Inductive Coupled Plasma Emission Spectrometer Research Articles

Determination of Available Iron Species in Soil by Differential Pulse Voltammetry

AbstractThe available metal species are significant for the growth and development of plants. Thus, it is important to detect the content of available metal species in soil at real‐time. Available iron in soil used to be determined by atomic absorption spectrometry or inductive coupled plasma emission spectrometer (ICP) method, which is quite expensive and not easy to operate, especially for farmers. This paper reports a rapid electrochemical method only by applying an electrochemical workstation equipment. Compared to stripping voltammetry method, differential pulse voltammetry (DPV) in this work can detect the available iron species accurately just by directly using the soil extraction solution and does not need the acidic digestion procedure. The DPV strategy we adopted in this work has the advantages of convenience, rapidity and high precision, and can reach the measurement level of ICP method.

Pollution Characteristics and Source Analysis of Heavy Metals in Soils in Yellow River Cultural Park Based on APCS-MLR and PMF Receptor Model

With open spaces and good ecological environments, urban parks have become the first choice for the leisure and entertainment of many people. Therefore, the quality of park soil environments has gradually attracted the extensive attention of scholars. In this study, we take the Yellow River Cultural Park, a typical human disturbance area in the lower reaches of the Yellow River, as the research area to discuss the characteristics and sources of heavy metal pollution in the soil. Thirty-three soil surface samples were collected from the Yellow River Cultural Park, and the contents of seven heavy metals (Cr, Ni, Cu, Zn, Cd, Pb, and As) were determined using an inductively coupled plasma emission spectrometer (ICP-AES) and an inductively coupled plasma mass spectrometer (ICP-MS). The geo-accumulation index and geo-statistics method were used. Meanwhile, the absolute factor analysis-multiple linear regression (APCS-MLR) receptor model and positive matrix factorization (PMF) analysis model were employed to reveal the sources of soil heavy metals. The results showed that the average contents of heavy metals (Cd, Zn, Cu, Pb, and As) in the surface soil of the study area were 4.62, 1.78, 1.41, 1.08, and 1.03 times higher than the background values of soil elements in the tidal soil area of the lower reaches of the Yellow River, respectively. Except for Zn, the contents of other elements were lower than the corresponding values of soil elements in different regions along the Yellow River Basin. Among the seven heavy metal elements, the coefficients of variation of Cd and As were greater than 50%, showing obvious spatial variability. The decreasing trend of the accumulation index of the seven elements was Cd>Zn>Cu>Ni>Pb>As=Cr, and the element Cd belonged to the middle pollution category, which was obviously accumulated in the surface soil. The spatial distribution of heavy metals in the soil differed:the high contents of Cr, Cu, and Ni were distributed in the southwest and northeast, and the high-value areas of Cd and Pb were consistent with the areas of human activity intensity. The high-value areas of Zn and As were located in the center of lacustrine sediments. The combined results of the APCS-MLR and PMF models suggested that the first pollution source of soil heavy metal elements in the Yellow River Cultural Park could have been a natural source, the second pollution source may have been a transportation source, and the third source of pollution was judged as a mixed source. Human activities such as transportation sources and mixed sources were the main sources of heavy metal soil pollution, and Cr, Cu, and Ni were affected by natural factors. The contribution rates of APCS-MLR were 46.67%, 24.11%, 16.12%, and 13.10%, respectively, and the contribution rates of PMF were 35.50%, 35.48%, and 29.02%, respectively. This research can provide a basis for improving the ecological environment quality of the park and improving the health level of the population and can also provide support for the ecological environment risk management and comprehensive management along the Yellow River.

Structural Characterization of Zinc-Sucrose Complex and Its Ability to Promote Zinc Absorption in Caco-2 Monolayer Cells and Mice.

