Search

This work presents the synthesis of Y2O3:Eu3+,xCa2+ (x = 0 mol%, 1 mol%, 3 mol%, 5 mol%, 7 mol%, 9 mol%, 11 mol% of Ca2+) nanophosphor with enhanced photoluminescence properties through a facile solution combustion method for optoelectronic, display, and lighting applications. The X-ray diffraction patterns (XRD) of the proposed nanophosphor reveal its structural properties and crystalline nature. The transmission electron microscope results (TEM) confirm the change in the shape of the particle and aggregation of particles after co-doping with Ca2+. Fourier transform infra-red spectroscopy (FTIR) and Raman vibrations also confirm the presence of Y-O vibration and subsequently explain the crystalline nature, structural properties, and purity of the samples. All the synthesized nanophosphors samples emit intense red emission at 613 nm (5D0→7F2) under excitation with 235, 394 and 466 nm wavelengths of Eu3+ ions. The photoluminescence (PL) emission spectra excited with 235 nm illustrates the highest emission peak with two other emission peaks excited with 466 and 394 nm that is 1.4 times higher than 466 nm and 1.9 times enhance by 394 nm wavelength, respectively. The emission intensity of Y2O3:Eu3+,xCa2+ (5 mol%) has been increased 8-fold as compared to Eu:Y2O3. Doping with Ca2+ ions enhances the emission intensity of Eu:Y2O3 nanophosphors due to an increase in energy transfer in Ca2+→Eu3+ through asymmetry in the crystal field and by introduction of radiative defect centers through oxygen vacancies in the yttria matrix. It has also been observed the optical band gap and the lifetime of the 5D0 level of Eu3+ ions in Y2O3:Eu3+,xCa2+ nanophosphor sample gets changed with a doping concentration of Ca2+ ions. Nanophosphor also reveals high thermal stability and quantum yield as estimating activation energy 0.25 eV and 81%, respectively. CIE, CCT, and color purity values (>98%) show an improved red-emitting nanophosphor in the warm region of light, which makes this material superior with a specific potential application for UV-based white LEDs with security ink, display devices, and various other optoelectronics devices.

Herein, we report the electrochemical detection of roxarsone (ROX) on a two-dimensional (2D) activated carbon (AC)-modified glassy carbon electrode (GCE). Meso/microporous 2D-AC is synthesized from a natural biomass Desmostachya bipinnata, commonly known as Kusha in India. This environment-friendly material is synthesized by chemical activation using potassium hydroxide (KOH) and used as a sensitive electrochemical platform for the determination of ROX. It is an arsenic-based medicine, also used as a coccidiostat drug. It is widely used in poultry production as a feed additive to increase weight gain and improve feed efficiency. Long-term exposure to arsenic leads to serious health problems in humans and demands an urgent call for sensitive detection of ROX. Therefore, the green synthesis of 2D-AC is introduced as new carbon support for the electrochemical sensing of ROX. It provides a large surface area and efficiently supports enhanced electron transfer. Its electrocatalytic activity is seen in potassium ferri/ferrocyanide by cyclic voltammetry, where the 2D-AC-modified GCE delivered five to six times higher electrochemical performance as compared to the unmodified GCE. Electrochemical impedance spectroscopy is also performed to show that the prepared material has faster electron transfer and permits a diffusion-controlled process. It works well in real samples and also on disposable screen-printed carbon electrodes, thereby showing great potential for its application in clinical diagnosis. Our results exemplify a modest and innovative style for the synthesis of excellent electrode material in the electrochemical sensing platform and thus offer an inexpensive and highly sensitive novel approach for the electrochemical sensing of ROX and other similar drugs.

A comparative study has been performed in the synthesis of the perovskite material and also its deposition by the one step and two step dipping methods has been studied and compared. The perovskite material prepared by both the methods have undergone through the characterization techniques of scanning electron microscopy (SEM) and UV–Vis absorbance spectroscopy. The J-V measurements with Keithley source meter has also been performed, which verifies the successful fabrication of the PSC in ambient air with single step as well sequential deposition of perovskite using PEDOT: PSS as HTM in each case.

