Assessment of natural radionuclides content in humate-containing fertilizers

Analytical constraints on acidic functional groups in humic substances

Nature differences of humic acids fractions induced by extracted sequence as explanatory factors for binding characteristics of heavy metals

Humic acids (HAs) determine the distribution, toxicity, bioavailability, and ultimate fate of heavy metals in the environment. In this work, ten HA fractions (F1-F10) were used as adsorbent, which were sequentially extracted from natural sediments of Lake Wuliangsuhai, to investigate the binding characteristics of Cu2+ to HA. On the basis of the characterization results, differences were found between the ten extracted HA fractions responding to their elemental compositions and acidic functional groups. The characterization results reveal that the responses of ten extracted HA fractions to their elemental compositions and acidic functional groups were different. The O/C and (O+N)/C ratio of F1-F8 approximately ranged from 0.66 to 0.53 and from 0.72 to 0.61, respectively; the measured results showed that the contents of phenolic groups and carboxyl groups decreased from 4.46 to 2.60mmol/g and 1.60 to 0.58mmol/g, respectively. The binding characteristics of Cu2+ to the ten HA fractions were well modeled by the bi-Langmuir model; the binding behavior of Cu2+ to all the ten HA fractions were strongly impacted by pH and ionic strength. The FTIR and SEM-EDX image of HA fractions (pre- and post-adsorption) revealed that carboxyl and phenolic groups were responsible for the Cu2+ sorption on the ten sequentially extracted HA fractions process, which is the same with the analysis of the ligand binding and bi-Langmuir models Accordingly, the adsorption capacity of the former HA fractions on Cu2+ were higher than the latter ones, which may be attributed to the difference of carboxyl and phenolic group contents between the former and latter extracted HA fractions. Additionally, the functional groups with N and S should not be neglected. This work is hopeful to understand the environmental effect of humic substances, environmental geochemical behavior, and bioavailability of heavy metals in lakes.

Insight into the interaction mechanism of iron ions with soil humic acids. The effect of the pH and chemical properties of humic acids.

Effects of selected chemical and physicochemical properties of humic acids from peat soils on their interaction mechanisms with copper ions at various pHs

CHARACTERIZATION OF THE DISSOLVED ORGANIC CARBON IN LANDFILL LEACHATE-POLLUTED GROUNDWATER

Acid–base titration curves of solid humic acids

Spectroscopic properties of humic acids isolated from the rhizosphere and bulk soil compartments and fractionated by size-exclusion chromatography

Summary We studied the acid‐base properties of 16 fulvic acids and 16 humic acids isolated from the surface (3–15 cm) and subsurface (> 45 cm) horizons of two types of acid forest soils, derived respectively from amphibolite and granite rocks, under five different types of vegetation. The observed differences between the contents of humic substances in the two types of soils were related to the degree of Al‐saturation of the soil organic matter, as indicated by the molar ratio between pyrophosphate extractable Al and C. Humic fractions were characterized in terms of elemental composition, and CPMAS 13 C NMR spectrometry. The contents of carboxylic and phenolic groups were estimated by potentiometric titrations conducted in 0.1 m KNO 3 in a nitrogen atmosphere. The fulvic acids contained more carboxylic groups but less phenolic groups than the humic acids: the ratio of phenolic to carboxylic groups in the humic acids was 0.48 ± 0.10 and in the fulvic acids 0.23 ± 0.05. The mean values of the protonation constants of each of the humic substance fractions can be used as generic parameters for describing the proton binding properties. The fulvic acids isolated from the subsurface horizon of the soil contained between 2.6 and 23% more carboxylic groups, and the humic acids between 8 and 43% more carboxylic groups than those isolated from the surface horizon of the same soil.

