检索结果-南通市图书馆

Particuology 2024年第8期91卷 260-267页

作者： tom Lang Jens Bartsch Laboratory of Solids Process Engineering Department of Biochemical and Chemical EngineeringTU Dortmund University44227DortmundGermany

In comparison to the established twin-screw machines,the application of a planetary roller granulator for continuous operation of melt granulation is a promising alternative based on the unique process *** initial study focused on the material transport during processing as a key driver for the overall ***,the impact of direct process parameters on the residence time distribution was the main *** investigations are complemented in this study by considering the free processing volume,which is defined by the number of planetary spindles applied within a *** impact on the processing conditions is evaluated with respect to the process setting in terms of feed rate and rotation *** results highlight the potential of altering the underlying transport function in planetary roller melt granulation(PRMG)via the investigated direct process and equipment *** impact of the feed rate is lower in comparison,while a higher rotation speed as well as a higher free processing volume promote material ***,a normalization of the determined residence time distribution(RTD)model data was feasible with respect to the process settings and the number of applied planetary spindles in the processing *** demonstrates the key role of the free processing volume in the fundamental mechanisms of material transport and mixing during PRMG.

关键词： Continuous manufacturing Melt granulation Planetaryroller granulator Quality-by-Design Residence time Material mixing

Liquid superlubricity of lubricants containing hydroxyl groups and their aqueous solution under rolling/sliding conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2024年第1期12卷 164-173页

作者： tomáš POLÁČEK Petr ŠPERKA Ivan KŘUPKA Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic

Macroscale rolling/sliding conditions are in the superlubricity,a little-studied topic so *** purpose of this paper is to examine the formation of elastohydrodynamic lubrication(EHL)films by water-based lubricants(glycerol and polyethylene glycol(PEG)),providing superlubricous *** were carried out on an optical ball-on-disc tribometer under rolling/sliding *** film thickness was measured by the thin film colorimetric interferometry,and the viscosity of liquids was measured by rotational and high-pressure falling body *** results show that tribochemical reactions are not the mandatory reason for friction to reach the superlubricity level when using the water-based *** studied liquids themselves are almost *** the addition of water,the signs of shear thinning behavior disappear even *** conditions for this type of lubricant can be predicted using the known Hamrock–Dowson *** anomaly in the thickness of the lubricants was observed as an abrupt change at certain *** more PEG there is in the lubricant,the higher the thickness at the beginning of the jump.

关键词： macroscale superlubricity super low traction water-based lubricants elastohydrodynamic lubrication(EHL) film thickness

Predicting the coefficient of friction in a sliding contact by applying machine learning to acoustic emission data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2024年第6期12卷 1299-1321页

作者： Robert GUTIERREZ Tianshi FANG Robert MAINWARING tom REDDYHOFF Tribology Group Department of Mechanical EngineeringImperial College LondonExhibition RoadLondon SW72AZUK Shell Global Solutions(US)Inc.Shell Technology Center Houston 3333 Highway 6 SouthHoustonTX 77082USA Shell International Petroleum Company Limited Shell CentreYork RoadLondon SE17NAUK

It is increasingly important to monitor sliding interfaces within machines,since this is where both energy is lost,and failures *** emission(AE)techniques offer a way to monitor contacts remotely without requiring transparent or electrically conductive ***,acoustic data from sliding contacts is notoriously complex and difficult to ***,we simultaneously measure coefficient of friction(with a conventional force transducer)and acoustic emission(with a piezoelectric sensor and high acquisition rate digitizer)produced by a steel‒steel rubbing *** data is then used to train machine learning(ML)algorithms(e.g.,Gaussian process regression(GPR)and support vector machine(SVM))to correlated acoustic emission with *** training requires the dense AE data to first be reduced in size and a range of processing techniques are assessed for this(e.g.,down-sampling,averaging,fast Fourier transforms(FFTs),histograms).Next,fresh,unseen AE data is given to the trained model and the resulting friction predictions are compared with the directly measured *** is excellent agreement between the measured and predicted friction when the GPR model is used on AE histogram data,with root mean square(RMS)errors as low as 0.03 and Pearson correlation coefficients reaching ***,predictions remain accurate despite changes in test conditions such as normal load,reciprocating frequency,and stroke *** paves the way for remote,acoustic measurements of friction in inaccessible locations within machinery to increase mechanical efficiency and avoid costly failure/needless maintenance.

