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Chinese Journal of Chemical engineering 2019年第11期27卷 2788-2798页

作者： Sunel Kumar Zhihua Wang Zhang Kang Jun Xia ronald Whiddon Yong He Jaffri Gul-e-Rana Zain Ali Saleh Bairq Kefa Cen State Key Laboratory of Clean energy Utilization Zhejiang UniversityHangzhou 310027China Department of Mechanical Aerospace and Civil EngineeringBrunel University LondonUxbridge UB83PHUK Fuel Research Centre PCSIRKarachi 75280Pakistan College of Chemistry and Chemical engineering Hunan UniversityChangsha 410082China

The yield of tar and syngas has been investigated by catalytic pyrolysis of Pingzhuang lignite(PZL)over Ca(OH)2 catalyst in temperature range of 600℃-1000℃in a tube *** results show that the yield of volatile pyrolysis increases and char decreases with rising temperature for both raw and catalyzed Pingzhuang *** hydrogen fraction(H2)increased from 20%to 40%for the PZL sample;but,for the PZL-Ca(OH)2 sample,H2 fraction fluctuated randomly between 35%to 42%,with the maximum H2 fraction found at 1000℃.The Gaschromatography mass-spectroscopic(GC-MS)analysis revealed that the maximum tar yield at 800℃and 700℃was obtained for PZL and PZL-Ca(OH)2,*** surface morphology of PZL and PZL-Ca(OH)2 chars underwent different transformation in the presence of catalyst as illustrated by SeM/eDX,FTIR,and BeT ***,char sample was investigated for the carbon conversion and reactivity index using TGA analysis under N2 and CO atmosphere.

关键词： Catalyzed coal pyrolysis Release volatiles of tar and coal gas Surface area Pore volume

Processing, Recovery and Analysis of Precious Metals Using Molecular Recogntion Technology

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贵金属 2012年第A1期33卷 88-95页

作者： IZATT Steven R. BRUeNING ronald L. IZATT Nell e. IBC Advanced Technologies Inc.856 East Utah Valley DriveAmerican ForkUT 84003USA

IBC Advanced Technologies' Molecular Recognition Technology(MRT) products,trade named SuperLig,selectively and rapidly bind with target metal ions to remove them from *** MRT process can produce a high purity separation product of maximum added value at low *** this paper,applications of MRT in the precious metals industry,including selective commercial separations involving Au,Pd,Pt,Rh,and Ru,are described and *** of MRT to the analytical determination of precious metals is *** use of MRT in recovering precious metals from end-of-life(eOL) products is discussed.

关键词： selective metal separations molecular recognition technology metal recovery from waste electronics palladium platinum rhodium ruthenium gold analytical determinations

Balanced and Unbalanced Components of Moist Atmospheric Flows with Phase Changes

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Chinese Annals of Mathematics,Series B 2019年第6期40卷 1005-1038页

作者： Alfredo N.WeTZeL Leslie M.smith Samuel N.STeCHMANN Jonathan e.MARTIN Department of Mathematics University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics and Department of engineering Physics University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics and Department of Atmospheric and Oceanic Sciences University of Wisconsin-MadisonMadisonWI 53706USA Department of Atmospheric and Oceanic Sciences University of Wisconsin-MadisonMadisonWI 53706USA

Atmospheric variables(temperature, velocity, etc.) are often decomposed into balanced and unbalanced components that represent low-frequency and high-frequency waves, respectively. Such decompositions can be defined, for instance, in terms of eigenmodes of a linear operator. Traditionally these decompositions ignore phase changes of water since phase changes create a piecewise-linear operator that differs in different phases(cloudy versus non-cloudy). Here we investigate the following question: How can a balanced–unbalanced decomposition be performed in the presence of phase changes? A method is described here motivated by the case of small Froude and Rossby numbers,in which case the asymptotic limit yields precipitating quasi-geostrophic equations with phase changes. Facilitated by its zero-frequency eigenvalue, the balanced component can be found by potential vorticity(PV) inversion, by solving an elliptic partial differential equation(PDe), which includes Heaviside discontinuities due to phase changes. The method is also compared with two simpler methods: one which neglects phase changes, and one which simply treats the raw pressure data as a streamfunction. Tests are shown for both synthetic, idealized data and data from Weather Research and Forecasting(WRF) model simulations. In comparisons, the phase-change method and no-phase-change method produce substantial differences within cloudy regions, of approximately 5K in potential temperature, due to the presence of clouds and phase changes in the data. A theoretical justification is also derived in the form of a elliptic PDe for the differences in the two streamfunctions.

