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On stress-induced voltage hysteresis in lithium ion batteries:Impacts of surface effects and interparticle compression

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Science China(Technological Sciences) 2019年第8期62卷 1357-1364页

作者： JIN ChuanJian LI HaoLiang SONG YiCheng LU Bo SOH A. k. ZHANG JunQian Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Department of Mechanics Shanghai University Shanghai 200444 China Shanghai key Laboratory of Mechanics in Energy Engineering Shanghai University Shanghai 200444 China School of Engineering Monash University Sunway Campus Bandar Sunday 47500 Malaysia

Application of silicon in high capacity electrodes of lithium ion battery suffers from stress effects and, in turn, affects voltage performance of battery. This paper established a reaction-diffusion-stress coupled model and investigated the stress induced voltage hysteresis with consideration of diffusion induced stress, surface effects and interparticle compression. It was found stress and stress induced voltage hysteresis depended on particle size. In big particles, diffusion induced stress is dominant and leads to significant hysteresis in both stress and voltage, indicating energy dissipation due to stress effects. In small particles, e.g.,radius of dozens nanometers, diffusion induced stress was negligible while surface effects played dominant role, leading to nearly vanished voltage hysteresis shifting away from equilibrium potential. According to calculation, particle sizes around 100 nm are appropriate choice for electrode design as both diffusion induced stress and surface effects are insignificant. Finally,interparticle compression pushed the stress hysteresis to compressive side and led to early termination of lithiation at cut-off voltage. Denser electrode would enhance this effect. It indicated that there must be a limit of mixing ratio of silicon because higher interparticle compressive stress due to more introduced silicon would impede the battery from fully charged.

关键词： lithium ion battery voltage hysteresis stress surface effect interparticle compression

Phase modification and dielectric properties of a cullet–paper ash–kaolin clay-based ceramic

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International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 350-356页

作者： k.A.Samah M.R.Sahar M.Yusop M.F.Omar Advance Optical Material Research Group Department of Physics Faculty of Science Universiti Teknologi Malaysia

Novel ceramics from waste material made of(x) paper ash–(80-x) cullet–20 kaolin clay(10 wt% ≤ x ≤ 30 wt%) were successfully synthesized using a conventional solid-state reaction technique. Energy-dispersive X-ray analysis confirmed the presence of Si, Ca, Al, and Fe in the waste material for preparing these ceramics. The influence of the cullet content on the phase structures and the dielectric properties of these ceramics were systematically investigated. The impedance spectra were verified in the range from 1 Hz to 10 MHz at room temperature. The phase of the ceramics was found to primarily consist of wollastonite(CaSiO_3), along with minor phases of γ-dicalcium silicate(Ca_2SiO_4) and quartz(SiO_2). The sample with a cullet content of 55 wt% possessed the optimum wollastonite structure and exhibited good dielectric properties. An increase of the cullet content beyond 55 wt% resulted in a structural change from wollastonite to dicalcium silicate, a decrease in dielectric constant, and an increase in dielectric loss. All experimental results suggested that these novel ceramics from waste are applicable for electronic devices.

关键词： ceramics cullet glass paper ash wollastonite structural properties dielectric properties

Desulfurization of dibenzothiophene(DBT) by a novel strain Lysinibacillus sphaericus DMT-7 isolated from diesel contaminated soil

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Journal of Environmental Sciences 2011年第6期23卷 975-982页

作者： Ashutosh Bahuguna Madhuri k.Lily Ashok Munjal Ravindra N.Singh koushalya Dangwal Department of Biotechnology Modern Institute of Technology(MIT)DhalwalaRishikesh 249201UttarakhandIndia Department of Bioscience and Biotechnology Banasthali UniversityBanasthali 304022RajasthanIndia Department of Biochemistry S.B.S.P.G.Institute of Biomedical Sciences and ResearchBalawalaDehradun 248001UttarakhandIndia

