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The major drawback of zirconia-based materials, in view of their applications as targets for minor actinide transmutation, is their poor thermal conductivity. The addition of MgO, which has high thermal conductivity, to zirconia-based materials is expected to improve their thermal conductivity. On these grounds, the present study aims at phase characterization and thermophysical property evaluation of neodymium-substituted zirconia (Zr0.8Nd0.2O1.9; using Nd2O3 as a surrogate for Am2O3) and its composites with MgO. The composite was prepared by a solid-state reaction of Zr0.8Nd0.2O1.9 (synthesized by gel combustion) and commercial MgO powders at 1773 K. Phase characterization was carried out by X-ray diffraction and the microstructural investigation was performed using a scanning electron microscope equipped with energy dispersive spectroscopy. The linear thermal expansion coefficient of Zr0.8Nd0.2O1.9 increases upon composite formation with MgO, which is attributed to a higher thermal expansivity of MgO. Similarly, specific heat also increases with the addition of MgO to Zr0.8Nd0.2O1.9. Thermal conductivity was calculated from measured thermal diffusivity, temperature-dependent density and specific heat values. Thermal conductivity of Zr0.8Nd0.2O1.9–MgO (50 wt%) composite is more than that of typical UO2 fuel, supporting the potential of Zr0.8Nd0.2O1.9–MgO composites as target materials for minor actinides transmutation.

Platelet indices have been used to diagnose and prognosticate infections such as tuberculosis, malaria, dengue, and septic shock. Platelet indices have previously not been used in the prediction of multiorgan dysfunction (MODS) in patients with scrub typhus. A three-year retrospective review of patient charts was performed. Patients with and without MODS were compared. Platelet indices and other clinical and laboratory variables were used in logistic regression analysis to determine significant predictors. A ROC curve was generated with the platelet indices to predict MODS. Of 189 patients, 106 were male. Respiratory rate, serum creatinine, liver function tests, platelet count, thrombocytopenia 7.3 fL, and plateletcrit ≤0.19% varied significantly between patients with MODS and those without. Platelet indices are inexpensive and easily available. Only thrombocytopenia along with creatinine, alanine transaminase, and abnormal chest radiograph could significantly predict MODS in patients with scrub typhus.

Beans are one of the world's most consumed and widely grown vegetable crops, but their yield is hampered by a variety of diseases caused by whiteflies and other insects.Whiteflies can also spread a variety of viral diseases to beans. Bean Common Mosaic Virus (BCMV), Bean Yellow Mosaic Virus (BYMV), Bean Golden Mosaic Virus (BGMV) etc. A variety of synthetic pesticides have been used in agriculture to control insects, which damage the plant and have a negative impact on the environment; however, their negative impact on the environment necessitates the use of more environmentally friendly methods for pest management. This paper discusses the synthesis, physicochemical characterization, and application of a mixture of potassium palmitate and pyrethroids; pyrethroids, and potassium stearate as non- persistent insecticides against whiteflies found on bean plants, as well as the use of the T-test to compare the efficacy of prepared insecticidal formulations.

BACKGROUND Diabetes is a global epidemic with devastating human, social and economic consequences associated with various short and long-term complications, many of which, have the potential to reduce the quality of life of people with diabetes and their families. Diabetic foot associated complications are one of the most serious complications of diabetes causing morbidity. Proper diabetic foot care organisation, proper diabetes control and well-educated self-care methods to diabetics can cause significant reductions in amputations. We wanted to evaluate the knowledge with regard to foot care practises and foot self-care among diabetic patients there by identifying and addressing barriers to preventing amputations among diabetic patients. METHODS Our study was a prospective cross-sectional study conducted in the department of General Medicine, Indira Gandhi Medical College and Research Institute, Pondicherry. Two hundred patients with type 1/ type 2 diabetes mellitus were included. The respondents were further divided into two groups based on diabetic foot ulcer questionnaire derived from American College of Physicians, into those with a past history of foot ulcer and those without ulcer. Data was analysed by using IBM SPSS version 22 for Windows. RESULTS Of the 200 patients assessed, 126 were men. Twenty-two (11%) of the 200 had a current or past history of foot ulcers. Out of a possible score of 26, the average score on overall foot care was 16.29 (range of 9-23). Twenty-two (22/200) had a past history of ulcer. Similarly, two-thirds of both groups of patients (with and without ulcer) had fair scores. Educational status of patients did not have any significant correlation with knowledge & practices regarding foot care. CONCLUSIONS The prevalence of diabetic foot is high among patients attending diabetic clinics in our setup and there is an urgent need to emphasise coordinated foot care services within the diabetic clinic to identify feet at risk, start early management, and provide continuous foot care education to patients and health care providers.

