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Urgent one-stage endoscopic treatment for choledocholithiasis related moderate to severe acute cholangitis: A propensity scorematched analysis
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作者 Yang Zhou Yin-Qiu Zhang +4 位作者 Shuai-Jing Huang Yan Liang Xiao Liang Masoom Wali Ya-Dong Feng 《World Journal of Gastroenterology》 SCIE CAS 2024年第15期2118-2127,共10页
BACKGROUND During emergency endoscopic retrograde cholangiopancreatography(ERCP),the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis(AC)due to choledocholithiasi... BACKGROUND During emergency endoscopic retrograde cholangiopancreatography(ERCP),the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis(AC)due to choledocholithiasis are unclear.AIM To investigate the safety and feasibility of one-stage endoscopic treatment for moderate to severe AC.METHODS We enrolled all patients diagnosed with moderate to severe cholangitis due to common bile duct stones from January 2019 to July 2023.The outcomes were compared in this study between patients who underwent ERCP within 24 h and those who underwent ERCP 24 h later,employing a propensity score(PS)frame-work.Our primary outcomes were intensive care unit(ICU)admission rates,ICU length of stay,and duration of antibiotic use.RESULTS In total,we included 254 patients and categorized them into two groups based on the time elapsed between admission and intervention:The urgent group(≤24 h,n=102)and the elective group(>24 h,n=152).Ninety-three pairs of patients with similar characteristics were selected by PS matching.The urgent ERCP group had more ICU admissions(34.4%vs 21.5%,P=0.05),shorter ICU stays(3 d vs 9 d,P<0.001),fewer antibiotic use(6 d vs 9 d,P<0.001),and shorter hospital stays(9 d vs 18.5 d,P<0.001).There were no significant differences observed in adverse events,in-hospital mortality,recurrent cholangitis occurrence,30-d readmission rate or 30-d mortality.CONCLUSION Urgent one-stage ERCP provides the advantages of a shorter ICU stay,a shorter duration of antibiotic use,and a shorter hospital stay. 展开更多
关键词 Acute cholangitis Endoscopic retrograde cholangiopancreatography one-stage treatment Optimal time
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Security Assurance for One-stage Resection of Left Colon Cancer with Acute Obstruction—Thorough and Prompt Enteral Decompression without Contamination 被引量:12
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作者 彭淑牖 何小伟 +3 位作者 刘颖斌 李江涛 王建伟 钱浩然 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第1期8-10,65,共4页
Objective: Thorough, prompt enteral decompression technique without contamination was de- veloped to ensure safety for emergent colon resection and primary anastomosis. Methods: After isolating the mesentery, the “to... Objective: Thorough, prompt enteral decompression technique without contamination was de- veloped to ensure safety for emergent colon resection and primary anastomosis. Methods: After isolating the mesentery, the “to be resected colon segment” was cut at its lower end, then the proximal cut end was put into a plastic bag which was adhered to one side of the operating table. After releasing the clamp, the content could ?ow into this bag. The operator could squeeze the bowel with two hands by turns, from proximal to farness, and from small bowel to large bowel, until the entire bowel content was fully discharged. Then the upper end of this “to be resected colon segment” was cut, and was removed together with the plastic bag. Results: 31 cases of left colon cancer with acute obstruction were decompressed with this technique. They all recovered smoothly, without anastomosis ?stula. Another 6 cases of hepatic seg- mentectomy with incidental colonectomy were decompressed with this technique and had the same results. This technique was also used in di?erent kinds of acute small intestinal obstruction and gained satisfactory results. Conclusion: This technique could be considered as the preferable choice for intraoperative enteral decompression. 展开更多
