Jakab Loch

A study of plant sample preparation and inductively coupled plasma emission spectrometry parameters

Abstract Adjustable parameters of an inductively coupled plasma emission spectrometer (ICP) are investigated and a digestion method of plant samples is developed which does not require the use of HC104. This HNO3‐H2O2 wet digestion method eliminates the hazards associated with hot, concentrated HClO4. The adjustable parameters of ICP are viewing height, forward power as well as the sample, coolant, auxiliary, and flushing gas flow rates, and the sample uptake flow rate. The digestion parameters examined are the type and amount of the applied acids (HNO3, HCl, and H2SO4), the temperature and duration of predigestion, the amount of H2O2, and the temperature and duration of digestion. Three plant samples (maize seed, wheat straw, and sunflower seed) and three dry weights are analyzed. The optimal parameters of the ICP spectrometer and HNO3‐H2O2 wet digestion for plants are determined. Optimal parameters of HNO3‐H2O2 wet digestion sample preparation: Optimal parameters of the ICP instrument:

Experiences with 0.01M calcium chloride as an extraction reagent for use as a soil testing procedure in hungary

Abstract Soil analytical results arc presented based on long‐term field experiments conducted by the Hungarian Academy of Sciences, Research Institute of Soil Science and Agrochemistry. Owing to the long‐term fertilizer and/or manure applications, there are significant differences in the amounts of soluble organic nitrogen (N) fractions and also in the 0.01 M calcium chloride (CaCl2)‐soluble phosphorus (P) and potassium (K) contents. The P and K balances in the different treatments and the 0.01M CaCl2‐soluble P and K content of the soil highly correlate.

Studies on parameters of inductively coupled plasma spectrometer

Abstract Analytical aspects of different adjustment of parameters of an inductively coupled plasma atomic emission spectrometer (ICP‐AES) were investigated. The ICP‐AES was a LABTAM 8440M (now called GBC) spectrometer. Since at many times, the elemental concentration of the analyte is near to the detection limit, the lowest possible detection limit has to be reached. When the signal‐to‐background ratio (SBR) is maximized, the detection limit is the smallest. This is the reason why the effects of each adjustable parameters on the signal‐to‐background ratios were investigated. Seven adjustable parameters can be analyzed in this equipment: (i) viewing height, (ii) forward power, (iii) sample gas, (iv) coolant gas, (v) auxiliary gas, (vi) flushing gas, and (vii) sample uptake flow rates. Furthermore aerosol distribution by droplet size and nebulization efficiency were also examined applying three different sample gas flow rates and four elements [iron (Fe), magnesium (Mg), manganese (Mn), and nickel (Ni)]. Th...

A simple and inexpensive method for chromium speciation in soil extracts

Abstract Chromium (Cr) appears in two stable forms in nature as Cr(III) and Cr(VI). Hexavalent chromium (CrO4 2‐; Cr2O7 2‐) is very toxic and carcinogenic, while inorganic Cr(III), however, is essential for mammals. Only two methods, atomic absorption and inductively coupled plasma atomic emission (ICP) spectrometry, provide information on the total amount of Cr in a test solution. This is the reason that several efforts have been made with regard to Cr speciation. Either an acidic or a basic activated aluminum oxide and a reversed phase C‐18 column or an ion exchanger column are used for the separation of chromium(III) from chromium(VI) in FIA and HPLC analyses. In our experiments, acidic‐activated aluminum oxide was used for separation. This alumina was placed into a silicon tube and connected to an ICP spectrometer between the nebulizer and peristaltic pump. The average grain size of the alumina was large enough that the solution could be pumped through the micro column. Acidic‐activated aluminum oxide...

Hundredth molar calcium chloride extraction procedure. part III: Calibration with conventional soil testing methods for magnesium

Abstract The results of a joint project of institutes in the Czech Republic, Hungary, Poland, and the Netherlands on calibration of the 0.01M calcium chloride (CaCl2) soil testing procedure for magnesium (Mg) are presented. In soil samples collected in the participating countries, the analytical procedure for soil research according conventional extraction procedures are compared with data achieved with the 0.01M CaCl2 procedure. Linear and quadratic regression analysis were applied to quantify the relations of Mg in the 0.01M CaCl2 extract with the different conventional extractants. With the relatively weak extractant, 0.01M CaCl2 somewhat lower quantities of Mg are extracted from the soil samples compared to the extraction solutions used in Poland (0.0125M CaCl2), in Hungary [1M potassium chloride (KCl)], and in the Netherlands [0.5M sodium chloride (NaCl)]. With the relatively strong extractant used in the Czech Republic (Mehlich II), more Mg is extracted. The relations of conventional extraction proc...

