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With the high competition in market, the increase in quality and reliability of gas sensors is highly desirable. Compatible gas sensors having high precision, high sensitivity, economical have attracted a lot of attention. For good gas sensing, research on sensing material have been broadly focused. An improvement in Nano technology and use of different materials has led to the development of efficient and effective gas sensors. The Nano- materials manifest properties that are incomparable with the granular polycrystalline counterpart. With the advancement in Micro and Nano technology, micro-sized gas sensors have been developed with great sensing performance. For detection of toxic gases various techniques are available but solid state gas sensors offer a wide spectrum of materials and their sensitivities towards various types of gases. Of all the solid state gas sensing materials, semiconductor metal oxide nanostructures are more preferable due to the stability of their oxides, high response, low cost for fabrication, response to wide range of chemicals etc. They are cost effective, reliable, and robust and have quick response time. In this paper we have studied about the semiconductor metal oxide gas sensors. The effects due to morphological structure on sensing properties are also discussed. The existing detailed literature survey on techniques and mechanisms for the nanostructures and their gas sensing ability are also involved.

The need for replacing conventional sources of energy with renewable ones has been on a swift rise since the last couple of decades. In this context, the progress in third-generation solar cells has taken a good leap in the last couple of years with increasing prospects of high efficiency, stability, and lifetime. Quite recently, a new form of carbon has been discovered accidentally in the form of carbon quantum dots (C QD), which is being pursued actively owing to its chemical stability and luminescent properties. In the current work, we report highly luminescent C QD prepared

Despite the widespread use of several diagnostic tests in subacute thyroiditis (SAT), their usage remains largely subjective. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are useful indicators of inflammation in patients with SAT. The purpose of this study was to compare the scope for utilising CRP and ESR objectively in deciding the requirement of glucocorticoid therapy.A total of 28 patients with SAT were included in this study. Serum CRP and ESR were measured in all the patients. The characteristics of these tests were assessed firstly by using previously accepted positivity criterion for the particular diagnostic test. The area under the receiver operating characteristics (ROC) curve was obtained to provide an index of the overall discriminative ability of both tests.Fifteen out of 28 patients were found to have features of significant thyroid inflammation eventually requiring glucocorticoid based on the current recommendations. The mean CRP value was significantly higher in patients requiring glucocorticoids. The ROC curves indicated that the optimal positivity criterion was 19.3 mg/L for the CRP level and 46 mm at the 1The serum CRP level provided a clear advantage over ESR in the assessment of the severity of inflammation before initiation of glucocorticoid therapy in SAT. However, a well-powered study is needed to examine the clinical relevance of such a role for CRP in thyroidology.

Background: The modulation in electrical conductivity of polymer electrolyte, viz., polyethylene oxide (PEO) complexed with different concentrations of sodium iodide is studied. The role of mobility and charge concentration in the electrical conductivity of polymer electrolytes is established. Methods: The complex impedance spectroscopy (CIS) method is used to measure the electrical conductivity of film. Results: Conclusion: The polarized optical microscopy (POM) is used to study the morphology of the surface of PEO, PEO+NaI films dispersed with Si.

Often newer practical materials and devices, with huge economic gains, have resulted from commercialization of suitable selections of latest research on materials and their applications. Spread of laboratory discoveries of semiconductors and their properties to practical applications in every sphere of life and industry is the easiest example. Present work will focus on a few random examples of newer materials science research topics that is, or may possibly be, commercially exploited. Piezoelectric (PE) materials including High Temperature (HT) PE materials will be outlined for industry to explore novel applications ranging from ultrafine manipulation to heavy duty drilling and making PE sensors, actuators and ultrasonic devices. Higher electrical conductivity of a defect form of II=VI oxides (Cd-O in particular) is highlighted for possible practical exploitations. For 2nd generation Electromagnetic Interference (EMI) Shielding, polymeric composites with either newer absorbing agents or newer reflecting agents or their mixtures will be outlined. Novel Fe- or Ni- based HTSCs (high temperature superconductors) are less anisotropic and rather metallic in contrast to Cu-oxide HTSCs. So, these offer added advantage for making superconducting electrical cables. A balanced presentation of these potentially usable materials and their basic physics will be attempted.

