Effect Of Iodine Concentration Research Articles

Effect of iodine concentration on growth, iodine uptake and antioxidant activity of lettuce (Lactuca sativa L.) biofortified with iodine in nutrient film technique hydroponic system

Effect of iodine concentration on growth, iodine uptake and antioxidant activity of lettuce (Lactuca sativa L.) biofortified with iodine in nutrient film technique hydroponic system

Effect of iodine concentration and body size on iodine subtraction in virtual non-contrast imaging: A phantom study

IntroductionDual-energy computed tomography (DECT) can generate virtual non-contrast (VNC) images. Herein, we sought to improve the accuracy of VNC images by identifying the optimal slope of contrast media (SCM) for VNC-image generation based on the iodine concentration and subject's body size. MethodsWe used DECT to scan a multi-energy phantom including four iodine concentration rods (15, 10, 5, and 2 mg/mL), and 240 VNC images (eight SCM ranging from 0.49 to 0.56 × three body sizes × ten scans) that were generated by three-material decomposition. The CT number of each iodine and solid water rod part was measured in each VNC image. The difference in the CT number between the iodine and the solid water rod part was calculated and compared using paired t-test or repeated measures ANOVA. ResultsThe SCM that achieved an absolute value of the difference in CT number of <5.0 Hounsfield units (HU) for all body sizes simultaneously was greater at lower iodine concentration (SCM of 0.5, 0.51, and 0.53 at 10, 5, and 2 mg/mL iodine, respectively). At an iodine concentration of 15 mg/mL, no SCM achieved an absolute difference of <5.0 HU in CT number for all body sizes simultaneously. At all iodine concentrations, the SCM achieving the minimal difference in the CT number increased with the increase in body size. ConclusionBy adjusting the SCM according to the iodine concentration and body size, it is possible to generate VNC images with an accuracy of <5.0 HU. Implications for practiceImproving the accuracy of VNC images minimizing incomplete iodine subtraction would make it possible to replace true non-contrast (TNC) images with VNC images and reduce the radiation dose.

Immobilization of silver-coated silica gel with varying iodine loading in silicate glass ceramics

In this study, we fabricated silicate glass ceramics using a mixture of oxides containing SiO2, B2O3, Bi2O3, and ZnO, to immobilize iodine adsorbed by silver-coated silica gels. The effects of SiO2 content on quaternary glass were explored by changing the molar ratio of SiO2 in the sintered matrix. The curing substrate with the highest amorphous index (0.6) was selected to simulate the immobilization of silver-coated silica gel loaded with 10, 20, 30, 40, and 50wt% iodine. Further, the effects of iodine concentration on the sintered matrix were analyzed based on phase structure and microstructure. The amorphous degree of sintered silicate matrix declines with increasing iodine loading in silver-coated silica gel. Transmission electron microscopy (TEM) results detected that a sample loaded with 20wt% iodine and sintered at 550 °C showed a polycrystalline glass-ceramic phase.

Highly transparent and conductive γ-CuI films grown by simply dipping copper films into iodine solution

In this Letter, we demonstrate a simple and environmentally friendly method to grow large-area p-type conductive CuI films by dipping copper films into ethanol solution of iodine at room temperature. The effects of iodine concentration and film thickness on the morphologies, crystalline phases, optical and electrical properties of CuI films were investigated. All the films are γ-CuI with preferential (111) orientation. At the optimized growth condition, the CuI films exhibit a high transmission which exceeds 73% in the visible spectral range and low resistivity of 0.02 Ω cm. These results pave the way for the growth and further application of large-area CuI films in optoelectronic devices.

