硝酸稀土与蛋氨酸配合物的合成及表征

在相平衡研究的基础上合成了１２种硝酸稀土与蛋氨酸的配合物。通式为ＲＥ（Ｍｅｔ）４（ＮＯ３）３·６Ｈ２Ｏ（ＲＥ＝Ｌａ～Ｎｄ，Ｓｍ～Ｄｙ，Ｅｒ，Ｙｂ，Ｙ）的配合物用化学分析、ＩＲ、电子光谱、ＦＳ、Ｘ射线衍射、ＴＧ－ＤＴＧ和ＤＳＣ进行了表征。在ＩＲ光谱中观察到的“四分组效应”规律表明：稀土阳离子与蛋氨酸间存在一定程度的共价。     

REPS4(RE=Y, La～Lu)系列化合物的合成和结构化学研究

采用高温固相反应合成了稀土硫代磷酸盐ＲＥＰＳ４（ＲＥ＝Ｙ，Ｌａ～Ｌｕ），并通过Ｘ射线粉末衍射测定了晶胞参数以及ＨｏＰＳ４，ＥｒＰＳ４和ＴｍＰＳ４的晶体结构。其中ＲＥＰＳ４（ＲＥ＝Ｙ，Ｌａ～Ｙｂ）系列化合物的结构均属四方晶系，其空间群为Ｉ４１／ａｃｄ，ａ≈１１ｎｍ，ｃ≈１９ｎｍ，Ｚ＝１６。四方结构中的三价稀土离子为反四方棱柱八配位。该结构具有较大的孔洞空间，孔洞直径分别为０６２５ｎｍ（沿ｃ轴方向）和０３５ｎｍ（沿ａ、ｂ轴方向）。ＬｕＰＳ４晶体为单斜晶系，很可能是层状（２Ｄ）结构。研究了镧系收缩效应对四方结构稳定性的影响，发现对ＲＥＡＸ４系列化合物来说，四方结构能稳定存在的前提是２４ｄＡＸ／ｒ１９。     

La(ClO4)3-OCBAAP-H2O体系(30℃)溶度及Ln(OCBAAP)4(ClO4)3·nH2O的合成和表征

测定了三元体系Ｌａ（ＣｌＯ４）３－ＯＣＢＡＡＰ－Ｈ２Ｏ在３０℃时的溶解度．结果表明，该体系有一个新固相（不一致溶解化合物）Ｌａ（ＯＣＢＡＡＰ）４（ＣｌＯ４）３·６Ｈ２Ｏ形成．参考该体系溶度图确定合成条件，合成了系列化合物Ｌｎ（ＯＣＢＡＡＰ）４（ＣｌＯ４）３·ｎＨ２Ｏ（Ｌｎ＝Ｌａ，ｎ＝６；Ｌｎ＝Ｐｒ，Ｎｄ，Ｓｍ，Ｇｄ，Ｙｂ，ｎ＝２）．通过化学分析、元素分析、ＴＧ－ＤＴＧ、ＩＲ和密度对化合物进行了表征，计算了Ｌａ（ＯＣＢＡＡＰ）４（ＣｌＯ４）３热分解过程各阶段的表观活化能．     

稀土与H2salen配合物的合成与波谱性质

合成了稀土Ｎ，Ｎ－亚乙基双（水杨醛缩亚胺）（Ｈ２ｓａｌｅｎ）双核配合物，通过元素分析、热分析、紫外、红外、远红外光谱、磁化率及１Ｈ、１３ＣＮＭＲ谱与Ｔ１的测定，确定了他们与前人合成的配合物有所不同，其化学组成为［Ｌｎ２（Ｈ２ｓａｌｅｎ）３（ＮＯ３）４］（ＮＯ３）２·３Ｈ２Ｏ（Ｌｎ＝Ｌａ，Ｐｒ，Ｎｄ，Ｓｍ，Ｇｄ，Ｔｂ，Ｅｒ，Ｙｂ及Ｙ），并对它们的配位作用、波谱及可能应用进行了探讨．     

