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The growth of the healthcare sector has attracted a lot of interest to biomedical telemetry. Without regular hospital check-ups and follow-up routine check-ups, it is now possible to remotely monitor a patient's physiological indications. This research work proposes an 18 mm3 implanted antenna with a mainly compact volume for biomedical applications. The performance of the antenna is entirely examined in terms of the SAR values, directive gain, Impedance Bandwidth, and reflection coefficient. The substrate material used in proposed antenna is FR4 epoxy resin, as FR4 plays an important part in adding the bandwidth of the antenna and is far cheaper than Rogers or any other relevant material, therefore giving the device an upper hand over other substrate accoutrement. The proposed antenna is configured to operate in the higher ISM band (5.725 GHz to 5.875 GHz) with an impedance bandwidth of 17.02%. Sorting pins and triangular slots on the patch surface have been introduced, which offer an ISM band, an excellent SAR value of 255.235 W/ Kg, a directive gain of -25.117 dB, and improving the performance of the suggested antenna. Using high frequency structure software (HFSS) tool, detailed analysis of the suggested implantable antenna has been carried out and thoroughly investigated for overall comparison and improvement., {"references":["1.\tNguyen, D., & Seo, C. (2021). An ultra-miniaturized antenna using loading circuit method for medical implant applications. IEEE Access, 9, 111890-111898.","2.\tLiu, C., Guo, Y. X., & Xiao, S. (2016, March). A review of implantable antennas for wireless biomedical devices. In Forum for electromagnetic research methods and application technologies (FERMAT) (Vol. 14, No. 3, pp. 1-11).","3.\tNehra, R. K., & Raghava, N. S. (2021, December). Enhanced Impedance Bandwidth of Highly Compact Implantable Antenna using Magnetodielectric Substrate. In 2021 International Conference on Industrial Electronics Research and Applications (ICIERA) (pp. 1-5). IEEE.","4.\tKhan, A., Alamry, K. A., & Asiri, A. M. (2021). Multifunctional Biopolymers‐Based Composite Materials for Biomedical Applications: A Systematic Review. ChemistrySelect, 6(2), 154-176.","5.\tSalim, M., & Pourziad, A. (2015). A novel reconfigurable spiral-shaped monopole antenna for biomedical applications. Progress In Electromagnetics Research Letters, 57, 79-84.","6.\tAndreuccetti, D. (2012). An Internet resource for the calculation of the dielectric properties of body tissues in the frequency range 10 Hz-100 GHz. http://niremf. ifac. cnr. it/tissprop/.","7.\tKirtonia, P., Hosain, M. K., & Rahman, T. (2018, December). Miniaturized and differentially fed implantable antenna for biomedical telemetry applications. In 2018 10th International Conference on Electrical and Computer Engineering (ICECE) (pp. 349-352). IEEE.","8.\tLiu, R., Zhang, K., Li, Z., Cui, W., Liang, W., Wang, M., ... & Li, E. (2021). A wideband circular polarization implantable antenna for health monitors microsystem. IEEE Antennas and Wireless Propagation Letters, 20(5), 848-852.","9.\tLiu, C., Guo, Y. X., & Xiao, S. (2014). Capacitively loaded circularly polarized implantable patch antenna for ISM band biomedical applications. IEEE transactions on antennas and propagation, 62(5), 2407-2417.","10.\tNehra, R. K., & Raghava, N. S. (2021, October). Highly compact triple ring slotted circular polarized implantable antenna for bio-medical applications. In 2021 6th International Conference on Signal Processing, Computing and Control (ISPCC) (pp. 186-190). IEEE."]}