Nature of interaction between Th4+, glycine, and nitrate ions and associated thermo chemical-changes prior to glycine-nitrate gel combustion for the synthesis of ThO2 powder have been investigated by DSC and XRD techniques, combined with FT-IR and Raman spectroscopic measurements. Combustion of dried gel is preceded by a distinct exothermic process; origin of which has been probed by systematic analysis of DSC thermograms. Mono- and multi-nuclear complexes of thorium with glycine exist in the gel before combustion and their relative concentrations depend on the starting stoichiometry, heat treatment temperature and extent of water content. Depending on the rate at which water gets removed from the gel, complexes mentioned above undergo rapid or slow aggregation to form amorphous or crystalline molecular solids. Observed additional exothermic peak in DSC thermogram prior to combustion of the gel confirms the formation of such molecular solids.

Arc melting technique, which is widely used for preparation of alloys, intermetallics, and metal-based composites, is discussed in this chapter. Basic principle of electrical arc generation and its utilization for melting of materials has been outlined. Design and operation of laboratory-scale arc melting furnace as well as melt-casting furnace have been presented. Operational principle of graphite arc furnace and consumable electrode-based industrial arc furnace is also mentioned. Advantages and limitations of arc melting technique are summarized with few examples towards the conclusion. Contents of this chapter would be useful to students and researchers engaged in development of metallic materials.

Background The severity of acute alcohol-related pancreatitis (AAP) with alcohol withdrawal syndrome (AWS) has not been studied. Electrocardiogram (ECG) has not been used as a predictor of severity in patients with AWS and acute pancreatitis. Objectives The study aimed to determine whether the ECG heart rate (HR) could predict the severity of AAP; secondarily, whether AWS influenced the severity of AAP based on Acute Physiology and Chronic Health Evaluation (APACHE) II and Bedside Index for Severity in Acute Pancreatitis (BISAP). Methods Demographics, comorbid illnesses, AWS, biochemistry, ECG, arterial blood gases, and CT findings were noted in patients with AAP. The severity of pancreatitis was scored into mild, moderate, and severe based on CT. BISAP, APACHE II, and ECG heart rate-APACHE (E-APACHE) were compared in patients with and without AWS. A receiver operating characteristic curve was used to find the best predictor of severity. Results Among 138 patients (M=128), 94 had AWS. ECG changes (≥1) were seen in 50%. Patients with AWS were younger, had consumed alcohol for a shorter duration, had higher systemic inflammatory response syndrome (SIRS), APACHE II, and E-APACHE II scores. APACHE II and E-APACHE II correlated significantly with severity grading, HR, alcohol duration, and AWS. HR was the best predictor of severe pancreatitis; E-APACHE was the best predictor for moderately severe pancreatitis. Conclusions Mostly, AAP appears to be mild; >2/3rds have AWS. ECG findings were seen in 50%. HR has not been previously studied in patients with both AAP and AWS and is an easy and inexpensive test to predict the severity of pancreatitis in this cohort.

This is the first study undertaken towards development of mixed-matrix membranes (MMMs) with enhanced radiation resistant attributes by reinforcement of nanostructured Gd2Zr2O7 (GZO) within polysulfone (Psf) host-matrix. The study describes synthesis and characterization of GZO in disordered, defect-fluorite structure, having average crystallite size of 31(±3) nm. Membranes prepared with different loading of GZO (up to 2 w/w% of Psf) are exposed to γ-radiation up to a dose of 1000 kGy in aqueous environment. The effect of radiation on the structural, mechanical, and thermo-oxidative properties of MMMs has been compared with that of radiation-sensitive Psf membrane. The ultrafiltration performance of the (un)irradiated Psf and MMMs reveal that an optimum reinforcement of GZO at 1 (w/wPsf)% offers ~10 times radiation resistant MMM, compared to that of Psf membrane. The MMM with 1 (w/wPsf)% GZO was rolled into 2512 spiral configuration and a highly-compact device was developed for treatment of radioactive effluent. Based on the flux decline behaviour over 18 months duration, the fouling behaviour of the MMM module was modelled. The life-span of the MMM was predicted based on the absorbed radiation dose, GZO leaching study, and fouling behaviour. It is proposed that GZO mitigates a fraction of the impinged γ-energy in swapping of the Gd3+ and Zr4+ sites, which protects the polymeric host-matrix in-situ from radiation induced degradation. The abundance of Gd3+ and Zr4+ associated with polar O2− over the impregnated GZO further stabilizes MMMs through scavenging of the oxidizing and reducing radiolysed products of water. Thus, we report a smart approach to develop novel MMM with greater life-expectancy against high-energy radiation and further fabricate a membrane-based device for management of liquid radioactive waste.

