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Frontiers of Chemical Science and Engineering 2018年第1期12卷 162-173页

作者： Muhammad I. Asghar Sakari Lepikko Janne Patakangas Janne Halme peter d. Lund New Energy Technologies Group Department of Applied Physics Aalto University P.O. BOX 15100 FI-00076 Aalto Finland

A comparative analysis of perovskite structured cathode materials, La0.65Sr0.35Mn03 （LSM）, La0.8Sr0.2CoO3 （LSC）, La0.6Sr0.4FeO3 （LSF） and La0.6Sr0.4Co0.2Fe0.803 （LSCF）, was performed for a ceramic-carbonate nanocomposite fuel cell using composite electrolyte consisting of Gd0.1Ce0.9O1.95 （GdC） and a eutectic mixture of Na2CO3 and Li2CO3. The compatibility of these nanocomposite electrode powder materials was investigated under air, CO2 and air/CO2 atmospheres at 550 ℃. Microscopy measurements together with energy dispersive X-ray spectroscopy （EdS） elementary analysis revealed few spots with higher counts of manganese relative to lanthanum and strontium under pure CO2 atmosphere. Furthermore, electrochemical impedance （EIS） analysis showed that LSC had the lowest resistance to oxygen reduction reaction （ORR）（14.12 Ω·cm^2） followed by LSF （15.23 Ω·cm^2）, LSCF （19.38Ω·cm^2） and LSM （〉 300 Ω·cm^2）. In addition, low frequency EIS measurements （down to 50 gHz） revealed two additional semi-circles at frequencies around 1 Hz. These semicircles can yield additional information about electrochemical reactions in the device. Finally, a fuel cell was fabricated using GdC/NLC nanocomposite electrolyte and its composite with NiO and LSCF as anode and cathode, respectively. The cell produced an excellent power density of 1.06 W/cm^2 at 550 ℃ under fuel cell conditions.

关键词： electrode fuel cell low-temperature nano- composite perovskite

ON THE MOdIFIEd NONLINEAR SCHRdINGER EQUATION IN THE SEMICLASSICAL LIMIT:SUPERSONIC,SUBSONIC,ANd TRANSSONIC BEHAVIOR

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Acta Mathematica Scientia 2011年第6期31卷 2343-2377页

作者： Jeffery C. diFranco peter d. Miller Benson K. Muite department of Mathematics Seattle University department of Mathematics University of Michigan

The purpose of this paper is to present a comparison between the modified nonlinear SchrSdinger （MNLS） equation and the focusing and defocusing variants of the （unmodified） nonlinear SchrSdinger （NLS） equation in the semiclassical limit. We describe aspects of the limiting dynamics and discuss how the nature of the dynamics is evident theoretically through inverse-scattering and noncommutative steepest descent methods. The main message is that, depending on initial data, the MNLS equation can behave either like the defocusing NLS equation, like the focusing NLS equation （in both cases the analogy is asymptotically accurate in the semiclassical limit when the NLS equation is posed with appropriately modified initial data）, or like an interesting mixture of the two. In the latter case, we identify a feature of the dynamics analogous to a sonic line in gas dynamics, a free boundary separating subsonic flow from supersonic flow.

关键词： semiclassical limits dispersionless limits modulational instability focusing,defocusing, and modified nonlinear SchrSdinger equations

Molecular targets in the treatment of alcoholic hepatitis

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World Journal of Gastroenterology 2012年第39期18卷 5504-5513页

作者： Ashwin d dhanda Richard WL Lee peter L Collins C Anne McCune department of Liver Medicine University Hospitals Bristol NHS Foundation TrustBS2 8HW BristolUnited Kingdom department of Cellular and Molecular Medicine School of Clinical SciencesUniversity of BristolBS9 1TD BristolUnited Kingdom

Alcohol related costs to health and society are high. One of the most serious complications of alcohol misuse to the individual is the development of alcoholic hepatitis (AH), a clinical syndrome of jaundice and progressive inflammatory liver injury in patients with a history of recent heavy alcohol use. It has a poor outcome and few existing successful therapies. The use of glucocorticoids in patients with severe AH is still controversial and there remains a group of patients with glucocorticoid-resistant disease. However, as our understanding of the pathogenesis of the condition improves there are opportunities to develop new targeted therapies with specific actions to control liver inflammation without having a detrimental effect on the immune system as a whole. In this article we review the molecular mechanisms of AH concentrating on the activation of the innate and adaptive immune response. We consider existing treatments including glucocorticoids, anti-tumor necrosis factor therapy and pentoxifylline and their limitations. Using our knowledge of the disease pathogenesis we discuss possible novel therapeutic approaches. New targets include pro-inflammatory cytokines such as interleukin (IL)-17, chemokines and their receptors (for example IL-8, CXCL9 and CXCR3) and augmentation of anti-inflam- matory molecules such as IL-10 and IL-22. And there is also future potential to consider combination therapy to selectively modulate the immune response and gain control of disease.