The emergence of fluorescence quantum dots (QDs) has led to the development of variety of applications in science and technology. Owing to the diverse optical and electrical properties of CdS QDs we have synthesized the same using wet chemical method. The QDs have been prepared at sub-room temperature using a new solvent comprising a mixture of water and methanol. The QDs when seen under UV light radiate violet color. The band-gap of the QDs deduced from the absorption spectra was 3.08 eV while PL spectra of the QDs suggested possibility of multiple exciton generation with a close to narrow size distribution. XRD analysis confirmed cubic structure of the particles. The obtained results suggest that these QDs can play ideal role in quantum dot sensitized solar cells (QDSSC) or in light emitting diodes (LEDs).

Solar energy being a vital source of energy for the future generations, it is necessary to make solar cells cost effective. The quest for cost effective and environmental friendly energy source has led to the development of dye sensitized solar cell (DSSC). In the present work we have explored the extraction and optical and electrochemical properties of Syzygium Cumini or commonly known as Jamun. The dye has been successfully used over mesoporous titania (TiO2) as sensitizer in DSSC with polymer electrolyte. The efficiency improved when an additional layer of reduced graphene oxide was embedded prior to TiO2. Overall the photovoltaic parameters suggest that the dye characteristics could be improved to give better efficiency. Furthermore, compared to the cost of the standard Ruthenium N719 dye, the cost of Jamun dye is inexpensive making it a highly economical dye for DSSC.

Manganese oxide-Nickel oxide (MnO2-NiO) has been successfully deposited on Fluorine doped Tin Oxide (FTO) glass electrode using a facile, effective and low cost electrodeposition process and was used as counter electrode (CE) in dye-sensitized solar cells (DSSC). The cells were characterized using electrochemical impedance spectra and cyclic voltammetry, which revealed enhanced electrocatalytic ability for the reduction of triiodide/iodide (I3− to I−). Further, the photocurrent–voltage (J–V) characteristics under the illumination of 100 mW/cm2 were studied. The DSSC with MnO2-NiO CE revealed higher short-circuit current density (Jsc) of 0.3 mA/cm2, open-circuit voltage (Voc) of 0.83 V, and fill factor of 0.84. This suggests that the electrodeposited MnO2-NiO coated FTO electrode can be used to replace the commonly employed and expensive metal platinum (Pt) in DSSC.

This work shows a comparative study of two types of surface barrier diodes (SBDs). RF magnetron sputtering was used to fabricate Al doped ZnO films (Al0.02Zn0.98O) at two different temperatures (100 and 300 °C) and then the structural and optical properties of these thin films were obtained and analyzed using SEM, AFM, XRD, EDX and UV–Vis spectroscopy. Then the heterojunction layers Pd/Al-ZnO/p-Si (SBD1) & Au/Al-ZnO/p-Si (SBD2) were prepared using these Al-ZnO films (developed at both the temperatures). Optical and electrical properties and the effect of temperature on ideality factor, barrier potential and carrier concentration of both the SBDs were also studied.

In the last couple of years the use of carbon allotropes in energy generating and energy storage devices has increased owing to their exceptional properties. In applications where charge transfer is required, reduced graphene oxide (rGO) is the preferred choice. The current work reports the synthesis of rGO by microwave and electrochemical method. Further the rGO have been used in the working electrode of DSSC in various configurations. Using quasi-solid polymer electrolyte we obtained a short circuit current density (Jsc) of 2.15 mA/cm2, open circuit voltage (Voc) of 0.54 V and an efficiency (η) of 0.58%. Because of the presence of polymer electrolyte the cell parameters improved after a period of 72 h and the same have been presented with their electrochemical impedance studies.

Plenty of options for inorganic electron transport materials (ETMs) for perovskite solar cells (PSCs) are available. However, most hole transport materials (HTMs) is of organic nature. Organic materials are less stable as they are easily degraded by water and oxygen. Developing more variants of inorganic HTM is a major challenge. Till date, many materials have been reported, but their performance has not superseded that of their organic counterparts. In this review article, we look into the various inorganic HTMs that are available and analyze their performance. Apart from stability, their performance is also a concern for reproducible parameters of device performance. CuSCN, NiOx and MoS2 based PSCs are highly stable devices, maintaining power conversion efficiency (PCEs) over 20% whereas, number of devices made from CuI, CuOx, CuS, CuGaO2 and MoOx but shows low PCEs below 20%. Recently, HTM-free carbon/CNTs/rGO based PSCs shows promises for commercialization. Inorganic HTMs is overcoming the stability and cost issue over organic HTMs, various techniques, their novelty is shown in this work which will contribute in paving a path for synthesizing the ideal inorganic HTM for PSCs.

