检索结果-南通市图书馆

Journal of Bionic Engineering 2018年第5期15卷 820-826页

作者： Flavio Moreira Anthony Abundis michael aguirre Justin Castillo Pranav A. Bhounsule Robotics and Motion Laboratory Department of Mechanical Engineering The University of Texas at San Antonio One UTSA Circle San Antonio rX78249 USA

We have created an inchworm robot capable of the two-anchor crawl gait on level ground and inclined plane. The main novelty is in the design of the inchworm：（1） three-part body that is 3D printed and actuated by two servo motors to allow a looping and lengthening action, （2） passive friction pads to anchor the feet, each of which may be disengaged using a servo motor actuated lever arm, and （3） modular body and electronics. The robot is about 2 feet （61 cm） in length, has a mass of about 4 kg, and uses an open-loop controller to achieve steady crawling gait. The inchworm robot achieved a speed of 2.54 *** on level ground as well as on an incline plane of 19~. The energy usage as measured by the Mechanical Cost of Transport （a non-dimensional number defined as the energy used per unit weight per unit distance moved） is 3.34. Our results indicate that simple robotic designs that copy the basic features of natural organisms provide a promising alternative over conventional wheeled robots.

关键词： inchworm bioinspiration two-anchor crawl gait 3D printing sliding locomotion cost of transport

Navigating the controversy regarding antibiotic prophylaxis in acute variceal bleeding

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第18期30卷 2485-2487页

作者： David aguirre-Villarreal Ignacio García-Juárez Department of Gastroenterology and Liver Transplant Unit Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico

Antibiotic prophylaxis in patients with cirrhosis and acute variceal bleeding is part of the standard of care according to most clinical ***,with recent evidence arguing against antibiotic prophylaxis,the role of this... 详细信息

关键词： Cirrhosis Acute variceal bleeding Antibiotic prophylaxis Endoscopic band ligation Spontaneous bacterial peritonitis

The potential of starch-chitosan blends with poloxamer for the preparation of microparticles by spray-drying

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第6期89卷 1-10页

作者： Juan Enrique Barranco-García Carolina Caicedo Enrique Javier Jiménez-Regalado Carlos Espinoza-González Graciela Morales Rocio Yaneli aguirre-Loredo Abril Fonseca-García Tecnológico Nacional de México/Instituto Tecnológico de Oaxaca Departamento de Química y BioquímicaAvenida Ing.Víctor Bravo Ahuja No.125Esquina Calzada Tecnológico68030OaxacaMexico Faculty of Engineering Unidad Central del Valle del Cauca(UCEVA)Carrera 17a 48-144763022TuluáColombia Centro de Investigación en Química Aplicada(CIQA) Blvd.Enrique Reyna Hermosillo 14025294SaltilloCoahuilaMexico Investigadoras por México CONAHCYT-CIQA Av.Insurgentes Sur 1562Col.Crédito Constructor03940Alcaldía Benito JuárezCDMXMexico

Using biopolymers as wall materials in spray drying poses challenges,particularly in attaining flowability and thermal stability among their physicochemical *** paper addresses these challenges by preparing microparticles using a blend of starch–chitosan and a poloxamer,commercially named Pluronic®*** aimed to elucidate the effects of varying poloxamer concentrations on the resulting particles through the spray drying *** with a poloxamer concentration of 3%(w/v)demonstrated a notably higher yield,especially when compared to those with 0%and 1%*** with 3%and 5%(w/v)poloxamer displayed a narrower particle size distribution,with the 3%blend showing a superior yield attributed to arrangements of blend components that improve flowability.X-ray diffraction analysis showcased the characteristic peaks of A-type starch form,with shifts suggesting enhanced interactions between *** with increased poloxamer content showed elevated thermal degradation temperatures,with the 3%blend registering a significant rise,opening avenues for encapsulating heat-sensitive *** study primarily focuses on the preparation and basic characterization of *** underscores the potential of blends with optimal poloxamer concentrations in microencapsulation,emphasizing further research to harness their capabilities thoroughly.

