Oxidation Ratio Research Articles

Enhanced Production of Organosulfur Species during a Severe Winter Haze Episode in the Guanzhong Basin of Northwest China.

The molecular composition of organic aerosols in ambient PM2.5 was investigated in an urban area in the Guanzhong basin of northwest China during a severe regional haze episode in the winter of 2018/2019. Organic matter, accounting for 20-35% of PM2.5 mass concentration, was characterized using direct infusion and electrospray ionization coupled with high-resolution Orbitrap mass spectrometry. The number of organic molecular formula assignments was primarily dominated by organosulfur species (OrgS, including CHOS and CHONS) in negative ion mode. The number and peak signal intensity of OrgS distinctly increased during the severe haze episode. Organosulfates and nitrooxy-organosulfates constituted the majority number (72-94%) of OrgS over the entire period. Although the OrgS were mostly present in aliphatic molecular structures, an increase in the number of polycyclic aromatic OrgS on haze days revealed the enhanced contribution from anthropogenic sources. The number of OrgS strongly correlated with ambient relative humidity and the oxidation ratios of sulfur and nitrogen, suggesting the important roles of aqueous phase chemistry and atmospheric oxidation in the formation of OrgS. A thorough understanding of the significance of OrgS will be essential to assess and mitigate the adverse impacts of haze pollution.

Characterisation and Source Identification of Inorganic Water-Soluble Ions in PM2.5 in a Small-Size Steel City of China

Ambient PM2.5 samples were collected in Laiwu, a small industrial city in China known for steel production, to measure and evaluate the mass concentrations of PM2.5 and the inorganic water-soluble ions (IWS ions). The highest PM2.5 value recorded was 251.28 μg/m3, which occurred during winter and was lower than other major Chinese cities. The spatial distribution showed that the center of the city, which is connected to the downtown area, was heavily polluted (170 μg/m3 higher) compared to the suburbs. With the exception of winter, the weight of PM2.5 was dominated by IWS ions, with three secondary ions (NO3 -, SO4 2-, and NH4 +) accounting for more than 70% of the total ions in mass. This percentage is higher than that of big cities. An increase in sulfur oxidation ratios (SOR), nitrogen oxidation rate (NOR), and anion equivalent/cation equivalent (AE/CE) indicated that the atmosphere in Laiwu was more oxidized than other big cities. The ion analysis revealed that PM2.5 was highly correlated with NO3 -, SO4 2-, and NH4 +. The principal component analysis indicated that district heating during winter and industrial output and secondary transformation during summer were the major sources of the water-soluble ions. The backward trajectory study identified the north of Shandong Province as the likely source-area that affected air quality in Laiwu.

Integrated Biphasic Electrochemical Oxidation of Hydroxymethylfurfural to 2,5-Furandicarboxylic Acid

Production of biobased platform chemicals and polymers via electrochemical routes enables the direct utilization of electrical energy from renewable sources. To date, the integration of electrochemical conversions in process chains remains largely unexplored, and the reactions are often studied using synthetic solutions. This work demonstrates the biphasic electro-oxidation of hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) and couples the electrochemical oxidation with the biphasic dehydration of fructose to HMF. The integrated approach eradicates the intermediate HMF purification as the HMF-rich organic product phase is fed directly into the electrochemical flow-cell reactor. Here, HMF is extracted into the aqueous phase and oxidized to FDCA on a Ni(OH)2/NiOOH catalyst in a 0.1 M KOH solution at pH 13. The FDCA then remains in the aqueous phase, enabling direct recirculation of the HMF-containing organic phase. We demonstrate a FDCA yield of close to 80% with a feed from HMF synthesis. Further, we analyze the influence of the phase ratio (organic to aqueous) and current density for biphasic electrochemical oxidation. By adjusting the gap width, we were able to decrease the average cell voltage from 7 V down to 3 V at a current density of 30 mA cm–1. This work presents a promising integrated process for the synthesis of green platform chemicals and provides insight into biphasic solutions in electrochemical conversions.

