Explicit input link rotatability analysis of Watt six-link mechanisms

Gunesh R. Gogate 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.7

This paper presents explicit input link rotatability analysis of Watt six-link mechanisms. Analysis is presented for all slider-crank based Watt mechanisms having up to three prismatic joints, and for four-bar based Watt mechanisms having two prismatic joints. Apart from being of theoretical importance, the presented analysis is suitable for implementation within an optimization scheme and is computationally efficient. When incorporated within an evolutionary optimization algorithm, it can also be used to effectively handle the rotatability constraint.

Unified synthesis of Watt-I six-link mechanisms using evolutionary optimization

Gunesh R. Gogate,Sanjay B. Matekar 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.8

A Watt-I mechanism can operate in eight different combinations of assembly modes and output link. In this paper, a novel approach ispresented for carrying out unified optimum synthesis of various combination types of Watt-I mechanism, irrespective of whether identicalor different ranges of variables are specified for different combination types. By carrying out unified synthesis the less suited combinationtypes can be identified, leading to their elimination from the synthesis process. This results in a saving of the overall computationaltime. The presented approach can be implemented with most of the evolutionary optimization methods. In this paper, the DifferentialEvolution algorithm is chosen as the optimization method. Unified optimization results are presented for two problems. The proposedapproach is general and can be used, with suitable modifications, to carry out unified optimum design of alternate mechanical systemswhich can perform a given task.

Photocatalytic and Sonophotocatalytic degradation of alachlor using different photocatalyst

Bagal, Manisha V.,Gogate, Parag R. Techno-Press 2013 Advances in environmental research Vol.2 No.4

The degradation of alachlor has been investigated using sonolysis (US), photocatalysis (UV) and sonophotocatalysis (US/UV) using three photocatalyst viz. $TiO_2$ (mixture of anatase and rutile), $TiO_2$ (anatase) and ZnO. The effect of photocatalyst loading on the extent of degradation of alachlor has been investigated by varying $TiO_2$ (both types) loading over the range of 0.01 g/L to 0.1 g/L and ZnO loading over the range of 0.05 g/L to 0.3 g/L. The optimum loading of the catalyst was found to be dependent on the type of operation i.e., photocatalysis alone or the combined operation of sonolysis and photocatalysis. All the combined processes gave complete degradation of alachlor with maximum rate of degradation being obtained in the case of sonophotocatalytic process also showing synergistic effect at optimized loading of photocatalyst. About 50% to 60% reduction in TOC has been obtained using the combined process of sonophotocatalysis depending on the operating conditions. The alachlor degradation fitted first order kinetics for all the processes under investigation. It has been observed that the $TiO_2$ (mixtrure of anatase and rutile) is the most active photocatalyst among the three photocatalysts studied in the current work. The effect of addition of radical enhancers and scavengers on sonophotocatalytic degradation of alachlor has been investigated in order to decipher the controlling mechanism. The alachlor degradation products have been identified using LC-MS method.

Highly efficient bi-metallic bismuth-silver doped TiO2 photocatalyst for dye degradation

Nandana Chakinala,Parag Ratnakar Gogate,Anand Gupta Chakinala 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.12

Several mono-and bi-metallic photocatalysts with different loadings have been synthesized using ultrasound assisted sol gel and wet impregnation methods. Synthesized catalysts were characterized using various analytical techniques to determine the bandgap, functional groups, crystallinity, and surface morphology. Photocatalytic performance of the different catalysts was compared in terms of Rhodamine-B dye degradation, and further process optimization studies were carried out to achieve the maximum extent of degradation. Catalyst performance was studied both under UV and visible light irradiation for the degradation of different dyes. Compared to pure TiO2 and monometallic Ag or Bi doped on TiO2, bi-metallic Bi-Ag on TiO2 catalyst synthesized using wet impregnation was found to be highly active under the conditions investigated. Complete degradation (~100%) was obtained within shorter duration in the presence of minimal catalyst loading (60mg/L). Overall, this work has clearly demonstrated the higher catalytic activity of bi-metallic catalyst, which is attributed to the synergistic effect of Bi and Ag on TiO2 facilitating the efficient charge separation and improved e transfer combined with high ability to absorb in visible light region in effectively degrading organic pollutants.

