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Experimental investigation of fluidized-bed reactor performance for oxidative coupling of methane

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Journal of Natural Gas Chemistry 2012年第5期21卷 534-543页

作者： s.jašo s.sadjadi H.R.Godini U.simon s.Arndt O.Görke A.Berthold H.Arellano-Garcia H.schubert R.schomäcker G.Wozny Chair of Process Dynamics and Operation Berlin Institute of TechnologyStraβe des 17 Juni 135Sekr.KWT910623 BerlinGermany Institute for Material science and Technologies Berlin Institute of TechnologyHardenbergstr.4010623 BerlinGermany Institute for Technical Chemistry Berlin Institute of TechnologyStraβe des 17 Juni 12410623 BerlinGermany

Performance of the oxidative coupling of methane in fluidized-bed reactor was experimentally investigated using Mn-Na2WO4/siO2,La2O3/CaO and La2O3-srO/CaO *** catalysts were found to be stable,especially Mn-Na2WO4/siO2 *** effect of sodium content of this catalyst was analyzed and the challenge of catalyst agglomeration was addressed using proper catalyst composition of 2%Mn2.2%Na2WO4/*** other two catalysts,the effect of Lanthanum-strontium content was analyzed and 10%La2O 3-20%srO/CaO catalyst was found to provide higher ethylene yield than La2O3/CaO ***,the effect of operating parameters such as temperature and methane to oxygen ratio were also *** highest ethylene and ethane （C2） yield was achieved with the lowest methane to oxygen ratio around 2.40.5% selectivity to ethylene and ethane and 41% methane conversion were achieved over La2O3-srO/CaO catalyst while over Mn-Na2WO4 /siO2 catalyst,40% and 48% were recorded,***,the consecutive effects of nitrogen dilution,ethylene to ethane production ratio and other performance indicators on the down-stream process units were qualitatively discussed and Mn-Na2WO4/siO2 catalyst showed a better performance in the reactor and process scale analysis.

关键词： oxidative coupling of methane (OCM) fluidized-bed reactor catalyst stability

Matched pair analysis of the effect of longer hypothermic machine perfusion time on kidney transplant outcomes

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World Journal of Transplantation 2024年第3期14卷 95-101页

作者： Carlos Verdiales Luke Baxter Hyun ja Lim Gavin Beck Michael A Moser Department of surgery University of SaskatchewanSaskatoonSaskatchewan S7N 0W8Canada College of Medicine University of SaskatchewanSaskatoonSaskatchewan S7N 0W8Canada Canada and Northern Ontario school of Medicine Thunder BayOntario P7B 5E1Canada Department of Community Health and Epidemiology University of SaskatchewanSaskatoonSaskatchewan S7N 0W8Canada

BACKGROUND Hypothermic machine perfusion(HMP)has demonstrated benefits in terms of early kidney transplant function compared to static cold *** longer preservation times have shown detrimental effects,a previous paired study indicated that longer pump times(the second kidney in a pair)might lead to improved *** To revisit the prior paired study's somewhat unexpected results by reviewing our program's *** A total of 61 pairs of transplant recipients who received kidneys from the same donor(2012-2021)were *** were divided into two groups depending on whether they were transplanted first(K1)or second(K2).Therefore,the patients in each pair had identical donor characteristics,except for time on the *** analyses included Kaplan-Meyer analysis and paired tests,including McNemar's test,student's paired t-test,or Wilcoxon's test,as *** The two groups of recipients had similar demographics(age,body mass index,diabetes,time on dialysis,sensit-ization and retransplants).Cold ischemic times for K1 and K2 were 8.9(95%CI:7.9,9.8)and 14.7 hours(13.7,15.8)(Psy-proven acute rejection at 1 year(P=0.015).Delayed graft function was less common in K2,12/61(20%)than in K1,20/61(33%)(P=0.046).Finally,K2 showed a higher graft survival than K1(P=0.023).CONCLUsION Our results agree with a previous study that suggested possible advantages to longer pump *** studies should encourage further research into HMP's potential anti-inflammatory effect.

