I2 Concentration Research Articles

Elaboration of a new Activated Carbon derived from the Crown of Oak (ACOW) to removal the toxic Iodine: Kinetic, Isotherms modelling and Thermodynamics Study

ABSTRACT The current study aims to develop a new adsorbent material using oak crown and explore its effectiveness in removing I2 ions through a series of batch experiments. ACOW was characterised by zero charge (pHpzc) and FTIR spectroscopy. The impact of the initial I2 concentration (20-100 mg/L), temperature (25-55 °C), pH (2-14), adsorbent dosage (2-10 g/L), Stirring speed (100-900 rpm), particle size (100-2000μm) and contact time (0-30 min) on I2 adsorption was examined. The adsorption kinetic obeys the pseudo-second order model with a determination coefficient (R2) equal to 0.999. Adsorption follows the Langmuir equation well, with the best fit to the experimental data at equilibrium. A qmax value (= 103.606 mg/g) at 25°C and 120.773 mg/g at 55°C were eliminated under the optimised conditions, indicating homogeneous adsorption on the surface of the adsorbent. The thermodynamic parameters gave a negative free energy ΔGo (-3.445 to -5.629 kJ/mol), a positive enthalpy ΔHo (18.406 kJ/mol) and an activation energy Ea (= 22.599 kJ/mol), thus confirming the spontaneous and endothermic nature of adsorption of iodine on ACOW. The positive entropy ΔSo (0.0733 kJ/mol K) show increased randomness of the solid-liquid interface during the adsorption.

Reaction mechanism of decomposition of phosphine-bridged Pd(I)-Pd(I) dimers into Pd(II) monomers by molecular iodine

Mechanistic studies on decomposition of Pd(I)-Pd(I) dimers via Pd(II)-Pd(II) intermediates into Pd(II) monomers were performed by the reaction of [Pd2I2(dppm)2] (1) (dppm = bis(diphenylphosphino)methane) and [Pd2(p3)2](BF4)2 (2) (p3 = bis(diphenylphosphinoethyl)phenylphosphine) with molecular iodine, where dppm and p3 are bridging “short-bite” bidentate and “regular-bite” tridentate phosphine ligands, respectively. It was previously reported that the decomposition rate constant for the Pd(II)-Pd(II) intermediate of 1, [Pd2I4(dppm)2], to give the monomeric [PdI2(dppm)] was independent of the I2 concentration under the pseudo-first-order conditions with excess I2. On the other hand, we have found that the decomposition was retarded by an addition of I2, which reduces the nucleophilicity and donating ability of the iodido ligand by association of I2 to give the I-–I2 interaction. The activation parameters of the decomposition with a large negative ΔS‡ value similar to substitution reactions of usual four-coordinate squarer-planar palladium(II) complexes suggested the associative intramolecular substitution mechanism. The oxidation of 2 to the Pd(II)-Pd(II) intermediate, [Pd2I2(p3)2]2+, and its decomposition into the monomeric [PdI(p3)]+ by I2 were also investigated kinetically and both reactions were also retarded with an increase in the I2 concentration. From the activation parameters of the intramolecular decomposition, it was indicated that the associative character was reduced because of breakdown of the sterically restricted framework. Such different properties in solution of 1 and 2 were applied complementarily to Heck-type C–C coupling reaction and dehalogenation reaction of aryl halide, respectively.

Multi-mode detection of iodine based on Au@Ag nanoparticle array with highly sensibility and stability using plasmonic surface lattice resonances

Designing a sensor to rapidly and simply detect iodine (I2) in liquid and gaseous phase with excellent sensitivity, high stability, and low cost at room temperature is highly desirable. Herein, a two-dimensional Au@Ag nanoparticle ordered array was prepared by template method combined with chemical reduction for detecting I2 at room temperature. Due to the ordered structure, a plasmonic surface lattice resonances (PSLR) peak appeared in extinction spectrum of the Au@Ag nanoparticle ordered array. When the ordered array exposed to I2, the Ag shell would react with I2 to form AgI, thus leading to a change in the dielectric medium surrounding the Au nanoparticles. This change would cause a variation of color and a shift of PSLR peak, realizing multi-mode detection of liquid and gaseous I2 at room temperature without any sophisticated instrument. With the increase of I2 concentration, the color of the Au@Ag nanoparticle array changed from red to yellow-green. Meantime, the PSLR peak displayed highly sensitive redshift with a larger offset (about 156 nm) and intense signal strength. Moreover, due to the ordered array structure, the PSLR peak possessed good uniformity and stability. Therefore, the PSLR peak was more suitable for detecting I2 in a large concentration region. Furthermore, the practical application of the present prepared Au@Ag nanoparticle array was explored by detecting gaseous I2 at room temperature. It was found that the Au@Ag nanoparticle array possessed high sensitivity to gaseous I2 with a detection limit reaching to trace level (1 ppb), suggesting tremendous potential for real-world application.

