Structural and optical properties of inorganic–organic hybrid material of acetanilide tetrachloromercurate(II)

The crystal growth of acetanilide tetrachloromercurate(II), an inorganic–organic hybrid derivative has been achieved by solution growth through slow cooling method. The X-ray diffraction structural analysis of the hybrid material results that the compound exist in orthorhombic space group P2₁2₁2₁ with lattice parameters; a?=?13.111(2) ?, b?=?11.311(2) ?, c?=?8.355(6) ?, α?=?β?=?γ?=?90° and unit cell volume?=?1436.24 ?³. The fourier transform infrared spectroscopy profile shows that the C–C and C–N stretching modes of acetanilide ring and the observed spectra falls in mid-infrared range υ(526–2850) cm^?1. The field emission scanning electron microscope image confirms that the hybrid material has a prismatic shape with an average granular size of ~25 nm. The energy dispersive X-ray spectroscopy analyzes the elemental proportions of the hybrid materials. Transmission electron microscopy image shows the narrow distribution of nano-spatial agglomeration of secondary interactions in inorganic–organic particles. The optical band gap (Eg?=?3.75 eV) as calculated by linear fit profile of Tauc plot for allowed transition predicts that the hybrid material has potential applications in solar cells, electronic and opto-electronic devices.     

Analysis of SCF under sales promotional schemes: an application of interpretive structural modelling approach

In the competitive market of today, supply chain flexibility (SCF) plays crucial way to address various supply chain uncertainties. But, in diverse situations, the supply chain needs different types of flexibilities. This paper analyses the flexibility of an automobile supply chain under sales promotional schemes (SPS) to meet the demand uncertainty. Taking the opinion of supply chain experts from automobile original equipment manufacturers (OEM’s), 14 SCF strategies have been identified and then using interpretive structural modelling (ISM) on the conducted survey, their interrelationships are established and a hierarchical model is developed. MICMAC analysis is done to classify the strategies into four categories viz. autonomous, dependent, linkage and independent strategies, which are based on their driving and dependence powers. Sensitivity analysis has been conducted to check the stability of the model. The thorough exposition of the model presents a handful of insights to supply chain managers to know the most important strategies affecting each other. The study helps in bridging the SCF with SPS, a huge gap existing in the literature.     

Effect of CoCl<Subscript>2</Subscript>–BaCl<Subscript>2</Subscript> fillers on morphology,dielectric constant and conductivity of PVDF composite for pressure sensing application

This present study focuses on the effect of addition of CoCl₂–BaCl₂ fillers on the β phase formation and dielectric constant in the PVDF composite films. The pristine and filler based PVDF films were prepared using solution casting technique. XRD analysis were carried out to investigate the crystalline structure in the prepared composite films. The surface morphology of the films were observed using SEM indicating the formation of agglormated structures. The UV–Vis absorption spectrum was obtained to investigate the effect of filler concentration on the optical band gap. The decrease in optical band gap with increase in filler concentration was confirmed from Tauc plot. The incorporation of filler significantly improved the ac conductivity. The dielectric study reveals the increase in value of dielectric constant from 10.8 to 42.3 as the filler content increased from 0 to 12 wt%. A pressure measurement set up was developed and voltage output was measured from the PVDF thin film sensor for variation in applied pressure.     

Thermoreversible nanoethosomal gel for the intranasal delivery of Eletriptan hydrobromide

The objective of the current study was to formulate and characterize thermoreversible gel of Eletriptan Hydrobromide for brain targeting via the intranasal route. Ethosomes were prepared by 3² factorial design with two independent variables (concentration of soya lecithin and ethanol) and two response variables [percent entrapment efficiency and vesicle size (nm)] using ethanol injection method. Formulated ethosomes were evaluated for preliminary microscopic examination followed by percent drug entrapment efficiency, vesicle size analysis, zeta potential, polydispersibility index and Transmission electron microscopy (TEM). TEM confirms spherical morphology of ethosomes, whereas Malvern zeta sizer confirms that the vesicle size was in the range of 191 ± 6.55–381.3 ± 61.0 nm. Ethosomes were incorporated in gel using poloxamer 407 and carbopol 934 as thermoreversible and mucoadhesive polymers, respectively. Ethosomal gels were evaluated for their pH, viscosity, mucoadhesive strength, in vitro drug release and ex vivo drug permeation through the sheep nasal mucosa. Mucoadhesive strength and pH was found to be 4400 ± 45 to 5500 ± 78.10 dynes/cm² and 6.0 ± 0.3 to 6.2 ± 0.1, respectively. In-vitro drug release from the optimized ethosomal gel formulation (G4) was found to be almost 100 % and ex vivo permeation of 4980 µg/ml with a permeability coefficient of 11.94 ± 0.04 × 10^?5 cm/s after 24 h. Histopathological study of the nasal mucosa confirmed non-toxic nature of ethosomal gels. Formulated EH loaded ethosomal thermoreversible gel could serve as the better alternative for the brain targeting via the intranasal route which in turn could subsequently improve its bioavailability.     

