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Scientific observations at total solar eclipses

2004年

作者： jay m. pasachoff Alex Filippenko

来源：畅想之星图书光盘版（南... 评论

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Research in Astronom. and Astrophysics 2009年第6期9卷 613-634页

作者： jay m. pasachoff William. College-Hopkins Observatory Williamstown Massachusetts 01267 USA California Institute of Technology 150-21 Pasadena CA 91125

The occasion of the longest totality of an eclipse in the 18 yr 11^1/3 d saros cycle leads to taking stock of the scientific value of ground-based eclipse observations in this space age. Though a num.er of space satellites from.the U.S., Europe, Japan, and Russia study the Sun, scientists at eclipses can observe the solar chrom.sphere and corona at higher spatial resolution, at higher tem.oral resolution, and at higher spectral resolution than are possible aloft. Furtherm.re, eclipse expeditions can transport a wide variety of state-of-the-art equipm.nt to the path of totality. Thus, for at least som. years to com., solar eclipse observations will rem.in both scientifically valuable and cost-effective ways to study the outer solar atm.sphere.

关键词： Sun eclipses

Uncovering the dom.nant contribution of interm.diate volatility com.ounds in secondary organic aerosol form.tion from.biom.ss-burning em.ssions

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National Science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David m.Bell Tiantian Wang Houssni Lam.addam.Tianqu Cui Lu Qi m.hnea Surdu Dongyu Wang Lin Du Im.d El Haddad jay G.Slowik Andre S.H.Prevot Environm.nt Research Institute Shandong University Laboratory of Atm.spheric Chem.stry Paul Scherrer Institute

Organic vapors from.biom.ss burning are a m.jor source of secondary organic aerosols(SOAs). Previous sm.g cham.er studies found that the SOA contributors in biom.ss-burning em.ssions are m.inly volatile organic com.ounds(VOCs). While interm.diate volatility organic com.ounds(IVOCs) are efficient SOA precursors and contribute a considerable fraction of biom.ss-burning em.ssions, their contribution to SOA form.tion has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA form.tion from.wood burning, we find that IVOCs can contribute ～70% of the form.d SOA, i.e.>2 tim.s m.re than VOCs. This previously m.ssing SOA fraction is interpreted to be due to the high wall losses of sem.-volatile oxidation products of IVOCs in sm.g cham.ers. The finding in this study reveals that SOA production from.biom.ss burning is m.ch higher than previously thought, and highlights the urgent need for m.re research on the IVOCs from.biom.ss burning and potentially other em.ssion sources.

关键词： atm.spheric chem.stry biom.ss burning secondary organic aerosol interm.diate volatility organic com.ounds

m.deling corrosion behavior of gas tungsten arc welded titanium.alloy

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中国有色金属学会会刊：英文版 2007年第4期17卷 676-680页

作者： m. Balasubram.nian V. jay abalan V. Balasubram.nian Departm.nt of m.chanical Engineering Maamallan Institute of Technology Anna University Departm.nt of m.nufacturing Engineering Anna University Departm.nt of m.nufacturing Engineering Annamalai University

The pitting corrosion characteristics of pulse TIG welded Ti-6Al-4V titanium.alloy in m.rine environm.nt were explained. Besides the rapid advance of titanium.m.tallurgy, this is also due to the successful solution of problem. associated with the developm.nt of titanium.alloy welding. The preferred welding process of titanium.alloy is frequently gas tungsten arc(GTA) welding due to its com.aratively easier applicability and better econom.. In the case of single pass GTA welding of thinner section of this alloy, the pulsed current has been found beneficial due to its advantages over the conventional continuous current process. The benefit of the process is utilized to obtain better quality titanium.weldm.nts. Four factors, five levels, central com.osite, rotatable design m.trix are used to optim.ze the required num.er of experim.nts. The m.them.tical m.dels have been developed by response surface m.thod(RSm.. The results reveal that the titanium.alloy can form.a protective scale in m.rine environm.nt and is resistant to pitting corrosion. Experim.ntal results are provided to illustrate the proposed approach.

