Fe~(2+)和Fe~(3+)对长茎葡萄蕨藻生长、铁含量和生理特性的影响

【目的】探索两种无机铁对长茎葡萄蕨藻(Caulerpa lentillifera)的生长、铁含量及生理特性的影响。【方法】分别以三氯化铁(FeCl_3)和硫酸亚铁(FeSO_4)作为铁源,采用单因素实验方法,研究在不同浓度Fe~(2+)、Fe~(3+)条件下,长茎葡萄蕨藻的生长、光合色素含量、铁含量、两种过氧化酶(CAT、T-SOD)活性,以及总蛋白、维生素C和可溶性糖含量。【结果】在水体中无论是添加Fe~(2+)还是Fe~(3+),藻体的特定生长率(SGR)、光合色素含量、铁含量、过氧化物酶活性和维生素C含量均显著高于对照组(P <0.05)。藻体的铁含量随着培养液中铁离子浓度的升高而增加,以Fe~(2+)和Fe~(3+)处理后,藻体铁最高值分别可达到1 522.54μg/g和1 373.93μg/g,增幅为1 369.34%和1 225.92%;藻体维生素C最高质量分数分别可达15.41μg/mg和12.89μg/mg,增幅为107.56%和73.58%。Fe~(2+)实验组对藻体的可溶性糖含量有显著影响(P <0.05)。实验藻体的总蛋白含量显著低于对照组(P <0.05)。【结论】藻体在3 mg/L Fe~(2+)或者6 mg/L Fe~(3+)的条件下,长茎葡萄蕨藻生长最佳,其营养品质可得以改善。     

结晶紫分光光度法测定金矿贵、贫液中的金

利用结晶紫作为显色剂,乙酸丁酯萃取比色法(或目示比色法)测定金矿浸出液(贵液、贫液)中的金,可在1h内完成整个测定过程,该方法色阶明显,操作简便、快速,线性范围:0.0～4.0 mg/L.分析结果与原子吸收法的分析结果相符.可满足金矿贵、贫液中金的分析要求.该方法测定范围0.05～10.0 mg/L.     

全差示分光光度法测定地下水中微量酚

在PH10的碱性介质中,存在氧化剂铁氰化钾时,4-氨基安替比林与酚形成红色络合物,用三氯甲烷萃取比色测定酚,其检测限为0.002mg/l。但用二氯甲烷代替三氯甲烷萃取时,其检测下限可降低至0.0008mg/l。采用全差示分光光度法可进一步提高测定的灵敏度,其检测下限可降到0.00026mg/l。硫化物含量小于2.4mg/l时,对测定不干扰,可不预先蒸馏分离,而直接取样测定。     

吉林省夹皮沟—金城洞绿岩区中金矿床形成的物理化学条件

作者应用气液包裹体研究和热力学方法讨论了吉林省夹皮沟—金城洞绿岩区中金矿床形成的物理化学条件,分别确定了Ⅰ矿田(石(?)沟旷田)、Ⅱ矿田(夹皮沟矿田)和Ⅲ矿田(金城洞矿田)的成矿T、P、pH、Eh、fs_2、fo_2、fco_2及成矿溶液性质、成分类型、主要成矿离子Pb~(2+)、Zn~(2+)、Fe~(2+)、[AuS_3]~(3-)的浓度。     

在还原剂存在下Cr~(Ⅵ)的分光光度测定

本文研究在邻啡罗啉～氢氧化钠体系中,水样中含有S~(2-)、SO_3~(2-)、Fe~(2 )等还原剂与微量六价铬的共存条件和微量六价铬在24小时内不发生变化条件下拟定了正了醇萃取分离Fe~(2 )后,以二苯碳酰二肼光度法测定铬的分析方法,从而使分析水样保存简单,分析结果可靠。     