关键词： Biopolymer Starch Chitosan Pluronic®F127 Microparticles Spray drying

Fabrication of sub-20 nm MoS_(2) horizontal nanowire on silicon substrates by inclusion of precursors into polystyrene-bpolyethylene oxide nanopatterns: Detailed structural investigation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 2145-2153页

作者： Tandra Ghoshal michael A.Morris School of Chemistry AMBER and CRANNTrinity College DublinDublinIrelandD02 AK60

Herein,we demonstrate the fabrication of sub-20 nm MoS_(2) horizontal nanowire arrays on silicon substrates using a self-assembled block copolymer assisted in situ inclusion *** separated long-range ordered polystyrene-b-polyethylene oxide(PS-b-PEO)block copolymer(BCP)line-space nanopatterns were achieved through thermo-solvent *** patterns produced had long-range order and domain sizes>1μ*** BCP structures were lightly etched and modified by anhydrous ethanol to facilitate insertion of molybdenum precursor within the film maintaining the parent BCP *** ordered molybdenum oxide nanowire arrays were then fabricated by ultraviolet(UV)/ozone treatment at room *** oxides were converted to sulphides by thermal evaporation at different temperatures in Ar/H_(2) environment.X-ray photoelectron spectroscopy revealed the composition and phases of the molybdenum oxide and sulphide *** mapping was performed to investigate the interfaces between the oxide and sulphide nanowires with the substrate *** formation and stability of the sulphide nanowires were studied at different *** photoluminescence and Raman properties were studied at different formation temperatures to investigate defects and estimate the number of layers.

关键词： MoS_(2) block copolymer nanowires inclusion X-ray photoelectron spectroscopy(XPS) mapping photoluminescence

A GHz chirped amplitude-modulated laser for high-contrast plasma gratings

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2024年第1期12卷 74-83页

作者： michael Valdman Amir Hen Gilad Marcus Applied Physics Institute Hebrew University of JerusalemJerusalemIsrael

The generation and control of large amplitude plasma gratings and other plasma structures is of paramount importance for the realization of plasma photonics. Autoresonant excitation of such structures by means of chirped amplitude-modulated lasers has been recently discussed and analyzed theoretically. Here we discuss the parameter space for the realization of such a scheme and describe the laser system that was built towards this goal. We also expand our earlier theoretical study to account for the more realistic case of a moderately focused laser beam, instead of the simplified plane wave approximation.

关键词： amplitude modulation high-frequency modulation autoresonance ion acoustic wave

Neuronal trafficking as a key to functional recovery in immune-mediated neuropathies

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第11期19卷 2331-2332页

作者： Felix Kohle michael Schroeter Department of Neurology University of Cologne and University Hospital CologneCologneGermany

Immune-mediated neuropathies are rare diseases of the peripheral nervous system(PNS),substantially affecting patients’functionality and quality of *** are amenable to immunomodulatory treatments,which in many cases stabilize disease progression,but long-term deficits persist in many *** long-term deficits are particularly observed in monophasic autoimmune neuropathies like Guillain-Barrésyndrome and also in chronic variants,e.g.,chronic inflammatory demyelinating neuropathy(Fadia et al.,2019).

关键词： diseases autoimmune

Transcranial photobiomodulation for the brain: a wide range of clinical applications

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第3期19卷 483-484页

作者： michael R.Hamblin Laser Research Centre Faculty of Health ScienceUniversity of Johannesburg-Doornfontein CampusDoornfonteinSouth Africa

Photobiomodulation therapy(PBMT)is a rapidly growing approach to the healing,stimulation,protection,and regeneration of many human organs and tissue *** started in the 1960s as low-level laser therapy for wound healing,but since then the introduction of light-emitting diodes(LEDs)has dramatically increased the number of applications and reports of positive *** generally uses red(620-700 nm)and/or near-infrared(780-1270 nm)wavelengths of light at an intensity that causes no tissue heating,and its activity is based on well-established biological and cellular mechanisms(de Freitas and Hamblin,2016).While laser therapists continue to use various types of laser in their office practice,LEDs are ideally suited for home use devices because they are completely safe and without any known significant adverse *** the various body parts on which PBMT has been shown to exert beneficial effects,the brain stands out as perhaps the most promising *** has been shown to reduce neuroinflammation,while increasing mitochondrial function,oxygen consumption,and blood flow within the brain(Hamblin,2016).Moreover,PBMT can stimulate the processes of synaptogenesis,neurogenesis,and neuroplasticity thus helping the brain to heal itself.

