Water Impurities Research Articles

Биотехнологический потенциал чешуи рыб Астраханской области

Recycling of secondary fish resources is an important task for the organization of efficient and environmentally friendly production, taking into account the principle of resource conservation. To develop a comprehensive technology for processing fish scales, an in-depth and complete study of its types, chemical composition and dimensional and mass characteristics is necessary. It has been established that the scales of the fish of the Astrakhan region are represented by two types: ganoid (in sturgeon) and elasmoid (in most commercial and pond fish). Elasmoid scales are divided into cycloid and ctenoid. The ctenoid scales (in walleye, perch and pike) have outgrowths, which give it a roughness. Such scales are usually smaller than cycloid scales. The average size of the scales of fish in the Astrakhan region varies from 6.7 to 20.5 mm, the largest size is noted in white amur (20.5 mm), carp (18.9 mm) and carp (18.8 mm), the smallest in walleye (6.7 mm) and perch (7.1 mm). The average thickness of the scales varies from 79 microns (silver carp) to 942 microns (sturgeon). The mass yield of scales from whole fish ranges from 0.4% (sturgeon) and from 2.4 to 8.0% in representatives of the elasmoid type. The content of nitrogen-containing substances in the scales of the studied fish varies from 43.2% in perch to 68.7% in carp, the alkali-soluble protein fraction was found from 16.7% (sturgeon) to 58.4% (silver carp). In addition to the target component, impurities of water- and salt-soluble proteins, minerals and various pigments (chromatophores) were found in the scales, which must be separated in the technological process. As a result of the research, the classification of fish scales of the Astrakhan region by chemical composition has been compiled, taking into account the prospects for protein extraction. These studies are fundamental for creating integrated technological solutions for processing fish scales to obtain a wide range of food and feed products.

Revolutionizing material science: Enhanced functionalities through reduced graphene oxide/Al2O3/CuO/TiO2 nanocomposites

Reduced graphene oxide@Al2O3-CuO-TiO2 (ACT) based nanocomposites (NCs) were combined by regulated hydrothermal technique to create novel rGO@metal oxides-based NCs. The resultant NCs showed excellent photocatalytic, antibacterial, anticorrosive, and magnetic characteristics. The use of FTIR, TEM, UV-visible, X-ray diffraction, and SEM aids the structural examination of NCs. The synergistic pairing of ACT NPs with rGO exhibits enhanced photocatalytic, magnetic, anticorrosive, and antibacterial characteristics. The NCs exhibited paramagnetic character (χ = 0.140) and increased induced current with applied magnetic field. The photocatalytic properties of NCs were examined for decomposing methylene blue dye in UV and Sunlight. 94.7 % and 70.5 % dye degradation was observed under UV and Sunlight after 335 and 110 min. of exposure, respectively. The Zone of Inhibition was examined against S. aureus (Gram-positive) and E. coli (Gram-negative) bacteria and was found comparable with standard antibiotics (Ampicillin) against S. aureus bacterial strain. The NCs show 99 % corrosion inhibition efficiency at a low concentration (10 ppm). The potential applications of ACT@rGO NCs in environmental rehabilitation, the medical field, anticorrosive coatings, and impure water purification, contribute toward the development of advanced nanomaterials-based devices.

On the transition to the use of modern lubricants in systems of energy facilities

The analysis of turbine oils currently in use is given. The classifications for petroleum base oils according to the systems developed at JSC VNIINP and the American Petroleum Institute are presented. The transition from the operation of turbine oils of the first group to more advanced oils obtained on the basis of base oils of the second group and above is justified. The problems that may arise when replacing oils of the first group with modern oils in connection with the processes of mixing energy oils of various formulations are outlined. The mixing process is complicated by the compatibility factors of both the commercial products themselves and the additive compositions used, as well as possible contamination with oil sludge of lubricants in operation and possible contamination with water and mechanical impurities of the new energy oil at the delivery stage. The necessity of analyzing the possibility of mixing is explained both by the compatibility of the energy oils being tested and by the compatibility of the additive package used in them. A list of indicators is presented by which it is possible to judge the possible compatibility of the energy oils under consideration. The results of the compatibility analysis are presented. In modern foreign policy conditions, for the Russian Federation, there is a need to activate Russian developments and provide modern lubricants for a new generation of energy facilities. A possible solution to this issue, developed by the specialists of the NRU MPEI, is presented. A system for the production of oil distillate with subsequent production of base (group III) and commercial oil for high-ash initial coals of the brown coal and early black coal stages of coalification of coal basins closed for development is presented.

