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This study shows the effect of vanadium doping on sodium titatane as an anode material for sodium ion battery application.

Herein, we report a facile synthesis of cauliflower-shaped ZnO structures through a hydrothermal method for efficient gas sensing applications. The ZnO structures were characterized by field emission scanning electron microscopy associated with energy dispersive spectroscopy (EDS), X-ray diffraction and Raman spectroscopy. XRD analysis revealed hexagonal wurtzite phase of ZnO crystals with excellent crystallinity and mean particle size of 45.50 nm. FESEM analysis showed cauliflower-like morphology composed of a large number of hexagonal nanorods. Cauliflower-shaped ZnO structures were used to device resistive sensor devices for NO2, NH3 and H2S gases. Gas responses for NH3 and H2S gases were not impressive even at high operating temperatures ranging from 200–450 °C. In contrast, for NO2 gas the responses were efficiently high even at very low operating temperatures. A maximum gas response of 431.36 was observed at very low operating temperature of 50 °C.

Introduction Most surgeons prefer a single implant for segmental proximal and diaphyseal femur fractures, although results are controversial and still no consensus for proper management is present. This prospective study analyses the functional and radiological outcome of managing 17 patients with ipsilateral shaft and proximal femur fractures by dual implant osteosynthesis at our center. Methods Over a two-year period, we managed 17 patients with a mean age of 35 years, with cancellous cannulated screws or dynamic hip screws for intracapsular femur fractures and improvised proximal femoral nail for extracapsular proximal femur fractures. Distal femoral locking plates or distal femoral nails were used for shaft femur fractures depending upon fracture morphology. The patients had a maximum follow-up of 18 months. Results A total of 80% of patients had a good functional outcome (using the Friedman-Wyman scoring system) while 60% had an excellent Harris Hip Score. The mean time taken for the bone union for proximal femur fractures was 4.75 months and for shaft femur fractures, it was 6 months. Conclusion We had a satisfactory functional and clinical outcome of managing these fractures with two implants, one focusing biomechanically on each fracture. This principle of dual implant osteosynthesis can reliably be used in such difficult fracture patterns and it negates the use of the single cephalomedullary nail for fixating both fractures.

This work demonstrates a facile synthesis of porous coral reef−like Mn3O4 (PC–Mn3O4) nanostructures via the hydrothermal process and their utilization as electrode materials in lithium ion battery (LIB). The structural and morphological investigations confirmed the coral reef−like morphology of obtained PC-Mn3O4. The obtained coral reef−like nanostructure owned the good specific surface area and high pore volume of ~118 m2 g−1 and ~0.277 cm3 g−1, respectively. For lithium ion battery application, the unique coral reef−like morphology of obtained PC-Mn3O4 exhibited the remarkable electrochemical performances with healthy lithium storage capacity, and excellent cyclability (such as 805.2 mAh/g at 0.1 C for 200 cycles; 246.5 mAh/g at 2.0 C after 450 cycles). It is believed that the obtained unique structure and its flexibility could be benefited to the effective structure enlargement, large generation of reaction sites and shorten the diffusion path for Li+ ions which considerably resulted in improving the electrochemical performance.

Two-dimensional porous nanodisks of NiCo2O4 have been synthesized by low temperature hydrothermal method followed by calcination at 500 °C/3 h/air. X-ray diffraction pattern confirmed the phase purity of the sample. Microstructure analysis clearly exhibits a unique porous nanodisks shape of NiCo2O4 sample. Brunauer–Emmett–Teller technique is also used to investigate the surface area and pore size of the sample. Electrochemical properties are evaluated via cyclic voltammetry and Galvanostatic cycling studies. NiCo2O4 as an anode exhibits excellent lithium storage capacity (673.9 mAh g−1 at 0.5C after 350 cycles; 596.9 mAh g−1 at 3.0 C after 200 cycles), high initial Coulombic efficiency (75%), long cycling stability (∼80% capacity retention at 350 cycles) and better rate capability (552.5 mAh g−1at 4.0 C), which is much higher than the theoretical capacity of graphite (372 mAh g−1). This improvement can be attributed to the unique porous structure of the electrode, which allows maximum Li+ ion to react with electrode material, shortens the diffusion path length and increasing the electrode/electrolyte contact area.

