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A Review of Recent Technology Advancements on Smart Cities and its High-Performance Applications
Get PDFEconomic, social, and technical developments require the geographical regional development of a nation. People from various parts of the country migrate to city area where these developments are a continuous proven process. This migration
(urbanization) stimulates many challenges and requires an innovative solution so as to provide a better environment to the citizens of developing countries. Many research and resolution models have been implemented to address the core issues.
In this paper, we survey the necessities and issues of urbanization, and different views of high-performed smart city applications. We also surveyed some of recent advancements of smart city’s applications, development progress, and
future directions of different category (e.g., domain, technology, system, and data) of common challenges. This article is a well-suited reference to the scholars and researchers for smart cities’
research contribution
Internal Heat Modulation on Darcy Convection in a Porous Media Saturated by Nanofluid
Get PDFIn this paper we investigate the effect of internal heat modulation over a nanofluid saturated porous medium. We consider a small variation in time dependant heat source and vary sinusoidally with slow time. An energy equation will be altered by adding time dependant internal heat source. This internal heat source has its time dependent and independent parts. Time dependent part shows that the internal heat modulation over a porous media and defines controls on heat/mass transfer in the layer. We have performed a nonlinear stability analysis to investigate heat/mass transfer in the system. The nonlinear system of partial differential equations are transformed into nonlinear ordinary differential equations under similarity transforms up to the second term. This system has different system parameters and they have been investigated on heat and mass transfer graphically. The dual nature, stabilize or destabilize is due to the significant effect of internal heating modulation of the system. Further, the effect of internal heating is to destabilize the system, as a consequence heat/mass transfer enhances. It is found that internal heating modulation can be used effectively to regulate heat/mass transfer in the system
Book Title: Solvent‐Free Methods in Nanocatalysis: From Catalyst Design to Applications (Wiley)
No full textSince the realization that the future of chemical/industrial processes primarily depends on their sustainable quotient, the path of modern science has shifted toward the improvement of processes/products following green chemistry princi�ples [1, 2]. Green chemistry as a branch of chemistry primarily deals with developing chemical processes using environmentally benign protocols, including inexpensive renewable less-toxic precursors. In that respect, the “12 rules of green chemistry,”
first formally introduced by Anastas and Warner in their book “Green Chemistry: Theory and Practices” [3], play a pivotal role in identifying the areas that should be focused to achieve the expected sustainability goals [4]. For chemical processes,
the main aim of introducing these 12 principles is to save the environment and society by reducing the usage of toxic and hazardous chemicals and solvents without affecting the product yield/selectivity. While the 12 principles are quite
self-explanatory, as depicted in Figure 1.1, the emphasis in certain areas often depends on the convenience of implementing them for specific protocols and the
outcome. Of these 12 principles, this book focuses on the historical and recent developments of strategies that minimize solvent use in a chemical process, often termed “solvent-free synthesis,” and the associated catalytic procedures involving
nanomaterial
A computational finding on the effect of π-conjugated acceptors in thiophene-linked coumarin dyes for potential suitability in DSSC application
No full textAbstract
Herein we studied the potential suitability of four thiophene-linked coumarin dyes in dye�sensitized solar cells (DSSCs) application by employing density functional theory (DFT) and
time-dependent DFT methods. The new four dyes comprise various π-conjugated acceptor moieties, such as quinazolinone-N-acetic acid, indoline carboxylic acid, rhodanine acetic acid,
