Comprehensive adsorption characteristics of a newly synthesized and sustainable anti-corrosion catalyst on mild steel surface exposed to a highly corrosive electrolytic solution

Kumar, Raman,Kim, Hansung,Umapathi, Reddicherla,Yadav, Ompal Singh,Singh, Gurmeet Elsevier 2018 Journal of molecular liquids Vol.268 No.-

<P><B>Abstract</B></P> <P>A new environmental-friendly imine compound viz. 4-(2-amino-3-methylphenyl)imino)methyl)benzaldehyde (AMIB) was sustainably synthesized at room temperature utilizing green solvents, reagents and assessed as an anti-corrosion catalyst for the commercially important mild steel (MS) alloy subjected to highly aggressive 0.5 M sulphuric acid (H<SUB>2</SUB>SO<SUB>4</SUB>) solution by several electrochemical methods (polarization techniques and Electrochemical impedance spectroscopy) allied with various surface characterization techniques such as attenuated total reflectance (ATR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and atomic force microscopy (AFM). Furthermore, the experimental results were theoretically supplemented by density functional theory (DFT) treatment. AMIB delivered significant corrosion protection even at very low concentrations and at various temperatures. The findings from electrochemical and surface characterization techniques were also supplemented by temperature kinetics study. The adsorption mechanism of AMIB molecules on metal substrate follow Langmuir's adsorption isotherm. The overall corrosion mitigation mechanism assessed from various techniques and methods was found to be comprehensive in nature. The present study may pave the way for combating corrosion with this cost effective and eco-friendly strategy.</P> <P><B>Highlights</B></P> <P> <UL> <LI> AMIB has been synthesized in green solvents at room temperature. </LI> <LI> Sustainable inhibition behavior has been observed for mild steel (MS) Corrosion. </LI> <LI> Significant inhibition efficiency has been achieved at a very low concentration (1 mM). </LI> <LI> Substantial corrosion mitigation performance has been observed at high temperatures. </LI> <LI> The MS surface has been protected via comprehensive adsorption. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

High Temperature Sliding Wear Behaviour of Ti6Al4V Thermal Oxidised for Different Oxidation Durations

Kamini Singh,S. Ganesh Sundara Raman 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.2

Most of the available literature discusses the room temperature tribological behaviour of thermal oxidation (TO) treatedTi6Al4V. There is only a few literature on the high temperature wear behaviour of TO-treated Ti6Al4V. Oxidation durationplays an important role in harnessing the benefit of solid solution strengthening from oxygen. No data is available on theeffect of TO duration on the high temperature wear behaviour of TO-treated Ti6Al4V. Therefore, in the present investigation,Ti6Al4V was thermally oxidised at the optimised temperature of 650 °C for different oxidation duration of 16 h, 24 h,and 48 h, and its sliding wear behaviour was investigated at room temperature (RT) and 450 °C. Sliding wear studies werecarried out using the ball on disk configuration against alumina as the counter body in dry condition. Wear characterisationwas done using an optical profilometer, a scanning electron microscope, and a Raman spectrometer. Results showedthat TO-treated samples showed reduced wear volume loss, i.e. improved wear resistance at RT and 450 °C. Wear volumeloss was the least for TO-treated samples oxidised for 16 h, 90% less than that of untreated coupons at RT and 77% less at450 °C. TO duration of 48 h degraded wear performance, increasing wear volume loss due to oxide failure at 450 °C. Themorphological study indicated an abrasive mechanism for untreated samples at RT and oxidation and delamination wear at450 °C, while TO-treated samples showed a delamination mechanism with fracture of the TiO2layer.

Skew Detection and Correction of Gurmukhi Words from Natural Scene Images

Balwinder Singh,Raman Maini 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.9

Natural scene images are more susceptible to skew deformation as compared to document text which makes skew correction an indispensable step in scene text extraction. This work evaluates Murthy’s Devanagari scene word slant correction method [Signal, Image and Video Processing, 7(6), 2012] on Gurmukhi scene images. The method makes use of headline feature of Devanagari which also exist in Gurmukhi script. The headline of Gurmukhi word is found by perceiving farthest located salient points as its end-points and skew angle of headline is calculated from its slope. Gurmukhi word image is de-skewed using skew angle of identified headline. The method has been tested on 100 self-captured good quality Gurmukhi and 117 publically available Devanagari scene words with average accuracy of 62.8% and 72.2% respectively. The method has been found to be working well on few samples of defective scene words, provided actual end-points of headline are preserved. It has been observed that Murthy’s method is very simple to implement, does not require any pre-processing and give good results in wide variety of practical situations. However, this method does not work well for single character words with vowel above headline and words with identified headline parallel to horizontal axis.