Background / Aim: Clinical trials are becoming more popular in India, but its awareness among the medical professionals remains far from satisfactory. Clinical research/trial can help medical students in developing the critical thinking abilities necessary for medical practice. In this era of evidence-based medicine, the integration of medical education and clinical research is crucial to ensure that scientific findings are translated into clinical practice. The present study aimed to find out the awareness about clinical trial among undergraduates. Methods: After obtaining approval from the Institutional Ethics Committee, this cross-sectional study was conducted on students from first to final year and interns after taking their consent. A sample of 390 respondents was analysed. A structured questionnaire was used to measure the objective of this study. The proportion of successfully answered questions in each group was computed and the results were sorted into pre-determined grades as follows: As excellent - 80-100 %, moderate - 50-80 % and terrible - less than 50 %. Results: Out of 390 undergraduate students, for the statement regarding the concept of clinical trials, around 28.2 % fell in the good category, 57.7 % in the average category and 14.1 % in the poor category. Regarding the statement about role of the United States Food and Drug Administration (US FDA) in approving new drug, 34.1 % were poor responders, 52.6 % were average and 13.3 % were good. The statements regarding the participation in the clinical research study showed that majority were in the poor and average response category (45.6 % and 41.5 %, respectively) as compared to only 12.8 % in the good category. Conclusions: The overall awareness of clinical trials was low among students, the medical undergraduates are future innovators, clinicians and scientific explorers. It would be better if they are trained at earlier days of learning about clinical trials/research and medical ethics. These can be made a part of medical curriculum so that they can build their concrete future.

The paper focuses on the design, development, and evaluation of a gripper intended to hold hollow objects by interacting with the inner surface. The gripper moves towards the inside of the hollow object and grips it using the friction forces applied on the surface of the object. The design also ensures the application of variable normal forces on the surface of the object to be grasped. The mathematical architecture is verified using prototypes and experiments.

Citizen Science (CS) is gaining popularity among a section of the Indian Research Community as a potential cost-effective tool to generate and gather large-scale temporospatial-distributed research data with the help of non-scientist citizens ready to volunteer their free time for science and societal issues. However, CS activities in India seem confined to a few selected research disciplines at selected geolocations. This poses challenges and scope to incorporating CS into all Indian Higher Education Institutions (HEIs) as an experimental learning tool. We conducted a pan-India, online survey and assessed the scope and challenges of CS in Indian HEIs. The survey recorded the perception of all stockholders irrespective of their academic and professional background for four months, from January to May 2021. Survey results revealed explicit geographical and research discipline-wise biases in participants' acquaintance and preference for CS. Agriculture/Biodiversity/Ecology/Environment Science disciplines recorded around 67% of responses. More than two-thirds of respondents conveyed their interest in CS. However, they highlighted the lack of hand-on-experience and opportunity for formal training on CS at schools/university levels. The study emphasized the inclusion of the CS curriculum in the mainstream education system to train the next generation of researchers on several aspects of CS and tap its potential for large-scale research studies in all higher education disciplines.

The performance effect of splitting and abrupt doping in the drain region, use of a Ge strip at source-channel junction in group IV material based (Ge1 − xSnx/ Si1 − y − zGeySnz) Tunnel Field Effect Transistor (TFET) is investigated in the present manuscript. The variation of certain device parameters, such as mole fraction, different gate dielectrics, gate dielectric thickness and drain doping concentrations are applied to analyze the performance of proposed group IV material based TFET in terms of current-voltage (I-V) characteristics, potential profile and ION/IOFF ratio using device simulator SILVACO TCAD. The simulation results obtained for the proposed TFET structure are compared with the other TFET structures available in the literature, which shows better results as ION/IOFF ratio was received of the order of 1012 in comparison to conventional group IV material based TFET and subthreshold swing of 25.03 mV/decade, which makes the proposed structure promising for high speed switching action with low power CMOS compatibility.