In this work, a pre-designed NiMnO3/Mn2O3 nanocomposite is synthesized via a facile urea-assisted auto-combustion synthesis method followed by annealing at 600 °C for 5 h in air as an anode material for lithium-ion batteries. Powder X-ray diffraction analysis confirmed the formation of the NiMnO3/Mn2O3 nanocomposite. Using Rietveld refinement analysis, the phase fraction of NiMnO3 and Mn2O3 phases was found to be ∼89% and ∼11%, respectively. It is believed that the interaction between NiMnO3 and Mn2O3 nanoparticles enhanced the charge transfer efficiency, which is favorable for an excellent electrochemical performance of the nanocomposite electrode. Electrochemical properties are evaluated via cyclic voltammetry and galvanostatic cycling studies. Benefiting from the high structural integrity and synergistic effect between NiMnO3 and Mn2O3, this nanocomposite exhibits a high reversible capacity (854.4 mA h g−1 at 1.0C for 200 cycles and 444.1 mA h g−1 at 2.0C for 500 cycles), excellent cycling stability (98% capacity retention after 200 cycles) and good rate capability (811.2 mA h g−1 at 2.0C). The values are much higher than the theoretical capacity of graphite (372 mA h g−1).

In this article, oval-shaped V2O5 nanoparticles were hydrothermally synthesized using a metal-organic framework (MOF), which was then followed by calcination under an air atmosphere. The obtained sample was characterized through various characterization techniques to determine the sample purity and the structural and morphological details. Since V2O5 possesses a layered crystal structure, it exhibits promising electrochemical performances as a cathode material for lithium-ion battery applications. However, poor cycling and inferior rate capabilities are the major issues that limit its application. Thus, a strategy to fabricate unique oval-shaped V2O5 nanoparticles was employed here to improve electrochemical performances using an MOF, which acts as a template and provides a skeleton for the growth of a novel nanostructure. It is believed that the oval-shaped morphology is beneficial to achieving better electrochemical results due to the large surface area and the existence of numerous channels for lithiation and de-lithiation. The obtained electrochemical result reveals that the V2O5 electrode can be considered a prominent cathode material for next-generation lithium-ion battery applications.

Pyro synthesis is a method to coat nanoparticles by uniform layer of carbon without using any conventional carbon source. The resultant carbon coating can be evaporated in the form of CO or CO2 at high temperature with the creation of large number of nanopores on the sample surface. Hence, a porous MnCo2O4 is successfully synthesized here with the same above strategy. It is believed that the electrolyte can easily permeate through these nanopores into the bulk of the sample and allow rapid access of Li+ ions during charge/discharge cycling. In order to compare the superiority of the porous sample synthesized by pyro synthesis method, MnCo2O4 nanoparticles are also synthesized by sol-gel synthesis method at the same parameters. When tested as anode materials for lithium ion battery application, porous MnCo2O4 electrode shows high capacity with long lifespan at all the investigated current rates in comparison to MnCo2O4 nanoparticles electrode.

Carbon-wrapped CuO is synthesized by a facile pyro-synthesis method without using a conventional carbon source to overcome the capacity fading issue of CuO nanoparticles. The microstructure analysis shows that the sample is fully wrapped by a carbon layer. The resultant carbon-wrapped CuO nanocomposite as an anode exhibits high reversible capacity with excellent cycling stability (437.1 mAh/g at 0.25 C and 365.2 mAh/g at 1.0 C after 100 cycles) and good rate capability. It is believed that the synergistic effect of CuO and carbon is responsible for the enhanced electrochemical performance of the nanocomposite electrode.

A facile polyol-assisted pyro-synthesis method was used to synthesize Co3O4 nanoparticles embedded into carbon matrix without using any conventional carbon source. The surface analysis by scanning electron microscopy showed that the Co3O4 nanoparticles (~20 ± 5 nm) are tightly enwrapped within the carbon matrix. CHN analysis determined the carbon content was only 0.11% in the final annealed sample. The Co3O4@carbon exhibited high capacities and excellent cycling performance as an anode at various current rates (such as 914.4 and 515.5 mAh g−1 at 0.25 and 1.0 C, respectively, after 50 cycles; 318.2 mAh g−1 at a high current rate of 5.0 C after 25 cycles). This superior electrochemical performance of the electrode can be attributed to the various aspects, such as, (1) the existence of carbon matrix, which acts as a flexible buffer to accommodate the volume changes during Li+ ion insertion/deinsertion and facilitates the fast Li+ and electron transfer and (2) the anchoring of Co3O4 nanoparticles within the carbon matrix prevents particles agglomeration.