用黄药萃取分离后原子吸收光谱法测定矿石、土壤和有关物料中的钴、镍、铅、铋和铟

介绍一种测定矿石、土壤和有关物料中≥０．５μｇ／ｇ钻、镍和铅及≥３μｇ／ｇ铋和铟的方法。把样品分解并将其盐溶于稀盐醚－酒石酸溶液后，用抗坏血醚还原铁（Ⅲ），使产生的铁（Ⅱ）与氟化铵络合。在ＰＨ值２．００±０．０５下，用３倍的氯仿萃取其黄药络合物，使钴、镍、铅、铋和铟连续与铁、铝、锌和其它基体元素分离。用蒸发法除去氯仿并用硝酸和高氯醚破坏黄药后，把溶液蒸发至于，最后用乙炔焰原子吸收光诸法在含１００μｇ／ｍｌ钾的２０％Ｖ／Ｖ盐酸介质中测定各元素。在分解步骤时，用溴化物挥发法避免砷和锑共萃取。少量共萃取的相、铁和铜不会干扰。     

镁载体分离-丁基罗丹明B萃取光度法测定钽矿石中的钽

试样经碱熔融后,在高浓度钠盐存在的强碱性介质中,用镁作载体使钽沉淀完全而达到与钨、锡、钼、钒、硅等元素的分离,在硫酸介质中,钽与丁基罗丹明B形成红色络合物,用甲苯-丙酮混合萃取剂萃取,有机相在560nm处比色测定。其检出限:12×10-6五氧化二钽,测定范围:20×10-6～1.0×10-2五氧化二钽     

溶剂萃取原子吸收光谱法测定高纯石英砂中痕量铁

高纯石英砂用HF等溶剂溶解并蒸干后,在微酸性介质中用抗坏血酸还原Fe^3＋为Fe^2＋,与1,10-二氮杂菲形成Fe2＋3络合物,加入适量ClO4^-阴离子与之形成离子缔合物,用硝基苯萃取,原子吸收测定有机相,本法检出限1.1μg/g,样品分析结果的RSD%为：4.52～10.3.     

萃取分离硫代米氏酮目视比色法快速测定岩石矿物中的金

结合野外现场的条件,经试验提出了用甲基异丁基酮-异戊醇萃取分离,硫代米氏酮目视比色法快速测试地质样品中的金,该方法适宜于矿石中痕量金的测定,方法简便、实用、稳定,结果满意。     

宝石新宠——电气石的自述

正尊敬的人类朋友,我是最近几年涌现的颇受人类朋友喜爱的宝石新宠,我叫电气石,是电气石族矿物的总称,是以含硼为特征的铝、钠、铁、镁、锂、锰的环状结构硅酸盐矿物,分子式为NaR_5Al_6B_3Si_6O_(27)(OH)_4,R为Mg、Mn、Fe、Li、Al。以Fe~(2+)为主的称黑电气石,亦称铁电气石;以镁为主的称褐色镁电气石,呈玫红色、红色、蓝绿色、黄色和无色;以铝、锂为主的称锂电气石;以锰为主的称钠锰电气石。我(电气石)     

低值鱼蛋白多肽-铁(Ⅱ)螯合物的酶解制备及其抗氧化、抗菌活性

以南海低值鱼蛋白为原料,采用木瓜蛋白酶和风味酶的复合酶水解得到多肽水解物(HP),并制备多肽-铁(Ⅱ)螯合物,对螯合工艺及螯合产物的结果及抗氧化和抗菌功能特性进行了初步研究。结果表明:1)水解度为5%的多肽与铁(Ⅱ)螯合效果最佳,螯合率为94.15%;2)化学分析及红外光谱表明活性肽与亚铁离子螯合并形成稳定结构的螯合物;(3)经过50%乙醇(体积分数)沉淀的螯合铁具有明显的抗氧化活性,其抗氧化作用相当于维生素E的90%,经过80%乙醇(体积分数)沉淀的螯合物具有显著的抗枯草牙孢杆菌和金黄色葡萄球菌活性,其抑菌圈均直径为13mm。     

Membrane preconcentration of iron in seawater samples and on-site determination in spectrophotometry

