超声波用于羟乙基纤维素的合成研究

将超声波技术用于羟乙基纤维素的合成研究。实验结果表明 ,在羟乙基纤维素的合成过程中使用超声波 ,反应时间比液相法缩短了一半 ,醚化率提高 2 0 %。所得产品完全符合美国试验与材料协会的HEC分析方法 ,即ASTMD2 364- 89所规定的各项指标要求。超声波用于羟乙基纤维素合成的最适宜工艺条件为 :超声波辐射时间在 40～ 5 0min ,辐射强度 30kHz,原料配比∶m(Cell)∶m(EO) =1∶1 .2 ,醚化温度 5 0± 5℃。     

高浓度酒精补料发酵工艺的研究

用酵母Y0 0 2发酵玉米糖化后过滤清液 ,在 34℃条件下 2 4h内二次补糖 ,控制总糖浓度在 2 5± 1 % ,发酵 65h左右酒精浓度可达 1 5 % (v/v,2 0℃ )以上 ,残糖降至 0 .3 %以下 ,糖利用率达 92 %左右     

乳状分散聚乙烯蜡的研制

对乳状分散聚乙烯蜡制备的乳化温度、搅拌速度、初期转相水量和助剂等进行了研究。实验结果表明 ,乳化温度为 1 0 5℃± 5℃、搅拌速度为 60 0～ 30 0 0r/min、初期转相水质量分数为2 5 %时 ,能得到具有良好性能的乳状分散聚乙烯蜡产品     

乳清蛋白凝胶条件的研究

以乳清蛋白为研究对象，研究了乳清蛋白浓度、温度、加热时间、pH值、金属离子等因素对乳清蛋白凝胶形成的作用。结果显示，乳清蛋白形成凝胶的基本条件是乳清水溶液浓度大于0．133g／mL，温度高于85℃±2℃，当温度在85℃±2℃～90℃±2℃之间，凝胶形成时间随乳清蛋白浓度变大而减少，在沸水中乳清蛋白浓度对凝胶形成时间影响不大，在19min左右；酸性条件下乳清蛋白形成凝胶的最适pH为5．3，pH小于1．2在沸水中加热30min，乳清蛋白形成碎块状凝胶，碱性条件下形成凝胶的最适pH为8．3，pH大于12．8在沸水中加热30min，乳清蛋白变为红色；钙离子的添加可使乳清蛋白形成凝胶所需时间减少到6min。     

酶法改性樟树籽仁油制备含ω-3多不饱和脂肪酸 结构脂质及其理化性质与抗氧化活性

采用固定化脂肪酶Novozyme 435催化鱼油乙酯和樟树籽仁油（CCSKO）酯交换制备含ω-3多不饱和脂肪酸结构脂质。通过单因素试验对制备工艺条件进行优化,得到的最佳反应条件为：底物摩尔比1∶ 1,反应温度60 ℃,反应时间8 h,酶载量10%（以底物质量计）。在最佳反应条件下,含EPA/DHA结构脂质的含量为(24.34±0.33)%,且酶重复稳定性较好。放大制备试验后,采用150 ℃短程分子蒸馏纯化,产物中结构脂质含量达到（44.22±0.57）%,中碳链脂肪酸、长碳链脂肪酸含量比例约为3∶ 1, EPA含量为（11.91±0.44）%,DHA含量为（7.67±1.11）%。结构脂质的甘油三酯组成主要为CC-EPA（(11.07±0.11）%)、CC-DHA（(6.71±0.21)%）、CLa-EPA（(7.78±051)%）和CLa-DHA（(5.99±0.25)%）。制备的结构脂质的酸价（KOH）为（0.39±0.08）mg/g,皂化值（KOH）为（250.31±1.02）mg/g,碘值（I）为（54.87±0.86）g/100 g,过氧化值为（1.12±001）mmol/kg,均符合食用油脂制品国家标准。结构脂质清除DPPH自由基及ABTS自由基的IC50值分别为（13.92±0.18）mg/mL及（8.99±0.05）mg/mL,表明其具有较强的抗氧化能力。     

