Decomposition of NOx and PM emission in Diesel Exhaust by Electrochemical reactor with Multilayered Electrodes

NOx emissions are highly poisonous and reactive gas liberated excessively from diesel engines. This work attempts to decrease NOx emissions by developing electrochemical reactor. The electrochemical reactor consists of electrochemical cells placed inside it. The electrochemical cells are fabricated by YSZ as an electrolyte middle layer coated with NiO -YSZ as cathode layer and Ag-YSZ as anode layer. The electrochemical cells are tested with diesel exhaust in a single cylinder dieselengine. By passing the variable voltage to the electrochemical cell, it is observed that up to 70% NOx reduction and 65% PM reduction was achieved with electrochemical cell. Further by coating the BaO NOx storage material, NOx reduction was reduced to 75% and PM reduction up to 70% was achieved. NOx reduction was greater with electrochemical cell -2.The presence of NOx storage material causes more NOx decompositions in the cathode layers. NOx decomposition also increases the oxygen concentrations, which further oxidizes the HC and PM emissions.The increase in NO decomposition was due to the increase in the ionic conductivity of the YSZ substrate. NOx reduction by electrochemical cell is a cost effective method. &nbsp

Water Sustainability: Current and Future Challenges at SRM Institute of Science and Technology, Chennai, India

SRMIST has healthy approach to sustainability, incorporating social economic and environmental principles that have been in place for nearly a decade implementing short and long-term sustainable objectives. SRMIST developed, maintained the estate, and the surrounding landscape, with due environmental impact and social values and implemented effective, efficient utility management measures, policies and procedures. The 2018/2019 UI Green Metric ranked SRMIST as 9 th in India and 392nd in Global Ranking overall and 264th rank globally and 9th rank in India for water parameter and 3rd in the Nation and 243rd globally and 2nd rank nationally and 42nd rank globally for water. SRM IST improved implementation of the water conservation and recycling program from 75% in 2018 to 95 % in 2019. Water efficient appliances increased > 70% and has a long-term commitment for conservation of water by regularly monitoring the use of water with regular meters. SRMIST has 20 RO plants running 24x7 collecting 31,000L per day for all and installing Ultra Filtration unit. SRMIST’s goal is to reduce per capita water consumption varies from 3.7m3 to 3.3m. Among the 4600 M3 waste water generated an average 4140 M3 wastewater is treated and recycled. Rainwater harvesting pits have been constructed in 65% college buildings and hostels is used for the water recharge in the campus and the rainwater stored in the roof tanks are used for toilet flushing

Mass transfer studies of Direct Orange 102 dye onto a non-conventional adsorbent

Activated carbon with surface area of 896 m2/g has been prepared from the wood of Thevetia Neriifolia Juss (TNJAC). The fitness of the prepared activated carbon is tested for its adsorption capability towards the textile dye direct orange 102 (DO102). On increasing the solution pH from 2 to 12, the percentage of DO102 adsorption increases from 41 to 75%. The adsorption kinetics is analyzed using pseudo-first order and pseudo-second order kinetic models. Pseudo-second order model is more appropriate to describe the adsorption kinetics with a correlation coefficient of 0.9311< r2< 0.9871. On analyzing the adsorption isotherm using Langmuir and Freundlich models, the adsorption of DO102 by TNJAC follows Langmuir type of isotherm with energetically homogeneous sorbent surface

Arachis hypogaea derived activated carbon/Pt catalyst: reduction of organic dyes

Activated carbon from agro waste groundnut (Arachis hypogaea) shell was prepared by chemical activation and used as support for dispersion of 5% platinum nanoparticles. The Pt nanoparticles were obtained by the reduction in hydrogen gas medium. The synthesized groundnut activated carbon/platinum catalyst was characterized by various techniques such as X-ray powder diffraction, electron microscopies and X-ray photoelectron spectroscopy. The catalytic behaviour of the synthesized catalyst was investigated by exploring it as catalyst for the reduction of various classes of dyes; namely, triphenylmethane dyes such as Malachite green, phenol red and bromophenol blue, xanthene dyes: rose bengal, rhodamine 6G, rhodamine B, thiazine dye: methyelene blue, azo dye: congo red and 4-nitrophenol by sodium borohydride in aqueous medium. Under suitable reaction conditions, for all tested dyes, cationic dyes were reduced at a faster rate than anionic dyes. The rate of reduction on the structure of dye and nature of catalyst was employed

