过硫酸钾氧化-氨性液分离-钼蓝抗坏血酸还原分光光度法测定海带中微量磷的研究

海带中微量磷的测定,尚未见报道。样品以硝酸-高氯酸分解、氨水调节体系呈微碱性,除去可能含有的金属杂质后,过硫酸钾氧化各种形式的磷盐成正盐,因此,在钼蓝-抗坏血酸还原体系基础上,建立了分光光度法测定微量磷的新方法。磷含量在0～2.0ug/50ml范围内具有线性关系,CV%=97%～101%,RSD%=1.06%～1.20%,Sandell=2.0×10-3ug.cm-2。实际样品分析,结果满意。     

植物油精炼过程中微量成分变化

<正>植物油除主要成份-甘油三酯外,还含有磷酯、甾醇、色素、生育酚、游离脂肪酸等微量物质,这些微量物质会对植物食用油品质和贮存稳定性产生较大影响。本文拟对上述五种微量物质在油脂精炼加工过程中变化作一初步探讨。     

粮食中微量磷测定方法的工艺分析

采用分光光度法对玉米中微量磷的测定进行了研究,并对其影响因素、结果进行分析和探讨,通过单因素试验和正交试验确定其最佳条件为:测量波长为418nm、改进剂用量10mL、分解液放置的时间12min、样品粒度40目.用方差分析和回收率实验证明该方法简单方便,可广泛用于粮食中微量磷的测定.     

精炼对菜籽油品质的影响

菜籽油精炼过程是一个发生物理与化学变化的过程,在这一过程中,菜籽油损失了一些天然的微量物质,也引入或产生了多种其他微量物质,而这些微量物质的变化对菜籽油的品质具有决定性影响.对国内6厂家生产的菜籽油进行取样,选取酸值、过氧化值、磷含量、色泽、生育酚含量、植物甾醇含量、反式酸含量这几类对菜籽油品质影响较大的微量物质,对其进行分析测定,以期得到菜籽油精炼各工序中这些微量物质的变化规律,为菜籽油的适度精炼提供依据.     

钼－硫氰酸盐－吐温－60光度法间接测定食品中微量磷

钼－硫氰酸盐－吐温－６０光度法间接测定食品中微量磷杜斌，魏琴，于京华，罗川南（山东建材学院应用化学系，济南，２５００２２）食品中的磷具有营养学的意义，磷含量的测定是食品分析的一项检验指标。光度法是测定微量磷的常用方法，常见的有磷钼蓝法、锑磷钼蓝法和磷...     

磷-钼酸铵-孔雀绿-聚乙烯醇光度法测定食品中微量磷

磷－钼酸铵－孔雀绿－聚乙烯醇光度法测定食品中微量磷魏要武喻利娟（南通市卫生防疫站，南通２２６００６）０前言食品中磷含量是一个重要的营养学指标。通常微量磷的测定采用钼蓝比色法［１］，该法稳定性较差，并因其还原剂需在使用前配制，使实验费时、繁琐。作者对酸...     

影响SBR除磷率相关因素的探讨

SBR是序批式活性污泥法的简称,其主体构筑物是SBR反应池。随着洗涤剂的大量使用,磷造成的水体富营养化现象日益严重,而磷的去除率是污水处理是否达标的关键性指标。就SBR除磷率的影响因素进行了论述与探讨。     

新时代 智能洗衣让生活更轻松

小天鹅TD70-1202LPID(L)滚筒洗衣机小天鹅TD70-1202LPID(L)滚筒洗衣机的自动投放系统能在洗涤过程中,根据衣物重量、洗衣程序等因素,自动添加相应剂量的液体洗涤剂和柔顺剂,在有效解决因洗涤剂过度使用造成衣物损伤的同时,减少了污水排放,将洗衣机的智能化升级到一个全新标准。通过采用自动投放技术,小天鹅自动投放洗涤剂洗衣机做到了洗涤剂的科学精准投放,避免了用户误     

关于无磷洗衣粉的研究分析

洗衣粉是我们日常生活经常会用到的洗涤用品,其属于合成洗涤剂的一种,以表面活性剂为其主要成分,同时还有适量的助洗剂。是在洗涤剂的基础上进行完善而形成的,更易于人们将衣服清洗干净的粉状洗涤剂。文中对洗衣粉中含磷成分的性能进行了分析,并进一步对洗衣粉中的代磷助剂进行了具体的阐述。     

