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Effect of successive sprays on liquid distribution in fluidized beds

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Particuology 2021年第1期19卷 17-24页

作者： Cedric Briens Liliana Pardo reyes Franco Berruti Jennifer McMillan Institute for Chemicals and Fuels from Alternative Resources Western University22312 Wonderland Rd.IldertonONN0M 2A0Canada Edmonton Research Centre Syncrude Canada Ltd942117th AveEdmontonABT6N 1H4 Canada

In processes such as Fluid Coking^(™),agglomerate formation should be minimized since it reduces the yield of valuable products,and degrades operability because of the fouling of *** experimental model,consisting of an aqueous solution of gum arabic with a dye,has been successfully developed to simulate the formation of agglomerates in the Fluid Coking^(™)process,where bitumen is sprayed into a fluidized bed of coke particles The particles wetted by a spray could be predicted by assuming that all the particles in the wake of bubbles formed from the tip of the spray jet have been wetted by the injected *** transfer of liquid from particles wetted with the spray to dry bed particles was relatively ineffective,as the number of wet particles increased by only 50%.With successive liquid injections,the proportion of the liquid trapped in agglomerates increases in latter injections:large agglomerates from earlier injections accumulate above the grid and are carried by gas bubbles into the spray jet cavity,where they seed fresh agglomerates.

关键词： Fluidized bed Liquid injection Agglomerate formation Fluid Coker

复合因素急性应激诱导肠道屏障功能障碍及其作用机制研究

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陆军军医大学学报 2024年第1期46卷 73-83页

作者：林启运候鹏飞郎和东张钧陈卡易龙糜漫天陆军军医大学(第三军医大学)军事预防医学系军队营养与食品安全研究中心重庆市医学营养研究中心重庆市营养与健康重点实验室重庆400038

目的研究复合因素急性应激对肠道屏障功能的影响,并探索相关作用机制。方法20只7~8周龄的雄性C57BL/6小鼠(体质量20~22 g),用随机数表法分为对照(CON)组和模型(MOD)组,n=10。MOD组小鼠于24 h内先后给予4 h休息、15 h的睡眠剥夺、3 h的噪... 详细信息

目的研究复合因素急性应激对肠道屏障功能的影响,并探索相关作用机制。方法20只7~8周龄的雄性C57BL/6小鼠(体质量20~22 g),用随机数表法分为对照(CON)组和模型(MOD)组,n=10。MOD组小鼠于24 h内先后给予4 h休息、15 h的睡眠剥夺、3 h的噪音(120 dB)/闪光(2000±500 lx)和2 h的强迫游泳运动(水温26±1℃、水深45 cm),建立复合因素急性应激模型;CON组小鼠置于恒温恒湿、正常昼夜节律的无噪音环境中不做任何处理。MOD组小鼠强迫游泳运动结束后,将小鼠麻醉采血,颈椎脱臼处死并取材。通过免疫酶联吸附实验试剂盒检测血清肠损伤标志物,HE染色法检测结肠组织形态变化,PAS染色检测肠道杯状细胞数目,免疫荧光、免疫组化和RT-qPCR法检测结肠组织屏障功能和炎症因子相关蛋白及基因表达,16S rRNA技术分析小鼠肠道菌群变化。结果与CON组比较,MOD组小鼠血清肠道损伤标志物脂多糖(Lipopolysaccharide,LPS)、肠脂肪酸结合蛋白(Intestinal fatty acid binding protein,I-FABP)、连蛋白(Zonulin)明显升高(P<0.05);HE染色显示MOD组小鼠肠道组织损伤明显;免疫荧光染色和RT-qPCR结果显示机械屏障相关分子紧密连接蛋白-1(Zona occludens 1,ZO-1)、闭合蛋白(Occludin)表达显著降低(P<0.05),免疫组化和PAS染色提示化学屏障相关杯状细胞数目及黏蛋白2(mucin2,Muc-2)、抗菌肽再生胰岛衍生蛋白3γ(regenerating islet derived-3γ,Reg3γ)、再生胰岛衍生蛋白3β(regenerating islet derived-3β,Reg3β)显著降低(P<0.05);肠道菌群β多样性显著改变,有害菌拟杆菌门、脱硫弧菌门显著增加,有益菌瘤胃球菌科、丹毒丝菌(norank_f_Erysipelotrichaceae)属、孪生球菌(Gemella)属、丹毒丝菌(Erysipelotrichaceae)属显著减少(P<0.05);炎症相关肿瘤坏死因子α(tumor necrosis factor,TNF-α)、白细胞介素6(interleukin-6,IL-6)以及活性氧(reactive oxygen species,ROS)水平均显著增加(P<0.05)。结论复合因素急性应激显著诱导小鼠肠道损伤和肠屏障功能障碍。