关键词： Potential vorticity inversion Moist atmospheric dynamics Slow-fast systems Balanced-unbalanced decomposition elliptic partial differential equations

A post-classical theory of enamel biomineralization… and why we need one

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International Journal of Oral Science 2012年第3期4卷 129-134页

作者： James P Simmer Amelia S Richardson Yuan-Yuan Hu Charles e.smith Jan Ching-Chun Hu Department of Biologic and Materials Sciences School of Dentistry University of Michigan Ann Arbor USA Facility for electron Microscopy Research Department of Anatomy and CellBiology and Faculty ofDentstry McGlIUniversity. Montreal Canada

enamel crystals are unique in shape, orientation and organization. They are hundreds of thousands times longer than they are wide, run parallel to each other, are oriented with respect to the ameloblast membrane at the mineralization front and are organized into rod or interrod enamel. The classical theory of amelogenesis postulates that extracellular matrix proteins shape crystallites by specifically inhibiting ion deposition on the crystal sides, orient them by binding multiple crystallites and establish higher levels of crystal organization. elements of the classical theory are supported in principle by in vitro studies; however, the classical theory does not explain how enamel forms in vivo. In this review, we describe how amelogenesis is highly integrated with ameloblast cell activities and how the shape, orientation and organization of enamel mineral ribbons are established by a mineralization front apparatus along the secretory surface of the ameloblast cell membrane.

关键词： ameloblastin amelogenin enamelin mineralization front tooth

Can science save the giant panda (Ailuropoda melanoleuca)? Unifying science and policy in an adaptive management paradigm

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Integrative Zoology 2011年第3期6卷 290-296页

作者： ronald R.SWAISGOOD Fuwen WeI William J.MCSHeA David e.WILDT Andrew J.KOUBA Zejun ZHANG San Diego Zoo Institute for Conservation Research EscondidoCaliforniaUSA Institute of Zoology Chinese Academy of ScienceBeijingChina Conservation&Research Center Smithsonian’s National Zoological ParkFront RoyalVirginiaUSA Memphis Zoo MemphisTennesseeUSA Institute of Rare Animals and Plants China West Normal UniversityNanchongSichuanChina

The giant panda(Ailuropoda melanoleuca David,1869)is an iconic species for global conservation,yet field research has only recently advanced to the point where adaptive management is ***,we review recent developments in giant panda conservation science and propose a strategic plan for moving panda conservation *** of scientific,funding,political,and logistical hurdles,few endangered species management programs have embraced adaptive management,wherein management decisions are shaped iteratively by targeted scientific *** threats,such as habitat destruction,anthropogenic disturbance and fragmented nonviable populations,need to be addressed simultaneously by researchers,managers and policy-makers working in concert to understand and overcome these obstacles to species *** the backing of the Chinese Govern-ment and the conservation community,the giant panda can become a high-profile test species for this much touted,but rarely implemented,approach to conservation management.

关键词： adaptive management conservation policy endangered species giant panda strategic conservation plan

An unusual presentation of primary sclerosing cholangitis

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World Journal of Gastroenterology 2008年第43期14卷 6748-6749页

作者： Franklin Whitney Goldwire William e Norris Jonathan M Koff Zachary D Goodman Milton T smith Internal Medicine Walter Reed Army Medical Center Washington DC 20307United States Gastroenterology Walter Reed Army Medical Center Washington DC 20307United States Armed Forces Institute of Pathology Washington DC 20307United States

This case report describes the unusual presentation of a patient who had findings which were initially suggestive of a type Ⅳ choledochal cyst. Her liver biopsy demonstrated biliary cirrhosis. She was treated with endoscopic retrograde cholangiopancreatography and biliary stent exchanges over one year. Her cholangiogram one year later demonstrated resolution of the biliary cystic dilation which led to her initial diagnosis, with beading and stricturing of the hepatic ducts consistent with primary sclerosing cholangitis. Liver-associated enzymes and physical findings also improved. A liver biopsy one year later demonstrated a marked improvement in hepatic fibrosis with no evidence of cirrhosis.

