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Transient Radiation-Conductive Heat transfer Problems:"The Quadrupole Method"

Journal of Thermal science 2002年第4期11卷 359-371页

作者： Alain Degiovanni benjamin Remy stephane Andre Laboratoire d'Energetique et de Mecanique Theorique et Appliquee L.E.M.T.A-U.M.R C.N.R.S 7563/E.E.I.G.M-E.N.S.E.MUniversite Henri Poincare-Nancy IInstitut National Polytechnique de Lorraine(I.N.P.L)02avenue de la Foret de Haye-B.P 16054516 Vandoeuvre-Les-Nancy CedexFrance

This paper presents a statement of the works performed in L.E.M.T.A by the members of the thermal and mechanical heterogeneous media research group during the last six years concerning the solving of coupled conductive and radiative heat transfers within a multilayer and semi-transparent“wall”.Out of the authors,this paper allows to take inspiration from the works of ***,*** and ***[19,20,21].The aim of these works is to represent in a macroscopic way,with the minimum number of thermophysical parameters,the heat transfers in a plane system composed of semi-transparent *** approach we propose is semi-analytic(Kernel substitution technique,Laplace transformation)and allow to obtain in the Laplace domain an analytical solution that can be easily *** method can be applied in two main scopes of applications:the estimation of thermophysical properties(phononic conductivity,optical thickness,Planck number for instance)of semi-transparent materials(glasses,crystals,glass wool,semi-conductors,synthetic diamonds,vitroceramics and so on)and the modelling of processes with semitransparent walls(for instance bottles forming,flat glass production,drying of paper).The method will be first presented and validated and two examples of applications will be then *** method can be applied to semitransparent walls that emit,absorb and scatter the radiant energy(participating medium).It appears from the principle of a Kernel substitution technique applied to the radiative flux expression and initially introduced by Lick[1]that allows to change the character of the governing heat equation from the integro-differential form to a purely differential *** the case of limiting cases of purely scattering and purely absorbing media,the solution of the radiative transfer equation is *** the general case,we make a two-flux *** all cases,we assume a linear transfer and use the Laplace *** method can be applied to grey or grey by bands

关键词： heat conduction thermal radiation coupled heat transfer quadrupole method

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Challenges in enriching milk fat with polyunsaturated fatty acids

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Journal of Animal science and Biotechnology 2016年第3期7卷 290-298页

作者： Jennifer stamey Lanier benjamin A.Corl Phibro Animal Health Corporation TeaneckN JUSA Department of Dairy science Virginia TechBlacksburgVA 24061-031 SUSA

Milk fatty acid composition is determined by several factors including diet. The milk fatty acid profile of dairy cows is low in polyunsaturated fatty acids, especially those of the n-3 series. Efforts to change and influence fatty acid profile with longer chain polyunsaturated fatty acids have proven challenging. several barriers prevent easy transfer of dietary polyunsaturated fatty acids to milk fat including rumen biohydrogenation and fatty acid esterification. The potential for cellular uptake and differences in fatty acid incorporation into milk fat might also have an effect, though this has received less research effort. Given physiological impediments to enriching milk fat with polyunsaturated fatty acids, manipulating the genome of the cow might provide a greater increase than diet alone, but this too may be challenged by the physiology of the cow.

关键词： Dairy cow Milk fat Polyunsaturated fatty acids

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Evolution of Morphology and structure During Crystallization and Melting in syndiotactic Polypropylene

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应用化学 2001年第5期18卷 280-288页

作者： Zhi-Gang WANG benjamin s.HsIAO Charles C.HAN state University of New York at stony Brook Department of ChemistryStony BrookNY 11794-3400 Polymers Division and Center for Neutron Research National Institute of Standards and TechnologyGaithersburgMD 20899

