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In the present work, a micro-electro-mechanical system (MEMS)-based electrostatic micromotor is designed and fabricated. Finite element analysis is done and various parameters affecting the torque are studied. Maximum torque is achieved at 120° phase angle. The effect of change in voltage, micromotor height and frequency is analysed and discussed. UV-SLIGA, a microfabrication technique, is used for the fabrication of electrostatic micromotor of height 30µm and higher. UV lithography is conducted by both positive AZ P4620 and negative (SU-8 10 and SU-8 2150) photoresists. Copper (Cu) is used as a sacrificial layer to release the rotor (the movable part) of the electrostatic micromotor. Electroformed nickel (Ni) is used for making stator, rotor and axle, whereas chromium (Cr) is used as a seed layer. The micromotor is fabricated with a stator-rotor pole having configuration ratio of 3:2. The gap between the rotor and axle is 20 µm. Wet chemical etching is used to etch the deposited metal layers (Cr, Ni and Cu). Challenges such as the adhesion between the photoresist mould and substrate, cracks, seepage and misalignment are faced during the microfabrication. These challenges are overcome by optimizing the various parameters. The fabrication of electrostatic micromotor is done successfully and the results are discussed in the article.

Metal-assisted chemical etching (MaCEtch) has recently emerged as a promising technique to etch anisotropic nano- and microstructures in silicon by metal catalysts. It is an economical wet chemical etching method, which can be a good alternative to deep-reactive ion etching (DRIE) process in terms of verticality and etch depth. In the present study, gold is used as a metal catalyst and deposited using physical vapour deposition. It has already been demonstrated that (100) p-type Si wafer can be etched with vertical and smooth side walls. Effects of varying concentrations of etchant constituents and various other parameters, that is, porosity of deposited Au, surface contaminants, oxide formation, metal catalyst, etching time, role of surface tension of additives on the etch depth and surface defects are studied and discussed in detail. By increasing the hydrofluoric acid (HF) concentration from 7.5 M to 10 M, lateral etching is reduced and the microstructure’s width is increased from 17 µm to 18 µm. Porous defects are suppressed by decreasing the hydrogen peroxide (H2O2) concentration from 1.5 M to 1 M. On increasing the etching time from 30 min to 60 min, the microstructures are over-etched laterally. Smoother side walls are fabricated by using the low-surface-tension additive ethanol. The maximum etch depth of 2.6 µm is achieved for Au catalyst in 30 min. The results are encouraging and useful for the development of vertical comb-drives and Micro-Electro-Mechanical Systems (MEMS).

A fuel with parameters such as high energy density, lower viscosity, and freezing point is desirable to be used in missile aircrafts jets at higher altitudes. In this regard, exotetrahydrodicyclope...

Encapsulation of noble metals inside the zeolite cage has attracted much attention in the area of catalysis due to unique properties, i.e., shape selectivity, higher activity, and product yield. In the combined work, encapsulated Platinum (Pt) inside the sodalite cage combined with sulfided nickel and molybdenum supported on silica-alumina (NiMo(S)/SiO2-Al2O3) is used to improve the catalyst hydrogenation function by providing spillover hydrogen to the nearby active sulfided NiMo sites. Encapsulation ensures the protection of the noble metal sites from poisoning due to the sulfur-containing compounds. They have a higher hydrodynamic diameter than that of the sodalite window cage. Experimental results showed platinum encapsulated sulfided nickel and molybdenum supported on silica-alumina (Pt@SOD-NiMo(S)-SiO2-Al2O3) had a substantial effect on the product composition, yield, and hydrogen consumption compared with the conventional NiMo(S)/SiO2-Al2O3 catalyst for the hydroconversion reaction of jatropha oil to produce carbon–neutral green fuels. Sustainable aviation fuel with lower aromatics and naphthene content (600 h of the run, whereas state-of-the-art reported catalyst Pt@SOD-NiMo(S)-ZSM-5 had limitations in terms of catalyst life (stable activity only for 350 h).