Soil phosphate adsorption and desorption in 0.01m calcium chloride electrolyte

Abstract Using the soil samples of long‐term fertilization experiments started 25 years ago, the factors that determine the phosphorus (P) supply in plants were examined: actual, readily available P content of the soil, soil solution P supply, and P‐adsorption and ‐desorption by the soil. The experiments suggest that the P‐binding (adsorption) is fairly different in soils with different soil properties which fact has to be considered when a growing site specific fertilization is applied. The experiments introduced show that the P‐adsorption can well be monitored with the Fox‐Kamprath method under constant ionic strength (0.01M CaCl2). In the investigated concentration range both the Van Huay equation and the Freundlich isotherm are suited to the description of the experimentally determined P‐adsorption. The adsorptive isotherms of the soil are characteristic of the adsorption determined by soil qualities and make the assessment of fertilizer doses needed to ensure the critical concentration of equilibrium...

Effect of Application of Nitrogen and Different Nitrogen–Sulfur Ratios on the Quality and Quantity of Mustard Seed

A greenhouse experiment was conducted on a calcareous chernozem soil to investigate the effects of nitrogen (N) and sulfur (S) fertilization and their ratios on the yield and quality of white mustard (Sinapis alba L.). Four levels of N [0.5, 1, 1.5, and 2 g pot−1 N as ammonium nitrate (NH4NO3) and ammonium phosphate (NH4H2PO4)] in combination with three levels of applied N–S ratios [8, 4, 2; S as potassium sulfate (K2SO4) and sodium sulphate (Na2SO4)] were tested as treatments. Results indicated that a significant response to seed yield was observed for N and S application. Maximum yield, 24.8 g pot−1, was found when full doses of N and S were applied. Increasing N supply from 0.5 g pot−1 to 1 g pot−1 had little increasing effect in the oil content of the seed. Higher application of N doses (>1 g pot−1) decreased these values significantly. The maximum oil content (28%) was achieved with the 1 g N pot−1 treatment; the lowest values were observed in the pots applied with the highest N doses. Changes in the N content of the seed and straw showed a statistically significant increase with increasing N and S fertilization. Highest values in the seed and straw (5.96% and 0.87%, respectively) were observed by applying highest N and S doses. Seed and straw S levels were also observed to increase with increasing N rates and decreasing N–S ratio. Nitrogen doses significantly improved the quantities of essential amino acids with the exception of threonine, tyrosine, phenylalanine, and methionine. The amounts of these amino acids decreased with increasing N supply. When the N–S ratio decreased by increasing S, the quantities of valine, isoleucine, leucine, lysine, methionine, and cysteine increased significantly and the amount of tyrosine decreased. The quantities of nonessential amino acids with the exception of proline, histidine, and glycine increased with increasing N doses. In contrast, N rates decreased the amount of glycine. Decreasing the N–S ratio lowered the proline and arginine contents. The total amounts of essential amino acids slightly increased with increasing N rates and decreasing N–S ratio.

Determination of sulphur in plant extracts by ion chromatograph - Hydraulic high-pressure nebulizer - Inductively coupled plasma atomic emission spectrometer (IC/HHPN/ICP-AES)

