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Uncovering the dominant contribution of intermediate volatility compounds in secondary organic aerosol formation from biomass-burning emissions

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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 Lamkaddam Tianqu Cui Lu Qi mihnea Surdu Dongyu Wang Lin Du Imad El Haddad jay G.Slowik Andre S.H.Prevot Environment Research Institute Shandong University Laboratory of Atmospheric Chemistry Paul Scherrer Institute

Organic vapors from biomass burning are a major source of secondary organic aerosols(SOAs). Previous smog chamber studies found that the SOA contributors in biomass-burning emissions are mainly volatile organic compounds(VOCs). While intermediate volatility organic compounds(IVOCs) are efficient SOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to SOA formation has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA formation from wood burning, we find that IVOCs can contribute ～70% of the formed SOA, i.e.>2 times more than VOCs. This previously missing SOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that SOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

关键词： atmospheric chemistry biomass burning secondary organic aerosol intermediate volatility organic compounds

Formation of fine crystalline dolomites in lacustrine carbonates of the Eocene Sikou Depression, Bohai Bay Basin, East China

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Petroleum Science 2016年第4期13卷 642-656页

作者： Yong-Qiang Yang Long-Wei Qiu jay gregg Zheng Shi Kuan-Hong Yu School of Geosciences China University of Petroleum Department of Geology Oklahoma State University

The genesis of the fine crystalline dolomites that exhibit good to excellent reservoir properties in the upper fourth member of the Eocene Shahejie Formation（Es4s）around the Sikou Sag, Bohai Bay Basin, is uncertain. This paper investigates the formation mechanisms of this fine crystalline dolomite using XRD, SEm, thin section analysis and geochemical data. The stratigraphy of the Sikou lacustrine carbonate is dominated by the repetition of metre-scale, high-frequency deposition cycles, and the amount of dolomite within a cycle increases upward from the cycle bottom. These dolomite crystals are 2–30 μm in length, subhedral to anhedral in shape and typically replace both grains and matrix. They also occur as rim cement and have thin lamellae within ooid cortices. Textural relations indicate that the dolomite predates equant sparry calcite cement and coarse calcite cement. The Sr concentrations of dolomites range from 900 to 1200 ppm. Dolomite δ18O values（-11.3 to-8.2 ‰ PDB） are depleted relative to calcite mudstone（-8.3 to-5.4 ‰ PDB） that precipitated from lake water, while δ13C values（0.06–1.74 ‰ PDB） are within the normal range of calcite mudstone values（-2.13 to 1.99 ‰ PDB）. High87Sr/86Sr values（0.710210–0.710844） indicate that amounts of Ca2＋ and mg2＋have been derived from the chemical weathering of Palaeozoic carbonate bedrocks. The high strontium concentration indicates that hypersaline conditions were maintainedduring the formation of the dolomites and that the dolomites were formed by the replacement of precursor calcite or by direct precipitation.

关键词： Dolomite Lacustrine carbonate Eocene Sikou Sag Bohai Bay Basin

Storylines of family medicine Ⅸ:people and places—diverse populations and locations of care

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Family medicine and Community Health 2024年第S3期12卷 79-88页

作者： William B Ventres Leslie A Stone Emad R Abou-Arab Julio meza David S Buck Jerome W Crowder Jennifer Y C Edgoose Alexander Brown Ellen J Plumb Amber K Norris jay J Allen Lauren E Giammar John E Wood Scott m Dickson G Austin Brown Family and Preventive medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA Family medicine University of Michigan Medical SchoolAnn ArborMichiganUSA Family medicine University of California Los AngelesDavid Geffen School of MedicineLos AngelesCaliforniaUSA Community medicine University of HoustonTilman J Fertitta Family College of MedicineHoustonTexasUSA Social and Behavioral Sciences University of HoustonTilman J Fertitta Family College of MedicineHoustonTexasUSA Family medicine and Community Health University of Wisconsin-Madison School of Medicine and Public HealthMadisonWisconsinUSA NH Dartmouth Family medicine Residency ConcordNew HampshireUSA San Francisco VA medical Center San FranciscoCaliforniaUSA Duluth Family medicine Residency Program University of Minnesota Medical School Duluth CampusDuluthMinnesotaUSA UAmS Northeast Regional Campus Family medicine Residency Program JonesboroArkansasUSA Cascades East Family medicine Residency Program Oregon Health&Science University School of MedicineKlamath FallsOregonUSA

