Behaviour Of Several Elements Research Articles

New insights on Late Pliensbachian-Early Toarcian seawater chemistry based on belemnite rostra element content

Belemnites were a type of cephalopod abundant in the Jurassic and Cretaceous, whose fossils have been extensively used for paleo-oceanographic studies. For this study, we analyzed 69 elements by Inductively Coupled Plasma-Sector Field Mass Spectrometry (ICP-SFMS) in 15 belemnite rostra from the West Rodiles section in the Asturian Basin, Northern Spain. We aim to determine if belemnite rostra carbonate chemistry reflects changes in seawater chemistry during the Late Pliensbachian–Early Toarcian time interval and examine how belemnites can be used to trace known drivers of the Early Toarcian Oceanic Anoxic Event (T-OAE) and associated oceanographic processes.Discarding drastic intra-species effects and assuming a similar influence of growth rates, diet, and other physiological processes for all analyzed belemnite specimens and taking into consideration the sizeable analytical uncertainty, we assess if determined belemnite rostra element chemistry reflects broad and relative changes in paleo-seawater chemistry. Many determined elements are present in only ppb amounts, and their interpretation is uncertain. We found that Mg, Mn, and P increase in the interval chronocorrelative to the T-OAE. This is interpreted to have resulted from an increase in these elements' inventory in seawater due to an increase in continental weathering and fluvial runoff associated with this global event. Iron, K, and Na contents decrease upwards in the section, potentially indicating that these elements became limited and likely hampered oceanic productivity. Our study also found a correspondence between a change in the behaviour of several elements, warming, the T-OAE negative CIE, and a reduction in the diversity and size of both calcareous nannofossils and belemnites in the study area.

Lithium and sodium in the globular cluster M 4

Context. The abundance inhomogeneities of light elements observed in globular clusters (GCs), and notably the ubiquitous Na-O anti-correlation, are generally interpreted as evidence that GCs comprise several generations of stars. There is an on-going debate as to the nature of the stars, which produce the inhomogeneous elements, and investigating the behavior of several elements is a way to shed new light on this problem.

Temperature Effects on the Concentration of Cl and Br and Seasonal Behavior of Several Elements in Urban Air in the South of Saitama, Japan

Temperature Effects on the Concentration of Cl and Br and Seasonal Behavior of Several Elements in Urban Air in the South of Saitama, Japan

Performance evaluation of collision–reaction interface and internal standardization in quadrupole ICP-MS measurements

The combined use of internal standardization with collision and reaction interface in an inductively coupled plasma quadrupole mass spectrometer (ICP-QMS-CRI) was evaluated. The behavior of several elements (Ba, Cd, Co, Cr, Cu, Li, Mn, Mo, Pb, Sb, V and Zn) was studied by introducing H2 or He through the skimmer and sampler cones of the CRI device and by using In, Rh and Sc as internal standards. Certified reference material of trace elements in water (NIST 1643e) was used to evaluate the performance of the method. A vinegar sample and mixed food diet standard reference material were directly introduced into the equipment as complex matrices for Cr and V determinations. Improvements in accuracy and precision were attained combining both strategies. The introduction of H2 through the skimmer cone was the best way to overcome polyatomic ions formation and to improve SBR and BEC values for several elements. The use of Sc as internal standard improved the performance of ICP-QMS-CRI.

Cation- exchange behaviour of several elements in nitric acid- organic solvent media

يهدف هذا البحث الى دراسة معامل توزيع عدد من عناصر كايونات الفلزات نيكل، باريوم، المنيوم، كروم، نحاس، الخ، على المبادل الكااتيوني ستنانيك سليكومولبيدات في الشكل الهيدرجوني في انظمة مائية ومائية عضوية ذات ثوابت عزل مختلفة كالايثانول، الايثلين جليكون والجليسرول. اتبع البحث المنهج التجريبي، وقسم الى مقدمة ومبحثين وخاتمة، تناول المبحث الاول توضيح تاثير النسبة المؤوية للمذيب العضوي وكذلك درجة حرارة معامل التوزيع، وتناول الثاني تحديد كفاءة هذا المبادل وسبب الفروق لقيم معامل التوزيع. أما الخاتمة فضمنت اهم النتائج ومنها: معرفة كفاءة المبادل الكاتيوني، ومعرفة درجة الحرارة المثلى للحصول على اعلى قيم لمعامل التوزيع هي 50 درجة مئوية.