Marigold flower (MG; Tagetes erecta) derived Graphene quantum dots (GQDs) have been successfully reported for the fabrication of supercapacitor electrodes in charge storage devices. The GQDs have been synthesized through a hydrothermal route using biomass viz. Waste material (MG) without adding any hazardous chemicals. The successful formation of GQDs as elaborated has been confirmed by various analytical characterization techniques. The as-synthesized GQDs have been electrodeposited on the Ni foil (working electrode) with the help of PVDF (binder) and subsequently, cyclic voltammetry (CV) has been conducted to access specific capacitance, energy density, and other parameters. Moreover, the galvanometric charge/discharge (GCD) technique has been employed due to its accuracy and reliability. Maximum areal specific capacitance has been found as 1.6008 F/cm2 with the current density of 2.0 A/g even after loading a little amount of material on the electrode. The high magnitude of columbic efficiency (160.08), energy density (17.78 Wh/kg), and specific capacitance of 200 F/g at current density 2.0 A/g within a voltage range of −0.55 V to +0.25 V in 2 M KOH electrolyte solution indicate a good electrocapacitive performance of the as-synthesized material. Moreover, the as-synthesized GQDs have shown excellent capacitive retention after 1000th cycles which clearly embarks its sustainable electrocapacitive nature and henceforth offers outstanding potential for the applications in energy storage devices like supercapacitors.

The aim of this study was to examine the determinants of urban poverty in the case of Female headed household of Ibinat town. Both primary and secondary data sources are used. Primary data was collected directly from sample respondents of female headed households. To collect the data structured questionnaire was prepared and distributed for the respondents. To select the appropriate sample households, simple random sampling technique was used. A total of 180female headed households have been taken as a sample. To analyze the collected data both descriptive and econometric model have been used. To identify the status of poverty Foster- Greer –Thorbecke measures of poverty was used. The headcount ratio(Po) shows that about 45 percent of the sampled female headed households are below the poverty line. The poverty gap index (P1) indicates that average poverty gap in the sample living below the poverty line is 11%. The severity of the poverty indicates that the poorest people in Ibinat town are 9 percent worse off compared to those total households living below the poverty line. To identify the determinants of urban poverty in the case of female headed household, binary logistic regression model was used. The results of logistic regression revealed that family size, age of the household head, number of dependent family member and access to credit are significantly affecting urban poverty. It is recommended to policy makers to act accordingly on credit policies, family planning activities and investments (both public and private. Government policies should encourage financial institutions (both formal and informal) so that households get an access to credit and reduce poverty. There should be family planning practice by local level governments to increase the number of family size, since an increase in family size is negatively associated with household poverty. To reduce the number of dependent people government and other stakeholders should encourage investment in the town so that those dependent people will be employed and generate income. If every family member is generating income, household poverty will decline.

Correct localization of the sacral hiatus is essential for administering a successful caudal epidural block. The present study was undertaken to find out the anatomical variations of sacral hiatus by a metrical method so that it could help anaesthesiologists in the clinical field.The study was performed on 140 (83 male and 57 female) adult human sacra. Various parameters of the sacrum studied were as follows: the shape of the hiatus, length of the sacral hiatus, transverse width at the base and anteroposterior diameter at the level of the apex. For each parameter, the mean value (calculated in mm), standard deviation, range and percentage of bones identified correctly were calculated.Various shapes of sacral hiatus were observed, including inverted "U" in 73 (52.14%), inverted "V" in 33 (23.57%), irregular in 10 (7.14%), elongated in 10 (7.14%) and dumbbell-shaped in 12 (8.57%). Absent sacral hiatus was observed in two (1.43%) specimens. The mean value for the length of sacral hiatus from the apex to the midpoint of the base was found to be 23.26 mm in males and 22.38 mm in females. However, the parameter was found to be statistically not significant. The mean value for transverse width at the base of hiatus was found to be 14.19 mm in males and 13.54 mm in females. The mean value for the anteroposterior diameter of the sacral canal at the apex was found to be 4.57 mm in males and 4.32 mm in females. Both the above parameters were found to be statistically not significant.The anatomical knowledge of sacral hiatus and its variations are important in caudal epidural anaesthesia, and it may improve the success rate of caudal epidural anaesthesia.