Background: The commonly available platelet indices are platelet distribution width (PDW), plateletcrit (PCT), and mean platelet volume (MPV). They have been used in diagnosis and prognosis of various abdominal disorders. They have never been used to predict severity of alcoholic hepatitis. Methods: A retrospective analysis of chronic alcohol consumers presenting with jaundice and deranged liver function tests was performed. Maddrey discriminant function (MDF) and modified end-stage liver disease (MELD) scores were calculated and patients compared between severe and nonsevere alcoholic hepatitis (MDF ≥32 vs MDF 20 vs MELD ≤20). Logistic regression analysis was performed to find significant predictors. Receiver operating characteristic was used to find the area under the curve. Spearman correlation was performed to discover association between platelet indices and severity scores. Results: There were 119 patients in the study. Coexisting illnesses included pancreatitis, cirrhosis, infections, and alcohol withdrawal syndrome. The mean age (years), duration of alcohol consumption (years), and ethanol (g/day) were 45.13 ± 11.53, 18.84 ± 11.40, and 65.61 ± 45.42, respectively. The average MELD and Maddrey scores were 14.13 ± 5.17 and 36.45 ± 29.63, respectively. The mean platelet counts, PDW, MPV, and PCT were 194.01 ± 178.82 × 109/L, 17.10 ± 1.21, 5.99 ± 0.96, and 0.14 ± 0.04, respectively. PDW >18 and MPV had a significant positive correlation with MELD scores. Only bilirubin and prothrombin prolongation were significant predictors of severe alcoholic hepatitis. The area under the curve was highest for PCT at 0.622 (P = .07; confidence interval = 0.500–0.743). Conclusions: Platelet indices appear to be significantly altered in alcoholic hepatitis, but they do not predict severe disease. Whether this inability to predict severe alcoholic hepatitis is due to coexisting illnesses such as pancreatitis, cirrhosis, and infection needs to be studied further.

Scrub typhus is a multisystem disease, and the respiratory system is commonly involved. Scrub typhus-related parkinsonism has been reported in three patients previously, and none of them underwent a lumbar puncture. Cerebral salt wasting is generally observed in vascular emergencies of the brain. We report a patient with acute parkinsonism and cerebral salt wasting syndrome, a combination of which has not been previously reported in scrub typhus. A 50-year-old farmer presented with an acute febrile illness of two weeks' duration and a one-day history of parkinsonism symptoms. His workup revealed hypoosmolar hyponatremia, increased urinary sodium excretion, hepatorenal and hematological dysfunction, and normal findings on cerebrospinal fluid examination. Clinical and biochemical improvement was noticed with the institution of doxycycline. Empirical doxycycline may be needed in patients with acute parkinsonism following an acute febrile illness in areas endemic for scrub typhus. Better biochemical facilities in resource-poor tropical countries would help in evaluating the etiology of hyponatremia due to infectious causes.

In order to mimic the loading of americium (Am) and curium (Cm) oxide in yttria stabilized zirconia, Zr0.70 [Y1-xNdx]0.30O1.85 (0.0 ≤ x ≤ 1.0) system was synthesized by solid state route and characterized by X-ray diffraction (XRD) and Raman spectroscopy. The entire system appeared single-phasic fluorite-type by XRD. However, Raman spectroscopy revealed the existence of tetragonal domains for the Nd-rich composition, Zr0.70Nd0.30O1.85 (x = 1.0). Bulk thermal expansion coefficient was found to increase with increasing NdO1.5 content in this series in the temperature range 298–1473 K. The heat capacity of sintered samples was measured by heat flux-type differential scanning calorimeter over the temperature range 313–713 K and it was observed to decrease with increasing Nd3+-content. Thermal conductivity values were determined from measured thermal diffusivity, temperature dependent density and specific heat capacity values. The thermal conductivity of Nd3+ stabilized zirconia was lower than yttria stabilized zirconia.

An effort was taken to carry our speciation study of uranium ion in technologically important cerate host Sr2CeO4 using time resolved photoluminescence spectroscopy. Such studies are not relevant only to nuclear industry but can give rich insight into fundamentals of 5f electron chemistry in solid state systems. In this work both undoped and varied amount of uranium doped Sr2CeO4 compound is synthesized using complex polymerization method and is characterized systematically using X-ray diffraction (XRD), Raman spectroscopy, impedance spectroscopy and scanning electron microscopy (SEM). Both XRD and Raman spectroscopy confirmed the formation of pure Sr2CeO4 which has tendency to decompose peritectically to SrCeO3 and SrO at higher temperature. Uranium doping is confirmed by XRD. Uranium exhibits a rich chemistry owing to its variable oxidation state from +3 to +6. Each of them exhibits distinct luminescence properties either due to f-f transitions or ligand to metal charge transfer (LMCT). We have taken Sr2CeO4 as a model host lattice to understand the photophysical characteristics of uranium ion in it. Emission spectroscopy revealed the stabilization of uranium as U (VI) in the form of UO66- (octahedral uranate) in Sr2CeO4. Emission kinetics study reflects that uranate ions are not homogeneously distributed in Sr2CeO4 and it has two different environments due to its stabilization at both Sr2+ as well as Ce4+ site. The lifetime population analysis interestingly pinpointed that majority of uranate ion resided at Ce4+ site. The critical energy-transfer distance between the uranate ion was determined based on which the concentration quenching mechanism was attributed to electric multipolar interaction. These studies are very important in designing Sr2CeO4 based optoelectronic material as well exploring it for actinides studies.