稀土与α—萘乙酸配合物的合成和性质研究

本文合成了１１种稀土与α－萘乙酸的配合物。元素分析结果表明配合物的组成为ＲＥ（Ｃ１２Ｈ９Ｏ２）３．２Ｈ２Ｏ（ＲＥ＝Ｌａ，Ｃｅ，Ｐｒ，Ｎｄ，Ｓｍ，Ｅｕ，Ｇｄ，Ｄｙ，Ｅｒ，Ｙｂ，Ｙ），并通过配合物的ＩＲ，ＵＶ，Ｈ－ＮＭＲ，ＴＧ－ＤＴＡ，ＸＰＳ，磁化率，摩尔电导及溶解性的研究。     

Keggin结构稀土钼钒磷四元杂多配合物的合成,表征及苯酚？…

合成了５种通式为（ＮＨ４）１５「ＲＥ（ＰＭｌ９Ｖ２Ｏ３９）２」．ｘＨ２Ｏ（ＲＥ＝Ｌａ＾３＋,Ｃｅ＾３＋,Ｇｄ＾３＋,Ｙ＾３＋,Ｙｂ＾３＋）的稀土钼钒磷四元杂多配合物,并用ＩＲ,ＵＶ,ＸＲＤ,ＩＣＰ,ＴＧ－ＤＴＡ和ＣＶ等手段对其结构和性能进行了表征。催化活性实验表明,标题化合物对苯酚过化羟化制苯二酚反应有良好的催化活性。     

NTO稀土盐的合成,结构表征和热分解机理

用３－硝基－１，２，４－三唑－５－酮（ＮＴＯ）的锂盐与稀土的硝酸盐在水溶液中反应，制备了１１种稀土的ＮＴＯ盐，用现代仪器分析方法确证了它们的组成式为ＲＥ（ＮＴＯ）＿３·ｎＨ＿２Ｏ，当ＲＥ为Ｙ、ｌａ、ｃｅ、Ｐｒ、Ｎｄ、Ｓｍ、Ｅｕ、Ｇｄ、Ｔｂ、Ｄｙ和Ｙｂ时，ｎ分别为６、７、７、７、８、７、７、７、５、５和６，并用ＤＳＣ、ＴＧ－ＤＴＧ和ＦＴ－ＩＲ技术研究了这些盐在等速升温条件下的热分解机理。     

Ln（ClO_4）_3－DAPTU－H_2O三元体系30℃时的相平衡研究

测定了Ｌｎ（ＣｌＯ_４）_３－ＤＡＰＴＵ－Ｈ_２Ｏ（Ｌｎ＝Ｌａ，Ｓｍ，Ｙｂ）三元体系在３０℃时的溶解度及饱和溶液的折光率，绘制了相应的溶度图和折光率－组成图，各体系的溶度曲线和折光率曲线均由三支组成，分别与ＤＡＰＴＵ、Ｌｎ（ＤＡＰＴＵ）_２（ＣｌＯ_４）_３·８Ｈ_２Ｏ（Ｌｎ＝Ｌａ，Ｓｍ，Ｙｂ）和Ｌｎ（ＣｌＯ_４）_３·ｎＨ_２Ｏ（Ｌｎ＝Ｌａ，ｎ＝８；Ｓｍ，ｎ＝９；Ｙｂ，ｎ＝８）相对应。从溶度图上发现了３个未见文献报道的固液异组成溶解的化合物，通过化学分析及元素分析、ＴＧ－ＤＴＧ、ＩＲ对其进行了表征。     

Cu（Ⅱ）－Ln（Ⅲ）双核配合物的合成、磁性和抗菌活性

合成和表征了６种以草酰胺为桥联的异双核配合物Ｃｕ（ｏｘｅｎ）Ｌｎ（ｐｈｅｎ）２（ＣｌＯ４）３（ｏｘｅｎ代表Ｎ，Ｎ′－双（２－氨乙基）草酰胺根阴离子；ｐｈｅｎ为１，１０－邻菲咯琳；Ｌｎ表示Ｙ、Ｌａ、Ｃｅ、Ｎｄ、Ｇｄ和Ｙｂ）．测定了Ｃｕ（ｏｘｅｎ）Ｇｄ（ｐｈｅｎ）２（ＣｌＯ４）３·Ｈ２Ｏ的变温磁化率（４～３００Ｋ）；井用最小二乘法和从自旋Ｈａｍｉｌｔｏｎｉａｎ算符导出的磁方程拟合，求得交换积分Ｊ＝２．３ｃｍ－１；表明配合物中Ｃｕ（Ⅱ）和Ｇｄ（Ⅲ）离子间存在弱的铁磁性超交换作用。测试了配合物的抗菌活性。     

