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Optimizing extractants selection for efficient separation of phenols and nitrogen-containing heteroaromatics using hydrogen bond interaction strategies

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Chinese Journal of Chemical Engineering 2024年第4期68卷 43-52页

作者： Pengzhi Bei Rui Zhang Jie Feng Antony rajendran Wenying Li State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China Department of Chemistry Mepco Schlenk Engineering College(Autonomous)Sivakasi 626005India

Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific sites for hydrogen bond-based separation has been *** environmentally friendly solvents are known for their ability to form hydrogen bonds with heteroatoms,a key aspect in separation *** quantified the hydrogen bond interaction energy to reach the threshold energy for efficient O-and n-heteroaromatics *** article provides an in-depth study of the structural nuances of different hydrogen bonding sites and their affinity properties while conducting a comparative evaluation of the separation efficiency of ionic liquids and deep eutectic solvents from a thermodynamic *** showed that phenols with dual hydrogen bonding recognition sites were easier to separate than nitrogen-containing *** ionic liquids were more suitable for the extraction of nonbasic nitrogen-containing heteroaromatics,and quaternary ammonium salts-based deep eutectic solvents are more effective for phenols and basic nitrogen-containing heteroaromatics,which was confirmed by Fourier transform infrared spectroscopy and empirical ***,this study provides a theoretical basis for the strategy design and selection of extractants for the efficient separation of O-and n-containing aromatic compounds.

关键词： Deep eutectic solvents Hydrogen bond Ionic liquids Separation Solvents Structural characteristics

A passive,reusable,and resonating wearable sensing system for ondemand,non-invasive,and wireless molecular stress biomarker detection

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nano Research 2024年第8期17卷 7542-7556页

作者： Shingirirai Chakoma Xiaochang Pei Huiting Qin Anita Ghandehari Sahar najafiKhoshnoo Jerome rajendran Rahim Esfandyarpour Department of Electrical Engineering and Computer Science University of CaliforniaIrvineCA 92697USA Laboratory for Integrated nano BioElectronics Innovation The Henry Samueli School of EngineeringUniversity of CaliforniaIrvineCA 92697USA Henry Samueli School of Engineering University of CaliforniaIrvineCA 92697USA

The significant impact of stress on health necessitates accurate assessment methods,where traditional questionnaires lack reliability and *** advancements like wearables with electrocardiogram(ECG)and galvanic skin response(GSR)sensors face accuracy and artifact *** biosensors detecting cortisol,a critical stress hormone,present a promising ***,existing cortisol assays,requiring saliva,urine,or blood,are complex,expensive,and unsuitable for continuous *** study introduces a passive,molecularly imprinted polymer-radio-frequency(mIP-RF)wearable sensing system for real-time,non-invasive sweat cortisol *** system is wireless,flexible,battery-free,reusable,environmentally stable,and designed for long-term monitoring,using an inductance-capacitance *** transducer translates cortisol concentrations into resonant frequency shifts with high sensitivity(~160 kHz/(log(μm)))across a physiological range of 0.025–1μ*** with near-field communication(nFC)for wireless and battery-free operation,and threedimensional(3D)-printed microfluidic channel for in-situ sweat collection,it enables daily activity cortisol level *** of cortisol circadian rhythm through morning and evening measurements demonstrates its effectiveness in tracking and monitoring sweat cortisol levels.A 28-day stability test and the use of cost-effective 3D nanomaterials printing enhance its economic viability and *** innovation paves the way for a new era in realistic,on-demand health monitoring outside the laboratory,leveraging wearable technology for molecular stress biomarker detection.

关键词： cortisol wearable flexible sensors three-dimensional(3D)nanomaterials printing reusable environmentally stable

Control of nozzle Flow Using Rectangular Ribs at Sonic and Supersonic mach numbers

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Fluid Dynamics & materials Processing 2024年第8期20卷 1847-1866页

作者： Vigneshvaran Sethuraman Parvathy rajendran Sher Afghan Khan Abdul Aabid muneer Baig School of Aerospace Engineering Universiti Sains MalaysiaEngineering CampusNibong TebalPulau Pinang14300Malaysia Department of mechanical and Aerospace Engineering Faculty of EngineeringInternational Islamic University MalaysiaKuala Lumpur53100Malaysia Department of Engineering management College of EngineeringPrince Sultan UniversityP.O.Box 66833Riyadh11586Saudi Arabia

This study deals with base pressure management in a duct for various values of the mach number(m),namely,mach number corresponding to sonic and four supersonic *** addition to the mach number,the nozzle pressure ratio(nPR),the area ratio,the rib dimension,and the duct length are influential *** following specific values are examined at m=1,1.36,1.64,and 2,and nPRs between 1.5 and *** base pressure is determined by positioning ribs of varying heights at predetermined intervals throughout the length of the square *** the level of expansion is varied,it is seen that the base pressure initially drops for overexpanded flows and increases for under-expanded *** ribs are present,the flow field in the duct and pressure inside the duct fluctuate as the base pressure ***-expanded flows can achieve a base pressure value that is suitably high without experiencing excessive changes in the duct flow in terms of static pressure if a rib height around 10%of the duct height close to the nozzle exit is *** rib passive control does not negatively affect the duct’s flow field.