Combustion synthesis and spark plasma sintering of apatite-tricalcium phosphate nanocomposites

A processing route consisting of Spark Plasma Sintering (SPS) of precursor powders prepared by Solution Combustion Synthesis (SCS) is proposed for the first time for the fabrication of bulk nanostructured biphasic calcium phosphates. The apatite phase content in the product obtained by SCS was maximized using a fuel to oxidizer ratio of 1.1. After a post-synthesis air-annealing step conducted a 700 °C/3 h, powders consisted of 83 wt.% of carbonated apatite, with average crystallite size less than 70 nm, and β- and α-TCP (tricalcium phosphate), as secondary phases. Detailed structural analyses evidenced that the original nanostructure was retained after sintering at 900 °C, with the obtainment of nearly 91% dense, apatite-rich, biphasic bioceramics, with grains size of about 100 nm. The developed nanostructured biphasic material is expected to possess a higher resorption rate than standard microcrystalline hydroxyapatite, which makes it preferable for bone tissue regeneration.

Rational tuning of the cation ratio in metal oxide semiconductor nanofibers for low-power neuromorphic transistors

Wide-bandgap metal oxide semiconductor (MOS) nanofiber neuromorphic transistors (NFNTs) can be potentially used to construct low-power bio-inspired artificial circuits. However, the cation ratio of MOS used for NFNTs is mostly adopted without detailed reasons in literature. In this study, we have for the first time focused on systematically tuning the cation ratio of indium zinc oxide (InZnO)-based NFNTs, fabricated by a low-cost electrospinning technique combined with a facile nanofiber transfer process. These electrical-driven NFNTs based on double-cation InZnO nanofibers can greatly simplify experimental procedures. Among the cation ratios of InxZn1−xO (x = 0.6, 0.7, 0.8, 0.9), we found that NFNTs based on In0.7Zn0.3O exhibited the lowest excitatory postsynaptic currents and offered electrical benefits for low-power operations and synaptic function simulations. The rational tuning of MOS nanofiber composition opens the door for high-performance low-power NFNTs.

Impact of CuO loading for enhanced photocatalytic performance of CdS/CuO photocatalyst on rhodamine 6G dye decomposition under ultraviolet irradiation

In this study, we have incorporated different ratios of copper oxide (CuO) into cadmium sulphide (CdS) to fabricate CdS/CuO binary composites that are utilized as an efficient photocatalyst for rhodamine 6G (R6G) dye decomposition under ultraviolet (UV) exposure. CdS and CuO formed by precipitation and annealing were combined to form composites using a wet physical mixing method. X-ray diffraction (XRD) analysis reveals the preservation of their respective crystalline phases in the composite. Scanning electron microscopy (SEM) images imply that the interface between CuO and CdS improves with increasing CuO content. The coexistence of CuO and CdS compounds could also be verified by Fourier-transform infrared spectroscopy (FTIR) analysis. Also, the UV–Vis absorbance spectra demonstrate a significant increase in absorption intensity accompanied by a bandgap narrowing, which is beneficial for photocatalytic activity. The photocatalytic degradation rate and efficiency are significantly enhanced with CuO loading, with the highest constant rate obtained being as 4.69 × 10-3 min−1. Conclusively, the present CdS/CuO composite can serve as a vital catalyst for environmental sustainability, especially in wastewater remediation.

Effect of Weight Ratio of Graphene Oxide and Carbon Nanotubes on Electrochemical Performance of Planar On-Chip Micro-Supercapacitors

With the wide popularization of 5 G network, the application of miniaturized electronic equipment is being gradually developed, but limited by energy storage technology. Micro-supercapacitors (MSCs) have become the possible direction to solve this problem because of their unique properties. Graphene oxide and carbon nanotubes are very suitable materials for preparing MSCs. However, graphene oxide will overlap due to van der Waals force, and carbon nanotubes will be entangled. In order to solve these problems, reduced graphene oxide and carbon nanotube composite films were prepared by liquid-air interface self-assembly and hydroiodic acid reduction. Planar MSCs with weight ratios of 5:1, 10:1 and 15:1 were prepared by photolithography, and the MSCs of 15:1 show the best comprehensive performance with the area capacitance of 0.905 μF cm−2, the energy density of 0.125 nWh cm−2, the power density of 2263.31 nW cm−2, the time constant of 38 ms, and the capacitance retention of 91.2%.

Optimization of operation mode and design parameters of a finely-dispersed metallic liquid-alloy generator

During the process of designing new devices for the high-speed metallization process, there appears the necessity to define the stable operation range and search for the optimum values of the operation mode and design parameters. This paper describes a process of optimization of a device made for depositing low-melting metal coatings, based on the rocket chamber operation principle. The paper presents an analysis of the objective function surface response metallizer operation performance. On the basis of this analysis the optimal values of fuel mass flow rate and excess oxidant ratio were determined. The choice of fuel and oxidizer throttling orifice cross-section areas was substantiated, the value of the throat cross-section for the metallizer flow-path was found. The expected performance of the designed device was also determined.