Effects of gas saturation and sparging on sonochemical oxidation activity under different liquid level and volume conditions in 300-kHz sonoreactors: Zeroth- and first-order reaction comparison using KI dosimetry and BPA degradation

The sonochemical oxidation activity was investigated for gas saturation and gas sparging under various liquid levels and volumes in 300 kHz sonoreactors. The liquid levels and volumes ranged from 5λ (25 mm, 0.47 L) to 50λ (250 mm, 4.30 L) and two gas mixtures, Ar:O2 (75:25) and N2:O2 (75:25), were used. Two types of reaction kinetics were observed to quantitatively analyze the sonochemical oxidation reactions: zero-order (KI dosimetry: C0 = 60.2 mM) and first-order (Bisphenol A (BPA) degradation: C0 = 0.043 mM). The masses of the sonochemical oxidation reactions were calculated and compared rather than the concentrations to more accurately compare the sonochemical oxidation activity under different liquid volume conditions. First, as the liquid level or volume increased for the zero-order reactions, the concentration of I3- ions representing the volume-averaged activity decreased substantially for gas saturation owing to the increase in liquid volume. However, gas sparging substantially enhanced sonochemical oxidation activity, and the mass of I3- ions representing the total activity remained constant as the liquid level increased from 20λ because of the improved liquid mixing and a shift in the sonochemical active zone. Second, as evidenced by the zero-order reactions, the concentration of BPA decreased considerably as the liquid level or volume increased in the first-order reactions. When gas sparging was used, higher reaction constants were obtained for both gas mixtures, ranging from 40λ to 50λ. However, a comparison of the sonochemical oxidation activity in terms of the degraded mass of BPA was inapplicable as the concentration of BPA decreased substantially and a lack of reactants occurred for the lower liquid level and volume conditions as the irradiation time elapsed. Instead, using the first-order reaction constant, a comparison of the required reaction times for a specific removal efficiency (30%, 60%, and 90%) was proposed. Gas sparging can substantially reduce the reaction time required for a liquid level of 40λ or higher.

Dye-sensitized solar cells with aluminum-doped zinc oxide nanoparticles-loaded electrolyte: A breakthrough solution for recombination and hysteresis suppression

Dye-sensitized solar cells (DSCs) suffer from reduced power conversion efficiency due to electron recombination with triiodide (I3−) ions at the photoanode/electrolyte interface. Organic additives are conventionally used in electrolyte to reduce recombination and improve the efficiency of the device. These additives react covalently with iodine (I2) in the electrolyte, leading to a reduction in the concentration of I3− ions. Other inorganic oxides, such as silica (SiO2), titania (TiO2), and magnesia (MgO), have been shown to improve the efficiency of the solar cell. These oxides can adsorb heavy ions to some extent. In this study, we investigated aluminum-doped zinc oxide nanoparticles (AZO NPs) as an inorganic additive with ionic adsorption properties towards I− and I3− anions in the electrolyte. We confirmed the ionic adsorption of AZO NPs through zeta potential and electrochemical impedance measurements. We observed a significant decrease in recombination between photogenerated electrons and electrolyte ions after adding AZO NPs, which resulted in an increase in open circuit voltage (VOC) and fill factor (FF) values. Furthermore, the incorporation of AZO NPs reduced the compelled hysteresis caused by the mismatch in current density-voltage curves for the forward and reverse scan direction. Mott-Schottky analysis confirmed the increase in VOC due to the negative shift in the Fermi level of the TiO2 photoanode. Additionally, open circuit voltage decay measurements indicated a longer electron lifetime at the TiO2/electrolyte interface in AZO NPs loaded electrolyte. Our findings suggest that AZO NPs have potential as an effective inorganic additive for improving the performance of DSCs.