Sucrose emerges as a metal-ion chelating agent with excellent stability that may increase metal-ion absorption. This study aimed to characterize the structure of zinc-sucrose complex and investigate its ability to promote zinc absorption in Caco-2 monolayer cells and mice. Based on the results of the inductively coupled plasma emission spectrometer (ICP-ES), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX), and Fourier transform infrared spectroscopy (FT-IR), it can be inferred that zinc and sucrose were chelated at a 1:1 ratio, with the hydroxyl groups playing a significant role. The Caco-2 monolayer cell model revealed that zinc-sucrose complex increased the amount of zinc uptake, retention, and transport in a dose- and time-dependent manner. Through the upregulation of genes and proteins for ZIP4, MT1, and DMT1, treatment with zinc-sucrose complex improved the proportion of absorbed zinc utilized for transport compared to ZnCl2 (26.21 ± 4.96 versus 8.50 ± 1.51%). Pharmacokinetic analysis of mice confirmed the zinc absorption-promoting effect of zinc-sucrose complex, as indicated by the considerably higher serum zinc level (4.16 ± 0.53 versus 2.56 ± 0.45 mg/L) and intestinal ZIP4, MT1, and DMT1 gene expression than ZnCl2. Further treatment of different zinc channel inhibitors and CETSA demonstrated the direct interaction of zinc-sucrose complex with ZIP4 protein and ZIP4-mediated cellular transport of zinc-sucrose complex. These findings provide a novel insight into the zinc absorption-promoting mechanism of zinc-sucrose complex, which could be used as an ingredient in functional foods to treat zinc deficiency.

Sources and health risk assessment of water-soluble and water-insoluble metals in road and foliar dust in Xi'an, Northwest China

Road dust pollution is still an important environmental problem in the cities of northwest China. To better understand the risk exposure and sources of unhealthy metals in road dust and foliar dust, the dust samples were collected in Xi'an city, Northwest China. The sampling period was during December 2019 and 53 metals in the dust were analyzed using Inductive Coupled Plasma Emission Spectrometer (ICPA-RQ). Compared to road dust, most metals are found in relatively higher concentrations in foliar dust, especially water-soluble metals, with Mn being 3710 times more abundant in foliar dust. However, the regional characteristics of road dust are more pronounced, i.e., the concentrations of Co and Ni are six times higher in industrial manufacturing areas than in residential areas. The results of the non-negative matrix factorization and principal component analysis source analyses demonstrate this difference, the dust in Xi'an is mainly from transportation (63 %) and natural sources (35 %). From the emission characteristics of the traffic source dust, brake wear is the main cause of traffic source, accounting for 43 %. However, the metal sources in each principal component of foliar dust show a more mixed state, which is consistent with the results of regional characterization. The health risk evaluation shows that traffic sources are the main risk source and contribute 67 % to the total risk. Among them, Pb from tire wear is the main contribution to the total non-carcinogenic risk for children, which is close to the risk threshold. In addition, Cr and Mn are also worthy of attention. The above results all emphasize the contribution of traffic emissions, especially the non-tailpipe emission component, to dust emissions and health risks. Therefore, controlling vehicle wear and tear and exhaust emissions should be the main way to improve air quality, such as traffic control and improvement of vehicle component materials.

Chemical Composition and Microstructure Characterization of High Purity CuMn Alloy for Integrated Circuit

High purity copper and copper alloy targets are the key supporting materials for the interconnection of integrated circuits in advanced processes. In this article, the chemical composition and microstructure of Cu-0.6wt%Mn alloy were characterized by means of Glow Discharge Mass Spectrometry, Inductive Coupled Plasma Emission Spectrometer, Optical Microscope and Scanning Electron Microscope. The results show that the total impurity content for Cu-0.69wt%Mn alloy is less than 1 ppm. The three key impurities contents of Ag and Fe and Si could meet the requirement of electronic materials for integrated circuits by use of high purity raw material and appropriate melting and casting methods. Mn content at different positions along the diameter direction fluctuates slightly between 0.66~0.72 wt%, and completely distributed uniformly in the Cu matrix without any trace of aggregation. Due to the influence of raw materials and casting technology, defects such as porosity and carbon inclusion are easy to appear in as-cast microstructure. Therefore, it is necessary to develop new casting mould and casting processing to improve the quality of ingots.