structure and morphology development during isothermal crystallization and subsequent melting of syndiotactic polypropylene(sPP) was studied by time-resolved simultaneous small-angle X-ray scattering(sAXs) and wide-angle X-ray diffraction(WAXD) methods with synchrotron radiation and differential scanning calorimetry(DsC). The time and temperature dependent parameters such as long period, L , crystal lamellar thickness, l c, amorphous layer thickness, l a, scattering invariant, Q , crystallinity, X c, lateral crystal sizes, L 200 and L 020 , and unit cell parameters a and b were extracted from sAXs and WAXD profiles. Decreasing long period and crystal thickness indicate that thinner secondary crystal lamellae are formed. The decreases in unit cell parameters a and b during isothermal crystallization process suggest that crystal perfection takes place. The changes in the morphological parameters (the invariant, Q , crystallinity, X c, long period, L , and the crystal thickness, l c) during subsequent melting were found to follow a two-stage melting process, corresponding to the dual endotherm behavior in the DsC scan. We conclude that the dual melting peaks are due to the melting of secondary and primary lamellae(first peak) and the subsequent recrystallization-melting process(second peak). Additional minor endothermic peak located at the lowest temperature was also detected and might be related to melting of secondary, thinner and defective lamellae. WAXD showed that during melting, thermal expansion was greater along the b axis than that along the a axis.

关键词：间规聚丙烯结晶熔化晶体结构 DCs sAXs WAXD

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Observing the stages of bystander intervention in virtual reality simulation

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World Journal of Emergency Medicine 2019年第3期10卷 145-151页

作者： David G. Buckler Alfredo Almodovar Jr Paul snobelen benjamin s. Abella Audrey Blewer Marion Leary Center for Resuscitation science University of Pennsylvania Philadelphia PA 19104 USA Peel Regional Paramedic service 1600 Bovaird Dr. E Brampton ON L6R 3S8 Canada Department of Community & Family Medicine Duke University Medical Center DUMC 2914 Durham NC 27710 USA school of Nursing University of Pennsylvania 418 Guardian Drive Philadelphia PA 19104 USA

BACKGROUND: Understanding bystander reactions to an emergency is an important component of effective training. Four stages of bystander intervention (BI) have been previously described: noticing the situation as a problem, interpreting when it is appropriate to intervene, recognizing personal responsibility to intervene, and knowing how to intervene. Using virtual reality (VR) to simulate emergencies such as sudden cardiac arrest (sCA) can be used to study these stages. METHODs: In a secondary analysis of an observational cohort study, we analyzed bystander self-effi cacy for stages of BI before and after simulated sCA. Each subject participated in a singleplayer, immersive, VR sCA scenario. subjects interacted with simulated bystanders through voice commands (“call 911”,“get an AED”). Actions taken in scenario, like performing CPR, were documented. scenario BI actions were compared based on dichotomized comfort/discomfort. REsULTs: From June 2016 to June 2017, 119 subjects participated. Average age was 37±14 years, 44% were female and 46% reported CPR training within 2 years. During the scenario, 98%“noticed the event” and “interpreted it as a problem”, 78%“took responsibility”, and 54%“possessed the necessary skills”. self-effi cacy increased from pre- to post-scenario: noticing the event increased from 80% to 96%;interpreting as a problem increased from 86% to 97%;taking responsibility increased from 56% to 93%;possessing necessary skills increased from 47% to 63%(PsION: self-efficacy to respond to an sCA event increased pre- to post-scenario. Bystanders who reported feeling comfortable “taking responsibility to intervene” during an emergency were more likely to take action during a simulated emergency.

关键词： Virtual reality Bystander intervention Emergency preparedness

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Preventative medicine and Alzheimer's disease: is Alzheimer's disease risk reduction achievable?

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Neural Regeneration Research 2021年第9期16卷 1772-1773页

作者： benjamin sinyor Richard Isaacson Christopher Ochner HCA Healthcare NashvilleTNUSA Weil Cornell Medicine New York Presbyterian HospitalNew YorkNYUSA

Alzheimer 's disease(AD) has a multifactorial etiology that has eluded scientists and clinicians for decades. This incomplete understanding of the causal factors likely contributes to the dearth of effective therapeut... 详细信息

关键词： Alzheimer elude likely

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Biological synthesis of silver Nanoparticles from Allium Cepa(Onion) & Estimating Its Antibacterial Activity

Biological Synthesis of Silver Nanoparticles from Allium Cep...