A novel disk-like shape of Co3O4 with high porosity was synthesized by a facile hydrothermal approach followed by calcination at 485 °C for 2 h. In order to further confirm the crystal structure, morphology, particle size, surface area, and porosity of the sample, a series of corresponding characterization techniques were used. The disk-like shape of Co3O4 as an anode delivered excellent rate capability such as 510.5 mAh g−1 at 4.0 C, which is much higher than the theoretical capacity of commercial graphite anode (372 mAh g−1). However, the electrode could not recover the high capacity during the long-term cycling at various higher current rates due to the deformation of the structure as confirmed by the ex situ studies. It is believed that the obtained remarkable structural feature with numerous void pores within the structure may be helpful for short-term cycling due to the large contact areas between the electrode and the electrolyte and a shorter diffusion length for lithium ion insertion but unable to act as a buffer to relax the volume expansion/contraction and alleviate the structural damage of the electrode during long-term cycling.

An optimized amount of cetyltrimethylammonium bromide (CTAB) as a surfactant was used for the first time to fabricate porous TiO2 nanofibers by an electrospinning technique combined with post-annealing at 500 °C for 5 h in air medium. The fabricated porous TiO2 nanofibers were systematically characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, surface area measurements and electrochemical testing. The porous TiO2 nanofibers contained numerous surface pores with an average diameter of ∼80–90 nm. As an anode, the porous TiO2 nanofiber electrode delivered not only a high reversible capacity and excellent cycle stability over 100 cycles but also excellent rate capability at various current rates in comparison to control TiO2 nanofibers (prepared in the absence of CTAB). The rapid transportation of lithium ions and reduced lithium ion diffusion length probably are responsible for the improved electrochemical performances of the porous TiO2 nanofiber electrode synthesized in the presence of the CTAB surfactant.

Background: Treatment of tuberculosis of spine has various modalities ranging from medical to various surgical forms including just drainage of pus to only decompression and decompression with instrumentation. The goals of surgery include radical debridement of the infective focus. In some cases, when surgery causes mechanical spinal instability, the question arises whether the risk of recurrent infection outweighs the benefits of spinal instrumentation and stabilization. Instrumentation helps in preventing progression of kyphosis and helps in maintaining the achieved correction. Materials and Methods: Forty-three cases of both sexes with spinal tuberculosis treated with anterior decompression with instrumentation were reviewed retrospectively. Patients with medically managed disease and those who did not receive instrumentation were eliminated from this review. The mean age of patients was 42.3 years (20–72). The mean follow-up duration was 31.6 months (72 to 12 months). Results: Result was analyzed clinically and radiologically in the form of neurological improvement, correction of kyphosis, and maintenance of correction. All patients with wet lesion showed neurological improvement and showed no or very minimal progression of kyphosis. The mean preoperative kyphosis was 27.2° (50 to 16). The mean postoperative kyphosis was 9.0° (20 to 0) and the mean kyphosis at follow-up was 10.3°. None of the patients showed hardware failure, deep infection, and wound infection, and no patient required hardware revision. Conclusion: Instrumentation of the spine is safe and has an important role in stabilization of the tuberculosis of the spine. Despite the presence of active infection, instrumentation after radical debridement will not increase the risk of recurrent infection. In fact, greater benefit can be achieved through spinal stabilization, which can even promote accelerated healing and avoids progression of kyphosis. Level of Evidence: 2

Fe2O3 nano-particles and nano-rods were synthesized by hydrothermal synthesis method under different reaction conditions and then applied as anode materials for Lithium ion batteries. Microstructural analysis confirmed these two shapes and structures for Fe2O3 samples. It was noticed that the electrochemical performance of Fe2O3 is highly influenced by its particle morphology. Unexpectedly, Fe2O3 nano-particles exhibit excellent electrochemical performances as compared to nano-rods morphology, which may be due to the least micro strain, high stability of nano-particles structure, small agglomerations, etc. It is believed that the nano-particles structure provides extra reaction sites to accommodate large Li-ions, shorten the Li-ion diffusion paths to improve the electronic conductivity and offers large electrolyte/electrode contact area for fast electrochemical reactions. In contrast, the nano-rods morphology could not hold its structural integrity during the lithiation/de-lithiation reactions and collapsed only after certain number of cycles giving rise to poor electrochemical performances, as confirmed by post cycling ex-situ studies. More precisely, Fe2O3 nano-particles electrode delivered the excellent reversible capacity of 1125 mAh g−1 and 1007 mAh g−1 at 1C and 4C after 100 and 80 cycles, respectively, while Fe2O3 nano-rods exhibit only 113.5 mAh g−1 at 1C and 326.7 mAh g−1 at 4C.

