This study was conducted to study the optimum dosage of potassium ful- vate (PF) on greenhouse tomato, the effects of different amounts of PF on yield and quality of greenhouse tomato and soil physical and chemical ...This study was conducted to study the optimum dosage of potassium ful- vate (PF) on greenhouse tomato, the effects of different amounts of PF on yield and quality of greenhouse tomato and soil physical and chemical properties were investigated by a field plot experiment. The results showed that the bottom applica- tion of PF increased tomato yield, plant dry matter weight and root dry matter weight by 14.0%, 14.4 and 50.6%, respectively; Vc and soluble sugar content of tomato increased by 1&5% and 10.0%, respectively; and soil bulk density de- creased by 3.6%, and CEC increased by 5.0%. All the indexes increased with the increase of PF application amount, and reached the maximum value when the PF application rate was 4 500 kg/hm2. In consideration of the cost of fertilizer and all indexes, the optimum dosaqe of PF fertilizer was 4 500 kg/hm2.展开更多
The acid-base buffer characteristics of fulvic acid (FA) and barium fulvate (BaFA)were analyzed. Each share of the sample or model agents (phthalic acid and salicylic acid)were separately mixed into a series of shares...The acid-base buffer characteristics of fulvic acid (FA) and barium fulvate (BaFA)were analyzed. Each share of the sample or model agents (phthalic acid and salicylic acid)were separately mixed into a series of shares of dilute solutions of HCI or NaOH with a series of concentration. The original pH values of the solutions were arranged from 2 to 13.Final balanced pH of each share was measured. The pH changes show that FA and BaFApossess buffer ability, whereas the model agents do not. The tendency of balanced pHvalues was 5.4 for FA and 7.4 for BaFA, whereas the original pH was 4.0-8.5; balancedpH changed little. At room temperature, the maximum buffer capacities were as follows:18.11 mmol hydroxyl per gram FA, 11.25 mmol hydroxyl per gram BaFA, 1.19 mmol protonper gram FA, and 1.45 mmol proton per gram BaFA. Mathematics analysis shows thatlogarithm of buffer capacities of FA and BaFA is linearly dependent on original pH. Compared with BaFA and model agents, it is concluded that FA buffer capacity against hydroxylrelies not only on its acidic groups, BaFA buffer capacity against hydroxyl does not rely onits acidic groups, and FA buffer capacity against proton is not related with its carboxyl andphenolic hydroxyl group. The pH values of FA-water solutions with different concentrationsfrom 1 to 10 grams per liter were measured. Their pH values were slightly affected by itsconcentration. Thus, FA possesses a much stronger buffer ability against water dilutionthan common buffer agent. All the pH values of FA water solutions were very nearby 5.4,just the same as the balanced pH tendency for adding FA.展开更多
On the example of copper fulvate, it is discussed the method of calculation of stability constants of fulvic complexes. At pH = 8, the complex formation of copper(ll) ions with fulvic acids was studied by the solubi...On the example of copper fulvate, it is discussed the method of calculation of stability constants of fulvic complexes. At pH = 8, the complex formation of copper(ll) ions with fulvic acids was studied by the solubility method. Fulvic acids were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal (BAU, Russia) was used as a sorbent. The suspension of copper(If) hydroxide was used as the solid phase, on which was added the increasing quantity of standard solution of fulvic acids. In diluted solutions, at pH = 8 the dominant form of copper(lI) is copper dihydroxo complex Cu(OH)^zO. It was established that in the Cu(OH)2 (solid)-Cu(OH)^20 (solution)-FA^2-H20 system, dominates copper dyhydroxo fulvate complex with the structure 1:1, [Cu(OH)2FA]^2. The average stability constant of copper dyhydroxo fulvate complex was calculated based on experimental data fl [Cu(OH)2FAJ^2 = 4.5× l0^5.展开更多
At pH = 8, the complex formation process of Ni(Ⅱ) ions with FA was studied by the solubility method. FA were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal (BAU, Russia) w...At pH = 8, the complex formation process of Ni(Ⅱ) ions with FA was studied by the solubility method. FA were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal (BAU, Russia) was used as a sorbent. The old suspension of Ni(Ⅱ) hydroxide was used as the solid phase, on which was added the increasing quantity of standard solution of FA. In diluted solutions, at pH = 8.0 the dominant form of Ni(Ⅱ) is nickel dihydroxocomplex Ni(OH)2^0. It was established that in the Ni(OH)2(solid)-Ni(OH)2^0(solution)-FA2-H20 system dominates nickel dyhydroxofulvate complex with the structure 1:1, [Ni(OH)2FA]2-. The average stability constant of nickel dyhydroxofulvate complex was calculated based on experimental data flNi(OH)2FA2" = 5.3 × 105.展开更多
文摘This study was conducted to study the optimum dosage of potassium ful- vate (PF) on greenhouse tomato, the effects of different amounts of PF on yield and quality of greenhouse tomato and soil physical and chemical properties were investigated by a field plot experiment. The results showed that the bottom applica- tion of PF increased tomato yield, plant dry matter weight and root dry matter weight by 14.0%, 14.4 and 50.6%, respectively; Vc and soluble sugar content of tomato increased by 1&5% and 10.0%, respectively; and soil bulk density de- creased by 3.6%, and CEC increased by 5.0%. All the indexes increased with the increase of PF application amount, and reached the maximum value when the PF application rate was 4 500 kg/hm2. In consideration of the cost of fertilizer and all indexes, the optimum dosaqe of PF fertilizer was 4 500 kg/hm2.