Suspension chemistry and electrophoretic deposition of YSZ-NiO nano-composite films on an iron-nickel based superalloy

Suspensions of mixed YSZ (3 mol%) and Ni particles in acetylacetone medium were prepared using iodine as a dispersant. The effect of iodine concentration on suspension stability, particle size distribution and zeta potential of suspensions were studied to optimize the suspension chemistry. Electrophoretic deposition (EPD) method was applied for the preparation of green form YSZ/Ni nano-composite coating with suspension of YSZ and Ni particles in acetylacetone in presence of 0.2 g/l iodine. Based on the derived results, both applied voltage of 7 V and deposition time of 4 min are suitable for deposition of green composite coating. After deposition, green form coatings were heat treated at 500 °C for 1 h for oxidation of nickel particles and further sintered at 1100 °C for 4 h in the air. For the first time, the reaction bonding process along with the sintering heat treatment were studied and developed to fabricate uniform, crack-free and dense YSZ/NiO coatings. The volume shrinkage of the coating was compensated by the volume expansion, caused by oxidation of nickel in the green coatings. Also, addition of Ni particles to YSZ lowered the sintering temperature of the coating about 300 °C, since sintering temperature of the pure YSZ is 1400 °C but after addition of nickel the coating was sintered at 1100 °C. The coating adhesion to substrate was evaluated using ASTM D3359 and Rockwell C indentation (VDI 3398) methods. The result of adhesion tests showed that the coatings have good adhesion strength (5B according to ASTM D3359B).

Enhanced electrical conductivity of alumina/nano-carbon ceramic composite via iodine impregnation of gel-casted alumina body and reductive sintering

In this work, we present the fabrication of alumina/nano-carbon ceramic composite displaying enhanced electrical conductivity through facile iodine impregnation of gel-casted alumina body. Following the previously developed novel fabrication process of alumina/nano-carbon composite having a highly uniform nano-carbon network and superior semi-conductive properties via reductive sintering of gel-casted alumina body under inert atmosphere, we extended the process through the facile impregnation of gel-casted body in iodine solution resulting in enhancement of the amount of nano-carbon, graphitization degree, electrical conductivity and carrier density. The effect of iodine concentration on the properties of alumina/nano-carbon as well as the mechanism for enhanced electrical performance are also systematically investigated.

Electrophoretic Deposition Kinetics and Characterization of Ni–La1.95Ca0.05Zr2O7−δ Particulate Thin Films

Suspensions of NiO–La1.95Ca0.05Zr2O7−δ (NiO–LCZ) composite material have been prepared in isopropanol medium using iodine and acetylacetone as dispersants. The effect of iodine concentration on suspension stability, electrical conductivity, and suspension pH are studied in detail to optimize the suspension chemistry. Electrophoretic deposition has been successfully conducted on conducting substrate (steel plate) to fabricate NiO–LCZ thin particulate films. Deposition kinetics have been studied in detail to optimize the process parameters. Good quality particulate films of such composite on steel plates are obtained at an applied voltage of 60 V for 3 min. The optimized suspension chemistry and process parameters thus obtained are then used to fabricate NiO–LCZ composite films onto nonconducting porous ceramic substrate by placing a conducting plate at the reverse side of the porous substrate. The deposited films along with the ceramic substrates are co‐fired at 1400°C for 6 h in reducing atmosphere (5% hydrogen in argon) to produce a good quality dense Ni–LCZ film of thickness ~40 μm. The hydrogen permeation flux of the developed cermet membrane has been measured and it reveals that Ni–LCZ could be used as a potential membrane for hydrogen separation at high temperature.

Effect of Iodine Concentration in the Quasi-Solid State Electrolyte on the Photovoltaic Performance of Dye-Sensitized Solar Cells

In the present study, the effect of iodine concentration on the photovoltaic properties of dye sensitized solar cells (DSSCs) based on the quasi-solid state electrolyte has been investigated. The electron transport properties and interfacial recombination kinetics have been evaluated by electrochemical impedance spectroscopy (EIS). It is found that increasing the concentration of iodine decreases the open-circuit voltage (Voc) whereas short circuit current density (Jsc) and fill factor (FF) shows improvement. The increment in Jsc for 0.05 M I2 concentration is ascribed to the decreased charge transfer resistance value obtained by EIS analysis. In addition increasing the concentration of I2 decreases the Voc which is attributed to the increased recombination with tri-iodide ions (I3−) as verified from the EIS analysis under dark condition.