In the present work, one–dimensional porous NiO nano-rods as an anode material were synthesized using facile hydrothermal synthesis method to improve the electrochemical performance for LIBs application. The NiO nano-rods were typically several hundred nanometers in length, which are composed by loosely stacked nanoparticles. It is believed that the obtained architecture with mesoporous structure can ensure rapid electrons/ions transfer, penetration of the electrolyte to the electrode surfaces and buffer the volume expansion of NiO during charge/discharge processes. When evaluated as anode material, the NiO nano-rods exhibit excellent rate performance and long-life cycling performance with high reversibility. The porous NiO nano-rods exhibit a capacity of 1029.3 mA h g−1 at 1C up to 100 cycles and even retains a reversible capacity of 548.4 mA h g−1 at 4C after 80 cycles. Thus, it is believed that the current strategy can be applicable to improve the electrochemical performances of various metal oxide electrodes in rechargeable secondary battery.

NiFe2O4 nanoparticles fully anchored within a carbon network were prepared via a facile pyro-synthesis method without using any conventional carbon sources. The surface morphology was investigated using field-emission scanning electron microscopy, which confirmed the full anchoring of NiFe2O4 nanoparticles within a carbon network. The primary particle size of NiFe2O4 is in the range of 50–100 nm. The influence of the carbon network on the electrochemical performance of the NiFe2O4/C nanocomposite was investigated. The electrochemical results showed that the NiFe2O4/C anode delivered a reversible capacity of 381.8 mA h g−1 after 100 cycles at a constant current rate of 1.0C, and when the current rate is increased to a high current rate of 5.0C, a reversible capacity of 263.7 mA h g−1 is retained. The obtained charge capacity at high current rates is better than the reported values for NiFe2O4 nanoparticles. The enhanced electrochemical performance can be mainly ascribed to the high electrical conductivity of the electrode, the short diffusion path for Li+ ion transportation in the active material and synergistic effects between the NiFe2O4 nanoparticles and carbon network, which buffers the volume changes and prevents aggregation of NiFe2O4 nanoparticles during cycling.

Customer Satisfaction has been a psychological attribute inviting attention of the customers and requiring decipher their contribution in overall business performance.Banking has been no exception to this phenomenon.Many Literatures have found a strong relationship between service quality and customer satisfaction In service sector in general and banking industry in particular. The aim of the study is to investigate the relationship between service quality and customer satisfaction. The study assesses the level of customers’ satisfaction and service quality performance of the select banks. Further the study compares the satisfaction and service quality in select public and private sector banks.The study also identifies the area where the banks need to focus. The research design is descriptive as the research is intended to conclude and suggest measures to zero down on the service quality gaps in select public and private sector banks. The result shows a positive relationship between service quality and customer satisfaction. Service quality dimensions (tangibility, reliability, responsiveness, assurance and empathy) show wide service quality gaps. The comparative study of public sector banks and private sector banks show superiority of private sector banks over public sector banks in customer satisfaction and performance of service delivery.

In this work, the nanorod structured Na2Ti6O13/Na2Ti3O7 nanocomposite anode is synthesized via facile solvothermal method for sodium ion battery application. The Lebail refinement analysis was performed to obtain the phase fractions ratio of Na2Ti6O13 and Na2Ti3O7 in the nanocomposite sample. It was found to be ~82% and ~ 18% for Na2Ti6O13 and Na2Ti3O7 phases, respectively. The microstructure analysis confirmed the nanorods morphology of the nanocomposite sample, which are self-assembled in hierarchal manner and exhibits the flower-like morphology at high magnifications. The obtained morphology demonstrates remarkable electrochemical performances such as superior cycling stability of 182 mAh g−1 at 100 mA g−1 after 165 cycles and high rate capability of 161 mAh g−1 at 500 mA g−1 over 100 cycles, which can be ascribed to the excellent synergetic effect between Na2Ti6O13 and Na2Ti3O7 phases that could effectively nullify the drawbacks of individual phases and thereby act as complementary to each other advantages.