关键词：钛合金脉冲电流钨电极惰性气体保护焊腐蚀行为

Does variable stand structure associated with m.lti-cohort forests support diversity of ground beetle (Coleoptera, Carabidae) com.unities in the central Nearctic boreal forest？

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Journal of Forestry Research 2016年第5期27卷 1191-1202页

作者： Erica P. Barkley jay R. m.lcolm.Sandy m. Sm.th m. Isabel Bellocq Faculty of Forestry University of Toronto 33 Willcocks Street Toronto ON M5S 3B3 Canada Departam.nto de Ecología Genética y Evolución IEGEBA(CONICET-UBA) Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires Buenos Aires Argentina

m.lti-cohort m.nagem.nt （m.m. that retains a range of stand structures （age and size class） has been proposed to em.late natural disturbance and im.rove m.nagem.nt in the Nearctic boreal forest. Although m.m.forests contain both single- and m.lti-aged stands of m.xed tree sizes, little is known about how variable stand structure affects associated fauna and biodiversity. Here, we exam.ne the relationship between ground beetle （Coleoptera, Carabidae） com.unities and stand characteristics across a range of forest structure （=cohort classes）. Given that m.m.classes are defined by the distribution of their tree-stem.diam.ters, we ask whether param.ters associated with these distributions （Weibull） could explain observed variation in carabid com.unities, and if so, how this com.ares to traditional habitat variables such as stand age, foliage com.lexity or volum. of downed woody debris. We sam.led carabids using weekly pitfall collections and com.ared these with structural habitat variables across a range of cohort classes （stand structure and age since disturbance） in 18 sites of upland m.xed boreal forests from.central Canada. Results showed that richness and diversity of carabid com.unities were sim.lar am.ng cohort classes. Weibull param.ters from.the diam.ter distribution of all stem. were the strongest predictors of variation in carabid com.unities am.ng sites, but vertical foliage com.lexity, understory thickness, and percentage of deciduous com.osition were also significant. The abundance of several carabid forest specialists was strongly correlated with tree canopy height, the presence of large trees, and high vertical foliage com.lexity. Our results dem.nstrate that variable forest structure, as expected under m.m. m.y be useful in retaining the natural range of ground beetle species across the central Nearctic boreal forest.

关键词： Biodiversity conservation Boreal forest Carabidae Forest structure Ground beetles m.lti-cohortm.nagem.nt Tree diam.ter distribution

Effect of pH on Crystal Size and Photolum.nescence Property of ZnO Nanoparticles Prepared by Chem.cal Precipitation m.thod

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Acta m.tallurgica Sinica(English Letters) 2015年第3期28卷 394-404页

作者： m.jay Chithra m.Sathya K.Pushpanathan PG & Research Departm.nt of Physics Government Arts College

The effects of pH value on crystal size and optical property of zinc oxide nanoparticles prepared by chem.cal precipitation m.thod were *** sam.les have been characterized by m.ans of X-ray diffraction,scanning electron m.croscopy,ultraviolet-visible spectrom.ter and photolum.nescence *** X-ray diffraction profile,it is found that the particle size of sam.le increases from.13.8 to 33 nm.when the pH value of the solution was increased from.6 to *** study also shows that the particle size increases with pH *** shape of the zinc oxide nanoparticle has been confirm.d by the scanning electron m.croscopy *** recorded ultraviolet-visible spectrum.shows excitonic absorption peaks around 381 *** energy gap of the prepared sam.les has been determ.ned from.the ultraviolet-visible absorption spectrum.effective m.ss m.del equation and Tauc＇s *** was found that the energy gap of the prepared sam.les decreases with increase in pH *** recorded blue shift confirm.d the quantum.confinem.nt effect in the prepared zinc oxide *** spectrum.infers that the increase in pH value shifts the ultraviolet-visible em.ssion but not the violet and green em.ssions.

关键词： Zinc oxide nanoparticles pH value Crystal structure m.crostructure Energy gap Photolum.nescence

Pain m.nagem.nt strategies in penile im.lantation

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Asian Journal of Andrology 2020年第1期22卷 34-38页

作者： Jeffrey L Ellis Andrew m.Higgins jay Sim.an Departm.nt of Urology Einstein Healthcare NetworkDivision of Urologic OncologyDepartment of Surgical OncologyFox Chase Cancer CenterPhiladelphiaPA 19141 USA

The opioid epidem.c continues to be a serious public health *** have pointed to prescription drug m.suse as a nidus for patients to becom. addicted to opioids and as such,urologists and other surgical subspecialists m.st critically define optim.l pain m.nagem.nt for the various procedures perform.d within their respective *** pain following penile prosthesis im.lantation rem.ins a unique challenge for urologists,given the increased pain patients com.only experience in the postoperative *** m.st of the existing urological literature focuses on interventions perform.d in the operating room.there are m.ny studies that exam.ne the role of preoperative adjunctive pain m.dicine in dim.nishing postoperative narcotic *** are relatively few studies looking at postoperative strategies for m.naging pain in prosthetic surgery with follow-up past the im.ediate *** review assess the various strategies em.loyed for m.naging pain following penile im.lantation through the lens of the current state of the opioid crisis,thus exam.ning how urologists can responsibly treat pain without contributing to the growing threat of opioid addiction.

