ICP—OES同时测定三元复合肥中六种微量元素

用微波消解／电感耦合等离子体发射光谱法（ICP—OES）同时测定了三元复合肥中的铜、铁、锌、镍、锰、钼6种微量元素。结果表明,该法具有简便、快速、结果可靠、检出限低、良好的精密度、精确度、高回收率以及能够同时测量多种元素的优点;通过对比实验测量得到了有效态微量元素的浓度和微量元素的总量,结果显示大部分微量元素是以有效态形式存在于复合肥中。因此,该法可以作测量复合肥类产品中的微量元素的一种参考使用方法。     

自动电位滴定法快速测定钾盐中的钾含量

钾含量的测量常用火焰光度法和四苯硼钾重量法。火焰光度法适用于微量分析 ,对较高含量钾的测定误差较大 ,四苯硼钾重量法的测定准确度高 ,但操作繁琐 ,测定周期长 ,易出错。本文采用四苯硼钠溶液电位滴定法 ,测定高、中含量组分钾 ,测定周期短 ,所用试剂少 ,且不受样品中水不溶物的干扰 ,选择性好 ,测定的准确度和精密度均在 0 .2 %以下 ,适用于钾盐、卤水、复合肥和钾肥中钾的测定。1　实验部分1 .1　仪器和药品ZD 2型自动电位滴定仪 (上海雷磁仪器厂 ) ,PK 1型钾离子选择电极 ,2 1 7型饱和甘汞电极 (双盐桥 )。四苯硼钠标准液 :0 .1mol…     

章鱼肉碱标准样品的研制

研制了章鱼肉碱标准样品。以章鱼加工副产物为原料,通过提取、分离纯化制备高纯章鱼肉碱,采用红外光谱(IR)、高分辨质谱(MS)和核磁共振谱(NMR)进行结构确证。样品分装成144瓶,采用离子色谱检测法进行均匀性、稳定性检验和定值分析。从样品中随机抽取15瓶进行均匀性检验,经F检验表明:在95%的置信区间内样品均匀性良好。在0~4℃条件下,经过24个月长期试验稳定性考察,结果表明样品稳定性良好。标准样品经国内8家具有分析资质的实验室进行协同定值,章鱼肉碱标准样品定值结果为99.49%,相对扩展不确定度为0.14%(k=1.96)。该标准样品达到标准样品的技术要求,可用于章鱼肉碱相关产品的质量控制和分析方法校正。     

近红外漫反射法快速检测复合肥中总氮含量

本文采用数字光栅近红外漫反射技术对复合肥中总氮(N)含量进行测定,以采用标准正态变量转换、趋势变换、导数变换等方法对180个正常复合肥的近红外测量数据进行前处理,然后采用偏最小二乘回归校正方法(MPLS)建立模型,取得对未知复合肥中总氮含量较好的预报结果。该方法优势:(1)检测省时,往往只需几分钟即可完成分析,而且无需称样和消耗化学试剂。(2)其测定标准偏差与凯氏法相比不存在显著性差异。该新方法可对复合肥中总氮含量实现快速简便的连续检测,尤其适合大批量样品。     

蜂王浆冻干粉中甲硝唑残留标准样品制备的研究

建立了蜂王浆冻干粉中甲硝唑残留标准样品的研制和定值方法。对日常检测阳性样品进行匀浆、冷冻干燥和均匀化加工处理,真空包装,得到1批400袋蜂王浆冻干粉样本。F检验法和t检验法表明在95%置信区间内,样本均匀性、短期稳定性和长期稳定性均达到标准样品要求。制备的甲硝唑标准样品采用液相色谱-串联质谱法,与国内外8家实验室进行协同定值。采用格拉布斯和柯克伦检验对定值结果进行异常值检验,并对结果进行不确定度评估。     

临床实验室标准物质氯化钠的研究与测定

用重量法测定氯化钠中的钠含量(Na_实~+/Na_理~+),测定值为99.97％,标准偏差0.02％,总不确定度0.04％,并作了样品的均匀性、稳定性检验。用精密摩仑滴定法测定氯化钠中氯的含量(Cl_实~+/Cl_理~+),测定位99.993％,标准偏差0.005％,并作了样品的均匀性检验。结果表明,氯化钠中钠和氯的含量均符合临床实验室标准物质技术规范要求,达到国际同类标准物质先进水平。     

