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Asian Journal of Pharmaceutical Sciences 2016年第5期11卷 603-617页

作者： Raj Mukherjee Vipul Gupta Shivangi Naik Saurabh Sarkar Vinit Sharma Prasad Peri Bodhisattwa Chaudhuri Department of Pharmaceutical Sciences University of ConnecticutStorrsCT 06269USA Institute of Material Sciences University of ConnecticutStorrsCT 06269USA Merck Sharp and Dohme West PointPA 19486USA

Particle sizes play a major role to mediate charge transfer, both between identical and different material surfaces. The study probes into the probable mechanism that actuates opposite polarities between two different size fractions of the same material by analyzing the charge transfer patterns of two different sizes of microcrystalline cellulose(MCC). Quantum scale calculations confirmed alteration of charge transfer capacities due to variation of moisture content predicted by multiple surface and bulk analytical techniques. Discrete Element Method(DEM) based multi-scale computational models pertinent to predict charge transfer capacities were further implemented, and the results were in accordance to the experimental charge profiles.

关键词： Tribocharging Work function Excipient Discrete Element Modeling

Design of Power System Stabilizer for DFIG-based Wind Energy Integrated Power Systems Under Combined Influence of PLL and Virtual Inertia Controller

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JOURNAL OF MODERN POWER SYSTEMS AND CLEAN ENERGY 2024年第2期12卷 524-534页

作者： Sahu, Balakrushna Padhy, Bibhu prasad Indian Inst Technol Ropar Dept Elect Engn Bara Phool 140001 Punjab India

Wind energy systems (WESs) based on doubly-fed induction generators (DFIGs) have enormous potential for meeting the future demands related to clean energy. Due to the low inertia and intermittency of power injection, a WES is equipped with a virtual inertial controller (VIC) to support the system during a frequency deviation event. The frequency deviation measured by a phase locked loop (PLL) installed on a point of common coupling (PCC) bus is the input signal to the VIC. However, a VIC with an improper inertial gain could deteriorate the damping of the power system, which may lead to instability. To address this issue, a mathematical formulation for calculating the synchronizing and damping torque coefficients of a WES-integrated single-machine infinite bus (SMIB) system while considering PLL and VIC dynamics is proposed in this paper. In addition, a power system stabilizer (PSS) is designed for wind energy integrated power systems to enhance electromechanical oscillation damping. A small-signal stability assessment is performed using the infinite bus connected to a synchronous generator of higher-order dynamics integrated with a VIC-equipped WES. Finally, the performance and robustness of the proposed PSS is demonstrated through time-domain simulation in SMIB and nine-bus test systems integrated with WES under several case studies.

关键词： Power system stability Phase locked loops Doubly fed induction generators Power system dynamics Rotors Frequency control Transient analysis Doubly-fed induction generator (DFIG) virtual inertia controller (VIC) phase locked loop (PLL) small-signal analysis synchronizing/damping torque synchronous generator power system stabilizer (PSS) FREQUENCY SUPPORT IMPACT

Dynamics of additional food provided predator-prey system with habitat fragmentation

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International Journal of Biomathematics 2023年第4期16卷 45-80页

作者： K.Durga prasad B.S.R.V.prasad Department of Mathematical and Computational Sciences Sri Sathya Sai University for Human Ercellence Kamalapur KalaburagiKarnataka 585313India Department of Mathematics School of Advanced Sciences VIT(Deemed to be University)Vellore Tamilnadu 632014India

Due to human-caused deforestation,global warming,and other environmental factors,habitat fragmentation became widespread.This fragmentation has a variety of detrimental repercussions for many species as well as humans,especially in the agricultural economy.It causes insect outbreaks,the expansion of alien species,and disrupts biological management by rendering the habitat unsuitable for natural enemies in agriculture.Providing natural enemies with additional food is one method to improve the ecosystem and support them.In this study,we assumed that the ecosystem is separated into two patches and that predators can easily migrate from one patch to the next,while prey stays inside its patch's territory.We looked at the impact of offering more food to predators in a patchy environment using dynamical systems theory.The permanence,stability,and various bifurcations that occur in the system are studied using a rigorous mathematical analysis.The study looks at how predator's access to other food sources affects pest management.By adjusting the provided food's characteristic qualities,such as(nutritional)quality and quantity,one can limit and manage the pest in one or both patches,as well as eliminate predators from the ecosystem.This research reveals that providing predators with additional food(of specified quality and quantity)can help in controlling chaotic behavior in the system.The findings of the study are supported by numerical simulations.