Galactomannans are naturally occurring biocompatible and biodegradable nonionic polysaccharides comprised of mannose and galactose residues. They are under investigation for the design of various drug delivery carriers such as matrix tablets, microparticles, nanoparticles/nanocomposites, polymeric micelles, hydrogels, as well as pharmaceutical excipients. Amongst galactomannans, guar gum, locust bean gum, and fenugreek gum are the biomaterials mostly investigated for their potential utility as nanocarriers for various purposes, either in their native or modified forms. The galactomannan-based nanomaterials have been fabricated by adopting various strategies. These galactomannan nanomaterials have been tested for oral vaccination, oral insulin delivery, cancer cell & macrophage targeting, controlled drug delivery, heavy metal extraction and wound dressing applications. The galactomannan has attracted the attention of researchers as reducing agents for the green synthesis of metal nanoparticles as well. These nanometals have shown improved antimicrobial, antioxidant and anticancer activities. In vitro toxicity of the nanomaterials is also assessed in some instances. Others such as cassia gum, tara gum, Delonix, Leucaena leucocephala, Punica granatum galactomannans are amongst the least studied materials for biological applications. This review describes various strategies adopted for the synthesis of galactomannan-based nanomaterials, their properties and applications, especially in the field of drug delivery.

The current research presents a novel third-order nonlinear optical single crystal named diisopropylammonium succinate by slow evaporation solution growth technique. Single-crystal X-ray diffraction and nuclear magnetic resonance techniques are utilized to validate the synthesis and formation of the titled crystal. The grown crystal belongs to monoclinic crystal system with space group P21/n, and its lattice parameters are found to be a = 8.3660 A, b = 11.4818 A, c = 13.5239 A and β = 98.3810°. 1H NMR and 13C NMR revealed the hydrogen bonds present within the molecules of crystal. The 3D visualization of intermolecular interactions was understood by the color contour of Hirshfeld surface of the grown crystal. UV–Vis and photoluminescence spectroscopic techniques are employed to understand the linear optical behavior of the reported crystal. The thermal stability of the material is facilitated by thermogravimetric analysis and differential thermal analysis. The titled crystal is found to be stable up to 140 °C. The third-order nonlinear optical behavior is determined using the z-scan technique.

Background: Bone marrow edema is assumed to be caused as a result of trabecular microfractures that are detected by MRI. As MRI is not widely available in countries like India, this study aims to encourage the use of DECT in detection of bone edema as evidence with comparable efficiency to MRI. Aim: To assess the diagnostic accuracy of dual-energy CT in detecting bone marrow edema in patients of trauma of lower limb and correlate it with MRI. Setting and Design: It is a cross-sectional study. Materials and Methods: The study included 40 patients of age 15–70 years irrespective of sex. All the patients of lower extremity trauma underwent DECT and MRI evaluation after clinical evaluation. All the images were postprocessed on a work station and were further evaluated by a radiologist. Results: Mean attenuation at fractured site observed by Dual energy CT was found to be significantly higher as compared to that at adjacent site (170.75 ± 33.99 vs. 19.73 ± 22.50 HU). The sensitivity and specificity of dual energy CT as compared to MRI in detecting bone marrow edema were 94.1% and 91.3%, respectively. Of the 40 cases enrolled in the study, agreement of MRI and Dual energy CT was observed in 37 (92.5%). Conclusion: Dual energy CT can be an effective alternative to MRI in the detection of bone marrow edema in patients of lower limb trauma. Dual energy CT can also be used in patients in whom MRI is contraindicated.

Single crystals of pure and xylenol orange (XO; C31H32N2O13S) dye doped (0.01, 0.05 and 0.1 mol%) ammonium dihydrogen phosphate (ADP; NH4H2PO4) were grown by slow evaporation method with the vision to improve the properties of pure ammonium dihydrogen phosphate crystal. The theoretical morphology of the grown crystals was drawn using Bravais–Friedel–Donnay–Harker (BFDH) law. The selective nature of xylenol orange dye to selectively stain the particular growth sectors of ADP crystal was studied. The structural analysis of as grown crystals was carried out using powder XRD study. The identification of the functional groups present in the ADP material was done using Fourier transform infrared (FTIR) spectroscopy. The linear optical study on pure and dye doped crystals was carried out using UV–vis–NIR spectroscopy. The optical band gap, extinction coefficient, refractive index and optical conductivity were calculated using the transmittance spectra for all the samples. In photoluminescence studies, the blue emission intensity got quenched and an orange emission at 597 nm was seen as a result of XO doping. The thermal stability and decomposition temperature of ADP crystal were found to decrease as an effect of dye doping. The piezoelectric charge coefficient, SHG conversion efficiency, mechanical strength and wettability were also enhanced as a result of XO dye doping. Keywords: Nonlinear optical materials, Dye-doped crystals, Optical properties, Piezoelectricity, Mechanical properties

