Application Of Organic Materials Research Articles

Organic waste recycling application increases N availability and mitigates N2O emission without crop yield penalty in the North China Plain

IntroductionAgricultural organic waste recycling can supply nutrients for crop production and partially replace chemical nitrogen fertilizers, which is beneficial for waste management and environmental protection. Nevertheless, comprehensive evaluation of the effects of different organic materials applications on crop yield and the environment is limited.MethodsTherefore, in this study, a comprehensive investigation of the synergistic effects of straw, pig manure, and biogas residue recycling on the wheat (Triticum aestivum L.) and maize (Zea mays L.) systems was carried out in the North China Plain. Field experiments were conducted from 2019 to 2021, comprising five treatments: straw (ST), pig manure (PM), and biogas residue (BR) partially replacing chemical nitrogen fertilizer, sole application of chemical nitrogen fertilizer (CF), and a control with no nitrogen application (WN).Results and discussionThe results showed that organic materials significantly increased soil total nitrogen (3.04%–9.10%) and N recovery efficiency (REN; 42.21%–44.99%), but pig manure was more beneficial in increasing crop yields (3.50%), especially wheat yields (8.72%), and REN was significantly higher than that of the other treatments. Organic materials performed differently in wheat and maize seasons, and wheat yield could be improved by organic materials return. Organic materials stimulated N2O emission in wheat season (4.28%–32.20%), while biogas residue inhibited the N2O emission in maize season (47.47%). The negative effect of straw and biogas residue on yield decreased with increasing years of return, and pig manure continued to contribute to yield. In conclusion, pig manure is the optimal alternative that can increase crop yield, soil N content, and REN without stimulating N2O emissions.

C–X (X = C, O, S, N, B, P) Bond Deuteration and Late‐Stage Applications

Precise deuterium labeling has gained significant attentions owing to the wide applications in organic synthesis, medicinal chemistry, and organic materials. C−C and C−heteroatom bonds constitute the skeleton of organic molecules. This review summarizes the advancements on C−C and C−heteroatom bond deuterations as well as their applications in late‐stage deuterations of natural products and pharmaceutically relevant molecules.

Distinction of facilitating effects between dissolved organic matter derived from corn straw and fulvic acid on transport of titanium dioxide nanoparticles in saturated sand: Dependent on the solution chemistry

The application of organic materials into agricultural soil introduces dissolved organic matter (DOM) into environment. The DOM derived from organic materials would significantly affect the environmental behaviors of nanoparticles. In this study, DOM extracted from corn straw (CSDOM) was characterized and its effects on the transport of titanium dioxides nanoparticles (TiO2 NPs) in porous media were evaluated and compared with those of fulvic acid (FA). The characterization of DOMs indicated marked differences in molecular properties between CSDOM and FA. Weight-average molecular weight (Mw) of CSDOM was 3139 g/mol, higher than 1185 g/mol of FA, whereas CSDOM had a lower aromaticity than FA. Three distinct scenarios of nanoparticle mobility affected by CSDOM and FA were found. Under unfavorable conditions for nanoparticles mobility (pH 4.0 with/without electrolytes, pH 7.0 with electrolytes, and pH 10.0 with CaCl2), both DOMs facilitated TiO2 NPs mobility, and FA with higher aromaticity exerted stronger enhancing effects than CSDOM. However, the promoting effects of DOM on TiO2 NPs mobility were negligible under favorable conditions (pH 10.0 without electrolytes). Under the remaining conditions (pH 7.0 without electrolytes, and pH 10.0 with NaCl), DOM could facilitate the mobility of TiO2 NPs, while there was no difference in the facilitating effects between CSDOM and FA. It could be concluded that distinction of enhancing effects between CSDOM and FA on TiO2 NPs mobility was environmental chemistry-dependent. Furthermore, aromaticity rather than Mw would be a reasonable property determining the enhancing effects of DOM derived from distinct sources on nanoparticle mobility under unfavorable conditions.

KOH-Mediated Synthesis of Substituted Isothiazoles via Two-Component Annulation with Dithioate and Aryl Acetonitrile.