关键词： Base pressure internal flows ribs suddenly expanded flow wall pressure

magnetic,dielectric and electrical modulus of Ce^(3+) doped cobalt-magnesium ferrite nanoparticles

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Journal of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： n.m.Basfer Hanaa Almaghamsi Department of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Department College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In this work,the magnetic,dielectric properties and electric modulus of Ce^(3+) substituted cobaltmagnesium(Co_(0.7)mg_(0.3)Ce_(x)Fe_(2-x)O_4)(labeled as CmCF) ferrite nanoparticles were investigated in *** magnetization decreases from 50.05 to 34.87 emu/g for further substituting Ce^(3+) ***,coercivity increases from 738.22 Gs for the CmCFO sample to 912.10 Gs for the CmCF2 sample,then decreases monotonically to 762.1 Gs for the CmCF5 *** cerium content and particle size play important roles in controlling the magnetization and coercivity of the CmCF *** CmCF nanoferrites are suitable for microwave applications since their high-frequency response ranges from 7.72 to 11.07 *** CmCF nanoferrites' dielectric parameter dispersion exhibits normal *** pristine Co-mg nanoferrite only has ε' value of 28.25,but the nanoferrite mCmF2 has ε' value of365.03,with an enhancing ratio of 1192%.The conduction mechanism of the mCmF nanoferrites was determined by fitting the σ_(ac) results via the Jonscher power *** 653 K,large polaron tunnelling is thought to be responsible for this conduction process,which is followed by electron barrier hopping at higher ***-Cole diagrams at different temperatures,assuring the contributions of the grains and their boundaries at lower temperatures(653 K) and only the grains at higher *** on our results,the CmCF nanoferrites hold magnetic and semiconducting nature,which can be used in magnetic devices and dielectrics in lower-frequencies or conductors in higher-frequencies.

关键词： nanoferrites Rare earth ions magnetic properties Dielectric parameters Impedance spectroscopy

EDSUCh:A robust ensemble data summarization method for effective medical diagnosis

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Digital Communications and networks 2024年第1期10卷 182-189页

作者： mohiuddin Ahmed A.n.m.Bazlur Rashid School of Science Edith Cowan UniversityPerthAustralia

Identifying rare patterns for medical diagnosis is a challenging task due to heterogeneity and the volume of *** summarization can create a concise version of the original data that can be used for effective *** this paper,we propose an ensemble summarization method that combines clustering and sampling to create a summary of the original data to ensure the inclusion of rare *** the best of our knowledge,there has been no such technique available to augment the performance of anomaly detection techniques and simultaneously increase the efficiency of medical *** performance of popular anomaly detection algorithms increases significantly in terms of accuracy and computational complexity when the summaries are ***,the medical diagnosis becomes more effective,and our experimental results reflect that the combination of the proposed summarization scheme and all underlying algorithms used in this paper outperforms the most popular anomaly detection techniques.

关键词： Data summarization Ensemble medical diagnosis Sampling

A FLEXIBLE OBJECTIVE-COnSTRAInT APPROACH AnD A nEW ALGORITHm FOR COnSTRUCTInG THE PARETO FROnT OF mULTIOBJECTIVE OPTImIZATIOn PROBLEmS

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Acta mathematica Scientia 2024年第2期44卷 702-720页

作者： n.HOSEInPOOR m.GHAZnAVI Faculty of mathematical Sciences Shahrood University of TechnologyShahroodIran

In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems.