and homophthalimide-N-acetic acid with dialkylamino coumarin as donor and thiophene as a common spacer. We have investigated the influence of the π-conjugated acceptor moieties in thiophene-linked coumarin dyes on the photovoltaic performance and adsorption onto the TiO2 surface. The π-conjugation in the acceptor moiety enhanced the intensity of the ICT band and which has been corroborated by the NBO data. C3 dye showed higher charge separation (∆q D–A
) between the coumarin donor and rhodanine acetic acid acceptor moieties and which revealed a higher red-shift in the absorption spectra for C3 dye. The photophysical,
electrochemical properties and photovoltaic parameters of DSSCs have been calculated to assess their suitability for the application in DSSCs. The higher dye regeneration driving force,
higher lifetime, and higher power conversion efficiency values (calculated) make dye C3 the potential candidate for DSSCs among all the studied dye
Development of an optical biosensor for the determination of choline in human biofluids
No full texta b s t r a c t
An optical biosensor was developed for choline from a (E)-1-(4-aminophenyl)-3-(4-(dimethylamino) phenyl)prop–2-en-1-one (4ADP). The biosensor showed strong adsorption of choline in 4ADP with low detection limit of 21 nM was exhibited. This choline sensor 4ADP has been applied to the analysis of
choline in serum samples also the binding interaction has been confirmed by NMR titration, FTIR and DFT study. A set of experimental results indicate that the chalcone derivative selectively detects choline in the presence of other biomolecules with 1:1 binding stoichiometry through ICT mechanism
Highly selective detection of citrulline using curcumin analogue and its application in food samples with logic gate behaviour
No full textABSTRACT
A new curcumin-based biosensor (E)-5-(4-hydroxyphenyl)-1-phenylpent-4-ene-1,3‑dione (5HPD) was success�fully synthesized for the selective detection of citrulline (Cit). Job’s plot analysis indicated, a 1:1 binding stoi�chiometry between the sensor (5HPD) and citrulline. The binding constant was estimated to be 3.55 × 107 M− 1 according to the Stern Volmer method. The newly synthesized sensor 5HPD is highly selective detection towards citrulline with various competitive biomolecules. Linearity ranges of 10 - 60 μM and lower detection limits is 75 nM. Interestingly, a reversible process provoke successively by 5HPD, Cit with EDTA observed and molecular
logic circuits. The Mechanism of sensing 5HPD-Cit has been characterized clearly by 1 H NMR, FTIR, ESI-MS
spectroscopy and DFT calculation
Simulation Based Investigation of Triple Heterojunction TFET (THJ-TFET) for Low Power Applications
No full textWe designed a new model tunnel feld-efect transistor (TFET) based on Triple Heterojunction Tunnel Field Efect Transistor
(THJ-TFET) is investigated and designed in this paper. This structure has a complex body with a metal oxide semiconductor
feld efect transistor. The integral switching mechanism of Triple Heterojunction TFET difers from conventional TFET
and its construction, analytical modeling, and BTBT operations are well suitable for low power electronics. Here triple het�erojunction (THJ) tunnel feld-efect transistor (THJ-TFET) has been recommended to fnd the solution for less power usage
test for new designs. The Triple Hetero junction TFET device is made up of semiconductors like silicon (Si), Silicon Dioxide
(SiO2), Hafnium Oxide (HfO2), and Titanium Dioxide (TiO2) materials are very potential. The Triple Hetero Junction-Tunnel
FET device layout with 60 nanometers dimensions and an overall gate length of 5 nm technology is used for the designing
of the proposed device (THJ-TFET). The THJ-TFET structure is invented using the TCAD tool with a channel length of
5 nm innovations. Hence Triple Hetero Junction TFET device achieved 5% more drain current (Ion) and has calibrated all
the analog parameters and RF parameters
Impact of metal mould vibration on the mechanical properties of aluminium 6082 t6 alloy
Get PDFCasting is a technique used to prepare machinery parts. Casting during vibration is one of the techniques used to improve the properties of material. In this paper, the effect of mould vibration on the properties of gravity die casting alloys is studied. This process decreases the porosity, holes and increase in the grain refinement of cast alloy. Aluminium 6082 T6 alloy is made by casting process, with and without vibration. The frequencies varied from 0 Hz to 45 Hz. The material is tested on electronic tensiometer and vickers hardness to check its tensile strength and hardness. The outcomes showed improvement in grain refinement and properties when vibration is applied during casting. With this improvement, it can be widely used in trusses, bridges, cranes and transport applications