关键词： Pest predator additional food habitat fragmentation Hopf bifurcation chaos biological control

LDF based parametric optimization to model fluidized bed adsorption of trichloroethylene on activated carbon particles

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Particuology 2022年第6期20卷 72-92页

作者： Shradha Nikam Debapriya Mandal prasad Dabhade Homi Bhabha National Institute Mumbai 400094India Alkali Material and Metal Division Bhabha Atomic Research CentreMumbai 400085India

Trichloroethylene(TCE)is largely used in industries as a cleaning and degreasing solvent.TCE is a potential carcinogen and is known to cause organ damage when exposed to prolonged higher concentrations.Numerical simulation of fixed and fluidized bed adsorption of TCE can help in the development of efficient adsorption processes to prevent industrial workers in the vicinity from acute TCE exposure.In the present work,a parametric optimization based numerical experimentation algorithm is implemented by open-source computational solvers to model fixed and fluidized bed adsorption of trichloroethylene vapors on activated carbon.The algorithm optimizes four parameters pertaining to linear driving force(LDF)formulation of surface barrier and microporous diffusion.The optimized parameters were utilized to evaluateζ,a dimensionless number defined as the temporal and spatial average ratio of surface barrier diffusion resistance to microporous diffusion resistance.The average value ofζis 0.139 for fixed bed operation(u/u_(mf)=0.7),1.130 for fluidized bed operation(u/u_(mf)=1),4.436 for fluidized bed operation(u/u_(mf)=1.5)and 6.317 for fluidized bed operation(u/u_(mf)=2).Therefore,the dimensionless numberζmay serve to predict the extent of change in amount adsorbed per unit adsorbent mass with change in fluidization velocity.

关键词： Fluidization Adsorption Linear driving force Parameter optimization Trichloroethylene Activated carbon

CFD analysis for mixing performance of different types of household biodigesters

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Clean Energy 2022年第2期6卷 325-334页

作者： Sagar Shrestha Sunil prasad Lohani Renewable and Sustainable Energy Laboratory Department of Mechanical EngineeringKathmandu UniversityNepal

Household biodigesters are self-mixing anaerobic digesters used mostly in rural areas of developing countries as a reliable source of clean cooking energy.For an efficient anaerobic digestion process,the mixing of slurry inside the digester is regarded as one of the most important parameters.In this study,the mixing of slurry in three different designs of household digesters,namely the fixed-dome digester(GGC 2047 model),plug-flow digester and prefabricated plastic digester,are investigated and compared using compu-tational fluid dynamics.A 3D transient simulation is performed using a multiphase volume of fluid(VOF)model in Ansys^(■)Fluent release 16.0.The rheological properties of the feedstock are considered identical for all three digesters.The volume of the plug-flow and prefabricated plastic digesters is designed to be 1 m^(3) while the volume of the GGC 2047 digester was 6 m^(3) as the standard size of the household digester.The regions inside the digester where the velocity of slurry is<0.02 m/s are regarded as dead zones and the obtained results were analysed and compared using velocity patterns and dead-zone formation.It is found that the prefabricated plastic digester model has a relatively higher percentage of dead volume(74.6%)and the plug-flow digester has the lowest per-centage(54%)of dead volume among digesters that were compared in this study.The study will serve as the basis for designers and researchers to improve the design of household digesters for better mixing performances.