Analytical Validation of Smartphone Spectroscopic Technic Used in an Educational Kinetic Study

Use of smartphone-based spectroscopy is showing a constant growth since last year. It presents the advantage of being widely available for everyone. The most important thing is that it is still a low-cost method adapted to the education context. However, as all analytical methods, it should be validated to ensure the reliability of its results. In this study, we present the steps of the validation process with its statistical tests applied to the dosage of di-iode. Shapiro–Wilk test revealed that our method has a random character. Homogeneity of variance analyses using the Cochran test confirmed the precision of the method. The Fisher test revealed the linearity of the model of correlation between I2 concentration and the response. The relation between response and concentration is A = 1000 C + 0.002. From the parameters of the linear regression of the model, we deduced the limits of quantification and XLq = 4·10−5 mol·L−1 and XLd = 1·10−5 mol·L−1. Thanks to tightness of the sample, the method of I2 dosage was successfully applied in iodine quantification to monitor acetone iodination during time in the context of kinetic studies with minimum system trouble. Being low cost, this method can facilitate access to physical methods in educational laboratories.

THAI experiments on iodine behavior in a room chain representing flow conditions in large containments

Iodine which can be released into the containment during a severe accident, is considered one of the most important nuclides with potential for public dose. Significantly different iodine concentrations can be expected in the individual compartments and rooms of large containments, due to geometrical constraints and the strong dependence of many iodine reactions on local thermohydraulic conditions. Such inhomogeneity may be relevant for organic iodide formation which depends on the concentration of deposited I2 and the dose rate.The objective of the two tests Iod-33 and Iod-35 was to measure the distribution of iodine along a convective flown-through room chain. This arrangement shall simulate the pathway of iodine from the locations of release (primary loop rupture) or formation (sump) along the plant rooms up to the dome of the containment and back. With respect to iodine, the aims were to measure the distribution and mixing of gaseous iodine in different rooms, the decrease of gaseous iodine by its deposition on painted surfaces, and the distribution of deposited iodine on the different painted surfaces.The two tests were performed in the two vessel THAI+ facility with additionally installed painted surfaces (painted with Gehopon epoxy paint) under superheated and condensing conditions. The main part of the painted surface area was provided in the form of painted steel sheets and arranged to form two intermediate floors within the THAI test vessel including small flow openings. Gaseous iodine was injected over several hours into the room chain in which a slow convection was established by means of differential wall heating.The gaseous I2 concentration inside the THAI+ facility increased continuously until the I2 injection was terminated. Simultaneously, the iodine deposition onto the painted surface increased. The gaseous I2 concentration decreased rapidly after stopping the I2 injection, in favor of a continuation of the I2 deposition on painted surfaces. The multi-compartment effect along the room chain has been demonstrated by the test results and the data allows for further development and validation of the I2/paint reaction model of severe accident codes.

Superior Iodine Uptake Capacity Enabled by an Open Metal-Sulfide Framework Composed of Three Types of Active Sites

Superior Iodine Uptake Capacity Enabled by an Open Metal-Sulfide Framework Composed of Three Types of Active Sites

Chemically Stable Guanidinium Covalent Organic Framework for the Efficient Capture of Low-Concentration Iodine at High Temperatures

The capture of radioactive I2 vapor from nuclear waste under industrial operating conditions remains a challenging task, as the practical industrial conditions of high temperature (≥150 °C) and low I2 concentration (∼150 ppmv) are unfavorable for I2 adsorption. We report a novel guanidinium-based covalent organic framework (COF), termed TGDM, which can efficiently capture I2 under industrial operating conditions. At 150 °C and 150 ppmv I2, TGDM exhibits an I2 uptake of ∼30 wt %, which is significantly higher than that of the industrial silver-based adsorbents such as Ag@MOR (17 wt %) currently used in the nuclear fuel reprocessing industry. Characterization and theoretical calculations indicate that among the multiple types of adsorption sites in TGDM, only ionic sites can bond to I2 through strong Coulomb interactions under harsh conditions. The abundant ionic groups of TGDM account for its superior I2 capture performance compared to various benchmark adsorbents. In addition, TGDM exhibits exceptionally high chemical and thermal stabilities that fully meet the requirements of practical radioactive I2 capture (high-temperature, humid, and acidic environment) and differentiate it from other ionic COFs. Furthermore, TGDM has excellent recyclability and low cost, which are unavailable for the current industrial silver-based adsorbents. These advantages make TGDM a promising candidate for capturing I2 vapor during nuclear fuel reprocessing. This strategy of incorporating chemically stable ionic guanidine moieties in COF would stimulate the development of new adsorbents for I2 capture and related applications.