Thorium uranium oxide powder with uranium concentrations 10, 20, 30, 40, 50 and 70 mol% was prepared by gel combustion method. The sintering behaviour of the powders studied by dilatometry indicated that samples containing uranium up to 30 mol% had similar shrinkage behaviour with single step sintering. However, samples containing 40, 50 and 70% uranium followed two step sintering process. Though the air calcined powder shows two phase system beyond 30% uranium containing samples, sintering results into single phase system for samples containing up to 50% of uranium. The temperature programmed reduction-oxidation experiments showed that compositions containing up to 50-mol% of uranium show single reducible species throughout the temperature range. X-ray photoelectron spectroscopic studies of these sintered pellets showed presence of uranium in 6 + and 4 + oxidation states in these oxides. The experimentally determined heat capacities of solid solutions were found to have higher values than that of computed using Neumann–Kopp’s molar additivity rule.

Exploring the structural and thermophysical behaviour of Nd-Substituted ZrO2 is vital in context of matrices for minor actinide transmutation. Hence, phase relations have been studied in this system using high temperature sintered samples prepared by gel combustion route. Phase characterization of Zr1 − xNdxO2 − x / 2 (0.0 ≤ x ≤ 1.0) series was carried out using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). With increasing NdO1.5 content, the system evolved in the sequence of (a) monoclinic zirconia (b) mixture of monoclinic + cubic stabilized zirconia, (c) cubic stabilized zirconia (d) mixture of stabilized zirconia + pyrochlore (e) pyrochlore (f) mixture of pyrochlore + hexagonal Nd2O3 and (g) pure hexagonal Nd2O3. Lattice and bulk thermal expansion of few selected compositions were characterized by high temperature XRD (298–1273 K) and dilatometry (323–1673 K). Average coefficient of thermal expansion decreased with increasing NdO1.5 fraction in Zr1 − xNdxO2 − x / 2 series (x = 0.2, 0.3, 0.4, 0.5) solid solutions, which has been attributed to increasing order in cation sub-lattice resulting in overall increase in lattice stability. Thermal conductivity has been reported for a representative composition Zr0.8Nd0.2O1.90. Keywords: ZrO2-NdO1.5 binary system, Pyrochlore, XRD, Raman spectroscopy, Thermal expansion, Thermal conductivity

Improving functional properties of biopolymers for use as environment friendly packaging is an area of current interest. Biodegradable films with improved barrier and mechanical properties were prepared from methylated guar gum. Methylation resulted in structural modification of guar gum (GG) promoting greater crystallization thereby enhancing thermal stability towards decomposition. Reduction in radius of gyration (Rg), weight average molecular weight (Mw), and an increase in polydispersity index (PDI) were also observed due to methylation. Methylated guar gum (MGG) films exhibited 40% lower water vapor transmission rate (WVTR) as compared to control purified guar gum (PGG) films. Films prepared by partial replacement of PGG with MGG (10, 25, 50, 75 and 100% w/w) showed gradual improvement in percent elongation. The study gives an insight on the role of methylation in enhancing barrier and mechanical properties of GG based biodegradable films for possible application in food packaging.

India is developing thorium-based nuclear technologies with the aim to introduce them in its energy mix that is sustainable in the long term. Various reactor systems based on thorium fuel cycle are being developed. These include (i) thorium utilization in existing reactors (PHWRs), (ii) advanced heavy water reactor (AHWR), (iii) metallic-fueled reactors (fast/thermal), and (iv) molten salt reactor (MSR). Different fuel forms being studied include oxides/carbides, metallic alloys, and fluoride salts. Comprehensive information on the physicochemical properties of fuel is a primary input as required by reactor engineers and safety analysts to predict its performance under normal/off-normal reactor operation scenarios. The variable parameters essentially include temperature, composition, microstructure, and radiation field. A reliable database on thermophysical, thermochemical, and thermodynamic properties of fuel and related materials is therefore essential. This chapter presents an overview of R&D efforts in this direction carried out at Chemistry Group of Bhabha Atomic Research Centre (BARC). Important results and their implications in terms of fuel’s performance potential are highlighted. While understanding of thorium-based oxide fuels (Th-U MOX, Th–Ce MOX, and SIMFUELS) has attained reasonable maturity, exciting potential of thorium-based in metallic fuel and fluoride salt fuel is being unearthed with recent experimental work. Few results on thorium-based metallic alloys are also presented. To conclude, glimpses of research efforts on thorium-based fluoride salts for Indian molten salt breeder reactor (IMSBR) are outlined.