关键词 enteral decompression left colon one-stage anastomosis peritoneal contamination
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A Rare Long Term Survival Case of Complete Pentalogy of Cantrell in Adult after One-Staged Surgery
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作者 Hao Hong Nianguo Dong +4 位作者 Mingxing Xie Lin Li Si Chen Wengang Sun Xiaoqing Hu 《Congenital Heart Disease》 SCIE 2021年第5期513-518,共6页
Pentalogy of Cantrell is a rare congenital abnormality.Even with high-quality medical care and staged corrective surgeries in professional hospitals,the mortality rate is still very high and long-term prognosis is poo... Pentalogy of Cantrell is a rare congenital abnormality.Even with high-quality medical care and staged corrective surgeries in professional hospitals,the mortality rate is still very high and long-term prognosis is poor.Survival is largely determined by the complexity and severity of cardiac abnormalities,the efficiency of abdominal wall closure and postoperative complications.A 24-year-old male patient with complete pentalogy of Cantrell was diagnosed.One-stage surgical repair of all abnormalities were completed.The patient recovered well and had been follow-up for 7 years.He has a good cosmetic outcome,with no signs of cardiac dysfunction.No complications were noted. 展开更多
关键词 Pentalogy of cantrell ADULT one-stage surgery
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One-stage revision arthroplasty in a patient with ochronotic arthropathy accompanied by joint infection:A case report
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作者 Xiao-Chao Wang Xiao-Min Zhang +6 位作者 Wan-Ling Cai Zhen Li Chao Ma Yi-Hai Liu Qi-Lian He Tian-Sheng Yan Xue-Wei Cao 《World Journal of Clinical Cases》 SCIE 2022年第25期9036-9043,共8页
BACKGROUND Ochronotic arthropathy(OcA)is a rare disease,which is caused by the accumulation of homogentisic acid in the joint.Patients with OcA have obvious joint pain and the disease progresses rapidly,eventually res... BACKGROUND Ochronotic arthropathy(OcA)is a rare disease,which is caused by the accumulation of homogentisic acid in the joint.Patients with OcA have obvious joint pain and the disease progresses rapidly,eventually resulting in disability.Arthroplasty is an efficacious treatment in patients with OcA.However,when OcA patients have joint infection,is joint replacement an option?In the present report,we performed total knee arthroplasty in a patient with OcA and knee infection under the guidance of one-stage revision theory.CASE SUMMARY A 64-year-old male was referred to our hospital due to severe left knee pain with limited mobility for 2 years.On physical examination,the patient was found to have dark brown pigmentation of the sclera and auricle.Laboratory test results showed elevations in C-reactive protein level(65.79 mg/L)and erythrocyte sedimentation rate(90.00 mm/h).The patient underwent debridement of the left knee joint,during which the cartilage surface of the knee joint was found to be black-brown in color.Bacterial culture of synovial fluid revealed Achromobacter xylosoxidans.We then carried out arthroplasty under the guidance of the theory of one-stage revision.After surgery,the patient’s left knee joint pain disappeared and function recovered without joint infection.CONCLUSION OcA accompanied by joint infection is rare.One-stage revision arthroplasty may be a treatment option for this disease. 展开更多
关键词 Ochronotic arthropathy Arthroplasty one-stage revision ALKAPTONURIA Homogentisic acid Case report
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Should we use similar perioperative protocols in patients undergoing unilateral and bilateral one-stage total knee arthroplasty?
