Reaction of wood with inorganic salts

Wood samples and veneers of Hevea brasiliensis (Rubber wood) and Acacia auriculaeformis treated with aqueous solutions of chromium trioxide, ferric chloride and ferric nitrate were studied for water repellency and their reaction with wood constituents. FTIR spectra obtained from wood surface treated with chromium trioxide indicate the formation of a water insoluble complex between chromium trioxide and aromatic ring of lignin, whereas no reaction takes place with ferric salts. Treatment of wood by chromium trioxide was found to be effective in imparting water repellency in wood.     

Optical and structural properties of electrodeposited polyaniline/Q‐CdS composites

HCl doped polyaniline (PANI)/Q‐CdS composite thin films have been synthesized using the electrodeposition route on indium tin oxide (ITO) coated glass substrates. Three different sizes of CdS quantum dots were uniformly dispersed in PANI matrix. As deposited samples were characterized by X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). Optical properties of the composite structures were investigated by using optical absorption, photoluminescence, and Raman spectroscopy. PANI/Q‐CdS composite showed significant improvement in the thermal behavior as indicated by thermogravimetric analysis (TGA) thermograph. Our results also indicated that the doping state of the nanocomposites was dependent on the size of the CdS nanoparticles and improved with decreasing size. POLYM. COMPOS., 35:1864–1874, 2014. © 2014 Society of Plastics Engineers     

Identification of FOPDT and SOPDT process dynamics using closed loop test

In this paper, identification of stable and unstable first order, second order overdamped and underdamped process dynamics with time delay is presented. Relay with hysteresis is used to induce a limit cycle output and using this information, unknown process model parameters are estimated. State space based generalized analytical expressions are derived to achieve accurate results. To show the performance of the proposed method expressions are also derived for systems with a zero. In real time systems, measurement noise is an important issue during identification of process dynamics. A relay with hysteresis reduces the effect of measurement noise, in addition a new multiloop control strategy is proposed to recover the original limit cycle. Simulation results are included to validate the effectiveness of the proposed method.     

Effect of Ultrasonic Shot Peening on Microstructure and Mechanical Properties of High-Nitrogen Austenitic Stainless Steel

The effect of ultrasonic shot peening (USSP) was studied on microstructural modification and mechanical properties such as microhardness, yield strength, tensile strength, and low cycle fatigue (LCF) life of a nitrogen stabilized austenitic stainless steel, at room temperature. There was grain refinement up to nano scale in surface region of the shot peened specimens and the microhardness was increased markedly up to the depth of approximately 100 µm. There was insignificant increase in yield and tensile strength, but drastic reduction in LCF life, particularly at low strain amplitude, from USSP. The nominal increase in yield and tensile strength was due to grain refinement in the surface region and drastic fall in LCF life was due to surface cracking resulting from USSP.     

Diamond like carbon coatings deposited by microwave plasma CVD: XPS and ellipsometric studies

Diamond-like carbon (DLC) films were deposited by microwave assisted chemical vapour deposition system using d.c. bias voltage ranging from −100 V to −300 V. These films were characterized by X-ray photoelectron spectroscopy (XPS) and spectroscopic ellipsometry techniques for estimating sp ³/sp ² ratio. The sp ³/sp ² ratio obtained by XPS is found to have an opposite trend to that obtained by spectroscopic ellipsometry. These results are explained using sub-plantation picture of DLC growth. Our results clearly indicate that the film is composed of two different layers, having entirely different properties in terms of void percentage and sp ³/sp ² ratio. The upper layer is relatively thinner as compared to the bottom layer.     

Effect of impinging ion energy on the substrates during deposition of SiOx films by radiofrequency plasma enhanced chemical vapor deposition process

Radiofrequency (13.56 MHz) plasma enhanced chemical vapor deposition process is used for deposition of SiO_x films on bell metal substrates using Ar/hexamethyldisiloxane/O₂ glow discharge. The DC self-bias voltage developed on the substrates is observed to be varied from − 35 V to − 115 V depending on the RF power applied to the plasma. Plasma potential measurements during film deposition process are carried out by self-compensated emissive probe. The deposited films are characterized by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), nanoindentation, nano-scratch test and thermogravimetric analysis. The characterization results show strong dependency of the SiO_x films properties on the energy of the ions impinging on the substrates during deposition. Analysis of Raman spectra indicates an increase in vitreous silica content and reduction in defective Si-O-Si chemical structure in the deposited SiO_x films with increasing ion energy impinging on the substrates. The increase in inorganic (Si and O) content in the SiO_x films is further confirmed from XPS analysis. The growth of SiO_x films with more inorganic content and defect free chemical structure apparently contribute to the increase in their hardness and scratch resistance behavior. The films show higher thermal stability as the energy of the ions arriving at substrates increases with DC self-bias voltage. The possibility of using SiO_x films for surface protection of bell metal is also explored.     

