAS and AAP were unstable and the depletion was very high.     

微囊化沙门菌SP4噬菌体的制备及其缓释特性分析

通过采用阳离子醚化淀粉/海藻酸钠/黄原胶/纳米TiO₂/壳寡糖为原料制备微囊化SP4噬菌体,为控制沙门菌感染提供生物制剂。选用沙门菌SP4噬菌体,采用液滴法来制备微囊化SP4噬菌体,并对其效价、阳离子醚化淀粉浓度、海藻酸钠浓度、黄原胶浓度、壳寡糖浓度、pH稳定性、热稳定性、模拟胃液稳定性、模拟肠液释放行为以及保存稳定性进行分析。结果显示,当阳离子醚化淀粉浓度为2.4%、海藻酸钠浓度为2%、黄原胶浓度为1%、壳寡糖浓度为0.6%时,微囊化SP4噬菌体微球外形规则,包封率为97.5%,在pH5.0~8.0、温度10~30℃、模拟胃液pH2.0、0~30 min和pH3.0、0~150 min噬菌体保持较高的生物学活性,模拟肠液中4 h,噬菌体完全释放,4℃环境下保存6周噬菌体效价无明显降低。综上表明,微囊化沙门菌SP4噬菌体显著提高了噬菌体的稳定性和缓释性能,其耐酸特性利于抵御胃酸的分解,具有应用于生物防治的潜力,为进一步采用多因素试验制备微囊化沙门菌SP4噬菌体奠定了基础。     

抗菌肽CRAMP的安全性、稳定性及其在清除铜绿假单胞菌生物被膜中的作用

旨在考察鼠源抗菌肽CRAMP的安全性、稳定性及其在清除铜绿假单胞菌生物被膜中的作用。采用兔血红细胞悬液的溶血性和小鼠腹腔巨噬细胞(RAW264.7)的细胞毒性考察CRAMP的安全性;采用不同温度、蛋白酶、金属离子和酸碱梯度对CRAMP抗菌活性的影响,考察其稳定性;通过在6孔细胞培养板中构建铜绿假单胞菌(PAO1株)成熟生物被膜,以人源抗菌肽LL-37和3种抗菌药为对照,采用结晶紫染色法检测生物被膜量,平板菌落计数法对生物被膜活菌数进行计数,苯酚-硫酸法结合Folin-酚试剂法检测生物被膜胞外基质含量,激光扫描共聚焦显微镜(CLSM)观察CRAMP干预PAO1生物被膜形态学的变化。结果显示,CRAMP在所测试浓度下对兔血红细胞溶血率均<2%;在62.5~125 mg·L^-1时对 RAW264.7没有细胞毒性。温度(25~100 ℃)、两种盐离子(Na⁺、K⁺)以及pH为5~10时对CRAMP的抗菌活性没有影响;胃蛋白酶、木瓜蛋白酶、胰蛋白酶均不同程度影响了CRAMP的抗菌活性。6孔细胞培养板中,4倍MIC 的CRAMP极显著降低了PAO1生物被膜量(减少率为76.74%,P<0.01),极显著减少了生物被膜中的活菌数量(减少了1.2个CFU·mL^-1,P<0.01),效果优于LL-37和3种抗菌药。CRAMP组的胞外基质显著低于空白对照组和LL-37组(P<0.05)。CLSM结果显示：与对照组相比较,4MIC浓度下,CRAMP组的细菌总荧光强度(PI+SYTO)显著低于空白对照组和LL-37组(P<0.05);与空白对照组相比,CRAMP组和LL-37组的死菌荧光强度/活菌荧光强度比值 (PI/SYTO)均极显著增大(P<0.01)。综上表明,CRAMP具有低溶血性、低细胞毒性,除蛋白酶作用不稳定外,具有较好的稳定性,对PAO1成熟生物被膜具有明显的清除作用,且效果优于LL-37,具有良好的药物开发前景。     

葡萄糖氧化酶纳米粒的制备及其体内外抗菌效果

为了使葡萄糖氧化酶更加稳定,利用可逆加成-断裂链转移自由基聚合反应对葡萄糖氧化酶进行纳米包裹。动态激光散射仪测定显示,包裹后粒径为(12.4±1.0)nm, Zeta电位为(+4.2±0.5)mV。通过冻融循环、长期储存和胰蛋白酶试验证明了包裹后的稳定性。在体外,对大肠杆菌的最低抗菌浓度为0.01 mg/mL。对新西兰大白兔细菌肿包治疗显示,包裹后的葡萄糖氧化酶较包裹前有较好的稳定性和抑菌效果,可作为新型抗菌制剂。