A Planar Disk Electrode Chip Based on MWCNT/CS/Pb2+ Ionophore IV Nanomaterial Membrane for Trace Level Pb2+ Detection.

Unlike conventional lead ion (Pb2+) detecting methods, electrochemical methods have the attractive advantages of rapid response, good portability and high sensitivity. In this paper, a planar disk electrode modified by multiwalled carbon nanotube (MWCNTs)/chitosan (CS)/lead (Pb2+) ionophore IV nanomaterial and its matched system are proposed. This system presented a good linear relationship between the concentration of Pb2+ ions and the peak current in differential pulse stripping voltammetry (DPSV), under optimized conditions of -0.8 V deposition potential, 5.5 pH value, 240 s deposition time, performed sensitive detection of Pb2+ within sensitivity of 1.811 μA · μg-1 and detection limit of 0.08 μg · L-1. Meanwhile, the results of the system in detecting lead ions in real seawater samples are highly similar to that of inductively coupled plasma emission spectrometer (ICP-MS), which proved a practicability for the system in detection of trace-level Pb2+.

Evaluation of ash /slag heavy metal characteristics and potassium recovery of four biomass boilers

The utilization of biomass combustion for electricity generation has grown an importance and popularity. However, effective management of ash produced during biomass combustion is a major challenge. To analyze the ecological risk of heavy metals and ash characteristics in biomass ash, an inductive coupled plasma emission spectrometer (ICP) and X-ray diffraction (XRD) were used. The effects of temperature (20 °C, 40 °C, 60 °C), stirrer time (1h, 2h, 3h), and water-ash ratio (1:1, 2:1, 3:1) on potassium extraction were studied. The results show that the ecological risk index (RI) values of the fly ash and slag samples are very high, and all samples have very high risk (VHR) mainly due to Cd higher toxicity than other heavy metals. The main constituents of slag are aluminosilicate and SiO2, whereas fly ash contains CaSO4, KCl, SiO2, and KAlSi3O8. The fly ash from straw-fired biomass boiler contains more potassium, making it the most suitable raw material for the actual potassium extraction. In addition, temperature and stirrer time have little effect on potassium solubility while the effect of water-ash ratio is significant. Therefore, the most cost-effective potassium extraction method is water washing at room temperature with a stirrer time of about 1 h, a water-ash ratio of about 2:1, and leaching fly ash multiple times with incorporating the water recycling.

Restraining Shuttle Effect in Rechargeable Batteries by Multifunctional Zeolite Coated Separator

AbstractThe detrimental shuttle of soluble species from cathode to anode inside battery, is a critical thorn limiting stability and reversibility of rechargeable battery. Herein, an ordered pore‐window of zeolite molecular sieve is employed to effectively block shuttle of soluble matters, and prepared zeolite powder into thin zeolite layer (5 µm thick) coated on celgard separator (zeolite@celgard) with flexible and grid‐scale fabrication features. External pressure is applied to press zeolite@celgard to reduce existed interparticle gaps among zeolite particles. The separation function toward soluble species and attached H2O scavenger role of zeolite@celgard are demonstrated via 1H/19F Nuclear Magnetic Resonance spectra, Inductive Coupled Plasma Emission Spectrometer and X‐Ray Photoelectron Spectroscopy results collected from Li/LiMn2O4 battery, time‐dependent in situ Raman tests in Li/S battery, and penetration experiments of redox mediator shuttle in Li/O2 battery. Replacing typically‐used celgard/glassfiber separators, a series of side reactions (active material outflowing, low coulombic efficiency, and anode corrosion) induced via shuttle of soluble species are addressed, resulting in battery performance improvement of Li/LiMn2O4, Li/S, and Li/O2 batteries. Both scientific hypothesis of utilizing pore‐size effect of zeolite for physically block soluble species, and cost‐effective, grid‐scale, and flexible zeolite‐based separators can be extended to other rechargeable battery systems based on flowing/soluble species.