We report a simple synthetic method for obtaining 3-hydroxy-4,5-disubstituted isothiazoles utilizing dithioester and aryl acetonitrile. The isothiazoles obtained in this method involve the formation of new C-C, C-O, and N-S bonds in one step using a simple base such as KOH under aerial conditions. The 3-hydroxy-4,5-disubstituted isothiazole was successfully employed for further functionalization. The strategy provides high selectivity for the synthesis of isothiazoles, which may have applications in pharmaceuticals, organic materials, and agrochemicals in both academic and industrial settings.

CNTs/Gr composite sandwich layered rare earth phthalocyanines MPcs (M = Yb, La) used as improved energy storage behaviors for lithium-ion batteries

To address the problem of aggregation and low electrical conductivity of rare earth phthalocyanines MPc (M = Yb, La), four composites are obtained by applying a physical method to combine two rare earth phthalocyanines with Gr/CNTs. These composites of rare earth phthalocyanines with Gr/CNTs effectively reduce the aggregation of phthalocyanine conjugated units and enhance the electrical conductivity. The electrochemical testing exhibits that the YbPc/CNTs electrode delivers a specific capacity of 1447 mAh/g after 275 cycles at a current density of 100 mA/g, demonstrating a capacity retention of 157.5 %. Similarly, the primitive specific capacity of LaPc/CNTs electrode is increasing from 515 mAh/g to 753 mAh/g at 100 mA/g after 400 cycles. Likewise, YbPc/Gr and LaPc/Gr electrodes have specific capacity of 912 mAh/g and 667 mAh/g after 450 cycles and 356 cycles, revealing capacity retention of 152 % and 74 %. It can be noted that compounding with Gr/CNTs can successfully solve the problems of a few exposures of redox-active sites caused by the aggregation of phthalocyanine conjugate units and poor rate performance owing to the sluggish ion/electrons transport of phthalocyanine, which furnishes a promising perspective for practical research and application of new organic anode materials in the field of superior electrochemical performance lithium-ion batteries.

Long-term application of organic matter improves soil properties and plant growth-promoting bacteria in soil communities of oil palm plantation

ABSTRACT Oil palm (Elaeis guineensis) is a major contributor to global vegetable oil production; however, ensuring its sustainability remains a critical challenge, particularly concerning soil health. In this study, we investigated the impact of long-term organic matter application as part of good soil management (GSM) practices on oil palm plantations and compared it with poor soil management practices to determine the presence of plant growth-promoting bacteria (PGPB) in soil communities. The ten-years regular application of organic matter to the soil in the GSM plots led to notable improvements in soil chemical properties, including total organic carbon, total nitrogen, available phosphorus, available potassium, and cation exchange capacity. Metagenomic analysis revealed a significantly higher abundance of beneficial microbial species exclusively found in GSM plots, supporting oil palm growth. Furthermore, a novel finding emerged from this study, as it successfully predicted the metabolic function of PGPB in soil communities using PICRUST2 provided by the soil microbiome. PICRUST2 analysis indicated that the long-term application of organic matter in GSM plots increased functional enzymes related to PGP activities, such as nitrogen fixation, phosphate solubilization, potassium solubilization, and phytohormone synthesis. This study underscores the significance of implementing GSM practices in oil palm plantations by incorporating eco-friendly materials, such as organic matter, to enhance soil health and fertility and ensure oil palm sustainability.

Lowering Chemical Fertilizers Rate in ‘Black Amber’ Plum Orchard for Improving Sustainable Resource Management: Effect on Soil Health and Fruit Quality