携式pH仪

Kane-May公司研究开发小组制成了一种称为KM7002型高规格数字式温度pH值测量仪。该仪器能自动进行温度补偿。 为了得到精确的pH值读数,温度测量就必须精确。KM7002型测量仪的pH值测量误差为±0.02,分辨力为0.01pH。该仪器能从-30℃至+450℃范围内测量温度,其读数误差为±0.7％,分辨力为1℃。能用 Kane-May 40系列的任何一只温度测量探头进行操作。     

大黄鱼鱼油的制备及其理化性质

以新鲜大黄鱼为原料,通过石油醚（沸程30~60 ℃）提取大黄鱼鱼油,并对大黄鱼鱼油的酸值、过氧化值、茴香胺值、共轭二烯值、脂肪酸组成、生育酚、胆固醇、角鲨烯、挥发性成分及磷脂组成进行测定。结果表明：大黄鱼鱼油得率为（31.25±3.66）%;大黄鱼鱼油酸值（KOH）为(0.59±005)mg/g,过氧化值为（5.50±0.76）mmol/kg,茴香胺值为0.30±0.06,共轭二烯值为22.32±109;大黄鱼鱼油中共检出17种脂肪酸,不饱和脂肪酸含量高达67.27%,其中油酸占（31.03±010）%、亚油酸占（12.21±0.07）%、DHA占（7.21±0.12）%、EPA占（4.48±0.03）%;大黄鱼鱼油中检出4种生育酚,主要是α-生育酚,含量为4.18 mg/100 g,β、γ、δ-生育酚含量均小于0.12 mg/100 g;大黄鱼鱼油中角鲨烯含量为40 mg/100 g,胆固醇含量为380 mg/100 g;大黄鱼鱼油中共鉴定出31种挥发性成分,主要包括醛、酮、醇、烷烃类;大黄鱼鱼油中磷脂含量较高的组分为PG（30∶ 0/16∶ 0）（19.61 mg/g）和PG（28∶ 0/16∶ 1）（10.87 mg/g）。     

可溶性固定化胰蛋白酶的制备及性质研究

将胰蛋白酶偶联在亲水性高分子聚合物N-琥珀酰壳聚糖上,制备得到水溶性固定化胰蛋白酶,并对其部分酶学性质进行了研究。结果表明,可溶性固定化胰蛋白酶的最适pH为9·0,最适温度为60℃,Km值为0·28mg/mL;该酶在pH6·0以上能够完全溶解,在pH4·0左右基本不能溶解;可溶性固定化胰蛋白酶在60℃条件下,保温8h,仍有55%的活性;在4℃条件下,30d后活性保留达98%;在4℃下保存72h,活性没有明显降低。pH8·0~10·0稳定性最好(相对活性>90%)。     

涤纶针织布的有机硅改性聚酯-聚醚共聚物整理

采用酯交换-缩聚反应,在催化剂与稳定剂的作用下,以对苯二甲酸二甲酯、乙二醇、聚乙二醇与自制聚醚硅油为原料合成了有机硅聚酯-聚醚共聚物整理剂。试验探究了聚醚硅油的用量对反应产物性能的影响,通过红外光谱表征了有机硅聚酯-聚醚共聚物的结构,并对其在涤纶针织物上的最佳应用条件进行了研究。结果表明:聚醚硅油用量占酯交换反应物质量分数为6%时,用其处理的针织物亲水性和手感较好;最佳使用工艺条件为浸轧法,质量浓度20 g/L,120℃焙烘60s。     

温度对红秋葵采后生理和品质的影响

测定了红秋葵嫩果采收后在不同的贮藏温度(30±2℃、15±1℃、9±1℃、4±1℃)下外观、果重、呼吸强度、VC含量等品质和生理指标的变化。结果表明,红秋葵在14～16℃贮藏,各种指标变化最小,果实外观较好。四种温度中,15±1℃为红秋葵最佳贮藏温度。     