The method for speciation and quantitative analysis of inorganic sulphur form, sulphate and organic sulphur compounds by using high performance ion chromatography (IC) with inductively coupled plasma atomic emission spectrophotometry (ICP-AES) has been developed. An ICP-AES was operated as a detector of IC. To achieve a lower detection limit a hydraulic high-pressure nebulizer was used for connection between IC and ICP. This hyphenated system was used for the separation and determination of organic sulphur compounds and sulphate ions. By using an anion exchange column, with 2.5 mM phthalic acid, adjusted with TRIS to pH=4.2, all of the organic sulphur forms were measured together as a first (pseudo) peak (Nieto and Frankenberger, 1985) at 2.0 min., while the sulphate ion was retained on the column and its peak appeared with retention time at 4.2 min. Other inorganic sulphur forms (sulphide, sulphite, thiosulphate etc.) were not detectable in the water extracts from the examined plants. The sulphide and sulphite peaks were observed between the organic sulphur and sulphate peaks, but the developed method was not optimised for their separation. The sulphur was detected on the polychromator of ICP-AES on 180.734 nm. The detection limits were 0.023 mg L -1 and 0.085 mg L -1 of sulphate-sulphur and of organic-sulphur respectively. Water extracts of standard wheat straw and grain samples were analysed.Abstract The method for speciation and quantitative analysis of inorganic sulphur form, sulphate and organic sulphur compounds by using high performance ion chromatography (IC) with inductively coupled plasma atomic emission spectrophotometry (ICP‐AES) has been developed. An ICP‐AES was operated as a detector of IC. To achieve a lower detection limit a hydraulic high‐pressure nebulizer was used for connection between IC and ICP. This hyphenated system was used for the separation and determination of organic sulphur compounds and sulphate ions. By using an anion exchange column, with 2.5 mM phthalic acid, adjusted with TRIS to pH=4.2, all of the organic sulphur forms were measured together as a first (pseudo) peak (Nieto and Frankenberger, 1985) at 2.0 min., while the sulphate ion was retained on the column and its peak appeared with retention time at 4.2 min. Other inorganic sulphur forms (sulphide, sulphite, thiosulphate etc.) were not detectable in the water extracts from the examined plants. The sulphide and sulphite peaks were observed between the organic sulphur and sulphate peaks, but the developed method was not optimised for their separation. The sulphur was detected on the polychromator of ICP‐AES on 180.734 nm. The detection limits were 0.023 mg L‐1 and 0.085 mg L‐1 of sulphate‐sulphur and of organic‐sulphur respectively. Water extracts of standard wheat straw and grain samples were analysed.

Effects of fertilization, irrigation and crop rotation on the transition and toxic element uptake of corn

Abstract The effect of fertilization (NPK), irrigation and crop rotation on the transition and toxic element contents of maize (Pannonia hybrid) were studied. In the course of a field plot experiment, samples were taken at four growth stages. After wet digestion, plant samples were analyzed by ICP spectrometer. The effect of fertilization on the zinc, copper, manganese, iron and nickel content and that of irrigation on the copper, zinc and aluminium content are shown in this study. We observed the interrelationship between zinc and copper content and fertilizer rates in early phenophases. At the harvest stage the zinc content was the lowest with triculture. In latter stages the effect of crop rotation on the copper content was increasingly obvious. Fertilizers increased the manganese, iron and nickel content significantly in young plants. The manganese content of young plants was lowest with monoculture and highest with triculture. The nickel content of plants was lowest with triculture. The effect of irrigation was influenced by the crop rotation in the case of zinc, copper and aluminium content, but it affected the element content significantly only in 5-and 10-leaf stages.

Long-Term Effect of High Phosphorus Doses on Zinc Status of Maize on a Non-Calcareous Loamy Soil

The long-term effect of 87.3 kg/ha P on the yield elements and nutrient content of maize was studied at the Na tional Long-Term Fertilization Experiment of the Karcag Research Institute in Hungary. The soil of the experiment site is non-calcareous Luvic Phaeosem, and its soluble phosphorus (P) and zinc (Zn) content in 0–20 cm soil layer are: ammonium lactate P: 141.1 mg/kg and diethylene triamine pentaacetic acid (DTPA) Zn: 0.85 mg/kg, respectively. The effect of foliar Zn fertilization was studied at three levels of nitrogen (150, 200 and 250 kg/ha) and under 87.3 kg/ha P and 82.6 kg/ha K application in four replications. The applied Zn amount was 700 g/ha. We measured the grain yield and the thousand-kernel weight. Leaf and grain samples were analyzed for phosphorus, zinc, potassium, calcium, magnesium and manganese content. Foliar Zn application did not increase the yield significantly, but it enhanced the thousand-kernel weight. The element content did not change significantly – neither in leaves nor in kernels. Under the examined habitat circumstances even the long-term application of 87.3 kg/ha P dosage did not cause Zn deficiency to such an extent which would lead to significant yield depression of maize.