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作者 Artit Laoruengthana Piti Rattanaprichavej +3 位作者 Parin Samapath Bhuwad Chinwatanawongwan Pariphat Chompoonutprapa Krit Pongpirul 《World Journal of Orthopedics》 2022年第1期58-69,共12页
BACKGROUND Bilateral one-stage total knee arthroplasty(BTKA)is now in greater use as an alternative option for patients with bilateral end-stage knee arthropathy.However,postoperative pain and disablement during conva... BACKGROUND Bilateral one-stage total knee arthroplasty(BTKA)is now in greater use as an alternative option for patients with bilateral end-stage knee arthropathy.However,postoperative pain and disablement during convalescence from BTKA,and procedure-related complications have been concerning issues for patients and surgeons.Although some studies reported that BTKA in selected patients is as safe as the staged procedure,well-defined guidelines for patient screening,and perioperative care and monitoring to avoid procedure-related complications are still controversial.AIM To compare the perioperative outcomes including perioperative blood loss(PBL),cardiac biomarkers,pain intensity,functional recovery,and complications between unilateral total knee arthroplasty(UTKA)and BTKA performed with a similar perioperative protocol.METHODS We conducted a retrospective study on consecutive patients undergoing UTKA and BTKA that had been performed by a single surgeon with identical perioperative protocols.The exclusion criteria of this study included patients with an American Society of Anesthesiologists score>3,and known cardiopulmonary comorbidity or high-sensitivity Troponin-T(hs-TnT)>14 ng/L.Outcome measures included visual analogue scale(VAS)score of postoperative pain,morphine consumption,range of knee motion,straight leg raise(SLR),length of stay(LOS),and serum hemoglobin(Hb)and hs-TnT monitored during hospitalization.RESULTS Of 210 UTKA and 137 BTKA patients,those in the BTKA group were younger and more predominately female.The PBL of the UTKA vs BTKA group was 646.45±272.26 mL vs 1012.40±391.95 mL(P<0.01),and blood transfusion rates were 10.48%and 40.88%(P<0.01),respectively.Preoperative Hb and body mass index were predictive factors for blood transfusion in BTKA,whereas preoperative Hb was only a determinant in UTKA patients.The BTKA group had significantly higher VAS scores than the UTKA group at 48,72,and 96 h after surgery,and also had a significantly lower degree of SLR at 72 h.The BTKA group also had a significantly longer LOS than the UTKA group.Of the patients who had undergone the procedure,5.71%of the