Preparation of N/S co-doped graphene/polypyrrole composites for binder-free flexible supercapacitors

Flexible electrodes have been extensively studied and developed, but how to maintain flexibility and increase capacitance at the same time is still challenging. In this work, nitrogen/sulfur co-doped reduced graphene oxide (RGO) and a series of polypyrrole (PPy) composite (RGP-i, i = 1, 2, 3, 4, 5, 6) aerogel materials are prepared by adjusting the mass ratio of graphene oxide (GO) and PPy and using thiourea (CS(NH2)2) as a reducing agent. Binder-free flexible electrodes are assembled by using carbon cloth (CC) as substrates. Among these samples, RGP-5 prepared with the ratio of m(GO):m(PPy) = 1:1 exhibits excellent comprehensive electrochemical performance, with high specific capacitance (394 F g−1 at 1 A g−1) and high capacitance retention (55.4% from 1 to 20 A g−1) simultaneously. The assembled RGP-5//RGP-5 flexible quasi-solid symmetric supercapacitor shows an energy density of 6.25 Wh kg−1 at a power density of 500 W kg−1, and a power density of 2501 W kg−1 at an energy density of 4.37 Wh kg−1. After 1000 cycles of charging and discharging, its capacitance can maintain 80%. The specific capacitance of RGP-5//RGP-5 under different bending angles is almost unchanged, indicating that it shows good flexibility.

The pro- and antineoplastic effects of deoxycholic acid in pancreatic adenocarcinoma cell models

BackgroundCommensal bacteria secrete metabolites that reach distant cancer cells through the circulation and influence cancer behavior. Deoxycholic acid (DCA), a hormone-like metabolite, is a secondary bile acid specifically synthesized by intestinal microbes. DCA may have both pro- and antineoplastic effects in cancers.Methods and resultsThe pancreatic adenocarcinoma cell lines, Capan-2 and BxPC-3, were treated with 0.7 µM DCA, which corresponds to the reference concentration of DCA in human serum. DCA influenced the expression of epithelial to mesenchymal transition (EMT)-related genes, significantly decreased the expression level of the mesenchymal markers, transcription factor 7- like 2 (TCF7L2), snail family transcriptional repressor 2 (SLUG), CLAUDIN-1, and increased the expression of the epithelial genes, zona occludens 1 (ZO-1) and E-CADHERIN, as shown by real-time PCR and Western blotting. Consequently, DCA reduced the invasion capacity of pancreatic adenocarcinoma cells in Boyden chamber experiments. DCA induced the protein expression of oxidative/nitrosative stress markers. Moreover, DCA reduced aldehyde dehydrogenase 1 (ALDH1) activity in an Aldefluor assay and ALDH1 protein level, suggesting that DCA reduced stemness in pancreatic adenocarcinoma. In Seahorse experiments, DCA induced all fractions of mitochondrial respiration and glycolytic flux. The ratio of mitochondrial oxidation and glycolysis did not change after DCA treatment, suggesting that cells became hypermetabolic.ConclusionDCA induced antineoplastic effects in pancreatic adenocarcinoma cells by inhibiting EMT, reducing cancer stemness, and inducing oxidative/nitrosative stress and procarcinogenic effects such as hypermetabolic bioenergetics.

Insight into the non-linear responses of particulate sulfate to reduced SO2 concentration: A perspective from the aqueous-phase reactions in a megacity in Northern China

The non-linear relationship between particle sulfate and SO2 is still unclear. Continuous observations were conducted in a typical city in Northern China from 2017 to 2020. SO2 concentration continually decreased, however, the SO42− concentration and the sulfur oxidation ratio increased in 2018–2019. The major reason might be the variations of sulfate formation by the aqueous-phase reactions, especially for the O2 + TMI oxidation (oxygen catalyzed by transition-metal ions). Particle pH, SO2, and Mn concentration were the main factors affecting the O2 + TMI reaction rate. Sensitivity analysis indicated that the decrease of the O2 + TMI reaction rate caused by SO2 or Mn concentration dropping by half can only offset the increased rate caused by a 0.1 unit decrease in particle pH. Considering the actual atmospheric environment in Northern China, if the particle pH continues to drop, the slow decline of SO2 and Mn concentration may not prevent the increase in the O2 + TMI oxidation rate. In addition to meteorological parameters, the concentrations of SO42−, crustal elements, and total ammonium were the primary factors for the decrease in particle pH in the past 3 years. Therefore, the impact of pH on sulfate formation must be considered when controlling dust and ammonia emissions.