关键词： Alcoholic hepatitis Tumour necrosis factor-m Pentoxifylline Interleukins Chemokine receptors

Adherence to surveillance guidelines for dysplasia and colorectal carcinoma in ulcerative and Crohn's colitis patients in the Netherlands

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World Journal of Gastroenterology 2009年第2期15卷 226-230页

作者： Anne F van Rijn Paul Fockens peter d Siersema Bas Oldenburg department of Gastroenterology and Hepatology Academic Medical Center University of Amsterdam Amsterdam 1105AZ The Netherlands department of Gastroenterology and Hepatology University Medical Centre Utrecht Utrecht 3584CX The Netherlands

AIM: To study adherence to the widely accepted surveillance guidelines for patients with long-standing colitis in the Netherlands. METHOdS: A questionnaire was sent to all 244 gastroenterologists in the Netherlands. RESULTS: The response rate was 63%. Of all gastroenterologists, 95% performed endoscopic surveillance in ulcerative colitis (UC) patients and 65% in patients with Crohn's colitis. The American Gastroenterological Association (AGA) guidelines were followed by 27%, while 27% and 46% followed their local hospital protocol or no specific protocol, respectively. The surveillance was correctly initiated in cases of pancolitis by 53%, and in cases of left-sided colitis by 44% of the gastroenterologists. Although guidelines recommend 4 biopsies every 10 cm, less than 30 biopsies per colonoscopy were taken by 73% of the responders. Only 31%, 68% and 58% of the gastroenterologists referred patients for colectomy when low-grade dysplasia, high-grade dysplasia (HGd) or dysplasia Associated Lesion or Mass (dALM) was present, respectively. CONCLUSION: Most dutch gastroenterologists performendoscopic surveillance without following international recommended guidelines. This practice potentially leads to a decreased sensitivity for dysplasia, rendering screening for colorectal cancer in this population highly ineffective.

关键词： Colorectal cancer Crohn's disease dysplasia Guidelines Surveillance Ulcerative colitis

Methyl-β-cyclodextrin enhanced biodegradation of polycyclic aromatic hydrocarbons and associated microbial activity in contaminated soil

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Journal of Environmental Sciences 2012年第5期24卷 926-933页

作者： peter Christie Agri-Environment Branch Agri-Food and Biosciences Institute Newforge Lane Belfast BT9 5PX United Kingdom

The contamination of soils by polycyclic aromatic hydrocarbons （PAHs） is a widespread environmental problem and the remediation of PAHs from these areas has been a major concern. The effectiveness of many in situ bioremediation systems may be constrained by low contaminant bioavailability due to limited aqueous solubility or a large magnitude of sorption. The objective of this research was to evaluate the effect of methyl-β-cyclodextrin （MCd） on bioaugmentation by Paracoccus sp. strain HPd-2 of an aged PAH-contaminated soil. When 10% （W/W） MCd amendment was combined with bioaugmentation by the PAH-degrading bacterium Paracoccus sp. strain HPd-2, the percentage degradation of total PAHs was significantly enhanced up to 34.8%. Higher counts of culturable PAH- degrading bacteria and higher soil dehydrogenase and soil polyphenol oxidase activities were observed in 10% （W/W） MCd-assisted bioaugmentation soil. This MCd-assisted bioaugmentation strategy showed significant increases （p 〈 0.05） in the average well color development （AWCd） obtained by the BIOLOG Eco plate assay, Shannon-Weaver index （H） and Simpson index （λ） compared with the controls, implying that this strategy at least partially restored the microbiological functioning of the PAH-contaminated soil. The results suggest that MCd-aided bioaugmentation by Paracoccus sp. strain HPd-2 may be a promising practical bioremediation strategy for aged PAH-contaminated soils.