Poly (hydroxyethyl methacrylate - acrylic acid) microspheres loaded with magnetically responsive Fe3O4 nanoparticles for arterial embolization, drug loading and MRI detection

In recent decades, transcatheter arterial embolization (TAE) has been attached great importance in the noninvasive vascular interventional therapy for treating various diseases. In this study, a novel magnetic embolic agent of Fe3O4-loaded hydrophilic poly (hydroxyethyl methacrylate - acrylic acid) microspheres (FPHA-Ms) was constructed using inverse suspension polymerization and sequential in situ co-precipitation method. The loading of Fe3O4 nanoparticles in FPHA-Ms was verified by infrared spectrum, vibrating sample magnetometer, X-ray diffraction and X-ray photoelectron spectroscopy, respectively. The weight percentage of iron content in lyophilized FPHA-Ms was measured by inductive coupled plasma emission spectrometer. The morphology, particle size distribution, equilibrium water content, elasticity, drug loading & eluting capacity, biosafety, magnetic resonance imaging (MRI) detectability and embolic efficacy of FPHA-Ms were systematically evaluated, respectively. FPHA-Ms possessed many merits including spherical shape, uniform and wide size range, considerable water content, high drug loading, sustained drug release and good elasticity and biocompatibility. The in vivo experiments showed FPHA-Ms could effectively block the blood supply and could be detected by MRI device. All the results proved that FPHA-Ms could serve as a novel MRI-visible multi-functional embolic agent for clinical vessel embolization, drug loading and MRI tracing in the near future.

Preparation of carbon nanotubes with high filling rate of copper nanoparticles

Performance of carbon nanotubes (CNTs) can be adjusted by filling their cavities with guest materials. In this study, Cu nanoparticles are filled into CNTs via wet chemical method. To improve the filling efficiency, oxygen-containing functional groups (OCFGs) are introduced onto the tube walls of CNTs by acid treatment. The defects and pore size distribution on CNTs are detected and quantified by N2 adsorption-desorption experiment, Raman spectra, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). Morphologies of CNTs before and after filling treatment are observed by transmission electron microscope (TEM). The filling rate is characterized by inductively coupled plasma emission spectrometer (ICP) and thermal gravimetric analysis (TGA). The results indicate that the OCFGs can not only improve the hydrophilicity of CNTs, but also greatly affect the filling rate of CNTs. The filling rate of CNTs acid-treated for 24 h (1.99 wt% tested by TGA) is significantly lower than that of acid-treated for 8 h (12.11 wt% tested by TGA), which can be ascribed to the fact that excessive OCFGs could hinder Cu2+ ions from entering the cavity of CNTs. The obtained results can provide a new perspective for the application of CNTs in composite preparation and related fields.

Improving the cycling stability of biochar electrodes by purification via ion exchange

Excellent long-term cycling stability and safety are the basic qualities of electrode materials in electrochemical energy storage equipment. Nevertheless, the inferior cycling stability and device safety caused by impurity ions constrain their practical application. Thus, it is essential to purify biomass-based carbon materials when they are used as electrodes in the field of energy storage. Herein, four purification methods are studied, including water-washing, acid-pickling, ion exchange and ultrasonic wave, respectively. Particularly, trace elements are detected by inductive coupled plasma emission spectrometer and ion chromatography to explore the impurity removal effects. The results suggest that ion exchange possesses the best impurity-cleaning effect among the four methods. In addition, the supercapacitor employing the biochar electrode material with minimum impurities exhibits excellent ultra-long cycling stability. In symmetric supercapacitors, the capacitance retentions are 86.7% after 120000 cycles using 6 M KOH electrolyte and 70% after 30000 cycles using 1 M MeEt3NBF4/PC electrolyte at 4 A/g. Furthermore, we reveal the influence mechanism of metal ion impurities on cycling stability and impedance. In summary, the elaborate study provides a feasible method to solve the problem of impurity removal and designs suitable biomass carbon materials for commercial application in the energy storage field.

