Mixture Of Oxides Research Articles

The inhibition effects of chlorogenic acid on the formation of colored oxidation products of (-)-epigallocatechin gallate under enzymatic oxidation.

Untargeted Liquid chromatography tandem mass spectrometry (LC-MS) based metabolomics in combination with UV-visible and colorimeter was applied in identifying critical colored enzymatically oxidized products of (-)-epigallocatechin gallate (EGCG). Pearson correlation coefficient analysis between marker compounds and a* value was conducted, and then a series of colored oxidation products were targeted and subsequently identified by diode array detection and mass fragmentation ions. The quinone of oolongtheanin 3-O'-gallate degraded product with quasi-molecular mass ion at m/z 711 was identified as a critical colored oxidation product of single EGCG. To explore the effect of chlorogenic acid on the formation of colored EGCG enzymatic oxidation products, the variation of oxidation products on the oolongtheanin pathway was semi-quantitatively determined. The result showed chlorogenic acid significantly inhibited the formation of colored oxidation products, thus lightened the color of EGCG oxidation mixture. The addition of chlorogenic acid influences the process of tea polyphenols' enzymatic oxidation.

Synthesis of nanopowders by the glycine-nitrate method in the In-Dy-O system

We investigated the feasibility of synthesizing nanopowders containing indium and dysprosium oxides by the glycine-nitrate method. It was found that the glycine-nitrate method significantly reduces the content of the indium component in the resulting mixture of indium and dysprosium oxides. In this case, intensive absorption of carbon dioxide from the air by the formed particles induces formation of amorphous carbonaceous compounds, which decompose only under high-temperature treatment (900 °C). This prevents compaction of powders synthesized by the glycine-nitrate method. Comparison of the characteristics of powders containing indium oxides and dysprosium, synthesized by the glycine-nitrate method and by the method of co-precipitation of indium and dysprosium hydroxides from chloride solutions, showed the advantage of the co-precipitation method in the pressing of powders.

Explosion behaviors of hydrogen-nitrous oxide mixtures with propane addition

In the present work, the explosion of hydrogen-propane-nitrous oxide mixtures with various equivalence ratios (ϕ=0.2-2.4), propane fractions (ωC=0-1.0) and initial pressures (P0=50-100 kPa) at ambient temperature (288 K, room temperature) was experimentally performed in a standard 3.375-L cubic vessel. The maximum explosion pressure (Pmax), maximum pressure rise rate ((dp/dt)max) and explosion time (te) were obtained in light of pressure–time curves, and the normalized maximum explosion pressure (Pmax/P0) and normalized explosion time (td/te) were analyzed as well. Moreover, the adiabatic pressure (Pad) and laminar burning velocity (SL) were also calculated for argumentation. The results indicate that with the increase of ωC, Pmax and (dp/dt)max both present three characteristic variation trends for different ϕ, while the inflections of Pmax-ϕ and (dp/dt)max-ϕ transient gradually from lean to rich mixtures. Besides, te and td/te are monotonously rising with ωC, illustrating that propane addition can remarkably decelerate the explosion process. In addition, with the increase of P0, Pmax/P0 raises monotonously and is asymptotic to Pad/P0 at ωC⩽0.2, demonstrating that heat loss decreases under higher P0. Linear dependence is also found between (dp/dt)max and P0 for any composition. Furthermore, te monotonically decreases with P0, due to the flame acceleration occurring in the combustion period. In general, the presence of nitrous oxide (N2O) with a large content makes the explosion extremely unstable, and a spot of propane can dramatically alter the explosion characteristics of H2-N2O mixtures. These results will be meaningful for the development of explosion-mitigation devices and technology in case of underlying explosion and fire hazards.

Experimental Evaluation and Design of Propulsion System For Cubesat: N2o and C2h4 as Green Bipropellant

This work proposes a design of a new propulsion module for a 3U CubeSat that will be used for collision avoidance and for deorbiting the spacecraft. We propose a bi-propellant, a mixture of Ethylene and Nitrous oxide which has no toxicity. The bi-propellant system used does not need an additional pressurizing system and will ignite automatically when the mixture will enter the combustion chamber. Due to these features, our propulsion module uses only 1U space of the CubeSat saving 2U for other systems. In this study, a program such as CEA and RPA were used for chemical equilibrium calculation developed in NASA and German Universities. It contains a thermodynamic data library, the PAC99 program which does regression and estimation of thermodynamics, numerical analysis data and chemical equilibrium analyzed by various stimulations. This propulsion evaluation aims at the calculation of efficiency, feasibility and specific impulse obtained was larger than 300 seconds.