关键词：复合因素急性应激肠道屏障机械屏障化学屏障微生物屏障

Modeling of environmental influence in structural health assessment for reinforced concrete buildings

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 295-306页

作者： ka-Veng Yuen Sin-Chi Kuok Department of Civil and Environmental Engineering Univeristy of Macao

One branch of structural health monitoring (SHM) utilizes dynamic response measurements to assess the structural integrity of civil infrastructures. In particular,modal frequency is a widely adopted indicator for structural damage since its square is proportional to structural stiffness. However,it has been demonstrated in various SHM projects that this indicator is substantially affected by fluctuating environmental conditions. In order to provide reliable and consistent information on the health status of the monitored structures,it is necessary to develop a method to filter this interference. This study attempts to model and quantify the environmental influence on the modal frequencies of reinforced concrete buildings. Daily structural response measurements of a twenty-two story reinforced concrete building were collected and analyzed over a one-year period. The Bayesian spectral density approach was utilized to identify the modal frequencies of this building and it was clearly seen that the temperature and humidity fluctuation induced notable variations. A mathematical model was developed to quantify the environmental effects and model complexity was taken into consideration. Based on a Timoshenko beam model,the full model class was constructed and other reduced-order model class candidates were obtained. Then,the Bayesian modal class selection approach was employed to select the one with the most suitable complexity. The proposed model successfully characterizes the environmental influence on the modal frequencies. Furthermore,the estimated uncertainty of the model parameters allows for assessment of the reliability of the prediction. This study not only improves the understanding about the monitored structure,but also establishes a systematic approach for reliable health assessment of reinforced concrete buildings.

关键词： Bayesian inference model selection reinforced concrete building structural health monitoring temperature and humidity effects Timoshenko beam

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高职院校课程思政评估体系构建路径

大学（思政教研） 2024年第9期 129-132页

作者：卡米来马彩梅新疆石河子职业技术学院新疆石河子832099

为了进一步贯彻落实立德树人要求,高职院校须重视课程思政评估体系建设工作,通过健全课程思政评估体系和流程,有效提升课程思政教学质量,将课程思政和专业课教学有机衔接。文章首先简要分析了高职院校构建课程思政评价指标体系的意义、... 详细信息

为了进一步贯彻落实立德树人要求,高职院校须重视课程思政评估体系建设工作,通过健全课程思政评估体系和流程,有效提升课程思政教学质量,将课程思政和专业课教学有机衔接。文章首先简要分析了高职院校构建课程思政评价指标体系的意义、构建依据以及原则,其次重点阐述了高职院校课程思政评估体系建设路径,以期为推动高职院校可持续发展提供参考。

关键词：高职院校课程思政质量评价建设路径

维普期刊数据库博看期刊评论

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老年胃溃疡出血患者再发出血的危险因素分析

中国烧伤创疡杂志 2024年第1期36卷 62-65页

作者：卞卡张巍巍许昌市中心医院消化内科河南许昌461000 许昌市中心医院胃肠外科河南许昌461000

目的探讨分析老年胃溃疡出血患者再发出血的相关危险因素。方法选取2020年3月至2022年3月许昌市中心医院收治的140例老年胃溃疡出血患者作为研究对象,收集患者性别、年龄、发病部位、胃溃疡长径、出血活动度、是否为胃溃疡A1期、是否合... 详细信息