In this work, copper oxide (CuO) nanoparticles were synthesized at different temperature using chemical co precipitation method at room temperature. The synthesized copper oxide nanoparticles were mixed with activated charcoal powder to make nanocomposite for its application as electrodes material in ultracapacitor. Electrodes formed by synthesized nanocomposite at 600 OC show superior performance, which has been used as the optimized temperature for nanocomposite synthesis. Also nanoparticle and charcoal mass ratio1:1 was found to be optimum for electrochemical performance. The synchrotron X-ray diffraction (SXRD) pattern confirms the monoclinic structure of the synthesised CuO nanoparticles. Electrochemical performances of the synthesised nanocomposite electrode and prepared supercapacitor cell were studied using cyclic voltammetry, a.c. impedance spectroscopy and charge discharge methods with 1 M NaOH as an electrolytes. The specific capacitance of the fabricated supercapacitor cell A is constant upto 2000 cycles at 100 mV cm−2.

CO2 reduction is an attractive way for the production of sustainable environment-friendly chemicals. Using the density functional theory employed by DMol3, we calculated the electronic properties of α-sulfur-modified surface of TiO2 (111). We report α-sulfur-TiO2 composite material for selective CO2 reduction to methanol. The α-sulfur-TiO2 catalyst showed higher adsorption for CO2 molecule (reactant) and lower adsorption for methanol (product) as compared to TiO2 catalyst. The introduction of the α-sulfur molecule in the TiO2 catalyst leads to redistribution of the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO). The DFT studies showed that the α-sulfur-TiO2 catalyst reduced the band gap to 2.06 eV from 2.88 (α-sulfur) and 3.2 eV (TiO2). The experimental study was done using photoelectrochemical CO2 reduction. The sulfur-TiO2 catalyst showed higher methanol production (17 mM/h) under visible light as compared to α-sulfur catalyst (8.5 mM/h).

A High Aspect Ratio (HAR) electrostatic comb-drive microactuator of polymethyl-methacrylate (PMMA) is designed to deliver nearly 40 µm uniaxial displacement at 25 V DC. The HAR comb-drive microstructures are fabricated via one-step X-ray lithography (OXL). Polyimide-Au X-ray mask is fabricated and used to pattern 200 μm, 500 μm and 800 μm thick PMMA by deep X-ray lithography (DXRL), followed by drying/release and selective metallization for the development of HAR electrostatic microactuator. The release was optimized with the help of various low-surface-tension liquids. 200 μm and 500 μm thick microstructures were successfully released whereas, 800 μm structures could not be released due to the higher depth and associated capillary force. In addition, non-uniform distribution of Au on the side walls of overlapped region of comb fingers, during metallization, resulted in uneven distribution of electrostatic force followed by short-circuiting of HAR (i.e. 40) microactuator. These are the potential issues in the fabrication of HAR microstructures and devices by OXL and discussed in details in this paper.

Objectives This study aimeded to examine acute and late effects of five consecutive sessions of Swedish massage on hamstring flexibility and agility of players.Methods: Arandom sample of 34 female players having bilateral tight hamstrings [passive straight leg raise ≤70° and active knee extension test ≥ 30°] was randomly allocated to two equal groups. Study design involved 7 minute massage given on each posterior thigh for 5 continuous days; followed by 5 days of no massage. Experimental group received classical Swedish massage whereas control group received only superficial stroking. Outcome measures were Passive straight leg raise [PSLR], Active knee extension test [AKET], Passive knee extension test [PKET], Back saver sit and reach test [BSSR] for flexibility and 5-0-5 change of direction test for agility measured pre and post intervention on each days of massage and also on 10th day. Two way ANOVA with post hoc t-test was the tool of statistical analysis with significance level 0.05.Results: Significant [p ≤ 0.05] post intervention increase in all parameters of flexibility was observed each day in experimental group within PSLR (8%–12% ↑), AKET (10%24% ↓) and PKET (12%–30% ↓) and highly significant (p ≤ 0.001) increase on 5th and 10th day in BSSR (4%–21% ↑) for both legs. Pre and post intervention values for control group were not significantly different. No significant changes were observed in agility performance of both groups.Conclusion: Swedish massage of posterior thigh appears to acutely increase flexibility of hamstrings in female athletes, which persisted for 5 days even after cessation of massage.