Mechanical, gamma rays and neutron radiation transmission properties for some ZnO–TeO2–P2O5-ZnX glasses

Oxyhalide glasses are utilized in the process of immobilizing nuclear waste and function as scintillating agents for the purpose of radiation detection. The objective of this study is to examine the enhanced mechanical and radiation attenuation characteristics of newly developed oxyhalide glasses by incorporating zinc-iodide. This study investigates the synthesis process, mechanical properties, and experimental gamma-neutron radiation transmission properties. A halogen-free base glass, consisting of an oxide mixture of P2O5, TeO2, and ZnO, was synthesized. Following that, the initial glass composition was further strengthened by the addition of zinc bromide (ZnBr2), zinc chloride (ZnCl2), zinc fluoride (ZnF2), and zinc iodide (ZnI2) in a successive manner. The experimental configuration entailed positioning circular glass samples between a 133Ba radioisotope and a Canberra High Purity Germanium (HPGe) detector. The determination of attenuation coefficients is achieved through the measurement of individual attenuation properties. Afterwards, theoretical approaches are utilized to determine the mechanical characteristics of halogenated glasses, including Young's modulus (Y), Bulk modulus (K), Shear modulus (G), Longitudinal modulus (L), and Poisson's modulus (v). The results of the study suggest that the implementation of the halogenation process on the P2O5–TeO2–ZnO base composition led to a significant enhancement in the examined properties. The incorporation of zinc-iodide in the halogenation process resulted in a significant improvement in the gamma absorption properties. The utilization of zinc in the halogenation process demonstrates multifunctional capabilities, which involve the potential to enhance various glass properties, including durability and gamma-ray absorption properties. It can be concluded that zinc-iodide demonstrates enhanced halogenation capabilities in comparison to zinc bromide, zinc chloride, and zinc fluoride.

Role of cobalt chloride indicator in the methane dry reforming over inexpensive allochroic silica gel supported nickel catalysts

Reducing the catalyst cost by using inexpensive support material is essential to its scale-up application in methane dry reforming (MDR) process. Herein, we report an allochroic silica gel (ASG) supported nickel catalyst for MDR reaction, considering abundant SiO2 resources and its direct granular shape. A series of catalysts were prepared by a facile impregnation method and the role of the contained cobalt chloride indicator was particularly studied. Characterization results implied that the cobalt chloride indicator was transformed into a mixture of cobalt oxides (CoOx) after calcination. The activity tests showed that ASG supported catalyst (Ni/ASG) had lower CH4 and CO2 conversion than the Co-free catalyst supported on ordinary silica gel (Ni/OSG), which is caused by the decreased Ni dispersion after Co addition. Adding Co into Ni/OSG can cause surface aggregation of CoOx species, which is less uniform than Ni/ASG. On the contrary, the 30-h stability test showed that the absence of CoOx species is detrimental to the catalyst durability due to the heavy carbon deposition of Ni/OSG. The origin of coke formation is elucidated from reaction mechanism perspective via in-situ DRIFTS analysis, where both Co-containing and Co-free catalysts are similar in CH4 stepwise dissociation and CO2 breakage forming bridged carbonyls but diverge in the carbonate intermediates. The special existence of carbonate intermediates interfere the desorption process of bridged carbonyls meanwhile enhance the interaction between C radicals and Ni actives, which further accumulate into the substantial deposited carbon.

Anesthesia in the Korean War.

Relying on original, primary source documentation from the National Archives, we describe the practice of anesthesia in mobile army surgical hospital (MASH) units and the 171st Evacuation Hospital during the latter part of the Korean War in 1953. Values were scaled and reported as percentages. These Essential Technical Medical Data Sheets reveal a surprising proportion (12.9%) of men received spinal anesthetics, despite official recommendations to the contrary. Still, the majority (69.2%) of the wounded underwent general anesthesia, most commonly through a mixture of thiopental and nitrous oxide. Despite data from World War II demonstrating the advantages of endotracheal intubation in these patients, few patients (20.6%) were intubated. Six percent benefited from the new curare-based drugs. This is the first English-language article that describes the practice of anesthesia during the Korean War. Utilizing primary source documentation, we found that general anesthesia was the most common type utilized. Newer techniques were not as commonly adopted, despite official recommendations and data from the time. The care provided closely resembled that delivered in the Second World War but inspired a series of technological and pedagogical reforms through the 1950s to improve military anesthesia for the next conflict.