A unique strategy has been designed to synthesize CuCo2O4/CuO nano-composite by using facile pyro-synthesis method. A pyro-synthesis is a well‒known method to carbon coat the nanomaterials without using any carbon source. The network of carbon formed during pyro-synthesis was eventually evaporated by calcination in air, which simultaneously led to the partial reduction of CuCo2O4 to CuO due to the consumption of carbon under reduced atmosphere. Formation of CuCo2O4/CuO nano-composite was confirmed through powder X-ray diffraction analysis. Phase fractions of CuCo2O4 and CuO in the nano-composite obtained after the Rietveld refinement was ~71.1 and 28.9 wt%, respectively. Employing this nano-composite as an anode exhibit excellent cycling stability (675.8 mAh g−1 at 0.1 C and 300.3 mAh g−1 at 1.0 C after 60 and 100 cycles, respectively) and better rate capability (122.4 mAh g−1 at 3.0 C), which can be ascribed to the unique architecture of the electrode with high structural integrity and excellent synergy between CuO and CuCo2O4 nanoparticles.

Growth has both financial and social dimensions and is partial without the improvement of women who constitute about fifty percent of the general populace. It miles a general notion that women as a mother, wife, daughter, daughter-in-law and as many more characters in their life have to bear numerous responsibilities of their families. Women have broken four walls around them build by their family members and society and enter into a new world where they have their own identity. Now women have started taking part in the construction of the new world, having more potential, possibilities and opportunities. Strengthening women entrepreneurs is an essence of achieving the non-stop and sustainable economic improvement of the country. By the time, the world comprehended that growth of any economy cannot reach its par without the energetic participation of the women in shaping the state. Women entrepreneurs face social, financial, organizational, mental and diverse other issues whilst running their venture. Aside from all the restrains, Indian women move onward and are cherished for their achievements of their respective area. The objective of this paper is to become aware of the problems and difficulties that women face in the direction of their entrepreneurship.

A facile and straightforward method was adopted to synthesize ZnCo 2 O 4 /graphene nanocomposite anode. In the first step, pure ZnCo 2 O 4 nanoparticles were synthesized using urea-assisted auto-combustion synthesis followed by annealing at a low temperature of 400 °C. In the second step, in order to synthesize ZnCo 2 O 4 /graphene nanocomposite, the obtained pure ZnCo 2 O 4 nanoparticles were milled with 10 wt% reduced graphene nanosheets using high energy spex mill for 30 s. The ZnCo 2 O 4 nanoparticles, with particle sizes of 25–50 nm, were uniformly dispersed and anchored on the reduced graphene nanosheets. Compared with pure ZnCo 2 O 4 nanoparticles anode, significant improvements in the electrochemical performance of the nanocomposite anode were obtained. The resulting nanocomposite delivered a reversible capacity of 1124.8 mAh g −1 at 0.1 C after 90 cycles with 98% Coulombic efficiency and high rate capability of 515.9 mAh g −1 at 4.5 C, thus exhibiting one of the best lithium storage properties among the reported ZnCo 2 O 4 anodes. The significant enhancement of the electrochemical performance of the nanocomposite anode could be credited to the strong synergy between ZnCo 2 O 4 and graphene nanosheets, which maintain excellent electronic contact and accommodate the large volume changes during the lithiation/delithiation process.

A comparative electrochemical study of undoped NiO and Co-doped NiO is performed in order to elucidate the effect of the Co distribution in the crystal lattice of NiO for energy storage applications. Both samples are synthesized using a facile solvothermal strategy and characterized systematically by X-ray diffraction, field-emission scanning electron microscopy, field-emission transmission electron microscopy, X-ray photoelectron spectroscopy and charge/discharge measurements. It is found that doping process does not affect the phase structure of pristine NiO. However, it obviously significantly influences the morphology, suppresses the particles agglomeration and enhances the specific surface area of NiO. More importantly, the substitution of Co for Ni site enhances the p-type conductivity of NiO via the generation of holes. Consequently, the obtained Co-doped NiO anode displays superior Li-battery performance with a large reversible capacity, excellent cyclic performance, and good rate capability in comparison to undoped NiO.

ZnMn2O4/C nanoparticles are synthesized by one step polyol assisted pyro-synthesis for use as the anode in rechargeable lithium ion batteries without any post heat treatment. The as-prepared ZnMn2O4/C is tetragonal with a spherical particle size in the range of 10–30 nm. Electrochemical measurements were performed using the as-prepared powders as the active material for a lithium-ion cell. The nanoparticle electrode delivered an initial charge capacity of 666.1 mAh g−1 and exhibited a capacity retention of ∼81% (539.4 mAh g−1) after 50 cycles. The capacity enhancement in the as-prepared ZnMn2O4/C may be explained on the basis of the polyol medium that enables to develop a sufficient carbon network that can act as electrical conduits during electrochemical reactions. The carbon network appears to enhance the particle-connectivity and hence improve the electronic conductivities.