Strontium cerate (SrCeO3) exhibits proton conductivity in humidified atmosphere at elevated temperature. However this material is unstable in CO2 and H2O atmosphere. Thought its proton conductivity is lower than barium cerate (BaCeO3) there is scope to improve its stability, sinterability and ionic conductivity by substituting suitable cations at B-site. SrCe0.8-xZrxY0.2O3-δ (SCZY, with x = 0.0, 0.2, 0.4, 0.6 and 0.8) powders were synthesized by sol gel route. Lattice parameters were generated from powder XRD data and it was found that with increase in Zr content the cell volume reduces. Chemical stability of sintered SCZY samples was evaluated in 100% CO2 using TG-DTA up to 1173 K and also in boiling water. Zirconium doped samples exhibit enhanced chemical stability in presence of carbon dioxide and boiling water, with x ≥ 0.4 compositions having no effect of both the reactive gases. Proton conductivity of SCZY samples were measured in moist N2 atmosphere. Activation energy for proton conduction was also evaluated.

A simplified, highly reliable, cost effective high temperature (RT-1373 K) vertical dilatometer system, based on linear variable differential transformer (LVDT) has been designed, fabricated and tested for measurement of linear thermal dilation of solid samples. Unique features of this fully automated PC-controlled system are: simple design, fabrication from locally available components, ease of operation and maintenance, good temperature resolution (1 K), wide measurement range (±1 mm, with 100 nm resolution), microcontroller-based data acquisition hardware and a simple windows-based software. The system has been tested for its performance using NIST sapphire reference and high purity metals including aluminum and nickel. Overall accuracy of the system for measurement of linear thermal dilation is within 3% of the reported values for NIST sapphire. The system is a good example of a simple experimental facility for routine thermal expansion characterization of solids. Combination of simplified design, automation and reliable performance without using sophisticated instrumentation/control systems makes it a novel cost effective thermo-analytical equipment, which can be put to widespread routine usage for researchers, academy and small/medium-scale industries.

Design, fabrication and performance evaluation of a low temperature semi-adiabatic heat-pulse calorimeter for heat capacity measurement on small samples from 10 to 300 K has been presented. Automation has been brought in by indigenously developed data acquisition system (DAS) in ‘C’ language using LabWindows/CVI platform. A simple algorithm for identifying the attainment of thermal equilibrium in the calorimeter has been proposed and successfully implemented. Several useful sub-routines, enabling uninterrupted operation of calorimeter and continued measurement of reliable heat capacity data over the operational temperature range have been discussed. Performance of the calorimeter has been tested with oxygen-free high conducting copper (OFHC) and two other materials namely potassium di-hydrogen phosphate (KH2PO4) and Fe3PO7. Comparison of results with reported values have shown overall ±2% accuracy.

RE6UO12(s) (RE = La, Pr, Nd, Sm) was synthesized by citrate-nitrate combustion method. The synthesis condition for Pr6UO12(s) was optimized. Nonstoichiometry in these rare earth uranates in argon atmosphere was analysed using various techniques like thermogravimetry (TG), X-ray photo electron spectroscopy (XPS), chemical analysis and electrical conductivity measurements. Thermal expansions of RE6UO12(s) (RE = Pr and Sm) was studied in the temperature range 298–1273 K by high temperature X-ray powder diffractometry and compared with that of similar rare earth compounds reported in the literature. Heat capacity of RE6UO12(s) (RE = La, Pr, Nd, Sm) was measured by differential scanning calorimetry in the temperature range 300–870 K. Enthalpy, entropy and Gibbs energy functions of these compounds were computed from the measured heat capacity data.