关键词： Biliary cysts Cholangiogram endoscopic retrograde cholangiopancreatography Liver fibrosis Primary sclerosing cholangitis

Can bacterial virulence factors predict antibiotic resistant Helicobacter pylori infection?

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World Journal of Gastroenterology 2018年第9期24卷 971-981页

作者： Denise e Brennan Colin Dowd Colm O'Morain Deirdre McNamara Sinéad M smith Department of Clinical Medicine School of Medicine Trinity College Dublin

AIM To evaluate the association between virulence factor status and antibiotic resistance in Helicobacter pylori(H. pylori)-infected patients in Ireland. MeTHODS DNA was extracted from antral and corpus biopsies obtained from 165 H. pylori-infected patients. Genotyping for clarithromycin and fluoroquinolone-mediating mutations was performed using the Genotype Helico DR assay. cag A and vac A genotypes were investigated using PCR. ReSULTS Primary, secondary and overall resistance rates for clarithromycin were 50.5%(n = 53/105), 78.3%(n = 47/60) and 60.6%(n = 100/165), respectively. Primary, secondary and overall resistance rates for fluoroquinolones were 15.2%(n = 16/105) and 28.3%(n = 17/60) and 20%(n = 33/165), respectively. Resistance to both antibiotics was 12.4%(n = 13/105) in treatment-na?ve patients, 25%(n = 15/60) in those previously treated and 17%(n = 28/165) overall. A cag A-positive genotype was detected in 22.4%(n = 37/165) of patient samples. The dominant vac A genotype was S1/M2 at 44.8%(n = 74/165), followed by S2/M2 at 26.7%(n = 44/165), S1/M1 at 23.6%(n = 39/165) and S2/M1 at 4.8%(n = 8/165). Primary clarithromycin resistance was significantly lower in cag A-positive strains than in cag A-negative strains [32%(n = 8/25) vs 56.3%(n = 45/80); P = 0.03]. Similarly, in patients infected with more virulent H. pylori strains bearing the vac A s1 genotype, primary clarithromycin resistance was significantly lower than in those infected with less virulent strains bearing the vac A s2 genotype, [41%(n = 32/78) vs 77.8%(n = 21/27); P = 0.0001]. No statistically significant association was found between primary fluoroquinolone resistance and virulence factor *** Genotypic H. pylori clarithromycin resistance is high and cag A-negative strains are dominant in our population. Less virulent(cag A-negative and vac A S2-containing) strains of H. pylori are associated with primary clarithromycin resistance.

关键词： Helicobacter pylori Antibiotic resistance Fluoroquinolone Clarithromycin Virulence factor VacA CagA

Investigation of a cyanine dye assay for the evaluation of the biocompatibility of magnesium alloys by direct and indirect methods

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Bioactive Materials 2020年第1期5卷 26-33页

作者： Afrah Al Hegy Ryan smith eric R.Gauthier Joy e.Gray-Munro Dept.of Chemistry and Biochemistry Laurentian UniversitySudburyOntarioP3E 2C6Canada

Magnesium and its alloys are promising candidates for a new generation of biodegradable metals in orthopaedic applications due to their excellent biocompatibility,biodegradability,and mechanical properties that are similar to natural ***,direct in vitro assessment of these materials in the presence of cells is complicated by degradation products from the alloy that lead to a false positive for the most commonly used cell adhesion and cell proliferation *** this paper,a cyanine dye was used to quantitatively evaluate the in vitro biocompatibility of a Mg AZ31 alloy by both direct and indirect *** cytotoxicity of the corrosion products was evaluated via an indirect method;a 25%decrease in cell viability compared to control samples was ***,direct assessment of cell adhesion and proliferation showed a statistically significant increase in cell number at the surface after 72 *** addition,the degradation rate and surface characteristics of the Mg AZ31 alloy were evaluated for both direct and indirect *** degradation rate was unaffected by the presence of cells while evidence of an increase in calcium phosphate deposition on the magnesium alloy surface in the presence of cells was *** study demonstrates that a cyanine dye based assay provides a more accurate assessment of the overall in vitro biocompatibility of biodegradable metals than the more commonly used assays reported in the literature to date.