Geospatial technology applied to spatiotemporal assessment of Harike Wetland,Punjab

The Harike Wetland situated in Punjab is a Ramsar site and a wetland of national importance. The present study was undertaken to assess the spatiotemporal dynamics of the wetland on the basis of geospatial technology and ground‐based studies. Landsat images for the years 2002 and 2014 were acquired from the United States Geological Survey and classified digitally to generate landuse/land cover maps involving four classes (water, grassland (including water hyacinth), agriculture, built‐up (settlement), barren land). The total area of the Harike Wetland was found to be 8023.68 ha. Water sampling at eleven sites was carried out and evaluated for physicochemical parameters. The water quality at several sampling points was found to be severely degraded. Change detection analysis revealed the submerged area (area under water) and grassland (including water hyacinth) had decreased over the past 12 years, whereas that area under agriculture and built‐up land has increased, indicating a shrinkage in the total wetland area. The present study also indicated that the near‐infrared band is a good indicator of water quality parameters, as indicated by the significant positive correlation between the near‐infrared band and relevant water parameters. Because the wetland is important from both an ecological perspective and economic perspective, regular monitoring is recommended, for which geospatial technology has proven to be very useful.     

Rightful ownership through image adaptive DWT-SVD watermarking algorithm and perceptual tweaking

In this paper, a tailored blended image adaptive watermarking scheme has been presented, which is based on DWT and SVD. Through this paper an attempt has been made to solve the problem of false positive while maintaining the robustness and imperceptibility with the help of principal component and perceptual tuning of the image. Perceptual tuning is a non-blind technique and based on the objective quality of image. The embedding strength is made dependent on watermark features as well as of host in wavelet domain by using tuning parameter which is user specific. The idea of embedding the principal component of intermediate frequency sub-bands of watermark image into singular values of perceptually tuned intermediate frequency sub-bands of host image have been exploited. The proposed algorithm is providing the adaptive behavior towards the image content for perceptual transparency and at the same time avoiding the possibility of false watermark extraction well supported by a private key, which is necessary at the time of extraction. Thus the proposed watermarking algorithm is a kind of non-blind, image adaptive and suitable for rightful ownership. Various comparative results make the algorithm superior in terms of intentional and non-intentional attacks. Also the algorithm is strong against the print and scan attack.     

COVIDScreen: explainable deep learning framework for differential diagnosis of COVID-19 using chest X-rays

Neural Computing and Applications - COVID-19 has emerged as a global crisis with unprecedented socio-economic challenges, jeopardizing our lives and livelihoods for years to come. The...     

Identification of critical erosion prone areas in the small agricultural watershed using USLE,GIS and remote sensing

In the present study, Karso watershed of Hazaribagh, Jharkhand State, India was divided into 200 × 200 grid cells and average annual sediment yields were estimated for each grid cell of the watershed to identify the critical erosion prone areas of watershed for prioritization purpose. Average annual sediment yield data on grid basis was estimated using Universal Soil Loss Equation (USLE). In general, a major limitation in the use of hydrological models has been their inability to handle the large amounts of input data that describe the heterogeneity of the natural system. Remote sensing (RS) technology provides the vital spatial and temporal information on some of these parameters. A recent and emerging technology represented by Geographic Information System (GIS) was used as the tool to generate, manipulate and spatially organize disparate data for sediment yield modeling. Thus, the Arc Info 7.2 GIS software and RS (ERDAS IMAGINE 8.4 image processing software) provided spatial input data to the erosion model, while the USLE was used to predict the spatial distribution of the sediment yield on grid basis. The deviation of estimated sediment yield from the observed values in the range of 1.37 to 13.85 percent indicates accurate estimation of sediment yield from the watershed.