Influence of phosphorus impurities on the structure and performance of cellulose-ether-modified gypsum

This study examined the influence mechanism of phosphorus impurities in phosphogypsum on the structure and properties of gypsum. The influence of four phosphorus impurities, namely Ca3(PO4)2, CaHPO4, H3PO4, and Ca(H2PO4)2 on the hydration process, water retention, and mechanical properties of hydroxypropyl methyl cellulose ether (HPMC)-modified gypsum was examined through inductive coupled plasma emission spectrometer, scanning electron microscopy, and nanoparticle size testing. The soluble phosphorus impurities exert a significant retarding effect on HPMC-modified gypsum, which decreases the heat of hydration in the early stage. Moreover, soluble phosphorus impurities significantly decrease the water retention and compressive and flexural strengths of modified gypsum. Although slightly soluble CaHPO4 exerts a similar adverse influence on the structure and properties of modified gypsum, the effect is weaker than that of soluble phosphorus impurities. Insoluble Ca3(PO4)2 does not affect the properties of modified gypsum. Soluble phosphorus in the liquid phase decreases the supersaturation of the gypsum solution and metathesises with the Ca2+ in the solution to produce insoluble calcium phosphate. This product covers the surface of the crystal nucleus, delays the hydration reaction of gypsum, and decreases the amount of heat released in the early hydration process. Moreover, a coarse overlap of the crystal growth and loose structure of the hardened body is observed, and the flexural and compressive strengths decrease. Increase in the amount of soluble phosphorus in the solution decreases the polarity of the hydroxyl group in the HPMC molecule and strength of the hydrogen bond within the association complex. This phenomenon leads to the disintegration of the large colloidal association and the less swelling, owing to which the HPMC molecule cannot effectively block the water transmission channel in the mixture, resulting in decreased water retention of the HPMC-modified gypsum.

Facile hydrothermal synthesis of urchin‐like NiCo 2 O 4 as advanced electrochemical pseudocapacitor materials

The urchin-like NiCo2O4 material was prepared by a one-step hydrothermal method. The optimal synthetic conditions were systematically investigated by an orthogonal test method and single factor of hydrothermal time to evaluate the influence of sample morphology and electrochemical performance. The synthesis conditions for preparing NiCo2O4 with different morphologies were systematically studied. In the single factor experiment, when the hydrothermal time is 6, 12, 16, and 24 hours, the corresponding morphologies are urchin-like (NCO-U), flower-like (NCO-F), sheet-like (NCO-S), and block-like (NCO-B), respectively. The element content of the prepared materials under different synthesis conditions was tested by an inductive-coupled plasma emission spectrometer, and an interesting phenomenon was found. As the reaction time increases, the content of Ni+ gradually decreases and the content of Co+ gradually increases, which may be one of the factors that affect the morphology and electrochemical performance of the material. The specific capacitances of NCO-U, NCO-F, NCO-S, and NCO-B are calculated to be 914.3, 392.2, 313.3, and 277.4 F g−1, respectively, at a current density of 1 A g−1. Benefiting from the large specific surface area and rich oxygen vacancy, the as-fabricated urchin-like NiCo2O4 as electrode materials for supercapacitor demonstrates its promising application potential for supercapacitors.

Effect of Nano-Y2O3 Content on Microstructure and Mechanical Properties of Fe18Cr Films Fabricated by RF Magnetron Sputtering.

In this work, FeCr-based films with different Y2O3 contents were fabricated using radio frequency (RF) magnetron sputtering. The effects of Y2O3 content on their microstructure and mechanical properties were investigated through scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), inductive coupled plasma emission spectrometer (ICP) and a nanoindenter. It was found that the Y2O3-doped FeCr films exhibited a nanocomposite structure with nanosized Y2O3 particles uniformly distributed into a FeCr matrix. With the increase of Y2O3 content from 0 to 1.97 wt.%, the average grain size of the FeCr films decreased from 12.65 nm to 7.34 nm, demonstrating a grain refining effect of Y2O3. Furthermore, the hardness of the Y2O3-doped FeCr films showed an increasing trend with Y2O3 concentration, owing to the synergetic effect of dispersion strengthening and grain refinement strengthening. This work provides a beneficial guidance on the development and research of composite materials of nanocrystalline metal with a rare earth oxide dispersion phase.