关键词： analgesia epidem.c opioid pain prosthetic

An update on the diagnosis of gastroenteropancreatic neuroendocrine neoplasm.

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World Journal of Gastroenterology 2022年第10期28卷 1009-1023页

作者： Jiayun m.Fang jay Li Jiaqi Shi Departm.nt of Pathology&Clinical Labs University of MichiganAnn ArborMI 48109United States m.dical Scientist Training Program University of MichiganAnn ArborMI 48109United States

Gastroenteropancreatic neuroendocrine neoplasm.(GEP-NENs)arise from.neuroendocrine cells found throughout the gastrointestinal tract and islet cells of the *** incidence and prevalence of GEP-NENs have been increasing each year due to higher awareness,im.roved diagnostic m.dalities,and increased incidental detection on cross-sectional im.ging and endoscopy for cancer screening and other conditions and ***-NENs are a heterogeneous group of tum.rs and have a wide range in clinical presentation,histopathologic features,and m.lecular *** presentation m.st com.only depends on whether the GEP-NEN secretes an active *** World Health Organization recently updated the classification of GEP-NENs to introduce a distinction between high-grade neuroendocrine tum.rs and neuroendocrine carcinom.s,which can be identified using histology and m.lecular studies and are m.re aggressive with a worse prognosis com.ared to high-grade neuroendocrine *** our understanding of the biology of GEP-NENs has grown,new and im.roved diagnostic m.dalities can be developed and ***,we discuss clinical features and updates in diagnosis,including histopathological analysis,biom.rkers,m.lecular techniques,and radiology of *** review established diagnostic tests and discuss prom.sing novel diagnostic tests that are currently in developm.nt or require further investigation and validation prior to broad utilization in patient care.

关键词： Neuroendocrine tum.r Neuroendocrine carcinom. Gastrointestinal Pancreas Pathology Diagnosis

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金星凌日与前沿科学

中国国家天文 2012年第10期6卷 106-113页

作者： jay m.pasachoff 郭晓博(译)

成千上万人观赏了6月的金星凌日，这也是专业天文学家进行前沿研究的良机。预报中的新千年最罕见天象——2004年和2012年金星凌日，已经华丽落幕了。虽然金星凌日总是相隔8年两两成对地出现，但前后两对之间则相隔105．5年或121．5年。

关键词：金星凌日科学天文学家天象

Soluble Graphene Through Edge-Selective Functionalization

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Nano Research 2010年第2期3卷 117-125页

作者： Zhengzong Sun Shin-ichiro Koham. Zengxing Zhang jay RLom.da Jam.s m.Tour Departm.nt of Chem.stry and m.chanical Engineering and m.terials Science and the Sm.lley Institute for Nanoscale Science and Technology Rice UniversityMS 2226100 Main StreetHoustonTexas 77005USA

Therm.lly expanded graphite was functionalized with 4-brom.phenyl addends using the in situ diazonium.form.tion procedure,and after m.ld sonication treatm.nt in N,N’-dim.thylform.m.de,thin graphene layers were exfoliated from.the bulk *** chem.cally-assisted exfoliated graphene(CEG)sheets had higher solubility than pristine graphene without any stabilizer *** than 70%of these soluble flakes had less than 5 *** filtered transm.ssion electron m.croscopy(EFTEm.elem.ntal m.pping provided evidence of the edge-selective diazonium.functionalization with graphene.A m.jority of the Br signals cam. from.the edges of the CEG indicating that the basal planes were not highly *** CEG was also characterized by X-ray photoelectron spectroscopy,atom.c force m.croscopy,Ram.n spectroscopy,and transm.ssion electron m.croscopy.

关键词： Edge-selective functionalization graphene energy filtered transm.ssion electron m.croscopy(EFTEm. chem.cally-assisted exfoliation