Analytical‐Based Methodologies for Examining the In Vitro Absorption,Distribution, Metabolism,and Elimination (ADME) of Silver Nanoparticles

The clinical applications of silver nanoparticles (AgNPs) remain limited due to the lack of well‐established methodologies for studying their nanokinetics. Hereby, the primary goal is to adapt a suite of analytical‐based methodologies for examining the in vitro absorption, distribution, metabolism, and elimination of AgNPs. Vero 76 and HEK 293 cells are exposed to ≈10‐nm spherical AgNPs⁺ and AgNPs^? at relevant concentrations (0–300 µg mL^?1) and times (4–48 h). Absorption: Inductively coupled plasma optical emission spectroscopy (ICP‐OES) demonstrates that the two AgNP formulations are not bioequivalent. For example, different bioavailabilities (C _maximum < 20.7 ± 4% and 6.82 ± 0.4%), absorption times (T _maximum > 48 and ≈24 h), and absorption rate laws (first‐ and zeroth‐order at 300 µg mL^?1) are determined in Vero 76 for AgNPs⁺ and AgNPs^?, respectively. Distribution: Raman and CytoViva hyperspectral imaging show different cellular localizations for AgNPs⁺ and AgNPs^?. Metabolism: Cloud point extraction (CPE)‐tangential flow filtration (TFF) reveal that ≤ 11% ± 4% of the administered, sublethal AgNPs release Ag⁺ and contribute to the observed cytotoxicity. Elimination: ICP‐OES‐CPE suggests that AgNPs are cleared via exocytosis.     

Determination of Inclusion Characteristics in the Asea‐SKF Process using the Modified Spark‐Induced OES Technique as a Complement in Studying the Influence of Top Slag Composition

The spark‐induced modified optical emission spectroscopy (OES) technique developed by Ovako Steel makes it possible to rapidly determine inclusion characteristics in steel samples. In earlier investigations using the modified spark‐induced OES technique for steel samples taken from billets, predicted oxygen contents agreed well with results from conventional melt extraction analyses. In this investigation, samples taken during ladle treatment in an ASEA‐SKF ladle furnace were analysed using the modified OES technique. When comparing the results with inclusion characteristics determined by conventional analysis, similar trends were found. Plant trials were also carried out where three different top slag compositions were used. The purpose was to evaluate if the modified OES technique can be used to study the effect of changes in the refining operation on inclusion characteristics. Results indicated that the modified OES technique could be used to determine the effect of a changed slag composition on the inclusion characteristics in the steel. Since the modified OES method provides rapid feedback of inclusion characteristics, it has the potential of being used for faster optimisation of ladle refining operations.     

Estimation of plasma parameters in the process of micro-scale powder plastic and characteristics of its products

The temperature and density of plasma jets were estimated with a Boltzmann plot and Stark broadening of Ar I (696.54 nm) lines by optical emission spectroscopy (OES) in the process of plasma plastic, and the morphology and microstructure of tungsten (W) powders were investigated by scanning electron microscope (SEM) and x-ray Diffraction (XRD), respectively. The results show that the assumption of local thermodynamic equilibrium (LTE) was invalid at the end of the plasma jets, and earlier than this after the injection of tungsten powder. The temperature and electron density of the plasma jets were up to about T=6797 K with Q_c=50 slpm and n_e=1.05×10¹⁶ cm⁻³ with Q_s=115 slpm at Z=60 mm, respectively, and both dropped rapidly with the injected tungsten powders of 20 μm. After the plasma plastic process, the spherical tungsten powders were prepared and there were some satellite particles on the surface of the spherical products. The tungsten powders were both composed of a single equilibrium α-W phase with a body centered cubic (bbc) crystal structure before and after plasma treatment.     