聚-4-氧杂-6,7-双甲硫基庚基硅氧烷铂络合物的合成及其对烯烃硅氢加成反应的催化特性

4-氧杂-6,7-双甲硫基三甲氧基硅烷用气相法二氧化硅固载,再与氯亚铂酸钾作用,合成了双齿型硫醚铂络合物——聚-4-氧杂-6,7-双甲硫基庚基硅氧烷铂络合物。它对烷氧基硅烷与烯烃的硅氢加成反应具有良好的催化活性和突出的回收再用性能。其结构通过元素分析和XPS进行了表征。     

硫酸氨基葡萄糖标准样品的研制

研制了硫酸氨基葡萄糖标准样品。以盐酸氨基葡萄糖为原料,制备高纯硫酸氨基葡萄糖,采用红外光谱(IR)、高分辨质谱和核磁共振谱(NMR)进行结构确证。样品分装成200瓶样品后,采用高效液相色谱–蒸发光散射法进行均匀性检验、稳定性检验和定值分析。从样品中随机抽取15瓶进行均匀性检验,结果表明在95%的置信区间范围内样品均匀性良好。按照25℃长期试验稳定性(12个月)进行稳定性考察,结果表明在考察期间内样品稳定性良好。标准样品经国内8家具有分析资质的实验室进行协同定值,硫酸氨基葡萄糖标准样品定值结果为99.84%,相对扩展不确定度为0.18%(k=1.96)。该标准样品达到国家标准样品的技术要求,可用于有关硫酸氨基葡萄糖的分析方法校正和质量控制。     

含铅黄铜儿童仿真饰品标准物质的研制

4介绍含铅黄铜儿童仿真饰品标准物质的研制方法。以铜锭、锌锭、铅粒为原料,利用坩埚熔炼及模具加工制备黄铜儿童仿真饰品标准物质,采用电感耦合等离子体发射光谱法进行均匀性检验、稳定性检验和定值。从样品中随机抽取15份进行均匀性检验,经F检验表明在95%的置信区间内样品均匀性良好。在常温条件下,经过12个月长期稳定性试验考察,结果表明样品稳定性良好。铅含量定值结果为136.1 mg/kg,合成扩展不确定度为0.72 mg/kg(k=2)。该标准物质满足ISO Guide 35:2006技术要求,可用于黄铜儿童仿真饰品检测的方法校正和质量控制。     

腐植酸复合肥中的氮、磷、钾含量分析

采用凯氏定氮法、磷钼酸喹啉容量法、ICP-AES法分别分析腐植酸复合肥的氮、磷、钾含量。研究结果表明,在添加不同酸时,应使盐酸的离子浓度大于硫酸的离子浓度,从而消除硫酸盐对磷分析的影响;待测液的酸度控制在1.0~1.6 mol/L为较适宜条件。方法具有良好的准确度和精密度,适用于腐植酸复合肥中氮、磷、钾的精确分析。     

Charged particle activation analysis of phosphorus in biological materials

Charged particle activation analysis of phosphorus in biological materials using the³¹P (α,n)^34mCl reaction has been studied. Since^34mCl is also produced by the³²S (α,pn) and the³⁵Cl (α, α′ n) reactions, the thick-target yield curves on phosphorus, sulfur and chlorine were determined in order to choose the optimum irradiation conditions. As a result, it was found that the activation analysis for phosphorus without interferences from surfur and chlorine is possible by bombarding with less than 17 MeV alphas. The applicability of this method to biological samples was then examined by irradiating several standard reference materals. It was confirmed that phosphorus can readily be determined at the detection limit of 1 μg free from interferences due to the matrix elements.     

Contribution a l’etude du dosage par radioactivation du soufre et du phosphore en tres faibles concentrations dans les metaux de tres haute purete (Aluminium,magnesium, cuivre,fer, nickel)

The analytical procedure for the determination of sulfur in copper by activation with thermal neutrons is given. The purifications necessary to obtain a radiochemically pure precipitate of baryum sulphate are described. The occurrence of some discrepant values in the determinations led to the observation, for the first time, of abnormally high contents of³⁵S^* at a relatively important depth in the samples of irradiated copper (as deep as about 300 μ). Therefore it is necessary to etch the samples to a depth of 300 μ at least on each surface, before doing the chemical separations. Owing to the great influence of the reaction³⁵Cl(n,p)³⁵S^*, the determination of sulfur by thermal neutrons is only possible at contents higher than 10⁻⁶, even if the chlorine concentration is very low (2·10⁻⁸ Cl introduces a correction in terms of sulfur of the order of 10⁻⁶). For sulfur contents lower than 10⁻⁶, the determination is made by irradiation in fast neutrons. The analytical procedure is described and the corrections in the presence of phosphorus and chlorine are discussed. At contents of the order of 10⁻⁸, the corrections are very small and the determination of some 10⁻⁷ of sulfur is easy. Finally, the determination of phosphorus in copper by activation in thermal neutrons is given. The chemical separations are the same as in the preceding case. Contents of the order of 10⁻⁸ phosphorus are determined without difficulty. The results of the determination of sulfur and phosphorus in many samples of copper are indicated: OFHC copper, High Purity copper (99.999%) and different samples of zone refined copper prepared at the Vitry’s Laboratory.      