Effect of modifiers on the stability of 1‑butyl‑3-methylimidazolium-based ionic liquids

The distinctive capabilities of 1‑butyl‑3-methylimidazolium (bmim) cation-based ionic liquids (ILs) to dissolve lignocellulosic biomass offer the potential for the development of novel green bioprocessing technologies based on their utilization as green solvents. The limited range of thermal stability of ILs necessitates the use of various co-solvents to maintain solubility. In the present study, an original approach to determine the degree of degradation of alkylimidazolium ILs was proposed, based on the application of gravimetric analysis method to determine the content of volatile degradation products and high-performance liquid chromatography-high-resolution mass spectrometry (HPLCHRMS) to determine the total degree of degradation. The proposed approach, as well as the combination of HPLCHRMS with gas chromatography-mass spectrometry (GC–MS), was employed to comprehensively characterize the impact of additives and impurities (water, dimethyl sulfoxide, hydrochloric and acetic acids, diethylamine) on the degradation of bmim acetate, chloride, and methyl sulfate during thermal treatment under typical biomass dissolution conditions (150 °C, 24 h). The presence of additives or impurities in the composition of ILs has been found to predominantly contribute to a decrease in the number of volatile compounds formed, while increasing the variety and relative content of non-volatile degradation products. The use of protic solvents and acids results in a decrease in the overall degree of degradation of ionic liquids and in the fraction of volatile compounds formed. This allows for the classification of binary mixtures based on these additives as "green" solvents at temperatures below 150 °C.

Cobalt single-site molecular Catalyst-mediated electrochemical Hydrodechlorination for detoxification of halogenated Antibiotics: Performance, reaction pathway and mechanism

Electrocatalytic hydrodehalogenation (ECHD) offers a promising approach for detoxification of the halogenated antibiotics via hydrogenolysis of the C-X bonds (X = F, Cl or Br). Herein we demonstrated that the commercially-available cobalt phthalocyanine (CoPc) molecules with a high-loading of −[Co-N4]- moieties (Co wt%: 10.8 %) were exceptionally active for hydrogenolysis of the C-Cl bonds in florfenicol (FLO). It afforded an impressive mass activity of 6.2 gFLO h−1 g-1Co, a low Co leaching of 0.34 μg/L and a strong tolerance to interference from impurities in water, significantly surpassing reported Co/Fe/Ni-based particle and single-site counterparts. Mechanistic studies revealed that the ECHD on CoPc underwent a direct electron transfer manner rather than the atomic hydrogen (H*)-mediated indirect way, and the ECHD efficacy was affected by both the electron and proton transfer kinetics. The single-atom Co, with its d orbitals constituting the lowest unoccupied molecular orbitals of CoPc, served as the primary active site. It facilitated both electron and proton transfer, as well as the cleavage of the C-Cl bond but not the C-F bond. In a continuous-flow cell, the CoPc/C-driven ECHD reduced the antibacterial activity of a FLO-contaminated natural lake water sample by 90.8 % with an energy consumption of 0.19 kwh g-1FLO. This study highlighted great promise of the single-atom metal-bearing molecular catalyst toward the sustainable detoxification of halogenated antibiotics-contaminated water.

Impact of the surface on He(23S1) and He2(a3Σu+) metastables densities in atmospheric pressure RF plasma

Abstract The dynamic of helium metastable formation along an atmospheric pressure helium plasma channel with different bounding surfaces is analysed. The densities of He(23S1) and He2(a3Σu +) are measured using optical absorption spectroscopy. A simple model for helium metastable creation, quenching by water impurities and destruction upon surface impact, is developed. The model shows a very good agreement if one assumes that surfaces mainly control secondary electron emission, affecting the local heating at the plasma boundary sheath. This, in turn, changes the rate for He(23S1) and He2(a3Σu +) conversion. The helium metastable induced desorption of adsorbed water causes a decay of the metastable density along the plasma channel due to quenching.

