Copper undercoats on the corrosion resistance of bright nickel-chromium and of nickel-iron-chromium electrodeposits on steel substrates

The present paper deals with the testing of the newly developed nickel-iron plating process with regard to the corrosion performance of coatings produced. Aceticacid saltspray method he6 been used as the test method.The results show that mild steel plated with nickel iron-chromium systems with iron contents up to 35 %are suitable for indoor applications though slightly inferior to nickelchromium systems. Uterature reports suggest that nickelchromium systems for outdoor applications are to be modified by inducing microporosity in the chromium top layer and by giving suitable undercoats. The use of a microporous chromium topcoat in improving the performance of nickel and nickel iron coatings are tested. The effect of copper undercoats on the corrosion performance of nickel and nickel iron-chromium systems are compared and it is concluded that a copper undercoat is more beneficial for a nickel ironchromium system than a ni~ekhromium system

Mask-less lithography for fabrication of optical waveguides

A flexible method for fabricating shallow optical waveguides by using femtosecond laser writing of patterns on a metal coated glass substrate followed by ion-exchange is described. This overcomes the drawbacks of low index contrast and high induced stress in waveguides directly written using low-repetition rate ultrafast laser systems. When compared to conventional lithography, the technique is simpler and has advantages in terms of flexibility in the types of structures which can be fabricated

Gene-gene Interaction Analyses for Atrial Fibrillation

Atrial fibrillation (AF) is a heritable disease that affects more than thirty million individuals worldwide. Extensive efforts have been devoted to the study of genetic determinants of AF. The objective of our study is to examine the effect of gene-gene interaction on AF susceptibility. We performed a large-scale association analysis of gene-gene interactions with AF in 8,173 AF cases, and 65,237 AF-free referents collected from 15 studies for discovery. We examined putative interactions between genome-wide SNPs and 17 known AF-related SNPs. The top interactions were then tested for association in a

Mendelian randomization supports bidirectional causality between telomere length and clonal hematopoiesis of indeterminate potential

Human genetic studies support an inverse causal relationship between leukocyte telomere length (LTL) and coronary artery disease (CAD), but directionally mixed effects for LTL and diverse malignancies. Clonal hematopoiesis of indeterminate potential (CHIP), characterized by expansion of hematopoietic cells bearing leukemogenic mutations, predisposes both hematologic malignancy and CAD. TERT (which encodes telomerase reverse transcriptase) is the most significantly associated germline locus for CHIP in genome-wide association studies. Here, we investigated the relationship between CHIP, LTL, and CAD in the Trans-Omics for Precision Medicine (TOPMed) program (n = 63,302) and UK Biobank (n = 47,080). Bidirectional Mendelian randomization studies were consistent with longer genetically imputed LTL increasing propensity to develop CHIP, but CHIP then, in turn, hastens to shorten measured LTL (mLTL). We also demonstrated evidence of modest mediation between CHIP and CAD by mLTL. Our data promote an understanding of potential causal relationships across CHIP and LTL toward prevention of CAD

Current efficiency and electrochemical equivalent in an electrolytic process

Calculations of current efficiency of an electrolytic reaction and of electrochemical equivalent of the metal involved are discussed. A formula for the electrochemical equivalent of a ternary alloy is also give

Electrodeposition of black chromium from self regulating electrolytes

A strong need islelt by a practical plater for a black chrome bath which can be operated around the ambient temperature (30°C) and at normally employed current densities and preferably not associated with any necessity of controlling the catalyst concentration. In the work now reported, experiments were carried out on the solubility of calcium fluoride gt 30°C in chromic acid solutions with a concentration range of .200- 425 g 1 I. Barium hydroxide was introduced in adequate quantities to desulphate chromic acid and also to counteract any drag-in of sulphate. Hullcell experiments were carried out at 23" and 31°C in order to assess approximately the cunent density range over which black chromium deposition was possible. This was followed by experiments in plating to study the effects of different parameters like chromic acid concentration, current density. temperature and duration of deposition on the nature of finish and deposition

Thiosulphate baths for silver plating

Electroplating silver from thiosulphates solutions has received increasing attention recently because of the emphasis on pollution-free prooesses. This paper reports the results of studies for identifying suitable compositions for silver plating. Different aspects encompassing stability, mnductivity, cathode current efficiencv. deposition rate and throwing power of solutions as well as deposit properties like appearance. microhakness and adhesion were examined. The preplating sequence fro improving deposit adhesion was also investigated. The studies enabled identification of two methods of wetreatment and production of sound deposits with good adhesion to copper and.nickel plated copper. specimens

Palladium plating for electronic applications

Palladium has been found to be a viable alternative to gold for contact surfaces in the electronic industry on account of iD low cost, good resistance to corrosion and tarnishing, good solderability and good electrical conductivity. The present papa deals with the palladium bath performance, deposit characteristics and bath stabilit