In this work, pure LVP nanoparticles and an LVP/graphene nanocomposite are successfully synthesized by a simple and cost effective polyol based solvothermal method, which can be easily scaled up. The synthesized nanocomposite contained small (30–60 nm) LVP nanoparticles completely and uniformly anchored on reduced graphene nanosheets. As a cathode for lithium ion batteries, the nanocomposite electrode delivered high reversible lithium storage capacity (189.8 mA h g −1 at 0.1 C), superior cycling stability (111.8 mA h g −1 at 0.1 C, 112.6 mA h g −1 at 5 C, and 103.4 mA h g −1 at 10 C after 80 cycles) and better C-rate capability (90.8 mA h g −1 at 10 C), whereas the pure LVP nanoparticles electrode delivered much less capacity at all investigated current rates. The enhanced electrochemical performance of the nanocomposite electrode can be attributed to the synergistic interaction between the uniformly dispersed LVP nanoparticles and the graphene nanosheets, which offers a large number of accessible active sites for the fast diffusion of Li ions, low internal resistance, high conductivity and more importantly, accommodates the large volume expansion/contraction during cycling.

ZnCo 2 O 4 /graphene and pure ZnCo 2 O 4 nanoparticles were synthesized by simple and low temperature urea-assisted auto-combustion method and annealed at 400 °C for 5 h in air atmosphere. The electron microscopy image of the obtained ZnCo 2 O 4 /graphene nanocomposite revealed that the ZnCo 2 O 4 nanoparticles were randomly distributed and anchored on the surface of reduced graphene nanosheets. The graphene nanosheets significantly reduced the particles size and suppressed the aggregation of ZnCo 2 O 4 nanoparticles as well as maintaining the good electrical conductivity of the overall sample. The size of the nanoparticles was in the range of 50–100 nm and the size of nanoparticles in the nanocomposite sample in the range of 25–50 nm. The electrochemical results showed that the ZnCo 2 O 4 /graphene nanocomposite electrode had greatly improved cycling stability with high reversible capacity of 755.6 mAh g −1 after 70 cycles, and better rate capability of 378.1 mAh g −1 at 4.5 C than pure ZnCo 2 O 4 nanoparticles (299.8 mAh g −1 after 70 cycles and 302.4 mAh g −1 at 4.5 C). The enhanced electrochemical performance of the nanocomposite could be ascribed to the positive synergistic effect of the combination of the ZnCo 2 O 4 nanoparticles and conducting graphene nanosheets.

A B S T R A C T A facile urea-assisted template-free, surfactant-less chemical co-precipitation method was used to obtain a flower-like cobalt oxide sample followed by annealing at various temperatures of 400, 500, and 600 � C for 2 h. The obtained flower-like morphology was assembled by nanorods, and the nanorods were comprised of interconnected particles with a porous structure. The changes in the surface area of the obtained flower-like Co3O4 samples were systematically examined at various temperatures and their impact on the electrochemical performances was observed. Electrochemical investigation showed that the flower-like Co3O4 samples obtained at 500

A cobalt-poor or iron rich bicomponent mixture of Co0.9Fe2.1O4/Fe2O3 and Co0.8Fe2.2O4/Fe2O3 anode materials have been successfully prepared using simple, cost-effective, and scalable urea-assisted auto-combustion synthesis. The threshold limit of lower cobalt stoichiometry in CoFe2O4 that leads to impressive electrochemical performance was identified. The electrochemical performance shows that the Co0.9Fe2.1O4/Fe2O3 electrode exhibits high capacity and rate capability in comparison to a Co0.8Fe2.2O4/Fe2O3 electrode, and the obtained data is comparable with that reported for cobalt-rich CoFe2O4. The better rate performance of the Co0.9Fe2.1O4/Fe2O3 electrode is ascribed to its unique stoichiometry, which intimately prefers the combination of Fe2O3 with Co1−xFe2+xO4 and the high electrical conductivity. Further, the high reversible capacity in Co0.9Fe2.1O4/Fe2O3 and Co0.8Fe2.2O4/Fe2O3 electrodes is most likely attributed to the synergistic electrochemical activity of both the nanostructured materials (Co1−xFe2+xO4 and Fe2O3), reaching beyond the well-established mechanisms of charge storage in these two phases.