Sustainable nanoparticles of Non-Zero-valent iron (nZVI) production from various biological wastes

Given the growing importance of biological wastes (such as leaves from pomegranate, green tea, oak, lemon, orange, peach, kiwi, and neem) based iron nanoparticles over the past ten years and their applications in the environment, it is important to investigate new methods for nanoparticle production. Significant research has been conducted in this field as synthesizing these materials now requires careful consideration of green chemistry principles, minimization of disposal, cleaner solvents, energy efficiency, and caring precursor ingredients. The goal of this work is to evaluate the characteristics of environmentally friendly, sustainable non-zero-valent Iron (nZVI) nanoparticle productionfrom different tree’s’ leaves. The requirements required for a product for environmental cleanup were taken into consideration when examining size, form, reactivity, and aggregation propensity. Three categories can be formed from the results of extracts in terms of antioxidant measurements (reported concentration of Fe (II)): >60 mmol/L, 20 mmol/L to 40 mmol/L, and 2 mmol/L to 5 mmol/L. Neem, oak, and green tea leaves yield the highest effects when compared to other tree leaves. It is possible to inject a different emulsion into the contaminated zone that contains nZVI, vegetable oil, and water. The best leaf extracts and operating conditions for generating sustainable nanoparticles from the bio-wastes of plant leaves must be chosen in order to use green nZVIs in environmental cleanup. These environmentally friendly nZVI nanoparticles can be used to treat impure waters to get rid of heavy metals and can useas an emulsion for paints.

Leveraging multi-omics tools to comprehend responses and tolerance mechanisms of heavy metals in crop plants.

Extreme anthropogenic activities and current farming techniques exacerbate the effects of water and soil impurity by hazardous heavy metals (HMs), severely reducing agricultural output and threatening food safety. In the upcoming years, plants that undergo exposure to HM might cause a considerable decline in the development as well as production. Hence, plants have developed sophisticated defensive systems to evade or withstand the harmful consequences of HM. These mechanisms comprise the uptake as well as storage of HMs in organelles, their immobilization via chemical formation by organic chelates, and their removal using many ion channels, transporters, signaling networks, and TFs, amid other approaches. Among various cutting-edge methodologies, omics, most notably genomics, transcriptomics, proteomics, metabolomics, miRNAomics, phenomics, and epigenomics have become game-changing approaches, revealing information about the genes, proteins, critical metabolites as well as microRNAs that govern HM responses and resistance systems. With the help of integrated omics approaches, we will be able to fully understand the molecular processes behind plant defense, enabling the development of more effective crop protection techniques in the face of climate change. Therefore, this review comprehensively presented omics advancements that will allow resilient and sustainable crop plants to flourish in areas contaminated with HMs.

Stability of hydrous basaltic melts at low water fugacity: evidence for widespread melting at the lithosphere-asthenosphere boundary

The upper mantle low velocity zone is often attributed to partial melting at the lithosphere-asthenosphere boundary. This implies that basaltic melts may be stable along plausible geotherms due to the freezing point depression in the presence of water and other incompatible impurities. However, the freezing point depression (ΔT) as a function of water content in the near-solidus basaltic melt (cH2O) cannot be precisely determined from peridotite melting experiments because of difficulties in recovering homogeneous basaltic glasses at high pressures. We therefore used an alternative approach to reinvestigate and accurately constrain the ΔT–cH2O relationship for basaltic melts at the low water fugacities that are expected in the upper mantle. Internally heated pressure vessel (IHPV) experiments were performed at water-saturated conditions in the anorthite-diopside-H2O system at confining pressures of 0.02 to 0.2 GPa and temperatures between 940 and 1450 ℃. We determined the water-saturated solidus, and obtained ΔT by combining our data with reports of dry melting temperatures in the anorthite-diopside system. In another series of experiments, we measured water solubility in haplobasaltic melts and extrapolated cH2O to pressures and temperatures of the water-saturated solidus. By combining the results from these two series of experiments, we showed that the effect of water on ΔT was previously underestimated by at least 50 ℃. The new ΔT–cH2O relationship was then used to revise predictions of melt distribution in the upper mantle. Hydrous melt is almost certainly stable beneath extensive regions of the oceanic lithosphere, and may be present in younger and water-enriched zones of the subcontinental mantle.