ABSTRACT The combined application of chemical fertilizers and organic material is a transitional approach toward more sustainable and productive farming. This study aimed to investigate the response of low chemical fertilizer rates and supplementing with organic materials on soil health and fruit quality. In plum orchard, combination of reduced chemical fertilizer rates (R80; R70; R60) with organic manures (F; V) at varying levels based the loss in nitrogen requirement and microbial inoculants (Bf; J) were studied over the conventional approach (R100) on soil health and fruit quality in a 2-year experiment. Soil analysis showed soil physico-chemical properties and enzymes activity with application of R70+V10+Bf. Compared to integrated treatments R100 saw highest availability of soil potassium and calcium. Application of R70+V10+J resulted in maximum improvement in fruit weight, TSS and soluble sugar content. Fruit set percentage was higher in treatment R70+V10+Bf. Fruit yield showed significant changes with treatments R70+V10+Bf and R70+V10+J having similar yield to R100. Our results suggest that by reducing the amount of chemical fertilizer by 30% and partially replacing it with organic materials had a positive effect on soil health without affecting the fruit production and quality.

Polymer Materials for Optoelectronics and Energy Applications.

This review comprehensively addresses the developments and applications of polymer materials in optoelectronics. Especially, this review introduces how the materials absorb, emit, and transfer charges, including the exciton-vibrational coupling, nonradiative and radiative processes, Förster Resonance Energy Transfer (FRET), and energy dynamics. Furthermore, it outlines charge trapping and recombination in the materials and draws the corresponding practical implications. The following section focuses on the practical application of organic materials in optoelectronics devices and highlights the detailed structure, operational principle, and performance metrics of organic photovoltaic cells (OPVs), organic light-emitting diodes (OLEDs), organic photodetectors, and organic transistors in detail. Finally, this study underscores the transformative impact of organic materials on the evolution of optoelectronics, providing a comprehensive understanding of their properties, mechanisms, and diverse applications that contribute to advancing innovative technologies in the field.

Amended soils with weathered coal exhibited greater resistance to aggregate breakdown than those with biochar: From the viewpoint of soil internal forces

Soil erosion is the first threat to soil functions. Reducing the soil aggregate breakdown strength is a key step to improve the soil’s ability to resist rainfall splash erosion. Soil internal forces have been found to be the initial and important forces driving aggregate turnover. The application of exogenous organic materials can effectively improve soil aggregate stability and the resistance to rainfall erosion of agricultural soils. However, from the perspective of soil internal forces, information about the reduction effects of the exogenous organic materials application on soil aggregate breakdown is scarce, especially in comparing the effects of different materials. In this study, weathered coal and biochar were individually applied to loamy clay soil at rates of 0 %, 1 %, 2 %, and 3 % (w/w). Soil internal forces, aggregate breakdown strength, and splash erosion rate of different amended soils were then examined after four years. The results showed that compared with unamended soils (0 %), both weathered coal and biochar applications clearly increased the van der Waals attractive pressure and thus decreased the positive net pressure between soil particles. Additionally, these materials reduced soil aggregate breakdown strength and splash erosion rate. The application effects of the two materials were increased with their application rates. Under a lower electrolyte concentration in soil solution (0.0001 mol L−1), the aggregate breakdown strength in the soils amended with weathered coal was lower than that with biochar by 9.6 %, 23.2 %, and 17.7 % (when the diameter of broken aggregate was < 10 μm) and by 10.3 %, 20.8 %, and 17.5 % (when the diameter of broken aggregate was < 20 μm) at the 1 %, 2 %, and 3 % application rates, respectively (P < 0.05). Additionally, soils amended with weathered coal exhibited lower splash erosion rates compared to those amended with biochar, particularly at the higher application rate of 3 %. From the viewpoint of soil internal forces, weathered coal appears to be a suitable exogenous organic material for improving soil aggregate stability and anti-erosion ability during rainfall events. Our findings provide valuable insights into utilizing exogenous materials to improve soil resistance to rainfall splash erosion, assisting agricultural soil management in areas frequently affected by rainfall erosion.

Development of bacteria-based bioorganic phosphate fertilizer enriched with rock phosphate for sustainable wheat production.