目的探讨分析老年胃溃疡出血患者再发出血的相关危险因素。方法选取2020年3月至2022年3月许昌市中心医院收治的140例老年胃溃疡出血患者作为研究对象,收集患者性别、年龄、发病部位、胃溃疡长径、出血活动度、是否为胃溃疡A1期、是否合并幽门螺杆菌(Hp)感染、有无吸烟史、有无饮酒史、合并其他慢性疾病种类(≤2种、>2种)、是否进行消化内镜治疗、是否长期使用非甾体抗炎药(NSAIDs)等资料,并根据患者止血成功后1个月内是否再发出血将患者分为发生组与未发生组。多因素Logistic回归分析老年胃溃疡出血患者再发出血的危险因素。结果140例老年胃溃疡出血患者均于止血成功后随访1个月,随访过程中21例(150%)患者再发出血,设为发生组;119例(850%)患者未再发出血,设为未发生组。单因素分析结果显示,发生组胃溃疡A1期、Hp感染、未进行消化内镜治疗、长期使用NSAIDs的患者比例均明显高于未发生组(χ^(2)=4269、7381、7580、11836,P=0039、0007、0006、0001);多因素Logistic回归分析结果显示,胃溃疡A1期、Hp感染、未进行消化内镜治疗、长期使用NSAIDs是老年胃溃疡出血患者再发出血的独立危险因素(95%CI为1039~9660、1909~58707、0059~0585、1880~18559,P=0043、0007、0004、0002)。结论胃溃疡A1期、Hp感染、未进行消化内镜治疗、长期使用NSAIDs是老年胃溃疡出血患者再发出血的独立危险因素,临床应根据患者具体情况制定针对性干预措施,以降低再出血发生风险。

关键词：胃溃疡出血老年再出血消化内镜治疗幽门螺杆菌非甾体抗炎药危险因素

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优化高炉炉顶DCS设备在线监测自动控制

冶金信息导刊 2024年第5期61卷 38-40页

作者：庞凯李锦龙河钢集团宣钢公司宣化075100

随着高炉系统的自动化运行率逐渐趋于完善,大大减少了岗位人员工艺流程操作步骤,因此降低设备故障率,提高系统自动化强度尤其重要。

关键词：高炉 DCS控制系统炉顶编码器

Optimal Design of Splitters Attached to Turbo Blower Impeller by RSM

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Journal of Thermal Science 2012年第3期21卷 215-222页

作者： Choon-Man Jang ka-Ram Choi Environmental Engineering Research Division Korea Institute of Construction Technology

This paper describes the optimization of the impeller having splitters for a turbo *** design variables,chord of splitter and pitch of splitter,are introduced to enhance the blower *** pressure and ef-ficiency are selected as an object function,and the optimization of the blower impeller is performed by a response surface method (RSM).Three-dimensional Navier-Stokes equations are introduced to analyze the internal flow of the blower and to find the value of the object function for each *** the shape optimization of the splitters attached to the impeller in the turbo blower,pressure and efficiency at the design flow condition are suc-cessively increased by 5.9 percent and 17.9 percent respectively based on the reference *** higher blower efficiency obtained by optimization of impeller having splitters is mainly caused by reducing the number of im-peller blades and optimal design of splitters in the blade passage while pressure increase keeps almost the same with the reference *** the object function of pressure,pressure increase is obtained at the design and off-design conditions while efficiency keeps higher compared to the reference *** enhancement of blow-er performance is due to the reduction of reverse and circulation flows in the blade passage.

关键词： Turbo Blower Splitter Numerical Simulation Optimal Design Pressure Response Surface Method

经支气管冷冻肺活检后按需手术肺活检对比即刻手术肺活检诊断间质性肺疾病(COLD研究):一项随机对照临床试验

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中华结核和呼吸杂志 2024年第9期47卷 826-826页

作者： kalverda ka Ninaber MK Wijmans L 阳胜朱娅琳肖奎不详中南大学湘雅二医院呼吸与危重症医学科中南大学呼吸疾病研究所湖南省呼吸与危重症疾病临床医学研究中心中南大学呼吸疾病诊疗中心长沙410000

背景:间质性肺疾病(ILD)的充分诊断对于临床决策和预后非常重要。大多数ILD患者可通过对临床和放射学数据的评估做出准确诊断,但还有相当一部分患者仍需进行肺活检。手术肺活检(SLB)是获取组织的最常用方法,但其发病率甚至死亡率都很高... 详细信息

