生物法在造纸废水处理中的应用

造纸废水中含有大量有机物,且含有木质素、纤维素等难降解物质,色度高,SS高,水质成份复杂.对造纸废水的可生化性进行了分析,并时生物法在造纸废水中的应用情况进行了综述.     

Use of hydrogen peroxide detection strips to determine the extent of pasteurization in whole milk

Commercially available hydrogen peroxide (H₂O₂) detection strips were shown to be effective in determining known levels of H₂O₂ in milks where the lactoperoxidase system (LPS) had been inactivated. In addition, the strips were evaluated for determination of residual H₂O₂ in LPS-activated milks, following a range of heat treatments. The detection of residual H₂O₂ corresponded with results of zero lactoperoxidase activity. Hence, the detection strips offer a simple and accurate method for detecting the absence of lactoperoxidase, and therefore can be used to determine whether the milk has been subjected to overpasteurization. The technique provides a more convenient method than the standard procedure based on oxidation of 1,4-phenylenediamine.     

尿氧汽蒸煮漂工艺

本文提出使用尿素活化双氧水的煮漂工艺,以避免碱氧一浴汽蒸工艺使用较浓的烧碱所带来的一些弊病,使之更适用于涤富、涤粘以及麻类等对浓碱较敏感的织物前处理加工。文章介绍了该工艺的试验情况及用于实际生产的最佳工艺条件。尿氧汽蒸煮漂工艺加工织物的各项指标均能达到常规碱氧工艺水平,且节约用碱,降低消耗,经济效益明显。     

新型高分子氧漂稳定剂AR760稳定机理的研究

在研究新型氧漂稳定剂时,突破了以往稳定剂均采用镁盐的框架,提出了新的氧漂稳定剂AR760（PHA Sn~（4 ））,并对AR760的稳定机理进行研究,提出了胶团静电吸附模型。     

氧化预处理对羊毛品质及低温染色性能的影响

双氧水-甲酸体系是一种有效的羊毛溶胀体系.本文通过大量的试验,探讨了氧化预处理对羊毛染品的品质与染色性能的影响,肯定了通过该体系预处理实现羊毛低温染色的可能性.     

蚕蛹蛋白纤维过氧化尿素漂白研究

比较蚕蛹蛋白纤维过氧化尿素和过氧化氢漂白的H2O2消耗速率、pH值变化、白度和失重率,结果表明,过氧化尿素的漂白效果优于过氧化氢。     

Malondialdehyde Oxidation by Hydrogen Peroxide and by Light-Excited Riboflavin in Model Systems

Oxidation of malondialdchyde (MDA) by H₂O₂ was affected by concentrations of MDA or H₂O₂, pH and solvent. The reaction displayed an approximate 1:1 ratio of H₂O₂/MDA consumption and probably produced malonaldehyde as the oxidation product in moderate conditions. Oxidation of MDA by light-excited riboflavin produced superoxide anion, and the amount of superoxide anion generated was MDA concentration-dependent.     

废旧新闻纸浆与普通磨木浆混合H2O2单段漂白

本文对废旧新闻纸浆与SGW混合浆H2O2单段漂白的可行性进行论述,对其漂白工艺及影响因素进行分析。     

Towards the quantification of the effect of acid treatment on the heat tolerance of Escherichia coli K12 at lethal temperatures

The aim of this work is to investigate the effect of acid treatment -before and during heat inactivation- on the heat resistance of Escherichia coli K12 MG1655 cells at lethal temperatures. E. coli cells were grown in Brain Heart Infusion broth until they reached the stationary phase (≈10⁹ cfu/mL). Approximately 30 min before thermal inactivation the early stationary phase cells were added in Brain Heart Infusion broth with a specific pH value, achieved with addition of either acetic (50% (v/v)), lactic (50% (v/v)) or hydrochloric acid (30% (v/v)), and inactivation experiments took place at 54 °C and 58 °C. The inactivation dynamics are analysed using the inactivation model of Geeraerd et al. (2000). This enables to define the induced thermotolerance of E. coli as a prolongation of the shoulder and/or a reduction of the inactivation rate. Generally, addition of acids increased the heat resistance of E. coli. The induced resistance depends on the type of acid and on the quantity added, i.e. different levels of acidification lead to a different level of heat resistance.This work provides additional knowledge on the reaction of bacterial cultures to heat after acid treatment -before and during heat treatment- and, therefore, it contributes to an improved understanding of the effect of acid exposure on the bacterial heat resistance.     