Effect of suspension parameters towards the fabrication of BSCCO films by electrophoretic deposition

Superconductor Bi-Sr-Ca-Cu-O (BSCCO) thin films were fabricated on silver by electrophoretic deposition (EPD) method. By investigating the effects of solvents and I2 additives on the properties of suspension prepared of BSCCO powder, the particle charging mechanism is analyzed. Studying the effect of different solvents on the structure of BSCCO powder, isopropanol is the best dispersion solvent. Through the optimization of the I2 concentration, the results show that the optimal concentration of I2 is 0.08 mg ml−1. The processing parameters critically influencing the morphology of BSCCO films are identified and optimized to obtain uniform films with high packing density of BSCCO particles. After heated at 820 °C for 20 h, the smoothest surface morphology, high c-axis orientation, and highest critical temperature(Tc) of 82 K are obtained from the film prepared with optimized suspension.

Electrochemical enhancement of high-efficiency wet removal of mercury from flue gas

Electrochemical wet absorption composite system has an excellent potential to remove Hg0 from flue gas. In this study, ruthenium iridium titanium platinum quaternary composite electrode is used as an anode and titanium electrode is used as the cathode, and KI/I2 absorption solution is introduced into the electrocatalysis system as an electrolyte to form KI/I2 electrochemical catalytic oxidation system. The removal rate of Hg0 in flue gas can be increased to 92.3%. The effects of electrolytic voltage, current, Pt content, I2 concentration, and the ratio of KI/I2 on the removal of Hg0 were discussed. The possible free radicals in the electrochemical cathode, anode, and solution were characterized and tested by XRD, SEM, UV-Vis (detection of H2O2, ·OH, O3), and FTIR (detection of IO3-). Combined with experimental data and theoretical derivation, the mechanism of Hg0 removal from flue gas by electrochemical catalytic oxidation alloy formation wet absorption combined process was studied. The results show that the combined process, which is a promising technology can not only improve the removal efficiency of Hg0, but also realize the resource recovery of Hg0 and I2, and provide a feasibility study for the subsequent regeneration of KI/I2 absorption solution.

Electrolyte Tuning in Iron(II)-Based Dye-Sensitized Solar Cells: Different Ionic Liquids and I2 Concentrations.

The effects of different I2 concentrations and different ionic liquids (ILs) in the electrolyte on the performances of dye-sensitized solar cells (DSCs) containing an iron(II) N-heterocyclic carbene dye and containing the I–/I3– redox shuttle have been investigated. Either no I2 was added to the electrolyte, or the initial I2 concentrations were 0.02, 0.05, 0.10, and 0.20 M. The short-circuit current density (JSC), open-circuit voltage (VOC), and the fill factor (ff) were influenced by changes in the I2 concentration for all the ILs. For 1-hexyl-3-methylimidazole iodide (HMII), low VOC and low ff values led to poor DSC performances. Electrochemical impedance spectroscopy (EIS) showed the causes to be increased electrolyte diffusion resistance and charge transfer resistance at the counter electrode. DSCs containing 1,3-dimethylimidazole iodide (DMII) and 1-ethyl-3-methylimidazole iodide (EMII) showed the highest JSC values when 0.10 M I2 was present initially. Short alkyl substituents (Me and Et) were more beneficial than longer chains. The lowest values of the transport resistance in the photoanode semiconductor were found for DMII, EMII, and 1-propyl-2,3-dimethylimidazole iodide (PDMII) when no I2 was added to the initial electrolyte, or when [I2] was less than 0.05 M. Higher [I2] led to decreases in the diffusion resistance in the electrolyte and the counter electrode resistance. The electron lifetime and diffusion length depended upon the [I2]. Overall, DMII was the most beneficial IL. A combination of DMII and 0.1 M I2 in the electrolyte produced the best performing DSCs with an average maximum photoconversion efficiency of 0.65% for a series of fully-masked cells.