In situ thermal polymerization of an ionic liquid monomer for quasi‐solid‐state dye‐sensitized solar cells

ABSTRACTIn situ thermal polymerization of a model ionic liquid monomer and ionic liquids mixture to form gel electrolytes is developed for quasi‐solid‐state dye‐sensitized solar cells (Q‐DSSCs). The chemical structures and thermal property of the monomers and polymer are investigated in detail. The effect of iodine concentration on the conductivity and triiodide diffusion of the gel electrolytes is also investigated in detail. The conductivity and triiodide diffusion of the gel electrolytes increase with the increasing I2 concentration, while excessive I2 contents will decrease the electrical performances. Based on the in situ thermal polymeric gel electrolytes for Q‐DSSCs, highest power conversion efficiency of 5.01% has been obtained. The superior long‐term stability of fabricated DSSCs indicates that the cells based on in situ thermal polymeric gel electrolytes can overcome the drawbacks of the volatile liquid electrolyte. These results offer us a feasible method to explore new gel electrolytes for high‐performance Q‐DSSCs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42802.

Evaluation of contrast enhancement and image quality:a comparison between different tube voltages and iodine concentrations in abdominal dynamic CT scans in minipigs

Objective To investigate the effect of tube voltage and iodine concentration of contrast medium (CM) on abdominal dynamic enhanced CT image quality. Methods Six miniature pigs underwent repeated upper abdomen dynamic contrast-enhanced CT scans in 4 scanning protocols with different concentration of CM and tube voltage, namely, protocol 1, CM with iodine concentration of 270 milligrams iodine per milliliter (mg/ml) and 80 kV tube voltage; protocol 2, 270 mg/ml and 120 kV; protocol 3, 370 mg/ml and 80 kV and protocol 4, 370 mg/ml and 120 kV. The same iodine dose (600 mg/ml) and iodine delivery rate (IDR) (920 mg/s) were used in all protocols. The CM with iodine concentration of 270 mg/ml were injected at a flow rate of 3.4 ml/s, and 370 mg/ml CM injected at 2.5 ml/s. Image reconstruction was performed with iterative reconstruction (iDose4) in protocol 1 and 3,filtered back projection (FBP) was used in protocol 2 and 4. A subjective scoring system for image quality, image noise and sharpness was conducted by 2 radiologists independently. The measured values (peak of enhanced CT values, image noise of aorta, inferior vena cava, portal vein, hepatic vein and liver parenchyma) as well as the calculated values [their time-to-peak, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios] were compared between among 4 protocols. The CT volume dose index (CDTIvol) and dose length product (DLP) were recorded from the CT console after each scanning. Factorial designed ANOVA was used for comparison of enhanced CT values of vessels and liver parenchyma, noise, SNR and CNR. The Kruskal-Wallis test was used for comparison of values among the 4 protocols, including the time-to-peak enhancement of vessels and liver parenchyma, the subjective scores of image quality indices. Result There was no significant differences in subjective scores of the image quality, image noise and image sharpness (P>0.05). The scored were more than 3, and the images with 4 scanning protocols were all acceptable for diagnosis. There was no significant differences between protocol 1 and 3, protocol 2 and 4 in the peak enhancement CT values of aorta [(729±46) HU vs.(707±59)HU,(515±84)HU vs. (513±53)HU], inferior vena cava [(366±95)HU vs. (368±92)HU, (282±39)HU vs. (262 ± 67)HU], portal vein [(213 ± 18)HU vs.(201 ± 29)HU, (180 ± 21)HU vs. (176 ± 27)HU], hepatic vein[(207±18)HU vs. (193±10)HU, (179±24)HU vs. (170±14)HU] and liver parenchyma [(128±7) HU vs. (127±4) HU,(135±5)HU vs.(135±6)HU] (P>0.05). But the CT values of vessels (aorta, inferior vena cava, portal vein and hepatic vein) in protocol 1 and 3 were significantly higher than those in protocol 2 and 4 (P 0.05). No significant differences were observed on the peak times, SNR and CNR in aorta, inferior vena cava, portal vein, hepatic vein and liver parenchyma among 4 protocols (P>0.05). The CDTIvol and DLP! were 199.67 mGy, 1 597.4 mGy·cm respectively in protocol 1 and 3,585.12 mGy and 4 680.9 mGy·cm in protocol 2 and 4 (scanning with 120 kV). Conclusions CM with different iodinated concentration could achieve the same enhancement in the abdominal vessels and liver parenchyma by using the proper scan protocols, which have the same IDR and iodine dose per kilogram body weight.Higher vessel enhanced peak values were achieved when using the protocols with 80 kV tube voltage than 120 kV. By using a low dose protocol of 80 kV tube voltage with the iterative reconstruction algorithm, the quality of image can be warranted. Key words: Tomography, X-ray computed; Contrast media; Radiation dosage