UTKA patients and 12.41%of the BTKA patients(P=0.04)had hs-TnT>14 ng/L during the first 72 h postoperatively.However,there was no difference in other outcome measures and complications.CONCLUSION Following similar perioperative management,the blood transfusion rate in BTKA is 4-fold that required in UTKA.Also,BTKA is associated with higher pain intensity at 48 h postoperatively and prolonged LOS when compared to the UTKA.Hence,BTKA patients may require more extensive perioperative management for blood loss and pain,even if having no higher risk of complications than UTKA. 展开更多
关键词 Bilateral one-stage total knee arthroplasty Unilateral total knee arthroplasty Blood loss Postoperative pain High-sensitivity Troponin-T Cardiovascular events
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One-Stage Bilateral Total Hip Arthroplasty for Hemophilic Spontaneous Ankylotic Hip: A Case Report
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作者 Mariko Asahi Atsushi Kusaba +2 位作者 Akihiko Maeda Saiji Kondo Takahide Tsuchiya 《Case Reports in Clinical Medicine》 2020年第9期269-274,共6页
Total hip arthroplastys (THAs) for hemophilic spontaneous ankylotic hips are rare. We performed one-stage bilateral THA for hemophilic patient and I would like to report the results of the case. A 61-year-old male had... Total hip arthroplastys (THAs) for hemophilic spontaneous ankylotic hips are rare. We performed one-stage bilateral THA for hemophilic patient and I would like to report the results of the case. A 61-year-old male had been diagnosed with mild hemophilia A as a neonate. He had severe pain in both hips and moderate pain in both knees. His hips were ankylotic and had no mobility. Uncemented simultaneous bilateral THAs were performed under general anesthesia. This case suggests that one-stage THA can be a good option for hemophilic hips, provided that sufficient substitution therapy is used. 展开更多
关键词 Hemophilic Arthropathy one-stage Bilateral THA COMPLICATION
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One-stage urethroplasty with circumferential vascular pedicle preputial island flap for perineal hypospadias
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作者 朱再生 《外科研究与新技术》 2011年第4期268-269,共2页
Objective To report the treatment of perineal hypospadias with one - stage urethroplaty with circumferential vascular pedicle preputial island flap. Methods A circumferential incision was made proximal to the cprona a... Objective To report the treatment of perineal hypospadias with one - stage urethroplaty with circumferential vascular pedicle preputial island flap. Methods A circumferential incision was made proximal to the cprona and the urethral plate to correct chordee. A U - shaped skin incision was then made surrounding the meatus。 展开更多