Impregnate Carbonation: CO2-Guided In Situ Growth of Robust Superhydrophobic Structures on Concrete Surfaces.

Superhydrophobic surfaces applying on concrete can greatly improve the durability of concrete by preventing the damage from water. However, traditional design of superhydrophobic concrete surfaces by external coating encounters to problems of flaking and poor surface robustness, while that by adding hydrophobic agents or particles faces the challenges of strength damage of concrete. Drawing inspiration from the carbonation phenomenon of concrete, here a new design of in situ growing superhydrophobic structures on concrete is proposed: The concrete sample is impregnated into Mg2+-containing silane-water system with continuous CO2 injection. The contact angle of the concrete surface achieves 171.9° without obvious strength decrease after 120 min, which are mainly attributed to the formation of CaxMg1-xCO3 crystals with micro-nano-structures and the reduction of carbonates surface energy by silane. This superhydrophobic concrete structure can be divided into a superhydrophobic-hydrophobic-hydrophilic three layers structure, providing the stable water-proof protection under mechanical fatigue, capillary water absorption, UV aging, sulfate attack, and impurity water impact tests due to the in situ growing robust superhydrophobic structures. Furthermore, it captures 29.80gm-2 CO2 during the reaction process, providing new insights for the design and preparation of eco-friendly superhydrophobic concrete.

Investigation of the insoluble impurities' impact on flow boiling heat transfer in aluminum microchannel heat exchangers

Microchannel flat-tube heat exchangers are known for their high heat transfer efficiency and compact size. In practical applications, the predominantly adverse influence of insoluble impurities on the condensation process necessitates further exploration into the underlying mechanisms affecting the flow boiling process. The effect of common insoluble impurities on the flow boiling of R410A refrigerant in a microchannel flat-tube heat exchanger has been investigated, and variation of the impurity volume fraction on heat transfer, mass transfer, pressure drop, and bubble formation are analyzed. Additionally, an adaptive modification method for the mass transfer factor is proposed. The numerical model of flow boiling heat transfer in a microchannel is validated through experimental data and empirical correlations. Thermo-hydraulic performance evaluation incorporates efficiency index and area goodness ratio metrics. Results reveal that the presence of insoluble impurities complicates the boiling heat transfer mechanism by influencing bubble evolution and multiphase flow patterns. Air impurities at a volume fraction not exceeding 5% prove beneficial for enhancing flow boiling efficiency in microchannels; however, a 38.5% decrease in efficiency index is observed with 1% oil impurities present. Optimal thermo-hydraulic performance is achieved with approximately 2%–3% water impurities.

SEARCH FOR METHODS TO INCREASE THE SEDIMENTATION RATE OF THE UPPER FLOATING LAYER OF OIL SLUDGE PITS

Traditionally, oil sludge with a liquid-viscous consistency is separated into petroleum product, water and solid mechanical impurities. A large number of technological devices, including separators, centrifuges, hydrocyclones of various designs, have been developed to carry out the operation of interfacial separation of liquid-viscous oil sludge.On the territory of every oil refinery that has been in operation for decades, there are oil sludge ponds — natural settling ponds in which large quantities of oil waste accumulate.The problem of processing barn oil sludge in the oil production and refining industry has not yet been completely solved. This is due to the high stability of barn emulsions, the peculiarities of their composition and properties, which are constantly changing under the influence of temperature and various processes occurring in them.The article presents the results of research aimed at identifying the possibility of destruction of a persistent oil-water emulsion taken from the upper floating layer of an oil sludge pit and its preparation without changing the technological scheme and technological parameters.The results of laboratory studies on the destruction of oily liquid during static sedimentation are considered. Simulation of the oily liquid preparation process was carried out in compliance with the temperature and time conditions of operation, with the use of demulsifiers, by analogy with the process of oily liquid preparation, as at the unit. The results of the simulation showed that at the dosage of the demulsifiers used at the unit, even with an increase in the dosage and an increase in the settling time to 5 days, the oil-water emulsion did not collapse at 60 0C. Further studies were carried out by testing eight brands of demulsifiers at different dosages and elevated temperatures. Based on the results of the research and the conclusions made, a scheme for the preparation of oil-containing liquid at static sludge with the existing set of equipment at the unit is proposed.Further studies were carried out to increase the depth and sedimentation rate of the persistent oil-water emulsion.