Phosphorous (P) is a limiting macronutrient for crop growth. Its deficiency prevents plant development leading to an extensive use of phosphatic fertilizers globally. Bio-organic phosphate (BOP) fertilizer provides a sustainable approach to optimize nutrient availability, enhance crop yield, and mitigate the negative impacts of chemical fertilizers on the environment. Therefore, the present study integrates the application of heat-tolerant phosphate-solubilizing bacteria, rock phosphate, and organic materials for the development of BOP. For this purpose, potential heat-tolerant phosphate-solubilizing bacteria (PSB) were isolated from major wheat-growing areas of southern Punjab. Five isolates were the efficient phosphate solubilizers based on in vitro phosphate-solubilizing activity (291-454 μg ml-1 and 278-421 μg ml-1) with a concomitant decrease in pH (up to 4.5) at 45°C and 50°C, respectively. These PSB were used for the development of potential consortia that are compatible and showed high P solubilization. In planta evaluation of these PSB consortia in a pot experiment under net house conditions showed that consortium-2 had a favorable impact on growth parameter with enhanced grain yield (9.63 g plant-1) and soil available P (10 μg g-1) as compared with 80% uninoculated control. The microcosm study was conducted to evaluate PSB consortium-2 integrated with carrier material (plant material and filter mud) and rock phosphate as BOP increased total phosphorous (14%) as compared with uninoculated controls. Plant-based BOP showed higher viable count (3.5 × 108°CFU) as compared with filter mud-based BOP. Furthermore, the effect of BOP on wheat growth parameters revealed that BOP showed a promising influence on grain yield (4.5 g plant-1) and soil available P (10.7 μg g-1) as compared with uninoculated 80 and 100% controls. Principle component analysis (PCA) further validates a positive correlation between BOP with grain weight and plant height and soil available P as compared with both 80 and 100% controls. For the first time, this study reports the combined application of bio-organic phosphate fertilizer and heat-tolerant PSB, which offers an eco-friendly option to harvest better wheat yield with low fertilizer input.

Small-molecule organic electrode materials on carbon-coated aluminum foil for high-performance sodium-ion batteries

Organic molecular electrode materials are promising candidates in batteries. However, direct application of small molecule materials usually suffers from drastic capacity decay and inefficient utilization of active materials because of their high solubility in organic electrolytes and low electrical conductivity. Herein, a simple strategy is found to address the above issues through coating the small-molecule organic materials on a commercialized carbon-coated aluminum foil (CCAF) as the enhanced electrode. Both the experimental and calculation results confirm that the relatively rough carbon coating on the aluminum foil not only exhibits superior adsorption capacity of small-molecule organic electrode materials with a tight contact interface but also provides continuous electronic conduction channels for the facilitated charge transfer and accelerated reaction kinetics. In addition, the carbon coating also inhibits Al corrosion in electrochemical process. As a result, by using the tetrahydroxy quinone-fused aza-phenazine (THQAP) molecule as an example, the THQAP-CCAF electrode exhibits an excellent rate performance with a high capacity of 220 and 180 mAh g−1 at 0.1 and 2 A/g, respectively, and also a remarkable cyclability with a capacity retention of 77.3% even after 1700 cycles in sodium-ion batteries. These performances are much more superior than that of batteries with the THQAP on bare aluminum foil (THQAP-AF). This work provides a substantial step in the practical application of the small-molecule organic electrode materials for future sustainable batteries.

Ecological justification for the effectiveness of recycling organic matter from waste to increase the primary production of cultivated plants

The article shows that the method of recycling liquid and solid organic substances obtained as a by-product during the production of biogas from organic waste and composting organic waste with the addition of liquid organic matter in the agroecosystem on ordinary chernozem in the Orenburg Oblast is effective. The standards for the application of liquid and solid organic substances were studied using an indicator culture. Data on the net primary productivity of the agroecosystem are presented. It was found that the reaction of the agroecosystem is more effective in the variant with liquid organic substances. Net primary productivity using the example of potatoes with a rate of application of liquid organic matter of 8 t/ha is 36,97% higher than with the background and application of solid organic matter, and amounted to 22,6 t/ha. They showed that the established standards for the utilization of liquid organic substances are 10 t/ha and solid organic substances are 5 t/ha.

Dual Roles of the Photooxidation of Organic Amines for Enhanced Triplet-Triplet Annihilation Upconversion in Nanoparticles.

