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钢铁中磷的测定目前多采用磷钼蓝光度法及磷钒铝黄光度法,但前者的吸光度稳定时间短,不适用于成批试样的分析;后者的吸光度稳定时间虽然较长但灵敏度低。文献报道了孔雀绿-钼磷杂多酸光度法测定矿石中微量磷的条件,指出此法灵敏度比磷钼蓝光度法高,吸光度24小时不变。本文研究以孔雀绿-磷钼杂多酸光度法则定钢铁中磷的条件,表明,在0.28— 相似文献
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高纯碳酸锂中痕量磷,砷的孔雀绿—磷(砷)酸钼浮膜分光光度法测定 总被引:1,自引:0,他引:1
本文研究了孔雀绿与磷(砷)酸钼离子对膜的形成条件,并依此与基体分离,进行痕量磷,砷的浮膜-分光光度法测定。选用硫酸为介质,考察了25种共存离子对测定的影响。拟定了高纯碳酸锂中痕量磷,砷的分析方法,操作简便,结果令人满意。 相似文献
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生铁和铸铁中磷的测定 总被引:2,自引:0,他引:2
严钊 《理化检验(化学分册)》1999,35(4):187-187
生铁和铸铁中磷的含量在ω_90.3%以下,通常采用氟化钠—氯化亚锡还原钼蓝法及抗坏血酸还原磷钼蓝法进行测定。该两方法的缺点为钼蓝色泽不稳定和重现性差。锑磷钼蓝法灵敏度高、稳定性好,但通常采用该方法进行痕量磷的测定。本文对该方法加以改进测定生铁及铸铁中磷,经改进后方法测定范围从0.01%~0.06%扩大到0.01%~0.32%。试验结果表明,该法简便、准确,显色液稳定时间达到5h以上。 1 试验部分 1.1 主要试剂 磷标准溶液:100μg·ml~(-1),称取基准磷酸二氢钾0.4393g溶于水中并稀释到1L。使用时稀释成4μg·ml~(-1)标准工作溶液。 硝酸-盐酸混合液:硝酸和盐酸(1+2)混合 相似文献
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磷的测定方法有磷钼杂多酸法、磷钼蓝法、钒一钼酸铵法、磷锑钼蓝法等。本法研究了在硫酸介质中,磷与适量的钼酸根形成磷钼杂多酸络阴离子[P(Mo3O10)4]^3-,再与罗丹明B阳离子(RDB)。形成离子缔合物(RDB)3[P(Mo3O10)4]直接水相光度法测定磷。结果表明,该体系灵敏度较高,稳定性好,且操作简便,重现性好,适用于各种水样中微量磷的测定,结果满意。 相似文献
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钼-锑-TritonX-100-钛体系中双波长法同时测定低含量的硅酸盐和磷酸盐 总被引:3,自引:0,他引:3
文献已报导了在高氯酸介质中选择适当条件使硅酸盐不完全显色用双波长法测定高硅样品中的痕量磷。由于硅钼兰和磷钼兰的最大吸收仅差15nm,灵敏度较低。本文根据硅酸盐和磷酸盐能在钼-锑-tritonX-100-体钛系中形成最大吸收相差110nm的稳定络合物以及双波长法原理,利用220A型分光光度计的多波长扫描程序,在三个波长下测定,一次比色同时获得硅磷两元素的结果。加之两种钼蓝均能室温显色,手续非常简便。本文采用抗坏血酸加 相似文献
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磷钼蓝光度法已广泛用于地质试样中磷的测定。但发色速度受温度的影响颇大,一般需加热,显色酸度也较严,稍不注意,游离的钼酸盐被还原而造成测定失败。本文采用抗坏血酸-锑-钼酸盐-酸羟胺组成的混合试剂作为磷的显色剂,可在室温下使磷迅速发色,而且显色后96小时内络合物的吸光度不变。由于在显色剂中引入了较多的盐酸羟胺,有效地抑制了游离钼酸盐的还原,故磷钼蓝的颜色纯且稳定。 相似文献
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土壤速效磷的流动注射光度分析 总被引:1,自引:0,他引:1
磷作为作物生长发育必需的营养元素 ,历来被作为土壤肥力水平高低的标志之一。发达国家几乎每年都对土壤的养料状况进行测定 ,根据测定值及土壤与气候条件制订施肥建议。而土壤中速效磷的测定通常采用NaHCO3提取 ,磷钼蓝法和磷钼蓝萃取分光光度法[1 ] 测定。也有采用阴离子交换树脂提取法和同位素交换法[2 ] 。同位素交换法不适于测定高固磷土壤 ,分光光度法手工操作 ,耗时长 ,也不能实现自动分析。本文采用乙基紫 钼酸铵 OP络合显色的反应体系[5,6] ,流动注射分析技术 ,确立了土壤中速效磷的快速自动分析方法。用于实际样品分析 ,结… 相似文献
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以杂多酸形式光度法测定磷的进展 总被引:4,自引:0,他引:4
磷的测定方法中,目前光度法所占的比例还比较大。分析化学工作者已对磷钼二元杂多酸、磷钼二元杂多酸与另外一些元素形成的三元杂多酸的反应机理及光度法测定磷的分析应用进行了广泛研究,使得以磷钼杂多酸形式光度法测定磷比较成熟和普及。这类方法简单准确、使用方便、易于实现自动化、不仅用于痕量也用于高含量磷的测定。 相似文献
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吸光光度法测定磷 ,无论是磷钼黄法还是磷钼蓝法 ,或是磷钒钼三元络合物法 ,都要求磷以正磷酸分子参加化学反应 ,所以把磷的各种低价化合物氧化为五价的正磷酸是光度法测定磷的首要条件。如不少分析方法中测定铜合金中磷也采取了用各种氧化剂氧化磷呈正磷酸尔后测定。测定磷铜中间合金中磷 ,文献 [1~ 3]均采用磷钒钼三元络合物方法 ,该法简单、快速、准确、重复性好 ,倍受分析工作者欢迎。分析方法采用混合酸(HNO3∶HCl∶H2 O =32 0∶12 0∶5 6 0 )溶样 ,滴加H2 O2 氧化磷 ,加HClO4 冒烟使磷进一步完全氧化为正磷酸 ,再进行… 相似文献