背景:间质性肺疾病(ILD)的充分诊断对于临床决策和预后非常重要。大多数ILD患者可通过对临床和放射学数据的评估做出准确诊断,但还有相当一部分患者仍需进行肺活检。手术肺活检(SLB)是获取组织的最常用方法,但其发病率甚至死亡率都很高。最近,临床引入了经支气管冷冻肺活检,其不良反应较SLB少,但诊断率低于SLB。本研究旨在比较两种诊断策略:阶梯策略(经支气管冷冻肺活检,如果冷冻活检获得的信息不够,再进行SLB)与即刻SLB策略。方法:COLD研究是一项在荷兰6家医院开展的多中心、随机对照临床试验。该研究纳入了经多学科团队讨论评估有肺活检指征的ILD患者。以1∶1的比例将患者随机分配到阶梯策略或即刻SLB策略中,并从首次手术开始随访12周。本研究的治疗对患者、临床医生和病理学家均未设盲。主要研究终点是非预期的胸管引流,定义为经支气管冷冻肺活检后需要胸管引流,或SLB后胸管引流时间延长(>24 h)。次要研究终点是诊断率、住院时间、术后疼痛评分和严重不良事件,其中,严重不良事件包括研究期间患者出现死亡、危及患者生命、患者需再次入院或患者住院时长增加[经支气管镜检查超过2 d(1个夜晚),SLB超过4 d(3个夜晚)]。研究进行了改良的意向治疗分析。研究已在荷兰试验注册中心(NL7634)注册,现已结束。结果:在2019年4月8日至2021年10月24日期间,122例ILD患者接受了研究评估;55例患者被随机分配至阶梯组(n=28)或即刻SLB组(n=27);即刻SLB组有3例患者被排除。阶梯组的28例患者中有3例发生意外胸管引流(11%,95%CI:4%~27%),而即刻SLB组24例患者中有11例(46%,95%CI:2%~65%)在24 h内无法拔除胸管,绝对风险降低35%(11%~56%,P=0.0058)。在阶梯策略中,仅经支气管冷冻肺活检后的多学科团队诊断率为82%(64%~92%),在经支气管冷冻肺活检不确定后进行后续SLB时,诊断率增至89%(73%~96%)。在即刻SLB策略中,多学科团队的诊断率为88%(69%~97%)。阶梯组的总住院时间为1 d(IQR 1~1),而即刻SLB组为5 d(IQR 4~6)。阶梯组发生了1起(4%)严重不良事件,而即刻SLB组发生了12起(50%)严重不良事件。结论:在ILD诊断中,如果需要对肺组织进行评估,那么诊断策略应从经支气管冷冻肺活检开始,然后在经支气管冷冻肺活检不能得出诊断结论时进行SLB,这样似乎可显著减轻患者负担,缩短住院时间,且诊断率与即刻SLB相似。

关键词：间质性肺疾病支气管镜检查多学科团队患者负担病理学家肺活检临床决策诊断策略

The Beauty of Being a Variant： H2A.Z and the SWR1 Complex in Plants

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Molecular Plant 2009年第4期2卷 565-577页

作者： Rosana March-Diaz Jose C. reyes Andalusian Center for Molecular Biology and Regenerative Medicine (CABIMER) CSIC Americo Vespucio s/n E-41092 Sevilla Spain

Numerous studies have shown that the nucleosome is a dynamic structure that strongly influences gene expression. Dynamism concerns different nucleosomal characteristics, including position, posttranslational modifications, and histone composition. Thus, within the nucleosome, canonical histones can be exchanged by histone variant proteins with specific functions--a process known as ‘histone replacement＇. The histone variant H2A.Z has an important function in transcription and, during the last few years, its role in plant development and immune response has become evident. Compiling genetic and biochemical studies from several laboratories has revealed that plants contain a multiprotein complex, similar to the SWR1/SRCAP complex from yeast and animals, involved in H2A.Z deposition. Despite intense research in different organisms, the mechanism by which H2A.Z influences transcription is still unknown. However, recent results from Arabidopsis have shown a strong inverse correlation between H2A.Z and DNA methylation, suggesting that H2A.Z might protect genes from silencing.

关键词： Chromatin structure and remodeling epigenetics gene regulation floral induction.