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International Conference on Bioscience, Biochemistry and Bioinformatics（ICBBB 2011）

作者： benjamin.G Bharathwaj.s student Department of Biotechnology St.Joseph's college of engineering ChennaiIndia

ISBN: (纸本)9789810887186

we used onion(Allium cepa) extract as a reducing and capping agent to minimize the serious environmental pollution *** onion extract was mixed with silver nitrate solution by heating to a temperature of 50-60 degree Celsius and the reduction reaction was studied by observing the color *** were synthesized by this method having 33.6 nm average mean *** preparation of nanoparticles by using onion extract has desired quality with low cost and convenient *** nanoparticles at concentration 50mg/ml were showed complete antibacterial activity against *** antibacterial activity was studied for 25 hours with varying concentrations of silver *** size of the nanoparticles was confirmed by subjecting the nanoparticle to TEM analysis and the antibacterial activity by UV-VIsIBLE sPECTROMETER.

关键词： onion,silver nanoparticles,reduction reaction,antibacterial activity,uv-vis spectroscopy,low cost

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structural characterization of carboxyl cellulose nanofibers extracted from underutilized sources

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science China(Technological sciences) 2019年第6期62卷 971-981页

作者： ZHAN ChengBo sHARMA Priyanka R. GENG LiHong sHARMA sunil K. WANG RuiFu JOsHI Ritika HsIAO benjamin s. Department of Chemistry Stony Brook University Stony Brook NY 11794-3400 USA National Engineer Research Center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing Engineering of Ministry of Education South China University of Technology Guangzhou 510640 China

Two different chemical methods, TEMPO-oxidation and nitro-oxidation, were used to extract carboxyl cellulose nanofibers(CNFs) from non-wood biomass sources(i.e., jute, soft and hard spinifex grasses). The combined TEMPO-oxidation and homogenization approach was very efficient to produce CNFs from the cellulose component of biomass;however, the nitrooxidation method was also found to be effective to extract CNFs directly from raw biomass even without mechanical *** effect of these two methods on the resulting cross-section dimensions of CNFs was investigated by solution small-angle Xray scattering(sAXs), transmission electron microscopy(TEM) and atomic force microscopy(AFM). The UV-Vis spectroscopic data from 0.1 wt% TEMPO-oxidized nanofiber(TOCNF) and nitro-oxidized nanofiber(NOCNF) suspensions showed that TOCNF had the highest transparency(> 95%) because of better dispersion, resulted from the highest carboxylate content(1.2 mmol/g). The consistent scattering and microscopic results indicated that TOCNFs from jute and spinifex grasses possessed rectangular cross-sections, while NOCNFs exhibited near square cross-sections. This study revealed that different oxidation methods can result in different degrees of biomass exfoliation and different CNF morphology.

关键词： cellulose nanofibers TEMPO-oxidation nitro-oxidation sAXs microscopy jute spinifex

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Efficient visual learning by bumble bees in virtual-reality conditions:size does not matter

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Insect science 2023年第6期30卷 1734-1748页

作者： Gregory Lafon Marco Paoli benjamin HPaffhausen Gabriela de Brito sanchez Mathieu Lihoreau Aurore Avarguès-Weber Martin Giurfa Centre de Recherches sur la Cognition Animale Centre de Biologie Intégrative(CBI)University of ToulouseCNRSUPSToulouseFrance French Academy of sciences for University Professors Institut Universitaire de France(IUF)ParisFrance

Recent developments allowed establishing virtual-reality (VR) setups to study multiple aspects of visual learning in honey bees under controlled experimental conditions. Here, we adopted a VR environment to investigate the visual learning in the buff-tailed bumble bee Bombus terrestris. Based on responses to appetitive and aversive reinforcements used for conditioning, we show that bumble bees had the proper appetitive motivation to engage in the VR experiments and that they learned efficiently elemental color discriminations. In doing so, they reduced the latency to make a choice, increased the proportion of direct paths toward the virtual stimuli and walked faster toward them. Performance in a short-term retention test showed that bumble bees chose and fixated longer on the correct stimulus in the absence of reinforcement. Body size and weight, although variable across individuals, did not affect cognitive performances and had a mild impact on motor performances. Overall, we show that bumble bees are suitable experimental subjects for experiments on visual learning under VR conditions, which opens important perspectives for invasive studies on the neural and molecular bases of such learning given the robustness of these insects and the accessibility of their brain.