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共振瑞利散射法测定硫氰酸盐-碱性三苯甲烷染料体系中的痕量钼 总被引:11,自引:0,他引:11
研究了钼(Ⅴ)与硫氰酸盐和结晶紫、乙基紫、孔雀石绿、亮绿及碘绿等5种碱性三苯甲烷染料形成离子缔合配合物的共振瑞利散射光谱。考察了它们的光谱特征、影响因素和适宜的反应条件,确定了共振瑞利散射强度与钼(Ⅴ)浓度之间的关系。方法灵敏度高,不同体系对钼的检出限在2.1~12.0μg/L之间,提出了用共振瑞利散射测定钼的新分析方法,将其用于钢铁中痕量钼的测定获得满意的结果。 相似文献
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The formation of an ion-associate between vanadomolybdophosphate and malachite green in aqueous acidic solution (0.5 M sulfuric acid) enables trace amounts (0?1 × 10?5M) of phosphate to be determined. The molar absorptivity is 1.05 × 105 l mol?1 cm?1 at 620 nm. The complex was stabilized in solution by adding poly (vinyl alcohol). Other ions generally found in river waters did not interfere. Interference by silicate is less than that found in the corresponding malachite green molybdophosphate procedure; interference of arsenate is avoided by reduction with thiosulfate. The method is applied to the determination of μg l?1 amounts of phosphorus in river water; the results obtained were in good agreement with those obtained by an extraction-spectrophotometric method with malachite green. 相似文献
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Aneta Jastrzębska 《Chemical Papers》2009,63(1):47-54
Spectrophotometric determination of total phosphorus in meat samples was modified using the molybdenum blue reaction with
the following reducing agents: ascorbic acid (AA), hydrazine sulphate (HS), and mixture of hydroquinone and hydrazine sulphate
(HHS). Proposed methods were validated by evaluation of statistical parameters such as: linearity, sensitivity, limits of
detection (DL) and quantification (QL), precision, and accuracy, against the standard and malachite green (MG) modified procedures
and by applying food certified materials. The values of within-day and between-days precision in meat samples for all tested
reducing agents were better than 3.4 % and 4.2 %, respectively. The recoveries for CRMs analyses were between 92 % and 102.3
%. Obtained results suggest usefulness of the hydroquinone and hydrazine sulphate mixture in the determination of phosphorus
ions. 相似文献
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An improved method for the spectrophotometric determination of phosphorus in steel has been described. Reduction of the phosphomolybdate complex with ascorbic acid and antimony has been found to be advantageous over other methods. No heating is necessary for the formation of the complex and it is stable for more than 24 hr. The “molybdenum blue” formed shows maximum absorption at 882 nm and the molar extinction coefficient is 25,670. The method has been found useful for the determination of microquantities of phosphorus in steel. 相似文献