Garlic, as well as several natural food ingredients such as basil, ginger, turmeric, cinnamon, clove, pepper etc., has long been traditionally used as routine anti-viral and anti-bacterial remedy. Allyl methyl sulfide (AMS) is reportedly a persistent main active metabolite component of allicin after garlic ingestion accounting for at least 90% of the allicin consumed. Several studies have reported the presence of AMS in organs such as lung, kidney etc. and body fluids such as mucous, and blood-plasma. Glycoproteins of enveloped viruses are actively involved in viral pathogenesis. N-acetylneuraminic acid (sialic acid) and N-Acetylglucosamine, are some of the vital amino acids involved in several viral infections using glycoproteins via glycosylation. Simulations studies based on First-principles density functional theory show that these amino acids attach with AMS, and the reactions are thermodynamically spontaneous (ΔG and ΔS negative are at 310.15 K as well as lower and higher temperatures). Further, phospholipid phosphatidylethanolamine (a component of some viral envelops) also attaches readily with AMS and the reaction is spontaneous. AMS molecules attachment with viral phospholipids and amino-acids involved in viral infection would denature the virus and prevent its attachment to the host cell. Communicated by Ramaswamy H. Sarma.

The correlation of several defects and optical and magnetic properties with Fe content in Zn1−x Fe x Al2O4 (0.01 ≤ x ≤ 0.40) nanocrystals has been scrutinized through X-ray diffraction, O K-edge X-ray absorption near-edge structure, FT–IR, diffuse reflectance, photoluminescence and electron spin-resonance spectroscopies, and vibrating sample magnetometry. Increasing Fe content causes elongation in the octahedral units of the lattice, accompanied by distortion in the octahedral coordination. Fe introduces non-radiative centres in the forbidden gap, thereby tuning the band gap from 4.37 to 3.88 eV and eliminating emission in the visible region. Zn vacancies are found to tail off, while {\rm Fe}_i^{\bullet \bullet \bullet}, {\rm Al}_{\rm Zn}^\bullet and FeAl × antisite defects increase in concentration with increasing Fe content. Inhomogeneous broadening of spin-resonance signals infers strong spin-lattice interactions of Fe3+ ions at distorted octahedral and non-symmetric tetrahedral sites. A transition is observed from paramagnetism to superparamagnetism at higher Fe concentrations. A visual colour change from pearly white to orange–brown is observed in Zn1−x Fe x Al2O4 nanocrystals with increasing Fe content, revealing its potential candidature for pigments in the paint and dye industries.

We report high-temperature synchrotron X-ray diffraction (SXRD), magnetization, and current-voltage (I-V) characteristics for the samples of Co2.75Fe0.25O4 ferrite. The material was prepared by chemical reaction of the Fe and Co nitrate solutions at pH ∼ 11 and subsequent thermal annealing. Physical properties of the samples were measured by cycling the temperature from 300 K to high temperature (warming mode) and returning back to 300 K (cooling mode). The lattice structure showed sensitivity to high measurement temperatures. Magnetization curves showed a defect-induced ferromagnetic phase at higher temperatures and superparamagnetic blocking of the ferrimagnetic particles near to 300 K or below. Electrical conductivity exhibited a thermal hysteresis loop at higher measurement temperatures. The samples exhibited new form (not studied so far) of surface magnetism in Co rich spinel oxides and irreversibility phenomena in the lattice structure, magnetization, and conductivity on cycling the measurement temperatures.

Home health care services are an extension of the hospital services provided in the home of the patients. These services cover systematic nursing care and professional caregiving to chronically ill and bedridden patients. There are a substantial number of such patients who are immobile or suffer from chronic illnesses such as dementia, cancer, hypertension and similar ill-health conditions where constant care is necessary. The home care services, therefore, range from basic support for conducting the routine daily activities of dressing, grooming, ambulation and preparing prescribed meals to complex nursing services such as feeding through a nasogastric tube, catheter change, administering injections, medications and tending to tracheotomy. There is a growing need for the successful retention of people working in home care. This article provides vital insights into the job experiences of nurses and General Duty Assistants, which have been provided through qualitative findings of the study. Semi-structured interviews were conducted among 40 nurses and 40 General Duty Assistants. Open-ended questions were used to obtain the views of participants, and three primary relationships affecting their emotional state were identified. Relationship with the patient, family members of the patient and agency supervisor were studied. The participants were asked to describe the reasons why they do their jobs and the challenges they face while working in home care. Short-term and long-term recommendations were formulated based on the participant’s narratives.