Ammoxidation of methylpyrazine over phosphorus-modified vanadium-titanium catalysts

Vanadium-titanium catalysts modified with phosphorus additives (1-15 wt.% of P₂O₅) have been studied in methylpyrazine ammoxidation. Introduction of high amounts of the additive (≥ 10 wt.% of P₂O₅) results in a decrease in activity and selectivity of the catalysts due to formation of low active phase - a ternary compound with the component ratio V : P : Ti ≈ 1 : 1 : 1 with only one type of slightly distorted tetrahedral vanadium (5+) bound via oxygen to phosphorus (5+). The nature of the active sites of the samples modified with 1-5 wt.% of P₂O₅, similarly to that in the V-Ti-O catalyst, was found to include the V⁵⁺ cations strongly bound with TiO₂ and located in the significantly distorted octahedral oxygen environment. This revised version was published online in June 2006 with corrections to the Cover Date.     

Fluorine and chlorine doping in oxygen-deficient perovskites: A strategy for improving chemical stability

The present work describes the effect of fluorine and chlorine doping on the chemical stability of proton conductors Ba₂In₂O₅, Ba₄In₂Zr₂O₁₁, and Ba₄Ca₂Nb₂O₁₁ against carbon dioxide and water steam. It was proved that both undoped and halide-doped compositions demonstrate good chemical stability under H₂O treatment without degradation and without any hydrolytic decomposition. The hydration process leads to the change in the crystal structure only. The treatment in the CO₂/air (1:1) atmosphere (500 °C, 10 h) leads to the decomposition of undoped samples only. Halide-doped samples retain their structure without detectable products, that is, they are more chemically stable compared with undoped compositions. The method of halide doping can be used as the promising technique for obtaining the new perovskite-related materials with high level of chemical stability.     

Chemical analysis of sulfur species in geothermal waters

Analytical methods have been developed to determine sulfur species concentrations in natural geothermal waters using Reagent-Free™ Ion Chromatography (RF™-IC), titrations and spectrophotometry. The sulfur species include SO₄²⁻, S₂O₃²⁻, and ∑S²⁻ with additional determination of SO₃²⁻ and S_xO₆²⁻ that remains somewhat semiquantitative. The observed workable limits of detections were ≤0.5 μM depending on sample matrix and the analytical detection limits were 0.1 μM. Due to changes in sulfur species concentrations upon storage, on-site analyses of natural water samples were preferred. Alternatively, the samples may be stabilized on resin for later elution and analysis in the laboratory. The analytical method further allowed simultaneous determination of other anions including F⁻, Cl⁻, dissolved inorganic carbon (DIC) and NO₃⁻ without sample preservation or stabilization. The power of the newly developed methods relies in routine analysis of sulfur speciation of importance in natural waters using techniques and facilities available in most laboratories doing water sample analysis. The new methods were successfully applied for the determination of sulfur species concentrations in samples of natural and synthetic waters.     

Organophosphorus compounds: I. Simple,rapid, and reliable method for the simultaneous microdeterminaton of carbon,hydrogen, and phosphorus by the rapid straight empty tube method

A method for the simultaneous microdetermination of C, H, and P is presented. The organophosphorus compound is pyrolyzed in a 80-mm long silica sample capsule using the rapid straight empty tube method. Carbon and hydrogen are determined by conventional gravimetry. Oxides of phosphorus are quantitatively retained on the walls of the capsule. The P₅O₂, uptake is determined gravimetrically for the phosphorus determination.Organophosphorus compounds containing sulfur can also be analyzed following the same procedure. Electrolytic silver, heated at 550 °C, absorbs the oxides of sulfur. The results obtained fall within the acceptable limits of error.     