EFFECTS OF PACLOBUTRAZOL AND CROP-LOAD ON MINERAL ELEMENT CONCENTRATION IN DIFFERENT ORGANS OF “CATHERINE” PEACH TREES

ABSTRACT The concentration of mineral elements in leaves and shoots of “Catherine” peach [Prunus persica (L.) Batsch.] trees with different crop-loads and treated with or without 2 g paclobutrazol (PP333) was analyzed. For most elements, the concentrations in the leaf varied linearly along the growing season, the concentrations of nitrogen (N), potassium (K), copper (Cu), and zinc (Zn) decreasing, those of calcium (Ca), magnesium (Mg), and manganese (Mn) increasing, while the concentration of iron (Fe) did not follow a clear pattern. PP333 increased concentration of calcium (Ca), Mg, Fe and Mn, and a decrease in K, while the pattern of change of concentration of N varied so that more N was exported from leaves of PP333 treated trees than from untreated trees. Crop-load also affected leaf N, Mg, and Mn concentration, but no effects were observed on K, Ca, and Fe concentration. In terminal shoots, PP333 increased the concentrations of all elements except K and Mg, and the level of cropping induced changes in the behavior of several elements: K, Mg, Fe, Mn, and Cu concentrations increased with crop-load in control trees, while in PP333-treated trees, they either decreased (Fe, Mn, and Cu) or remain unchanged (K and Mg), and phosphorus (P) concentration decreased both in PP333-treated or untreated trees. It is concluded that mineral element distribution among leaves and shoots is affected by PP333 and by the level of cropping.

An experimental study of the behaviour of several elements in inductively coupled plasma mass spectrometry using the single-bore high-pressure pneumatic nebulizer

The behaviour of several elements using a new single-bore high-pressure pneumatic nebulizer (S) and a Meinhard nebulizer (M) in ICP-MS (VG PlasmaQuad PQ2 instrument) has been studied using the liquid flow, the gas flow and the relative distance (axial and transverse) from sampler to coil as variables for comparison. Drop size distributions of primary aerosols and transport rates have also been measured with both nebulizers. The results show that: (1) under the same conditions, nebulizer S provides finer primary aerosols and higher transport rates than M; (2) for any given set of experimental conditions, the signal ratios I S I M are different for each element, show smooth variations with the atomic mass of the element and do not seem to be related to the transport ratio (m A ) S (m A ) M , where m A is the amount of analyte transported to the plasma; (3) for many elements, an increase in the liquid flow causes a marked increase in the signal with either nebulizer, in spite of the fact that m A has decreased and the water load has increased; (4) the gas and liquid flows that maximize the signal are always lower for S than for M, and the optimized signals are 1.5 to 3 times higher for the former; (5) for both nebulizers, the variation tendencies of the signal for each element when the gas flow, the liquid flow or the sampler position is varied seem to be closely related to the atomic mass of the element. These results have been explained in terms of the “zone model” recently proposed by Vanhaecke et al. (J. Anal. At. Spectrom., 8 (1993) 433), which is based on the different rates of radial diffusion achieved by the ions from the central channel of the plasma according to their mass.

窒素中での銀／ニッケルめっき間の銅ストライクめっきの熱拡散挙動

Copper substrate with a double-layer silver/nickel film having copper strike plating between the layers was analyzed by Auger electron spectroscopy after thermal treatment in a nitrogen atmosphere, and the thermal diffusion behavior of several elements, including oxygen, was measured. These profiles were compared with those obtained after thermal treatment in air.The results can be summarized as follows(1) The thermal diffusion of the copper in the copper strike plating was considerably influenced by the oxygen concentration during thermal treatment.(2) Some of the copper of the intermediate layer diffused onto the silver surface after thermal treatment in nitrogen. Diffused copper formed an oxide film with a slight amount of oxygen, and the surface discolored.(3) Since inner oxidation of the plating layers did not occur with thermal treatment in nitrogen, the adhesion of the plating was good.

Anion-exchange behaviour of several elements in systems containing formic acid

The anion-exchange characteristics of 27 elements toward the strongly basic anion-exchange resin Amberlite CG-400 in media containing aqueous formic acid and mixtures of formic acid with sodium formate, hydrochloric acid, sodium nitrite, acetone and methanol have been investigated. Possible separations are described and discussed. The quantitative separations achieved are Sr-La, Zn-Cd-Hg, and Ni-Fe.

Cation-exchange behaviour of several elements in formic acid solution

The cation-exchange characteristics of 20 elements towards the strongly acidic cation-exchange resin Dowex 50 × 8 in media containing varying concentrations of formic acid and mixtures of formic acid with aqueous dioxan were investigated. Possible separations are indicated and discussed. Bismuth may be quantitatively separated from copper.

Anion-exchange behaviour of several elements in hydrobromic acid-organic solvent media

The anion-exchange behaviour of 19 elements in hydrobromic acid-organic solvent media has been investigated. The batch distribution coefficients of the metal ions were determined in these systems employing the strongly basic anion-exchange resin Dowex 1, × 8. Organic solvents used were methanol, ethanol, n-propanol, isopropanol, methyl glycol, acetone, tetrahydrofuran and acetic acid. The most suitable conditions for some quantitative separations based on these equilibrium studies are indicated and discussed.