关键词： polycyclic aromatic hydrocarbons methyl-β-cyclodextrin biodegradation Paracoccus sp. strain HPd-2 microbial activity

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低温耐磨的CoCrNi多主元合金（英文）

Science Bulletin 2024年第2期 227-236页

作者：任越周青华东鹏黄卓斌李钰龙贾茜 peter Gumbsch Christian Greiner 王海丰刘维民 State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical University Institute for Applied Materials Karlsruhe Institute of Technology IAM-ZM Micro Tribology Center μTC Karlsruhe Institute of Technology Fraunhofer IWM State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

Traditional high strength engineering alloys suffer from serious surface brittleness and inferior wear performance when servicing under sliding contact at cryogenic temperature. Here, we report that the recently emerging CoCrNi multi-principal element alloy defies this trend and presents dramatically enhanced wear resistance when temperature decreases from 273 to 153 K, surpassing those of cryogenic austenitic steels. The temperature-dependent structure characteristics and deformation mechanisms influencing the cryogenic wear resistance of CoCrNi are clarified through microscopic observation and atomistic simulation. It is found that sliding-induced subsurface structures show distinct scenarios at different deformation temperatures. At cryogenic condition, significant grain refinement and a deep plastic zone give rise to an extended microstructural gradient below the surface, which can accommodate massive sliding deformation, in direct contrast to the strain localization and delamination at 273 ***, the temperature-dependent cryogenic deformation mechanisms(stacking fault networks and phase transformation) also provide additional strengthening and toughening of the subsurface material. These features make the CoCrNi alloy particularly wear resistant at cryogenic conditions and an excellent candidate for safety–critical applications.

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Natural End Member Samples of Pyrope and Grossular:A Cathodoluminescence-Microscopy and-Spectra Case Study

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Journal of Earth Science 2018年第5期29卷 989-1004页

作者： Hans-peter Schertl Joana Polednia Rolf d.Neuser Arne P.Willner Ruhr-University Bochum Institute of GeologyMineralogy and GeophysicsD-44780 BochumGermany College of Earth Science&Engineering Shandong University of Science and TechnologyQingdao 266590China Bayerisches Geoinstitut Universitat BayreuthD-95440 BayreuthGermany

Garnet is one of the most significant minerals in metamorphic rocks, that provides key information on prograde, peak-metamorphic and retrograde parts of the pressure-temperature （PT） path. Such results require a detailed knowledge of its different growth domains. For iron-poor compositions, the cathodoluminescence （CL） microscopy is an important and often overlooked method and allows to identify the internal structures of all garnet grains in one thin section within only a few seconds. The advantage of the CL-microscope is to deliver low magnification images in true color, not only of garnet but also, for instance, of other rock forming silicates, carbonates, sulfates, etc., of metamorphic, but also of sedimentary and magmatic origin, using polished thin sections. Internal structures of grossular from Mexico and pyrope from the Italian Alps were characterized and visualized by CL-microscopy. The different growth domains were additionally studied using CL-spectra and electron microprobe （EMP） analysis. Grossular shows a patchy zonation in its core while in mantle and rim zones oscillatory zoning is observed. It contains zones of anomalous birefringence, zones of orange and bluish luminescence and zones lacking luminescence. different but low amounts of the activator elements Mn2＋ and Eu2＋ are responsible for the orange and bluish luminescent domains. Pyrope is also characterized by oscillatory growth zones, shows a dull luminescent core with a change of crystal morphology during growth, and displays an increase of brightness from core towards rim--the outermost rim, however, is lacking luminescence. The different luminescent zones are characterized by different amounts of dy3＋, Tb3＋, Sm3＋ and Sm2＋ as activator elements. Because of slow diffusion rates of activators such as the REEs Sm, dy and Tb, it can be still possible to visualize possible prograde and/or peak pressure stage growth domains of garnet, even if later high temperature events may have homogenized the m

关键词： pyrope grossular cathodoluminescence (CL) oscillatory zoning REE CL-spectra.