Effect of Iodine Concentration in MWCNTs for MEH-PPV Based Organic Solar Cell Applications

In general, Iodine doping concentration can affect the conductivity of the CNTs and explicitly the efficiency of organic solar cells. Iodine is a p-type dopant and when doped into MWCNTs it form an electron acceptor in the form of (I3)- or (I5)-. Therefore, electron transfer from Iodine to MWCNTs can generate free hole carriers. This free hole carriers is then collected by the electrodes. However, the generated free carriers depend on the concentration Iodine being used. It can be seen that as the concentration of Iodine increase from undope, 40 mg, 60 mg and 1 g, the I-MWCNTs are well dispersed in the polymer matrix. The results obtained reveal that the films are smooth as the concentration of Iodine increased. This shows that the agglomerations of the CNTs are less when there is more Iodine being doped with the CNTs. It can also be observed that as the Iodine concentration increased the film thickness decreased. In this work, the possibility to get efficiency with thickness of less than 60 nm is proved and the obtained efficiency with thickness about 51 nm at 1 g Iodine doping has been recorded with 8.01 x 10-4 %.

Acetylation of banana (Musa paradisiaca L.) and corn (Zea mays L.) starches using a microwave heating procedure and iodine as catalyst: II. Rheological and structural studies

The effect of iodine concentration on the acetylation of starches with low and moderate degree of substitution (DS<0.5) and its impact on the physicochemical feature and structural features was evaluated. The acetylated starches were prepared with 0.03mol anhydroglucose unit, 0.12mol of anhydride acetic, and 0.6, 0.9 or 1.4mM of molecular iodine as catalyst in a sealed Teflon vessel using microwave heating (600W/2min). Pasting profile and rheological properties were obtained under steady flow; dynamic oscillatory test was used. Structural features were obtained by HPSEC-RI. In acetylated starches, DS and acetyl groups increased when the iodine concentration increased, corn starch showed higher values than banana starch. The viscosity of acetylated starches decreased relative to unmodified starches while, acetylated corn starch had lower value than acetylated banana starch. In the flow curves, a non-Newtonian pattern (shear-thinning) was shown in the pastes of native and modified starches. Storage modulus (G’) and loss modulus (G”) showed low dependence on frequency (G’αω0.1; G”αω0.2) on frequency sweep test, which is characteristic of a viscoelastic gel. Debranched native banana and corn starches presented trimodal chain-length distribution. The pattern was maintained in the acetylated starches, but with different level of short and long chains. The structural differences in native and acetylated samples explain the rheological characteristics in both starches.

Effect of iodine concentration on the photovoltaic properties of dye sensitized solar cells for various I2/LiI ratios

In the present study, the effect of iodine concentration on the photovoltaic properties of dye sensitized solar cells (DSSC) based on TiO2 nanoparticles for three different ratios of lithium iodide (LiI) and iodine (I2) has been investigated. The electron transport properties and interfacial recombination kinetics have been evaluated by electrochemical impedance spectroscopy (EIS). It is found that increasing the concentration of lithium iodide for all ratios of iodine and lithium iodide decreases the open-circuit voltage (Voc) whereas short circuit current density (Jsc) and fill factor (FF) shows improvement. The reduction in Voc and increment in Jsc is ascribed to the higher concentration of absorptive Li+ cations which shifts the conduction band edge of TiO2 positively. The increase in FF is due to the reduction in electron transport resistance (Rω) of the cell. In addition for all the ratios of LiI/I2 increasing the concentration of I2 decreases the Voc which is attributed to the increased recombination with tri-iodide ions (I3−) as verified from the low recombination resistance (Rk) and electron lifetime (τ) values obtained by EIS analysis.