Treatment of toluene, benzene, naphthalene and xylene (BTNXs) containing wastewater using improved biological oxidation with pretreatment using Fenton/ultrasound based processes

Lokeshkumar P. Ramteke,Parag R. Gogate 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.28 No.-

Improved biological oxidation based on pretreatment using combined Fenton and ultrasound inpresence of stirring as the best approach and use of modified activated sludge was demonstrated for thetreatment of wastewater containing benzene, toluene, naphthalene and o-xylene. The optimumpretreatment conditions were observed as initial pH of 3–3.5, Fe2+ dosage of 2.0 g L–1 and H2O2 dosage of1.0 g L–1 giving about 80–95% reduction in the chemical oxygen demand (COD) and favorable BOD5/CODvalue for the biological oxidation. Use of modified prepared activated sludge gave about 20–30% higherextent of degradation as compared to the conventional sludge types.

Ultrasound assisted synthesis of epoxidized sunflower oil and application as plasticizer

Anand P. Chavan,Parag R. Gogate 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

The effect of ultrasonic reactors on the epoxidation of sunflower oil was investigated using two differentsonochemical reactors such as ultrasonic horn and ultrasonic bath. The optimized parameters for thesynthesis were established followed by scale up studies. Use of combination of ultrasonic bath andmechanical agitation gavemaximum conversion to oxirane oxygen as 91.1%. The synthesized epoxidizedsunflower oil (ESNO) was used as plasticizer in polyvinyl chloride sheets and the performance wasevaluated by thermogravimetric analysis and mechanical testing methods. It has been established thatESNO plasticizer has ability to replace dioctyl phthalate (DOP) giving a sustainable and greener approach.

Microwave assisted persulfate induced degradation of sodium dodecyl benzene sulfonate

Pravin Sukharaj Bhandari,Parag Ratnakar Gogate 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.12

Microwave assisted persulfate induced degradation of sodium dodecyl benzene sulfonate (SDBS) was investigated, focusing on establishing the best conditions for maximum degradation. The study involving different persulfate based oxidants, such as potassium persulfate (KPS), ammonium persulfate (NH3PS) and sodium persulfate (NaPS), revealed that the extent of degradation as 98.3, 82.2 and 68.2% was obtained for the use of KPS, NH3PS and NaPS, respectively. The study of the effect of SDBS concentration (25-100mg/L), oxidant loading (0-3g/L) and power (140-350W) established that degradation decreased with an increase in the operating parameter beyond the optimum condition. Under optimized conditions using potassium persulfate (KPS) as an oxidant, 51.6% and 98.3% degradation of 50mg/L SDBS solution was obtained by conventional and microwave assisted chemical oxidation approach, respectively, under optimized conditions of power, oxidant loading, volume and time maintained as 280W, 2g/L, 250mL and 28min, respectively. Extending the conventional approach for 120min resulted in degradation of 92.5%, which establishes that microwave helps in reducing the treatment time significantly. Kinetic study revealed pseudo-first-order behavior for degradation of SDBS. Energy per order (EEO) for conventional and microwave assisted degradation was observed to be 840 and 317.33kWh/m3, respectively. Overall, microwave assisted persulfate induced degradation of SDBS has been established to be promising method giving rapid degradation and better economics.

Bilateral Free Floating Vitreous Cysts with Posterior Embryotoxon

( Yajuvendra Singh Rathore ),( Ozhukil K. Radhakrishnan ),( Nagbhushan Chougule ),( Abhay Lune ),( Renu Magdum ),( Parikshit Gogate ) 대한안과학회 2014 Korean Journal of Ophthalmology Vol.28 No.6