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Standards and methods for dent assessment and failure prediction of pipelines:A critical review

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Petroleum Science 2022年第6期19卷 3029-3045页

作者： Jian Zhao Yun-Rong Lv Y.frank Cheng Dept.of Mechanical&Manufacturing Engineering University of CalgaryAlbertaT2N 1N4Canada Guangdong Provincial Engineering Technology Research Center of Petrochemical Corrosion and Safety Guangdong University of Petrochemical TechnologyMaomingGuangdongChina

Dent,a common mechanical damage on pipelines,is associated with a significant local plastic *** can cause pipeline failures,especially when they are combined with other types of defects such as gouges,fatigue,corrosion,and *** this work,a systematic review of various assessment methods and standards for pipeline dents,including the combination of a dent with other defects,is ***,the methods available today are not sufficiently accurate and reliable to assess pipeline dents,especially the dent-defect *** plain dents on pipelines,both the depthbased criterion and the strain-based criterion are commonly used in *** main problems include inaccuracy and *** a dent combined with other defects,the existing assessment techniques are not mature enough to give reliable *** experimental testing and numerical modeling through finite element(FE)analysis are capable of investigating the influence of dents and dent-defect combinations on burst failure pressure of the pipelines,although an approximation to the reality is still the main difficulty existing in the experimental testing and FE ***,relevant studies on assessment techniques for plain dents,a dent with fatigue and a dent with a single gouge have been common in *** combinations of a dent with corrosion or cracks have been rarely assessed due to complicated mechanisms involving a multi-physics coupling *** of novel assessment methods by integrating mechanical stress and strain,electrochemical reactions and steel metallurgy will be a key topic to accurately assess the dent-defect combinations for improved pipeline integrity.

关键词： Dents Pipelines Assessment techniques Burst failure pressure Dent-defect combinations

Perovskite–A wonder catalyst for solar hydrogen production

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Journal of Energy Chemistry 2021年第6期30卷 325-340,I0008页

作者： Hui Bian Deng Li Junqing Yan Shengzhong(frank)Liu Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationChina Shaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119ShaanxiChina Dalian National Laboratory for Clean Energy China iChEM Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Hydrogen generation via artificial photosynthesis paves a promising way to remit the ever-increasing energy crisis and deteriorative environmental *** all the materials utilized for solar hydrogen production,perovskite has emerged as a rising star due to its superior optoelectronic *** manuscript aims to provide a comprehensive review summarizing the recent inspiring advancements on perovskite-based solar hydrogen production systems,including the particulate photocatalysis,photoelectrochemical cells,and photovoltaic-electrocatalytic *** start with a brief introduction of the advantages of perovskites for solar hydrogen production and the basic principles of the three most prominent solar hydrogen production *** representative progresses in this field are then detailed with a special emphasis on the strategies to improve the efficiency and the stability of the ***,challenges and opportunities for the further development of the PVK-based solar hydrogen production systems are presented with perspective given on outlook,performance,cost and stability.

关键词： Perovskite Solar hydrogen production Photocatalysis Photoelectrocatalysis Photovoltaic-electrocatalysis

A new perspective is needed for positive selection of germinal center B cells with higher-affinity B cell receptors

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Cellular & Molecular Immunology 2022年第2期19卷 145-146页

作者： Timo Gaber frank Buttgereit Department of Rheumatology and Clinical Immunology Charité-Universitätsmedizin Berlincorporate member of Freie Universität Berlin and Humboldt Universität zu BerlinBerlinGermany.

In a recent issue of Nature Immunology,Chen et *** differential expression signatures of metabolic programs within the germinal center(GC)compartment to distinguish GC B cells from different zones[1].Furthermore,they identified an important role of oxidative phosphorylation(OXPHOS)in the process of positive selection of B cells with higher-affinity B cell receptors(BCRs)in *** are inducible secondary lymphoid microanatomical structures that provide niches for B cells to capture and present antigens in the light zone(LZ)and to undergo clonal expansion and BCR somatic hypermutation(SHM)in the dark zone(DZ)*** migration of activated GC B cells between the LZ and DZ is assumed to result in positive selection of clones with higher-affinity B cell antigen *** clones are characterized by accelerated cell division,suggesting a genomic program activated by BCR and CD40 signaling[2].

关键词： center positive signature

Safety of anti-tumor necrosis factor therapy in inflammatory bowel disease

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World Journal of Gastroenterology 2009年第17期15卷 2067-2073页

作者： frank Hoentjen Ad A van Bodegraven Department of Gastroenterology VU University Medical Center PO Box 7057 1007 MB Amsterdam The Netherlands

Inflammatory bowel disease (IBD), in particular Crohn's disease refractory to conventional therapy, fistulizing Crohn's disease and chronic active ulcerative colitis, generally respond well to anti-tumor necrosis factor (TNF) therapy. However, serious side effects do occur, necessitating careful monitoring of therapy. Potential side effects of anti-TNF therapy include opportunistic infections, which show a higher incidence when concomitant immunosuppression is used. Furthermore, antibody formation against anti-TNF is associated with decreased efficacy and an increased frequency of infusion reactions. The hypothesis of a slightly increased risk of lymphomas in IBD patients treated with anti TNF-therapy is debatable, since most studies lack the specific design to properly address this issue. Alarmingly, the occurrence of hepatosplenic T-cell lymphomas coincides with combined immunosuppressive therapy. Despite the potential serious side effects, anti-TNF therapy is an effective and relatively safe treatment option for refractory IBD. Future research is needed to answer important questions, such as the long-term risk of malignancies, safety during pregnancy, when to discontinue and when to switch anti-TNF therapy, as well as to determine the balance between therapeutic and toxic effects.