Introduction: The muscular segments which overlie the epicardial arteries are termed as myocardial bridges and the artery which travels through them are termed as tunnel arteries. These tunnel arteries get compressed during the systolic compression of the heart, thus partially or completely blocking the blood supply to the corresponding areas. Aim & Objectives: To assess the impact of these myocardial bridges on the proximal segment of the myocardial arteries. Methodology: The present study was cadaveric-based cross-sectional study. A total of 22 hearts which showed the presence of myocardial bridges were collected from two sources namely: cadaver dissections, autopsy. The hearts were clean and numbered. This was followed by fixation, dehydration, clearing, embedding, block formation, section cutting and staining. Result: The present study showed that there is a significant thickening in the tunica intima of the proximal to bridge segment of the coronary artery. The present study also noted that there is a marked thinning of the tunica media of the same segment. Conclusion: The present study concludes that there is a marked hyperplasia in the proximal segment of the myocardial bridges under tunica intima.

Herein, we demonstrate the fabrication of highly capacitive activated carbon (AC) using a bio-waste Kusha grass (Desmostachya bipinnata), by employing a chemical process followed by activation through KOH. The as-synthesized few-layered activated carbon has been confirmed through X-ray powder diffraction, transmission electron microscopy, and Raman spectroscopy techniques. The chemical environment of the as-prepared sample has been accessed through FTIR and UV–visible spectroscopy. The surface area and porosity of the as-synthesized material have been accessed through the Brunauer–Emmett–Teller method. All the electrochemical measurements have been performed through cyclic voltammetry and galvanometric charging/discharging (GCD) method, but primarily, we focus on GCD due to the accuracy of the technique. Moreover, the as-synthesized AC material shows a maximum specific capacitance as 218 F g−1 in the potential window ranging from − 0.35 to + 0.45 V. Also, the AC exhibits an excellent energy density of ~ 19.3 Wh kg−1 and power density of ~ 277.92 W kg−1, respectively, in the same operating potential window. It has also shown very good capacitance retention capability even after 5000th cycles. The fabricated supercapacitor shows a good energy density and power density, respectively, and good retention in capacitance at remarkably higher charging/discharging rates with excellent cycling stability. Henceforth, bio-waste Kusha grass-derived activated carbon (DP-AC) shows good promise and can be applied in supercapacitor applications due to its outstanding electrochemical properties. Herein, we envision that our results illustrate a simple and innovative approach to synthesize a bio-waste Kusha grass-derived activated carbon (DP-AC) as an emerging supercapacitor electrode material and widen its practical application in electrochemical energy storage fields.

The present article illustrates the green synthesis of novel carbon quantum dots (CQDs) from biomass viz. Tagetes erecta (TE), and subsequently fabrication of a metal ion probe for the sensing of Fe3+ in real samples. TE-derived CQDs (TE-CQDs) have been synthesized by a facile, eco-friendly, bottom-up hydrothermal approach using TE as a carbon source. The successful synthesis and proper phase formation of the envisaged material has been confirmed by various characterization techniques (Raman, XRD, XPS, TEM, and EDS). Notably, the green synthesized TE-CQDs show biocompatibility, good solubility in aqueous media, and non-toxicity. The as-synthesized TE-CQDs show an intense photoluminescence peak at 425 nm and exhibit excitation dependent photoluminescence behavior. The proposed TE-CQD-based probe offers a remarkable fluorescence (FL) quenching for Fe3+ with high selectivity (Kq ∼ 10.022 × 1013 M−1 s−1) and a sensitive/rapid response in a linear concentration range 0–90 μM (regression coefficient R2 ∼ 0.99) for the detection of Fe3+. The limit of detection (LOD) of the probe for Fe3+ has been found as 0.37 μM in the standard solution. It has further been applied for the detection of Fe3+ in real samples (human blood serum) and displays good performance with LOD ∼ 0.36 μM. The proposed TE-CQD-based ion sensing probe has potential prospects to be used effectively in biological studies and clinical diagnosis.