Electrochemical synthesis of Ti–Al–V alloy by chlorination of Ti2O3 and V2O3 in AlCl3-containing molten chloride salt

Abstract The current study proposes a novel method of preparing Ti–Al–V alloy by electrochemical co-deposition by adding Ti2O3 and V2O3 into the molten salt system. The influence of chlorination of Ti2O3 and V2O3 in KCl–LiCl–MgCl2–AlCl3 melt was studied by inductively-coupled plasma emission spectrometer (ICP-AES) and X-ray diffractometer (XRD). The results revealed that the optimal chlorination temperature ranged from 600 °C to 700 °C and the main chlorination products were TiCl3, VCl3, and Al2O3 byproduct. The electrochemical behavior of Ti3+, V3+ and Al3+ in a molten AlCl3-containing chloride salt was investigated by cyclic voltammetry. The stepwise reduction in the cathode could be given as: V3+→V2+, Ti3+→Ti2+, V2+→V, Ti2+→Ti, Ti2+/V2+/Al3+→Ti–Al–V alloy. The electrolytic products were also characterized by XRD and scanning electron microscopy (SEM), equipped with energy dispersive spectroscopy (EDS). The results demonstrated that, as metallic Al was used as an anode, a dendritic Al3Ti alloy and Al sheet were obtained after the addition of Ti2O3 into the KCl–LiCl–MgCl2–AlCl3 melt. However, the presence of both Ti2O3 and V2O3 resulted in fishbone-like Al3Ti, Al3Ti0.8V0.2 and Al3Ti0.666V0.333 alloys, as well as dense granules of metallic Al.

LIBS characterization of algal fouling on insulators

Algae contamination accumulated on the surface of insulators will affect the electrical properties of insulators. At present, the characterization method of algae contamination is the image method, which determines the distribution of algae contamination through colour. The detection results are affected by environmental changes and the growth state of algae. This paper puts forward a method of detecting polluted insulator surface with algae by using laser-induced breakdown spectroscopy (LIBS) technique, combined with the scanning electron microscope (SEM), inductively coupled plasma emission spectrometer (ICP), analyzed by the spectra of algae contamination. Mg, Ca, Fe are selected as the analytical element. The classification of algae contamination, non-algae contamination and no contamination are realized with the principal component analysis (PCA). The research results are of great significance for characterization of algal pollution on insulator surface by LIBS.

Synthesis, characterization and photoluminescence properties of an organic–inorganic hybrid monolacunary Keggin-type polyoxotungstate

An organic–inorganic hybrid lanthanide-based polyoxometalate (Ln-POM) [N(CH3)4]3K2[Tb(C7H5O3)(H2O)2(α-PW11O39)]·10H2O (1) was synthesized and further characterized by single crystal X-ray diffraction analysis, elemental analyses, Inductive Coupled Plasma Emission Spectrometer (ICP), powder X-ray diffraction (PXRD), Fourier transform infrared (FTIR) spectroscopy, solid-state UV/vis spectrum and thermogravimetric analyses (TGA). Single-crystal X-ray diffraction analyses indicated that both organic ligand and [α-PW11O39]7− group directly bind Tb3+ center for the formation of polyanion in 1. The photoluminescence property of 1 was investigated at room temperature, and the results showed that compound 1 exhibits lower energy transfer efficiency from POM fragment and organic ligand to Tb3+ ion. Furthermore, time-resolved emission spectroscopy indicates that the photoexcitation O → M ligand to metal charge transfer (LMCT) of POM fragments and organic ligand can sensitize the Tb3+ ions through intramolecular energy transitions in 1.