Identifcation, Isolation, and Structural Characterization of Novel Forced Degradation Products of Darunavir Using Advanced Analytical Techniques Like UPLC–MS, Prep‑HPLC, HRMS, NMR, and FT‑IR Spectroscopy
Get PDFSince the stability of the pharmaceuticals plays a crucial role in efcacy and safety while using them in the treatment of disorders, the evaluation of purity and impurity profling of pharmaceuticals is of utmost importance using efcient analytical techniques. The present study explains the identifcation, isolation, and characterization of stress degradation products of the anti-human immunovirus drug Darunavir. The degradation study was performed to evaluate the stability profle of Darunavir in diferent stress conditions like hydrolytic, oxidative, thermal, and photolytic conditions as per the ICH guidelines. Degradation products were identifed using ultra-performance liquid chromatography coupled with mass spectrometry, isolated using semi-preparative high-performance liquid chromatography, and structural characterization by HRMS and 1H,13C NMR (1D, 2D). Darunavir is relatively stable in oxidative, thermal, and photolytic conditions; however, considerable degradation was observed in acid and base hydrolysis. A total of fve degradation products were identifed and isolated in acid and base degradation. DP-1, DP -2, & DP-3 were observed in acid conditions, whereas in base conditions, along with DP-2, two more DPs, i.e., DP-4 & DP-5, were identifed. Among the fve DPs, two degradation products, namely DP-1:
N-(4-(N-(3-amino-2-hydroxy-4-phenylbutyl)-N-isobutylsulfamoyl) phenyl) acetimidamide. & DP-3: hexahydrofuro[2,3-b] furan-3-yl(4-((4-acetimidamido-N-isobutylphenyl)sulfonamido)-3-hydroxy-1-phenylbutan-2-yl)carbamate, are novel, remaining degradation products DP-2: 4-amino-N-(3-amino-2-hydroxy-4-phenylbutyl)-N-isobutylbenzenesulfonamide, DP-4: 4-amino-N-(((5S)-4-benzyl-2-oxooxazolidin-5-yl) methyl) -N-isobutyl benzenesulfonamide and DP-5: methyl ((3S)-4-((4-amino-N-isobutylphenyl) sulfonamido)-3-hydroxy-1-phenylbutan-2-yl) carbamate are already reported tentatively using a single analytical technique coupled with mass analysis without any evidence from NMR and IR data. Hence, the present study focused on using High-Resolution Mass, 1D, and 2D 1H, 13C NMR data for concrete confrmation of structures for degradation products
OPTIMIZATION OF QUERCETIN LOADED FAST DISSOLVING FILMS BY EMPLOYING QBD AS A DESIGNING TOOL FOR IMPROVED BIOAVAILABILITY
Get PDFQuercetin was found to be BCS class-4 molecule with desired cancer preventive activity but characterized by lower solubility and permeability. To overcome the issues associated with Quercetin, the current research was designed for the development of cyclodextrin based inclusion complexes loaded orally fast dissolving films (ICQF). For the preparation of ICQFs, the film former, plasticizer and the super disintegrant was selected as methyl cellulose, PEG 400, either croscarmellose sodium/ starch citrate respectively. To develop the formulation with desired properties, box behnken design of quality by design (QbD) was employed and the same was analyzed to find the optimized combination of different variables. The ICQFs were evaluated for their physical characterization, drug content and disintegration time of the ICQFs were observed to be in the range of 0.13-0.27 mm, 447-663, 6.6-10.4 MPa, 20.4-30.7%, 96.3-102.4% and 32-312 sec. respectively. Along with the physico chemical characterization, the ICQFs were evaluated for its dissolution and pharmacokinetic behavior. The effect of different factors were studies on the desired responses like disintegration time and dissolution after 10 minutes (D10). From the graphical optimization, a fresh formulation was prepared with 500 mg of film former, 1.16% v/v of plasticizer and 7.5% of super disintegrant. The DT and D10 for the optimized formulation was found to be 32.9 sec. and 82.4% respectively. Along with the in-vitro performance, the in-vivo behavior was also evaluated by performing the pharmacokinetic study using male Sprague–Dawley (SD) rats and the bioavailability of the formulation found to be improved in comparison to the plain drug suspension. The investigation was found to be innovative with successful attainment of the hypothesis