Zinc release by humic and fulvic acid as influenced by pH, complexation and DOC sorption

ABSTRACTExtract and analysis of the Dissolved Organic Carbon (DOC) fractions were analyzed from the leachate of an uncontrolled dumpsite at Gohagoda, Sri Lanka. DOC fractions, humic acid (HA), fulvic acid (FA) and the hydrophilic (Hyd) fractions were isolated and purified with the resin techniques. Spectroscopic techniques and elemental analysis were performed to characterize DOCs. Maximum TOC and DOC values recorded were 56,955 and 28,493 mg/L, respectively. Based on the total amount of DOC fractionation, Hyd dominated accounting for ∼60%, and HA and FA constituted ∼22% and ∼17%, respectively, exhibiting the mature phase of the dumpsite. The elemental analysis of DOCs revealed carbon variation following HA > FA > Hyd, while hydrogen and nitrogen were similar in each fraction. The N/C ratio for HA was recorded as 0.18, following a similar trend in old dumpsite leachate elsewhere. The O/C ratios for HA and FA were recorded higher as much as 1.0 and 9.3, respectively, indicating high degree of carbon mineralization in the leachates. High content of carboxylic, phenolic and lactone groups in all DOCs was observed disclosing their potential for toxic substances transportation. The results strongly suggest the risk associated with DOCs in dumpsite leachate to the aquatic and terrestrial environment.

Coffee husk waste ranges from 40-45% of wet coffee. In addition, the Coffee leather content is still quite good, namely 10.4% crude protein, 17.2% crude fiber. Liquid fertilizer from red cherry coffee pods with a mixture of local raw materials can be used as liquid organic fertilizer to increase coffee production. The objectives of this study were (1) to describe community empowerment in utilizing coffee husk waste and local raw materials available in the village as raw material for liquid fertilizer, (2) to describe the strategy for developing liquid fertilizer from the coffee rind and local raw materials to increase coffee production. robusta in the village of Tribudisyukur, West Lampung. The method used in this study is a qualitative approach with data collection from the literature, observations, interviews and documentation, and SWOT analysis. The results of this study indicate that the people of Tribudisyukur village can use coffee rind waste and local raw materials as liquid fertilizers for coffee cultivation and horticultural crops. Based on the results of the analysis on the SWOT matrix, the recommendation that must be given is the “Progressive” strategy. Alternative strategies for developing liquid organic fertilizers that can be applied are (1) Utilizing quality raw material products (perfectly ripe) as a potential market share which is still widely supported by increasing public interest in organic products and creating new jobs due to the wider market. (2) Cultivating plants that have the potential for fruit rich in nutrients for the availability of nutrients and ecosystem sustainability and to streamline the cost of coffee cultivation.

Results of the structural and functional composition of soil humus acids in the Euro-Arctic Region are presented. The molecular absorption spectroscopy (UV / visible) was used to evaluate eco-protective role of soils in relation to heavy metals, which is especially important for the sensitive soils of the Arctic, formed under the influence of cryogenic processes. Different types of soils of the Euro-Arctic region: gleyish easy loamy pelosi on loamy moraine (Kanin Peninsula, Cape Kanin Nos); humus peat oligotrophic soil (Kolguev Island, Bugrino village); typical non-calcic loamy gley soil (Vaigach Island); gray humous iron sandy lithozem (Archipelago Franz Josef Land, Heys Island) were analyzed. An alkaline solution of sodium pyrophosphate was used to extract humus acids for investigate of the structural and functional composition. Humic, fulvic and gimatomelanic acids were extracted from a humus by conforming solvents with additional fulvic acids extraction by adsorption chromatography using activated carbon as a sorbent. UV mini-1240 spectrophotometer (Shimadzu) was used to record the UV / visible spectra using 0.005% alkaline solutions (0.1 N NaOH) of humus acids. It was demonstrated that humic and gimatomelanoic acids of humus peat oligotrophic soil have more developed peripheral aliphatic component. These acids have more ability to bind heavy metals and show their eco-protective role. The humus acids of other types of soils region have a more developed aromatic component in the Euro-Arctic. Such parameters as: calculated by the Pieravuori formula aromaticity, extinction coefficient Е0.005%1cm,465, adsorption ratio D400 /D600, characterizing the degree of humification and the adsorption ratio D465 / D650, characterizing the degree of aromatic nucleus condensation and conjugate fragments were used in the quantitative assessment of the nature of humus acids. Quantitative analysis of UV/visible spectra confirmed that the maximum barrier mechanism with respect to heavy metals will be the humic and gimatomelanoic acids of humus-peat oligotrophic soil, due to the high content of phenolic and carboxyl groups in these molecules, oxidation and a more developed chain of conjugated bonds in them in comparison with other acids. However, it was found that in all types of soils studied the process of humus formation proceeds mainly by a degradation type, that is, in the direction of formation of fulvic acids. Forcitation:Prilutskaya N.S., Korel'skaya T.A., Popova L.F. Study of structural and functional composition of soil humus acids of euro-arctic region by molecular absorption spectroscopy (UV / visible). Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 2. P. 97-103