Oxygen-mediated triplet-triplet annihilation upconversion (TTA-UC) quenching limits the application of such organic upconversion materials. Here, we report that the photooxidation of organic amines is an effective and versatile strategy to suppress oxygen-mediated upconversion quenching in both organic solvents and aqueous solutions. The strategy is based on the dual role of organic amines in photooxidation, i.e., as singlet oxygen scavengers and electron donors. Under photoexcitation, the photosensitizer sensitizes oxygen to produce singlet oxygen for the oxidation of alkylamine, reducing the oxygen concentration. However, photoinduced electron transfer among photosensitizers, organic amines, and oxygen leads to the production of superoxide anions that suppress TTA-UC. To observe oxygen-tolerating TTA-UC, we find that alkyl secondary amines can balance the production of singlet oxygen and superoxide anions. We then utilize polyethyleneimine (PEI) to synthesize amphiphilic polymers to encapsulate TTA-UC pairs for the formation of water-dispersible, ultrasmall, and multicolor-emitting TTA-UC nanoparticles.

Organic Electro-Optic Materials with High Electro-Optic Coefficients and Strong Stability.

The preparation of high-performance electro-optical materials is one of the key factors determining the application of optoelectronic communication technology such as 5G communication, radar detection, terahertz, and electro-optic modulators. Organic electro-optic materials have the advantage of a high electro-optic coefficient (~1000 pm/V) and could allow the utilization of photonic devices for the chip-scale integration of electronics and photonics, as compared to inorganic electro-optic materials. However, the application of organic nonlinear optical materials to commercial electro-optic modulators and other fields is also facing technical bottlenecks. Obtaining an organic electro-optic chromophore with a large electro-optic coefficient (r33 value), thermal stability, and long-term stability is still a difficulty in the industry. This brief review summarizes recent great progress and the strategies to obtain high-performance OEO materials with a high electro-optic coefficient and/or strong long-term stability. The configuration of D-π-A structure, the types of materials, and the effects of molecular engineering on the electro-optical coefficient and glass transition temperature of chromophores were summarized in detail. The difficulties and future development trends in the practical application of organic electro-optic materials was also discussed.

Light-driven C–H activation mediated by 2D transition metal dichalcogenides

C–H bond activation enables the facile synthesis of new chemicals. While C–H activation in short-chain alkanes has been widely investigated, it remains largely unexplored for long-chain organic molecules. Here, we report light-driven C–H activation in complex organic materials mediated by 2D transition metal dichalcogenides (TMDCs) and the resultant solid-state synthesis of luminescent carbon dots in a spatially-resolved fashion. We unravel the efficient H adsorption and a lowered energy barrier of C–C coupling mediated by 2D TMDCs to promote C–H activation and carbon dots synthesis. Our results shed light on 2D materials for C–H activation in organic compounds for applications in organic chemistry, environmental remediation, and photonic materials.

Exogenous calcium-induced carbonate formation to increase carbon sequestration in coastal saline-alkali soil

Promoting soil carbon sequestration is a possible way to mitigate global warming. To investigate the effects of exogenous calcium on soil carbon sequestration during the application of organic matter to improve coastal saline-alkali soil. In this study, a 30-day incubation experiment was based on the application of corn straw biochar + chicken manure (BM) and rice straw + chicken manure (SM). Usages of exogenous calcium in each treatment under each organic matter combination as follow: CK (No exogenous calcium), CaSi1 (1.24 g CaSiO3, i.e. 4.28 g Ca kg−1 soil), CaSi2 (2.48 g CaSiO3, i.e. 8.56 g Ca kg−1 soil), CaOH1 (0.79 g Ca(OH)2, i.e. 4.28 g Ca kg−1 soil), CaOH2 (1.58 g Ca(OH)2, i.e. 8.56 g Ca kg−1 soil), CaSiOH (1.24 g CaSiO3 + 0.79 g Ca(OH)2, i.e. 8.56 g Ca kg−1 soil). Results showed that exogenous calcium significantly reduced CO2 emission. Organic matter addition promoted the loss of SOC, and exogenous did not significantly affect the mineralization of SOC albeit strongly increased SIC, making up for the loss of SOC, increasing soil total carbon and realizing soil carbon fixation. Soil carbon fixation was mainly realized by the reaction of exogenous calcium with CO2 generated by mineralization and converting it into calcium carbonate. pH and soil CO2 emission are the major controlling factors for soil inorganic carbon sequestration. Therefore, applying organic matter with exogenous calcium can realize soil carbon fixation by generation of calcium carbonate.