关键词 one-stage urethroplasty with circumferential vascular pedicle preputial island flap for perineal hypospadias
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高效气提环流式生物脱氮反应器在污水厂扩建改造中的应用
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作者 丛琳 吴楠 +3 位作者 王国彬 王务恒 卫东 王社平 《净水技术》 CAS 2024年第11期170-179,共10页
西北某污水处理厂扩建改造一期工程处理规模为5000m^(3)/d,采用高效气提环流式生物脱氮反应器(DIAB)工艺,所用反应器基于厌氧-缺氧-好氧(AAO)推流式生物反应器与升流式厌氧污泥床(upflow anaerobic sludge bed,UASB)反应器特点进行改良... 西北某污水处理厂扩建改造一期工程处理规模为5000m^(3)/d,采用高效气提环流式生物脱氮反应器(DIAB)工艺,所用反应器基于厌氧-缺氧-好氧(AAO)推流式生物反应器与升流式厌氧污泥床(upflow anaerobic sludge bed,UASB)反应器特点进行改良,由多级环状结构构成,利用三相分离器结构设计实现水、气、污泥分离,利用曝气尾气作为动力来源,实现混合液的无动力回流。总水力停留时间为21 h,其中厌氧区、缺氧区和好氧区停留时间分别为1.5、8.5 h和11 h,混合液悬浮固体(MLSS)质量浓度为5500 mg/L,平均BOD5污泥负荷为0.1 kg BOD5/(kg MLSS·d),混合液回流比为300%。污水厂采用该工艺完成改造运行后实际出水水质可稳定达到一级A标准。扩建工程单位处理成本为0.454元/m^(3)、生物处理区占地面积为0.161 m^(2)/m^(3),与相似规模传统AAO工艺相比较处理成本和占地面积分别减少了24.3%和25.8%,在出水水质、运行成本方面均有明显改善,与相似规模循环式活性污泥(CASS)工艺相比较占地面积相似,但处理成本减少约20%,出水水质优于CASS工艺,尤其在脱氮方面表现出色。DIAB工艺脱氮效率及碳源利用率较高,脱氮效果好,碳源投加及回流设备用电电耗低,适用于土地、工期受限,以及进水低碳氮比条件下污水处理厂的扩建、应急建设。 展开更多
关键词 气提环流式生物脱氮反应器(DIAB) 污水处理 应急扩建改造 生物脱氮 气提环流 一体化反应器
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脉冲气举用自振空气射流研究
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作者 唐川林 夏美丽 +4 位作者 杨凤玲 胡东 程宏贵 唐志英 石密 《流体机械》 CSCD 北大核心 2024年第10期89-95,共7页
为了探究自激振荡空气射流发生机理以及最佳结构参数和运行参数,基于流体自激振荡原理,以Helmholtz共振腔作为物理模型,着重分析了自激振荡脉冲空气射流的关键影响因素;利用FLUENT软件对自激振荡脉冲空气射流内外瞬时流场进行数值模拟,... 为了探究自激振荡空气射流发生机理以及最佳结构参数和运行参数,基于流体自激振荡原理,以Helmholtz共振腔作为物理模型,着重分析了自激振荡脉冲空气射流的关键影响因素;利用FLUENT软件对自激振荡脉冲空气射流内外瞬时流场进行数值模拟,获取其流动特性;通过试验得到了在不同长径比L/d1和不同工作压力下,自激振荡空气射流的压力脉动特性。结果表明,试验结果与数值仿真结果吻合良好;长径比与工作压力共同影响射流脉冲效果,减小工作压力将导致能量交换能力变差,削弱射流振荡效果;当工作压力为0.4 MPa时,射流流速大,剪切层卷吸率高,脉冲效果最好;长径比存在一最佳值,使得射流振荡效果最好,当L/d1=7.5左右时,射流的脉动效果最佳。研究结果可为自振空气射流应用于脉冲气举效率提升提供参考。 展开更多
关键词 气举 脉冲气举 自激振荡 脉冲射流
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二级环流反应器中收缩-膨胀隔板的性能优化
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作者 卢哲 史嘉帧 +2 位作者 郭凯 刘春江 郑龙云 《化学工业与工程》 CAS CSCD 北大核心 2024年第1期125-135,共11页
通过在二级环流反应器两级之间安装具有收缩-膨胀形状的隔板,可以有效减小两级之间的液相回流流量,但同时会增加流体流动阻力。为了在减小液相回流流量的前提下减小流动阻力,本研究对隔板进行优化设计。首先通过模拟计算获得不同隔板下... 通过在二级环流反应器两级之间安装具有收缩-膨胀形状的隔板,可以有效减小两级之间的液相回流流量,但同时会增加流体流动阻力。为了在减小液相回流流量的前提下减小流动阻力,本研究对隔板进行优化设计。首先通过模拟计算获得不同隔板下的压降和液相回流流量,随后对数据进行拟合,得到压降、液相回流流量与结构参数的关联式。计算结果表明当表观气速较小时,隔板宽度对压降影响较大,高度的影响较小。表观气速增大时,隔板高度对压降的影响变大。在所有气速下,隔板宽度是影响液相回流流量的决定因素。最后通过多目标优化,获得了在不同表观气速下最优隔板的Pareto前沿。 展开更多
关键词 收缩-膨胀隔板 优化 二级气升式环流反应器 气液两相流 计算流体力学