COVID-19 has acted as a roadblock to mental health services across the globe, and the isolation because of the lockdowns has caused various depressive problems. Through this paper, we aim to determine the effect of COVID-19 on the public's mental health. Data obtained from some specific subreddits helps us identify a pool of users whose mental condition was affected by the pandemic. Using transformer-based classification models on the selected users' Reddit activity, we found 6.4% of our user base to be free from any mental issues before the pandemic. Further experiments show that most of the users posted about their struggles due to the pandemic during the March-May period.

A near morphotropic phase boundary composition of a new quaternary ceramic 0.47(Bi0.5Na0.5)TiO3–0.04BaTiO3–0.31Pb(Mg1/3Nb2/3)O3–0.18PbTiO3 [BNT–BT–PMN–PT] has been synthesized using the solid state reaction method. The ceramics were characterized for their ferroelectric properties along with dielectric and piezoelectric characteristics. High value of maximum dielectric permittivity (~ 4140) and transition temperature (Tc ~ 190 °C) with low dielectric loss (

In the present technologically advanced era, non-linear optical materials especially organic derivatives are in the limelight due to their fast response in electro-optic switches and high nonlinear efficiency. Therefore, with respect to this behaviour, single crystals of L-argininium Bis(trifluoroacetate) (here in after called LABTF) an organic material was grown by slow evaporation solution growth technique. The grown single crystal was subjected to single crystal X-Ray diffractometer to validate its chemical structure and compound formation. The titled compound crystallizes into an asymmetric entity that comprises of one divalent L-argininium cation and two monovalent trifluoroacetic anion. All the intermolecular hydrogen bonds present in the LABTF crystal structure are investigated by 3D molecular Hirshfeld surface analysis and their relative involvements are disintegrated using 2D fingerprint plots. Further, the crystalline perfection assessment was performed using high-resolution X-Ray diffractometer which divulges the absence of structural grain boundaries in the obtained crystal. Thermal transport parameters of the titled compound were measured through Photoacoustic spectroscopy. The shock strength above which the crystal induces damage was found by the shock damage threshold technique. In addition, mechanical property related parameters such as hardness, stiffness and Young's Modulus were evaluated using the nanoindentation technique. These mechanical parameters resolve the reliability of devices and it can be enhanced by improving the crystal quality.

From ancient times, minerals have been recognized by their distinct external shapes. Very recently, there is a growing interest towards shape control of nanocrystals and microcrystals as various properties like optical, electrical and magnetic are greatly influenced by their external shape. ZnO nanocrystals find various applications in physics, optics, medicine, and electronics. Predicting equilibrium shape of ZnO nanocrystals is an important step to judge their capability in different uses for instance in drug delivery or energy storage. However, predicting morphology for ZnO nanocrystals is tedious, because ZnO crystalline material grows with a diverse range of external shapes. In present report, external morphology of ZnO crystal is deduced from its internal crystal structure by considering the propagation vector of center of mass of the molecular basis (namely HNB vector; Harsh−Nidhi−Binay) in the ZnO lattice. Also, two of the well established models namely Bravais−Friedel−Donnay−Harker model (BFDH), and Hartman−Perdok (HP) periodic-bound chain (PBC) vectors model were used to predict morphology of ZnO crystal. The results of all the three models are compared against the experimentally observed morphologies of ZnO nanoparticles by various research groups. Results suggest that the morphology predicted by BFDH law, HP theory and HNB theory completely agrees with the actual grown ZnO crystal shape by different research groups as well as proves the diversity in the external shape of ZnO nanocrystals.

The COVID-19 pandemic was greatest crisis humankind has witnessed in recent past. This crisis has forced the government across the world to in force lockdown. The Indian government followed the same step and took hardest decision of lockdown in whole India. All economic activities was stopped.In this work, the effect of lockdown on the usages of energy and its pattern is analyzed for Indian. This potential shift in energy usage and supply has generated different scenarios, which can be effectively utilized and can provides a key input to policymakers and stakeholders to cope up further on pollution is also analyzed for the same period.