The dynamics of interaction between metallic iron and aqueous solutions of three preparations of humic coal substances from different manufacturers is analyzed. Humic substances are characterized via elemental analysis, NMR spectroscopy, size-exclusion chromatography, electronic absorption spectroscopy, and chemical analysis. Distinctions are observed between the investigated humic substances in the content of aromatic moieties, the degree of their substitution, the content of carboxylic groups, and the degree of oxidation. It is shown that regardless of the background of humic substances, the interaction between their solutions and iron is based on the same set of consecutive reactions, which can be divided into three basic stages of interaction using data on the changes in easily controllable parameters (redox potential, pH, and solution absorbance). These stages of interaction are qualitatively described in Pourbaix diagram coordinates. Features of the structural and group composition of humic substances result in different times of the corresponding stages of interaction. Based on an analysis of the main components, a way of describing the complicated sequence of reactions between humic substances and iron in the coordinates of a two-factor plane is proposed to allow the clear attribution of experimentally measured parameters of the reaction medium to a certain stage of interaction between metallic iron and aqueous solutions of humic substances, regardless of the specific properties of the latter.

Fusarium wilt disease presents a significant menace to tomato plants, necessitating effective preventative measures. Five isolates of Fusarium oxysporum f.sp. lycopersici from infected tomato plants from different regions in Missan province, each showing varying levels of pathogenicity. Differences in the ability of tomato seedlings to be infected by these isolates were also observed during a pot experiment, ranging from highly pathogenic to non-pathogenic. To address this issue, the efficacy of the bioagent Chaetomium globosum and humic acid in controlling the pathogenic fungus F. oxysporum f.sp. lycopersici and improving the growth indicators of tomato plants in the presence of the causative fungus. Two concentrations of humic acid (8 and 4 mL/l) were tested to determine their efficacy in reducing the growth of pathogenic fungi in vitro. We found that the growth of the pathogenic fungi decreased to 41.06% at a concentration of 8 ml/l, compared to the control, which showed no growth. Moreover, when used alone or in combination with humic acid, C. globosum significantly reduced the percentage and severity of infection. The treatment involving the interaction between the bioagent and humic acid at a concentration of 8 ml/l recorded an infection percentage of 14.4% and an infection severity of 11.87%, compared to the pathogenic fungus treatment that resulted in 53% infection and 43.80% severity, respectively. Moreover, the use of C. globosum and different concentrations of humic acid raised all growth indices in all treatments whether in the presence or absence of pathogenic funus. These improvements included increased fresh and dry weight of the shoot and root, enhanced plant height and leaf area, as well as a significant increase in the content of total phenols and total chlorophyll in the leaves. The findings of this study highlight the potential of C. globosum and humic acid as effective control measures against fusarium wilt disease in tomato plants. The results indicate their ability to suppress the pathogenic fungus and promote plant growth. These findings hold promise for the development of sustainable agricultural practices.