In recent years, Perovskite solar cells (PSC) have garnered immense popularity in the field of photovoltaics, due to its efficiency comparable to silicon solar cells and its ease of processing makes it cost effective. Owing to the vast scope of organic–inorganic metal halides in the field of Perovskite Solar Cell, we have designed and fabricated a sandwiched methyl ammonium lead iodide (CH3NH3PbI3) based PSC using PEDOT: PSS as hole transport material (HTM) in room ambient condition. The PSC with architecture of FTO/TiO2/Perovskite/PEDOT: PSS/Pt, show a high efficiency of 15.24% at one sun condition. Owing to the fact that most of PSC are unstable at room ambient, our PSC affirms a stability of two hours, at room environment. In recent years, for the first time such high efficiency of PSC is reported in sandwich structure in ambient conditions. Since it is completely based on solution processing with no usage of vacuum deposition, it is very cost effective.

The Nitrogen (N) functionalized graphene (NG) has been investigated to confirm its suitability for the detection of toxic Arsenic (As) present in the water, causing health hazards. The calculations have been performed using density functional theory and NEGF formalism. Here, a monolayer graphene has been modeled and functionalized by substituting its carbon with nitrogen. The computed binding energy for the adsorption of As reveals a strong interaction between the adsorbate and adsorbent. The band structure and current-voltage relationship has been analysed to examine the detection ability of the modeled NG towards the Arsenic. Band opening is the resultant of introducing As near to NG, resulted in to decrement of current in I-V characteristics in comparison to its pristine counterpart. To confirm the suitability of proposed NG as a promising candidate for detection of heavy metal Arsenic in the water, it has been observed that that the NG has sufficient binding energy, along with variation in electronic and transport properties with a reasonably short recovery time of 5.5 ms and 21.3 ms in vacuum and aqueous environment, respectively.

Herein, we report a voltammetric method for the nanomolar detection of cefixime, a third-generation antibiotic. The determination of cefixime is validated on a glassy carbon electrode (GCE) as well as on a screen-printed carbon electrode (SPCE). In the present study, we have reported a facile "one step simple hydrothermal synthesis" of MoS2 quantum dots and with the oxidation of aurochloric acid for the further formation of an MoS2 QD-AuNP composite. The as-synthesized nanocomposite was characterized via UV-Vis spectroscopy, FTIR spectroscopy, XRD, TEM and EDX techniques, and further applied in the modification of working electrodes, showing excellent electroactivity. The sensing of cefixime was done via cyclic and differential pulse voltammetry techniques. The presence of the only anodic peak in the voltammogram reveals the irreversible oxidation of cefixime in the potential range of about 1.3 ± 0.1 V vs. Ag/AgCl. The study was also performed at different scan rates, which indicate a diffusion-controlled mechanism. The proposed cefixime sensor showed a linear response in the concentration range of 0.33-90.82 μM (at S/N = 3) with a limit of detection (LOD) of 3.9-4.5 nm. The electrochemical sensitivity is calculated as 8.63 μA μM-1 cm-2 and 7.07 μA μM-1 cm-2 in buffer and pharmaceutical formulation (commercially available cefixime tablet), respectively. The effects of several interferents were also investigated. The proposed sensor is effectively used for estimating cefixime in phosphate buffer and the commercially available cefixime tablets with no cross-reactivity or matrix effects and shows a promising prospect for real applications.

Introduction - Spina-bida occulta is a condition in which there is incomplete dorsal midline closure of the osseous tissue, thus spinal cord remains unprotected. We reported a case of total spi Case Report - na bida occulta type 1 of dried specimen of a sacrum during routine osteology teaching of undergraduate. SSBO is a Conclusion - developmental defect and is associated with many other anomalies also .There are many genetic causes which are responsible for SSBO.This is very useful for anesthetist to be aware of this abnormality prior to give epidural anaesthesia to avoid dural puncture.