关键词： Hypothermic machine perfusion Paired kidney study Early acute rejection

New anti-mesenteric delta-shaped stapled anastomosis: Technical report with short-term postoperative outcomes in patients with Crohn’s disease

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World Journal of Gastrointestinal surgery 2024年第8期16卷 2592-2601页

作者： Jong Lyul Lee Yong sik Yoon Hyun Gu Lee Young Il Kim Min Hyun Kim Chan Wook Kim In ja Park seok-Byung Lim Chang sik Yu Division of Colon and Rectal surgery Department of SurgeryUniversity of Ulsan College of MedicineAsan Medical CenterSeoul 05505South Korea Department of surgery Gangdong Kyung Hee University HospitalSeoul 05278South Korea

BACKGROUND Medical treatment for Crohn’s disease(CD)has continuously improved,which has led to a decrease in surgical recurrence *** these advancements,25%of patients will undergo repeat intestinal *** of CD com-monly occurs on the mesentery side of the anastomosis *** To compare the new anti-mesenteric side-to-side delta-shaped stapled anasto-mosis(DsA)with the conventional stapled functional end-to-end anastomosis(CsA).METHODs This retrospective study included CD patients who underwent ileo-ileal or ileo-colic anastomosis between january 2020 and December *** DsA technique employed a stapler to maintain the concept of anti-mesentery side-to-side ana-stomosis by performing a 90°vertical closure of the open window compared with the CsA *** the corner where the open window is closed,the DsA avoids forming a pouch and creates an anastomosis resembling a delta shape within the intestinal *** compared demographics,preoperative condition,operative findings,and operative outcomes for the two *** The study included 175 patients,including 92 in the DsA group and 83 in the CsA *** two groups were similar in baseline characteristics,preoperative medical treatment,and operative findings except for the Montreal classification *** 30-days postoperative complication rate was signi-ficantly lower in the DsA group compared with the CsA group(16.3%vs 32.5%,P=0.009).Ileus incidence was significantly lower in the DsA group than in the CsA group(4.3%vs 14.5%,P=0.033),and the hospital stay was shorter in the DsA group than in the CsA group(5.67±1.53 days vs 7.39±3.68 days,P=0.001).CONCLUsION The DsA technique was feasible and showed comparable postoperative outcomes with lower short-term complic-ations compared with the CsA *** studies on CD recurrence and long-term complications are warranted.

关键词： Crohn’s disease surgery Anastomosis Complication Recurrence

Mechanical Behaviour of Composite Bioactive Bone Cements Consisting of Two Different Types of surface Treated Hydroxyapatite as Filler

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Journal of Wuhan University of Technology(Materials science) 2005年第B12期20卷 10-12页

作者： s Deb ja Roether Department of Biomaterials King's College London School of Dentistry at the Guy's King's & St Thomas Hospital Guy's Tower Guy's Hospital London Bridge London SE 1 9RT UK

Bioactive bone cements based on a paste-paste system for orthopaedic applications were developed consisting of hydroxyapatite （ HA ） filler panicles in a methacrylate matrix comprising urethane dimethacrylate （ UDMA ） and triethylene glycol dimethacrylate （ TEGDMA ）. To improve the interface between inorganic filler and organic matrix the HA panicles were subjected to two different surface treatment methods, using polyacrylic acid （PAA） and γ-methacryloxy propyl trimethoxy silane （γMPs）. The aim of the present study was to determine the influence of surface treatment and the inclusion of multifunctional methacrylates on the mechanical properties, namely 3-point flexural strength （Fs） and fracture toughness of the cements and the effect of ageing in simulated body fluid. Comparing the mechanical properties of the two cements, the γMPs- HA cement showed that the fracture toughness of the experimental bone cements were significantly greater （ p 〈 0.001） compared to that of the PMMA cement, whereas PAA-HA containing cement had strength vollues around 20% lower. Interestingly, PAA was found to be more effective in improving the interface as the PAA treated HA cement （ UTHAPPA ） maintained its strength on immersion in sBF, suggesting that PAA provided a coupling, which was less sensitive to moisture, a similar trend was also observed with the inclusion of the carboxyl containing multifunctional methacrylates.

关键词： bioactive bone cements coupling agents composites polyacrylic acid

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光纤通信技术在民航通信系统中的应用研究

通信电源技术 2024年第9期41卷 187-189页

作者：贾茹中国民航东北地区空中交通管理局辽宁沈阳110000

随着全球民航业的快速发展,人们对通信系统的需求日益增长,特别是在信息传输的实时性、可靠性、安全性以及抗干扰素力等方面。光纤通信技术以其高速、高带宽、抗干扰性强等优势,广泛应用于民航通信系统。文章旨在分析民航通信系统的需求... 详细信息

随着全球民航业的快速发展,人们对通信系统的需求日益增长,特别是在信息传输的实时性、可靠性、安全性以及抗干扰素力等方面。光纤通信技术以其高速、高带宽、抗干扰性强等优势,广泛应用于民航通信系统。文章旨在分析民航通信系统的需求,探讨光纤通信技术在民航通信中的应用现状,并提出光纤通信技术与民航通信系统融合的策略,以期为民航通信系统的优化与升级提供参考。

关键词：光纤通信技术民航通信系统系统优化与升级技术融合

Non-invasive investigation of inflammatory bowel disease

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World Journal of Gastroenterology 2001年第4期7卷 460-465页