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Summary The visual method proposed here for the determination of phosphate ion in environmental water samples does not need any instrument. The highly sensitive method is based on the observation of the blue color produced as the result of ion association of phosphomolybdate and malachite green in acidic medium. Down to 10 ppb of phosphate-phosphorus can be determined by addition of 1 ml of reagent solution to 4 ml of sample in a test tube. The method has been effectively used for the determination of phosphate ion which is a nutrient for phytoplakton in brackish lakes and rivers.
Einfaches visuelles Verfahren zur Phosphorbestimmung in Umwelt-Gewässern相似文献
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本文报道了孔雀石绿-聚氯乙烯膜涂层玻璃电极的研制及其应用。该电极是将孔雀石绿敏感的聚氯乙烯膜涂敷于pH玻璃电极表面而制得。所制电极具有制作简单,使用方便,响应灵敏度高,选择性好等优点。能够直接用于孔雀石绿的测定。本文将该电极应用于催化电位法分析,测定了几种环境水样中亚硝酸根的含量,结果满意。 相似文献
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Chemiluminescence Determination of Molybdenum by on-Line Reduction with a Flow Injection System 总被引:2,自引:0,他引:2
Zhi Jia ZHU 《中国化学快报》2000,41(5)
ThereactionsofLuwithhydrogenperoxidecatalysedbymetalionsandalsoreactionofLuwithorganicreductantssuchasglucoseandascorbicacidhavebeenreported"=.OurrecentstudiesshowedthatsomeinorganicreductantssuchasMo(Ill),V(11),U(ill),W(ill),Cr(II),Ti(ill)andFe(11)etc.canreactwithLuinstrongalkalinemediumtogenerateCL.Inthispaper,theCLreactionbetweenLuandMo(ill)producedbyaJonesreductor3hasbeenstudiedindetailforthefirsttime,andtheCLreactionhasbeensuccessfullyappliedtodeterminemolybdenumwithexcellentsensi… 相似文献
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The paper describes a novel method for copper preconcentration using microcrystalline triphenylmethane loaded with malachite green prior to the determination by the flame atomic absorption spectrometry (FAAS). Under the optimum conditions, Cu(Ⅱ) can be totally adsorbed on the surface of microcrystalline triphenylmethane, and completely separated from Pb(Ⅱ), Cd(Ⅱ), Co(Ⅱ), Cr(Ⅲ), Ni(Ⅱ), Mn(Ⅱ), Fe(Ⅲ) and Al(Ⅲ) by controlling acidity. The preconcentration factor of this proposed method is 200. The recovery is in a range of 97.5%-105%. The relative standard deviation (RSD) is not beyond 3.0%. The proposed method has been successfully applied to the determination of trace copper in various water samples with satisfactory results. 相似文献