GROWTH OF InAsxSb1-x LAYERS ON GaAs SUBSTRATES BY HOT WALL EPITAXY

We have studied the structural and electrical characteristics of InAsSb ternary layers grown on GaAs (001) substrates by hot wall epitaxy (HWE) at arsenic (As) reservoir temperature in the range from 220 to 290 °C. The growth rate of the epilayer is found to be decreased with increasing As temperature. This is attributed to the abundance of group V molecules to the growth surface, which suppresses the mass transport of Indium (In) atoms. A dramatic change in the surface morphologies of the samples has been observed by scanning electron microscopy. X-ray diffraction studies indicate that the arsenic composition of the layer can be controlled by manipulating As temperature. Hall effect results of the samples show that the electron mobility of the layer decreases with increasing As temperature

Effect of incinerated paper sludge ash on fly ash-based geopolymer concrete

U radu je prikazan razvoj veziva na bazi letećeg pepela i pepela dobivenog spaljivanjem papirnog mulja za pripremu geopolimernog betona. Uzorci za ispitivanje su pripremljeni s raznim postocima zamjene letećeg pepela pepelom iz papirnog mulja pri različitim uvjetima njege. Provedeno je ispitivanje tlačne čvrstoće, vlačne čvrstoće pri cijepanju i čvrstoće na savijanje te istraživanje mikrostrukture geopolimera. Povećanje čvrstoće geopolimernog betona s letećim pepelom i pepela iz papirnog mulja do 10 % pokazuje da postoje dobre perspektive za korištenje ovakvog tipa betona za ugradnju na licu mjesta.The development of fly ash and incinerated paper sludge ash blend as a source material for preparing geopolymer concrete is presented in the paper. The specimens were prepared with varying percentage of fly ash replaced by paper sludge ash under different curing regimes. The compressive strength, splitting tensile strength, and bending strength values were tested and geopolymer microstructure was analysed. The up to 10% increase in strength of geopolymer concrete containing fly ash and paper sludge ash shows that good prospects exist for the use of this type of concrete for cast-in-situ applications

Bypassing reproductive barriers in hybrid seeds using chemically induced epimutagenesis

The triploid block, which prevents interploidy hybridizations in flowering plants, is characterized by a failure in endosperm development, arrest in embryogenesis, and seed collapse. Many genetic components of triploid seed lethality have been successfully identified in the model plant Arabidopsis thaliana, most notably the paternally expressed genes (PEGs), which are upregulated in tetraploid endosperm with paternal excess. Previous studies have shown that the paternal epigenome is a key determinant of the triploid block response, as the loss of DNA methylation in diploid pollen suppresses the triploid block almost completely. Here, we demonstrate that triploid seed collapse is bypassed in Arabidopsis plants treated with the DNA methyltransferase inhibitor 5-Azacytidine during seed germination and early growth. We identified strong suppressor lines showing stable transgenerational inheritance of hypomethylation in the CG context, as well as normalized expression of PEGs in triploid seeds. Importantly, differentially methylated loci segregate in the progeny of “epimutagenized” plants, which may allow epialleles involved in the triploid block response to be identified in future studies. Finally, we demonstrate that chemically induced epimutagenesis facilitates hybridization between different Capsella species, thus potentially emerging as a strategy for producing triploids and interspecific hybrids with high agronomic interest

Ultrasonic Synthesis of Al-SBA-15 Nanoporous Catalyst for t-Butylation of Ethylbenzene

Mesoporous Al-SBA-15 ( Si / Al = 25 ) catalysts were synthesised by the ultrasonic (US) irradiation method at different time durations (1, 3, and 5 h) using the pluronic P123 triblock copolymer as a template. The synthesised catalysts were examined in detail by XRD, ICP-AES, N2 adsorption-desorption, SEM, TEM, FT-IR, and TGA characterization techniques. The characterization results reveal that the catalysts possess a well-ordered hexagonal mesoporous structure. The catalytic activity of synthesised materials was investigated in the tert-butylation of ethylbenzene at different reaction conditions, and their identified products are para-tert-butylethylbenzene (p-tert-BEB) and meta-tert-butylethylbenzene (m-tert-BEB). It was found that high ethylbenzene conversion (69%) is achieved at 200°C with high selectivity towards p-tert-butylethylbenzene (80%). The optimum feed ratio (ethylbenzene: t-butyl alcohol) was 1 : 2, and the feed rate was 2 ml/h for high conversion and product selectivity. All these synthesised Al-SBA-15 (US) catalysts are compared with hydrothermally synthesised Al-SBA-15 (HT) at the same reaction conditions