Binary Redox Couples for Highly Transparent and High-Voltage Dye-Sensitized Solar Cells

The conventional iodine-based (I−/I3 −) electrolyte used in dye-sensitized solar cells (DSSCs) presents several limitations, such as ∼30% absorption of visible light in the wavelength range of 300–500 nm and a large potential difference between the Fermi level of I−/I3 − and the HOMO level of the dye. This has a negative impact on the characteristics of DSSC such as transparency and open circuit voltage (Voc). In the present work, a series of transparent electrolytes are prepared using various additives such as I2, LiI, guanidine thiocyanate/guanidine nitrate (GuSCN/GuNO3), and Br2 to obtain highly transparent and high voltage DSSCs. The results demonstrate that the usage of the optimized electrolyte consisting of 0.003 M Br2, 0.01 M LiI, and 0.1 M GuNO3, with the binary redox couple (I−, Br−)/(I3 −, I2Br−), contributes to an ∼25% increase in transmittance compared to that of the conventional electrolyte, while the concentration of I3 − is significantly reduced. Furthermore, the downward shift in the Fermi level of the binary redox system is shown to provide an ∼100 mV enhancement in the Voc of the DSSC compared with that of the conventional electrolyte based DSSC. In addition, the devices with the optimized binary redox system achieve a power conversion efficiency of ∼7.94% which is closely comparable to the performance of conventional (I−/I3 −) electrolyte-based DSSCs. Thus, the present study could provide immense insights toward the fabrication of high-voltage and transparent DSSCs for the application in transparent photovoltaic windows. Furthermore, by using a binary redox electrolyte, the DSSCs that operative under a 2000 lux compact fluorescent lamp (CFL) were also successfully fabricated and yielded a promising efficiency of 23.6%.

Kinetic Investigation of Pd(II)-Catalyzed Ortho C-H Iodination of Benzamide with I2

Abstract Intimate kinetic investigation of Pd(II)-catalyzed ortho C-H iodination of benzamide substrate via cyclopalladation was performed for the first time by using molecular I2 as a sole oxidant and acetate as a base. The reaction rate of the cyclopalladation step is independent of benzamide concentration but increased with an increase in acetate concentration and then gradually decreased due to blocking on coordination sites of Pd(II) by acetate. On the other hand, the reaction rate of the subsequent iodination step was first-order with respect to I2 concentration. Though the total activation energies of the cyclopalladation and iodination processes are comparable, it is reasonable that the cyclopalladation appears to be the rate-determining step of Pd(II)-catalyzed ortho C-H iodination, in which substrates, I2, and acetate are used in large excess. From the present results, it can be proposed that a minimum amount of acetate required for deprotonation of amide and ortho proton for cyclopalladation and rather excess I2 should be used to provide acceleration and high performance of Pd(II)-catalyzed ortho C-H iodination.

Iodine adsorption characteristics of activated carbon obtained from Spinacia Oleracea (spinach) leaves

Spinach leaves powder was modified by activation with conc. H2SO4 and was characterized by using FTIR, optical microscopy, XRD analysis and methylene blue adsorption method. The maximum specific surface area measured by the Methylene blue adsorption method was 499 m2/g. The adsorption of iodine was investigated by varying parameters as pH, adsorbent dose, contact time and I2 concentration. The adsorption process was fitted to the Langmuir model controlled by pseudo - second – order kinetics with a constant rate value of 0.00305 g/(mg·min). The maximum adsorption was at pH 10. The maximum adsorption capacity was 909.091 mg/g. The ∆G value was -25 kJ/mole, which confirmed the physico - chemcal adsorption process.

Development of Ag/CNT Films As Electrical Connectors Using a Cyanide-Free Electroplating Bath