A series of Eu

We report the toxic gas sensing ability of ZnO Nanowire performed by using Density Functional Theory (DFT) based first principle approach. The ZnO Nanowire with rectangular morphology has been modeled and investigated for its energetic stability, analysed in terms of binding energy. The adsorption of a single molecule of carbon dioxide (CO2) gas on the fully relaxed rectangular ZnO Nanowire has been analysed through its dynamic response discussed in terms of conductance. The sensing ability has been evaluated further through adsorption energy, electronic band structure, density of states, Mullikan population and current-voltage analysis of the Nanowire. It has been observed that CO2 is physisorbed on the rectangular ZnO Nanowire via van-der-Waals interaction and relatively shows higher sensitivity of this morphology over other reports, defends this as a good candidate for CO2 sensing using ZnO structures.

In this paper an electrochemical sensor for transferrin was developed by anchoring molecularly imprinted polymers (MIPs) on surface of gold coated quartz crystal microbalance (EQCM) using starch nanoparticles (Starch NP) - reduced graphene oxide (RGO) nanocomposite as polymeric format for first time. The nano MIP sensor was developed by electrodeposition of Starch NP-RGO nanocomposite on EQCM electrode in presence of template transferrin. Due to the location of imprinted sites on surface and high specific surface area, analyte molecules have good accessibility and high binding affinity to template molecule thus yielding highly sensitive and efficient signal. Under optimized conditions, the change in frequency of modified electrode coated quartz crystal electrode showed linear dynamic ranges (1–10 μM) using EQCM method. The limit of detection 20 ppb (EQCM) without any cross reactivity and matrix effect indicates high sensitivity and selectivity for transferrin. The sensor was appreciably selective to transferrin in presence of possible interferrents. The relative standard deviation for determination was 5.23%. On the basis of speediness and sensitivity, the sensor is reusable and shows a great improvement in selectivity and adsorption capacity over other sensors.

In this paper, we explain the electrochemical sensing of commercially available pioglitazone hydrochloride (PIOZ) tablets on a nitrogen (N) doped r-GO (Nr-GO) modified commercial glassy carbon electrode (GCE) and a commercial screen printed graphite electrode (SPGE). Nr-GO is synthesized by the chemical reduction of graphene oxide (GO) and simultaneous insertion of an N-dopant by hydrazine monohydrate. Pristine GO itself is prepared by chemical exfoliation of bulk graphite. Upon chemical reduction, the exfoliated GO sheets restack together leaving behind the doped N-atom as evidenced by XRD and Raman spectroscopy. The N-atom exists in the pyrrolinic and pyridinic form at the edge of graphitic domains which is confirmed by XPS. The as-synthesized Nr-GO is used for the preparation of electro-active electrodes with the help of the GCE and SPGE. These electrodes have the capability to oxidize PIOZ by a diffusion dominated process as evidenced by the impedance spectroscopic technique. The differential pulse voltammetric responses of different concentrations of PIOZ are assessed over the Nr-GO modified GCE and SPGE, which exhibit better limits of detection (LODs) of 67 nM and 29 nM, respectively, compared to those from earlier reports. These assays exhibit non-interfering capability in the presence of various body interferents at pH = 7.0.

The present work reports a highly efficient Ca doped Eu: Y

Methyl ammonium lead iodide (MAPbI(3)) perovskite materials, have a significant impact in the field of solar cells. The solar-to power conversion efficiency of PSC, achieved so far is quite high as compared to the organic solar cells and dye sensitized solar cells. in this study we report the synthesis of perovskite (MAPbI(3)), the hole transport material (HTM) Nickel oxide and their application in the fabrication of perovskite solar cell (PSC) at room temperature. NiO has been an effective HTM due to its wideband gap and better carrier mobility. Noticeably, the PSC exhibits a power conversion efficiency (PCE) of 14.04%, which is the best performance reported so far in the sandwich structure employing NiO as HTM, with Voc = 0.78 V, J(sc) = 40 mA/cm(2) and fill factor = 0.45. (C) 2019 Elsevier Ltd. All rights reserved.