Doping the fuel with fuel-borne catalysts is an economical and inventive option for reducing the emissions from conventional fuel. The present investigation explores the effect of Au/CeO2 doping in diesel fuel on combustion and emission characteristics of the compression ignition (CI) engine. Experiments were performed on a direct injection four-stroke water-cooled diesel engine (Kirloskar TV1) at varying engine loads. Results indicated that Au/CeO2 doped diesel enhanced the combustion process and progressively increased the in-cylinder pressure at each tested load condition. Au/CeO2 doped diesel fuel was found to be effective in reducing NO and hydrocarbon emissions. The particulate number concentration was decreased in nucleation mode while it increased in accumulation mode with Au/CeO2 doped diesel fuel.

From low-temperature Synchrotron X-ray diffraction, a precise thermal characterization of octahedral distortions in single phase Ruddlesden-Popper Ca3Mn2O7 is performed. Highly sensitive close-steps temperature dependences of Mn-O-Mn bond angles connecting MnO6 octahedra clearly reveal signature of the spin-ordering in the system. Spin-lattice coupling is thus established via the structural distortions responsible for evolution of the magnetic state. Further, temperature anomalies observed here in volume and polarization-measure of the unit cell highlight the interplay between spin, lattice and charge degrees of freedom. Dipole-relaxation characteristics examined under applied magnetic field consistently corroborate the concurrent magnetic and structural changes, in terms of genuine and intrinsic magneto-dielectricity.

Electronic and crystal structure studies are presented to describe the role of intersite and onsite interactions for antiferromagnetic ordering in CeAg2Ge2. The crystal structure showed a prominent magnetovolume effect with anomalous negative thermal expansion at low temperature as a consequence of itinerant electron magnetism. The direct hybridization gap with a V-shaped band observed in the angle resolved photoemission data at room temperature, indicates that spin polarized quasiparticle states exist in the gapped region. Valence band broadening and enhanced localization effects at low temperature indicate strong hybridization of the valence orbitals of Ce atoms with the near neighbor Ge atoms. We find that the intersite interaction between the Ce atoms at high temperature stabilizes the onsite interaction at low temperature that leads to the spin density wave type antiferromagnetism in CeAg2Ge2.

We have thoroughly investigated the crystal structure of ice evolved from super cooled water confined in MCM-41 cylindrical nano pores through a synchrotron-based X-ray diffraction (XRD) technique for two different levels of pore filling. A rigorous analysis of XRD data shows that the nucleation dynamics and the structure of nucleated ice highly depend on the level of pore filling. In the nearly fully hydrated pores, ice crystallites start nucleating inside the pores below 240 K and creep out of the pores to form bulk crystals having crystalline structure of a mixed phase of hexagonal and cubic forms. In the partially hydrated pores, on the other hand, ice crystals cannot creep out of the pore crossing the energy barrier. The crystalline ice particles remaining inside the cylindrical pore show a short range "cubic rich" structure. The "pure cubic" phase has not been identified at either of the pore fillings in these 2.5 nm average size pores. A large fraction of water inside the pores remains in the super cooled liquid phase even at 180 K. This observation is relevant for understanding the ice nucleation through the pore condensation and freezing mechanism, which is a major pathway for the formation of cirrus clouds in the upper atmosphere.

The controlled incorporation of defect species in amorphous oxide (AO) for regulating charge transport properties is highly demanding and challenging, especially for resistive switching (RS) memories. Here, we use pulsed electron beam deposition technique to engineer the growth of AO films, which show a large decrease (∼33%) in the t2g–eg gap. Our collective experiments and density functional theory (DFT) based ab initio simulations reveal the presence of undercoordinated TiO5 units, causing a decrease in the t2g–eg gap. Further, the importance of TiO5 in facilitating excess electron localization is demonstrated, showing an evolution of a broad defect band within the energy gap. The origin of this band (singly charged oxygen vacancy) is resolutely established by X-ray photoelectron spectroscopy and electron paramagnetic resonance measurements and is also supported by calculated partial charge density and Bader charge analysis. The preeminence of singly charged oxygen vacancies cause a low-current level (u...

A comparative microstructural study of as sintered and rubbed surfaces of BaTiO3 (BTO) ceramic pellet has been carried out using lab (8 keV Cu-Kα) as well as synchrotron (8–19 keV) based powder x-ray diffraction (XRD) at room temperature. These studies show a drastic change in the surface-microstructure of the BTO ceramics. Just a minutes rubbing of the BTO ceramics on a rough surface causes broadening of diffraction peaks. Nearly 3-times increase in the peak width and ∼ 3-times increase in integrated peak intensity of (00l) type peaks has been observed. The changes were analyzed as rubbing induced (00l) texturing and occurrence of anisotropic strain with maxima along [00l]. High temperature XRD studies reveal that for the strained BTO grains, the tetragonal to cubic transformation does not initiates at the proper TC ∼120 °C and does not complete even at temperatures ∼ 350 °C, which is ∼ 3 times the normal TC. About 20% of the tetragonal phase still remains untransformed. These features have been attributed to the formation of strain-glass phase at the rubbed surface of the BTO ceramics.