Ag films as an electrical contact material have been applied to electrical devices because of the best electrical conductivity and is relatively low cost compared to that of Au. However, Ag is easily sulfurized in the air. In addition, Ag connectors with extremely soft are easy to wear. These are responsible for the increasing in resistance between electrical connectors. To overcome these issues, Ag/graphite1 with wear resistant property and Ag/CNTs2,3 with excellent mechanical strength have been studied. In the later composite, CNTs function as electrical pass even in the degradation derived from sulfidation and friction. This is the motivation of the development of Ag composite as a connector. The Ag/CNT composites have been prepared by using toxic cyanide electroplating baths4-6 which suppress dendrite growth of Ag by stable complex with cyanide ions. We focused on the iodide aqueous solutions instead of toxic cyanide electroplating baths for realizing eco-friendly approach. In the present study, the pH effect in iodide aqueous solutions on current efficiency of Ag electroplating was investigated. Then, we tried to produce Ag/CNT composite with high electrical contact properties and remarkable wear resistance. The pH in iodide-electroplating solutions was adjusted using H2SO4 or KOH. CNTs (VGCF, SHOWA DENKO K.K.) were used without further purification, and then the CNTs were dispersed into the iodide-electroplating solutions. Co-electrodeposition of Ag/CNT was performed under galvanostatic conditions using a pure Ag plate as the anode and a pure Cu plate as the cathode at temperature of 298 K. The concentration of I3 − causing poor current efficiency during the electroplating was determined by iodometric titration of I2 (I3 − ⇄ I− + I2) using Na2S2O3-dissolved aqueous solution (I2 + 2S2O3 2− → S4O6 2− + 2I−).7 Under the condition of low pH at atmosphere, I− is generally oxidized to I2, and then the I2 reacts with I− to form I3 − (I2 + I− ⇄ I3 −). Considering the equilibrium potentials of Ag+/Ag = +0.799 V vs. SHE and I3 −/I− = +0.536 V vs. SHE, the reduction of Ag+ (Ag electrodeposition) proceeds preferentially. However, at the presence of [Ag m I n ] m − n complex ions with a relatively high stability constant, the equilibrium potential of Ag+/Ag shifts to negative and thereby consumes electrons (currents) by the reduction of I3 − during the electroplating. Therefore, the I3 − formation should be suppressed. In the solution adjusted to pH=1, the I3 − concentration was suddenly increased, whereas in the solution of pH=12, the concentration was maintained below detection limit even after 30 days (Fig. 1a). The current efficiency was significantly improved, and 100% efficiency was achieved only when adjusting to pH=12. In the composite electroplating-film prepared using the solution (pH=12), we can clearly observe that CNTs are uniformly immobilized by Ag film and incorporated inside the film (Fig. 1b). The structure with large amount of CNTs should offer not only the high electrical contact property but also the improved wear resistance.References) 1. W. Lv, T. S. Chen, K. Q. Zheng, Z. G. Zhang, Werkst. Korros., 69, 933 (2018). 2. Y. Litovka, I. Dyakov, R. Stolyarov, V. Kulakov, A. Zhigachev, V, Korenkov, Mater. Sci. Eng., 693, 012005 (2019). 3. M. Fujishige, M. Sekino, K. Fujisawa, S. Morimoto, K. Takeuchi, S. Arai, A. Kawai, Appl. Phys. Express, 3, 065801 (2010). 4. V. I. Rigou, G. Marginean, D. Frunzăverde, C. V. Câmpian, Wear, 290, 61 (2012). 5. I. Krastev, T. Valkova, A. Zielonka, J. Appl. Electrochem., 34, 79 (2004). 6. Y. Zhou, Y. Huo, J. Mater. Sci. Mater. Electron., 27, 931 (2016). 7. W. Gottardi, J. Pfleiderer, Anal. Bioanal. Chem., 382, 1328 (2005). Figure 1

Comparative analysis of I2-KI and HNO3 leaching in a life cycle perspective: Towards sustainable recycling of end-of-life c-Si PV panel

An iodine-iodide system was investigated as an alternative lixiviant for HNO3 for leaching precious metals from the end-of-life c-Si photovoltaic (PV) cell. A series of batch experiments were conducted for the optimization of leaching kinetics and thermodynamic equilibrium followed by a life cycle assessment (LCA) using data from the experiments. The results showed that more than 95% of Ag and Al leached out within the first 5 min. The optimum conditions for equilibrium leaching were as follows: solid to liquid ratio of 1:10 for Ag (1:9 ml for Al), and I2 concentration of 0.35 M for Ag (0.3 M for Al), with I- concentration of 0.7 M. In addition, selective leaching of Ag could also be accomplished by adjusting the reaction pH to 9.6%, and 93% of reproducibility was achieved via the rejuvenation of the exhausted leaching solution, which can benefit the subsequent recovery process. The leaching efficiency of iodine-iodide system was nearly comparable to that of HNO3, and the environmental impacts of the two cycle of continuous process with rejuvenation of the iodine leaching solution can be effectively reduced especially in the acidification & eutrophication, respiratory effect, and mineral extraction categories with subsequent exclusion of the additional neutralization process.