无患子皂苷-纳米银抑菌洗涤剂的制备及其抑菌性能研究

本研究首次制备出无患子皂苷-纳米银抑菌洗涤剂,并借助紫外-可见分光光谱(UV-Vis)、透射电子显微镜(TEM)考察了纳米银的粒径、洗涤剂中主要活性成分脂肪醇醚硫酸钠(AES)与脂肪醇聚氧乙烯醚(AEO-9)对纳米银的影响,最后通过平板计数法研究了纳米银颗粒及无患子纳米银抑菌洗涤剂对金黄色葡萄球菌的抑菌性。结果表明:TEM图表明纳米银的粒径在10~15nm之间;洗涤剂中纳米银仍保持较好的稳定性;当纳米银的浓度为2.5mg/L时,对金黄色葡萄球菌的抑菌率为100%;配制的碱性及酸性无患子纳米银洗涤剂对金黄色葡萄球菌的抑菌率分别为56.5%和60.0%。     

Analysis of Isinglass Residues in Beer

A method has been developed for the detection of trace quantities of residual isinglass present in fined beers. Isinglass residues in beer are concentrated by means of an antibody raised using isinglass as an antigen. The separated isinglass is hydrolysed to its constituent acids and quantified by measuring the content of hydroxyproline. The limit of quantification of this method, that is the concentration of isinglass in beer which can be distinguished from background levels of hydroxyproline, is 0.17 mg of isinglass/litre of beer (on an isinglass dry weight basis). This method has been used to quantify the concentration of isinglass residues which could be present in brewery and cask conditioned beers, and also to determine whether there is likely to be stratification of isinglass residues in casks.     

微波消解-电感耦合等离子体发射光谱法同时测定赣南脐橙中硅铝铁钙镁钾钠磷硫

选用硝酸和过氧化氢的混合消解液对脐橙进行封闭微波消解,利用电感耦合等离子体发射光谱仪(ICP-AES)直接测定脐橙中微量硅、铝、铁、钙、镁、钾、钠、磷、硫的含量。该方法检出限符合规范要求,方法回收率94.0%～107.0%,相对标准偏差(RSD)<5%。该方法具有良好的准确度和精密度,且溶样过程无污染,方法简便、快速。     

Life cycle assessment (LCA) of cleaning-in-place processes in dairies

Four Cleaning-In-Place (CIP) methods for dairies were compared using life cycle assessment (LCA). The methods were conventional alkaline/acid cleaning with hot water disinfection, one-phase alkaline cleaning with acid chemical disinfection, enzyme-based cleaning with acid chemical disinfection and the conventional method with disinfection by cold nitric acid at pH 2. Production of detergents, transport, the user phase in the dairy and waste management of containers were included. The user phase was found to be the most important part of the life cycle. The CIP methods with small volumes and low temperatures, such as enzyme-based cleaning and one-phase alkaline cleaning, turned out to be the best alternatives for the impact categories energy use, global warming, acidification, eutrophication and photo-oxidant formation. Milk residues flushed out in the rinsing phase were the main contributor to eutrophication, but the phosphorus and nitrogen in the detergents also influenced the results. Evaluation of toxic substances poses a methodological problem in LCA. In this study, detergents partly composed of toxic substances were included, and the overall assessment was that the one-phase alkaline cleaning method was preferable from an environmental point of view. A qualitative assessment of toxicity was performed.     

Removal of lead contaminated dusts from hard surfaces

Government guidelines have widely recommended trisodium phosphate (TSP) or "lead-specific" cleaning detergents for removal of lead-contaminated dust (LCD) from hard surfaces, such as floors and window areas. The purpose of this study was to determine if low-phosphate, non-lead-specific cleaners could be used to efficiently remove LCD from 3 types of surfaces (vinyl flooring, wood, and wallpaper). Laboratory methods were developed and validated for simulating the doping, embedding, and sponge cleaning of the 3 surface types with 4 categories of cleaners: lead-specific detergents, nonionic cleaners, anionic cleaners, and trisodium phosphate (TSP). Vinyl flooring and wood were worn using artificial means. Materials were ashed, followed by ultrasound extraction, and anodic stripping voltammetry (ASV). One-way analysis of variance approach was used to evaluate the surface and detergent effects. Surface type was found to be a significant factor in removal of lead (p < 0.001). Vinyl flooring cleaned better than wallpaper by over 14% and wood cleaned better than wallpaper by 13%. There was no difference between the cleaning action of vinyl flooring and wood. No evidence was found to support the use of TSP or lead-specific detergents over all-purpose cleaning detergents for removal of lead-contaminated dusts. No-phosphate, non-lead-specific detergents are effective in sponge cleaning of lead-contaminated hard surfaces and childhood lead prevention programs should consider recommending all-purpose household detergents for removal of lead-contaminated dust after appropriate vacuuming.     