Storylines of Family medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅸ:people and places—diverse populations and locations of care’,authors address the following themes:‘LGBTQIA+health in family medicine’,‘A family medicine approach to substance use disorders’,‘Shameless medicine for people experiencing homelessness’,“Difficult”encounters—finding the person behind the patient’,‘Attending to patients with medically unexplained symptoms’,‘making house calls and home visits’,‘Family physicians in the procedure room’,‘Robust rural family medicine’and‘Full-spectrum family medicine’.may readers appreciate the breadth of family medicine in these essays.

关键词： illustration family dimensions

Effect of liner and porcelain application on zirconia surface structure and composition

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International Journal of Oral Science 2016年第3期8卷 164-171页

作者： Tariq F Alghazzawi gregg m Janowski Department of Prosthetic Dental Sciences College of DentistryTaibah University Department of materials Science and Engineering School of EngineeringThe University of Alabama at Birmingham

The purpose of this study was to determine if there is an effect of liner and porcelain application （layering and pressing techniques） on the surface of yttria-stabilized tetragonal zirconia polycrystals （Y-TZP）, which were exposed to permutations of liner, layered porcelain, and pressed porcelain. Scanning electron microscope （SEm）/energy dispersive spectroscope （EDS） was used to identify changes in composition and microstructure after removing liner and porcelain with hydrofluoric acid. Simulated aging was also conducted to determine the effect of liner and porcelain on low-temperature degradation. The control group had a typical equiaxed grain structure, referred to as unaffected. When covered with liner or porcelain, some areas changed in structure and composition and were termed affected. The frequency of affected sbructure decreased when liner was covered with either layered porcelain or pressed porcelain. There were statistical differences （P〈0.05） in the composition between affected and unaffected for zirconium （layered porcelain with liner： affected = 60% （0.8%）（m/m）, unaffected = 69% （4%）, layered porcelain without liner： affected = 59% （3%）, unaffected = 65% （3%）） and oxygen （layered porcelain with liner： affected = 35% （2%）, unaffected = 26% （4%）, layered porcelain without liner： affected = 35% （3%）, unaffected = 30% （2%））. However, there were statistical differences （P〈0.05） in the composition for zirconium and oxygen of the aged layered porcelain without liner only. The liner should not be used before porcelain application, especially when using the layering technique for zirconia restorations. Furthermore, pressing should be considered the technique of choice over layering.

关键词： aging coefficient of thermal expansion energy dispersive spectroscopy layering of porcelain pressing of porcelain scanning electron microscope zirconia

Evaluation of zirconia–porcelain interface using X-ray diffraction

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International Journal of Oral Science 2015年第3期7卷 187-195页

作者： Tariq F Alghazzawi gregg m Janowski Department of materials Science and Engineering School of Engineering The University of Alabama at Birmingham Department of Prosthetic Dental Sciences College of Dentistry Taibah University

The aim of this study was to determine if accelerated aging of porcelain veneering had an effect on the surface properties specific to a tetragonal-to-monoclinic transformation（TmT） of zirconia restorations. Thirty-six zirconia samples were milled and sintered to simulate core fabrication followed by exposure to various combinations of surface treatments including as-received（control）,hydrofluoric acid（HF）, application of liner plus firings, application of porcelain by manual layering and pressing with firing, plus accelerated aging. The quantity of transformed tetragonal to monoclinic phases was analyzed utilized an X-ray diffractometer and one-way analysis of variance was used to analyze data. The control samples as provided from the dental laboratory after milling and sintering process had no TmT（X m5 0）. There was an effect on zirconia samples of HF application with TmT（X m5 0.8%） and liner plus HF application with TmT（X m5 8.7%）. There was an effect of aging on zirconia samples（no veneering） with significant TmT（X m5 70.25%）. Both manual and pressing techniques of porcelain applications reduced the TmT（manual, X m5 4.41%, pressing,X m5 11.57%）, although there was no statistical difference between them. It can be concluded that simulated applications of porcelain demonstrated the ability to protect zirconia from TmT after aging with no effect of a liner between different porcelain *** HF treatment also caused TmT.