A simple, cost effective, surfactant free and scalable synthesis of rhombohedral In2O3 (rh-In2O3) nanostructures with controllable size and shape has been developed under ambient pressure by thermal dehydration of InOOH nanostructures. The InOOH nanostructures have been prepared by solvothermal reaction between indium nitrate hydrate with tetramethylammonium hydroxide (TMAH) in anhydrous methanol at 140 °C without any surfactant. The structure and morphology of the nanostructures have been characterized in detail by X-ray powder diffraction (XRD), Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM). The studies reveal that highly crystalline nanostructures of InOOH and rh-In2O3 with rice-grain type morphology are formed. The optical properties of the InOOH and rh-In2O3 nanostructures have been explored by UV-visible diffuse reflectance spectroscopy (UV-DRS) and room-temperature photoluminescence (PL) studies. The direct band gap of as-synthesized InOOH and rh-In2O3 nanostructures was estimated to be 3.75 and 2.95 eV, respectively, from the diffuse reflectance absorbance spectra. Both InOOH and rh-In2O3 nanostructures show intense blue emission under UV excitation which is attributed to the presence of oxygen vacancies. The thermal stability of the rh-In2O3 phase has been studied by differential scanning calorimetry (DSC), differential thermal analysis (DTA) and dilatometry of the as prepared sample. The potential of InOOH and rh-In2O3 nanostructures as photocatalytic materials for hydrogen generation from water/methanol (2 : 1) mixtures under UV/vis irradiation has also been evaluated for the first time.

Reliable experimental evaluation of thermal conductivity of nuclear-grade uranium over a wide temperature range from 298 K to 1273 K, encompassing both of its solid-state allotropic phase transformations has been carried out for the first time using thermal diffusivity and linear thermal expansion data. Temperature dependence of both diffusivity and expansivity showed abrupt break at both the phase transitions namely, orthorhombic (α-phase) to tetragonal (β-phase) at 948 K and tetragonal (β-phase) to cubic (γ-phase) at 1051 K. Thermal conductivity also increases abruptly upon uranium undergoing structural modification from ambient temperature orthorhombic phase to high temperature cubic phase. Observed differences in results obtained in present investigation from those reported in literature have been explained on the basis of non-metallic impurity contents and inherent structural anisotropy of uranium. It has been suggested that structural anisotropy, which strongly affects metal’s microstructure; also notably influences the heat transport properties. High temperature body centred cubic phase (BCC) of uranium shows very high heat conductivity (44 W/m.K at 1075 K), which affirms the advantage of cubic-phase uranium alloys as potential metallic nuclear fuel. Presented results will be highly useful for development of uranium-based metallic alloy fuels.

A 37-year-old plumber was admitted with acute abdominal pain of 4 days’ duration that was associated with nausea, vomiting and constipation. He had consumed ~120 g ethanol/day for the last 7 years and had been admitted for alcohol withdrawal syndrome 5 months ago. On examination in the

In the present study, influence of local environment around Th4+ ions in the precursor gel on the powder characteristics of combusted product (ThO2) is investigated in detail. Partial crystallization of Th4+ complexes having different number of glycine and NO3− species in glycine-thorium nitrate aqueous gel has been confirmed by DSC and SAXS studies. Further, combining SAXS and FT-IR results with existing speciation studies, it is inferred that, varying concentrations of mono- and hexanuclear Th4+-glycine-NO3- complexes are formed in the precursor gel depending upon the fuel to oxidant ratio (F:O). Lower F:O values lead to predominance of hexanuclear Th4+-glycine-NO3- complexes with excess NO3− ions in its vicinity while higher F:O value (F:O = 1.25) results in predominant formation of monocular Th4+-glycine-NO3- complexes. Combustion of gel consisting of mononuclear complexes leads to smaller ThO2 crystallites as compared to hexanuclear complexes as the Th4+--Th4+ distances are larger in the former compared to the latter. The above mentioned complex species are responsible for the observed bimodal crystallite size distribution in nanocrystalline ThO2 powder prepared upon combustion of gel precursor.

Diamond, with its name derived from the Greek word adamas (meaning unconquerable/invincible ), is a unique material with potential use in several applications. In nature, it occurs deep down in the Earth's crust in regions of high temperatures and high pressures with limited availability and nonreproducible quality. It is also synthesized industrially using high-temperature, high-pressure methods or chemical vapor deposition (CVD) methods. CVD methods in particular have excellent control over the quality of diamond, and it is possible to synthesize pure/doped diamonds using simple gaseous precursors like H 2 and suitable carbon source (CH 4 , CO 2 , C 2 H 4 , etc.) at low pressures. Both single crystals and polycrystalline diamonds of desired quality can be routinely synthesized. CVD method has therefore brought about a revolution in this field and expanded the development of diamond-based technologies. With its inherent physicochemical properties, diamond is an excellent host matrix for radiation detection purposes. It offers the best performance potential especially under extreme operational conditions such as high temperatures, corrosive environments, intense radiation fields, fast radiation events, etc. CVD diamonds have immense application in this area. The present chapter outlines the potential of CVD diamond as a host matrix for radiation detection under extreme conditions and gives description of diamond-based alpha particle detectors for use in highly corrosive chemical environments, with special reference to estimation of actinides in acidic liquids. Results obtained in our research group on development of such detectors are also summarized. Essential factors that influence performance of diamond-based radiation detectors and possible methods to address them are also detailed.