Synthesis of blue-sparkling N, S-doped carbon dots for effective detection of nitro explosive and Fe3+ ion and anti-counterfeiting studies

Highly blue-luminescent nitrogen & sulfur-doped carbon dots (N, S-CDs) made with homocysteine and ethylene diamine by simple single-step microwave-assisted style. The prepared carbon dots showed a higher photoluminescent quantum yield (PL-QY), which is found to be 45 %. FTIR and XPS analysis reveals that these N, S-CDs contain rich nitrogen, and sulfur as well as C=O and C=C functional groups. N, S-CDs had a mean size around 3-4 nm, very interestingly, obtained carbon dots exhibit excitation-dependent photoluminescent character, are water-soluble, and restore luminescent stability under UV-light exposure and a wide range of pH. The crafted N, S-CDs are hired for precise and discriminating detection of multiple water impurities such as Fe3+ ion and Picric acid. The complexation between oxygen species of N, S doped CDs, and Fe3+ ion follows the inner-filteration effect (IFE) and with Picric acid follows Forster Resonance Energy Transfer (FRET) for the doped N, S-CDs are found to be the utmost possible mechanism for the observed sensing performance. The lower detection limit (LOD) of Fe3+ sensors is about 0.11 µM and for picric acid is 0.07 µM. Moreover, these blue-emissive N, S-CDs as competent fluorescence sensors, have been used as fluorescent inks, as well as in advanced portable devices information security and filter paper-based probes for visual recognition might also hold prominent ability to make wider applications in biological systems.

Fabrication of Z-scheme Fe2O3/g-C3N4 nanocomposite with improved visible light induced photodegradation of pharmaceutical pollutants and photoelectrochemical water oxidation

The photodegradation and photoelectrochemical performance of Fe2O3 catalyst is an encouraging visible-light induced catalyst owing to its less harmfulness, cheap and ecofriendly. However, owing to its quick charge carriers recombination rate and less lifespan of charge carriers obstructs its catalyst application. Therefore, it has been lately established that the construction of heterojunction with other semiconductor might be a possible method to improve its catalytic activity. Herein, a novel Z-scheme Fe2O3/g-C3N4 heterostructure catalyst has been synthesized by a simple hydrothermal technique and studied its photoelectrochemical and photodegradation activity. The addition of g-C3N4 greatly improves the light absorption ability light, reduced charge recombination rate and progress the charge transportation. The composite catalyst exhibited the superior photodegradation performance (97.8 %) of sulfamethoxazole antibiotic remedy within 30 min of visible light illumination. •OH and •O2– radicals show a key role for dye degradation activity, and proposed a possible photodegradation charge carrier transfer mechanism based on a potential band structures of composite catalyst. Furthermore, the prepared catalysts are further used to examine the photoelectrochemical properties for hydrogen generation. The Fe2O3/g-C3N4 nanocomposite photoelectrode exhibited enriched photocurrent density (0.764 mA/cm2) than g-C3N4 (0.271 mA/cm2) and Fe2O3 (0.370 mA/cm2) photoelectrodes, which ∼ 2.8 and ∼2.1 folds greater photocurrent density than pure photoelectrodes. Electrochemical impedance spectroscopy analysis revealed that the composite electrode has minimal charge transfer resistance and greater electron transfer ability. Therefore, the current study presents a facile formation of Z-scheme catalyst and offers a sustainable method to eradicate water impurities and hydrogen generation by renewable solar energy.

Investigating Corrosion Degradation of Porous Transport Layers for PEM Water Electrolyzers Using on-Line ICP-MS