Herein, we report a voltammetric method for the nanomolar detection of cefixime, a third-generation antibiotic. The determination of cefixime is validated on a glassy carbon electrode (GCE) as well as on a screen-printed carbon electrode (SPCE). In the present study, we have reported a facile "one step simple hydrothermal synthesis" of MoS2 quantum dots and with the oxidation of aurochloric acid for the further formation of an MoS2 QD-AuNP composite. The as-synthesized nanocomposite was characterized via UV-Vis spectroscopy, FTIR spectroscopy, XRD, TEM and EDX techniques, and further applied in the modification of working electrodes, showing excellent electroactivity. The sensing of cefixime was done via cyclic and differential pulse voltammetry techniques. The presence of the only anodic peak in the voltammogram reveals the irreversible oxidation of cefixime in the potential range of about 1.3 ± 0.1 V vs. Ag/AgCl. The study was also performed at different scan rates, which indicate a diffusion-controlled mechanism. The proposed cefixime sensor showed a linear response in the concentration range of 0.33-90.82 μM (at S/N = 3) with a limit of detection (LOD) of 3.9-4.5 nm. The electrochemical sensitivity is calculated as 8.63 μA μM-1 cm-2 and 7.07 μA μM-1 cm-2 in buffer and pharmaceutical formulation (commercially available cefixime tablet), respectively. The effects of several interferents were also investigated. The proposed sensor is effectively used for estimating cefixime in phosphate buffer and the commercially available cefixime tablets with no cross-reactivity or matrix effects and shows a promising prospect for real applications.

Artificial Intelligence (AI), in general, refers to the machines (or computers) that mimic “cognitive” functions that we associate with our mind, such as “learning” and “solving problem”. New biomarkers derived from medical imaging are being discovered and are then fused with non-imaging biomarkers (such as office, laboratory, physiological, genetic, epidemiological, and clinical-based biomarkers) in a big data framework, to develop AI systems. These systems can support risk prediction and monitoring. This perspective narrative shows the powerful methods of AI for tracking cardiovascular risks. We conclude that AI could potentially become an integral part of the COVID-19 disease management system. Countries, large and small, should join hands with the WHO in building biobanks for scientists around the world to build AI-based platforms for tracking the cardiovascular risk assessment during COVID-19 times and long-term follow-up of the survivors.

This paper presents a series of Ho3+ activated Ca0.5Y1.90-xO3 green-emitting nanophosphors using the facile solution combustion method. X-ray diffraction (XRD) and Transmission electron microscope (TEM) confirm the phase purity, structural morphology with cubic phase, and irregular shape particle with the average particle size of ⁓ 21 nm. Diffuse reflectance spectra of the recorded and band gap estimated by Tauc's equation which is 5.78 eV, 4.90 eV for direct and indirect band gaps for 2 moles % of Ho3+ respectively. Under the excitation of 448 nm wavelength (5I8 → 3G6), the doped samples display characteristic emission of Ho3+ ions correspond to 5S2 → 5I8 (at 551 nm) transition, which fall in a strong green region. The optimal concentration for Ho3+ doping is found as 2 moles %, after this quenching of photoluminescence (PL) intensity occurred and this is accredited due to dipole-dipole interaction. The proposed nanophosphor also displays the good thermal stability with activation energy of 0.23 eV. The nanophosphor confirms the excellent color purity (98%), CRI (98.36 %), and CCT value (5724 K). With this, nanophosphor also exhibits good quantum efficiency of 81.1 % under the 448 nm excitation wavelength. These results direct that the Ho3+ activated Ca0.5Y1.90-xO3 nanophosphor may have potential applicability for green-emitting LEDs, display device and optoelectronic applications.