The Cr doped hematite (α-Fe1.4Cr0.6O3) system has been prepared by chemical route. The chemical routed sample has been thermally annealed at different temperatures in the range 800–1000 °C to study modified lattice structure and magnetic spin order. The present Cr doped hematite samples do not exhibit Morin transition, a typical temperature that marks spin orientation from in-plane spin to out of plane directions in hematite system. A distinct change in magnetic properties has been seen by increasing the annealing temperature. The sample prepared by annealing at 800 °C showed superparamagnetic blocking of particles below 38 K. Ac susceptibility data have been used to study the mechanism of spin dynamics around the blocking temperature. Such blocking behaviour of particles is not observed in the samples annealed at 900–1000 °C. The modified spin order in the samples has been understood by using core-shell model of antiferromagnetic particles. Mossbauer spectra of the samples have confirmed a transformation of the spin order with the increase of annealing temperature and support the features observed from dc magnetic measurements.

Photo-electrochemical properties of fluorine-doped tin oxide (FTO)/nickel oxide-nickel (Ni0.98Si0.02O2-Ni) with isolated Si sites are discussed. The Ni0.98Si0.02O2-Ni photo-electrocatalyst without any noble metal was prepared using a one-step chemical reduction precipitation method. Photo-electrochemical properties were investigated by cyclic voltammetry and chronoamperometry techniques in aqueous alkaline solution at pH 8.0. The photo-electrochemical response of the catalyst showed sensitivity to visible and UV light. The catalyst produced hydrogen from water at a rate of 0.5 mmol g−1 h−1 with the reduction of CO2 into CO under visible light in the absence of any light sensitizer or a noble metal. The metallic Ni amount in the catalyst system was optimized to obtain the best photo-electrocatalyst. The first principle DFT study showed that the incorporation of Si sites allowed absorbance of visible light. The catalyst was characterized by powder x-ray diffraction (PXRD), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma- atomic emission spectroscopy (ICP-AES), Brunauer–Emmett–Teller (BET), cyclic voltammetry, and chronoamperometry. The products were analyzed by gas chromatography- thermal conductivity detector (GC-TCD).

The thermoluminescence material, CaSO4:Dy, is widely used for the dosimetry of ionizing radiation due to its high sensitivity, low fading and wide dose range from μGy to few tens of gray. However, its application is limited at high doses due to non-linear and saturation effects. In this paper, X-ray Absorption Near Edge Structure (XANES) studies at the Dy L3-edge have been carried out on CaSO4:Dy discs exposed to gamma doses in the range 0–1000 Gy. The results show an increase in white line in XANES spectra with gamma dose. Structural change in CaSO4:Dy also has been studied using X-Ray Diffraction (XRD) and has found no structural change up to 1000 Gy. The study indicates that XANES can be used as an alternative dosimetry technique and is useful in the evaluation of absorbed dose in the case of accidental exposure to high radiation in a radiation facility or during a radiological accident.

In this report, we propose magnetically separable porous nickel oxide nanostructure with uniform Ni distribution having the large surface area and atomically dispersed Si sites for enhanced hydrogen production from organic waste. The catalyst showed ten times higher production rate from volatiles during carbonization of organic waste and coal than that in the absence of the catalyst. The reduced Ni/NiO catalyst yielded two times higher hydrogen production compared to the traditional Ni/Al 2 O 3 catalyst. The highest yield of hydrogen over reduced Ni/NiO was 32 g/kg feed at 600 °C in fixed bed reactor via pyrolysis-reforming of bagasse. The Ni/NiO showed far more efficient recyclability compared to traditional Ni/Al 2 O 3 . The economic aspect of the Ni/NiO catalyst was compared with the Ni/Al 2 O 3 catalyst based on H 2 yield. TGA and TPO analysis confirmed the presence of amorphous coke.