The impact of sprint interval training with or without weight loss on substrate oxidation in adults: A secondary analysis of the i-FLEX study.

Endurance exercise training and weight loss (WL) have been associated with changes in fat oxidation. However, there is limited evidence investigating the impact of sprint interval training (SIT)-induced WL on fat oxidation in adults. To investigate the impact of SIT with or without WL on fat oxidation, 34 adults aged 19-60 years (males, n = 15) took part in 4-week SIT. SIT consisted of 30-s Wingates starting with two intervals and working up to four interspersed with 4 min of active recovery. Fat oxidation was estimated via indirect calorimetry using a metabolic cart during submaximal cycling. Following the intervention, participants were classified into a WL group (weight change >0 kg) or a non-WL group (weight change ≤0 kg). No difference in resting fat oxidation (p = 0.642) and respiratory exchange ratio (RER) (p = 0.646) were observed between the groups. There was a significant interaction for the WL group with increased submaximal fat oxidation usage (p = 0.005) and decreased submaximal RER over the duration of the study (p = 0.017). When adjusted for baseline weight and sex, submaximal fat oxidation usage remained significant (p < 0.05), while RER did not (p = 0.081). The WL group had higher work volume, relative peak power, and mean power than the non-WL group (p < 0.05). Short-term SIT elicited significant improvements in submaximal RER and fat oxidation (FOx) in adults that lost weight, which may be explained by an increase in work volume throughout SIT training.

A Comparison Study the Effect of Doping by Ga2O3 and CeO2 On the Structural and Optical Properties of SnO2 Thin Films

This research deals with the effect of gallium oxide and cerium oxide as dopants on the structural and optical characteristics of tin oxide. Gallium and cerium oxide doped tin oxide was prepared with different doping concentrations (0, 0.03, 0.05 and 0.07) wt. pure and doped tin oxide thin films were prepared by the pulsed laser deposition technique. X-ray diffraction and UV-Visible spectrophotometer were employed to investigate both oxides doping effects. Results showed that all prepared samples have poly-crystalline structure with a preferred plane of crystal growth along (110), where the crystal size grew from 40.3 nm to 64.5 nm and to 43.5 nm for Ga2O3 and CeO2 doped tin oxide thin films, respectively. Transmittance decreased drastically by increasing the doping ratio of gallium oxide. In contrast, it increased by increasing the doping ratio of cerium oxide. The optical energy gap was found to change in nonsystematic sequence with the increase of Ga2O3 doping concentration, while it decreased monotonically by increasing the CeO2 doping concentration.

Mineral Phase Reconstruction and Separation Behavior of Zinc and Iron from Zinc-Containing Dust.

Zinc-containing dust can be found in ironmaking and steelmaking, and it is an important secondary resource of zinc. Zinc-containing dust from an electric furnace was used as a raw material to study the phase transformation behavior of the dust using a calcification roasting process and the zinc-iron separation behavior by using ammonia leaching. The zinc-bearing dust was mixed with CaO and roasted to transform the zinc ferrite into zinc oxide. The results showed that increasing the calcium oxide to dust ratio could promote the conversion of zinc ferrite to zinc oxide. When the calcium oxide ratio reached 60%, the peak of zinc ferrite in the calcined-roasted product in the zinc-containing dust basically disappeared. As the temperature increased, the zinc oxide grains increased but were still smaller than 10 µm. The calcined-roasted product was crushed and ground, and the zinc was leached by ammonia. A zinc-iron recovery rate of 86.12% was achieved by the ammonia leaching. The leachate could be used for zinc extraction by electrolysis. The leaching residue was mainly calcium ferrate, which could be used in sintering production. The proposed process may achieve on-site recovery of zinc-containing dust in steel-making plants.