Acute pyelonephritis is a common renal manifestation in patients with diabetes. A 52-year-old diabetic lady presented with loin pain, dysuria, and fever and urinary incontinence that had begun seven and three days prior to presentation respectively. She was treated with escalating spectra of intravenous antibiotics without improvement. Urine and blood cultures were sterile, while radiological investigations were suggestive of pyelonephritis. Mild hepatic dysfunction prompted consideration of scrub typhus and she improved with empirical doxycycline. Scrub IgM was later confirmed to be positive. In conclusion, local prevalence of systemic infections such as rickettsioses should always be considered in diabetics with fever, even if symptoms and signs otherwise suggest typical diabetes-related infections. We, therefore report a case of acute pyelonephritis caused by scrub typhus which has not been previously described in English medical literature.

Background: The World Health Organization in 2009 revised categories of dengue fever severity into classes A, B, and C based on the presence or absence of warning signs. The quantum of oral and intravenous fluids (IVF) in hospitalised patients with Group B (warning signs) has, to our knowledge, not been studied. Oral fluids in hospitalised patients and monitoring administration with the help of patients’ relatives have not been assessed. Methods: Consecutive patients with dengue fever and warning signs were studied for 48 hours after hospitalisation. Patients were asked to consume 4-5 l of fluids. Maintenance and bolus IVF were administered depending upon the presence of compensated or hypotensive shock. Intake and urinary output were monitored by the patient’s attendant. Total fluids (oral and intravenous) were divided by a number of anthropometric measurements. The significance of warning signs, compensated and hypotensive shock, thrombocytopenia, bleeding episodes and the need for transfusions, and organ impairment were considered in relation to the total amount of fluids received daily. Results: In total, 43 patients were studied. Patients with obesity and hypotensive shock received significantly more fluids on Day 1; taller patients and those with tachycardia, higher haematocrit and elevated creatine kinase correspondingly received more on Day 2. Hypotensive shock was significantly correlated with fluids/BSA, fluids/weight and fluids/BMI, while laboratory parameters correlated most strongly with fluids/BMI. Conclusions: Most adults with dengue and warning signs seem to require >100 ml/kg/day of fluids during their stay. Advising a similar amount of fluids at home during epidemics may further reduce the need for admissions. Participation of patients and their relatives in the bedside management of fluid administration may go a long way in preventing morbidity and mortality. Adults probably need a better anthropometric measurement to decide on the quantum of fluids to be given.

The magnitude of the optical sheet conductance of single-layer graphene is universal, and equal to e 2/4ħ (where 2πħ = h (the Planck constant)). As the optical frequency decreases, the conductivity decreases. However, at some frequency in the THz range, the conductivity increases again, eventually reaching the DC value, where the magnitude of the DC sheet conductance generally displays a sample- and doping-dependent value between ∼e 2/h and 100 e 2/h. Thus, the THz range is predicted to be a non-trivial region of the spectrum for electron transport in graphene, and may have interesting technological applications. In this paper, we present the first frequency domain measurements of the absolute value of multilayer graphene (MLG) and single-layer graphene (SLG) sheet conductivity and transparency from DC to 1 THz, and establish a firm foundation for future THz applications of graphene.

Aliovalent Sc 3+ doped pyrochlores NdGdZr 2− x Sc x O 7− δ (0.0 ≤ x ≤ 0.15) have been prepared by gel-combustion method followed by high temperature sintering. Detailed structural characterization of these compounds has been carried out using X-ray diffraction and Raman spectroscopy, which together have established the retention of pyrochlore structure of these compositions till x = 0.15 Sc 3+ incorporation. Both X-ray diffraction and Raman results have also indicated the presence of local lattice distortion with net cell contraction upon Sc 3+ incorporation in these solid solutions. Micro structural studies have revealed highly dense end products with uniform grain distribution and homogeneous compositions at grain size level. Ionic conductivity characterization of system been carried out from 473 to 573 K. A significant improvement in the total ionic conductivity of this series has been observed which has been explained in terms of additional oxygen vacancies created upon Sc 3+ incorporation and enhanced lattice disorder.

Ba1−xSrxMoO4 (x = 0, 0.18, 0.38, 0.60, 0.81, 1) solid-solutions were synthesized by complex polymerization method. The solid solutions were characterized using X-ray diffraction (XRD) and the Raman spectroscopy. Heat capacity measurements on Ba1−xSrxMoO4(s) were performed with heat flux-type differential scanning calorimeter in the temperature range of 140–870 K. The measured heat capacity values were used to calculate different thermodynamic functions such as enthalpy increment, entropy and Gibbs energy functions. Thermal expansion behavior of Ba1−xSrxMoO4(s) (x = 0, 0.6 and 1) were investigated in the temperature range 298–1273 K by high temperature X-ray diffraction (HTXRD). The specific heat and average volume thermal expansion coefficient of Ba1−xSrxMoO4(s) was found to increase with increase in concentration of strontium. The average volume thermal expansion coefficient of Ba1−xSrxMoO4(s) (x = 0, 0.6 and 1) was found to be 25.59 × 10−6, 33.86 × 10−6 and 34.37 × 10−6 K−1 respectively.