A new bacterial strain DMT-7 capable of selectively desulfurizing dibenzothiophene（DBT） was isolated from diesel contaminated *** DMT-7 was characterized and identified as Lysinibacillus sphaericus DMT-7（NCBI GenBank Accession ***496620） using 16S rDNA gene sequence *** desulfurized product of DBT,2-hydroxybiphenyl（2HBP）,was identified and confirmed by high performance liquid chromatography analysis and gas chromatography-mass spectroscopy analysis *** desulfurization kinetics revealed that DMT-7 started desulfurization of DBT into 2HBP after the lag phase of 24 hr,exponentially increasing the accumulation of 2HBP up to 15 days leading to approximately 60% desulfurization of the ***,further growth resulted into DBT *** induced culture of DMT-7 showed shorter lag phase of 6 hr and early onset of stationary phase within 10 days for desulfurization as compared to that of non-induced culture clearly indicating the inducibility of the desulfurization pathway of *** addition,Lysinibacillus sphaericus DMT-7 also possess the ability to utilize broad range of substrates as sole source of sulfur such as benzothiophene,3,4-benzo DBT,4,6-dimethyl DBT,and 4,6-dibutyl ***,Lysinibacillus sphaericus DMT-7 could serve as model system for efficient biodesulfurization of diesel and petrol.

关键词： biodesulfurization colony forming units .dibenzothiophene high performance liquid chromatography Lysinibacillus sphaericus DMT-7

Dust Acoustic Shock Waves with Non-Thermal and Vortex-Like Ions in Dusty Plasma

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Plasma Science and Technology 2015年第4期17卷 268-275页

作者： Apul N.DEV Jnanjyoti SARMA Manoj k.DEkA Nirab C.ADHIkARY Department of Science and Humanities College of Science and Technology RUB Bhutan Department of Mathematics R. G. Baruah College Guwahati-781025 Assam India Centre of Plasma Physics Tepesia Sonapur Assam India Physical Science Divison Institute of Advanced Study in Science and Technology Vigyan Path Garchuk Guwahati-781035 Assam India

A rigorous investigation is presented on the propagation characteristics of non-linear dust acoustic（DA）waves in an unmagnetized dusty plasma system containing non-thermal and vortex-like ions and Maxwellian electrons under the effect of a fluctuating charged dust *** three-dimensional（3D）Burgers＇equation and a new form of a lower degree modified 3D Burgers＇equation with their analytical solutions are derived to study the features of shock waves in such *** effect of the population of non-thermal ions,the vortex-like ion parameter as well as the temperature ratios of ions and electrons on the evolution of shock waves in the presence of dust charge fluctuation is *** theoretical investigation might be effectively utilized to unveil the nature of many astrophysical plasma environments（Saturn＇s spokes etc.）where such plasmas are reported to have existed.

关键词： dusty plasma reductive perturbation method 3D Burgers' equation modified 3D Burgers' equation tan-hyperbolic method

Template-Based Gait Authentication Through Bayesian Thresholding

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 209-219页

作者： Ebenezer R.H.P.Isaac Susan Elias Srinivasan Rajagopalan k.S.Easwarakumar IEEE the Department of Computer Science and Engineering Indian Institute of Technology Madras the School of Electronics Engineering VIT University the Department of Physiology and Biomedical Engineering Mayo Clinic the Department of Computer Science and Engineering Anna University

While gait recognition is the mapping of a gait sequence to an identity known to the system, gait authentication refers to the problem of identifying whether a given gait sequence belongs to the claimed identity. A typical gait authentication system starts with a feature representation such as a gait template, then proceeds to extract its features, and a transformation is ultimately applied to obtain a discriminant feature set. Almost every authentication approach in literature favours the use of Euclidean distance as a threshold to mark the boundary between a legitimate subject and an impostor. This article proposes a method that uses the posterior probability of a Bayes' classifier in place of the Euclidean distance. The proposed framework is applied to template-based gait feature representations and is evaluated using the standard CASIA-B gait database. Our study experimentally demonstrates that the Bayesian posterior probability performs significantly better than the de facto Euclidean distance approach and the cosine distance which is established in research to be the current state of the art.