Controls on the Generation and Geochemistry of Neutral Mine Drainage: Evidence from Force Crag Mine, Cumbria, UK

Neutral mine drainage (NMD) at Force Crag mine in north-west England has a circumneutral pH and high levels of Zn contamination. A long-term geochemical and hydrological dataset from this site was analysed using a novel molar mass balance approach, which demonstrated that the water chemistry is dominated by species released by the oxidation of sulphides: sphalerite (Zn, Cd, Ni), galena (Pb, mostly removed by adsorption to ferrihydrite) and pyrite (Fe, mostly precipitates as ferrihydrite). The calculations show that the sphalerite:galena:pyrite oxidation ratio is ~1:2:1, but the mine water chemistry is dominated by Zn due to the removal of Pb and Fe by adsorption/precipitation. The acidity released by pyrite oxidation is neutralised by the dissolution of calcite and, to a lesser extent, chlorite. The presence of pyrite is responsible both for the release of acidity and the removal of some contaminant metals by adsorption on ferrihydrite. The concentrations of sulphate, Zn, Cd and Ni in the mine water decrease with increasing flow due to dilution; modest increases in metal flux with flow probably reflect increased oxidation due to greater amounts of oxygenated water flowing through the mine. In contrast, Al, Pb and Cu concentrations are positively correlated with flow due to the flushing of these metals adsorbed to ferrihydrite particles. The influence of temperature is relatively subtle; metal fluxes are a balance between abiotic oxidation (which increases at higher temperatures and flows) and bacterially mediated oxidation (which is depressed at high flow rates when temperatures decrease below 10 °C). These conclusions apply to NMD mine water throughout the UK and elsewhere in the world, including mines hosted in both limestone and silicate rocks. The molar mass balance approach, together with synchronous flow and geochemistry data, provides crucial information for effective mine-water-treatment system design by elucidating the critical roles of flow rate and temperature in determining contaminant concentrations and loads.

High-temperature reactor for hydrogen production by partial oxidation of hydrocarbons

Today, conversion of hydrocarbons is one of the most common hydrogen production technologies. This paper presents a design of a high-temperature reactor — the main component of a hydrogen production unit using partial oxidation of hydrocarbons — as well as a physical model of gas generation. It also presents a schematic diagram of an experimental setup as well as results of experimental studies on steady-state modes of partial oxidation in the combustion chamber of a high-temperature reactor for various hydrocarbon feed/oxidant combinations. In the course of the study, we identified patterns that describe how the excess oxidant ratio affects the composition of products of incomplete combustion of hydrocarbons to obtain hydrogen-containing gas of the required composition and parameters for hydrogen production. We propose a method to calculate nominal geometric dimensions of a high-temperature reactor, which makes it possible to estimate its weight and size at the design stage. The paper presents results of experimental studies confirming the adequacy of the proposed method.

Effects of agro-industrial by-products as alumina-silicate source on the mechanical and thermal properties of fly ash based-alkali activated binder

The construction industry has a potential to incorporate various agro-industrial waste for development of sustainable construction materials which will eventually results in a cleaner and healthy environment. This research emphasizes on incorporation of agro-industrial wastes such as Rice husk ash (RHA), fly ash (FA), copper slag (CS), bottom ash (BA) and glass powder (GP) to develop ecofriendly alkali-activated blocks. The research studies the effect of blending alumina-silica rich agro-industrial byproduct with fly ash and the influence of resulting oxide ratios on the thermal, mechanical and physical properties of the proposed binder. The experimental study indicates that the combination of CS with FA resulted in the highest strength of 63 MPa among all the combinations. However, the NaOH molar ratio also plays a crucial role in performance of alkali activated block as all the mixes having 12 M NaOH resulted in higher mechanical performance. The findings suggest that the raw materials, curing temperature and NaOH concentration also contribute towards strength development apart from the oxide ratios like Si/Al, Na/Al and Na/Si. Finally, a comparative performance analysis amongst the agro-industrial waste (used in current study) as an ingredient to develop alkali activated binder was provided.