丙二醇酯中游离丙二醇含量的直接测定

提出丙二醇酯中游离丙二醇含量的直接测定方法。该法和萃取法对一系列样品进行对照试验,经数理统计分析,结果表明,两种测定方法没有显著性差异。直接法更简单、快捷。回收率为95.7?.0%,相对标准偏差为0.23%0.60%。     

乙二醇葡萄糖苷的制备与分离提纯

以葡萄糖和乙二醇为原料,以磷酸为催化剂,制备了乙二醇葡糖苷,研究了原料比、反应温度、反应时间、催化剂用量对葡萄糖转化率的影响,并用正丁醇萃取的方法从乙二醇葡糖苷中除去乙二醇。     

提高水基聚氨酯树脂凃膜耐水性的研究

对丙酮法合成的水基聚氨酯树脂凃膜耐水性的提高进行了报导。作者选用了硬脂酸单甘脂(GMS)、聚硅氧烷二醇作为小分子扩链剂并以二聚酸聚酯二醇作为软段合成了含有侧链的水基聚氨酯树脂系列、探讨了DMPA用量、聚氨酯侧链结构种类等因素对水基聚氨酯树脂分散体涂膜耐水性的影响。合成出了耐水性更好的水基聚氨酯树脂皮革涂饰剂。     

芦苇乙二醇制浆的研究

在常压下,利用低浓度的乙二醇溶液蒸煮芦苇,分别做了酸用量、液固比和有机溶剂浓度实验.研究结果表明:乙二醇在常压下表现出良好的纤维素、木质素分离趋势,在乙二醇40%、催化剂10%、水50%、酸3%和液固比20:1时,纤维素、木质素分离效果最佳,浆的质量较好;乙二醇通过蒸馏回收可以循环利用,并可得到较纯的木质素.     

壳聚糖/聚乙二醇共混膜性能研究

制备了不同配比的壳聚糖/聚乙二醇共混膜,利用差示扫描量热仪和动态热机械分析仪对共混膜的热性能进行了测试,结果表明:随着聚乙二醇含量的增多,共混膜的玻璃化转变峰越宽,膜的韧性提高,玻璃化转变温度、结晶度和刚度降低.     

壳聚糖/聚乙二醇共混膜的制备与表征

将壳聚糖和聚乙二醇熔融共混,制备了纯壳聚糖膜和不同质量比的共混膜.利用傅立叶红外光谱仪、原子力显微镜、扫描电子显微镜对各种共混膜的结构、形貌进行表征.结果表明,聚乙二醇与壳聚糖间存在强的氢键作用,并且随着聚乙二醇的加入,共混膜表面出现大小不一的孔洞结构,从而证明两组分在熔融共混过程中存在超分子相互作用,并讨论了这种作用的可能机理.     

Effects of propylene glycol or fat drench on plasma metabolites,liver composition,and production of dairy cows during the periparturient period

Forty-eight Holstein cows were used to determine the effects of short-term oral drenches of propylene glycol (PG) and Ca-soaps of palm oil fatty acids (fat) on plasma concentrations of key metabolites, liver composition, and milk production during the first 3 wk of lactation. Treatments (2 x 2 factorial arrangement) given orally once daily for the first 3 d postpartum were water (control), 500 ml of PG, 454 g of fat, or 500 ml of PG plus 454 g of fat. All treatments were administered as a total volume of 1.9 L. Administration of PG decreased concentrations of nonesterified fatty acids (NEFA) in plasma during the first 7 d and the first 21 d postpartum and tended to decrease concentrations of beta-hydroxybutyrate during the first 7 d postpartum. Concentrations of insulin in plasma were not affected by treatment. Administration of either PG or fat increased plasma glucose and liver glycogen concentrations compared to the control or PG plus fat treatments. Concentrations of triglycerides in liver were not affected by treatment. Administration of PG did not affect dry matter intake or milk yield and composition during the first 3 wk postpartum; however, cows drenched with fat tended to have lower dry matter intake and milk yield during the first 3 wk of lactation. Short-term drenching of PG effectively decreased NEFA concentrations in plasma during early lactation; however, data do not support administration of fat via drench to early lactation cows and concurrent administration of dietary fat appears to blunt the metabolic response of cows to PG.     