Capture of I131 from medical-based wastewater using the highly effective and recyclable adsorbent of g-C3N4 assembled with Mg-Co-Al-layered double hydroxide

This paper reports a very high capacity and recyclable Mg-Co-Al-layered double hydroxide@ g-C3N4 nanocomposite as the new adsorbent for remediation of radioisotope-containing medical-based solutions. In this work, a convenient solvothermal method was employed to synthesize a new nano-adsorbent, whose features were determined by energy dispersive X-ray (EDS/EDX), XRD, FESEM, TEM, TGA, BET, and FT-IR spectroscopy. The as-prepared nano-adsorbent was applied to capture the radioisotope iodine-131 mainly from the medical-based wastewater under different conditions of main influential parameters, (i.e. adsorbent dose, initial I2 concentration, sonication time, and temperature). The process was evaluated by three models of RSM, CCD-ANFIS, and CCD-GRNN. Furthermore, comprehensive kinetic, isotherm, thermodynamic, reusability cycles and optimization (by GA and DF) studies were conducted to evaluate the behavior and adsorption mechanism of I2 on the surface of Mg-Co-Al-LDH@ g-C3N4 nanocomposite. High removal efficiency (95.25%) of 131I in only 30 min (i.e. during 1/384 its half-life), along with an excellent capacity that has ever been reported (2200.70 mg/g) and recyclability (seven times without breakthrough in the efficiency), turns the nanocomposite to a very promising option in remediation of 131I-containing solutions. Besides, from the models studied, ANFIS described the process with the highest accuracy and reliability with R2 > 0.999.

Red raspberry (Rubus idaeus) consumption restores the impaired vasoconstriction and vasorelaxation response in the aorta of the obese Zucker rat, a model of the Metabolic Syndrome

Metabolic Syndrome (MetS) increases the risk of cardiovascular disease. Whole red raspberry (WRR) consumption on vascular function was investigated in the obese Zucker rat (OZR), model of MetS. Male OZR and their lean littermates (LZR) were placed on a control (C) or an 8% w/w WRR-enriched diet for 8 weeks. Phenylephrine (Phe)-induced vasoconstriction and acetylcholine (Ach)-induced vasorelaxation were measured in aortic rings in the presence or absence of L-N-monomethyl-arginine (L-NMMA) and mefenamic acid (MFA). Phe-induced vasoconstriction was lower in the OZR-C compared to LZR-C (p < 0.05). The WRR diet partially restored aortic response in the OZR-WRR aorta (p < 0.05) compared to OZR- C. The OZR-WRR group pre-treated with L-NMMA increased compared to OZR-C (p < 0.05). Pre-treatment with L-NMMA, maximal relaxation response was higher in the OZR compared to the LZR (p < 0.05). With L-NMMA, maximal relaxation response in OZR-WRR (p < 0.05) was lower compared to the OZR-C. Prostacyclin I2 concentration was higher in the OZR compared to the LZR (p < 0.05) and was attenuated in the OZR-WRR (p < 0.05). Aortic expression of eNOS and COX-2 were downregulated in the OZR-WRR (p < 0.05). In conclusion, WRR restores the impaired vascular tone of the OZR by enhancing Phe-induced vasoconstriction and attenuating Ach-induced vasorelaxation.

Electrophoretic deposition of trimanganese tetraoxide coatings on Ni-coated SUS 430 steel interconnect

A uniform trimanganese tetraoxide (Mn3O4) coating has been prepared on Ni-coated SUS 430 steel by novel electrophoretic deposition (EPD) approach based on stable Mn3O4 suspension which has been achieved in ethanol medium with iodine (I2) as dispersant. Different suspension characteristics and deposition kinetics have been systematically studied to optimize the suspension chemistry and deposition process parameters. The suitable EPD conditions including the current density (1 mA cm−2), deposition time (10 s) and I2 concentration (1.2 g L−1) are applied to deposit uniform nano-Mn3O4 coating. It is also revealed that the deposited mass and the thickness of Mn3O4 coatings can be controlled by adjusting the EPD process parameters. The Mn2O3/(Mn,Cr)3O4/Cr2O3 oxide is formed via oxidizing the coated SUS 430 stainless steel and no Cr-containing species migrates outwards.