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气升式环流反应器在生化处理中的中试试验
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作者 吴振虎 顾镛 +1 位作者 袁方 杨强 《水处理技术》 CAS CSCD 北大核心 2024年第8期98-102,共5页
生化处理是炼油废水处理过程中的关键环节,目前的生化处理工艺以氧化塘、SBR为主,但好氧反应区域存在气液混合不均匀、发泡尺寸较大等问题,进而导致氧气利用率低、能耗高。为提高生化反应效率,缩短曝气时间,本文设计了气升式环流反应器(... 生化处理是炼油废水处理过程中的关键环节,目前的生化处理工艺以氧化塘、SBR为主,但好氧反应区域存在气液混合不均匀、发泡尺寸较大等问题,进而导致氧气利用率低、能耗高。为提高生化反应效率,缩短曝气时间,本文设计了气升式环流反应器(ALR),通过安装微细气泡曝气盘配合曝气环产生分形气泡以强化气-液-固三相传质和混合,将二级生化处理单元中的好氧反应区和沉淀区集成在同一个反应器内,并开展了中试试验。研究对比了ALR和SBR对气浮出水的处理效果,衡量了两者的技术经济性指标。试验结果表明:在ALR与SBR在油含量、COD和氨氮去除效果相当的情况下,ALR的污泥负荷提升了10倍,COD容积负荷提升了5倍;同时,ALR的吨水处理的鼓气量减少了57%,吨水处理占地面积仅为SBR的50%左右,吨水处理的能耗降低了22.9%,解决了传统生化处理工艺占地面积大、能耗高等问题,为未来生化反应器的升级改造提供了重要参考。 展开更多
关键词 生化处理 炼油废水 气升式环流反应器 SBR
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基于压差法的海底气举扬矿装置建模与工作特性分析
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作者 汪志能 邹俊伟 +1 位作者 林伟明 王晓川 《工程科学与技术》 EI CAS CSCD 北大核心 2024年第5期268-276,共9页
气举扬矿装置通过气-液-固三相间动量交换,实现海底矿浆的举升,能长期在泥、水、砂等多相共存的恶劣环境中工作,克服了传统机械泵耐磨性差、密封要求高的缺点,具有极强的市场应用价值和广阔的应用前景。海底气举扬矿装置气-液-固三相力... 气举扬矿装置通过气-液-固三相间动量交换,实现海底矿浆的举升,能长期在泥、水、砂等多相共存的恶劣环境中工作,克服了传统机械泵耐磨性差、密封要求高的缺点,具有极强的市场应用价值和广阔的应用前景。海底气举扬矿装置气-液-固三相力学作用过程极为复杂,传统三相力学平衡方法难以精确建立海底气举扬矿模型,严重影响扬矿装置的设计与过程控制。为了提升扬矿性能,在不考虑气-液-固内部力学作用机理情况下,从气-液-固混合流体整体压降衰减角度建立扬矿装置理论模型。提取扬矿管气-液-固流动单元,分析流动单元与管壁的摩擦损耗特性,建立混合流体的压差模型,并以扬矿管进出口压力为约束条件,形成了扬矿理论模型,突破了常规三相力学建模繁琐难题。在此基础之上,搭建海底气举扬矿实验测试平台,验证了理论模型的可靠性,研究结果表明:1)理论模型与实验值吻合度较高,误差在17.6%范围内;2)增大气体表观速度提高了混合流体压差,却降低了含固率,这可能是因为高进气工况下液流摩擦损耗较大,可采取液流减阻策略提高扬矿性能;3)固体颗粒表观速度随气体表观速度先增加后减小,存在最优气体表观速度使得装置扬矿量最大。研究结论为海底气举扬矿装置多相流动特征分析及装置优化设计提供理论基础与技术支撑。 展开更多
关键词 海底采矿 气举 气-液-固 压差
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气升式浆态床外环流反应器流体力学性能研究
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作者 边清 唐晓津 杨涛 《石油炼制与化工》 CAS CSCD 北大核心 2024年第6期115-121,共7页
针对气含率和浆液循环流速两个关键流体力学参数,系统研究了气升式浆态床外环流反应器的流体力学特性,掌握了气含率与浆液循环流速的变化规律。验证了体积膨胀法、压差法和电导探针法测量气含率的方法准确性。研究了气体分布器结构对气... 针对气含率和浆液循环流速两个关键流体力学参数,系统研究了气升式浆态床外环流反应器的流体力学特性,掌握了气含率与浆液循环流速的变化规律。验证了体积膨胀法、压差法和电导探针法测量气含率的方法准确性。研究了气体分布器结构对气升式浆态床外环流反应器流体力学特性的影响,结果表明开孔向下双环管分布器的综合性能最优。气含率与浆液循环液速之间存在线性关系,建立了预测浆液循环流速的计算式,计算误差基本小于20%。 展开更多
关键词 气升式 浆态床外环流反应器 流体力学 气含率 浆液循环流速
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交错多级内环流反应器气泡分布研究
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作者 潘庆鹏 王伟文 《炼油技术与工程》 CAS 2024年第8期11-14,共4页
环流反应器因其独特的循环特性和高效的传质效率,在生物工程、环境工程和化学工程等领域具有巨大的应用潜力。由于对其的研究聚焦于宏观流体力学行为上,针对气泡直径分布的研究对于反应器的设计优化与规模化放大具有深远意义。借助计算... 环流反应器因其独特的循环特性和高效的传质效率,在生物工程、环境工程和化学工程等领域具有巨大的应用潜力。由于对其的研究聚焦于宏观流体力学行为上,针对气泡直径分布的研究对于反应器的设计优化与规模化放大具有深远意义。借助计算流体力学(CFD)与群体平衡模型(PBM),深入探究交错多级内环流反应器内气泡直径分布。研究发现:上升区和下降区存在明显的气含率差异;各级上升区气含率沿轴向表现出不同的变化趋势;对于下降区,气含率沿着轴向高度的增加而增加;反应器内大气泡(直径11.56~14.98 mm)主要集中在第二级和第三级上升区,较小尺寸的气泡(直径0.67~1.13 mm)主要存在于第一级和第三级下降区的底部。 展开更多