不同洗涤方法对果蔬中农药残留去除率的研究

建立了果蔬洗涤剂对农药残留去除率的测定方法。用喷洒法分别污染果蔬,经乙腈提取,固相萃取(SPE)富集净化后,再用气相色谱-质谱法(GC-MS)测定农药残留。此方法简单易操作,可用于评价各类厨房用洗涤剂去除农药的效果。     

洗涤中氧化作用和机械冲击对织物强度的影响

为了解家用洗涤过程中含漂白剂洗衣粉对织物的损伤情况,借鉴AATCC快速洗涤测定织物色差的方法,研究机械冲击力和氧化双重作用下,棉织物强度的损伤特性.实验表明,在没有机械冲击作用的情况下,含漂白剂的洗衣粉要比普通洗衣粉损伤大,但是在有机械力存在的情况下,洗涤过程中洗衣粉中的氧化剂给予织物的额外损伤将变得不明显,这说明在洗衣粉中添加氧化剂或洗涤过程中添加氧化漂白成分,其化学损伤可以被机械损伤掩盖.     

微波消解-原子吸收光谱法测定昭平绿茶中微量元素

茶叶中微量元素的含量分析是茶叶科学的重要研究内容之一,其含量高低对茶叶品质影响较大,因此,有必要对茶叶中的微量元素进行测定。研究建立了以HNO3-H2O2为消解液进行微波辅助消解样品,火焰原子吸收光谱法测定绿茶中铜、铁、锌微量元素含量的方法。实验采用程序升温的方式进行样品消解,回收率高,并且对三种绿茶样品测定结果进行了比较分析。回收率在93.6%101.5%之间,RSD在0.58%3.16%之间;样品中微量元素含量分别为Fe:98.95 177.8μg/g,Zn:45.67 59.29μg/g,Cu:19.7724.22μg/g。此方法测定茶叶中微量元素,可靠、灵敏度高,选择性好,方法简便,且对环境友好,适合常规分析。     

微波消解光度法测定奶粉中的磷

样品预处理在分析测定过程中具有十分重要的作用。本研究探讨了一种新兴的样品预处理方法--微波消解法在奶粉分析中的应用。考察了微波消解时溶剂的用量、消解液体积、消解时间、功率和压力对消解效果的影响,选择了微波消解的最佳工作参数。与传统方法相比,该方法具有省时、省酸,操作简单,减少沾污,改善工作环境等优点,是一种有效的实用方法。     

不同预处理方法减少食品中二氧化硫残留量比较的研究

采用碘吸收滴定法测定了几种食品中二氧化硫的残留量及比较了不同预处理方法对二氧化硫含量的影响。以白木耳,笋衣为原料,采用GB/T 5009.34的改进方法测定食品中二氧化硫残留量,比较了25℃自来水浸泡、煮沸法、小苏打浸泡法,60℃热水浸泡法及醋酸浸泡法对样品中二氧化硫含量的影响。五种方法中除醋酸浸泡法减少样品中二氧化硫的效果最差,其余4种方法均能有效地降低食品中二氧化硫的残留量,其中沸水煮沸20min后能完全驱除二氧化硫,该方法简便、实用且易于操作;其次是60℃水浴3h,然后是0.5%小苏打溶液浸泡5 6h和25℃自来水浸泡处理5 6h。     

磷钼蓝分光光度法测定果蔬中有机磷农药

将磷钼蓝分光光度法中的还原剂改进为苯酚,采用苯酚还原磷钼蓝分光光度法测定果蔬中的总磷、无机磷,从而得出有机磷含量。实验表明,该方法最大吸收波长为810nm,磷含量在0～40μg范围内,符合比耳定律,标准曲线的回归方程为y=0.0161x＋0.0008,相关系数R2=0.9965,表观摩尔吸收系数为2.8×105L.mol-.1cm-1,与标准法相比,相对偏差为2.21%～4.47%,回收率在93.10%～102.26%之间。