Multivariate data analysis of some Finnish water courses

Summary The following parameters were analyzed 2 to 4 times a year from 37 sampling sites; T, O₂, O₂%, Turbidity, Suspended solids, Conductivity, Alkalinity, pH, Color, COD_Mn, Total nitrogen, Total phosphorus, Cl, Fe, Mn, Total sulphur, K, Na, Ca, Mg, SiO₂, Total organic chlorine and Total organic bromine. Samples were taken from waters loaded by chemical pulp mills, other industries, municipal waste waters and agriculture. Also waters under natural conditions were included. Water samples have been collected and analyzed in co-operation with the National Board of Waters and the Environment. The data set was analyzed by Principal Component Analysis (PCA) to determine correlations between variables, especially between Total organic chlorine and Total organic bromine and others. Typically Total organic chlorine and Total organic bromine correlated with Na, Cl and Total sulphur. It is interesting to note that Total organic chlorine and Total organic bromine did not follow each other in all components. Total organic chlorine was predicted using other variables and Partial Least Squares (PLS) method. Very satisfactory correlation was obtained between analyzed and predicted lgTOCl values. Optimally three different object classes were found from the whole data using fuzzy clustering analysis. One class represents waters in a natural condition, one water loaded mainly by agriculture and one represent the rest of the waters.     

Cloud point extraction for the determination of cadmium and lead in biological samples by graphite furnace atomic absorption spectrometry

The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of Cd and Pb from digested biological samples. After complexation with O,O-diethyldithiophosphate (DDTP) in hydrochloric acid medium, the analytes are quantitatively extracted to the phase rich in the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 0.1 mol L⁻¹ HNO₃ was added to the surfactant-rich phase prior to its analysis by electrothermal atomic absorption spectrometry (ET AAS). The adopted concentrations for DDTP, Triton X-114 and hydrochloric acid were all optimized. Pyrolysis and atomization temperatures were optimized using the extracts and pyrolysis temperatures of 700 °C for both elements and atomization temperatures of 1400 and 1600 °C for cadmium and lead, respectively, were used without adding any modifier, which shows that considerable analyte stabilization is provided by the medium itself. A more detailed investigation was carried out to determine which components of the extract were responsible for the high thermal stability achieved and it revealed that the amount of DDTP added and the phosphorus content of the digested samples contributed significantly to this phenomenon. Detection limits (3σ_B) of 6 and 40 ng g⁻¹, along with enrichment factors of 129 and 18 for Cd and Pb, respectively, were achieved. The proposed procedure was applied to the analysis of five certified biological reference materials after microwave-assisted acid digestion in a mixture of H₂O₂ and HNO₃. Comparison with certified values was performed for accuracy evaluation, resulting in good agreement according to the t-test for a 95% confidence level. The high efficiency of cloud point extraction to carry out the determination of the studied analytes in complex matrices was, therefore, demonstrated.     

Beiträge zur Chemie von Phosphorverbindungen mit Adamantanstruktur. XI. Über Darstellung und Eigenschaften von Phosphoroxidsulfiden der allgemeinen Formel P4O10−nSn (n = 2−9)

Contributions to the Chemistry of Phosphorus Compounds with Adamantane-like Structure. XI. Preparation and Properties of Phosphorus Oxide Sulfides of the General Formula P₄S_10?n S_n (n = 2?9) The reaction of P₄O₁₀ with P₄S₁₀ yields a mixture of phosphorus oxide sulfides of the general formula P₄O_10?nS_n. Depending on the molar ratio P₄O₁₀: P₄S₁₀ in the starting product different amounts of the individual phosphorus oxide sulfides occuring in this reorganization product are formed. Besides the well-known P₄O₆S₄ the compounds P₄O₇S₃, P₄O₅S₅, P₄O₄S₆, P₄O₃S₇, P₄O₂S₈, and P₄OS₉ occuring for the first time were obtained by fractional distillation or crystallization. The compound P₄O₈S₂ was identified by N.M.R. spectroscopy.     

高频红外碳硫分析仪测定石膏矿中的三氧化硫

利用高频红外碳硫仪对石膏矿中三氧化硫含量的测定进行了研究,取得了较好的结果.方法检出限为0.003 0%.用石膏标准样品(GBW03109a,GBW03110)进行分析,测定值与认定值相符,测定值的相对标准偏差(n=9)在0.32%~0.81%之间.使用石膏标准样品(GBW03111)进行本法与国标硫酸钡重量法做比对试验,测定结果无显著性差异.加标回收率为96.4%~104.0%.