双氧水净化回收淡碱的工艺研究与实践

印染厂淡碱回收净化十分必要,可采用双氧水净化的工艺,本文较详细地论述了双氧水净化的有关工艺条件及其各项指标的测定。通过大样实践证明采用此净化工艺具有操作简单、投资少、效果好的优点,是淡碱回收净化的一个新的途径。     

Prevention of the deterioration of polyphenol-rich beverages

Only a small amount of H₂O₂ was detected in beverages, such as tea or coffee, immediately after opening caps of bottles, but H₂O₂ was gradually produced in the beverages after opening the caps, i.e. exposure to air. The beverages with high concentrations of polyphenols showed high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities, but produced relatively high concentrations of H₂O₂ when they were exposed to air, possibly due to oxygen. The production of H₂O₂ increased both with duration of the exposure to air and rise in temperature. Since H₂O₂ is toxic, ways to prevent the deterioration of catechin-enriched green tea, i.e. H₂O₂ production, were studied. The addition of catalase, which is an enzyme decomposing H₂O₂, reduced the H₂O₂ concentration, but it was inactivated at a high temperature. The addition of l-cysteine or glutathione (reduced form), with a thiol residue, reduced the H₂O₂ concentration. Addition of citric acid, malic acid, succinic acid, fumaric acid, l-ascorbic acid, l-glutamic acid and l-aspartic acid also reduced it, possibly because they lower the pH of the tea.     

钛盐比色法测定消毒牛奶中残留过氧化氢的含量

介绍用钛盐比色法测定消毒牛奶中残留过氧化氢的含量。方法的检出限为0．36mg／L，回收率为78％～99％。     

活性染料染大豆蛋白纤维工艺

用过氧化氢对大豆蛋白纤维进行两次漂白,可得较佳之白度。大豆蛋白纤维在酸性条件下用活性染料染色,pH值控制在2－3左右,温度为85℃左右,染色效果较为理想。大豆蛋白纤维的碱性活性染料工艺,则pH值控制在10－11,温度为65℃左右,染色效果较好。     

PET瓶在热灌装饮料中的应用

通过PET的分子结构、物理／化学特性来说明影响PET瓶品质的物理、化学因素；通过PET瓶的生产工艺流程及热灌装PET的吹瓶方法／过程、及影响因素来说明PET瓶品质问题的产生原因及其解决方法；通过PET瓶在热灌装线的使用过程来说明影响PET热灌装饮料包装品质的因素及其解决方法；从而为PET瓶在热灌装线的使用提供了较有借鉴意义的一手资料。     

The first ESR observation of radical species generated under pulsed electric fields processing

Electron spin resonance (ESR) spectroscopy was used to investigate the generation of free radicals under pulsed electric field (PEF) processing. Spin trapping studies, using 5,5-dimethyl-1-pyrroline N-oxide (DMPO), showed the generation of hydrogen radicals in phosphate buffer and oleic acid emulsion. The concentration of hydrogen peroxide in phosphate buffer after PEF treatment was determined by spectrofluorometric method. Electric field strength has a significant effect on the concentration of H₂O₂ (p < 0.05). In PEF-treated samples with electric field strength of 30 kV/cm and 35 kV/cm, trace concentrations of H₂O₂ (0.177 × 10⁻⁶ and 2.035 × 10⁻⁶ mol/L, respectively) were detected.     

Application of decolorization on sugar beet pulp in bread production

The aim of this research is the examination of the decolorizing effect of hydrogen peroxide, on sugar beet fibers, which oxidizes the precursors of colored matter and the colored products from enzymatic reactions, by creating uncolored compounds. The advantage of hydrogen peroxide is that its surplus separates into water and hydrogen under the effects of temperature, light, and ions of alkaline and heavy metals and so, non-sucrose compounds do not get into the system. The color change of sugar beet dietary fibers is examined depending on the hydrogen peroxide concentration (in the range from 5 to 20 g H₂O₂/1,000 cm³), the pH value (in the range from 5 to 11), and the time of reaction (in the range from 1 to 12 h) at a temperature of 30 °C. To obtain the best effects of decolorized dietary fibers in white bread production the quality of the raw material is defined. The parameters for the preparation of the bread are chosen (the amount and particle size of the fibers, the amount of water and the mode of its addition) as are the additives, which results in good-quality white bread with sugar beet fibers.