Augmented Reality (AR) has in the past decade shown great potential in manufacturing, specifically AR guided assembly. This is the use of AR to provide product assembly instructions to factory workers. AR guided assembly has shown to outperform conventional (paper based) and virtual based methods of instruction delivery in terms of accuracy and time. However, authoring the AR content displayed to the worker is difficult and time consuming. The main challenge for an AR authoring tool is to allow the author the ability to register the content intuitively without having to understand complicated AR concepts. Many authoring tools have tried to overcome this challenge but have been unable to sufficiently create a good working abstraction for the novice author. The work presented in this paper focused on creating AR work instructions for bench top assemblies using a novel form of authoring termed expert demonstration. The working concept is that an expert is recorded performing the assembly steps by a computer vision system. The recording is then automatically processed to generate AR work instructions. Augmented Reality via Expert Demonstration Authoring (AREDA) is the name of the representative software developed in this research. AREDA is divided into two phases: the demonstration phase and refinement phase. Using computer vision algorithms along with a novel skin detection algorithm known as Particle Swarm Optimized Gaussian Mixture Model, the demonstration phase was created. This phase takes 3D point clouds of assembly sequences and converts them into ordered 3D parts along with their transformations. The refinement phase then allows a user to modify the automatically generated AR work instructions to fix errors and add useful virtual content (textual instructions). Finally, three use cases are presented using AREDA to generate the work instructions. Through these use cases, this paper shows the significance of the expert demonstration authoring approach.

The native hepatocellular cancer (HCC) microenvironment is characterized by more hypoxic, hypoglycemic, and acidic conditions than those used in standard cell culture. This study aimed to investigate whether HCC cells cultured in more native conditions have an altered phenotype and drug sensitivity compared to those cultured in standard conditions. Six HCC cell lines were cultured in "standard" (21% O2, 25 mM glucose) or more "native" (1% O2, 5 mM glucose, 10 mM lactate) conditions. Cells were assessed for growth rates, cell cycle distribution, relevant metabolite and protein levels, genome-wide gene expression, mitochondrial DNA sequence and sensitivity to relevant drugs. Many differences in cellular and molecular phenotypes and drug sensitivity were observed between the cells. HCC cells cultured in native conditions had slower doubling times, increased HK2 and GLUT, lower PHDA and ATP levels, and mutations in mitochondrial DNA. Thirty-one genes, including the hypoxia-associated NDRG1, were differentially expressed between the cells. HCC patients in The Cancer Genome Atlas (TCGA) with tumors with a high score based on these 31 genes had a poorer prognosis than those with a low score (p = 0.002). From 90 comparisons of drug sensitivity, increased resistance and sensitivity for cells cultured in native conditions was observed in 14 (16%) and 8 (9%) comparisons respectively. In conclusion, cells cultured in more native conditions can have a more glycolytic and aggressive phenotype and varied drug sensitivity to those cultured in standard conditions, and may provide new insights to understanding tumor biology and drug development.

Nanomaterials have gained a lot of interest due to their application in various fields. Tin oxide (SnO2) is an important n-type wide band-gap semiconductor in the field of gas sensing devices due to its chemical and mechanical stability. Here, SnO2 nanoparticles were synthesized by a simple chemical co-precipitation method followed by annealing the obtained nanoparticles at different temperatures. Several characterization techniques like powder X-ray Diffraction, Scanning Electron Microscope, Energy-Dispersive X-Ray spectroscopy, and Ultraviolet–Visible spectroscopy, Fourier Transform Infrared Spectroscopy were carried out to analyze the structure, size, morphology, elemental composition and optical properties of the prepared SnO2 nanoparticles.

Banana bunchy top virus is considered to be the most economically destructive pathogens of banana that causes severe economic loss in banana plantations worldwide, including India. In this present study we have developed an improved electrochemical ELISA for detection of Banana bunchy top virus (BBTV). For enhanced and accurate detection we have used cadmium selenide (CdSe) quantum dots (QDs) as signal amplifiers. Experiments in this study were performed using primary antibody raised from recombinant coat protein of BBTV. CdSe QDs could significantly amplify the electrical signals in this assay and make the method appropriate for lab use. The result of electrical conduction showed the difference of impedance between the healthy and diseased sample of the order of ~ 100 Ω. The electrochemical ELISA could detect the virus in plant sap up to dilution of 1:25 as compared to 1:10 of conventional ELISA.