关键词： acoustic emission condition monitoring friction machine learning Gaussian process regression support vector machine

FPGA Accelerators for Computing Interatomic Potential-Based Molecular Dynamics Simulation for Gold Nanoparticles:Exploring Different Communication Protocols

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第9期80卷 3803-3818页

作者： Ankitkumar patel Srivathsan Vasudevan Satya Bulusu Department of Electrical Engineering Indian Institute of Technology IndoreIndore453552India Department of Chemistry Indian Institute of Technology IndoreIndore453552India

Molecular Dynamics(MD)simulation for computing Interatomic Potential(IAP)is a very important High-Performance Computing(HPC)*** simulation on particles of experimental relevance takes huge computation time,despite using an expensive high-end *** computing,a combination of the Field Programmable Gate Array(FPGA)and a computer,is proposed as a solution to compute MD simulation *** such heterogeneous computation,communication between FPGA and Computer is *** such MD simulation,explained in the paper,is the(Artificial Neural Network)ANN-based IAP computation of gold(Au_(147)&Au_(309))*** simulation calculates the forces between atoms and the total energy of the chemical *** work proposes the novel design and implementation of an ANN IAP-based MD simulation for Au_(147)&Au_(309) using communication protocols,such as Universal Asynchronous Receiver-Transmitter(UART)and Ethernet,for communication between the FPGA and the host *** improve the latency of MD simulation through heterogeneous computing,Universal Asynchronous Receiver-Transmitter(UART)and Ethernet communication protocols were explored to conduct MD simulation of 50,000 *** this study,computation times of 17.54 and 18.70 h were achieved with UART and Ethernet,respectively,compared to the conventional server time of 29 h for Au_(147) *** results pave the way for the development of a Lab-on-a-chip application.

关键词： Ethernet hardware accelerator heterogeneous computing interatomic potential(IAP) MDsimulation peripheral component interconnect express(PCIe) UART

Optimization of gas lift system for well performance improvement in Asmari formation:A techno-economic perspective

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Research 2024年第1期9卷 115-124页

作者： Hari Sreenivasan Jash patel Dev Jain Setu patel Isaac Wilson Shanker Krishna Drilling Cementing&Stimulation(DCS)Research CentreDepartment of Petroleum EngineeringSchool of Energy Technology(SoET)Pandit Deendayal Energy University(PDEU)Knowledge CorridorRaysanGandhinagarGujarat382426India

Well productivity in the Asmari carbonate formation of southwest Iran has decreased in recent years as a result of production *** production rate must be maintained below 1500 STB/day to prevent water *** this study,a gas lift well is modeled using data from one of the producing wells of this *** analysis is performed using lift-gas injection rates and wellhead pressures at different reservoir pressures and water cut conditions to optimize *** aspects are considered to optimize the artificial gas injection rates at different tubing head pressures and water cut *** the lift-gas injection rate from 0.4 MMscf/day to 1 MMscf/day enhances the oil production rate by 37.71%and 43.89%for 10%and 30%water cut conditions,*** injection rates of 5.2 MMscf/day and 5.4 MMscf/day are determined to be economically optimal for 30%water cut with tubing head pressures of 260 psig and 270 psig,respectively.