关键词 交错 多级 内环流反应器 气泡分布 气含率 气泡直径 流体动力学 群体平衡模型
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Simultaneous type III congenital esophageal atresia and patent ductus arteriosus in a low-weight patient: A case report
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作者 Yong-Yu Ma Jun-Ru Chen +3 位作者 Shi-Wu Yang Shu-Yu Wang Xin Cao Jun Wu 《World Journal of Clinical Cases》 SCIE 2024年第3期560-564,共5页
BACKGROUND We report a low-birth-weight child(1.8 kg)with neonatal type III congenital esophageal atresia(CEA)combined with symptomatic patent ductus arteriosus(PDA).After comprehensive evaluation,esophageal anastomos... BACKGROUND We report a low-birth-weight child(1.8 kg)with neonatal type III congenital esophageal atresia(CEA)combined with symptomatic patent ductus arteriosus(PDA).After comprehensive evaluation,esophageal anastomosis was performed on postnatal day 11 after excluding surgical contraindications,and arterial catheter ligation was performed at the same time.Concurrent surgery for CEA combined with PDA has not been clearly reported in the literature.CASE SUMMARY We report a 6-day-old female child with type III CEA and PDA.The patient presented with foam at the mouth after birth,cough and shortness of breath after feeding.At another hospital,she was considered to have neonatal pneumonia,neonatal jaundice and congenital heart disease and transferred to our hospital.After iodine oil radiography of the esophagus and echocardiography we con-firmed diagnosis of CEA and PDA.The diameter of the PDA was 8 mm,with obvious left to right shunting.We performed right rear extrapleural orificium fistula ligation and esophageal anastomosis,and ligation of PDA via left axilla straight incision after 5 d of hospitalization.The operations were successful,and the incision healed after 12 d,and the patient was discharged.We re-examined the patient 1 mo after surgery.She did not vomit when she ate rice flour.Esophageal angiography showed no stricture of the anastomotic stoma.The patient weighed 3.2 kg.CONCLUSION For CEA patients with multiple risk factors,comprehensive,timely and accurate diagnosis and evaluation,and early treatment may improve prognosis. 展开更多
关键词 Congenital esophageal atresia Patent ductus arteriosus Low weight one-stage operation Case report
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导流筒结构对气升式反应器传质性能的影响研究
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作者 李亮 郝润秋 +2 位作者 郝亚超 师晓光 张成凯 《化学工业与工程》 CAS CSCD 北大核心 2024年第1期144-150,共7页