A secure n-secret based client authentication protocol for 802.11 WLANs

Authentication has strong impact on the overall security model of every information system. Various authentication techniques are available for restricting the access of unauthorized users to the enterprise scale networks. IEEE 802.1X defines a secure and reliable authentication framework for 802.11 WLANs, where Extensible Authentication Protocol (EAP) provides the base to this architecture. EAP is a generic architectural framework which supports extensibility by incorporating the new and improved authentication schemes, which are based on different types of credentials. Currently there exist a number of EAP and Non-EAP methods with varying level of security and complexity. In this work, we have designed a new n-secret based authentication scheme referred here as Personal Dialogue Based Authentication, for the client authentication to the network. It is a Transport Layer Security (TLS) protected authentication protocol, which will be executed inside the secure TLS tunnel for providing the privacy and credential security to the wireless client. The developed authentication protocol has a reasonable set of features like; strong security, user privacy, simplicity and extensibility. For the formal analysis of the protocol we have used SPAN–AVISAP model checker on Ubuntu platform for validating the realization of the specified security goals. The experimental results obtained by simulation performed with the Automated Validation of Internet Security Protocols and Applications (AVISPA) tool shows that our protocol is efficient and secured.

     

A dictionary matrix generation based compression and bitwise embedding mechanisms for ECG signal classification

The Electrocardiogram (ECG) signal processing is one of the exciting research areas in recent days. Ensuring security to the patient’s confidential information is a demanding critical task in many healthcare systems. So, the traditional works developed the security mechanisms for embedding the original ECG signal with the image, audio, or video. But, it does not focus on reducing the size of the original message before transmitting it to others. Also, it has significant limitations of inefficient security, increased complexity, and reduced classification accuracy. To rectify this issue, our research proposed the new embedding mechanism to improve the security of patient’s health information. In this system, the original ECG signals compressed at the initial stage by using the proposed Dictionary Matrix Generation (DMG) algorithm. Then, the compressed signals embedded within the cover image by using the Bitwise Embedding (BE) mechanism. At the receiver side, the bedded goal is de-embedded and decompressed by using the DMG and BE algorithms. The features such as spectral and peak values of the signal are extracted for increasing the efficiency of classification. Classification and detection of abnormality present in ECG signal of patient is the most essential part. To achieve this, we proposed the Modified Dynamic Classification (MDC) algorithm based on the features. In this work, the novelty is implemented in the compression, embedding, and classification stages. The proposed system reduces the data loss during transmission, memory storage and time complexity. The overall process evaluated by using PTB diagnostic ECG database. In experiments, the proposed classification technique provides the accuracy of 98.39% and it proved that the proposed method had highest performances than existing methods such as PNN, SVM and RF classification.

     

Low profile four‐port super‐wideband multiple‐input‐multiple‐output antenna with triple band rejection characteristics

A quad‐port planar multiple‐input‐multiple‐output (MIMO) antenna possessing super‐wideband (SWB) operational features and triple‐band rejection characteristics is designed. The proposed MIMO configuration consists of four modified‐elliptical‐self‐complementary‐antenna (MESCA) elements, which are excited by tapered co‐planar waveguide (TCPW) feed lines. A radiator‐matched complementary slot is present in the ground conductor patch of each MESCA element. The proposed MIMO antenna exhibits a bandwidth ratio of 36:1 (|S₁₁| < ?10 dB; 0.97‐35 GHz). Further, a step‐like slit‐resonator is etched in the radiator to eliminate interferences at 3.5 GHz. A hexagonal shaped complementary split ring resonator (CSRR) is also loaded on the MESCA radiator to remove interferences at 5.5 and 8.5 GHz. The MIMO antenna is fabricated on FR‐4 substrate of size 63 × 63 mm² and experimental results are found in good agreement with the simulated results. The MIMO antenna exhibits inter‐element isolation >17 dB and envelope correlation coefficient (ECC) <0.01 at all the four ports.     

In-house development of co-fireable thick film silver conductor for LTCC applications

The rapidly growing wireless industry needs new high performance materials to build low loss, high density, and thermally stable integrated packages. Applications include automotive safety, control, global positioning system (GPS) mapping and entertainment, multifunctional portable phones, video and data transmission through wireless local area network (WLAN) etc. Recently, low temperature co-fired ceramics (LTCC) technology is referred as a key approach for smart packaging. Although its use has been initiated in the telecommunication field due to the excellent dielectric properties of the LTCC tapes, its application areas have been diversified recently. In the present work, the attempt has been made towards the development of thick film silver conductor composition compatible with available LTCC tapes (DuPont DP-951AX). The physical, microstructural, and electrical properties of the pastes prepared with different compositions are presented in this paper.