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Pristine magnesium spinel ferrite nanoparticles (MgFe2O4, MNPs) were fabricated via sol–gel auto combustion and elucidated by XRD, SEM, EDAX, TEM, FTIR, BET and VSM for structural and physical characteristics. Fabricated MgFe2O4 MNPs found to be an efficient, robust and magnetically separable reusable heterogeneous catalyst for one pot three component solvent free synthesis of biologically important 1,4-dihydropyridines (1, 4 DHP's) via Hantzsch condensation reaction. This convention was effectively appropriate to an extensive variety physically distinct aryl-aldehydes with ethyl acetoacetate and ammonium acetate to manage the required 1,4-dihydropyridines (1, 4 DHP's) derivatives. The structural investigations approved the sustainability and reusability of the MgFe2O4, MNPs towards current organic reactions. The novelties of this protocol are operational cleanness, short reaction time, nontoxic, inexpensive and magnetically separable heterogeneous catalyst may perhaps easily be recycled deprived of remarkable decline in catalytic performance. [ABSTRACT FROM AUTHOR]

In this work, we have proposed a cascade of notch filters with linear transformation (LT) methods to enhance MRI brain images. The proposed method is compared with the inner and inter-class of spatial, frequency and other methods. The performance is evaluated by using quantitative measures like Michelon contrast (MC), entropy, peak signal to noise ratio (PSNR), structure similarity index measurement (SSIM), and absolute mean brightness error (AMBE) as a parameter on BRATS-2019 dataset. The proposed method gives good results for entropy, PSNR, MC, RMSE and SSIM. [ABSTRACT FROM AUTHOR]

This paper presents a blueprint for major exploration advances in graphene-based nanolubricants and nanofluids achieved over the last few years. Graphene is being studied worldwide as a coolant and lubricant additive due to its excellent thermophysical and tribological properties. With this in mind, a variety of synthesis methods, characterization techniques, and methods are highlighted for studying tested and developed properties. In addition to that, factors influencing the thermal conductivity, viscosity, stability, and applications of different nanoparticles are described in detail. Improvement of viscosity, antiwear, and thermal conductivity behavior of graphene-based nanofluids plays a vital role, but not many mechanisms have been introduced. Graphene nanoparticles are most effective and promising the better heat transfer rate among other mostly used nanoparticles in the cooling and lubricant sector. It increases the effectiveness almost two times at higher concentration suspended in water. This complete overview, along with key comments and recommendations, may relate to future headings in this audit area. [ABSTRACT FROM AUTHOR]

The article titled "A review on emotion recognition from dialect speech using feature optimization and classification techniques" has been retracted by the Editor-in-Chief and the publisher due to concerns identified during an investigation. These concerns include citations that do not support the claims made in the text, non-standard phrasing, and image irregularities. The Editor-in-Chief no longer has confidence in the results and conclusions of the article. The authors have expressed disagreement with the retraction. The online version of the article includes the retracted article as Supplementary Information. [Extracted from the article]

In this paper, the correlation of the citation count and Mendeley readership score of the articles by the Sri Lankan authors was studied. The study presents how the correlation exists among different Web of Science (WoS) subject categories and in different Mendeley user categories. Nine thousand one hundred thirty articles of Sri Lankan authors are collected from the WoS database, with a minimum of 5 citation counts, and analyzed to trace their correlation with Mendeley readership from different aspects. Quantitative methods were applied in the study. A strong correlation exists between the citation count and Mendeley readership. 'Chemistry', 'Public, Environmental & Occupational Health' and 'Engineering' were observed as the highly indexed subjects in the category-wise analysis, though it does not affect the readership and citation. Subjects with a higher Mendeley readership score strongly correlate with a citation in different user categories, and articles with less than 200 readership scores mostly tend to show a negative correlation. Mendeley is more prevalent among researchers, Ph.D. students and master's students than in other user categories, and in all the user categories, correlation is more or less favourable. [ABSTRACT FROM AUTHOR]