Evolution of plasma parameters in an Ar-N2/He inductive plasma source with magnetic pole enhancement

Magnetic pole enhanced inductively coupled plasmas(MaPE-ICPs) are a promising source for plasma-based etching and have a wide range of material processing appUcations.In the present study Langmuir probe and optical emission spectroscopy were used to monitor the evolution of plasma parameters in a MaPE-ICP Ar-N_2/He mixture plasma.Electron density(n_e) and temperature(T_e),excitation temperature(T_(exc)),plasma potential(V_p),skin depth(δ) and the evolution of the electron energy probability function(EEPF) are reported as a function of radiofrequency(RF) power,pressure and argon concentration in the mixture.It is observed that n_e increases while T_e decreases with increase in RF power and argon concentration in the mixture.The emission intensity of the argon line at 750.4 nm is also used to monitor the variation of the 'high-energy tail' of the EEPF with RF power and gas pressure.The EEPF has a'bi-Maxwellian' distribution at low RF powers and higher pressure in a pure N_2 discharge.However,it evolves into a 'Maxwellian' distribution at RF powers greater than 70 W for pure N_2,and at 50 W for higher argon concentrations in the mixture.The effect of argon concentration on the temperatures of two electron groups in the 'bi-Maxwellian' EEPF is examined.The temperature of the low-energy electron group T_L shows a decreasing trend with argon addition until the 'thermalization' of the two temperatures occurs,while the temperature of high-energy electrons T_H decreases continuously.     

Essential and trace elements content of commercial infant foods in the UK

There is a paucity of data in respect of the nutritional quality of complementary foods for infants and young children aged between 6 and 12 months. The primary objective of this study was to examine nutritive values of such complementary infant food on the UK market in order to ascertain their suitability relative to dietary guidelines for the 6–9 months age group. Quantitative analyses were conducted on eight different products representing four popular brands (meat and vegetable based) currently on sale in the UK. Eight major mineral and trace elements, namely: calcium, copper, magnesium, iron, zinc, potassium, sodium and selenium were measured by ICP–OES and ICP–MS. The results of these studies were referenced to the Recommended Nutrient Intake (RNI) values for 6–9 months old children, and a menu of entire daily intake of minerals and trace elements was composed taking into consideration the nutrient and energy intake from milk consumption. Based on these comparisons, all the food samples studied in this work contained less essential minerals than expected from the RNI values except for potassium in meat and vegetable based recipes. These results suggest that commercial complementary infant foods on the UK market may not contain the minimum levels of minerals required for the labelling declaration of micronutrient content (Commission Directive 2006/125/EC). This provides opportunities and scope for product optimisation to improve their nutritive value.     

ICP—OES法测定钛合金中A1元素含量的不确定度评定

将钛合金样品用10mL1：1硫酸溶解后,用ICP—OES法对其中A1元素含量进行测定,测得样品中W（A1）=6．91％。对测定过程中的不确定度来源进行了分析,依据不确定度评定的步骤,计算得到了各分量标准不确定度及合成标准不确定度,W（A1）测定结果的扩展不确定度为U=0．17％,K=2。     

Optimization of a slurry dispersion method for minerals and trace elements analysis in infant formulae by ICP OES and FAAS

Infant formula developed by manufacturers requires a rigorous control of composition, particularly those elements added routinely in an attempt to mimic the mineral composition of human milk. A total of 97 different types of powdered infant formulae (preterm, adapted starter, adapted follow-up, toddler, specialised and soy-based formulae) commercially available in Spain were studied. It is noteworthy great differences in mineral (Ca, P, Mg) and trace element (Zn, Fe, Cu, Mn) contents found between analysed and listed in label information. The development of a fast, simple and direct slurry method for the determination of these essential micronutrients in infant formula by inductively coupled plasma optical emission spectrometry (ICP OES) and flame atomic absorption spectrometry (FAAS) was performed in order to help in quality control tasks. Infant formula samples were solubilised using different amounts of several different solvents. An addition of 250 μL of a solution 10% tetramethylammonium hydroxide and 25% ammonium hydroxide were required for the accurate quantification of Ca and P, Mg, Zn, Fe, Cu and Mn, respectively. The standard reference material 1549 non-fat milk powder was solubilised to compare the validity of assayed methodology following slurry nebulisation and traditional microwave-assisted acid digestion method. Good agreement of the analytical results by both ICP OES and FAAS, with the certified values was obtained. Method performance parameters (accuracy, precision and methodological detection limits) were determined for studied elements to check the quality and usefulness of the optimised slurry method. The analytical procedure was applied successfully to the analysis of a representative group of infant formulae. Levels of analysed elements were graphically represented, showing an acceptable comparability between slurry and acid-mineralisation method set by linear correlation coefficients and slopes close to the unit. The described simple and slurry method is appropriate, as an attractive alternative, for routine control analysis of added essential elements in infant formulae regardless of predominant protein type used in manufacture.     