The degradation of polymer electrolyte membrane water electrolyzer (PEMWE) is the net result of degradation phenomena across each component, which includes structural changes to the catalyst layer, deactivation of the electrolyte, loss of performance due to impurities in the feed water, and the corrosion and passivation of titanium-based bipolar plates (BPPs) and porous transport layers (PTLs).1, 2 This presentation will focus on PTL degradation, which has received relatively little attention compared to loss of performance related to catalyst and electrode degradation mechanisms. Generally, PTL degradation can be categorized into chemical/corrosion degradation and mechanical degradation. 3 In this work, we focus on corrosion degradation of the anode PTL. Titanium (Ti) is the state-of-the-art material for PTLs due to its stability and intrinsic electrical conductivity. Ti can however, develop an oxide layer in the harsh oxidizing conditions of the anode, thus reducing the effective electrical conductivity and cell performance. Coating the Ti parts with platinum group metals (Pt or Ir) is often used to protect against oxidation.4 An electrochemical flow cell system connected to an inductively-coupled plasma-mass spectrometer (ICP-MS) capable of detecting trace concentrations (<ppb) of dissolved elements in solution has been used to investigate the corrosion rates of the Ti-PTLs with and without coatings toward understanding factors influencing degradation mechanisms. The influence of various parameters such as potential, potentiodynamic profile parameters (e.g., scan rate, upper and lower potential limits), electrolyte type, and pH on the corrosion processes has been investigated. References Feng, X. Yuan, G. Liu, B. Wei, Z. Zhang, H. Li, H. Wang, J. Power Sources 2017, 366, 33.Babic, M. Suermann, F. N. Büchi, L. Gubler, T. J. Schmidt, J. Electrochem. Soc. 2017, 164, F387.Park, H. Oh, T. Ha, Y.I. Lee, K. Min, Appl. Energy 155 (2015) 866-880.Rakousky, U. Reimer, K. Wippermann, M. Carmo, W. Lueke, D. Stolten, J. Power Sources 326 (2016) 120–128. Acknowledgements This research is supported by the U.S. Department of Energy, Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office under the auspices of the H2NEW consortium. Argonne National Laboratory is managed for the U.S Department of Energy by the University of Chicago Argonne, LLC under contract DE-AC-02-06CH11357.

Fabrication of Bipolar Membrane Electrolyzers for Seawater Electrolysis: Proof-of-Concept, Operando Design, and Fundamental Studies

Hydrogen (H2) is a critical industrial feedstock, essential in the production of fertilizer, steel, and fuels. Its demand is anticipated to increase ten-fold by 2050 due to its pivotal role in various new green technologies. Renewable energy-driven bipolar membrane water electrolyzers (BPMWEs) are a promising technology for sustainable production of H2 from seawater and other impure water sources. Here we present a detailed protocol on the assembly and operation of zero-gap membrane electrode assembly (MEA) BPMWE with water dissociation layers1. We describe steps for spray coating both electrodes and membranes, electrolyzer assembly, and electrochemical evaluation. This protocol provides an avenue to highlight key considerations in BPMWE fabrication methodology to ensure comparable data and rapid progress. We further highlight how this BPM platform can be used for a variety of scientific applications ranging from the seawater resistant BPMWE to an operando water electrolyzers to examine catalyst dynamics through X-ray absorption spectroscopy (XAS). As we work together towards a cleaner future, the detailed BPMWE protocol enables scientific communication, aiding in reproducible electrolyzer assembly practices, and accelerating the optimization of next-generation BPM-based devices.

Aqueous alternating electrolysis prolongs electrode lifespans under harsh operation conditions

It is vital to explore effective ways for prolonging electrode lifespans under harsh electrolysis conditions, such as high current densities, acid environment, and impure water source. Here we report alternating electrolysis approaches that realize promptly and regularly repair/maintenance and concurrent bubble evolution. Electrode lifespans are improved by co-action of Fe group elemental ions and alkali metal cations, especially a unique Co2+-Na+ combo. A commercial Ni foam sustains ampere-level current densities alternatingly during continuous electrolysis for 93.8 h in an acidic solution, whereas such a Ni foam is completely dissolved in ~2 h for conventional electrolysis conditions. The work not only explores an alternating electrolysis-based system, alkali metal cation-based catalytic systems, and alkali metal cation-based electrodeposition techniques, and beyond, but demonstrates the possibility of prolonged electrolysis by repeated deposition-dissolution processes. With enough adjustable experimental variables, the upper improvement limit in the electrode lifespan would be high.