关键词： Bombus terrestris bumble bees interindividual size/weight differences reinforcement responses visual learning virtual reality

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special Topic： Cretaceous greenhouse palaeoclimate and sea-level changes

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science China Earth sciences 2017年第1期60卷 1-4页

作者： XiuMian HU Michael WAGREICH benjamin sAMEs state Key Laboratory of Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University China Department of Geodynamics and sedimentology Center for Earth Sciences University of Vienna Austria

Earth＇s climate has oscillated between greenhouse （warm） and icehouse （cold） modes throughout Earth history. At present, Earth is in the midst of an icehouse climate interval, despite the anthropogenic contribution to global warming and sea-level rise due to industrialization during the past two centuries. This led to a dramatic increase in atmospheric CO2, mainly caused by the extensive burning of fossils fuels. The Cretaceous （145 to 66 million years ago） is the youngest prolonged greenhouse climate interval in the Phanerozoic, marked by very high global mean temperatures with some extreme warming peaks （＇hothouse＇ or ＇supergreenhouse＇）, largely absence of permanent continental ice sheets, a mean global sea-level having been some 250 m higher than that of today, and levels of carbon dioxide 4 to 10 times higher than those of the pre-industrial era. If temperature will continue to rise as quickly as in the last three decades, we are close to being at the cusp to a new greenhouse climate interval facing quickly rising global sea-level and reaching atmospheric CO2 levels of the ＇Cretaceous supergreenhouse＇ in about the years 2190-2260 （Hay, 2011）. Evidence from Earth＇s history indicates that glacial-interglacial climate mode changes as well as past sea-level changes such as in the Cretaceous greenhouse occurred at rates orders of magnitude slower than observed at present. The recent rise in global sea-level in response to rising levels of atmospheric greenhouse gases, the associated global warm- ing, and the waning of continental ice shields is a primary concern for human society. To predict future sea-levels we need a better understanding of the record of past sea-level changes, especially in the greenhouse palaeoclimate modes. Therefore, understanding the Cretaceous palaeoclimate is essential for a more accurate prediction of future global climate, sea-level rise and environmental changes in a prospective ＇Cretaceous-like＇ greenhouse Earth.

关键词： greenhouse Cretaceous warming anthropogenic despite throughout

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A new rat model of portal hypertension induced by intraportal injection of microspheres

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World Journal of Gastroenterology 1998年第1期4卷 71-74页

作者： LI Xiang-Nong Is benjamin B Alexander Department of Liver surgery Affiliated Hospital Xuzhou Medical College Xuzhou 221002 China Department of Liver surgery Affiliated Hospital Xuzhou Medical College China Xuzhou Medical College China Beijing Medical University China Department of surgery King's College School and Dentistry United Kingdom Department of Liver surgery Affiliated Hospital Xuzhou Medical College 50 Jiaheqian Street Xuzhou 221002 China Department of surgery King's Coll. Sch. of Med. and Dent. London United Kingdom

IM To produce a new rat model of portal hypertension by intraportal injection of microspheres.METHODs Measured aliquots of single or differentsized microspheres (15, 40, 80μm) were injected into the portal vein to block intrahepatic portal radicals. The resultant changes in arterial, portal, hepatic venous and splenic pulp pressures were monitored. The liver and lungs were excised for histological examination.REsULTs Portal venous pressure was elevated from basal value of 089-102 kPa to a steadystate of 198-319 kPa following the sequential injections of single or differentsized microspheres, with a markedly lowered mean arterial pressure. However, a smalldose injection of 80μm microspheres (18×105) produced a steadystate portal venous pressure of 253±017 kPa, and all rats showed normal arterial pressures. In addition, numerous microspheres were found in the lungs in all experimental groups.CONCLUsION Portal hypertension can be reproduced in rats by intraportal injection of microspheres at a small dose of 80μm (18×105). Intrahepatic portalsystemic shunts probably exist in the normal rat liver..

关键词： portal vein hypertension,portal disease model,animal latex microsphere

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