In the era of smart city, developing environmental decision support system (EDSS) integrated with monitoring, modelling, planning and control for smart management of urban river water quality has been widely accepted and implemented around the world. Construction and coupling localized water quality models, such as popular WASP and EFDC by USEPA, to meet different management requirements are fundamental for the surface water EDSS development. However, few reported the technique coupling the advanced version of WASP program with EDSS platform. Traditional pathway of EDSS integrations or model coupling, e.g. database-oriented interaction, are non-modular, with low efficiency of share and reuse, and difficult for system updating. With the development of cloud computing and web services, the service-oriented design are the future trends of model coupling.In this paper, a generic interface/module interacting with WASP V7.5 program is developed and the technical route of tightly coupling is proposed. The web service encapsulation of localized WASP models and advanced cloud computing services are implemented with the help of OpenGMS framework and SaaS (software as services) pattern. To meet the basic requirements of urban water quality management, the water assimilative capacity allocation and pollution load reduction planning are work out by the cloud computing services, which achieves operational running of EDSS.The study area is located in Maozhou River Basin, an urban river in Shenzhen, China. According to the national water environment code and regulations, COD (chemical oxygen demand) and NH3-N (ammonia nitrogen) are set as the ending point for supervision and the corresponding WASP model of Maozhou River is constructed and calibrated by historical field data. The computing components and web-services are integrated into the comprehensive water quality management platform of Maozhou River through the model configuration and controlling data parameterization. One version of the Maozhou River EDSS has been deployed and is online on the Shenzhen ecological and environmental intelligent management and control center since January, 2021.Along with WASP, service-oriented encapsulating of EFDC and SWMM based computing components for particular management purposes are also implemented based on the same technique route since both of them are developed by USEPA with similar inputs and outputs. The technology of model coupling and platform integration mentioned in this paper provides a valuable paradigm for linking other environment models into specific management business. Under the proposed technical pathway, the interaction of model interface between computation engine and system business layer can be easily updated along with the changes of management requirements. It provides the merits of rapidly development, easily deployment and maintenance.

Normal lungs can be distressed by internal as well as external factors which can be reason for producing diseases. The lungs respond against these factors via a protective mechanism known as inflammation. Cytokines, small secreted proteins, play a crucial role to control these inflammations, but overproductions of cytokines create many respiratory diseases (responsible for high mortality rates). These types of respiratory diseases are treated with the help of anti-inflammatory agents to minimize the pulmonary inflammation. Medicinal plants and drugs derived from plants have numerous therapeutic effects when utilized by patients. Occurrence of several active phytoconstituents in plants is useful to treat many types of inflammatory diseases. The use of medicinal plants and phytoconstituents (alkaloids, flavonoids, terpenes, and others) as curative tool in pulmonary inflammation is increasing significantly. In the current book chapter, the role of medicinal plants and phytoconstituents for the managing pathophysiology of lung diseases is appraised.

Recently, blockchain technology has been recognized for other industries than finance, proving it's potential other than cryptocurrencies and bitcoin. Supply chain is one of the exponentially growing industries which needs to undergo through changes in order to survive in tomorrow's economy. There are many risks involved in current supply chains that can be potentially eliminated with the implementation of blockchain. This chapter analyses the various aspects of blockchain technology and how other technologies can be integrated with it to deliver exceptional solutions. Various risks present in the current system are discussed along with how those risks can be handled using blockchain, contributing towards building a risk resilient supply chain.