Nanomaterials synthesis using natural sources is the technology to up come with advanced materials through extracts of plant, microorganisms, poultry waste etc. In this study, the authors report the synthesis of porous carbon nanotubes using high‐temperature decomposition technique facilitated by cobalt salt using chicken fats, a poultry waste as a precursor. Since chicken fats contain fatty acids which can decompose into short hydrocarbon chains and cobalt can act as the catalyst. The formation of carbon nanotubes was confirmed by Raman spectra, peaks at 1580 and 1350.46 cm(−1) confirmed the graphite mode G‐band and structural imperfections defect mode D‐band, respectively. Transmission electron microscopy showed the formation of tube‐like structures. Nitrogen adsorption–desorption studies showed the high‐surface area of 418.1 m(2) g(−1) with an estimated pore diameter of 8.1 nm. Thermogravimetry analysis–derivative thermogravimetric analysis–differential thermal analysis showed the instant weight loss at 517°C attributed to the rapid combustion of nanotubes. A vibrating‐sample magnetometer showed the paramagnetic nature of the so‐formed carbon nanotubes formed.

Highly transparent AZO (Al0.02Zn0.98O) films were deposited on p-type Si (100) using RF magnetron sputtering and then sintered at different temperatures (100 °C, 300 °C, 500 °C, and 600 °C). Structural properties of these films were analyzed and compared using XRD, SEM and AFM. Further, this work investigates the electrical properties of different types of Schottky junctions made with Gold metal contacts on these thin films. With the increasing fabrication temperature, both the optical band gap as well as the ideality factor were found to be decreasing. Impact of temperature variation on potential barrier of Schottky diodes and carrier concentration were also studied.

As the required energy demand of humans keep increasing rapidly, the quest for developing new and efficient alternative energy resources progresses. Keeping the future energy crisis in mind, solar cells, particularly the low-cost dye and quantum dot sensitized solar cells seem to be a promising solution. Using solid polymer electrolyte in such solar cells proves to be a viable alternative as it contributes to the overall stability of the cell. However, there are certain details pertaining to solar cells where polymer electrolyte is used which have not yet been discussed in length. In this paper, we discuss the polarization effect of PEO-based quasi-solid electrolyte in DSSC and QDSC.

Synthesis of colloidal semiconductor quantum dots (QDs) has become a major research area in the field of material science. Over the last two decades QDs have been employed successfully in sensitizing the mesoporous semiconductors like TiO2, ZnO etc. in various configurations thus giving birth to a new branch of low cost solar cells known as quantum dot sensitized solar cells (QDSSCs). In this paper we report low temperature synthesis of core-shell CdSe-CdS quantum dots (QDs) using wet chemical technique. A quantum dot solar cell (QDSC) was also prepared with the core-shell QDs as working electrode and a well explored solid polymer electrolyte. The QDSC was characterized and its stability was monitored for a period of two months in laboratory conditions.

This paper reports the mixed (ionic + electronic) conducting behavior of a copper iodide (CuI) dispersed composite polymer electrolyte system with the help of various characterization techniques. The composite polymer electrolyte films were prepared with different wt.% of CuI, dispersed in a host polymer-salt complex by the solution cast technique. Prepared films were then subjected to various characterization techniques for analysis. X-ray diffraction and Fourier transform infrared spectroscopy were performed to verify the composite nature of the prepared samples. The conductivity and dielectric constant of each sample were analyzed with the help of complex impedance spectroscopy. The dielectric permittivity ( $$ \varepsilon^{\prime} $$ ), dielectric loss ( $$ \varepsilon^{\prime\prime} $$ ), real ( $$ M^{\prime} $$ ) and imaginary ( $$ M^{\prime\prime} $$ ) parts of the electric modulus were also calculated to understand the ion transport mechanism. Transference number of ions ( $$ t_{\rm{ion}} $$ ) was calculated by a polarization technique. Finally, the concentration (n) and mobility (μ) of charge carriers were calculated to explain the changes in conductivity of CuI dispersed polymer films. We observed that the conductivity pattern of the samples predominantly depends on the concentration of charge carriers.

In the present work dye sensitized solar cells were fabricated using natural pigment based dye extracted from different fruits as ‘sensitizer’. The photovoltaic properties of FTO coated thin film and extracted natural dyes were studied using UV–vis-NIR spectroscope. FTO coated subtract showed complete transmittance above 350 nm wavelength that is wide-ranging visible region and above wavelength, which is the desired property for solar cells. The extracted fruits and plants dye showed absorption up to 600 nm wavelength of incident light with wide range abssorption. The TiO2 thin films were prepared on FTO coated conducting substrate using doctor blade technique as photo anode while fruits and plants dye extracted in ethanol was used as sensitizes. The fabricated solar cells were characterized using Keithley source meter which shows that photovoltaic performance is relatively compared with popular expensive dyes i.e. N3, black and ruthenium.