Biomass-derived multiatom-doped carbon dots for water sensing based on excited state intraparticle proton transfer in organic solvents

The presence of trace water impurities in organic solvents can significantly influence chemical reactions and product quality; thus, the accurate detection of water content in these solvents is a critical requirement for industrial applications. Accordingly, an eco-friendly, effective, and economical sensor for detecting trace quantities of miscible water in organic solvents is required for industrial applications. In this study, we synthesized biomass-derived multi-atom-doped carbon dots (MACDs) as fluorescent probes and employed them for the detection of trace amounts of water impurities in several water-miscible organic solvents. The MACDs exhibited stable dual-color fluorescence emission under ultraviolet light irradiation and red and blue emissions in organic solvents and water. The fluorescence quantum yield was approximately 11 %, which indicates an excited intraparticle proton transfer response due to an increase in the water content within a wide response range from 0 % to 100 % (v/v) in organic solvents. The intensity of the red emission signal at 670 nm gradually decreased with an increase in the water content in the organic solvent. The MACDs could detect water with an instant response time of 55 s, a high sensitivity, and low limits of detection of 0.08 %, 1.36 %, 0.03 %, 0.04 %, 0.12 %, and 0.05 % (v/v) in ethanol, acetonitrile, dimethylformamide, methanol, isopropanol, and tetrahydrofuran, respectively. Hence, biomass-derived MACDs can serve as efficient and eco-friendly water sensors in organic solvents.

Interfacial engineering dominated passivation strategy to facilitate performance improvement of CsSnCl3 PSCs by induced Sn–O bonds: Insight from DFT calculations and device simulations

Defect passivation of perovskite surface not only reduces non-radiative recombination due to defect trapping charge, but also modulates the interfacial structure and energy levels, making it an effective means of solving the stability problem of perovskite materials. This work provides a passivation strategy for CsSnCl3 perovskite, and the interfacial interactions between CsSnCl3 and the passivation agent (PbSO4 and PbCO3) are explored based on first-principles density functional theory. By introducing PbSO4 and PbCO3 with multifunctional quantum dots, strong Sn-O bonds are formed with unsaturated coordination and dangling bonds on the surface of CsSnCl3. Binding sites of water molecules and impurities would be occupied by these bonds, to achieve surface passivation and dehumidification effects, and significantly improve the optical properties of CsSnCl3. PbCO3/SnCl and PbSO4/SnCl constructed the satisfactory interfacial energy level structures. PbCO3/SnCl exhibited excellent light absorption performance ranging in 0 ∼ 1200 nm. Introducing PbSO4 and PbCO3 reduced the refractive index of CsSnCl3 exhibiting excellent extinction properties. According to the simulation of Solar Design, perovskite solar cells (PSCs) constructed by (PbSO4, PbCO3)/CsSnCl3 as the active layer achieved power conversion efficiencies of 15.1946 % and 17.3783 %, respectively. This work’s research and design results provide a passivation strategy and PSCs design scheme for CsSnCl3 surface defects, which is of great significance for further modification of CsSnCl3 to better apply in photovoltaic field.

Densities, Viscosities, and Self-Diffusion Coefficients of Octan-1-ol and Related Ether-Alcohols.

Density, viscosity, and self-diffusion coefficients are reported for octan-1-ol and the related ether-alcohols 2-pentoxy-ethan-1-ol, 3-butoxypropan-1-ol, 4-propoxybutan-1-ol, 5-ethoxypentan-1-ol, and 6-methoxyhexan-1-ol covering temperature ranges from 298.15 to 359.15 K. These new data reveal structure-property relationships affected by the presence and the position of the ether moiety in the molecular structure of the ether-alcohols. Compared to octan-1-ol, the presence of the ether moiety causes an increase in intermolecular hydrogen bonding interactions, resulting in higher densities. The increase in density is less pronounced for those ether-octanols that engage in intramolecular hydrogen bonding. As for the effects of the ether moiety on the dynamics, these are generally faster for the ether-alcohols compared to octan-1-ol, suggesting that hydrogen bonding between ether oxygen and hydroxy hydrogen is weaker compared to hydrogen bonding between two hydroxy groups. The activation energies obtained from an Arrhenius analysis are higher for translational motion than for momentum transfer for all alcohols. There are additional finer details across the ether alcohols for these activation barriers. These differences cancel out for the mathematical product of self-diffusion coefficient and viscosity (Dη). The effect of water impurities on the studied properties was also investigated and found to lead to small increases in densities for all alcohols. Viscosities decrease for octan-1-ol and 2-pentoxyethan-1-ol but increase for the other ether-alcohols that can engage in intramolecular hydrogen bonding.