树脂型甲醛捕捉剂的研制

在常规脲醛树脂制备工艺基础上,成功制备了树脂型甲醛捕捉剂。借助13C-NMR和GPC分析方法,研究了甲醛捕捉剂的结构特点及分子质量分布。将其与自制的低物质量比脲醛树脂混合使用,考查了甲醛捕捉剂对脲醛树脂性能的影响。结果表明,该甲醛捕捉剂不含游离甲醛,已实现一定程度的树脂化。甲醛捕捉剂中大量游离尿素及一羟甲基脲等低分子质量物质的存在能有效降低刨花板的甲醛释放量,但对混合树脂的最终强度不利。添加甲醛捕捉剂对脲醛树脂的固化行为影响较小。当脲醛树脂与甲醛捕捉剂质量比为85/15、热压时间为4min时,刨花板性能较佳。     

缓释型泥浆清除剂在W9P1井的应用

W9P1井在正常生产过程中被临近井钻进过程中泥浆侵入储层不出液,室内溶蚀实验证明泥浆固结物堵塞伤害无法采取常规酸化措施解除。优选滤饼清除率达82.67%的泥浆清除剂对固结物进行处理,在地层温度下浸泡0.5h后泥浆固结物均匀分散呈粉末状。室内腐蚀实验说明泥浆处理剂可以在管柱表面形成钝化膜,现场施工不用加入任何缓蚀剂,最终确定采用直接注入缓释型泥浆清除剂后抽汲排液的方式进行泥浆解堵。现场施工取得成功,该井恢复产能。     

共轭亚油酸酯类的氧化稳定性研究

本文研究了共轭亚油酸乙酯和共轭亚油酸三甘酯的氧化稳定性,并与富含不饱和脂肪酸的红花籽油比较,探讨了变价金属离子和抗氧化剂对共轭亚油酸乙酯和共轭亚油酸三甘酯的氧化稳定性的影响。结果表明共轭亚油酸三甘酯的氧化稳定性优于共轭亚油酸乙酯的氧化稳定性;加入0.02%VE可明显提高它们的氧化稳定性,而0.02%三氯化铁则减弱了它们的氧化稳定性;VC在共轭亚油酸酯类的油状体系中对抗氧化剂维生素E没有增效作用。     

不同品种杭白菊中酚类物质含量和清除自由基活性的比较

4种酮乡产杭白菊及黄菊和野菊,分别用乙醇-水体系进行热回流提取,用比色法测定醇提物中总酚和总黄酮含量,并用化学发光法检测春清除活性氧自由基的能力。结果表明,不同品种间含量存在较大差异,总酚和总黄酮含量（以菊花干基计）最高提异种大白菊,分别为9.76%和4.46%;最低的是黄山种野菊,分别为3.21%和1.99%。不同菊花均显示了良好的清除活性氧自由基的活性,清.OH和O2^.-的IC50分别在0.54-1.98mg/ml和24.2-54.5ug/ml之间,其中清O2^.-活性最强是大洋菊,最弱是软梗小洋菊;而清.OH能力最强为早小洋菊,最终为异种大白菊,结果表明,菊花中酚类物质的含量高低与抗自由基活性强弱无明显的对应关系。     

电离辐射及超氧阴离子基对人血淋巴细胞姐妹染色单体交换的诱发作用

用姐妹染色单体交换(SCE)作为指标,研究了~(60)Coγ射线辐照及NADH-PMS(吩嗪硫酸甲酯)系统中产生的超氧阴离子自由基(0_2~(·-))对胎儿脐血淋巴细胞染色体的损伤作用,及活性氧清除剂SOD和甘露醇的保护作用。结果显示γ射线及0_2~(·-)都能诱发细胞SCE频率显著升高,且存在一定的剂量-效应关系。SOD及甘露醇对0_2~(·-)诱发的损伤有明显的保护作用。     

甲醛捕捉剂YZ-1在脲醛-三聚氰胺甲醛复合树脂衬布硬挺整理剂中的应用

脲醛-三聚氰胺甲醛复合树脂胶作衬布硬挺整理剂使用时,必然带来甲醛的污染。在基本不影响衬布硬挺整理剂使用效果的情况下,用YZ-1作该复合树脂胶的游离甲醛捕捉剂,具有明显的消醛效果。当初始游离甲醛含量小于1．00％时,YZ-1的施加量小于1．0％,可使游离甲醛含量降至0．10％以下;当初始游离甲醛含量在2．00％～6．00％时,YZ-1的施加量为4．0％,可使游离甲醛含量降至0．22％。     

Ultraviolet Irradiation Effect on Polyvinylpyrrolidone/Polyaniline Films with Additives

Polyvinylpyrrolidone/polyaniline (PVP/PANI) with additives (TiO₂, ZnO, NaCl and Na₂SO₄) was synthesized. To spread the electric and photoelectric applications of PVP/PANI, its photodegradation under UV irradiation was studied by Fourier transform infrared spectroscopy, diffuse reflectance spectroscopy, water uptake and scanning electron microscopy. Results show that ZnO, TiO₂ and NaCl accelerate the photodegradation, respectively, but Na₂SO₄ stabilized PVP/PANI. The degradation rate of PVP/PANI/tert-butyl alcohol and PVP/PANI/ascorbic acid proved the radical role. Water uptake results show that the power of interactions is in this order: PVP/PANI/Na₂SO₄?>?PVP/PANI/TiO₂?>?PVP/PANI/ZnO?>?PVP/PANI?>?PVP/PANI/NaCl?>?PVP/PANI/tert-butyl alcohol>PVP/PANI/ascorbic acid.     

Effect of processing of corn for production of masa,tortillas and tortilla chips on the scavenging capacity of reactive nitrogen species

The effect of processing conventional and pigmented corn into masa, tortilla and tortilla chips on the ability to scavenge nitric oxide (NO) and peroxynitrite (ONOO^?) was investigated. The level of retention of nitric oxide and peroxynitrite (mediated for inhibition of nitrite formation scavenging capacity for masa, tortilla and tortilla chips) ranged 56.2–78.2%, 67.4–45%, 40.3–62.0% (for nitric oxide) and 38.6–81.7%, 23.3–47.7%, 19.3–67.2% (for inhibition of nitrite formation), respectively. The antinitrosative activities were affected significantly (P > 0.05) by nixtamalisation, but not by processing masa into tortilla and tortilla chips (P > 0.05). The yellow variety and its corresponding products showed the greatest capacity to scavenge nitric oxide and inhibition of nitrite formation among conventional varieties and the purple variety ranked highest among the pigmented varieties.     

Improving antioxidant activity and nutritional components of Philippine salt-fermented shrimp paste through prolonged fermentation

The antioxidant activity and nutritional components of Philippine salt-fermented shrimp paste were improved through prolonged fermentation (90, 180, and 360 days). The antioxidant ability against 1,1-diphenyl-2-picryhydrazyl (DPPH) radical, hydrogen peroxide, and lipid peroxidation increased significantly with prolonged fermentation and were suggested to be related with the Maillard reaction products formed, as measured by the characteristic browning and fluorescent developments. Polyunsaturated fatty acids like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the shrimp paste were not substantially damaged for 360 days, while free amino acid content dramatically increased at 90 days. However, excessive fermentation showed slight but significant decrease in free amino acids and increase in ammonia. These results suggest that properly prolonged fermentation would improve antioxidant ability and some nutritional value in the salt-fermented shrimp paste.