Core–shell nickel/nickel oxide combined with ruthenium bipyridyl photoredox complex was found to be adept, reusable, and highly selective for the carboxylation of various aryl and olefinic compounds with carbon dioxide at ambient temperature under 20 W light-emitting diode light. The carboxylation of a range of aromatic hydrocarbons and olefins afforded excellent product yield under 1 atm pressure of carbon dioxide without adding any additive/cocatalyst. Importantly, in the case of styrenes, insertion of CO2 took place at the benzylic C–H, whereas in normal olefins it occurred at the terminal site selectively. Moreover, the developed photocatalyst was highly stable, which allowed it to be recycled successfully for subsequent runs with almost consistent efficiency.

A Ni/NiO catalyst is reported for converting a phenolic compound, such as guaiacol, and cashew nut shell liquid (CNSL) into different hydrocarbons. High guaiacol conversion (80%) and higher cyclohe...

Mesoporous Ni/NiO with highest reported surface area among unsupported Ni/NiO catalyst is reported. The catalyst was prepared by chemical reduction in the presence of an organosilane template to stabilize the Ni/NiO structure and to create mesopores. Ni nanoparticles were embedded in NiO nanosheets. The material showed high surface area (282 m 2 /g) with 10–20 nm average Ni crystallite size and 20% metal dispersion. The concentration of Ni° in leached mesoporous Ni/NiO is 30% from XPS analysis, while 66% from EXAFS analysis. The catalyst showed intrinsic acidity of 0.2 mmol/g and ferromagnetic nature. Hydrodeoxygenation and hydrogenation reactions were studied. Nearly complete hydrodeoxygenation of methyl oleate and jatropha oil (99%), with >90% C9-C18 hydrocarbons selectivity, has been achieved. Hydrodeoxygenation of methyl oleate followed pseudo-first-order kinetics, and the activation energy was calculated as 48 kJ/mol. Nearly complete phenol hydrogenation (99%), and 100% selectivity for cyclohexanol was obtained. The activity of mesoporous leached Ni/NiO was found to be higher than the supported Pd and Ni catalysts due to desirable structure, high metal dispersion, large surface area, and high porosity.

Choice of hard carbon may not be an ideal selection in rechargeable sodium-ion battery anode when the performance is looked at a higher rate and longer cycle life. Herein, we report vanadium tri-oxides (V2O3) with different morphology produced by one step reduction process at a fixed temperature as a power capable sodium-ion battery anode. The comparison study of these different morphologies of V2O3 electrodes shows the porous hollow nanotube V2O3 electrode display better electrochemical performance against sodium metal in terms of high specific capacity, higher rate capability with extraordinary cycling stability without incorporating any graphene or carbonaceous materials to it. This porous hollow nanotube exhibits the 2nd cycle reversible capacity of ca. 318 mAh g−1 at a charging rate of 100 mA g−1 and it can even sustain up to 5300 cycles with 90% capacity retention. The average Coulombic efficiency was maintained at 99.94% with a very high current rate of 2000 mA g−1. We further investigate the sodiation mechanism by cyclic voltammetry and XANES technique in details. The study reveals that with suitable morphology and appropriate cell design can bring this V2O3 material as a promising anode in future sodium-ion battery technology.

High energy electrons on interaction with residual gas molecules present in the vacuum chamber of electron storage rings produce gas bremsstrahlung radiation. Extensive studies have been carried out in past to evaluate dose rate from gas bremsstrahlung using various simulation techniques with air as target gas. From these studies, empirical relations were deduced to evaluate gas bremsstrahlung dose rate. However storage rings at ultra high vacuum level contains primarily hydrogen and hydrocarbon gases as residue. In this work, effect of residual gas composition in vacuum chamber on gas bremsstrahlung dose rate in electron storage rings of energy range 1–3 GeV has been studied using FLUKA Monte Carlo code. Simulation study was performed to investigate effects on energy distribution, angular distribution and absorbed dose rate of gas bremsstrahlung due to various composition of residual gas normally encountered in vacuum chambers of storage rings. The gas bremsstrahlung dose rate was found to depend on effective atomic number and molecular mass of the residual gas molecules. From the study, a new empirical formula for the estimation of gas bremsstrahlung dose rate is proposed.