We present a facile and cost-effective urea-assisted auto-combustion method for synthesizing pure MgFe{sub 2}O{sub 4} nanoparticle and MgFe{sub 2}O{sub 4}/graphene nanocomposite samples followed by annealing at 600 °C for 5 h under N{sub 2} atmosphere. The X-ray diffraction pattern confirmed the single phase formation for both samples. The obtained morphology of the nanocomposite sample shows that the MgFe{sub 2}O{sub 4} nanoparticles are highly dispersed on conductive graphene nanosheets with particle size in the range of 50–100 nm. When applied as an anode material, MgFe{sub 2}O{sub 4}/graphene nanocomposite electrode shows a high reversible charge capacity of 764.4 mAh g{sup −1} at 0.04 C over 60 charge/discharge cycles and in spite of that it also retained a capacity of 219.9 mAh g{sup −1} at high current rate of 4.2 C. The obtained result is much better than the synthesized pure MgFe{sub 2}O{sub 4} nanoparticle electrode. The excellent electrochemical performance of the MgFe{sub 2}O{sub 4}/graphene nanocomposite electrode can be attributed to the strong favorable synergistic interaction between MgFe{sub 2}O{sub 4} and reduced graphene nanosheets, which supplied a large number of accessible active sites for Li{sup +}-ion insertion and short diffusion length for both Li{sup +} ions and electrons. In addition, the graphene nanosheetsmore » in the nanocomposite electrode provide high conductivity and accommodate the large volume expansion/contraction during cycling, resulting in high capacity and long cycling stability. - Highlights: • MgFe{sub 2}O{sub 4}/graphene nanocomposite was synthesized by facile urea-assisted method. • Such well-designed structure results in fine and strong interfacial interaction. • Nanocomposite anode shows high rate capability and long cycling stability. • Better performance is due to synergistic effect between MgFe{sub 2}O{sub 4} and graphene. • Simple, low cost and fast synthesis is attractive for large scale applications.« less

The effects of molybdenum (Mo 6+ ) doping on the electrochemical properties of anatase-type titanium dioxide (TiO 2 ) were investigated. The Mo 6+ -doped TiO 2 samples were prepared using a simple and cost-effective solvothermal method with the doping levels of 1, 3, and 5 wt%, followed by annealing at a low temperature of 300 °C for 5 h. High-resolution synchrotron X-ray diffraction and electron microscopy were conducted to know the structural and morphological properties of doped TiO 2 samples. The dopant significantly suppresses the growth of TiO 2 grains and reduces the particles sizes, which can also improve markedly the performance and stability of charge/discharge cycles. The particles sizes are in the range of 115–250 nm and 5–10 nm for undoped and Mo-doped TiO 2 nanoparticle samples, respectively. Electrochemical results show that the Mo 6+ -doped TiO 2 nanoparticle samples display a significantly lower charge transfer resistance, higher rate capability and excellent reversibility. Author’s believed that the high rate performance offered by Mo-doped TiO 2 nanoparticle electrodes may be attributed to the enhanced electronic and ionic conductivity, which are achieved by increasing the number of Ti 4+ vacancies in the lattice via Mo 6+ doping, which may lead to the generation of more free holes in the doped p-type semiconductor. The increased hole concentration in the valence band can contribute to the electrical conductivity of the doped sample.

A simple and efficient approach was developed to synthesize CuO nanoparticles with improved electrochemical performance. Potassium (K+)-doped CuO nanoparticles were synthesized by a simple and cost-effective solvothermal method followed by annealing at 500 °C for 5 h under air atmosphere. For comparison, an undoped CuO sample was also synthesized under the same conditions. X-ray diffraction analysis demonstrates that the K+ ion doping caused no change in the phase structure, and highly crystalline KxCu1−xO1−δ (x = 0.10) powder without any impurity was obtained. As an anode material for a lithium ion battery, the K+-doped CuO nanoparticle electrode exhibited better capacity retention with a reversible capacity of over 354.6 mA h g−1 for up to 30 cycles at 0.1 C, as well as a high charge capacity of 162.3 mA h g−1 at a high current rate of 3.2 C, in comparison to an undoped CuO electrode (275.9 mA h g−1 at 0.1 C and 68.9 mA h g−1 at 3.2 C). The high rate capability and better cycleability of the doped electrode can be attributed to the influence of the K+ ion nanostructure on the increased electronic conductivity, diffusion efficiency, and kinetic properties of CuO during the lithiation and delithiation process.