Integrated ozonation and mineralization of alkyl xanthate: Influence of operation parameters and structure-activity relationship

Xanthate is widely used in the flotation process of sulfide ores, and large amount of flotation wastewater with xanthate is produced and caused serious wastewater pollution due to its excessive usage. This study intensively studied ozonation and various ozone based advanced oxidation processes (AOPs) for alkyl xanthates (AXs) degradation and mineralization, including catalytic ozonation, peroxone and photocatalytic ozonation. The key operation parameters, such as ozone dosage, ratio of different oxidants and solution were studied. All integrated ozonation processes improved the mineralization efficiency of AXs, among which TiO2 photocatalytic ozonation is the most efficient, and the chemical oxygen demand (COD) removal rate can reach 84.9% in 60 min. A quantitative structure-activity relationship (QSAR) model was also established for ozonation of xanthates for the first time, based on quantum chemical calculation of series of xanthate structures and their degradation rate constants in ozonation. It reveals that the main factor affecting the ozonation rate constant is the molecular volume, which is negatively linearly correlated with the length of carbon chain of alkyl substituent group. The degradation intermediates of potassium amyl xanthate were measured by ultraviolet-visible spectroscopy (UV-Vis) and gas chromatography-mass spectroscopy (GC-MS), based on which a degradation path of xanthate was proposed. This work provides deeper understanding of advanced oxidation and mineralization of AXs, and may guide the development of treating technology for flotation wastewater.

Cellular uptake of metal oxide-based nanocomposites and targeting of chikungunya virus replication protein nsP3

Emergence of new pathogenic viruses along with adaptive potential of RNA viruses has become a major public health concern. Therefore, it is increasingly crucial to investigate and assess the antiviral potential of nanocomposites, which is constantly advancing area of medical biology. In this study, two types of nanocomposites: Ag/NiO and Ag2O/NiO/ZnO with varying molar ratios of silver and silver oxide, respectively have been synthesised and characterised. Three metal/metal oxide (Ag/NiO) composites having different amounts of Ag nanoparticles (NPs) anchored on NiO octahedrons are AN-5 % (5 % Ag), AN-10 % (10 % Ag) and AN-15 % (15 % Ag)) and three ternary metal oxide nanocomposites (Ag2O/NiO/ZnO) i.e., A/N/Z-1, A/N/Z-2, and A/N/Z-3 with different molar ratios of silver oxide (10 %, 20 % and 30 %, respectively) were evaluated for their antiviral potential. Cellular uptake of nanocomposites was confirmed by ICP-MS. Intriguingly, molecular docking of metal oxides in the active site of nsP3 validated the binding of nanocomposites to chikungunya virus replication protein nsP3. In vitro antiviral potential of nanocomposites was tested by performing plaque reduction assay, cytopathic effect (CPE) analysis and qRT-PCR. The nanocomposites showed significant reduction in virus titre. Half-maximal inhibitory concentration (IC50) for A/N/Z-3 and AN-5 % were determined to be 2.828 and 3.277 µg/mL, respectively. CPE observation and qRT-PCR results were consistent with the data obtained from plaque reduction assay for A/N/Z-3 and AN-5 %. These results have opened new avenues for development of nanocomposites based antiviral therapies.

High-Efficiency Miniaturized Ultrasonic Nebulization Sample Introduction System for Elemental Analysis of Microvolume Biological Samples by Inductively Coupled Plasma Quadrupole Mass Spectrometry

Sensitive and high-throughput analysis of trace elements in volume-limited biological samples is highly desirable for clinical research and health risk assessments. However, the conventional pneumatic nebulization (PN) sample introduction is usually inefficient and not well-suited for this requirement. Herein, a novel high-efficiency (nearly 100% sample introduction efficiency) and low-sample-consumption introduction device was developed and successfully coupled with inductively coupled plasma quadrupole mass spectrometry (ICP-QMS). It consists of a micro-ultrasonic nebulization (MUN) component with an adjustable nebulization rate and a no-waste spray chamber designed based on fluid simulation. The proposed MUN-ICP-QMS could achieve sensitive analysis at a low sampling rate of 10 μL min-1 with an extremely low oxide ratio of 0.25% where the sensitivity is even higher comparing to PN (100 μL min-1). The characterization results indicate that the higher sensitivity of MUN is attributed to the smaller aerosol size, higher aerosol transmission efficiency, and improved ion extraction. In addition, it offers a fast washout (20 s) and reduced sample consumption (as low as 7 μL). The absolute LODs of the studied 26 elements by MUN-ICP-QMS are improved by 1-2 orders of magnitude compared with PN-ICP-QMS. The accuracy of the proposed method was validated by the analysis of human serum, urine, and food-related certified reference materials. Furthermore, preliminary results of serum samples from patients with mental illnesses demonstrated its potential in the field of metallomics.