镧系离子与5,7-二氯-8-羟基喹啉-藏红花三元离子缔合物的萃取-光度分析特性

以Ｓｍ３＋为例研究了Ｌｎ３＋５，７二氯８羟基喹啉（ＤＣＯ）藏红花（ＳＦＴ）形成三元离子缔合物的萃取光度特征。用平衡移动法测定了离子缔合物的摩尔比Ｌｎ３＋∶ＤＣＯ∶ＳＦＴ＝１∶４∶１。在ｐＨ６８０～７５０的范围内，萃取物的λｍａｘ＝５２４ｎｍ，εｍａｘ＝４７０×１０４Ｌ·ｍｏｌ－１·ｃｍ－１。Ｓｍ３＋在０２～１５μｇ·ｍｌ－１范围内符合比尔定律。研究表明镧系离子的相对吸光度（ＡＬｎ／ＡＬａ）随原子序数呈现奇偶变化规律。     

On-line fermentation gas analysis: Error analysis and application of mass spectrometry

On-line fermentation gas analysis is of general interest because it permits the determination of metabolic rates in almost any biological process using living organisms. The consumption and production of gases (O₂, CO₂, CH₄, etc.) and volatile compounds may be determined without causing any risk of infection. Elemental balancing permits the determination of other metabolic rates if the stoichiometry is known. This was studied with the production of poly-β-hydroxybutyrate (PHB) by Alcaligenes latus. Estimations were based on the measurement of gas partial pressure and flow-rates, pH and alkali consumption rate. Experiments with a small quadrupole mass spectrometer showed unacceptable error propagation. Therefore, dynamic error propagation for all rates was studied using simulation. It was found that, for example, a 1% relative offset-calibration error for oxygen can result in an error in PHB estimation of > 50%. It is suggested that this culture is used in combination with elemental balancing for thorough tests of the accuracy of on-line gas analysis equipment. An on-line process gas analyser based on a quadrupole mass spectrometer (Balzers PGM 407) gave the following precision values (abs. vol.?%) during cultivation of Bacillus subtilis: nitrogen (m/z 14), 0.024; oxygen (m/z 32), 0.020; argon (m/z 40), 0.0011; and carbon dioxide (m/z 44), 0.0034. These values, combined with automatic recalibration, would be sufficient for reasonable estimation of PHB, biomass and substrates.     

Impact of alkali treatment on physico-chemical,thermal, structural and tensile properties of Carica papaya bark fibers

This study aims to examine the effect of sodium hydroxide (NaOH) treatment on the physico-chemical properties, structure, thermal, tensile and surface topography of Carica papaya fibers (CPFs). The surface of raw CPFs was modified by soaking with 5% NaOH solution for 15, 30, 45, 60, 75 and 90?min. The results of thermo-gravimetric analysis revealed that the optimum treatment time for alkali treatment was 60?min. It was found that the alkali treatment improved the properties of the CPFs. The results of TGA, FT-IR, XRD and AFM suggest that the treated CPF is a suitable alternative as reinforcement in polymer composites.     

Chemometric and trend analysis of water quality of the South Chennai lakes: an integrated environmental study

In order to bring out the nature of the factors influencing lake water composition, multivariate statistical analysis and trend analysis were performed based on the hydrochemical data of the study area, namely, South Chennai. Change in land use pattern and settlements along the banks of the lakes alters the quality and quantity of the surface water. In the present study, the R‐mode factor analysis and cluster analysis were applied to the geochemical parameters of the water to identify the factors affecting the chemical composition of the lake water. Dendograms of both the seasons give three major clusters, reflecting the groups of unpolluted to moderately polluted, polluted, and heavily polluted stations. The movement of stations from one cluster to another clearly brings out the seasonal variation in the chemical composition of the lake water. The complex hydrochemical data of the surface water were interpreted by condensing them into three major factors. Factor score analysis was used successfully to delineate the stations under study and the role of the contributing factors, and the nature of factors responsible for the variation in chemical composition of the water has been clearly brought out. Results of trend analysis using ArcGIS clearly indicate that the trend in water quality is deteriorating at a faster rate in the eastern part of the study area. It is understood that although natural shifts probably can account for some of the variation, it is most likely that human activities play a major role in affecting the water quality on a regional scale. Copyright © 2014 John Wiley & Sons, Ltd.     

