Growth and properties of lead iodide thin films by spin coating

In this study, lead iodide (PbI2) thin films were deposited on glass substrates by spin coating a solution of 0.2 M PbI2 dissolved in dimethylformamide, varying the deposition time and the spin speed. The thickness of the thin films decreased with increase in spin speed and deposition time, as examined by profilometry measurements. The structure, morphology, optical and electrical properties of the thin films were analysed using various techniques. X-ray diffraction patterns revealed that the thin films possessed hexagonal structures. The thin films were grown highly oriented to [001] direction of the hexagonal lattice. Raman peaks detected at 96 and 136 cm−1 were corresponding to the characteristic vibration modes of PbI2. The X-ray photoelectron spectroscopy detected the presence of Pb and I with core level binding energies corresponding to that in PbI2. Atomic force microcopy showed smooth and compact morphology of the thin films. From UV–Vis transmittance and reflectance spectral analysis, the bandgap of the thin films ∼2.3 eV was evaluated. The dark conductivity of the thin films was computed and the value decreased as the deposition time and spin speed increase

Copper antimony sulfide thin films for visible to near infrared photodetector applications

Ternary chalcostibite copper antimony sulfide (CuSbS(2)) is an emerging semiconductor material having applications in photovoltaics, energy storage and optoelectronics due to its high absorption coefficient, suitable bandgap, and it consists of non-toxic and earth abundant elements. CuSbS(2) thin films are prepared by combining chemical bath deposition (antimony sulfide (Sb(2)S(3))) and thermal evaporation (copper (Cu)) followed by a heat treatment and their application as visible to near infrared photodetectors is reported. Crystalline structure, elemental composition, chemical state, morphology and optoelectronic properties of the films were characterized by various techniques. The effect of three different Cu thicknesses (CAS 20, CAS 30 and CAS 40 nm) on the photodetection properties are evaluated under illumination using light emitting diodes (LEDs) and a laser. The photodetectors fabricated are successfully tested under different wavelengths, power densities and applied voltage and their photoresponse cyclic stability for each wavelength of illumination was recorded. From the sensitivity calculations, the sample with 20 nm Cu thickness (CAS 20) showed higher detection sensitivity for visible to near infrared wavelengths. Better responsivity results were obtained for CAS 40 because of its improved crystallinity and phase purity. Photodetector properties such as sensitivity and responsivity are evaluated for all the samples. These results are beneficial for cost effective and environment friendly photodetectors and optoelectronic devices based on CuSbS(2) thin films

A characteristic study of humic acids isolated from Arctic fjord sediments

Humic substances are ubiquitous natural materials found in sediments as a product of biochemical transformation reactions representing a significant proportion of organic carbon cycle on earth. This study involves the analysis of humic substances with special emphasis on humic acids (HAs) in sediments collected from the Kongsfjorden System of Arctic region in June, 2017. The characterization of the isolated HAs were done using various spectroscopic techniques viz. UV-visible, Fluorescence, FTIR and NMR. Isolated HAs were also undergone for elemental analysis along with other characterization. The UV spectral analysis results with a lower E4/E6 ratio suggesting the presence of HAs with high degree of aromaticity and condensation. Indications for the presence of hydroxyl, methyl, methylene, carbonyl, carboxyl, phenol, alcohol and amide groups were obtained from the FTIR spectrums of HAs. NMR spectral characteristics also confirm the presence of OH group as well as the presence of CH protons adjacent to C=X, were X can be any electronegative element. This also confirms the presence of carbonyl group which is also evident in the FTIR spectral studies. Presence of aliphatic regions slightly more dominated with long chain and/or alicyclic moieties rather than methyl groups was also inferred from the results of NMR

Synthesis and Properties of Platinum Nanoparticles by Pulsed Laser Ablation in Liquid

Platinum (Pt) nanoparticles were synthesized by pulsed laser ablation in liquid (PLAL) technique in different liquids (acetone, ethanol, and methanol). Ablation was performed using a Q-switched Nd:YAG laser with output energy of 230 mJ/pulse for 532 nm wavelength. Ablation time and laser energy fluence were varied for all the liquids. Effects of laser energy fluence, ablation time, and nature of the liquid were reported. The mean size, size distributions, shape, elemental composition, and optical properties of Pt nanoparticles synthesized by PLAL were examined by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV-Visible absorption spectroscopy

Post-Transplant Outcomes in High-Risk Compared with Non-High-Risk Multiple Myeloma: A CIBMTR Analysis.