关键词： Bayes’ rule biometrics gait recognition linear discriminant analysis verification

Unusual switchable peroxidase-mimicking nanozyme for the determination of proteolytic biomarker

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Nano Research 2019年第3期12卷 509-516页

作者： Claire McVey Natasha Logan Nguyen T. k. Thanh Christopher Elliott Cuong Cao Institute for Global Food Security School of Biological Sciences Queens University Belfast 18-30 Malone Road Belfast BT9 5BN UK Biophysics Group Department of Physics and Astronomy University College London London WC1E 6BT UK UCL Healthcare Biomagnetic and Nanomaterials Laboratories 21 Albemarle Street London W1S 4BS UK Material and Advanced Technologies for Healthcare Queens University Belfast 18-30 Malone Road Belfast BT9 5BN UK

Detection of enzyme biomarkers originating from either bio-fluids or contaminating microorganisms is of utmost importance in clinical diagnostics and food safety. Herein, we present a simple, low-cost and easy-to-use sensing approach based on the switchable peroxidase-mimicking activity of plasmonic gold nanoparticles (AuNPs) that can catalyse for the oxidation of 3,3’,5’5-tetramethylbenzidine (TMB) for the determination of protease enzyme. The AuNP surface is modified with casein, showing dual functionalities. The first function of the coating molecule is to suppress the intrinsic peroxidase-mimicking activity of AuNPs by up to 77.1%, due to surface shielding effects. Secondly, casein also functions as recognition sites for the enzyme biomarker. In the presence of protease, the enzyme binds to and catalyses the degradation of the coating layer on the AuNP surface, resulting in the recovery of peroxidase-mimicking activity. This is shown visually in the development of a blue colored product (oxidised TMB) or spectroscopically as an increase in absorbance at 370 and 650 nm. This mechanism allows for the detection of protease at 44 ng·mL^-1 in 90 min. The nanosensor circumvents issues associated with current methods of detection in terms of ease of use, compatibility with point-of-care testing, low-cost production and short analysis time. The sensing approach has also been applied for the detection of protease spiked in ultra-heat treated (UHT) milk and synthetic human urine samples at a limit of detection of 490 and 176 ng·mL^-1, respectively, showing great potential in clinical diagnostics, food safety and quality control.

关键词： gold nano particles peroxidase-mimicking nanozyme enzyme detection biomarkers

Surface chemistry of carbon nanoparticles functionally select their uptake in various stages of cancer cells

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Nano Research 2017年第10期10卷 3269-3284页

作者： Indrajit Srivastava Santosh k. Misra Fatemeh Ostadhossein Enrique Daza Jasleena Singh Dipanjan Pan Department of Bioengineering University of Illinois Urbana-Champaign Urbana Illinois 61801 USA Biomedical Research Center Carle Foundation Hospital Urbana Illinois 61801 USA Department of Materials Science and Beckman Institute University of illinois Urbana-Champaign Urbana Illinois 61801 USA

Relationship of the surface physicochemical characteristics of nanoparticles with their interactions with biological entities may provide critical information for nanomedicinal application. Here, we report the systematic synthesis of sub-50 nm carbon nanoparticles （CNP） presenting neutral, anionic, and cationic surface functionalities. A subset of CNPs with -10, 20, and 40 nm hydrodynamic sizes were synthesized with neutral surface headgroups. For the first time, the cellular internalization of these CNPs was systematically quantified in various stages of breast cancer cells （early, late, and metastatic）, thereby providing a parametric assessment of charge and size effects. Distinct activities were observed when these systems interacted with cancer cells in various stages. Our results indicated that metastatic breast cancer could be targeted by a nanosystem presenting anionic phosphate groups. On the contrary, for patients in late stage of cancer, drugs could be delivered with sulfonate functionalized carbon nano- particles, which have higher probability of intracellular transport. This study will facilitate the better understanding of nanoparticle-biological entity interaction, and the integration of this knowledge with pathophysiology would promote the engineering of nanomedicine with superior likelihoods of crossing the endocytic ＂barrier＂ for drug delivery inside cancerous cells.