关键词： multiobjective optimization Pareto front scalarization objective-constraint approach proper efficient solution

Predicting effects of tunnel throttling of annular freeway vehicular flow by a continuum model

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 733-746页

作者： Zhongmin Huang m.n.Smirnova n.n.Smirnov Zuojin Zhu Faculty of Engineering Science University of Science and Technology of China Institute of Plasma Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Faculty of mechanics and mathematics Lomonosov Moscow State University

Fluid flow throttling is common in industrial and building services engineering. Similar tunnel throttling of vehicular flow is caused by the abrupt number reduction of roadway lane, as the tunnel has a lower lane number than in the roadway normal segment. To predict the effects of tunnel throttling of annular freeway vehicular flow, a three-lane continuum model is developed. Lane Ⅲ of the tunnel is completely blocked due to the need of tunnel rehabilitation, etc. There exists mandatory net lane-changing rate from lane Ⅲ to lane Ⅱ just upstream of the tunnel entrance, which is described by a model of random number generated through a golden section analysis. The net-changing rate between adjacent lanes is modeled using a lane-changing time expressed explicitly in algebraic form. This paper assumes that the annular freeway has a total length of 100 km, a two-lane tunnel of length 2 km with a speed limit of 80 km/h. The free flow speeds on lanes Ⅰ, Ⅱ and Ⅲ are assumed to be 110, 100 and 90 km/h respectively. Based on the three-lane continuum model, numerical simulations of vehicular flows on the annular freeway with such a tunnel are conducted with a reliable numerical method of 3rd-order accuracy. numerical results reveal that the vehicular flow has a smaller threshold of traffic jam formation in comparison with the case without tunnel throttling. Vehicle fuel consumption can be estimated by interpolation with time averaged grid traffic speed and an assumed curve of vehicle performance. The vehicle fuel consumption is lane number dependent, distributes with initial density concavely, ranging from 5.56 to 8.00 L. Tunnel throttling leads to an earlier traffic jam formation in comparison with the case without tunnel throttling.

关键词： Effects of tunnel throttling Vehicle fuel consumption Travel time Threshold of traffic jam formation Continuum model

Inclusion of CoTiO_(3) to ameliorate the re/dehydrogenation properties of the mg–na–Al system

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Journal of magnesium and Alloys 2024年第3期12卷 1215-1226页

作者： n.A.Ali n.Y.Yusnizam n.A.Sazelee Sami-ullah Rather Haizhen Liu m.Ismail Energy Storage Research Group Faculty of Ocean Engineering TechnologyUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Department of Chemical and materials Engineering King Abdulaziz UniversityP.O.Box80204Jeddah 21589Saudi Arabia Guangxi novel Battery materials Research Center of Engineering Technology School of Physical Science and TechnologyGuangxi UniversityNanning 530004China State Key Laboratory of Featured metal materials and Life-Cycle Safety for Composite Structures Nanning 530004China

For the first time,the mgH_(2)–naAlH_(4)(ratio 4:1)destabilized system with CoTiO_(3) addition has been *** CoTiO_(3)-doped mgH_(2)–naAlH_(4) sample begins to dehydrogenate at 130℃,which is declined by 40℃ compared to the undoped mgH_(2)–naAlH_(4).moreover,the de/rehydrogenation kinetics characteristics of the CoTiO_(3)-doped mgH_(2)–naAlH_(4) were greatly *** the inclusion of CoTiO_(3),the mgH_(2)–naAlH_(4) composite absorbed 5.2 wt.%H_(2),higher than undoped mgH_(2)–naAlH_(4).In the context of dehydrogenation,the CoTiO_(3)-doped mgH_(2)–naAlH_(4) sample desorbed 2.6 wt.%H_(2),almost doubled compared to the amount of hydrogen desorbed from the undoped mgH_(2)–naAlH_(4) *** activation energy obtained by the Kissinger analysis for mgH_(2) decomposition was significantly lower by 35.9 kJ/mol than the undoped mgH_(2)–naAlH_(4) *** reaction mechanism demonstrated that new phases of mgCo and AlTi_(3) were generated in situ during the heating process and are likely to play a substantial catalytic function and be useful in ameliorating the de/rehydrogenation properties of the destabilized mgH_(2)–naAlH_(4) system with the inclusion of CoTiO_(3).

关键词： Destabilize system magnesium hydride Sodium alanate Hydrogen storage Additive.

Effect of cold-working on corrosion induced damage in lug joints

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Defence Technology（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath m.n Chikmath L. murthy H. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

Lug joints are preferred joineries for transferring heavy loads to parent components in aerospace *** experience corrosion due to environmental conditions,improper surface finishes and rubbing displacement between the pin and *** causes damage of different sizes and shapes near the *** degradation due to corrosion-induced damage is modelled as a through-pit at one of the identified critical locations through stress *** effect of this pit on fatigue crack initiation life is ***-hole is pre-stressed by cold-working and the benefits of inducing plastic wake on the intended performance of the lug joint during the damages due to corrosion are brought out and compared with non-cold-worked *** analysis is performed on this lug joint with *** results obtained highlight the benefits of cold-working and the methodology can be extended to damage growth and analyse the effect of surface treatments for better structural integrity of components of aerospace vehicles.

关键词： Lug joint Corrosion Crack initiation Cold-working Structural integrity