关键词： Production enhancement Artificial lift Gas lift Asmari carbonate formation Techno-economic analysis Well productivity

Predictive active control of building structures using LQR and artificial intelligence

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2024年第2期23卷 489-502页

作者： Nirmal S.Mehta Vishisht Bhaiya K.A.patel Ehsan Noroozinejad Farsangi Department of Civil Engineering SVNIT SuratGujarat 395007India Urban Transformations Research Centre Western Sydney UniversityNSWAustralia

This study presents a neural network-based model for predicting linear quadratic regulator(LQR)weighting matrices for achieving a target response *** on the expected weighting matrices,the LQR algorithm is used to determine the various responses of the *** responses are determined by numerically analyzing the governing equation of motion using the state-space *** training a neural network,four input parameters are considered:the time history of the ground motion,the percentage reduction in lateral displacement,lateral velocity,and lateral acceleration,Output parameters are LQR weighting *** study the effectiveness of an LQR-based neural network(LQRNN),the actual percentage reduction in the responses obtained from using LQRNN is compared with the target percentage ***,to investigate the efficacy of an active control system using LQRNN,the controlled responses of a system are compared to the corresponding uncontrolled *** trained neural network effectively predicts weighting parameters that can provide a percentage reduction in displacement,velocity,and acceleration close to the target percentage *** on the simulation study,it can be concluded that significant response reductions are observed in the active-controlled system using ***,the LQRNN algorithm can replace conventional LQR control with the use of an active control system.

关键词： active control system linear quadratic regulator artificial neural networks state-space approach response effectiveness factor resilience

Colorimetric Sensor for Detection of Tabun Mimic Diethyl Cyanophosphonate

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Analysis and Testing 2024年第3期8卷 374-384页

作者： Madhu Bala Dheeraj Pandey Nikita patel Sheetal Yadav Abha Sharma Department of Medicinal Chemistry National Institute of Pharmaceutical Education and Research RaebareliTransit Campus

Herein,a colorimetric chemosensor （probe 7） was designed and synthesized for sensing diethyl cyanophosphonate （DCNP）,a Tabun nerve agent *** sensitive,selective,fast response and photostable probe 7 in dimethylsulfoxide （DMSO）responded to DCNP at low concentrations with visual naked eye color change from pink to pale yellow and displayed unresponsive behaviour against various interferences except for copper ions,which can be di?erentiated by adding ethylene diamine where the yellow color persisted in the case of DCNP but turned to pink in the case of copper ***,the yellow aqueous solution of probe 7 at pH 10 and 12 turned colorless against the response of *** limit of detection（LOD） of probe 7 was found to be 50 nmol/L in an aqueous basic solution at pH 10 for the detection of *** formation of the cyclized product was elucidated by1H and31P NMR nuclear magnetic resonance (1H NMR,31P NMR),Fourier transform infrared spectroscopy （FTIR）,and high-resolution mass spectrometry （HRMS） ***?lter paper and silica plate loaded with probe 7 were fabricated for real-time and on-site detection of DCNP.

关键词： Chemosensor Colorimetric Fluorescence Tabun mimic

Hepatocellular carcinoma presenting as an extrahepatic mass:A case report and review of literature

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第5期16卷 2241-2252页

作者： Wei Kelly Wu Krutika patel Chandrasekhar Padmanabhan Kamran Idrees Department of Surgery Vanderbilt University Medical CenterNashvilleTN 37232United States Department of Pathology Microbiology and ImmunologyVanderbilt University Medical CenterNashvilleTN 37232United States Division of Surgical Oncology and Endocrine Surgery Department of SurgeryVanderbilt University Medical CenterNashvilleTN 37232United States

