Electrodeposited Cu-based Catalysts for Alcohols from CO Hydrogenation and Electrodeposition of CuNiW/CuNi Multilayered Alloys

Ethanol and higher alcohols can be used as a fuel or fuel additive in gasoline engines as well as a hydrogen carrier. One of the promising methods to synthesize these alcohols is based on thermochemical conversion of CO and H2 (CO hydrogenation). Conventional catalysts used for the conversion CO and H2 (syngas) to ethanol typically give yields less than 20% with the balance resulting mostly in the formation of the thermodynamically favored products CH4 and CO2. New catalysts with compositions designed to kinetically favor the formation of ethanol and higher alcohols are needed. Electrodeposition of nanowires offers a means to control the surface properties of multimetallic catalysts in a way that is not possible with conventional catalyst preparation methods such as co-precipitation and impregnation. A principle advantage of electrodeposition over conventional methods centers on its ability to control the active metal environment at the atomic level. In this work, Cu-ZnO and Mn-Cu-ZnO novel nanowire/tube catalysts have been prepared by electrodeposition using a template synthesis technique. To the best of our knowledge, electrodeposited Cu-based nanowires have never been used as heterogeneous catalysts. Different current and pulsed current schemes were used to control composition and morphology of the resulting nanowire/tube catalysts. Pulse waveforms with suitable on-time (cathodic current) and off-times (no current) were used to tailor the atomic environment of the nanowire catalysts. A fixed bed tubular reactor was used to synthesize alcohols from CO and H2 (syngas). In addition to C2-C4 alcohols products of interest, methanol, methane, propylene, and CO2 were the main side products at various reaction conditions. The reaction was performed at varying temperature (250C-310C), pressure (10-20 bar), H2/CO ratio (1-3), and GHSV (7,500-33,000 scc/h-gcat). The addition of Mn to the Cu-ZnO catalyst increased the selectivity toward ethanol and higher alcohols by reducing methanation. Schulz-Flory distributions of the products suggest that the synthesis of alcohols and hydrocarbons require different sites

Framework to Analyze Customer’s Feedback in Smartphone Industry Using Opinion Mining

In the present age, cellular phones are the largest selling products in the world. Big Data Analytics is a method used for examining large and varied data, which we know as big data. Big data analytics is very useful for understanding the world of cellphone business. It is important to understand the requirements, demands, and opinions of the customer. Opinion Mining is getting more important than ever before, for performing analysis and forecasting customer behavior and preferences. This study proposes a framework about the key features of cellphones based on which, customers buy them and rate them accordingly. This research work also provides  balanced and well researched reasons as to why few companies enjoy dominance in the market, while others do not make as much of an impact

Design of self-cured geopolymer concrete using Taguchi approach

Geopolymer concrete is the most suitable alternative to conventional concrete. It needs high-temperature curing to achieve better mechanical and durability properties, which is not possible on many Indian construction sites. Therefore, this research explores the effect of Variables like the quantity of aluminosilicate material (ASM), the ratio between Alkaline solution to the quantity of aluminosilicate material (AL/ASM), sodium silicate and sodium hydroxide ratio (SS/SH), and molarity of sodium hydroxide (SH) on the compressive strength and water absorption of Self-Cured Geopolymer Concrete (SCGC). The aforementioned properties have been optimized using the Taguchi approach and non-destructive testing (NDT) has also been performed on SCGC specimens. Along with the experimental work, a mathematical model was also developed using multiple regression analysis for predicting the compressive strength and water absorption of SCGC specimens. SCGC has been developed in an environment where temperature and humidity are not controlled. The experimental results inform that the specimen with ASM of 450 kg/m3, AL/ASM ratio of 0.45, SS/SH ratio of 1.5, and molarity of SH 12M provides maximum compressive strength and minimum water absorption. The pattern of the Signal-to-noise ratio (S/N) curve of the NDT is alike to that of the destructive tests (DT). The findings predicted by the polynomial regression equations are identical to the experimental results compared to the linear regression equation. It has also been found that SCGC of M25 grade can be developed without controlling temperature and humidity. 

Replacement of Natural Aggregates in Geopolymer composites - A brief review

Natural aggregates are essential constituents of both conventional and geopolymer concrete, which fills up approximately 60–80% of the total volume and have a direct impact on the properties of concrete. The extensive use and the high extraction of the natural aggregates raise questions regarding the conservation of natural aggregates' resources and environments. Therefore, several researchers incorporated some recycled aggregates and waste or by-products (WBP) like copper and steel slag, granite quarry sand, crushed sand, etc. as the substitution of natural aggregates. This literature provides a brief review of the properties of the geopolymer composites when natural aggregates are partially or fully replaced. Several previously published literature has been studied and found that the utilization of recycled aggregates and WBP (to a certain extent) into geopolymer concrete has enhanced physical, mechanical, and durability properties, as well as forming a dense structure. Based on the study, it can be concluded that recycled aggregates and WBP have the potential to partially replace natural aggregates (fine as well as coarse)

In-vitro sperm immobilization activity and biocompatibility study of NVD terpolymer

Background: Boronate derivatives have been used in affinity chromatography for separation of cells based on their glycoprotein content. Boronate containing polymers when used intravaginally before sexual intercourse could bind to the glycoproteins present on sperm cell surface and render them immobile, which potentially may work as female-controlled contraceptive. To study this hypothesis NVD terpolymer which contains boronic acid was studied on goat sperm and its biocompatibility was accessed on NIH3T3 fibroblast.Methods: Sperm motility study was carried out on goat sperm cells. The study was divided into two groups, test group (NVD terpolymer in simulated vaginal fluid) and negative control (simulated vaginal fluid only) performed using Sander-crammer assay. In the test group, the study was started from 0.1 % of the polymer solution, until the half of the sperms became non-motile as compared to normal control. The biocompatibility study was performed by culturing the NIH3T3 fibroblast with different concentrations of NVD polymer, followed by cell viability assay by performing 3-(4, 5-dimethylthiazol-2-Yl)-2, 5-diphenyltetrazolium bromide (MTT) assay at 6, 12 and 24 hour spectrophotometrically.Results: Sander-crammer assay resulted in significant (P-value < 0.05) decrease in motile sperm count in test group when compared to control. At 7.5 % concentration, the half of the sperms rendered immobile, and this was termed as effective concentration 50 (EC50). In-vitro biocompatibility study using NIH3T3 fibroblasts culture and MTT assay with cultured cells at 6, 12 and 24 hour, revealed that the polymer is biologically compatible as there were no significant change (P-value < 0.05) in the absorbance.Conclusions: Boronate containing polymer, such as NVD terpolymer has in-vitro sperm immobilizing activity in goat sperm model, with further research in this area could yield a potential female control contraceptive agent