Development and demonstration of soluble lead redox flow battery (SLRFB) is hindered due to its limited cycle life caused by the formation of lead dendrites, oxygen evolution reaction (OER), and accumulation of PbO2 sludge. OER leads to an imbalanced deposition of Pb metal at anode and PbO2 at cathode. As a result, complete oxidation of Pb is stalled during discharge of SLRFB. Besides, sluggish kinetics of cathode reaction results in accumulation of PbO2. Due to incomplete dissolution and accumulation of both active materials, concentration of Pb2+ decreases continuously in the electrolyte. Under such conditions, repeated charge–discharge cycling leads to the failure of SLRFB. In this study, we propose and demonstrate a novel route of using an auxiliary gas-diffusion electrode to obviate these problems to help in extending the cycle life of SLRFB. The auxiliary electrode is operated either as an air electrode or a hydrogen electrode. When the auxiliary electrode is an air electrode, it is used as positive electrode, and on coupling with anode of SLRFB, it forms a galvanic Pb–air flow cell that on discharge helps in oxidizing Pb metal to Pb2+ ions. When the auxiliary electrode is a hydrogen electrode, it is used as negative electrode, and on coupling with cathode of SLRFB, it forms a galvanic H2–PbO2 flow cell which on discharge reduces PbO2 to Pb2+ ions and mitigates the adverse effect of sludge accumulation in SLRFB. [ABSTRACT FROM AUTHOR]

The effect of varying wick structures viz. mesh, sintered and composite wick (sintered-mesh) on the thermal enhancement of cylindrical heat pipes is experimentally investigated. In addition, the investigation focused on the effect of inclination angle and heat input of heat pipe. Surfactant free CuO nano-fluid with a mass concentration of 1.0% is used as a working fluid. The energy and exergy analysis of heat pipe was also conducted at various conditions. To analyze the distinctive performance of composite heat pipe, a heat pipe is filled with DI water and the obtained results are compared with nanofluid results. The maximum heat transfer capability of composite heat pipe is improved by 35.71% and 18.75% compared with mesh and sintered wicks. The composite heat pipe with CuO nanofluid as working fluid instead of DI water improves the heat transport capacity by 11.76%. Surface temperature of heat pipe significantly reduces by varying the wick structure viz. mesh, sintered and composite wick. The composite heat pipe with 1.0 mass% of CuO nanofluid obtained 3.7 °C reduction in surface temperature at evaporator section compared with DI water. Thermal resistance of heat pipe is gradually reduces with increasing inclination angle. The maximum reduction is observed for composite wick, sintered and mesh wick heat pipes are 47.50, 43.70 and 24.39% respectively at 45° inclination angle compared with horizontal axis. [ABSTRACT FROM AUTHOR]

In this investigation, an attempt has been made to hardness and wear rate of Al7075 hybrid metal matrix composite reinforced with the hard ceramics like alumina (2, 4, and 6 wt.% of Al2O3) and silicon carbide (3, 6, and 9 wt.% of SiC) is fabricated by using stir casting method. The samples were aging at temperature of 140 ∘C, 160 ∘C and 180 ∘C and monitored by hardness test. Taguchi’s L27 Orthogonal array was used for optimizing the process parameters. The obtained results indicated that hardness increased with increasing reinforcement. A wear test was performed using pin-on disk apparatus at room temperature for constant load of 30N, at a fixed sliding speed of 1.66 m/s and wear resistance increased as the weight percentage of reinforcement increased. Scanning electron microscope (SEM) studies were carried out to evaluate the worn surface. From the analysis of variance (ANOVA), Al2O3 is the significant factor that affects the hardness and wear loss of hybrid composites followed by SiCp and heat treatment. Confirmatory test was performed for the optimized parameters and these results were within the acceptable range when compared with the experimental results. [ABSTRACT FROM AUTHOR]