Conventional cytogenetics and interphase fluorescence in situ hybridization (FISH) identify high-risk multiple myeloma (HRM) populations characterized by poor outcomes. We analyzed these differences among HRM versus non-HRM populations after upfront autologous hematopoietic cell transplantation (autoHCT). Between 2008 and 2012, 715 patients with multiple myeloma identified by FISH and/or cytogenetic data with upfront autoHCT were identified in the Center for International Blood and Marrow Transplant Research database. HRM was defined as del17p, t(4;14), t(14;16), hypodiploidy (-Y) or chromosome 1 p and 1q abnormalities; all others were non-HRM. Among 125 HRM patients (17.5%), induction with bortezomib and immunomodulatory agents (imids) was higher compared with non-HRM (56% versus 43%, P \u3c .001) with similar pretransplant complete response (CR) rates (14% versus 16%, P .1). At day 100 post-transplant, at least a very good partial response was 59% in HRM and 61% in non-HRM (P = .6). More HRM patients received post-transplant therapy with bortezomib and imids (26% versus 12%, P = .004). Three-year post-transplant progression-free (PFS) and overall survival (OS) rates in HRM versus non-HRM were 37% versus 49% (P \u3c .001) and 72% versus 85% (P \u3c .001), respectively. At 3 years, PFS for HRM patients with and without post-transplant therapy was 46% (95% confidence interval [CI], 33 to 59) versus 14% (95% CI, 4 to 29) and in non-HRM patients with and without post-transplant therapy 55% (95% CI, 49 to 62) versus 39% (95% CI, 32 to 47); rates of OS for HRM patients with and without post-transplant therapy were 81% (95% CI, 70 to 90) versus 48% (95% CI, 30 to 65) compared with 88% (95% CI, 84 to 92) and 79% (95% CI, 73 to 85) in non-HRM patients with and without post-transplant therapy, respectively. Among patients receiving post-transplant therapy, there was no difference in OS between HRM and non-HRM (P = .08). In addition to HRM, higher stage, less than a CR pretransplant, lack of post-transplant therapy, and African American race were associated with worse OS. In conclusion, we show HRM patients achieve similar day 100 post-transplant responses compared with non-HRM patients, but these responses are not sustained. Post-transplant therapy appeared to improve the poor outcomes of HRM

Health ans safety related to products used in painting, drawing and printmaking

Daily experience with product designers, test and diagnosis engineers it is realized that the depth of interaction among them, ought to be high for successful diagnosis of analogue circuits. With this knowledge in mind, a responsibility was undertaken to choose a popular diagnostic method and define a systematic procedure that binds together the knowledge of a product from a design, test and diagnostic engineer. A set of software utilities was developed that assists in automating these procedures and in collecting appropriate data for effective diagnosis of analogue circuits. This paper will discuss the chosen methodology for diagnosis and the associated procedures for block-level diagnosis of analogue electronic circuits in detail. The paper is concluded with an illustration of the methodology and the related procedures of an industrial automotive voltage regulator circuit as a representative example

A Robust Metric for Screening Outliers from Analogue Product Manufacturing Tests Responses

Mahalanobis distance is one of the commonly used multivariate metrics for finely segregating defective devices from non-defective ones. An associated problem with this approach is the estimation of a robust mean and a covariance matrix. In the absence of such robust estimates, especially in the presence of outliers to test-response measurements, and only a sub-sample from the population is available, the distance metric becomes unreliable. To circumvent this problem, multiple Mahalanobis distances are calculated from selected sets of test-response measurements. They are then suitably formulated to derive a metric that has a reduced variance and robust to shifts or deviations in measurements. In this paper, such a formulation is proposed to qualitatively screen product outliers and quantitatively measure the reliability of the non-defective ones. The application of method is exemplified over a test set of an industrial automobile product

Multivariate Model for Test Response Analysis

A systematic approach to construct an effective multivariate test response model for capturing manufacturing defects in electronic products is described. The effectiveness of the model is demonstrated by its capability in reducing the number of test-points, while achieving the maximal coverage attainable by the specific test method on an industrial circuit