Giant magnetostriction in La2CoMnO6 synthesized by microwave irradiation

Polycrystalline insulating ferromagnetic double perovskite La2CoMnO6 possessing a monoclinic structure and a high Curie temperature (TC = 222 K) was rapidly synthesized (∼30 min) by irradiating a stoichiometric mixture of oxides with microwaves. The sample exhibits negative magnetostriction (λpar), i.e., contraction of length along the magnetic field direction in the ferromagnetic state. At 10 K, λpar does not show saturation up to a magnetic field of 50 kOe, where it reaches 610 × 10−6, which is one of the highest values of magnetostriction found so far among perovskite oxides with 3d ions. The magnitude of λpar decreases monotonically as the temperature increases and becomes negligible above TC. The giant magnetostriction in this double perovskite is suggested to originate from large spin–orbit coupling associated with Co2+ (d7) cation. The obtained magnetostriction value is comparable to λpar = 630 × 10−6 in an identical composition obtained through solid-state reaction over several days in a conventional furnace, which indicates the advantages of microwave-assisted synthesis in saving reaction time and electric power without deteriorating physical properties.

Phase Transformations upon Formation of Transparent Lithium Alumosilicate Glass-Ceramics Nucleated by Yttrium Niobates

Phase transformations in the lithium aluminosilicate glass nucleated by a mixture of yttrium and niobium oxides and doped with cobalt ions were studied for the development of multifunctional transparent glass-ceramics. Initial glass and glass-ceramics obtained by isothermal heat-treatments at 700–900 °C contain YNbO4 nanocrystals with the distorted tetragonal structure. In samples heated at 1000 °C and above, the monoclinic features are observed. High-temperature X-ray diffraction technique clarifies the mechanism of the monoclinic yttrium orthoniobate formation, which occurs not upon high-temperature heat-treatments above 900 °C but at cooling the glass-ceramics after such heat-treatments, when YNbO4 nanocrystals with tetragonal structure undergo the second-order transformation at ~550 °C. Lithium aluminosilicate solid solutions (ss) with β-quartz structure are the main crystalline phase of glass-ceramics prepared in the temperature range of 800–1000 °C. These structural transformations are confirmed by Raman spectroscopy and illustrated by SEM study. The absorption spectrum of the material changes only with crystallization of the β-quartz ss due to entering the Co2+ ions into this phase mainly in octahedral coordination, substituting for Li+ ions. At the crystallization temperature of 1000 °C, the Co2+ coordination in the β-quartz solid solutions changes to tetrahedral one. Transparent glass-ceramics have a thermal expansion coefficient of about 10 × 10−7 K−1.

Catalytic Biomass Gasification in Supercritical Water and Product Gas Upgrading

AbstractThe gasification of biomass with supercritical water, also known as SCWG, is a sustainable method of hydrogen production. The process produces a mixture of hydrogen, carbon oxides, and hydrocarbons. Upgrading this mixture through steam or dry reforming of hydrocarbons to create synthesis gas and then extra hydrogen is a viable way to increase hydrogen production from biomass. This literature review discusses combining these two processes and recent experimental work on catalytic SCWG of biomass and its model compounds and steam/dry reforming of produced hydrocarbons. It focuses on catalysts used in these processes and their key criteria, such as activity, selectivity towards hydrogen and methane, and ability to inhibit carbon formation and deposition. A new criterion is proposed to evaluate catalyst performance in biomass SCWG and the need for further upgrading via reforming, based on the ratio of hydrogen bound in hydrocarbons to total hydrogen produced during SCWG. The review concludes that most catalysts used in biomass SCWG trap a large proportion of hydrogen in hydrocarbons, necessitating further processing of the product stream.

Crystal structure, piezoelectric and magnetic properties of solid solutions BiMn1-xFexO3 (x ≤ 0.4)

Сrystal structure, piezoelectric and magnetic properties of solid solutions BiMn1-xFexO3 (x ≤ 0.4) prepared by solid-phase reactions from a stoichiometric mixture of simple oxides at high pressures and temperatures have been studied. The structure of the compounds is characterized by the concentration driven phase transition from the monoclinic structure to the orthorhombic structure at x ≈ 0.2; wherein the ordering dz2 of the orbitals of Mn3+ ions is destroyed, and the inhomogeneous magnetic state is stabilized. Solid solutions with 0.2 ≤ x ≤ 0.4 are characterized by a nonzero piezoelectric response, wherein both ferroelectric and magnetic domain structures exist, the ferroelectric switching voltage decreases with an increase of iron ions concentration, while the residual magnetization value decreases. The maximum value of the piezoresponse signal is observed in the compound BiMn0.7Fe0.3O3. The work clarifies the relationship between the chemical composition, the crystal structure, piezoelectric and magnetic properties of solid solutions BiMn1-xFexO3. The presence of both magnetic and electric dipole ordering indicates the perspectives for the practical usage of such materials.