关键词： Magnesium alloys Biocompatibility Direct method Indirect method Cyanine dye Cell adhesion Cell proliferation Cytotoxicity

美国山核桃外生菌根真菌多样性及土壤因子对其真菌群落结构的影响

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美国山核桃外生菌根真菌多样性及土壤因子对其真菌群落结构的影响

Water balloon-induced orbital fracture in an aviator

中国菌物学会第七届全国会员代表大会暨2017年学术年会

作者：葛再伟 Timothy Brenneman Gregory Bonito Matthew e.smith 中国科学院昆明植物研究所中国科学院东亚植物多样性与生物地理学重点实验室 Department of Plant Pathology University of Florida Department of Plant Pathology University of Georgia Department of Plant Soil and Microbial Sciences Michigan State University

美国山核桃是世界上重要的油料干果树种之一,具有较高的经济产出。利用焦磷酸测序技术,通过对美国山核桃主产区的佐治亚州和佛罗里达州25个样点的区域性取样,对美国山核桃的外生菌根多样性及土壤因子对其群落结构的影响进行了研究。发... 详细信息

美国山核桃是世界上重要的油料干果树种之一,具有较高的经济产出。利用焦磷酸测序技术,通过对美国山核桃主产区的佐治亚州和佛罗里达州25个样点的区域性取样,对美国山核桃的外生菌根多样性及土壤因子对其群落结构的影响进行了研究。发现至少14个外生菌根真菌支系中的96种外生菌根真菌可与美国山核桃形成共生关系,以Scleroderma sp.、Tomentella sp.、Inocybe radiata、Russula pectinatoides、Inocybe cf. calospora和Tuber lyonii为优势类群,其中近1/3的外生菌根真菌也与周边的胡桃科或壳斗科植物形成共生关系;美国山核桃的外生菌根真菌群落受土壤中的K、Ca、Mg、Mn、P、Zn等矿物质影响较大,但是受土壤有机质影响较小;p H浓度与/tuber-helvella、/galactinia、/pachyphloeus-amylascus以及/pisolithus-scleroderma等支系的物种多样性呈正相关关系,块菌发生的频度和相对丰度与土壤高p H呈显著的正相关关系。研究结果对美国山核桃幼苗培育及建立和管理块菌-美国山核桃种植体系具有重要参考价值。

关键词：美国山核桃块菌外生菌根真菌群落土壤pH 胡桃科

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Military Medical Research 2020年第2期7卷 245-248页

作者： Timothy e.Holland David M.smith Guy N.Gibson Jared G.Brinkerhoff Flight and Operational Medical Clinic 78th Medical Group655 Seventh StreetRobins Air Force BaseRobinsGA 31098USA Department of Radiology Ehrling Bergquist Clinic2501 Capehart RdOffutt AFBNEOffutt 68113-2160USA Flight and Operational Medical Clinic 5th Medical Group194 Missilie AveMinot AFBNDMinot 58705USA

Background:Orbital fractures are common injuries found in facial *** etiologies of orbital fractures include motor vehicle collisions and *** report the case of a 32-year-old male who suffered an orbital fracture from a water ***,we describe the aeromedical complications that may result from this ***,we attempt to answer the question of when a patient may return to flying after sustaining such an injury through review of the *** presentation:A 32-year-old male pilot with the United States Air Force was at an outdoor event with his unit when he was struck with a water balloon launched from a sling shot into his left *** afterwards,he had an onset of subcutaneous emphysema and was escorted to a nearby emergency *** tomography identified an orbital fracture with associated orbital and subcutaneous *** patient was evaluated by a plastic surgeon and was determined not to be a surgical *** weeks later,he returned to flying ***:Water balloons are thought to be safe and harmless ***,when coupled with sling shots,water balloons can become formidable projectiles capable of significant orbital injury including orbital *** injuries are concerning to aviators,as the most common sites for fractures of the orbit are the thin ethmoid and maxillary bones adjacent to the *** altitude,gases in the sinuses may expand and enter the orbit through these fractures,which may suddenly incapacitate the *** is important for flight surgeons to identify and assess these individuals to determine suitability for flying.

关键词： Boyle’s law Orbital emphysema Facial fracture