A facile and cost-effective urea-assisted autocombustion strategy has been designed for the fabrication of Co3O4/CoFe2O4 nanocomposite and pure CoFe2O4 anode materials followed by annealing at 700 and 900 °C for 6 h, respectively. To confirm the exact structure, Rietiveld analysis was performed on the Synchrotron XRD pattern of both the CoFe2O4 samples annealed at 700 and 900 °C. The results clearly depicts the formation of two phases (Co3O4:CoFe2O4) with the ratio of [76.3(5):23.6(3)%] in the sample annealed at 700 °C sample, while single phase CoFe2O4 formation was observed for the sample annealed at 900 °C. It has also been found that the designed nanocomposite sample is composed of small nanoparticles (50–100 nm), while the size of pure CoFe2O4 particles is in the range from 600 nm to 1 μm. When applied as an anode material, the obtained Co3O4/CoFe2O4 nanocomposite electrode exhibits high reversible capacity as well as excellent cycling stability and better rate capability in comparison to a pure CoFe...

The present study attempts to explore structure of relationships among service quality, customer perceived value, customer satisfaction and behavioral intentions through a comprehensive survey of extant literature. The study investigates the direct and indirect relationship between service quality and behavioral intention and probes into the mediating role of customers' perceived value and customers' satisfaction in the indirect relationship between service quality and behavioral intention. The findings suggest that service quality and behavioral intention relationship is mediated at multiple levels as their relationship passes through the junctions of customer perceived value and customer satisfaction.

The effect of doping of Fe at Cu2+ and Ti4+ sites in calcium copper titanate, CaCu3Ti4O12, has been examined. The compositions CaCu3−xFexTi4O12 (CCFTO) and CaCu3Ti4-xFexO12 (CCTFO), (x = 0.10) have been synthesized by citrate nitrate gel route. XRD analysis confirms the formation of single- phase ceramics on sintering at 900 °C for 8 h. Structure of CaCu3Ti4O12 does not change on doping with iron on Cu-site or Ti-site and it remains cubic. Surface morphology indicates that the average grain size is in range of 30–90 μm and 5–7 μm for systems CCFTO and CCTFO, respectively. EDX studies confirm the presence of Ca2+, Cu2+, Ti4+ and Fe3+ ions as per stoichiometry of ceramics. The grain resistance of CCTFO is higher than that of CCFTO. Values of dielectric constant (e r ) and dielectric loss (tanδ) of CCTFO are higher than those of CCFTO ceramic at all measured frequencies and temperatures.

The relationship between service quality and customer loyalty is a vastly researched marketing phenomena which have been assessed and established across different industries. Service quality plays a prominent role in determining customers’ status of loyalty (Boulding et al., J Mark Res 30:7–27, 1993; Parasuraman et al., J Retail 67:420–450, 1991; Zeithaml et al., J Mark 60:31–46, 1996) as it is the primary factor that affects chances of customers’ revisit or repurchase from the company. Being a significant contributor in customer loyalty formation, service quality also gets influenced by certain other factors which exert moderate effects on its relationship with customer loyalty. The present study intends to expose the service quality–customer loyalty relationship in life insurance industry and offers further insights into the aforementioned relationship by assessing the moderating influences of trust, commitment, corporate image and switching costs, the variables that the literature established as important factors in determining customer loyalty. A research model encompassing the direct association of service quality with customer loyalty and the possible moderating variables whose presence affects this association is proposed and empirically tested on the basis of responses from life insurance customers.

In this work, almost pure Na x CoO 2 ( x =0.71) sample has been prepared via a solid-state route. The stoichiometric composition has been estimated by ICP-AES analysis and the Rietveld refinement performed on the respective XRD pattern led to an orthorhombic structure in the Cmcm space group with a =2.83218(3) A, b =4.89983(4) A, and c =10.92334(14) A. The insertion/deinsertion of sodium into the well-crystallized particles leads to capacities as high as 70.4 mAhg −1 with an initial Coulombic efficiency of 90%, and excellent capacity retention of almost ~100% after the 90th cycle between a 2.0 and 3.5 V voltage window for a 0.08 C–rate. The insertion ratio ( x ) varied between 0.592 and 0.673 during the deinsertion/insertion process within Na x CoO 2 . The voltage profile shows numerous voltage steps being mainly associated to the slight ordering of the Na ions within the layers. By coupling the electrochemical process with an in-situ X-ray diffraction experiment, the c-axis and a-axis peak positions such as (002), (004) and (100) are shifted with the accompanying deintercalation/intercalation of sodium, suggesting that the extracted sodium has been reversibly occupied with a small variation in sodium composition ranges due to peculiar Na + /vacancy ordering.