Gadolinium-doped cadmium oxide (CdO) thin films were fabricated by spray pyrolysis technique using a perfume atomizer on the glass and silicon substrates at 350 °C. The effect of increasing Gd concentration on the electrical, morphological, optical, and structural properties of deposited films was analyzed. Structural analysis of the pristine and doped CdO thin films showed cubic structures with preferred orientation of (200) direction. The estimated crystallite values ranged from 15 to 21 nm. The structural parameters like dislocation density, microstrain, a number of crystallites per unit area, and texture coefficient were also studied. Scanning electron microscope (SEM) images showed uniformly oriented and cauliflower-like nanostructures grown on the glass substrate for 3at.%-doped CdO films. The doped films' optical transmittance is found to be initially increased and systematically decreased with respect to doping concentrations. The band gap value is in the range of 2.42-2.30 eV for various Gd-doping concentrations (0, 1, 3, and 5%), respectively. The photoluminescence spectra (PL) of films were studied at room temperature and confirms the visible and green emission' peaks are at wavelength 463 and 528 nm, respectively. From the Hall Effect studies, it proved that all the CdO films belong to an n-type degenerate semiconductor, and the low electrical resistivity value was around 3.64 × 10 Ω cm. The n-CdO/p-Si structure with different doping concentrations was subjected to photoconductivity studies and found that it is the maximum of 3% Gd concentration. Higher values of photo responsivity and quantum efficiency was found ~365 mA/W and ~76.64%, respectively, for 3at.% Gd-doped CdO films. Graphical abstract: [ABSTRACT FROM AUTHOR]

Although redox flow batteries were invented as early as 1954, no system development took place until NASA demonstrated an Fe/Cr redox flow battery system in 1970s. In hibernation for several years, redox flow battery systems have begun to catch the attention of policy makers globally. The resurrection of redox flow batteries rests heavily on their techno-economic feasibility as large-scale energy storage systems for emerging grid network that are being developed by climate change mitigation industries, namely, wind and solar. This article reviews various redox flow battery technologies with a cost and market prognosis. [ABSTRACT FROM AUTHOR]

The original version of this article unfortunately published with incorrect version of Figs 2, 3 and 4. The corrected figures are given below. [ABSTRACT FROM AUTHOR]

Short-chain fatty acids (SCFAs) acetate, propionate, butyrate and lactate were determined in 12 % reconstituted skim milk (RSM) and RSM supplemented with inulin (RSMI). The fermentation was performed with Bifidobacterium animalis subsp. lactis (BB 12) and Lactobacillus rhamnosus LGG ATCC 53013. Fermentation culture activities produced substantial amounts of SCFAs, which were detected and quantitated using a HPLC-UV technique. Using HPLC-UV, we were able to detect low concentrations of lactate and SCFAs from fermented samples; lactate, acetate, propionate and butyrate were detected at 10.10, 12.06, 14.80 and 18.06 μg/mL, respectively. The retention time of all SCFAs and lactic acid were similar to the standard quality control (±0.05), and average recovery ranged between 89.73 and 91.03 %. The experimental conditions and sample preparation were applied to preparative HPLC to isolate and purify SCFAs with concentration range between 0.09 and 2.86 mg/mL. The purity of extracted SCFAs was confirmed using atmospheric pressure chemical ionization/mass spectrometry by determining the molecular masses of target purified compounds. The scaled up validated analytical HPLC-UV method will further enhance and improve the use of this approach to produce purified large-scale SCFAs. [ABSTRACT FROM AUTHOR]