The present article reports the synthesis and characterization of Eu:Y2O3 nanophosphor (EYN) and EYN dispersed polyvinyl alcohol (PVA) fluorescent film (EYF), with subsequent studies of sensing behavior for the detection of heavy metal ions particularly arsenic ions (As3+) in real water samples. Various characterization techniques have been employed to confirm the successful phase formation/stability of EYF. The maximum emission peak for EYF with excitation wavelength 394 nm has been obtained as 613 nm and hence picked for the demonstration of PL (Photoluminescence) response with arsenic ions solution in natural pH range (at ∼7 pH). Fluorescence intensities of EYF have been found to decrease quickly with As3+ ion contents due to the reduction in the population of Eu3+ ions in the 5D0 level and also due to formation of direct or indirect coordinate bonds with Eu3+. The PL intensity of the EYF nanoprobe has completely been quenched at 260 µg/L concentration of As3+ ions with the limit of detection 57.5 ng/L (= 0.057 ppb = 0.741 nM) with 0-100 µg/L linear range. The values of Ksv have been accessed as 31.2 ×106 M-1 with R2= 0.993 with remarkably high binding affinity KLB 2.32×1010 M-1 as. The selectivity of EYF probe is also investigated for various common cations and ions present in real water samples. Moreover, sensing probe has been examined with different river water samples and shows recovery percent in between 98-105 & maximum % RSD value as 5.76 with n=5 tests. Furthermore, the EYF sensing probe shows a visible color change with the contaminated water under UV-Vis light which useful for the onsite detection of arsenic concentration. Hence, EYF endows a promising pathway for a flexible, portable, low-cost sensing device for the sensitive and selective detection of arsenic ions in real water samples.

In the present paper, we have studied the better performance of zinc oxide (ZnO), gold (Au) and graphene-based SPR biosensor for the detection of pseudomonas and pseudomonas like bacteria. The performance of proposed SPR biosensor is based on theoretical analysis of the sensitivity, detection accuracy, quality parameter and electric field intensity enhancement factor (EFIEF) with angular interrogation method. In this biosensor, prism (BK-7 glass) base is coated with ZnO followed by Au, graphene and different affinity layers, water is used as sensing medium. The advantage of the present biosensor is the hybrid structure of graphene, gold and ZnO with enhanced sensitivity in which the molecular recognition sites on graphene bind strongly the pseudomonas like bacteria with the help of affinity layers. ZnO is responsible for the larger shift in resonance angle that leads a significant enhancement in the sensitivity of the present biosensor. On analyzing the results, we have found that the proposed biosensor has a greater sensitivity of 187.43 deg/RIU, detection accuracy of 2.05 deg-1 and quality parameter of 29.33 RIU-1 as compared to the other reported conventional SPR biosensor for the detection of pseudomonas like bacteria.

In the present paper, we have reported the variation of CaWO4:Eu3+ nano phosphors with different compositions of Li+, (LEC) (Li+ = 2, 5, 7 and 10 at%). The as-prepared (ASP) samples are annealed at 900 °C to eliminate unwanted organic moieties present in the sample and to improve crystallinity. These nanoparticles are characterized by X-ray diffraction (XRD), Thermogravimetric Analysis (TGA), X-ray photoelectron spectroscopy (XPS), Fourier transform IR spectroscopy (FTIR), Raman spectroscopy, photoluminescence studies. FTIR gives the absorption band at ~832 cm−1, which corresponds to antisymmetric vibrations due to O-W-O band in the WO42- tetrahedron. This is also confirmed by the Raman Spectroscopy. CaWO4 has a crystal of the Scheelite type having C4 h point group symmetry and I41/a space group symmetry. The surface/ particle morphology of 900 °C annealed samples studied using Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) and show the formation of nanosheet like structure. Annealed samples of lithium co-doped CaWO4:Eu3+nanoparticles have shown the red luminescence which is attributed due to the strong host contribution and different energy transfers from Li+ ions to host matrix under 392 nm excitations. Li+ ion improves the crystallinity and radiative transition rate and these materials may be potential candidates for white light emitting diodes and may be widely used as optoelectronic materials.