Detailed structural and electrical investigations were carried out on a GdSc1–xInxO3 (0.0 ≤ x ≤ 1.0) series. The solubility of In3+ in GdScO3 could be increased by 20 mol % by changing the synthesis route. GdScO3, a technologically important dielectric material, could be synthesized at a temperature as low as 850 °C. An orthorhombic modification of GdInO3 could be stabilized by 20 mol % Sc3+ substitution, which is otherwise known to prefer hexagonal polymorphs. Nonpreference of trigonal bipyramidal coordination by Sc3+ led to the existence of a very narrow biphasic field. A very interesting observation is the existence of same nominal composition (GdSc0.1In0.9O3) in two different modifications (orthorhombic and hexagonal) in the biphasic region. Careful Raman spectroscopic studies highlighted the fact that the local polyhedral coordination of the Sc3+/In3+ undergoes an abrupt change as the phase relations evolve from orthorhombic to hexagonal phase field. The trend in the net shrinkage observed on the pow...

Bunsen reaction is an important step of sulfur–iodine cycle for hydrogen production from thermochemical splitting of water. Polyiodide species generated during the separation process need to be identified for complete understanding of the mechanism involved. Speciation of these polyiodide species formed during Bunsen reaction can lead to better understanding of kinetics of the process. HIx species formed have been analyzed using UV–visible and Raman spectroscopic techniques. Peak corresponding to HI3 species have been ascertained and their conversion to higher HI5, HI7 …… species has been observed.

While the potential for high mobility printed semiconducting nanotube inks has been clear for over a decade, a myriad of scientific and technological issues has prevented commercialization and practical use. One of the most challenging scientific problems has been to understand the relationship between the pristine, individual nanotube mobility (known to be in the 10,000 cm(2)/V·s range) and the as-deposited random network mobility (recently demonstrated in the 100 cm(2)/V·s range). An additional significant scientific hurdle has been to understand, manage, and ultimately eliminate the effects of metallic nanotubes on the network performance, specifically the on/off ratio. Additional scientific progress is important in understanding the dependence of nanotube length, diameter, and density on device performance. Finally, the development of ink formulations that are of practical use in manufacturing is of paramount importance, especially with regard to drying time and uniformity, and ultimately, the issue of scalability and cost must be addressed. Many of these issues have recently been investigated from a phenomenological point of view, and a comprehensive understanding is beginning to emerge. In this paper, we present an overview of solution-based printed carbon nanotube devices and discuss long-term technology prospects. While significant technical challenges still remain, it is clear that the prospects for the use of nanotube ink in a myriad of systems is feasible given their unmatched mobility and compatibility with heterogeneous integration into a variety of applications in printed and flexible electronics.

The paper details the results of sintering kinetics studies conducted on nanocrystalline Mo–30 wt.% W alloy powders prepared through mechanical alloying route. Both, constant rate of heating method as well as Stepwise Isothermal Dilatometry (SID) technique were used for studying the sintering kinetics. Measured step isothermal shrinkage data were analyzed by Mekipritti-Meng method. The shrinkage data was found to fit well with the rate equation proposed in this method and its validity was established for mechanically alloyed systems. Kinetic parameters were evaluated and sintering was found to occur through two major mechanisms operative successively, which are grain boundary diffusion and lattice diffusion with corresponding energies of activation as 230 kJ/mol and 480 kJ/mol, respectively. The results have been well supported by micro structural evaluation of specimens at different stages of sintering.

Summary: We report an unusual case of varicella zoster in a 19-year-old, who presented with persisting fever even after her lesions began forming scabs. Fever workup for secondary complications was negative. A re-examination revealed an axillary eschar. She recovered completely with doxycycline. This report suggests the importance of keeping in mind, epidemiological data of common diseases in the locality, as well as the significance of a thorough physical examination in patients with fever. Keywords: Scrub typhus co-infection, Rickettsial rash, Varicella zoster

In this article, the authors review the progress toward carbon nanotube based electronics and consider the implications for application of nanotubes in analogue RF devices and RF system applications as well as recent prospects in printed electronics, especially printed RFID tags. The author also points out that nanowire devices are also starting to show similar performance in the RF domain, with similar manufacturing challenges.