CdO thin films were deposited on glass and silicon substrates by simple perfume atomizer at 350°C using cadmium acetate and trisodium citrate (TSC). The effect of the TSC concentration on the structural, morphological, optical, and photoconductive properties of the prepared CdO thin films was investigated. X-Ray diffraction (XRD) studies of the deposited films revealed improvement in crystalline nature with increase of TSC concentration. Films prepared without TSC showed porous nature, not fully covering the substrate, whereas films prepared using TSC exhibited full coverage of the substrate with uniform particles. Optical transmittance study of the films showed high transmittance (50% to 60%), and the absorption edge was found to shift towards the red region depending on the TSC concentration. The films exhibited a direct band-to-band transition with bandgap varying between 2.31 eV and 2.12 eV. Photoconductivity studies of the n-CdO/ p-Si structure for various TSC concentrations were also carried out. I- V characteristics of this n-CdO/ p-Si structure revealed the formation of rectifying junctions, and its photoconductivity was found to increase with the TSC concentration. [ABSTRACT FROM AUTHOR]

We analyzed of heat transmission across three roof structures ; bare RCC (reinforced cement concrete) roof, RCC roof with weathering coarse and RCC roof with PCM (phase change material) above RCC. A transient numerical procedure was developed. ANSYS-Fluent 12 finite volume method based software was used for solving the problem. The numerical procedure was validated against the available experimental data. The simulation was carried out on 365 days of the year for these three roofs. The PCM melted from 8 h to 18 h and solidified during the rest of the day. From March to August, the net heat entering into the room per day is positive, thus more and more PCM melts and becomes liquid. The liquid portion of PCM increases from March to August, during September to February, there is a net heat rejection per day, thus the melted PCM becomes solid progressively, and at the end of February, almost all PCM has become solid. Thus there is a melting cycle on a daily basis and over the year. It takes care of all the external climatic variations and keeps the roof bottom surface temperature almost constant and close to room air temperature. On yearly basis, about 56% reduction in heat transmission into the room is obtained with PCM roof when compared to the conventional weathering coarse laid roof. [ABSTRACT FROM AUTHOR]

Lead-Carbon hybrid ultracapacitors (Pb-C HUCs) with flooded, absorbent-glass-mat (AGM) and silica-gel sulphuric acid electrolyte configurations are developed and performance tested. Pb-C HUCs comprise substrate-integrated PbO (SI-PbO) as positive electrodes and high surface-area carbon with graphite-sheet substrate as negative electrodes. The electrode and silica-gel electrolyte materials are characterized by XRD, XPS, SEM, TEM, Rheometry, BET surface area, and FTIR spectroscopy in conjunction with electrochemistry. Electrochemical performance of SI-PbO and carbon electrodes is studied using cyclic voltammetry with constant-current charge and discharge techniques by assembling symmetric electrical-double-layer capacitors and hybrid Pb-C HUCs with a dynamic Pb(porous)/PbSO reference electrode. The specific capacitance values for 2 V Pb-C HUCs are found to be 166 F/g, 102 F/g and 152 F/g with a faradaic efficiency of 98%, 92% and 88% for flooded, AGM and gel configurations, respectively. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A gradient reversed-phase liquid chromatographic assay was developed for the quantitative determination of the non-steroidal anti-inflammatory drug valdecoxib. The developed method was also applicable to the determination of related substances in the bulk drug. Forced degradation studies were performed on bulk valdecoxib using acid (2.0 N hydrochloric acid), base (2.0 N sodium hydroxide), oxidation (6.0% v/v hydrogen peroxide), water hydrolysis, heat (60 °C) and photolysis. Mild degradation was observed using alkaline conditions and considerable degradation observed during oxidative stress. Chromatographic separation of process-related impurities and degradation products was achieved using a 5 micron Zorbax SB-CN LC column. The mobile phase consisted of aqueous potassium dihydrogen phosphate (pH 3.0) and acetonitrile. Stressed samples were assayed using the developed LC method and determination of the mass balance accounted for 99.5%, thus indicating the suitability of this stability-indicating method. Linearity, accuracy, precision and robustness have also been evaluated. [ABSTRACT FROM AUTHOR]