The present paper describes the first successful synthesis of an inorganic nanocomposite by grafting of cobalt (II) phthalocyanine (CoPc) on the core-shell Ni/NiO (NNO) semiconductor for the photocatalytic reduction of CO2 to methanol under visible illumination using triethylamine as a sacrificial donor. The synthesised photocatalyst exhibited a remarkable enhancement in the yield of methanol as compared to the semiconductor Ni/NiO and CoPc for CO2 reduction under identical conditions. The maximum yield of methanol was found to be 3641.2 μmol/g with the conversion rate of 151.7 μmol g−1 h−1 which was much higher than that observed with CoPc and semiconductor alone under identical experimental conditions. Furthermore, the synthesised nanocomposite showed superior activity as compared to the previously reported organic semiconductor bound cobalt complex photocatalyst. The composite photocatalyst was found to be highly stable which showed consistent recyclability for four runs without any significant loss in activity.

Hydroprocessing of neutral lipids extracted from Nannochloropsis sp. algal biomass was studied over sulfided cobalt molybdenum phosphorus/aluminium oxide (CoMoP/Al2O3) catalyst in a batch reactor at 300–375 °C with H2 at 50–120 bar. A clear light yellowish green product was obtained, containing 6–26% gasoline, 35 50% kerosene, 8–40% diesel, with 10–80% alkanes, 1–10% cycloalkanes, and 5–35% aromatics, with a maximum of 10% char formation in the process. Power law kinetic model was validated with experimental results. A kinetic study shows a pseudo 1st order reaction with respect to the neutral algae lipids oil concentration, with the activation energy for algal oil conversion over CoMoP/Al2O3 catalyst was 14.96 kJ/mol. Activation energies for the formation of diesel (125 kJ/mol) and kerosene (146 kJ/mol) were higher than for the heavy hydrocarbons such as PAH (7 kJ/mol) and alkanes (64 kJ/mol) products.

The epitaxial NiO layers deposited with higher fluence values are found to be strained, and the strain increases with the fluence values. The X-ray diffraction (XRD) profile taken from the synchrotron beam shows the presence of relaxed grains of NiO in addition to the strained grains, where the fraction of relaxed grains gradually increases with the fluence values. The presence of Pendellosung fringes in the XRD profile for the layers deposited at lower fluence values confirms good interfacial and crystalline qualities. As the fluence value is increased, the Pendellosung fringes start merging indicating relatively poor interfacial and crystalline qualities. The NiO layers are of epitaxial nature and grown along [111] direction with two domain structures that are in-plane rotated by 60° with respect to each other. The analysis of local structures from extended X-ray absorption fine structure measurements also indicates that the NiO lattice is strained at higher fluence values. The Ni–O bond distance does not change with the fluence values; however, Ni–Ni bond distance increases with the fluence values in corroboration with XRD results. The surface topography shows island growth of NiO at lower fluence values giving larger roughness, and these islands start merging with an increase in the fluence values leading to relatively smoother layers.

In-operando measurements were carried out for the first time to identify different intermediates and primary products formed during the conversion of lipids for catalytic as well as non-catalytic thermal hydroprocessing. Hydroprocessing of lipids was carried at 280–300 °C temperature, 40–60 bar pressure, 1500 Nl/L H2/Feed ratio and 1 h−1 space velocity in a fixed-bed tubular reactor. A high pressure metallic probe was used for collecting the FTIR spectra under these conditions. Under these conditions although the conversion of triglyceride molecules were complete, the deoxygenation reactions were less than 1%, with 6–7% carbon loss and 17–18% hydrogen loss into the gaseous phase corresponding to propane. In-operando FT-IR studies confirmed that depropanation (propane removal) is the primary reaction during catalytic hydroprocessing of triglycerides, along with formation of intermediates. For thermal hydroprocessing wide range of intermediates – alcohols, alkenes, ketones, anhydrides, ethers, acids, aldehyde and esters – were observed. Such intermediates indicate several undesirable coupling reactions such as C C bond formation, esterification, etherification and ketonization. For catalytic hydroprocessing only selective product intermediates were observed. Triglycerides hydroprocessing over Pd/Al2O3 catalyst predominantly produced carboxylic acid and aldehyde intermediates, along with very weak bands due to aromatics. Pd/C predominantly produced aldehydes with weak bands due to ketones. Sulfided CoMoP/Al2O3 catalyst also produced aldehydes predominantly, but also small quantities of carboxylic acids as intermediates, from trigycerides. IR bands due to alcohols, ethers, aromatics and cyclic ketones were observed at the later stage of reaction over CoMoP(S)/Al2O3 catalyst.