Emerging role of dual biologic therapy for the treatment of inflammatory bowel disease

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World Journal of Clinical Cases 2023年第12期11卷 2621-2630页

作者： Matthew d McCormack Natasha A Wahedna david Aldulaimi peter Hawker department of Gastroenterology South Warwickshire NHS Foundation TrustWarwick HospitalWarwick CV345BWUnited Kingdom

Biologic agents have now been used in the management of inflammatory bowel disease(IBd)for many years where experience,expertise and confidence in their use has developed over *** the United Kingdom,there are well established guidelines and recommendations for both single agent biologic treatments,and with combination therapy of a biologic agent with a small molecule agent in maintenance *** recent times,there has been increasing interest and experience using dual biologic therapy(dBT)in IBd,primarily in difficult to treat and refractory cases with high disease ***,published data on use,experience and safety profiles is limited and large-scale studies remain low in number in this developing *** therefore aim to present a summary and review of the available published data in this area to help us better understand the emerging role of dBT in IBd.

关键词： dual biologic therapy Inflammatory bowel disease Crohn’s disease Ulcerative colitis Combination therapy Biologic safety

A systematic literature review on the effectiveness of eurythmy therapy

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Journal of Integrative Medicine 2015年第4期13卷 217-230页

作者： désirée Lotzke peter Heusser Arndt Büssing Quality of Life Spirituality and Coping Institute of Integrative Medicine University of Witten/Herdecke Theory of Medicine Integrative and Anthroposophic Medicine Institute of Integrative MedicineUniversity of Witten/Herdecke

BACKGROUNd：Eurythmy therapy is a movement therapy of anthroposophic medicine that can have effects on a person’s physical body,spirit,and ***：The aim of this publication was to update and summarize the relevant literature on the effectiveness of eurythmy in a therapeutic context since *** STRATEGY：different databases like Pub Med,MEdPILOT,Research Gate,The Cochrane Library,dIMdI,Arthe and also the journal databases der Merkurstab and the European Journal of Integrative Medicine were searched for prospective and retrospective clinical trials in German or English *** CRITERIA：There were no limitations for indication,considered outcome or age of *** EXTRACTION ANd ANALYSIS：Studies were evaluated with regard to their description of the assembly process and treatment,adequate reporting of follow-ups,and equality of comparison groups in controlled ***：Eleven studies met the inclusion *** included two single-arm,non-controlled pilot studies,two publications on the same non-randomized controlled trial and one case study;six further studies referred to a prospective cohort study,the Anthroposophic Medicine Outcome *** of these studies described positives treatment effects with varying effect *** studies were heterogynous according to the indications,age groups,study design and measured *** methodological quality of the studies varied *** were no clear improvements since 2008,when the recommendations were published in the fi rst ***：Eurythmy seems to be a benefi cial add-on in a therapeutic context that can improve the health conditions of affected *** methodologically sound studies are needed to substantiate this positive impression.

关键词： eurythmy therapy mind-body and relaxation techniques anthroposophy review

Quantitative characterization of polyacrylamide–shale interaction under various saline conditions

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Petroleum Science 2017年第3期14卷 586-596页

作者： Samyukta Koteeswaran Jack C.Pashin Josh d.Ramsey peter E.Clark School of Chemical Engineering Oklahoma State UniversityStillwater OK 74078 USA Boone Pickens School of Geology Oklahoma State University Stillwater OK 74078 USA

Interaction of polymer-containing injected fluids with shale is a widely studied phenomenon, but much is still unknown about the interaction of charged polyacrylamides such as anionic and cationic polyacrylamides with shale. The nature of interaction of charged polyacrylamides with shale is not well understood, especially from the perspective of assessing the potential for polyacrylamides to cause formation damage. Zeta potential and rheological measurements were made for Chattanooga and Pride Mountain shales suspended in polyacrylamide solutions with and without inorganic salts and tetramethyl ammonium chloride（TMAC）. The change in zeta potential and viscosity with time was recorded. The magnitude of decrease in the absolute value of zeta potential with time is indicative of adsorption of polymer on the surface of shale and serves as a measure of the extent of polymer interaction with shale. The salts that were used in this study are potassium chloride（KCl）, sodium chloride（Na Cl）. This study quantified the interaction of anionic and cationic polyacrylamide with different North American *** the experimental results, it was determined that the polyacrylamides can interact strongly with shale, particularly the cationic polyacrylamide. The objective of this study was to determine the extent of interaction of anionic and cationic polyacrylamide with each shale sample in the presence of additives such as salts.

关键词： Anionic and cationic polyacrylamides Chattanooga shale Pride Mountain shale Zeta potentialSlurry rheology