作者： ja Tibble IBjarnason Department of Medicine GuysKings.St Thomass Medical SchoolBessemer RoadLondon SE5 9

The assessment of inflammatory activity in intestinal disease in man can be done using a variety of different techniques. These range from the use of non-invasive acute phase inflammatory markers measured in plasma such as C reactive protein (CRP) and the erythrocyte sedimentation rate (EsR) (both of which give an indirect assessment of disease activity) to the direct assessment of disease activity by intestinal biopsy performed during endoscopy in association with endoscopic scoring systems. Both radiology and endoscopy are conventional for the diagnosis of inflammatory bowel disease (IBD). However these techniques have severe limitations when it comes to assessing functional components of the disease such as activity and prognosis. Here we briefly review the value of two emerging intestinal function tests. Intestinal permeability, although ideally suited for diagnostic screening for small bowel Crohn's disease, appears to give reliable predictive data for imminent relapse of small bowel Crohn's disease and it can be used to assess responses to treatment. More significantly it is now clear that single stool assay of neutrophil specific proteins (calprotectin, lactoferrin) give the same quantitative data on intestinal inflammation as the 4 day faecal excretion of 111Indium labelled white cells. Faecal calprotectin is shown to be increased in over 95% of patients with IBD and correlates with clinical disease activity. It reliably differentiates between patients with IBD and irritable bowel syndrome. More importantly, at a given faecal calprotectin concentration in patients with quiescent IBD, the test has a specificity and sensitivity in excess of 85% in predicting clinical relapse of disease. This suggests that relapse of IBD is closely related to the degree of intestinal inflammation and suggests that targeted treatment at an asymptomatic stage of the disease may be indicated.

关键词： Biological Markers Feces Humans Inflammatory Bowel Diseases Intestinal Mucosa

Acute liver failure is frequent during heat stroke

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World Journal of Gastroenterology 2008年第1期14卷 158-159页

作者： JM Garcin ja Bronstein s Cremades P Courbin F Cointet Clinique médicale hpital d'instruction des armées Bégin F 94163 Saint Mandé France service de pathologie digestive hpital d'instruction des armées Clermont Tonnerre F 29200 Brest France

Acute liver failure （ALF） is relatively frequent during heat stroke （Hs）. This risk must be emphasized, because its inddence is higher than is usually thought. In a recent study by Weigand et al, two cases were reported in which liver failure was the leading symptom. We have confirmed their conclusion in a study of 25 cases of Hs with ALF, compared with 25 other cases without ALE Moreover, we observed that hypophosphatemia on admission could predict occurrence of ALF during Hs. As for clinical and other biological parameters, phosphatemia should be monitored for at least 3 d in all cases of Hs, even when it is thought to be mild.

关键词： Heat stroke, Hypophosphatemia Liver failure

Nuclear Planetology:Especially Concerning the Moon and Mars

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Research in Astronomy and Astrophysics 2012年第10期12卷 1313-1380页

作者： Kyeong ja Kim Nobuyuki Hasebe Korea Institute of Geoscience and Mineral Resources Daejeon305-350 Korea Research Institute for science and Engineering Waseda UniversityShinjukuTokyo 169-8555 Japan

To approach basic scientific questions on the origin and evolution of plan- etary bodies such as planets, their satellites and asteroids, one needs data on their chemical composition. The measurements of gamma-rays, X-rays and neutrons emit- ted from their surface materials provide information on abundances of major elements and naturally radioactive gamma-ray emitters. Neutron spectroscopy can provide sen- sitive maps of hydrogen- and carbon-containing compounds, even if buried, and can uniquely identify layers of carbon-dioxide frost. Nuclear spectroscopy, as a means of compositional analysis, has been applied via orbital and lander spacecraft to extrater- restrial planetary bodies： the Moon, Venus, Mars, Mercury and asteroids. The knowl- edge of their chemical abundances, especially concerning the Moon and Mars, has greatly increased in recent years. This paper describes the principle of nuclear spec- troscopy, nuclear planetary instruments carried on planetary missions so far, and the nature of observational results and findings of the Moon and Mars, recently obtained by nuclear spectroscopy.

关键词： nuclear planetology: planetary remote sensing -- elemental mapping --nuclear science payloads -- chemical abundance

Multirange Fractal Analysis on the Negative Correlation between Fractal Dimension of Fractured surface and Toughness of Materials

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Journal of Materials science & Technology 1996年第4期12卷 318-320页

作者： Lung, CW Jiang, ja Zhang, CH International Centre for Materials Physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

Applying the concept of multirange fractals, a new explanation to the Williford's multifractal curve on the relationship of fractal dimension with fracture properties in materials has been given. It shows the importance of factorizing out the effect of fractal structure from other physical causes and separating the appropriate range of scale from multirange fractals.

关键词： Fracture