Soil Acidity Causes in Ethiopia, Consequences and Mitigation Strategies-A Review

Soil acidity is a serious land degradation problem and worldwide danger, impacting approximately 50% of the world's arable soils and limiting agricultural yield. Soil acidification is a complicated series of events that lead to the production of acidic soil. In its widest sense, it can be defined as the total of natural and human processes that reduce the pH of soil solutions. Soil acidity affects around 43% of agricultural land in Ethiopia's humid and sub humid highlands. Acid soils in western Ethiopia are mostly caused by topsoil erosion caused by heavy rains and high temperatures. This results in the loss of organic matter and the leaching of exchangeable basic cations (Ca2+, Mg2+, Na+, and K+). Because ammonium-based fertilizers are easily converted to nitrate and hydrogen ions in the soil, they play a significant role in acidification. One of the reasons of soil acidity is inefficient nitrogen usage, which is followed by alkalinity exports in crops. Soil acidity in Ethiopian highlands is mostly caused by the clearance of crop residues, continuous crop harvest without sufficient fertilization, cation removal, and usage of acid-forming inorganic fertilizers. Acid soil reduces nutrient availability and produces Al and Mn toxicity. In addition to these effects, soil acidity may rapidly degrade soil physicochemical qualities such as organic carbon (OC), cation exchange capacity (CEC), soil structure, porosity, and texture. Liming, the use of organic materials as ISFM, and the adoption of crop types that are resistant to Al toxicity are all alternatives for correcting acid soils. Liming can minimize toxicity by lowering concentrations, improving the availability of plant nutrients like P, Ca, Mg, and K in the soil, and reducing heavy metal solubility and leaching. Application of organic matter has a liming impact because of its abundance in alkaline cations (such Ca, Mg, and K) that were released from OM during mineralization. The pH of the soil is raised by soil organic matter, which helps with soil acidity supplements.

Effects of Long-Term Fertilizer Managements on Soil Organic Carbon Mineralization Under the Double-Cropping Rice System in Southern China

ABSTRACT Soil organic carbon (SOC) plays an important role in maintaining or increasing soil fertility and quality in paddy field, but there is limited information about how SOC mineralization responds to different fertilizer managements under the double-cropping rice system in southern China. Therefore, this study was designed to explore changes in SOC content, soil enzyme activities, SOC mineralization at 0–10 cm and 10–20 cm layers, and its relationship with long-term fertilizer managements in a double-cropping rice system of southern China. The experiment included four fertilizer treatments: chemical fertilizer alone (CF), rice straw and chemical fertilizer (RS+F), 30% organic manure and 70% chemical fertilizer (OM+F), and without fertilizer input as a control (Con). These results showed that SOC and labile organic carbon contents at 0–10 cm and 10–20 cm layers in paddy field with RS+F and OM+F treatments were increased, compared to CF and Con treatments. Compared with Con treatment, SOC mineralization rate and accumulation with CF, RS+F, and OM+F treatments were increased. SOC accumulation and potential mineralization at 0–10 cm and 10–20 cm layers with RS+F and OM+F treatments were increased, compared with CF and Con treatments. SOC mineralization rate and accumulation at 0–10 cm layer with CF, RS+F, OM+F, and Con treatments were higher than that of 10–20 cm layer. These results indicated that soil invertase, cellulose and urease activities in paddy field with RS+F and OM+F treatments were significantly higher than that of CF and Con treatments. There was a significant positive relationship between SOC accumulation and SOC content, soil invertase, cellulose, urease activities but were significant negative correlated with soil pH, bulk density. As a result, these were beneficial practices for improving SOC content and SOC mineralization in a double-cropping rice field of southern China by combined application of rice residue or organic matter with chemical fertilizer managements.