大豆磷脂酰乙醇胺-聚乙二醇单甲醚2000的制备及其性能研究

以聚乙二醇单甲醚2000为原料,先将其氧化为聚乙二醇单甲醚2000羧基衍生物,再制备成高活性的聚乙二醇单甲醚2000酰氯,与磷脂反应制备了大豆磷脂酰乙醇胺-聚乙二醇单甲醚2000(MPEG2000-SPE)。产物结构经1HNMR和IR进行了表征。质量比为m(大豆粉末磷脂)∶m(羧基化聚乙二醇单甲醚)=3∶1,产物收率为85.2%;通过TEM观察了产物在水中形成胶束的大小,通过荧光探针技术研究了产物的临界胶束浓度用以表征产物的热力学稳定性,通过乳化力来表征产物的动力学稳定性,试验表明,产物在水溶液中形成的胶束粒径为30~80 nm,临界胶束浓度为2×10-6mol/L,形成胶束的热力学稳定性优于小分子胶束,产物的动力学稳定性优于大豆粉末磷脂。     

Randomized clinical field trial on the effects of butaphosphan-cyanocobalamin and propylene glycol on ketosis resolution and milk production

The purpose of this study was to determine the effects of a butaphosphan-cyanocobalamin combination product (B+C) and 2 durations of propylene glycol treatment (PG; 3 versus 5 d) on ketosis resolution and early lactation milk yield. Cows from 9 freestall herds (8 in Ontario and 1 in Michigan) were tested at weekly intervals between 3 and 16 d in milk. Ketosis was defined as blood β-hydroxybutyrate (BHB) ≥1.2 mmol/L. Ketotic cows were randomly assigned to treatment with 25 mL of B+C or 25 mL of saline placebo for 3 d and 3 or 5 d of 300 g of PG orally in a 2 × 2 factorial arrangement. Outcomes evaluated for all farms included ketosis cure (blood BHB <1.2 mmol/L at 1 wk after enrollment), maintenance of ketosis cure (blood BHB <1.2 mmol/L 1 and 2 wk after enrollment), and blood BHB concentrations at 1 and 2 wk after enrollment. Daily milk weights were collected in 3 herds. Poisson regression was used to evaluate cure and maintenance of cure, whereas repeated-measures ANOVA was used to evaluate blood BHB concentrations in the 2 wk after enrollment and average daily milk production in the 30 d after treatment. A total of 594 animals were enrolled in the study with 124 treated with B+C and 5 d of PG, 176 treated with B+C and 3 d of PG, 128 treated with saline and 5 d of PG, and 166 treated with saline and 3 d of PG. Animals with blood BHB >2.4 mmol/L at the time of enrollment were 1.7 times more likely [95% confidence interval (CI): 1.4 to 2.2] to cure and had a decrease of 0.25 ± 0.11 mmol/L blood BHB at 1 wk after enrollment if treated with 5 d of PG compared with 3 d, though this response was not seen in animals with BHB of 1.2 to 2.4 mmol/L at enrollment. Cows with blood glucose concentrations <2.2 mmol/L at enrollment produced 3.1 kg/d (95% CI: 1.3 to 5.0) more milk if treated with B+C and 3.4 kg/d (95% CI: 1.7 to 5.1) more milk if treated with 5 d of PG compared with their respective controls. This response was not seen in animals with blood glucose ≥2.2 mmol/L at enrollment and there was no interaction between treatments. These results indicate that extended PG treatment is beneficial in decreasing blood BHB concentrations in more severely affected animals. Additionally, both B+C treatment and extended PG treatment improved milk yield in animals with low blood glucose at the time of ketosis diagnosis.     

用油酸和乙二醇酯化合成加脂剂的研究

以油酸和乙二醇及马来酸酐为主要原料,合成了一种性能优良的加脂剂,同时详细讨论了各步反应的影响因素,得到最佳反应条件,并对该加脂剂进行了应用试验。