关键词： personalized medicine endocytosis surface charge size carbon nanoparticles

Transport and humification of dissolved organic matter within a semi-arid floodplain

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Journal of Environmental Sciences 2017年第7期29卷 24-32页

作者： Wenming Dong Jiamin Wan Tetsu k.Tokunaga Benjamin Gilbert kenneth H.Williams Earth and Environment Sciences Area Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

In order to understand the transport and humification processes of dissolved organic matter（DOM） within sediments of a semi-arid floodplain at Rifle,Colorado,fluorescence excitation–emission matrix（EEM） spectroscopy,humification index（HIX） and specific UV absorbance（SUVA） at 254 nm were applied for characterizing depth and seasonal variations of DOM *** revealed that late spring snowmelt leached relatively fresh DOM from plant residue and soil organic matter down into the deeper vadose zone（VZ）.More humified DOM is preferentially adsorbed by upper VZ sediments,while non-or lesshumified DOM was transported into the deeper ***,DOM at all depths undergoes rapid biological humification process evidenced by the products of microbial by-product-like（i.e.,tyrosine-like and tryptophan-like） matter in late spring and early summer,particularly in the deeper VZ,resulting in more humified DOM（e.g.,fulvic-acid-like and humic-acid-like substances） at the end of *** indicates that DOM transport is dominated by spring snowmelt,and DOM humification is controlled by microbial degradation,with seasonal *** is expected that these relatively simple spectroscopic measurements（e.g.,EEM spectroscopy,HIX and SUVA） applied to depth-and temporally-distributed pore-water samples can provide useful insights into transport and humification of DOM in other subsurface environments as well.

关键词： Dissolved organic matter Transport Humification Semi-arid Fluorescence excitation-emission matrix

Rilmenidine prevents blood pressure increase in rats with compromised nitric oxide production

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Acta Pharmacologica Sinica 2004年第12期25卷 74-80页

作者： Mria GEROV,Jozef TRk,Ol’ga PECHV,Jana MATUkOV SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute of Pathophysiology Medical School Comenius University Bratislava Slovak Republic Now in Center for Blood Research and Department of Pathology Harvard MedicalSchool Boston Institute ofNormal and Pathological Physiology USA. SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology

AIM: To search tools of high blood pressure in the model of nitric oxide (NO)-defective hypertension, and the study focused on the effect of rilmenidine, agonist of imidazoline receptors, which was suggested to modulate central sympathetic outflow. METHODS: Three experimental groups, each consisting of 7 rats, were used: (I) rats with inhibition of NO synthase (NOS) by NG-nitro-L-arginine methyl ester (L-NAME) 40 mg·kg-1·d-1 for 4 weeks in drinking water, (II) rats with inhibited NOS as in group I , plus agonist of imidazoline receptors rilmenidine 3 mg·kg-1·d-1 for 4weeks by gavage, and(III) control rats. Systolic blood pressure wasmeasured weekly noninvasively. At the end of experiment aortic ring isometric tension was followed, NOS expression (aorta, left ventricle), and NOS activity (left ventricle and brain) were determined. RESULTS: In the group I systolic blood pressure in- creased significantly, aortic ring relaxation to acetylcholine was significantly attenuated. Rilmenidine administered simultaneously with L-NAME (group II) prevented the increase of blood pressure which did not differ significantly from control values; aortic ring relaxation to acetylcholine did not differ from control. No change in NOS expres- sion (aorta and left ventricle) was found in groups I and II. Significant decline in NOS activity (left ventricle and brain) wasfound in groups I and II. CONCLUSION: Rilmenidinehas aremarkable role inNO-defective hypertension, possibly by inhibiting central sympathetic outflow and by affecting receptors in vascular smooth muscle also. The prime cause of hypertension in this experimental model - the compromised production of NO due to inhibition of NOS - was not affected by rilmenidine.

关键词： NO deficiency hypertension imidazoline receptor nitric-oxide synthase sympathetic activity