关键词： household biodigesters dead zone CFD anaerobic digestion mixing biomass Ansys Fluent

Fate and toxicity of nanoparticles in aquatic systems

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Acta Geochimica 2023年第1期42卷 63-76页

作者： Shikha Singh Sheo Mohan prasad Gausiya Bashri Ranjan Plant Physiology and Biochemistry Laboratory Department of BotanyUniversity of Allahabad211002 AllahabadIndia Department of Botany Aligarh Muslim University202001 AligarhIndia

Nanotechnology is a ground-breaking multidisciplinary fi eld across a broad spectrum of basic and applied sciences for producing and applying nano-sized materials for innovative solutions.The use of nanomaterials in industrial applications,medical products,and consumers has increased repeatedly over the last few years,and these applications will likely continue to grow.In an aquatic ecosystem,nanoparticles take entry through a direct route that includes industrial discharge,disposal of wastewater treatment e ffl uents,and indirect runof f from the soil.After reaching the aquatic environment,the nanomaterials are highly af fected by their backdrops and subsequently go through various conversions like agglomeration,aggregation,dissolution,sulfi dation,etc.The fate and the behavior of nanomaterials in the aquatic system not only depend on their physical-chemical properties but also on the pH,temperature,salinity,water hardness,and concentration of natural organic matter present in receiving water.In this review,emphasis has been given to the toxicological properties and potential risks of nanomaterials in terms of factors contributing to their toxicology,bioavailability,and accumulation in aquatic organisms as well as the environment.Furthermore,we summarize the published data on engineered nanoparticles’ef fect on aquatic organisms.The issues related to the accumulation and penetration of nanoparticles in the aquatic organism,their toxic ef fect,and biotransformation along with the food web are also discussed.Since nanomaterials are being increasingly released into aquatic bodies,it is important to pay greater attention to their toxicity and how it af fects the aquatic ecosystem.The nanomaterials are bioavailable to plants,resulting in trophic transfer,and they impact other organisms through biomagnifi cation,as discussed in this review.To close the enormous information gap,extensive research on the interactions and impacts of NPs on dif ferent species belonging to dif ferent trophic levels of the aquatic environme

关键词： wastewater sized likely

State-of-the-art management of dysplastic Barrett’s esophagus

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Gastroenterology Report 2022年第1期10卷 195-206页

作者： Kornpong Vantanasiri prasad G.Iyer Barrett’s Esophagus Unit Division of Gastroenterology and HepatologyMayo ClinicRochesterMNUSA

Endoscopic eradication therapy(EET)has become a standard of care for treatment of dysplastic Barrett’s esophagus(BE)and early Barrett’s neoplasia.EET mainly consists of removal of any visible lesions via endoscopic resection and eradication of all remaining Barrett’s mucosa using endoscopic ablation.Endoscopic mucosal resection and endoscopic submucosal dissection are the two available resection techniques.After complete resection of all visible lesions,it is crucial to perform endoscopic ablation to ensure complete eradication of the remaining Barrett’s segment.Endoscopic ablation can be done either with thermal techniques,including radiofrequency ablation and argon plasma coagulation,or cryotherapy techniques.The primary end point of EET is achieving complete remission of intestinal metaplasia(CRIM)to decrease the risk of dysplastic recurrence after successful EET.After CRIM is achieved,a standardized endoscopic surveillance protocol needs to be implemented for early detection of BE recurrence.

关键词： Barrett’s esophagus esophageal adenocarcinoma endoscopic eradication therapy endoscopic mucosal resection endoscopic submucosal dissection

Attention boosted autoencoder for building energy anomaly detection

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Energy and AI

Energy and AI 2023年第4期14卷 479-489页

作者： Durga prasad Pydi S.Advaith Department of Mechanical Engineering Indian Institute of Technology MadrasChennai600036India

Significant energy savings can be realised from buildings if deviations from the usual operating conditions are detected early,and appropriate measures are taken.Building anomaly detection techniques automate identifying such instances by leveraging the high dimensional data collected from the installed smart meters.Autoencoders allow for dimensionality reduction and also model the underlying data distribution.However,these models treat features as independent quantities.In contrast,the current work investigates an attention mechanism with an autoencoder to include the correlations among the features.The value addition from the attention mechanism is demonstrated by comparing the model’s reconstruction ability with an ANN-based autoencoder on synthetic datasets.The study identifies that adding an attention layer enables the encoder–decoder architecture to be robust to outliers in training data,thereby reducing the preprocessing required.Further,the model is tested on a real-world dataset,and the attention maps generated from the model are used to interpret the correlations among the features and across the time dimension,thereby establishing a human-interpretable way to understand the reconstruction from the model.