Time-series analysis in analytical process control

Analysis of time series tries to extract tendencies from measured values dependent on time. For this purpose the cusum technique has proved to be a very sensitive tool for the evaluation of both current and completed time series. Even very weak tendencies can be detected at a high level of noise. Time-series analysis further tries to predict values to come from hitherto performed measurements. As a very flexible model exponential smoothing could be successfully used. Even for processes with a high extent of non-stationarity this model allowed a good prediction owing to the dynamics of the process. Three types of time-series analysis, i.e., evaluation of current measurements, retrospective evaluation and prediction of data (also known as “in vivo”, “post mortem” and “in futurum” time-series analysis) are demonstrated for problems stemming from analytical process control.     

新材料的发展与分析化学

文章介绍了新材料的重要性及发展方向,分析化学在新材料研制中起着耳目的作用,另一方面新材料也为分析化学的进展提供了课题与条件。微量分析、微区分析、表面分析是此领域中的重点。在未来的发展中,分析化学在材料的发展中的地位不会改变,并期待着分析灵敏度与空间分辩率的进一步提高。     

Determination of rank by augmentation (DRAUG)

Determining the rank of a chemical matrix is the first step in many multivariate, chemometric studies. Rank is defined as the minimum number of linearly independent factors after deletion of factors that contribute to random, nonlinear, uncorrelated errors. Adding a matrix of rank 1 to a data matrix not only increases the rank by one unit but also perturbs the primary factor axes, having little effect on the secondary axes associated with the random errors in the measurements. The primary rank of a data matrix can be determined by comparing the residual variances obtained from principal component analysis (PCA) of the original data matrix to those obtained from an augmented matrix. The ratio of the residual variances between adjacent factor levels represents a Fisher ratio that can be used to distinguish the primary factors (chemical as well as instrumental factors) from the secondary factors (experimental errors). The results gleaned from model studies as well as those from experimental studies are used to illustrate the efficacy of the proposed methodology. The method is independent of the nature of the error distribution. Limitations and precautions are discussed. An algorithm, written in MATLAB format, is included. Copyright © 2011 John Wiley & Sons, Ltd.     

Determination of Mercury in Geological Materials by Continuous-Flow,Cold-Vapor,Atomic Absorption Spectrophotometry

Abstract

To determine mercury in geological materials, samples are digested with nitric acid and sodium dichromate in a closed teflon vessel. After bringing to a constant weight, the digest is mixed with air and a sodium chloride-hydroxylamine hydrochloride-sulfuric acid solution and then Hg(II) is reduced to Hg with stannous chloride in a continuous flow manifold. The mercury vapor is then separated and measured using cold vapor atomic absorption spectrophotometry (CV-AAS). For a 100 mg sample the limit of detection is 20 parts per billion (ppb) Hg in sample. To obtain a 1% absorption signal, the described method requires 0.21 ppb Hg solution (equal to 16 ppb in sample). Precision is acceptable at less than 1.2% RSD for a 10 ppb Hg aqueous standard. Accuracy is demonstrated by the results of the analysis of standard reference materials. Several elements do interfere but the effect is minimal because either the digestion procedure does not dissolve them (e.g., Au or Pt) or the; are normally of low abundance (e.g., Se or Te).     

钴-5-Br-PADAP极谱催化波研究

许多作者研究了某些有机试剂存在时钴的极谱行为.本文报道在氢氧化钠和盐酸羟胺底液中,钴-5-Br-PADAP配合物的极谱行为,证明峰电流为配合物吸附波.将铁分离后测定标钢中微量钴,与光度法结果一致,直接测定茶叶中钴,结果满意.