Introduction: Enteric fever is the major health problem of developing country like India, with a notable morbidity and mortality. Isolation of Salmonella the causative agent from Blood is the standard laboratory method for diagnosis, but it is not available at PHC level. So, rapid and affordable diagnostic test like Widal tube and slide agglutination test are used. The present study was done to comparatively evaluate the Widal slide agglutination and tube agglutination test in detecting enteric fever. Methods: A total of 500 patients with clinical presentation suggestive of enteric fever were included in the study whose venous blood was collected. All the samples were tested for the presence of anti O and anti H agglutinins against S. typhi and S. paratyphi A by semi quantitative slide and quantitative tube agglutination tests as per standard protocols. The titers of 1:80 (O agglutinins) and 1:160 (H agglutinins) were taken as the significant titer for the diagnosis of enteric fever. Results: Out of 500 collected samples, 183 (36.6%) was positive by slide agglutination test, whereas, only 145 (29%) were positive by tube agglutination method. The slide test had a sensitivity of 97.2%, specificity of 88.1%, positive predictive value of 77% and negative predictive value of 98.7% as compared to Widal tube agglutination test. Conclusions: Due to high false positivity shown by slide test, it is suggested that serological diagnosis should not be made solely on the basis of slide test rather its results should be confirmed by using Widal tube agglutination test. Keywords: Enteric fever, Slide agglutination test, Widal tube agglutination test, Sensitivity, Specificity

In this paper, a 1-bit full adder is implemented using the Gate-Diffusion-Input (GDI) technique and its design analysis is carried out. The design parameters such as delay, power consumption, energy delay product, energy and transistor count are compared with the conventional static CMOS based design. The effect of parasitic capacitance is analyzed via post layout simulation. This reveals that the delay and power consumption of the GDI adder is around 19% and 94% less than to that of CMOS based approach along with reduced number of transistor count.

The start of the space race between the two cold war rivals United states and the Soviet Union in the 20th Century added a new dimension to both law as well as science. The frontier of space research and discoveries intertwined the connection between law and science. However, just like science being an important aspect of human evolution so is the regulation of such activities through the hands of law, as one can use and abuse these aspects. One key notion of space exploration and how far we have come since we first landed on the moon brings forth the question of commercialization of space through private means such as space tourism as it is a big step towards fulfillment of human dreams to be independent from our home planet. There are several aspects which need to be brought in light in terms of legal issues that seek solution in relation to regulation of commercial activities in space. The legal issues pertain to the regulation of aerospace vehicles used by private or public entities for commercial purposes and also require a legal framework for entrepreneurs and private organization in order to promote and develop such a sector of commercial activity. It needs to be analyzed in order to see the effect of existing laws as well as provide a base for other interested entities to enter such a domain. There is another legal aspect which needs to be taken a closer look at and that is of liability aspect commercial activities in space. The current study analyzes the legal aspect of commercial space activities and the basis of liability issues involved in conducting these activities such as space tourism.

Pure and Neodymium (Nd) doped ZnO nanorods were prepared using cost effective wet chemical co-precipitation method and used for the fabrication of flexible piezoelectric nanogenerator. The structure and morphology of ZnO and Nd-ZnO samples were studied using powder X-ray diffraction, FESEM and TEM techniques. Ferroelectric measurements showed a remanent polarization (Pr) of ∼0.064 μC/cm2 and coercive field (Ec) of ∼6.04 kV/cm, respectively at 600 V. Leakage current density was found to be reduced after Nd doping in ZnO nanorods. Enhanced Curie temperature (Tc = 125 °C) and large piezoelectric coefficient (d33 = 512 pm/V) were observed in Nd doped ZnO nanorods, which makes Nd-ZnO a better candidate for piezoelectric energy harvesting and high temperature nano-storage devices. Moreover, flexible piezoelectric nanogenerators (PENGs) were fabricated using ZnO and Nd-ZnO nanorods. The Nd-doped ZnO based NG showed high piezoelectric performance by generating average voltage of ∼31 V under finger tapping (∼0.3 N), which was more pronounced in comparison to ZnO based NG (∼2 V).