In this work, solution cast method was adapted for the preparation of 1-ethyl-3-methylimidazolium dicyanamide (EMImDCN)-doped solid polymer electrolyte. Optimum composition of polymer electrolyte (polyethylene oxide + sodium iodide) was treated as the host polymer. The ionic conductivity was further enhanced by adding low-viscosity ionic liquid (IL) EMImDCN. Electrical, thermal, dielectric, and photoelectrochemical properties of polymer host and IL-doped solid polymer electrolyte (ILDPE) are presented in detail. An electrochemical device, that is, dye-sensitized solar cell was fabricated using maximum conducting ILDPE film, which shows short-circuit current density of 0.118 mA/cm2, open-circuit voltage of 0.71 V, and overall efficiency of 0.061% at 1 sun condition.

Poly(vinylpyrrolidone) (PVP) complexed with sodium iodide (NaI) is synthesized to investigate the ionic conductivity of alkaline-based polymer electrolytes. In this article, we report the modification of electrical properties of a new ion-conducting polymer electrolyte, namely, PVP complexed with NaI. Modification of polymer electrolyte was carried out before and after the exposure of films by bombarding them at different fluences with respect to Li3+ ion beam at 60 MeV. The preparation and detailed characterization of PVP:NaI is being reported. Further, a correlation with conductivity and dielectric constant has also been established. The modulation in the conductivity is explained in terms of number of charge carriers ( n) and its mobility ( μ), which confirms the behavior of the polymer electrolyte as an alternative strategy to improve the conductivity.

Polymer electrolyte films based on poly(ethylene oxide) doped with salt sodium nitrate and ionic liquid (IL; 1-ethyl 3-methylimidazolium thiocyanate) have been prepared and characterized by differential scanning calorimetry (DSC) and impedance spectroscopy. The relative percentage of crystallinity of polymer electrolytes has been calculated by using DSC thermograms and electrical properties by using impedance spectroscopy. The incorporation of IL in polymer matrix increases the conductivity of polymer electrolyte. The maximum value of ionic conductivity of polymer electrolyte is found to be 1.93 × 10−4 S m−1 with 9 wt% IL.

The sole aim of the present article is to develop an ionic liquid (IL)-doped solid polymer electrolyte for an electrochemical double-layer capacitor (EDLC). A solution cast technique was adopted to develop a solid polymer electrolyte of poly (vinylidene fluoride-co-hexafluoropropylene) as host polymer and low-viscosity IL (1-ethyl-3-methylimidazolium thiocyanate) as dopant. Electrochemical impedance spectroscopy measurement showed a six orders of magnitude enhancement in conductivity ( σ) by IL doping. A linear sweep voltammetric investigation of the electrolyte films exhibited a good electrochemical stability window of 3.6 V. Polarized optical microscopy of the synthesized films revealed a reduction in crystallinity by IL doping. Infrared spectroscopy further affirms the composite nature of the film. The maximum conductivity value of 2.65 mS/cm is obtained for 80% of the ionic-doped system. Using maximum conductivity film and porous carbon-based electrodes, we have developed EDLCs that show a specific capacitance value of 2.36 F/g.

The present investigation deals with the preparation of multi-walled carbon nanotube (MWCNT)-doped plasticized polymer electrolyte. The nanocomposite has been prepared using solution casting method. Complex impedance spectroscopy study revealed the utmost room temperature conductivity of 5.6 × 10−4 S/cm when optimized plasticized polymer electrolyte (poly(ethyl methacrylate)+30% sodium iodide+60% ethylene carbonate) was doped with 7% MWCNT. Temperature dependence of conductivity showed Arrhenius behavior. The surface morphology and crystalline–amorphous deviation of the composite was observed using scanning electron microscope. Perfect complexation of various components of the composite was confirmed from Fourier-transform infrared spectroscopy and X-ray diffraction (XRD) data. The transference number measurement was done to calculate the proportionate amount of ionic and electronic conductivity. A dye sensitized solar cell has been fabricated using maximum ionic conductivity of solid polymer electrolyte and its electrical parameters measured at 1 sun condition.