Influence of iodine concentration on the photoelectrochemical performance of dye-sensitized solar cells containing non-volatile electrolyte

The effect of iodine concentration in the electrolyte with non-volatile solvent of dye-sensitized solar cells (DSCs) on photovoltaic performance was studied. The electron transport and interfacial recombination kinetics were also systematically investigated by electron impedance spectroscopy (EIS). With the iodine concentration increased from 0.025 to 0.1 M, open-circuit voltage ( V oc) and photocurrent density ( J sc) decreased while fill factor ( ff) increased significantly. The decline of the V oc and J sc was mainly ascribed to increased electron recombination with tri-iodide ions (I 3 −). The increased fill factor was primarily brought by a decrease in the total resistance. From impedance spectra of the solar cells, it can be concluded that increasing the iodine concentration in electrolytes could decrease charge transfer resistance ( R ct) and the chemical capacitance ( C μ), increase the electron transport resistance ( R t), and hence decrease the electron lifetime ( τ) and the effective diffusion coefficient ( D n) of electrons in the TiO 2 semiconductor. With optimum iodine concentration, device showed a photocurrent density of 16.19 mA cm −2, an open-circuit voltage of 0.765 V, a fill factor of 0.66, and an overall photo-energy conversion efficiency of 8.15% at standard AM 1.5 simulated sunlight (100 mW cm −2).

Intravenous Contrast Material Administration at Helical 16–Detector Row CT Coronary Angiography: Effect of Iodine Concentration on Vascular Attenuation

The institutional review board approved this study, and all patients gave written informed consent. One hundred twenty-five patients scheduled to undergo retrospectively electrocardiographically gated 16-detector row computed tomographic coronary angiography were prospectively randomized into the following five groups with respect to the intravenous administration of a 140-mL bolus of contrast material at 4 mL/sec: group 1 (iohexol [300 mg of iodine per milliliter]), group 2 (iodixanol [320 mg I/mL]), group 3 (iohexol [350 mg I/mL]), group 4 (iomeprol [350 mg I/mL]), and group 5 (iomeprol [400 mg I/mL]). Attenuation was measured in the descending aorta and coronary arteries. One-way analysis of variance was used to compare groups. Mean attenuation values in the descending aorta were significantly (P < .05) lower in group 1 and higher in group 5 compared with the mean values in the other three groups. The same pattern was observed in the coronary arteries. Contrast materials with higher iodine concentrations yield significantly higher attenuation in the descending aorta and coronary arteries.

Investigation of 2 liquid phase separation characteristics on the iodine–sulfur thermochemical hydrogen production process

Separation characteristics of 2 liquid phase, sulfuric acid phase and poly-hydriodic acid phase, in HI-H 2SO 4-I 2 solution of the iodine–sulfur (IS) thermochemical hydrogen production process were measured in the wide operation temperature range, from 273 to 368 K in order to establish the closed-cycle operation technology and to improve thermal efficiency of the process. The effects of solution temperature and composition of initial solution on the separation characteristics were investigated. The effect of iodine concentration in the solution on the separation characteristics was also evaluated. The separation characteristics were found to improve with the increase in iodine concentration. Iodine concentration at the point where the solution starts to separate and at the point that iodine saturates, were determined by using measured data.

Low-frequency electrical conductivity of poly(phenylacetylene)-iodine in tetrahydrofuran solutions: effect of iodine concentration

The electrical conductivity of poly(phenylacetylene)-iodine in tetrahydrofuran solution has been measured at the frequency of 10 kHz, in the temperature range from −15 to 40 °C as a function of iodine concentration. The data have been analysed on the basis of the counterion fluctuation model developed for highly charged polyelectrolyte aqueous solutions. The dependence of the electrical conductivity on the iodine concentration suggests that the conduction mechanism is governed by the interaction of the polymer with iodine molecules, resulting in a charge-transfer complex in solution, the effectiveness of which is maximum at some well-defined concentrations corresponding to six polymer units for each I 5 − ion.