A novel method for on-site determination of trace iron was developed using membrane preconcentration and spectrophotometric detection. Fe(Ⅱ)-ferrozine complex was reacted with cetyltrimethylammonium bromide (CTAB) to form a Fe(Ⅱ)-ferrozine-CTAB paired compound, which was collected on a membrane by filtration under vacuum. The membrane was immersed in 2 mL of ethanol-nitric acid and the absorbance of the solution measured for quantitative analysis. Various factors affecting the iron collection and determination were investigated. With different sample preconcentration volumes, the range of determination was broadened to 0.5-120 g/L. The detection limit of this method reached 0.19 g/L and the recoveries were between 97.2 and 109% when the concentration enrichment was about 45. The relative standard deviation (n = 7) was 1.9% for samples containing 10 g/L Fe. Twelve seawater samples were analyzed on-site using the proposed method, and two were also analyzed in inductively coupled plasma mass spectrometry. No significant difference was shown between the two methods by the Student’s t-test. The method has also been used on-site for iron enrichment experiments with phytoplankton and concluded to be simple, accurate and inexpensive.     

A Kinetic Spectrophotometric Method for the Determination of Iron (Ⅲ) in Water Samples

A new kinetic spectrophotometric method has been developed for the determination of iron (Ⅲ). The method is based on the catalytic effect of iron (Ⅲ) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium. The advantages of the proposed method are that it is sensitive, accurate, rapid, inexpensive, can be operated under room temperature and has a large determination concentration range compared to other techniques. The obtained optimum conditions are: pH 3.15, RAWL (200 mgL-1) 5.00mL, Potassium periodate solution (0.01 molL-1) 0.30mL, phenanthroline (0.02molL-1) 1.00mL, reaction temperature 25℃ and reaction time 7 miu. With this method iron could quantitively be determined in the range 0.00-0.02 mgL-1, the detection limit being 4.10×10-10mL-1. The relative standard deviations (RSD) in five replicate determinations for 3 μgL-1 and 5μgL-1 iron (Ⅲ) are 3.1% and 1.9%, respectively. The method has been applied to the determination of iron (Ⅲ) in tap water samples and seawater samples (from the South China Sea), the recovery rates being 98.0% and 100.5%, respectively.     

A Kinetic Spectrophotometric Method for the Determination of Iron （Ⅲ） in Water Samples

A new kinetic spectrophotometric method has been developed for the determination of iron (Ⅲ). The method is based on the catalytic effect of iron (Ⅲ) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium. The advantages of the proposed method are that it is sensitive, accurate, rapid, inexpensive, can be operated under room temperature and has a large determination concentration range compared to other techniques. The obtained optimum conditions are pH 3.15, RAWL (200 mgL-1) 5.00mL, Potassium periodate solution (0.01 molL-1) 0.30mL, phenanthroline (0.02molL-1) 1.00mL, reaction temperature 25℃ and reaction time 7 miu. With this method iron could quantitively be determined in the range 0.00-0.02 mgL-1, the detection limit being 4.10×10-10mL-1. The relative standard deviations (RSD) in five replicate determinations for 3 μgL-1 and 5μgL-1 iron (Ⅲ) are 3.1% and 1.9%, respectively. The method has been applied to the determination of iron (Ⅲ) in tap water samples and seawater samples (from the South China Sea), the recovery rates being 98.0% and 100.5%, respectively.     

Simultaneous determination of iron and manganese in water using artificial neural network catalytic spectrophotometric method