Experimental and theoretical investigations of a newly synthesized azomethine compound as inhibitor for mild steel corrosion in aggressive media: A comprehensive study

Kumar, Raman,Kim, Hansung,Singh, Gurmeet Elsevier 2018 Journal of molecular liquids Vol.259 No.-

<P><B>Abstract</B></P> <P>A new azomethine compound viz. 3-(2-amino-4,5-dimethylphenyl)imino)methyl) benzaldehyde (ADMB) was synthesized following a greener approach at room temperature and its anti-corrosion characteristics for mild steel (MS) corrosion were examined at various temperatures (298K to 328K) and concentrations (1mM to 0.001mM) in 0.5M H<SUB>2</SUB>SO<SUB>4</SUB> via electrochemical methods allied with surface characterization techniques. The adsorption of the ADMB molecules on the metal surface follows Langmuir's adsorption isotherm. To ascertain the mode of adsorption process, various adsorption and activation parameters were evaluated. Surface characterization studies viz. ATR-FTIR, SEM, AFM and EDS depict the formation of protective layer of ADMB on MS specimen. Density functional theory (DFT) treatment of ADMB established that the lower energy gap (ΔE) between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) resulted in significantly high inhibition efficiency. These results have shown that ADMB act as an effective inhibitor for MS corrosion in H<SUB>2</SUB>SO<SUB>4</SUB>. The inhibition efficiencies predicted from experimental measurements are in agreement with the theoretically evaluated parameters and results of spectroscopic techniques.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A new and efficient inhibitor (ADMB) synthesized at using green solvents. </LI> <LI> At low concentrations of ADMB it shows very effective inhibition characteristics. </LI> <LI> Inhibitor is of mixed type with slightly anodic action. </LI> <LI> The adsorption of ADMB on mild steel surface is comprehensive in nature. </LI> <LI> Surface characterization studies enhanced mechanistic details. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

An Algorithm for Spectrum Sensing in Cognitive Radio under Noise Uncertainty

Deep Raman,N. P. Singh 보안공학연구지원센터 2014 International Journal of Future Generation Communi Vol.7 No.3

Radioprotective and Antioxidant Activity of Fractionated Extracts of Berries of Hippophae rhamnoides

Rakesh Kumar Sharma,Raman Chawla,Rajesh Arora,Shikha Singh,Ravinder Kumar Sagar,Raj Kumar,Ashok Sharma,Manju L. Gupta,Surender Singh,Jagdish Prasad,Haider A. Khan,Anand Swaroop,A.K. Sinha,A.K. Gupta,R 한국식품영양과학회 2007 Journal of medicinal food Vol.10 No.1

Plants are an abundant source of medicinal compounds, some of which are useful in combating free radical-1002 (flavonoid-poor fraction) of Hippophae rhamnoideswere screened on the basis of their reducing power in the aqueousphase. REC-1001 was selected for further study, since it exhibited 27.38 times higher antioxidant activity than REC-1002.REC-1001 also showed significant (P. .05) membrane protection potential at 50 .g/mL, which was attributed to its abilityto scavenge peroxyl radicals (64.82. 1.25% scavenging within 1,440 min). A significant (P. .05) difference of 67.02% infree radical scavenging activity at 1,000 ng/mL between REC-1001 and vitamin E demonstrated the extract fraction’s worthc-tion. Further, REC-1001 was found to be nontoxic up to 200 mg/kg of body weight. This research suggests that the REC-1001 fraction of H. rhamnoidesextract is a safe and effective antioxidant nutraceutical product.

Surface Potential and Drain Current 2D Analytical Modeling of Low Power Double Gate Tunnel FET

Dhruv Garg,Girish Wadhwa,Shailendra Singh,Ashish Raman,Balwinder Raj 한국전기전자재료학회 2021 Transactions on Electrical and Electronic Material Vol.22 No.6

This submitted work presents the 2-dimensional analytical modeling of Tunnel FET’s in consideration with the inherent properties of dual modulation effect. This eff ect explains the concept of regulating both gate and also the drain terminal biasing voltage on device surface potential and hence on the tunneling drain current model, which uses the device surface potential modeling as basis of deriving the TFET current model. The model is developed using basic 2-D Poisson’s equation. This analytical model embraces both the biasing voltage effect at gate and drain terminal respectively. The results procured from the submitted work are in perfect agreement with TCAD simulations results and depletion width of various regions defi ned in TFET is accurate and can also be explained theoretically.

Chemical constituents, pharmacological activities, and uses of common ayurvedic medicinal plants: a future source of new drugs

Parul Kaushik,Priyanka Ahlawat,Kuldeep Singh,Raman Singh 경희대학교 융합한의과학연구소 2023 Oriental Pharmacy and Experimental Medicine Vol.23 No.3

Natural products, especially plants and herbs, have always been a common medicament source, either as pure active principles or traditional preparations. Traditional medicine has been used in developing and developed countries for centuries, and still, 80% of the population uses plant-based medicines for their health care needs. The present review discusses all the possible pharmacological activity reported in various literature and active chemical constituents of herbs. A list of various herbs/plants used by Ayurvedacharya Ratiram Sharma (93-year-old and practicing since 1952) and mentioned in Ayurvedic texts. The curated list was prepared by their general availability in the household and local market. This study comprehensively documented the medicinal value of sixty-six dominant plant species used in Ayurveda and local people. In the present review, each herb is discussed with its scientifc and common names, geographical distribution, traditional medicinal uses, benefcial plant parts, and active chemical constituents. For each plant, pharmacological activities of diferent parts of plants are displayed with their chemical constituents and structure. Toxicologists, phytologists, medicinal chemists, and other researchers who are interested in the various therapeutic and related applications of plant materials will be benefted from present review. This information will open new horizons of application for the many novel drugs and drug candidates.