关键词： aging hydrofluoric acid monoclinic pressing tetragonal X-ray diffraction

Scientific observations at total solar eclipses

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

作者： jay m. Pasachoff Williams 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 number of space satellites from the U.S., Europe, Japan, and Russia study the Sun, scientists at eclipses can observe the solar chromosphere and corona at higher spatial resolution, at higher temporal resolution, and at higher spectral resolution than are possible aloft. Furthermore, eclipse expeditions can transport a wide variety of state-of-the-art equipment to the path of totality. Thus, for at least some years to come, solar eclipse observations will remain both scientifically valuable and cost-effective ways to study the outer solar atmosphere.

关键词： Sun eclipses

Effect of pH on Crystal Size and Photoluminescence Property of ZnO Nanoparticles Prepared by Chemical Precipitation method

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

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

The effects of pH value on crystal size and optical property of zinc oxide nanoparticles prepared by chemical precipitation method were *** samples have been characterized by means of X-ray diffraction,scanning electron microscopy,ultraviolet-visible spectrometer and photoluminescence *** X-ray diffraction profile,it is found that the particle size of sample 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 confirmed by the scanning electron microscopy *** recorded ultraviolet-visible spectrum shows excitonic absorption peaks around 381 *** energy gap of the prepared samples has been determined from the ultraviolet-visible absorption spectrum,effective mass model equation and Tauc＇s *** was found that the energy gap of the prepared samples decreases with increase in pH *** recorded blue shift confirmed the quantum confinement effect in the prepared zinc oxide *** spectrum infers that the increase in pH value shifts the ultraviolet-visible emission but not the violet and green emissions.

关键词： Zinc oxide nanoparticles pH value Crystal structure microstructure Energy gap Photoluminescence

Pain management strategies in penile implantation

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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 Simhan Department of Urology Einstein Healthcare NetworkDivision of Urologic OncologyDepartment of Surgical OncologyFox Chase Cancer CenterPhiladelphiaPA 19141 USA

The opioid epidemic continues to be a serious public health *** have pointed to prescription drug misuse as a nidus for patients to become addicted to opioids and as such,urologists and other surgical subspecialists must critically define optimal pain management for the various procedures performed within their respective *** pain following penile prosthesis implantation remains a unique challenge for urologists,given the increased pain patients commonly experience in the postoperative *** most of the existing urological literature focuses on interventions performed in the operating room,there are many studies that examine the role of preoperative adjunctive pain medicine in diminishing postoperative narcotic *** are relatively few studies looking at postoperative strategies for managing pain in prosthetic surgery with follow-up past the immediate *** review assess the various strategies employed for managing pain following penile implantation through the lens of the current state of the opioid crisis,thus examining how urologists can responsibly treat pain without contributing to the growing threat of opioid addiction.

关键词： analgesia epidemic opioid pain prosthetic

An update on the diagnosis of gastroenteropancreatic neuroendocrine neoplasms

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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 Department of Pathology&Clinical Labs University of MichiganAnn ArborMI 48109United States medical Scientist Training Program University of MichiganAnn ArborMI 48109United States

Gastroenteropancreatic neuroendocrine neoplasms(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,improved diagnostic modalities,and increased incidental detection on cross-sectional imaging and endoscopy for cancer screening and other conditions and ***-NENs are a heterogeneous group of tumors and have a wide range in clinical presentation,histopathologic features,and molecular *** presentation most commonly 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 tumors and neuroendocrine carcinomas,which can be identified using histology and molecular studies and are more aggressive with a worse prognosis compared to high-grade neuroendocrine *** our understanding of the biology of GEP-NENs has grown,new and improved diagnostic modalities can be developed and ***,we discuss clinical features and updates in diagnosis,including histopathological analysis,biomarkers,molecular techniques,and radiology of *** review established diagnostic tests and discuss promising novel diagnostic tests that are currently in development or require further investigation and validation prior to broad utilization in patient care.

关键词： Neuroendocrine tumor Neuroendocrine carcinoma Gastrointestinal Pancreas Pathology Diagnosis