Study of RHO zeolite with different cations for CO 2 /CO separation in pressure swing adsorption

A series of cation-exchanged RHO zeolites, including H-RHO, Li-RHO, Na-RHO, K-RHO, Cs-RHO, Cd-RHO and Pb-RHO, were prepared, and the samples were characterised by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, thermogravimetric analysis, inductive coupled plasma emission spectrometer and N2-BET. The CO2 and CO adsorption behaviours of the samples were measured at 298 K and 0–10 bar. The Langmuir equation was used to fit adsorption isotherms to compare the separation effect of these RHO zeolites. The results show that extra-framework cations can effectively adjust the pore size of RHO. Not only it depends on the size of the cation radius, but other factors also play an important role, such as the position of the cation. Besides, compared with CHA structure, RHO structure has better CO2/CO separation performance. In all researched cationic forms of RHO, Li-RHO, Cd-RHO and Pb-RHO have excellent CO2/CO separation effects. Among them, the pore size of Cd-RHO is significantly reduced, thereby restricting the entry of CO more effectively, ultimately leading to greater shape selectivity. Cd-RHO not only has the highest CO2 saturated adsorption capacity and CO2 working capacity but also has relatively excellent CO2/CO selectivity, resulting in the sorbent selection parameter (S) is also the largest.

Antibacterial effect of Ag-PMANa modified cotton

In this study, the cotton fabric was treated with silver (Ag)-doped sodium polymethacrylate (PMANa) to provide it with antibacterial properties. Ag-doped PMANa, a stable, transparent, and water-soluble organic polymer with antimicrobial activity, was obtained by sequestering Ag+ with the –COO− groups of PMANa polymer via ion exchange method. The antibacterial activity of the Ag-PMANa was evaluated by minimum inhibitory concentration and minimum bactericidal concentration testing using E. coli and S. aureus as representative strains of Gram-negative and Gram-positive bacteria, respectively. Then, the cotton fibers were impregnated with this polymer, and the successful loading was confirmed by characterization of chemical, structural, and morphological properties. The amount of Ag ions released from the antibacterial cotton was determined by Inductive Coupled Plasma Emission Spectrometer. Antimicrobial property against E. coli and S. aureus of the modified cotton was assessed by the oscillation method and compared with that of untreated cotton. The modified cotton fabrics were measured to have an excellent antibacterial effect. Furthermore, the results also showed that the modified cotton is highly stable under washing conditions and under exposure to different light conditions. Intrinsic properties of modified cotton were preserved compared to those of pristine cotton. The morphological characteristics of bacteria were evaluated by SEM and the reducing sugars and proteins that leaked from E. coli and S. aureus were detected to preliminarily explore the antimicrobial mechanism of Ag+. The material prepared herein shows high potential for a broad range of applications in biomedical field.

Synthesis of high-performance Ni/Ce0.8Zr0.2O2 catalyst via co-nanocasting method for ethanol dry reforming

A Ni/Ce0.8Zr0.2O2 catalyst (NiCeZr-N) was synthesized by a facile co-nanocasting technique for syngas production from ethanol dry reforming. In addition, a series of characterization techniques, such as transmission electron microscopy (TEM), X-ray diffraction (XRD), inductive coupled plasma Emission Spectrometer (ICP), X-ray photoelectron spectroscopy (XPS), Raman and hydrogen temperature programmed reduction (H2-TPR) were selected to evaluate the physicochemical features of the as-prepared catalysts. Indeed, the results indicated that NiCeZr-N catalyst prepared by co-nanocasting method had a smaller particle size (<5 nm), relatively higher specific surface area (39 m2/g) and stronger metal-support interaction in comparison with another model catalyst obtained from conventional co-precipitation method (NiCeZr-P). Expectedly, these positive factors enabled NiCeZr-N catalyst to exhibit better activity and stability. Typically, ethanol is completely converted by using NiCeZr-N as catalyst and heating to 700 °C, and CO2 conversion was as high as 65.3%. Interestingly, H2/CO was close to 1.1 at 650 °C, which could be used as feedstocks of Fischer-Tropsch process. Particularly, no obvious fluctuation of ethanol conversion and the product selectivity was observed during 40 h time-on-stream stability test.