Cocrystals of glycine glutaric acid (GGA) were grown by slow evaporation solution technique. The crystal structure and the lattice parameters of GGA cocrystal were determined by using powder XRD analysis. UV-vis-NIR spectrum showed that GGA cocrystal is highly transparent in visible and near infrared region with a wide-band gap 5.27eV. The photoluminescence spectrum showed two peaks: one of high intensity at wavelength 410 nm and another of much lower intensity at 355 nm. Dielectric properties of GGA cocrystal were measured across three different crystallographic planes namely (010), (011) and (110). The relative SHG conversion efficiency of GGA was found to be 0.35 times that of KDP crystal. Mechanical stability of (010) plane of GGA cocrystal was analyzed using nanoindentation technique and various parameters like hardness, Young's modulus and stiffness were estimated. Thus, GGA is a potential candidate for multifunctional NLO and optoelectronic devices.

Ferroelectricity in pure ZnO nanocrystals is an unlikely physical phenomenon. Here, we show origin of high temperature ferroelectricity in ZnO as a result of yttrium (Y) doping. First, we briefly introduced the wet chemical synthesis of pure and yttrium (Y) doped ZnO nanocrystals. The crystalline phase and morphological appearance of as synthesized pure and Y-doped ZnO nanocrystals were examined using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. By Y-doing, the morphology of ZnO crystals evolved from 1D nanopencil (pure ZnO) to 3D flower-like architectures assembled by 2D porous nanosheets (Y-ZnO). Crystallite size, deformation stress, energy density and lattice strain of both the nanoparticles were evaluated using Scherrer and Williamson-Hall methods. Frequency as well as temperature dependence of dielectric constant, dielectric loss and ac conductivity of Y-doped ZnO nanosheets were investigated. Ferroelectricity in Y-doped ZnO nanosheets was established using the temperature dependent curve of dielectric constant and the room temperature polarization hysteresis loop. The temperature dependent curve of dielectric constant displayed a ferroelectric to paraelectric transition peak at 138 °C. The Y-ZnO nanosheets exhibit weak ferroelectric polarization hysteresis loop with a remnant polarization (Pr) of 0.09 µC/cm2 and a coercive field (Ec) of 5.87 kV/cm (@ RT). The nature of the leakage present in Y-ZnO sample was extracted from the time-dependent compensasted (TDC) hysteresis study. Leakage current density was found to decrease due to Y-doping in ZnO nanocrystals.

Single crystals of pure and sunset yellow (SSY) dye doped (0.05 mol%) triglycine sulphate (TGS) were grown by slow evaporation solution technique with the vision to improve the properties of pure TGS crystal. The external morphology of TGS crystal was deduced from its internal crystal structure by using two of the well established models, namely Bravais–Friedel–Donnay–Harker model (B–F–D–H) and Hartman–Perdok (H–P) periodic-bound chain (PBC) vectors model. The selective nature of sunset yellow dye to selectively stain the particular growth sectors of TGS crystal was studied. The structural analysis of both the crystals was carried out using powder XRD and FTIR studies. UV–Vis–NIR spectroscopy was carried out on both pure and SSY dyed TGS crystals to study their linear optical properties and various optical parameters namely optical band gap, refractive index, extinction coefficient and optical conductivity were determined. The thermal stability, melting point, ferro- to para-electric transition temperature, piezoelectric charge coefficient, ferroelectricity and mechanical hardness got enhanced as an effect of SSY dye doping in TGS matrix. The piezoelectric conversion efficiency (d22) got enhanced from ~ 56 pm/V for pure TGS single crystal to ~ 85 pm/V for SSY doped TGS single crystal. The true-remanent polarization was determined for dyed TGS crystal using ‘Remanent Hysteresis Task’ which showed the presence of very small contributions of non-switchable components. ‘Time-Dependent Compensated (TDC)’ hysteresis task revealed the absence of resistive leakage in SSY-Doped TGS crystal. The pyroelectric coefficient got enhanced from ~ 761 µCm−2/°C for pure TGS single crystal to ~ 850 µCm−2/°C for SSY doped TGS single crystal. Comparative optical, mechanical, dielectric, piezoelectric, ferroelectric and pyroelectric studies provide useful scientific information of an important class of TGS crystals and suggest SSY-Doped TGS crystal as a better alternative than pure TGS crystal for various opto-electronics and ferroelectric devices applications.