The present work narrates an LC method for determination of enantiomeric purity of (4 S,5 R)-3,5-oxazolidinedicarboxylic acid 2,2-dimethyl-4-phenyl-3-(1,1-dimethylethyl) ester, which is a key starting material of docetaxel, an antineoplastic agent and belongs to the taxoid family. Resolution between enantiomers was achieved ≥4.0 within 30 min on Chiralpak AD-H (250 mm × 4.6 mm) column using n-hexane, 2-propanol, ethanol and trifluoroacetic acid (97.5, 1.5, 1.0, 0.15 v/v) as mobile phase at a flow rate of 1.0 mL min−1 at 25 °C. The detection was made at 215 nm using UV detection. The effects of 2-propanol, ethanol and temperature on enantioselectivity and resolution of enantiomers were evaluated. The method was validated for (4 R,5 S)-enantiomeric impurity in terms of accuracy, precision and linearity in the range of 0.5–5 μg mL−1 and the correlation coefficient was >0.999. The recoveries were 93.2–104.4%. The limits of detection (LOD) and quantification (LOQ) of unwanted (4 R,5 S)-enantiomer was 0.1 and 0.5 μg mL−1. The method was found to be suitable for rapid quantification of (4 R,5 S)-enantiomer of docetaxel starting material. [ABSTRACT FROM AUTHOR]

A new stereospecific LC method for the separation and quantification of moxifloxacin and its ( R, R)-enantiomer in bulk drug was developed and validated by ligand-exchange liquid chromatography on a reversed phase column using aqueous mobile phase containing the chiral reagent l-isoleucine-Cu(II). The UV detector was operated at 293 nm. The flow rate of mobile phase was set at 0.9 mL min−1. The achiral ODS column offers good separation of the two enantiomers in less than 20 min. The test concentration was 1,000 μg mL−1 in the mobile phase. This method was capable of detecting the ( R, R)-enantiomer of moxifloxacin up to 0.1 μg mL−1 for a 20 μL injection volume. The drug was subjected to stress conditions of hydrolysis, oxidation, photolysis and thermal degradation. There was no interference of degradants with the ( R,R)-enantiomer in the developed method. The developed chiral RP-LC method was validated with respect to linearity, accuracy, precision and robustness. The percentage recovery for the ( R, R)-enantiomer in bulk drug samples ranged from 98.1 to 104.4%. The test solution was found to be stable in the mobile phase for 48 h after preparation. [ABSTRACT FROM AUTHOR]

A simple, inexpensive and rapid isocratic LC method has been developed for the quantative determination of Rimonabant, an anti-obesity drug. The method can also be employed for the determination of Rimonabant and its impurities in the bulk drug. Degradation studies were performed on the bulk drug by heating to 60 °C, exposure to UV light at 254 nm, acid (0.5 N hydrochloric acid), base (0.5 N sodium hydroxide) and aqueous hydrolysis and oxidation with 3.0% v/v hydrogen peroxide. Considerable degradation was observed under oxidation conditions. Good resolution between the peaks corresponding to impurities produced during synthesis, degradation products and the analyte was achieved on a Phenomenex Gemini C18 LC column using a mobile phase consisting of a mixture of aqueous potassium dihydrogen phosphate (pH 3.0) and acetonitrile. The degradation samples were assayed against the reference standard of Rimonabant and the mass balance in each case was close to 99.5%. Validation of the method was carried out as per ICH requirements. [ABSTRACT FROM AUTHOR]

This present work describes the development of a stability-indicating high performance liquid chromatographic method for the quantitative determination of pemetrexed disodium. Pemetrexed disodium is an antifolate antineoplastic agent that exerts its action by disrupting folate-dependent metabolic processes essential for cell replication. The chromatographic separation was achieved on an ACE 3 C18 HPLC column using a mobile phase consisting of a mixture of buffer (solvent A) and organic modifier acetonitrile (solvent B). Forced degradation studies were performed on bulk sample of pemetrexed disodium using acid (0.5 N hydrochloric acid), base (0.5 N sodium hydroxide), oxidation (10% v/v hydrogen peroxide), heat (60 °C) and UV light (254 nm). Degradation of the drug substance was observed in base hydrolysis. Degradation product formed under acid and base hydrolysis was found to be starting material. The stressed samples were assayed using the developed LC method and the mass balance found was close to 99.5%, thus proving its stability-indicating power. The developed method was validated with respect to linearity, accuracy, precision and robustness. [ABSTRACT FROM AUTHOR]