关键词： healing stimulation wound

A Tropical View on Landau-Ginzburg Models

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第1期40卷 329-382页

作者： michael CARL Max PUMPERLA Bernd SIEBERT Alfred-Delp-Str.2 73430 AalenGermany IU Internationale Hochschule Juri-Gagarin-Ring 15299084 ErfurtGermany AnyscaleInc.2080 Addison St Ste 7BerkeleyCA 94704USA Department of Mathematics The Univ.of Texas at Austin2515 SpeedwayAustinTX 78712USA

This paper,largely written in 2009/2010,fits Landau-Ginzburg models into the mirror symmetry program pursued by the last author jointly with Mark Gross since *** point of view transparently brings in tropical disks of Maslov index 2 via the notion of broken lines,previously introduced in two dimensions by Mark Gross in his study of mirror symmetry for P2.A ma jor insight is the equivalence of properness of the Landau-Ginzburg potential with smoothness of the anticanonical divisor on the mirror *** obtain proper superpotentials which agree on an open part with those classically known for toric *** include mirror LG models for non-singular and singular del Pezzo surfaces,Hirzebruch surfaces and some Fano threefolds.

关键词： Landau-Ginzburg model mirror symmetry tropical disk broken line wall structure scattering diagram Gross-Siebert program del Pezzo surface toric degeneration

Recent development and challenges in enhancing fire performance on wood and wood-based composites:A 10-year review from 2012 to 2021

在线全文

学校读者我要写书评

暂无评论

Journal of Bioresources and Bioproducts 2024年第1期9卷 27-42页

作者： Charles michael Albert Kang Chiang Liew Faculty of Tropical Forestry Universiti Malaysia SabahKota Kinabalu 88400Kota KinabaluSabah 88400Malaysia

Due to their durability,versatility,and aesthetic value,wood and wood-based composites are widely used as building *** fact that these materials are flammable,however,raises a major worry since they might cause fire hazards and significant loss of life and *** article investigates the variables that affect fire performance as well as the various fire-retardant treatments and their *** current developments and challenges in improving the fire performance of wood and wood-based composites treated with fire-retardant materials are summarized in this ***,organic chemicals,and densification are some recent developments in fire-retardant treatments that are also *** points from the review are summarized,along with potential areas for further research and development.

关键词： Fire performance Fire-retardant materials Wood Wood-based composite Nanoparticles coating Surface charring Bio-based fire retardant Densification

Implementation and validation of a bonded particle model to predict rheological properties of viscoelastic materials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第6期89卷 198-210页

作者： michael Mascara Arno Mayrhofer Stefan Radl Christoph Kloss Institute of Process and Particle Engineering Graz University of TechnologyInffeldgasse 13Graz8010Austria DCS Computing GmbH Industriezeile 35Linz4020Austria

This work focuses on implementing a particle-based method able to characterize viscoelastic materials whose rheological properties,such as storage modulus G′and loss modulus G″,are *** is based on the bonded particle model,with the elastic constitutive relation here substituted with a viscoelastic one to capture time-scale *** Burgers model,vastly used in literature to model viscoelastic systems,is discretized and *** test case used for calibration comprises of a cubic lattice,sheared with a periodic motion,to mimic the effect of a shear *** appropriate filtering of the stress response,the rheological properties are obtained,highlighting the effect of the lattice geometry,as well as the particle size,on the accuracy of the ***,the Burgers parameters are calibrated by analytically fitting the experimental dataset,showing the limitation of the Burgers *** micro-contact parameters are obtained from the macro parameters through appropriate *** completing a frequency sweep,the simulated G′and G″show a relatively large error,around 25%for G’for *** this reason,a more robust model,namely the generalized Maxwell model,has been *** calibration procedure is performed in the same fashion as for the Burgers ***,the tangential micro-contact parameters are scaled *** normal *** scaling parameter,calledα,is calibrated by minimizing the root mean square error between simulation and experimental data,giving errors below 10%in both G′and G″for a large ***,a full ring plate-plate rheometer setup is simulated,and the simulation is compared with the given experimental dataset,again finding a good agreement.

关键词： DEM Rheology Numerical modeling Viscoelasticity