A new analytical method using Back-Propagation (BP) artificial neural network and kinetic spectrophotometry for simultaneous determination of iron and magnesium in tap water, the Yellow River water and seawater is established. By conditional experiments, the optimum analytical conditions and parameters are obtained. Levenberg-Marquart (L-M) algorithm is used for calculation in BP neural network. The topological structure of three-layer BP ANN network architecture is chosen as 15-16-2 (nodes). The initial value of gradient coefficient μ is fixed at 0.001 and the increase factor and reduction factor of μ take the default values of the system. The data are processed by computers with our own programs written in MATLAB 7.0. The relative standard deviation of the calculated results for iron and manganese is 2.30% and 2.67% respectively. The results of standard addition method show that for the tap water, the recoveries of iron and manganese are in the ranges of 98.0%-104.3% and 96.5%-104.5%, and the RSD is in the range of 0.23%-0.98%; for the Yellow River water (Lijin district of Shandong Province), the recoveries of iron and manganese are in the ranges of 96.0%-101.0% and 98.7%-104.2%, and the RSD is in the range of 0.13%-2.52%; for the seawater in Qingdao offshore, the recoveries of iron and manganese are in the ranges of 95.3%-104.8% and 95.3%-104.7%, and the RSD is in the range of 0.14%-2.66%. It is found that 21 common cations and anions do not interfere with the determination of iron and manganese under the optimum experimental conditions. This method exhibits good reproducibility and high accuracy in the determination of iron and manganese and can be used for the simultaneous determination of iron and manganese in tap water and natural water. By using the established ANN- catalytic spectrophotometric method, the iron and manganese concentrations of the surface seawater at 11 sites in Qingdao offshore are determined and the level distribution maps of iron and manganese are drawn.     

化学发光分析法测定铁的进展

综述了化学发光分析测定铁的进展 ,叙述了化学发光法测定铁的基本原理、所用的化学发光试剂、影响因素及测定方法。初步探讨了铁的化学发光机理。     

Studies on culture conditions of benthic diatoms for feeding abalone

Effects of iron and silicon nutrients and of orthogonal combinations of nitrogen, phosphorus, iron and silicon on the growth rate of three benthic diatoms were studied by using an in situ OD measurement method. The results of monofactor tests of iron and silicon showed that Fe-EDTA was better than ferric citrate in the culture of these diatoms; that the favourable concentration of Fe-EDTA was about 0.5 mg/L of Fe and that of silicate was 2.5 mg/L of Si or more. The orthogonal test showed that the optimal concentration ratios (mg/L) of nitrogen, phosphorus, iron and silicon were: 5.0: 0.25: 0.5: 2.0 forCocconeis scutellum var.parva; 2.5: 1.0: 1.0: 2.0 forAmphora coffeaeformis; and 5.0: 0.15: 0.5: 2.0 forN. mollis. Project 39470065 supported by NSFC.     

STUDIES ON CULTURE CONDITIONS OF BENTHIC DIATOMS FOR FEEDING ABALONE Ⅲ. EFFECTS OF IRON AND SILICON NUTRIENTS AND OF ORTHOGONAL COMBINATIONS OF NITROGEN,PHOSPHORUS,IRON AND SILICON ON GROWTH RATE

rmDUCnONInthecultUreofbenthicdiatomsasfeedforabalone,itisnecesoptoaddsomnu-trientssuchasnitIngen,Phosphorus,ironandsilicontotheSeawatermwhum.Thecom-monraioofthenutrientswas(lO-25):(l-2.5):o.l:l(mg/L)(Chenetal.,1977).Anstinetal-(l99o)rePOrtedthatheratioofnibogenandphosphorusinfluencedthebio-massdensityofthePeriphyton,whichInainlyconsistedOfbenthicdiatomPOPulations.However,theirrestiltswerenotbasedonmonoalgalwwh,andtherewerenodetallsonthereasonableratioofthesenutrientsintheirreports-Ther…     

静态GPS在角峪铁矿普查控制测量中的应用

角峪铁矿普查项目采用现代大地测量的方法,利用已知的3个D级GPS点,以E级GPS控制网作为测区首级控制网,选用6个E级点构成骨架网,按照GPS网的效率、可靠性、精度,进行优化设计。在四等水准点的基础上,高程测量采用GPS拟合高程的方法。结果表明,应用此方法构造的E级控制网,精度完全符合矿区普查的需要。     

Factors controlling the distribution of transitional metal elements in marine hydrogenic ferromanganese crusts

A series of selective dissolution experiments were conducted on the hydrogenic ferromanganese crusts collected near Line Island to study the geochemistry of Mn, Fe, Cu, Co, Ni and Ti. Despite of the fact that the very close intergrowth between amorphous ferric oxyhydroxides and δ-MnO2 exists in the hydrogenic ferromanganese crusts, there is no isomorphous substitution between iron and manganese. This is because the two elements in oxides have different crystal chemistry and geochemistry, such assertion bein...