Solvent effects on the ESIPT emission of salicylaldehyde Schiff base derivative: A theoretical reconsideration

Salicylaldehyde Schiff base derivatives have potential applications in bioimaging, chemical sensors and organic luminescence materials because of their high fluorescence quantum yield with the excited-state intramolecular proton transfer (ESIPT) process. Recently, Shu et al. studied the luminescent mechanism of the Et2N-substituted salicylaldehyde Schiff base compound (DDHAC) in solvents [Dyes and Pigments 195 (2021) 109708]. It showed double-peaked bands in an n-hexane solvent but a single-peaked band in an acetonitrile solvent. They suggested that the open-enol in the acetonitrile solvent was the dominant species. They considered that open-enol fluorescence and ESIPT fluorescence constituted a dual fluorescent phenomenon in the n-hexane solvent. However, because acetonitrile is a non-protonic solvent, DDHAC molecules in acetonitrile mainly existed as the lower-energy hydrogen-bonded enol form rather than the open-enol form alone. In addition, the open-enol did not undergo the ESIPT process in n-hexane. Therefore, the luminescence mechanism of the DDHAC molecules in n-hexane and acetonitrile solvents needs to be reconsidered. In this study, we investigated the DDHAC molecules in n-hexane and acetonitrile solvents using the density functional theory and time-dependent density functional theory. The potential energy surfaces and optimisation of structures elucidated that the DDHAC molecules in n-hexane and acetonitrile solvents underwent the ESIPT process. The calculated fluorescence peaks demonstrated that the single-peaked broad emission band in the acetonitrile solvent was formed by the combination of the hydrogen-bonded enol* and keto* forms rather than open-enol*. Moreover, the dual fluorescence peaks in the n-hexane solvent were reattributed to the open-enol* form and hydrogen-bonded enol* form. The lack of keto* fluorescence in the n-hexane solvent was attributed to diminished charge coupling in comparison to the enol* form. Our results revise the mechanism of the DDHAC molecules in n-hexane and acetonitrile solvents, providing guidance for designing efficient organic fluorescence probes.

Improvement of Soil Pore Distribution and Soil Moisture Content using Organic Matter Addition Technology

Background: Coffee plants in Sumbermanjing Wetan are commonly cultivated on dry lands that rely solely on rainfall as the source of water input that eventually makes them susceptible to climate change. The deficiency of organic material and water availability for these plants poses a significant challenge for coffee farmers in Sumbermanjing Wetan. Therefore, a research was conducted to investigate the addition of various organic matter through biopore infiltration holes in coffee plantations with the following objectives: i) to analyze the impact of applying organic matter on the distribution of soil pores and ii) to examine the effect of organic matter application on soil moisture content. Methods: The research was carried out in the Smallholder Coffee Plantation of Argotirto Village, Sumbermanjing Wetan District, Malang Regency. A randomized block design was implemented with five treatment groups, which included the control (P1), two biopore holes + manure (P2), two biopore holes + compost (P3), two biopore holes + green manure (P4) and surface-applied manure (P5), each repeated three times. The observed variables included the percentage of soil organic matter, pore distribution, available water capacity and soil moisture content. Result: The findings indicated that addition of organic matter in biopore infiltration holes enhanced soil organic material content, where treatment P4 (two biopore holes + green manure) exhibiting the highest soil organic material values in the first and third months after the application. The application of organic matter increased soil porosity in all treatments, where treatment P4 (two biopore holes + green manure) showing the highest available water capacity. This suggests that the utilization of organic matter can improve soil aggregation, thus increasing porosity and available water capacity. Consistently, soil water content at a depth of 40-60 cm tended to increase in the third month following biopore infiltration holes application, indicating that the addition of organic matter through biopore infiltration holes can enhance soil moisture at subsoil.