MgO-mediated activation of active carbon as an affordable strategy to “in situ” degradation of lindane in contaminated soils

The accumulation in soil landfills of toxic and persistent lindane, widely used as an insecticide, triggers the risk of leaching with the concomitant contamination of surrounding rivers. Thus, viable remediation to eliminate in situ high concentrations of lindane in soil and water becomes an urgent demand. In this line, a simple and cost-effective composite is proposed, including the use of industrial wastes. It includes reductive and non-reductive base-catalyzed strategies to remove lindane in the media. A mixture of magnesium oxide (MgO) and activated carbon (AC) was selected for that purpose. The use of MgO provides a basic pH. In addition, the specific selected MgO forms double-layered hydroxides in water which permits the total adsorption of the main heavy metals in contaminated soils. AC provides adsorption microsites to hold the lindane and a reductive atmosphere that was increased when combined with the MgO. These properties trigger highly efficient remediation of the composite. It permits a complete elimination of lindane in the solution. In soils doped with lindane and heavy metals, it produces a rapid, complete, and stable elimination of lindane and immobilization of the metals. Finally, the composite tested in lindane-highly contaminated soils permits the “in situ” degradation of nearly 70% of the initial lindane. The proposed strategy opens a promising way to face this environmental issue with a simple, cost-effective composite to degrade lindane and fix heavy metals in contaminated soils.

Crystal structure, piezoelectric and magnetic properties of BiMn1-xFexO3 (x ≤ 0.4) solid solutions

The crystal structure, piezoelectric and magnetic properties of BiMn1-xFexO3 (x ≤ 0.4) solid solutions synthesized using different solid state reactions from a stoichiometric mixture of simple oxides at high pressures and temperatures have been studied. The structure of the composition undergoes a concentration phase transition from the monoclinic to the orthorhombic structure. The formation of the orthorhombic phase is observed at the concentration x ≈ 0.2 and is accompanied by the destruction of the dz2 orbitals of the Mn3+ ions causing the stabilization of a homogeneous magnetic state. The solid solutions containing 0.2 ≤ x ≤ 0.4 exhibit a non-zero piezoresponse and may have ferroelectric or magnetic domain structures, the ferroelectric switching voltage decreasing with an increase in the iron concentration while the remanent magnetization decreases. The highest piezoresponse signal is observed for the BiMn0.7Fe0.3O3 solid solution. The relationship between the chemical composition, type of crystal structure, piezoelectric and magnetic properties of the BiMn1-xFexO3 solid solutions has been verified. Due to the combination of magnetic and electric dipole ordering these materials show good promise for practical applications.

Facile synthesis of graphene oxide-supported CoOx nanoparticles for efficient degradation of antibiotics via percarbonate activation: Performance, degradation pathway and mechanism

Recently, sodium percarbonate (SPC) is widely applied as a potential alternative of liquid H2O2 for advanced oxidation processes in waste treatment. Compared with H2O2, SPC could be used in a wider pH range and acted as a buffer for neutralizing the acidity in Fenton oxidation. Herein, we synthesized the two-dimension graphene oxide-supported CoOx nanoparticles (CoOx/GO), via the stabilization of CoOx nanoparticles at the surface of graphene oxide (GO), in SPC activation for degrading tetracycline. The detailed characterizations have confirmed CoOx/GO nanohybrid exhibits a two-dimensional thin nanosheet structure, and CoOx, which is a mixture of cobalt oxides and cobalt hydroxides, are successfully immobilized onto the surface of GO. Compared with other carriers, CoOx/GO presents the superior catalytic activity, with 80% degradation efficiency and 37.86% mineralization rate, in TC degradation via SPC activation. These results have lighted the significant role of GO in CoOx/GO nanohybrid for TC degradation via SPC activation. It seems that the electrons were transferred from GO to Co atoms, and enriching the electron cloud density of Co atoms, which was favour of SPC activation. Free radical quenching tests and EPR results demonstrated that OH• and •CO3- were dominating reactive oxygen species in CoOx/GO/SPC system. This study not only proposes an efficient method for the synthesis of Co-based nanocatalysts, but also provides a high-efficiency catalytic system for TC degradation.