BACKGROUND Hepatocellular carcinoma(HCC)is a primary liver tumor generally diagnosed based on radiographic *** disease is typically associated with increased tumor diameter,multifocality,and vascular *** report a case of a patient who presented with extrahepatic HCC metastasis to a portocaval lymph node with occult hepatic primary on computed tomography(CT).We review the literature for cases of extrahepatic HCC presentation without known hepatic lesions and discuss strategies to differentiate between metastatic and ectopic *** SUMMARY A 67-year-old male with remotely treated hepatis C was referred for evaluation of an enlarging portocaval,mixed cystic-solid *** CT evaluations demonstrated steatosis,but no cirrhosis or liver *** ultrasound demonstrated a normal-appearing pancreas,biliary tree,and *** needle aspiration yielded atypical *** differential diagnosis included duodenal or pancreatic cyst,lymphoproliferative cyst,stromal or mesenchymal lesions,nodal involvement from gastrointestinal or hematologic malignancy,or duodenal gastrointestinal stromal *** review by a multidisciplinary tumor board,the patient underwent open surgical resection of a 5.2 cm×5.5 cm retroperitoneal mass with pathology consistent with moderately-differentiated *** resonance imaging(MRI)subsequently demonstrated a 1.2 cm segment VIII hepatic lesion with late arterial enhancement,fatty sparing,and intrinsic T1 *** fetoprotein was 23.3 ng/*** patient was diagnosed with HCC with portocaval nodal ***:We surveyed the literature for HCC presenting as extrahepatic masses without history of concurrent or prior intrahepatic *** identified 18 cases of extrahepatic HCC ultimately found to represent metastatic lesions,and 30 cases of extrahepatic HCC found to be primary,ectopic *** Hepatocellular carcinoma can seldomly present with extrahepatic metastasis in the setting of

关键词： Extrahepatic Metastasis Portocaval Lymph node Case report

Design,optimization,and characterization of an in-situ pore-forming system for controlled delivery of paliperidone

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Medicine in Novel Technology and Devices 2024年第1期21卷 71-79页

作者： Priya Pate Bhumi Ladani Gayatri patel Ramanbhai patel College of Pharmacy Charotar University of Science and TechnologyCHARUSAT–CampusChanga388421AnandGujaratIndia

The purpose of the current investigation was to develop a pharmaceutical equivalent osmotic drug delivery formulation of Paliperidone(PLD)in the form of controlled porosity osmotic pump tablets(CPOT)in order to keep the drug's steady state concentration in the *** helps to achieve the greatest therapeutic benefit with the fewest side *** the purpose of identifying various formulation attributes,preliminary trials were *** design was used to study the influence of seven input factors namely drug to polymer ratio,polymer 1(HPMC K100 M)to polymer 2(HPMC K15M),drug to total osmogens,coating level,amount of pore former,concentration of ethyl cellulose and amount of plasticizer on dependent variable similarity factor(f2).Utilizing the Minitab 17,data analysis was *** similarity factor(f2)was computed using the osmotic tablet reference product INVEGA®.The findings demonstrate that each of the seven independent variables significantly affects the similarity *** optimized batch,both core and coated tablets showed acceptable pharmaco-technical *** release profile of the optimized batch tablets was found to be similar to that of reference product with good zero-order release *** release was observed through the channels formed by in-situ pores on tablet surface performed using *** the results it can be concluded that prepared CPOT of PLD was found pharmaceutical equivalent with commercial product which is cost effective and fully compliance with cGMP.

关键词： Controlled release pH-independent release Similarity factor Pharmaceutical equivalent Reference product

Granger causal representation learning for groups of time series

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第5期67卷 56-68页

作者： Ruichu CAI Yunjin WU Xiaokai HUANG Wei CHEN tom Z.J.FU Zhifeng HAO School of Computer Science Guangdong University of Technology Peng Cheng Laboratory College of Science Shantou University

Discovering causality from multivariate time series is an important but challenging *** existing methods focus on estimating the Granger causal structures among multivariate time series,while ignoring the prior knowledge of these time series, e.g., the group of the time series. Focusing on discovering the Granger causal structures among groups of time series, we propose a Granger causal representation learning method to solve this problem. First, we use the multiset canonical correlation analysis method to learn the Granger causal representation of each group of time series. Then, we model the Granger causal relationships among the learned Granger causal representations using a recurrent neural network with temporal information. Finally, we formulate the above two stages into one unified optimization problem, which is efficiently solved using the augmented Lagrangian method. We conduct extensive experiments on synthetic and real-world datasets to validate the correctness and effectiveness of the proposed method.

关键词： Granger causal discovery Granger causal representation learning time series data recurrent neural network multiset canonical correlation analysis