This present work narrates the stress stability behavior and development of a liquid chromatographic method for the quantitative determination of anastrozole. Anastrozole is appropriately used when using substantial amounts of aromatizing steroids, or when one is prone to gynecomastia and using moderate amounts of such steroids. A chromatographic separation was achieved on a Hichrom RPB18 (250 × 4.6 mm, 5 μ) column using water and mixture of acetonitrile and methanol (1:1 ratio) as mobile phase. Forced degradation studies were performed on bulk samples of anastrozole using acid, base, hydrogen peroxide, heat and UV light. Degradation of the drug substance was observed in base hydrolysis. Degradation product formed under base hydrolysis was found to be Imp-C. The sample solution and mobile phase were found to be stable up to 48 h. The developed method was validated with respect to linearity, accuracy, precision, robustness and forced degradation studies prove the stability indicating power of the method. [ABSTRACT FROM AUTHOR]

A stability-indicating HPLC method for the quantitative determination of Bicalutamide is described. Bicalutamide is a nonsteroidal antiandrogen and is an oral medication that is used for treating prostate cancer. Separation was achieved on a Waters Symmetry shield RP18 HPLC column using a mobile phase consists of a mixture of phosphate buffer (Solvent A) and organic modifier acetonitrile (Solvent B). Degradation studies were performed on bulk samples of bicalutamide using acid (0.5 N methanolic hydrochloric acid), base (0.5 N methanolic sodium hydroxide), oxidation (10% v/v methanolic hydrogen peroxide), heat (60 °C) and UV light (254 nm). Degradation was observed under base hydrolysis to give the starting material used during the synthesis of bicalutamide. The degraded samples were assayed and gave a mass balance greater than 99.5%, thus proving the stability-indicating power of the developed method. The method was validated with respect to linearity, accuracy, precision and robustness. [ABSTRACT FROM AUTHOR]

Chromatographic separation of lenalidomide and its impurities was achieved on an Inertsil ODS-3 V column using a mobile phase consisting of a mixture of buffer, acetonitrile and methanol in the ratio 80:8:12 v/v. Degradation studies were performed on bulk samples of lenalidomide subjected to 0.5 N hydrochloric acid, 0.5 N sodium hydroxide, 10% v/v hydrogen peroxide, heating to 60 °C and UV light at 254 nm. Degradation was observed only under base hydrolysis conditions. The developed LC method gave a mass balance close to 99.5%, proving it to be suitable for stability studies and was validated with respect to linearity, accuracy, precision and robustness. [ABSTRACT FROM AUTHOR]

This study deals with a stability indicating HPLC reverse phase method for quantitative determination of temozolomide. A chromatographic separation was achieved on an Inertsil ODS 3V, 250 × 4.6 mm ID, 5 μm column using mobile phase A (buffer 5 mL glacial acetic acid in 1,000 mL of Milli Q water ) and mobile phase B (methanol). Forced degradation studies were performed on bulk sample of temozolomide using acid (0.5 N hydrochloric acid), base (0.5 N sodium hydroxide), oxidation (10% v/v hydrogen peroxide), heat (60 °C) and UV light (254 nm). Degradation of the drug substance was observed in base hydrolysis and oxidation. Degradation product formed under these conditions was found to be Imp-A. When the stress samples were assayed, the mass balance was close to 99.5%. The sample solution was stable up to 48 h at 5 °C and mobile phase was found to be stable up to 48 h at 25 °C. The developed method was validated with respect to linearity, accuracy, precision, robustness and forced degradation studies prove the stability indicating power of the method. [ABSTRACT FROM AUTHOR]