Synthesis of single‐phase high‐entropy diboride powders and their spheroidization process

AbstractSpherical (Zr.2Ti.2Ta.2Nb.2Mo.2)B2 powders with a uniform particle size distribution are successfully prepared using a novel industrial approach, which combines spray‐drying process and thermal plasma sintering technology together. In this, single‐phase (Zr.2Ti.2Ta.2Nb.2Mo.2)B2 powders are first synthesized via a borothermal reduction process using a mixture of individual metallic oxides and boron powders as starting materials. The influence of boron powder content on the structure of prepared powders is researched. Then, (Zr.2Ti.2Ta.2Nb.2Mo.2)B2 granules are prepared after wet‐grinding and spray‐drying process, which exhibit a spherical shape and homogeneous element distribution. RF induction thermal plasma is finally used to sinter the granulated particle, and the apparent density of sintered spherical powders is increased to 2.57 g/cm3 from 1.43 g/cm3. Such powders are in potential demand for additive manufacturing techniques, and the successful synthesis of spherical (Zr.2Ti.2Ta.2Nb.2Mo.2)B2 powders may guide the way toward the preparation of many other spherical high‐entropy diboride powders.

Synthesis and Properties of a Carbon Monoxide Oxidation Catalyst Based on Titanium Dioxide and Platinum Nanoparticles

Carbon monoxide oxidation catalysts comprising Pt clusters on titanium dioxide with an oxide particle size of 6 and 20 nm have been synthesized. The catalysts have been studied using TEM, XRD, and XPS techniques, and it has been found that platinum clusters coated with a mixture of platinum oxides are formed on the support surface. The coherent scattering region of the Pt cluster is close to 5–6 nm for the studied oxide supports. The catalytic properties in the CO oxidation reaction at 295 K and low CO concentrations(less than 100 mg/m3) have been examined. The catalyst based on titania with a particle size of 20 nm and a platinum loading of 10 wt % has been found to have the CO oxidation rate 100 times higher than that on platinum black with a specific surface area of 30 m2/g. The catalysts are promising for use in catalytic air purification systems.

Synthesis and Electronic Structure of Bimetallic AuFe Nanocomposites

Au, Fe, and AuFe nanoparticles were obtained by metal vapor synthesis using acetone as the dispersion medium. The composition and electronic structure of the particles were studied by TEM, SEM, XPS, XANES, and EXAFS. The Au and Fe particles with average diameters of 5.3 and 1.8 nm, respectively, were obtained. According to X-ray diagnostic methods, gold was in the main Au0 state, and the Au+ and Au3+ states are present in small amounts while iron existed as mixture of non-stoichiometric oxides with states close to Fe2+ and Fe3+. Bimetallic nanoparticles were solid solutions with a disordered structure and Au–Fe–O and Au–O–Fe bonds. A carbon-containing shell was detected for all types of metal particles. The obtained materials may be promising for the development of improved antimicrobial agents and new methods for treating cancer diseases.

Thermodynamic Analysis of a Composite Obtained Using a Mixture of Copper and Molybdenum Oxides and Sulphides

The purpose of the study is selecting the optimal composition of antifriction composites alloyed with refractory metal sulfides in copper-based systems and developing the design of a laboratory plant for the production of sinter by pyrolysis of coke chemistry production resins. The object of the study is antifriction composites based on rare metal sulfides and coke chemistry production resins. The methodology of the work is determined by the use of modern physical and chemical research methods and modern software systems. As a result of the studies, the probable chemical reactions between compounds of copper and rare metals: molybdenum, tungsten with and without the participation of carbon, have been compiled. The optimal compositions of antifriction composites based on copper and rare metal sulfides have been determined, and a laboratory plant has been designed for the production of sinter by pyrolysis of coke chemistry production resin. The scope of the results is materials science and technology of new materials. Based on the thermodynamic analysis of various reactions that are likely to occur during the preparation of the cladding carbon lubricant composition based on powdered copper and carbon with the addition of rare metal sulfides (MoS2), the most appropriate component composition of the charge has been selected. In this case, a reducing agent is used: soot obtained from resins of coke production that has an amorphous structure and does not have solid impurities. The main choice was made on the formation of metallic copper and disulfides of rare metals in the presence of active carbon. The most probable reaction is the formation of metallic copper and molybdenum disulfide in the presence of carbon. Carbon and copper are macro-components of the lubricant, and rare metal sulfides are additives that improve its plasticity. It is also important that carbon does not contain abrasive impurities and has certain hardness and fineness. These qualities are ensured in the production of black carbon using coke chemistry resins. To obtain black carbon, a laboratory plant has been designed that will be used for the pyrolysis of resin from the coke chemistry production.