In the present contribution, structural and magnetic properties of Pulsed laser deposited (PLD) Co2FeGa (CFG) thin films have been studied as a function of substrate temperature. Structural investigation carried out by X-Ray Diffraction (XRD) measurement reveals mixed phase cubic structure of the films which changes from a nearly ordered to highly disordered phase with an increase in substrate temperature. Grazing Incidence X-Ray Diffraction (GIXRD) study shows the presence of disordered A2 phase similar to the bulk target. Grazing Incidence X-Ray Reflectivity (GIXR) measurement reveals the formation of bi-layer structure in the films with different density and thickness though the overall thickness remains same. Field Emission Scanning Electron Microscopy (FESEM) study shows the formation of a droplet-like morphology of the films. Extended X-ray Absorption Fine Structure (EXAFS) study serves a major role in complementing the XRD results and also shows a strong hybridization of Co with Ga maintaining the half metallicity. A novel approach in analyzing the EXAFS data additionally gives quantitative estimation of the different kinds of disorders present in the samples at the atomic level. In addition to this, magnetization result suggests that the films grown at lower substrate temperatures acts as proper ferromagnet following the well known spin wave theory with higher value of spontaneous magnetization in comparison to other samples. A lesser value of saturation magnetization in the films compared to bulk also supports the presence of antisite disorders.

The effect of temperature, pressure and H2/feed ratio was studied for hydroprocessing of light cycle oil (LCO) over sulfided NiMo supported on mesoporous H-ZSM-5. Mesoporous H-ZSM-5 catalyst used in this study was synthesized by hydrothermal method and ion exchange. The catalyst was characterized by N2 sorption studies, X-ray diffraction, scanning electron microscopy, transmission electron microscopy techniques. Polyaromatic hydrocarbons were reduced from 64 to 10 wt% at 300 °C and 60 bar. Mono-aromatics yield was increased to 60 wt% at higher temperature (380 °C). Properties like viscosity, cetane index, distillation (95% vol. recovery) and density of hydroprocessed LCO products at 380 °C, make it suitable for addition to diesel pool. At severe reaction conditions (380 °C and 70 bar), °API and cetane index values increased, while viscosity and density decreased. After 65 h of continuous run, polyaromatic hydrocarbons yield were increasing due to the loss of catalytic activity.

Mesoporous Ni/NiO catalyst was synthesized using an organosilane as a mesopore template. This is a simple and low-cost green method to synthesize mesoporous Ni/NiO catalyst for hydrogenation of glucose to sorbitol. The synthesized catalyst was characterized by N2 sorption, XRD, SEM, TEM, SQUID, and XPS techniques. The hydrogenation reactions were performed over the synthesized Ni/NiO catalyst in the temperature range of 100–150 °C and 50 bar pressure. The conversion of glucose was 95%, and sorbitol yield was 84 wt% best obtained at 130 °C. The turn over frequency calculated for glucose conversion over Ni/NiO is 0.20 s−1 at 130 °C. The kinetic study shows that glucose hydrogenation follows pseudo-first-order kinetic concerning glucose concentration. The activation energy calculated over the synthesized Ni/NiO catalyst was 16 kJ mol−1, 4 times lower than that over Raney nickel catalyst.

Hydroprocessing of light cycle oil was carried out in a fixed bed reactor. Sulfided hydroprocessing catalyst, Ni-Mo/SiO2-Al2O3 was used, and poly-aromatic hydrocarbons in the obtained products were reduced to 5 wt%, from 64 wt% in the feed, at 380 °C and 60 bar. The GC–MS analysis confirmed that 3-ring poly-aromatic compounds converted to alkyl substituted tetralin compounds. Aromatics yield increased by nearly 4–6 times (50 wt%) in the hydroprocessed products, which could be suitable for gasoline pool due to improved octane number. Mono-aromatic hydrocarbons concentration obtained was 35–55% at all the operating conditions in the hydroprocessed products. Higher concentration of mono-aromatics leads to the improved octane number of the fuel. Properties like viscosity, cetane index, °API, and density of hydroprocessed LCO products, lead us to conclude that the obtained products are suitable for diesel as well. Under severe reaction conditions (380 °C, 70 bar), °API and cetane index values increased whereas viscosity and the density value of the products decreased. The results indicate that the catalyst shows very stable performance with time regarding meeting the required specifications for diesel.