The efficacy of supravital staining in the detection of malignancies in oro and oropharyngeal lesions and its role in the detection of malignant changes in premalignant lesions were studied. This prospective study comprises 90 cases of clinically suspicious lesions and it was done over a period of 3 years. Most of the patients had multiple risk factors for the development of malignancy. All underwent staining with a modified solution of 1% toluidine blue (TB). In our study the overall sensitivity was 97.29% and the specificity was 62.5%. [ABSTRACT FROM AUTHOR]

A 12-year-old girl, with incessant atypical idiopathic left ventricular tachycardia, underwent successful radiofrequency ablation of ventricular tachycardia focus originating from a subepicardial site adjacent to the left coronary cusp. Ventricular tachycardia was successfully eliminated by targeting an endocardial site concordant to the epicardial site of early activation. Epicardial mapping was useful in locating an effective ablation site, and aortic root angiography was used to avoid potential injury to important structures, such as the left main coro-nary artery and left coronary cusp. [ABSTRACT FROM AUTHOR]

Copyright of Strahlentherapie und Onkologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Strahlentherapie und Onkologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Strahlentherapie und Onkologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dramatic technological advances for the proton exchange membrane fuel cell have focused attention on this technology for motor vehicles. The fuel cell vehicles (FCVs) have the potential to compete with the petroleum-fueled internal combustion engine vehicles (ICEVs) in cost and performance while effectively addressing air quality, energy insecurity, and global warming concerns. Methanol being a liquid can be easily transported and can be supplied from the existing network of oil company distribution sites. Recently, combining improved catalysts with fuel cell engineering, it has been possible to overcome some of the difficulties that have frustrated previous research and development efforts in realizing a commercially viable direct methanol fuel cell. Direct methanol fuel cells (DMFCs) with power densities between 0.2 and 0.4 W/cm2 at operational temperatures in the range 95–130 °C have been developed. These power densities are sufficient to suggest that stack construction is well worth while. This paper reviews recent advances and technical challenges in the field of DMFCs. [ABSTRACT FROM AUTHOR]

The K-electron capture probabilities in the decay ofAu characterising 2→2 non-unique first forbidden transitions to the levels 688.7 and 355.7 keV in the daughterPt were measured for the first time using the X-γ summing method. The respective P values are found to be 0.776±0.038 and 0.847±0.051 in agreement with the theory. The K-electron capture probability for the non-unique first forbidden transition 1/2→1/2 in the decay ofHg to the 77.35 keV level in the daughterAu was measured to be 0.778±0.014 in agreement with the theory. [ABSTRACT FROM AUTHOR]

A perfume atomizer-assisted spray pyrolysis method was employed to fabricate undoped and neodymium (Nd)-doped cadmium oxide (CdO) thin films. X-ray diffraction results reveal that all the films are polycrystalline with a cubic structure with a preferential orientation along the (200) direction. Scherrer's formula was used to calculate the crystallite size of Nd-doped CdO films. Energy dispersive spectroscopy results show that Cd, Nd and O elements are present in Nd-doped CdO thin films. The optical absorption of the doped films is increased along with increasing Nd-doping level. The prepared CdO thin films have a high absorption coefficient in the visible region and the optical band gap is decreased on increasing Nd doping content. The electrical carrier concentration (n) of the deposited films is increased with increasing Nd doping concentration. Photoconductivity studies of a nanostructured Al/Nd-n-CdO/p-Si/Al device showed a non-linear electric characteristics indicating diode-like behaviour. Prepared Nd:CdO films could increase the photo-sensing effect of this n-CdO/p-Si heterostructure. These Nd-doped CdO thin films may open a new avenue for photodiode application in near future. [ABSTRACT FROM AUTHOR]