The Use of Equimolar Mixtures of Nitrous Oxide and Oxygen in Oral Surgery-A Retrospective Study of Patients in a Swiss University Hospital Setting.

The purpose of the study was to evaluate the success of procedural conscious sedation using inhaled equimolar nitrous oxide-oxygen (NOIS-EMONO) in patients undergoing routine dental and oral surgery procedures in a Swiss university hospital setting. The authors conducted a retrospective cohort study of patients that underwent NOIS-supported procedures between 2018 and 2022 at the oral surgery department of the University Hospital of Geneva (HUG), Switzerland. The primary outcome was the measurement of the procedure's success and efficacy as defined by the European Society of Anesthesiology. Secondary objectives included the analysis of the types of treatments performed, their indications, patient behavior, and the patient-clinician satisfaction score. 55 patients were included in the study; 85% underwent surgical procedures, and the remaining 15% underwent restorative and preventive procedures. The overall treatment success rate was 98.2% and 97.9% for surgically treated patients. Out of the patients, 62% appeared relaxed, calm, and serene, while 16% expressed pain or fear during the procedure. Infiltrative administration of local anesthesia caused stress in 22% of patients. This portion was significantly lower in sub-cohorts who received local topical anesthetics (0%) or a combination of systemic and local topical analgesics (7%). Patients (75%) and clinicians (91%) were satisfied with the procedure. Inhaled equimolar nitrous oxide-oxygen procedural sedation used during dental procedures and oral surgery results in high treatment success and satisfaction rates. The administration of additional topical anesthetics helps to reduce the anxiety and stress related to infiltrative anesthesia. Further dedicated studies and prospective trials are needed to confirm these findings.

In vitro bioassays for monitoring drinking water quality of tap water, domestic filtration and bottled water

BackgroundLocation-specific patterns of regulated and non-regulated disinfection byproducts (DBPs) were detected in tap water samples of the Barcelona Metropolitan Area. However, it remains unclear if the detected DBPs together with undetected DPBs and organic micropollutants can lead to mixture effects in drinking water.ObjectiveTo evaluate the neurotoxicity, oxidative stress response and cytotoxicity of 42 tap water samples, 6 treated with activated carbon filters, 5 with reverse osmosis and 9 bottled waters. To compare the measured effects of the extracts with the mixture effects predicted from the detected concentrations and the relative effect potencies of the detected DBPs using the mixture model of concentration addition.MethodsMixtures of organic chemicals in water samples were enriched by solid phase extraction and tested for cytotoxicity and neurite outgrowth inhibition in the neuronal cell line SH-SY5Y and for cytotoxicity and oxidative stress response in the AREc32 assay.ResultsUnenriched water did not trigger neurotoxicity or cytotoxicity. After up to 500-fold enrichment, few extracts showed cytotoxicity. Disinfected water showed low neurotoxicity at 20- to 300-fold enrichment and oxidative stress response at 8- to 140-fold enrichment. Non-regulated non-volatile DBPs, particularly (brominated) haloacetonitriles dominated the predicted mixture effects of the detected chemicals and predicted effects agreed with the measured effects. By hierarchical clustering we identified strong geographical patterns in the types of DPBs and their association with effects. Activated carbon filters did not show a consistent reduction of effects but domestic reverse osmosis filters decreased the effect to that of bottled water.Impact statementBioassays are an important complement to chemical analysis of disinfection by-products (DBPs) in drinking water. Comparison of the measured oxidative stress response and mixture effects predicted from the detected chemicals and their relative effect potencies allowed the identification of the forcing agents for the mixture effects, which differed by location but were mainly non-regulated DBPs. This study demonstrates the relevance of non-regulated DBPs from a toxicological perspective. In vitro bioassays, in particular reporter gene assays for oxidative stress response that integrate different reactive toxicity pathways including genotoxicity, may therefore serve as sum parameters for drinking water quality assessment.