关键词： Anti-tumor necrosis factor Biologics Inflammatory bowel diseases Crohn's disease Infliximab

Fault Diagnosis of Nonlinear Systems Using Structured Augmented State Models

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International Journal of Automation and computing 2007年第2期4卷 141-148页

作者： Jochen Aβfalg frank Allgwer Robert Bosch GmbH Corporate Sector Research70442 StuttgartGermany University of Stuttgart Institute for Systems Theory and Automatic Control70550 StuttgartGermany

This paper presents an internal model approach for modeling and diagnostic functionality design for nonlinear systems operating subject to single- and multiple-faults. We therefore provide the framework of structured augmented state models. Fault characteristics are considered to be generated by dynamical exosystems that are switched via equality constraints to overcome the augmented state observability limiting the number of diagnosable faults. Based on the proposed model, the fault diagnosis problem is specified as an optimal hybrid augmented state estimation problem. Sub-optimal solutions are motivated and exemplified for the fault diagnosis of the well-known three-tank benchmark. As the considered class of fault diagnosis problems is large, the suggested approach is not only of theoretical interest but also of high practical relevance.

关键词： Fault diagnosis nonlinear systems hybrid estimation.

Breakthrough in the challenging P450-catalyzed chemoenzymatic synthesis of C14-functionalized steroids

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中国科学:化学英文版 2023年第9期66卷 2435-2436页

作者： Manfred T.Reetz frank Hollmann Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 145480 MülheimGermany Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China Department of Biotechnology Delft Universityvan der Maasweg 92629 HZ DelftNetherlands

Intensive past research has demonstrated that cytochrome P450 monooxygenases are involved in the biosynthesis of numerous natural products and in human metabolism of various pharmaceuticals [1]. This inspired synthetic organic and pharmaceutical chemists to test them as catalysts in the oxidative hydroxylation of steroids. Unfortunately, wildtype P450s generally proved to show low levels of regio-and diastereoselectivity as well as suboptimal activity.

关键词： steroids catalyzed synthesis

A new focus on risk reduction: an ad hoc decision support system for humanitarian relief logistics

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Ecosystem Health and Sustainability 2015年第3期1卷 1-12页

作者： frank Schatter Marcus Wiens frank Schultmann Karlsruhe Instilute of Technology(KIT) Institute for Industrial Production(IIP)HertzstraBe 16Karlsruhe 76187 Germany University of Adelaide EntrepreneurshipCommercialisationand Innovation Centre(ECIC).Level 510 Pulteney StretAdelaideSouth Australia 5005 Australia

Particularly in the early phases of a disaster,logistical decisions are needed to be made quickly and under high pressure for the decision-makers,knowing that their decisions may have direct consequences on the affected society and all future *** risk reduction may be helpful in providing decision-makers with optimal strategies in ***,disasters are characterized by severe uncertainty and complexity,limited knowledge about the causes of the disaster,and continuous change of the situation in unpredicted *** these assumptions,we believe that adequate proactive risk reduction measures are not *** propose strengthening the focus on ad hoc decision support to capture information in almost real time and to process information efficiently to reveal uncertainties that had not been previously ***,we present an ad hoc decision support system that uses scenario techniques to capture uncertainty by future developments of a situation and an optimization model to compute promising decision *** combining these aspects in a dynamic manner and integrating new information continuously,it can be ensured that a decision is always based on the best currently available and processed *** finally,to identify a robust decision option that is provided as a decision recommendation to the decision-makers,methods of multi-attribute decision making(MADM)are *** approach is illustrated for a facility location decision problem arising in humanitarian relief logistics where the objective is to identify robust locations for tent hospitals to serve injured people in the immediate aftermath of the Haiti Earthquake 2010.

关键词： ad hoc decision support humanitarian relief logistics information and communication tecmology multi-criteria decision analysis public safety-critical supply chains robustness scenario techniques

A Season for Hymning and Hawing

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中国翻译 1995年第5期 61-62页

作者： frank trippett

Technically, it begins next week. Actually, itbegan with the epic sigh of relief that could besensed all over the U. S. right after Labor *** before it arrives, Americans always manageto get into autumn. And no wonder. It is easilythe most habitable season of the year. Indeed, autumn deserves a hymn - and ithas received far less tribute than it deserves. true,some mixed notices have come in over the cen-turies. Horace slandered autumn as a "dread" peri-od - "harvest-season of the Goddess of Death."

关键词： A Season for Hymning and Hawing

Blue LED growth from 2 inch to 8 inch

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Science China(Technological Sciences) 2011年第1期54卷 33-37页

作者： frank LU Dong LEE Dan BYRNES Eric ARMOUR & William QUINN Veeco Turbodisc-Somerset

Growth of blue InGaN based LED structures on sapphire wafers from 2 inch to 8 inch in diameter was investigated using the Veeco K465 MOCVD platform. Our results indicate that the same pressure,rotation rate and hydride flows can be used for all wafer sizes. AFM and X-ray studies reveal that all wafer sizes have comparable high-quality crystallinity and defect levels for GaN and InGaN/GaN MQW growth. Although the larger diameter wafers exhibit larger wafer bow due to lattice and thermal mismatch,with proper wafer pocket design,good wavelength and thickness uniformity can be obtained for all wafer sizes.

关键词： GaN InGaN blue LED MOCVD