Corrosion protection of cold-rolled steel by zinc-rich epoxy paint coatings loaded with nano-size alumina supported polypyrrole

High porosity and intense galvanic function related low electrolytic barrier profile and fast delamination of zinc-rich paints (ZRPs) are addressed by the utilisation of intimately structured, highly dispersed, polypyrrole (PPy) deposited alumina particles (PDAPs) embedded zinc-rich hybrid paints. The more globular but less-packed structure type PPy-contained water-solvent-prepared PDAPs-composited hybrids comprising spherical zinc pigment at 70 wt.%, provided moderate galvanic function with enhanced electrolytic barrier properties. In addition, the less globular structured but well-packed PPy-comprised aqueous ethanol-solvent-prepared PDAPs-composited hybrid coatings indicated highly efficient suppressed galvanic function and improved barrier properties, realising solid performance improvement over conventional ZRPs in immersion and salt-spray chamber tests. Furthermore, the application of highly dispersed PDAPs at a content of 3.2 wt.% while PPy incorporated into zinc-rich hybrids at 0.16 wt.% is proposed to result in emerging additional functionalities increasing long-term anticorrosive performance of ZRPs by inhibiting sacrificial and self-corrosion of zinc and scavenging oxidative radicals thereby hindering oxidative degradation of the organic binder.     

光电光谱仪及其应用

光电光谱仪具有分析速度快、准确度高、可以同时测定若干元素以及操作简便等优点，广泛应用于机械、冶金等行业的金属材料化学成分分析。本文主要介绍了光电光谱仪的测量原理、基本结构及其在生产实际中的应用。     

Dilute-and-shoot procedure for the determination of mineral constituents in vinegar samples by axially viewed inductively coupled plasma optical emission spectrometry (ICP OES)

Samples of commercial wine vinegar were introduced in an axially viewed inductively coupled plasma optical emission spectrometry instrument (AX-ICP OES) equipped with different sample introduction systems: a cross-flow nebulizer combined with a double-path spray chamber (CF-DP) and cone spray associated with a cyclone spray chamber (CS-CC). Samples of white and red wine vinegar were diluted with water before analysis. Higher magnesium Mg II/Mg I ratios (11 and 10 for CS-CC and CF-DP, respectively) were obtained using a nebulization gas flow rate of 0.6 l min^-1 and an applied power of 1.3 kW. The background equivalent concentrations (BEC) and signal-to-background ratio (SBR) of analytes were improved using scandium (Sc) as the internal standard. The limits of detection (LOD) and limits of quantification (LOQ) for mineral constituents were similar for both introduction systems. Best recoveries values were obtained using a plasma under robust conditions, CS-CC system and Sc as the internal standard. The concentration determined in 13 commercial samples of wine vinegars varied between 0.2 and 3.0, between 0.02 and 0.4, between 8.5 and 100.0, between 0.01 and 0.05, between 27.0 and 540.0, between 4.0 and 79.0, between 0.4 and 10.0, and between 0.01 and 2.0 for aluminium (Al), barium (Ba), calcium (Ca), copper (Cu), potassium (K), magnesium (Mg), manganese (Mn), and zinc (Zn), respectively.