文摘The acid-base buffer characteristics of fulvic acid (FA) and barium fulvate (BaFA)were analyzed. Each share of the sample or model agents (phthalic acid and salicylic acid)were separately mixed into a series of shares of dilute solutions of HCI or NaOH with a series of concentration. The original pH values of the solutions were arranged from 2 to 13.Final balanced pH of each share was measured. The pH changes show that FA and BaFApossess buffer ability, whereas the model agents do not. The tendency of balanced pHvalues was 5.4 for FA and 7.4 for BaFA, whereas the original pH was 4.0-8.5; balancedpH changed little. At room temperature, the maximum buffer capacities were as follows:18.11 mmol hydroxyl per gram FA, 11.25 mmol hydroxyl per gram BaFA, 1.19 mmol protonper gram FA, and 1.45 mmol proton per gram BaFA. Mathematics analysis shows thatlogarithm of buffer capacities of FA and BaFA is linearly dependent on original pH. Compared with BaFA and model agents, it is concluded that FA buffer capacity against hydroxylrelies not only on its acidic groups, BaFA buffer capacity against hydroxyl does not rely onits acidic groups, and FA buffer capacity against proton is not related with its carboxyl andphenolic hydroxyl group. The pH values of FA-water solutions with different concentrationsfrom 1 to 10 grams per liter were measured. Their pH values were slightly affected by itsconcentration. Thus, FA possesses a much stronger buffer ability against water dilutionthan common buffer agent. All the pH values of FA water solutions were very nearby 5.4,just the same as the balanced pH tendency for adding FA.
文摘On the example of copper fulvate, it is discussed the method of calculation of stability constants of fulvic complexes. At pH = 8, the complex formation of copper(ll) ions with fulvic acids was studied by the solubility method. Fulvic acids were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal (BAU, Russia) was used as a sorbent. The suspension of copper(If) hydroxide was used as the solid phase, on which was added the increasing quantity of standard solution of fulvic acids. In diluted solutions, at pH = 8 the dominant form of copper(lI) is copper dihydroxo complex Cu(OH)^zO. It was established that in the Cu(OH)2 (solid)-Cu(OH)^20 (solution)-FA^2-H20 system, dominates copper dyhydroxo fulvate complex with the structure 1:1, [Cu(OH)2FA]^2. The average stability constant of copper dyhydroxo fulvate complex was calculated based on experimental data fl [Cu(OH)2FAJ^2 = 4.5× l0^5.
文摘At pH = 8, the complex formation process of Ni(Ⅱ) ions with FA was studied by the solubility method. FA were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal (BAU, Russia) was used as a sorbent. The old suspension of Ni(Ⅱ) hydroxide was used as the solid phase, on which was added the increasing quantity of standard solution of FA. In diluted solutions, at pH = 8.0 the dominant form of Ni(Ⅱ) is nickel dihydroxocomplex Ni(OH)2^0. It was established that in the Ni(OH)2(solid)-Ni(OH)2^0(solution)-FA2-H20 system dominates nickel dyhydroxofulvate complex with the structure 1:1, [Ni(OH)2FA]2-. The average stability constant of nickel dyhydroxofulvate complex was calculated based on experimental data flNi(OH)2FA2" = 5.3 × 105.