Preparation and purification of dimethylzinc and the effect of iodine doping on the opto-electronic properties of epitaxial ZnSe layers grown by metalorganic chemical vapour deposition

The effect of iodine concentration in dimethylzinc (DMZn) precursors and the variation of the group VI/group II gas phase ratio on the electrical and optical properties of epitaxial ZnSe grown by atmospheric pressure MOCVD on (100) GaAs substrates have been investigated. Three purified DMZn sources were used which contained known concentrations of iodine, together with hydrogen selenide as a source of selenium. The highest carrier concentrations were recorded in ZnSe grown using the DMZn source containing the highest iodine concentration (0.9 ppm). In all cases the carrier concentration showed a decrease with the increase of the VI/II ratio. Strong features due to donor bound exciton transitions are observed in the photoluminescence spectra recorded at 10 K of samples grown at a low VI/II ratio, whereas at high VI/II ratios the spectrum decreases in overall intensity. In the case of the ZnSe grown from the DMZn containing a high iodine concentration, the I2 emission is replaced by the Ix emission attributable to the same impurity species in a state of different polarization. At high VI/II ratios, emissions such as Iv and Ex due to intrinsic features in the epilayer are more intense. The impurity responsible for the change in carrier concentration with VI/II ratio is considered to be mainly iodine in very low concentration occupying vacant selenium sites, VSe. The VSe concentration is lower at high VI/II ratios. ZnSe grown from the DMZn source containing the least iodine (0.2 ppm) gave photoluminescence spectra with the near band edge linewidths as narrow as 1.9 meV and carrier concentrations down to 1014 cm−3.

Effects of iodine concentration on iodine-induced stress corrosion cracking of zircaloy-4 tube

Iodine-induced stress corrosion cracking (I-SCC) experiments on Zircaloy-4 tube were undertaken in the iodine concentration range of 0–4 mg/cm 2, the temperature range of 330–400 ° C and a nominal hoop stress of 475 MPa, using the internal pressurization method. The time-to-failure, failure strain and strain rate were measured as a function of the iodine concentration. An apparent activation energy for I-SCC was calculated from the temperature dependence of I-SCC. A fractographic interpretation was also made through scanning electron microscopic examination. The results suggest that the iodine concentration has an influence on the crack propagation step to increase the propagation rate of I-SCC, promoting the I-SCC susceptibility. It is found that the critical iodine concentration means the phenomenological value to show the iodine concentration dependence of I-SCC susceptibility, not the critical value to determine the occurrence of I-SCC. The I-SCC behavior of Zircaloy is discussed from the viewpoint of the crack initiation and propagation process.

Iodine stress corrosion cracking of zircaloy: Laboratory data, a phenomenological model, and predictions of in-reactor behavior

Data from laboratory tests performed on unirradiated and irradiated Zircaloy have been used as the basis for developing a phenomenological model of iodine-induced stress corrosion crack initiation and growth. The model is capable of predicting the response of cladding subjected to complex loading conditions. Major features of the data incorporated into the model include the existence of a threshold stress, the effect of iodine concentration, temperature effects, the role of chemical inhomogeneities and mechanical flaws, crack initiation in smooth specimens, crack propagation rates as a function of stress intensity in flawed specimens, and the detrimental effect of irradiation. The major physical processes addressed by the model include intergranular stress corrosion cracking (SCC), transgranular SCC, ductile rupture, iodine penetration by surface diffusion along existing or incipient cracks, and stress and strain intensification and triaxiality caused by cracks or flaws. A probabilistic description of the size distribution of the flaws found in as-fabricated cladding is used as the basis for quantitatively extrapolating the laboratory test results to predict in-reactor cladding behavior. The in-reactor SCC resistance of a large fuel assembly is predicted to be substantially lower and more variable than that of small laboratory specimens.