关键词： Artificial intelligence UN Sustainable Development Goals Interpretable model Multivariate time series HVAC

Choice of precipitant and calcination temperature of precursor for synthesis of NiCo_2O_4 for control of CO–CH_4 emissions from CNG vehicles

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Journal of Environmental Sciences 2018年第3期30卷 62-71页

作者： Suverna Trivedi Ram prasad Department of Chemical Engineering &Technology Indian Institute of Technology (BHU)

Compressed natural gas（CNG）is most appropriate an alternative of conventional fuel for automobiles.However,emissions of carbon-monoxide and methane from such vehicles adversely affect human health and environment.Consequently,to abate emissions from CNG vehicles,development of highly efficient and inexpensive catalysts is necessary.Thus,the present work attempts to scan the effects of precipitants（Na2CO3,KOH and urea）for nickel cobaltite（Ni Co2O4）catalysts prepared by co-precipitation from nitrate solutions and calcined in a lean CO-air mixture at 400℃.The catalysts were used for oxidation of a mixture of CO and CH4（1：1）.The catalysts were characterized by X-ray diffractometer,Brunauer–Emmett–Teller surface-area,X-ray photoelectron spectroscopy;temperature programmedreductionandScanningelectronmicroscopycoupledwith Energy-Dispersive X-Ray Spectroscopy.The Na2CO3was adjudged as the best precipitant for production of catalyst,which completely oxidized CO-CH4mixture at the lowest temperature（T（100）=350℃）.Whereas,for catalyst prepared using urea,T（100）=362℃.On the other hand the conversion of CO-CH4mixture over the catalyst synthesized by KOH limited to 97%even beyond 400℃.Further,the effect of higher calcination temperatures of 500 and600℃ was examined for the best catalyst.The total oxidation of the mixture was attained at higher temperatures of 375 and 410℃ over catalysts calcined at 500 and 600℃ respectively.Thus,the best precipitant established was Na2CO3and the optimum calcination temperature of 400℃ was found to synthesize the Ni Co2O4catalyst for the best performance in CO-CH4oxidation.

关键词： CNG vehicular emissions CO-CH4 oxidation NiG0204 Precipitants Calcinations

Herbal Medicine in Ischemic Stroke:Challenges and Prospective

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Chinese Journal of Integrative Medicine 2018年第4期24卷 243-246页

作者： Bhakta prasad Gaire Department of Herbal Pharmacology College of Korean MedicineKyung Hee University

Herbal medicines, mainly of plant source, are invaluable source for the discovery of new therapeutic agents for all sorts of human ailments. The complex pathogenesis of stroke and multifactorial effect of herbal medicine and their active constituents may suggest the promising future of natural medicine for stroke treatment. Anti-oxidant, anti-inflammatory, anti-apoptotic, neuroprotective and vascular protective effect of herbal medicines are believed to be efficacious in stroke treatment. Herbs typically have fewer reported side effects than allopathic medicine, and may be safer to use over longer period of time. Herbal medicines are believed to be more effective for the longstanding health complaints, such as stroke. Several medicinal plants and their active constituents show the promising results in laboratory research. However failure in transformation of laboratory animal research to the clinical trials has created huge challenge for the use of herbal medicine in stroke. Until and unless scientifically comprehensive evidence of the efficacy and safety of herbal medicine in ischemic stroke patients is available, efforts should be made to continue implementing treatment strategies of proven effectiveness. More consideration should be paid to natural compounds that can have extensive therapeutic time windows, perfect pharmacological targets with few side effects. Herbal medicine has excellent prospective for the treatment of ischemic stroke, but a lot of effort should be invested to transform the success of animal research to human use.

关键词： herbal medicine stroke pathogenesis medicinal plant active constituent stroke therapy