Reconsideration of the Criteria to Determine Practical Fluctuational Concentration Limits in Atomic-Absorption Flame Photometry

A study is presented on the influence of the instrumental time constant value in the determination of fluctuational sensitivity in atomic-absorption flame photometry. Fluctuational concentration limit (detection limit) has been defined as a function of the noise level of the blank reading (blank adjusted at the 0% absorption level), while the signal noise is a direct function of the time constant of the readout system employed. Employing a Beckman 979 atomic-absorption system and recorder, a scale expander unit was modified to provide a time constant control. The behavior of several elements is presented as an example of the dependence of the fluctuational concentration limit on the system time constant. These results, clearly indicating a basic relationship, lead to the establishment and presentation of a new criterion in an attempt to define and to compare concentration limits of a fluctuational nature.

Cation-exchange behaviour of several elements in hydrobromic acid-organic solvent media

The cation-exchange characteristics of 19 elements in hydrobromic acid-organic solvent media have been investigated. In these systems the batch distribution coefficients of the metal ions were determined, using the strongly acidic cation-exchange resin Dowex 50, X8. Methanol, ethanol, n-propanol, isopropanol, methyl glycol, acetone, tetrahydrofuran and acetic acid have been used as the organic solvents. The conditions most suitable for the quantitative separation of the elements are indicated and discussed. Several examples of successful separations are tabulated.

Cation-exchange behaviour of several elements in hydrofluoric acid-organic solvent media

The cation-exchange characteristics of 15 elements with the strongly acidic cation-exchange resin Dowex 50 × 8 were investigated in media containing varying concentrations of organic solvents and aqueous hydrofluoric acid. The determination of the distribution coefficients was carried out in 0.15–1.2 M hydrofluoric acid solutions containing 0–90% of the organic solvents methanol, ethanol, n-propanol, isopropanol, methyl glycol, acetone, tetrahydrofuran, and acetic acid. Based on these distribution data the possibilities of separations of the various elements are indicated and discussed.

IOn-exchange behaviour of several elements in mixed solvents

The distribution coefficients between the cation- and anion-exchangers Dowex 50 and Dowex 1, and aqueous solutions containing nitric or hydrochloric acid and organic solvents with or without amines or complexing agents, have been obtained for a number of metals including uranium, thorium, cerium, iron, copper, and nickel. The organic solvents were methanol, acetone and dimethylformamide; the amines were tributylamine and tribenzylamine, and the complexing agents EDTA and citric acid. Both batch and column methods were used.

Cation-exchange behaviour of several elements in nitric acid-organic solvent media

The cation-exchange behaviour of 19 elements towards the strongly acidic cation-exchange resin Dowex 50-X8 in media containing varying concentrations of organic solvents and aqueous nitric acid is reported. Based on the determination of the distribution coefficients of these elements in the organic solvents methanol, ethanol, n-propanol, isopropanol, methyl glycol, acetone, tetrahydrofuran and acetic acid, the conditions most suitable for their quantitative separation are indicated and discussed.

Cation-exchange behaviour of several elements in hydrochloric acid—organic solvent media

In the present paper the cation-exchange characteristics of 20 elements towards the strongly acidic cation-exchange resin Dowex 50X8 in media containing varying concentrations of organic solvents and aqueous hydrochloric acid were investigated. Based on the determination of the distribution coefficients of these elements in the organic solvents methanol, ethanol, n-propanol, isopropanol, methyl glycol, acetone, tetrahydrofuran, and acetic acid, the conditions most suitable for their quantitative separation are indicated and discussed.

融解ビスマス-融解塩系における諸元素の挙動, (III)

融解ビスマス-融解塩系における諸元素の挙動, (III)

融解ビスマス-融解塩系における諸元素の挙動, (II)

融解ビスマス-融解塩系における諸元素の挙動, (II)

Analytical applications of the Barker square-wave polarograph. Part III. Orthophosphoric acid as a solvent and base electrolyte in direct inorganic polarographic analysis

Orthophosphoric acid is a versatile solvent for diverse materials and the resulting solutions may be analyzed polarographically. The polarographic behavior of several elements in a M phosphoric acid base solution has therefore been investigated, and half-wave potentials and diffusion-current constants are reported. With use of the square-wave polarograph, simple and direct procedures are described for thc determination of small amounts of lead in copper, tin, zinc and aluminum-base alloys, respectively. The determination of lead (a few tenths of a per cent) in monazite and in various miscellaneous materials is also described. With no samples were chemical separations necessary after their dissolution in phosphoric acid. Direct procedures are also described for the determination of the copper content of lead, tin, and aluminum-base alloys, the zinc content of copper, tin, and aluminum-base alloys, and the cadmium content of tin and lead-base alloys. All the procedures outlined provide a considerable improvement on those in which use is made of conventional polarography. (auth) with a mean recovery of 100.3% and a standard devia