气升式环流反应器广泛应用于化工、环境等领域,深入研究反应器内气-液两相流体流动行为对提高其传质性能具有重要意义。通过分别建立气-液两相流模型和气泡粒群衡算模型并实现二者的耦合求解,研究了单个方形导流筒、单个圆形导流筒和6... 气升式环流反应器广泛应用于化工、环境等领域,深入研究反应器内气-液两相流体流动行为对提高其传质性能具有重要意义。通过分别建立气-液两相流模型和气泡粒群衡算模型并实现二者的耦合求解,研究了单个方形导流筒、单个圆形导流筒和6个圆形导流筒结构对气-液两相流体流动特性、气泡尺寸分布和气-液相间传质的影响。研究表明,含6个圆形导流筒结构的气升式环流反应器气含率和液相速度分布趋于均匀,平均气含率更大,气泡尺寸更小,传质速率更大,反应器的综合性能得到显著提升。相关模拟结果为气升式环流反应器结构优化和放大指明了方向。 展开更多
关键词 气升式环流反应器 计算流体力学 传质 数值模拟
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内循环气升式反应器的操作特性与流体力学研究
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作者 李亮 靳晓霞 +2 位作者 付春明 张成凯 郝润秋 《化学工业与工程》 CAS CSCD 北大核心 2024年第3期135-141,共7页
气升式反应器在化工和环境等领域有着广泛的应用,准确预测反应器内气液两相流动与传质行为对于反应器的设计与放大十分重要。论文通过建立稳态条件下内循环气升式反应器内的气液两相流动模型,实现对循环液速vL、气含率εG与气相循环比... 气升式反应器在化工和环境等领域有着广泛的应用,准确预测反应器内气液两相流动与传质行为对于反应器的设计与放大十分重要。论文通过建立稳态条件下内循环气升式反应器内的气液两相流动模型,实现对循环液速vL、气含率εG与气相循环比β等重要流体力学参数的求解。当提升管高度分别为2和6 m时,模型参数c0取0.65,模型计算的反应器内的vL与εG值与实验结果的相对平均误差小于6.2%。在此基础上,进一步考察了提升管高度H对平均循环液速和平均气含率的影响规律。模拟结果表明,随着提升管高度的增加,循环推动力增加,循环液速上升,平均气含率略有下降。下降管和提升管内气含率比α与反应器尺寸和表观气速等操作条件相关,取值范围为0.72~0.80。 展开更多
关键词 气升式反应器 稳态模拟 气相循环比 循环液速 气含率
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基于体系任务规划与仿真的运输机评估研究
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作者 王国陈 艾俊强 《计算机仿真》 2024年第5期24-28,404,共6页
战略运输机是一个国家战略能力的重要标志,而效费比评估研究是运输机论证的重要方面,是支撑装备发展或改进的重要依据。针对战略运输机的评估需求,从体系运用角度出发,基于任务规划与仿真推演,提出了一套效能评估指标体系与计算方法,并... 战略运输机是一个国家战略能力的重要标志,而效费比评估研究是运输机论证的重要方面,是支撑装备发展或改进的重要依据。针对战略运输机的评估需求,从体系运用角度出发,基于任务规划与仿真推演,提出了一套效能评估指标体系与计算方法,并通过建模形成了一套仿真环境。针对国内跨区投送以及海外投送想定,采用国外典型战略运输机,开展了装载规划与仿真推演,给出了各型运输机的效费比结果,为未来我国运输机的发展论证提供参考。 展开更多
关键词 战略运输机 效费比评估 任务规划 仿真推演
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气力提升系统气液两相流流动特性研究
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作者 朱井育 杜燕连 +3 位作者 符孟帝 韩雨彤 甘羽星 沈义俊 《力学与实践》 2024年第3期548-558,共11页
以空气-水作为介质,探究气举泵气液两相流的压力和流量特性,并基于压力信号的时域、功率谱密度函数(power spectral density,PSD)和概率密度函数(probability density function,PDF)分析鉴别流型。结果表明:除了进气喷嘴附近外,其他位... 以空气-水作为介质,探究气举泵气液两相流的压力和流量特性,并基于压力信号的时域、功率谱密度函数(power spectral density,PSD)和概率密度函数(probability density function,PDF)分析鉴别流型。结果表明:除了进气喷嘴附近外,其他位置的局部平均压力随气体流速的增大逐渐上升达到峰值后减小,峰值随着浸没比的减小而向右移动且上升速度增大;液体流速随着气体流速增大急剧上升达到峰值后几乎保持不变,最大提升效率约为49%,与最大液体流速并不发生在同一个气体流速下;在不同的气流量下,观测到气泡流、帽弹流、弹状流、搅拌流和环状流的出现,不同流型可通过PSD和PDF估计量进行识别;特别是,浸没比越小越有利于形成大气塞。目前,关于气举泵的研究非常有限,本研究结果可为气液固三相流和气液两相流的研究提供数据和技术支撑。 展开更多
关键词 气举泵 气液两相流 压力特性 流动特性 流型识别
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空气提升器运行特性及工程应用研究
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作者 祝永刚 谢寒 张驰 《价值工程》 2024年第6期143-145,共3页
空气提升器是目前放射性废液处理工程中应用较多的一种料液输送装置,可以有效解决放射性废液在常规方式下不便于输送的难题。本文简要介绍了空气提升器工作原理及运行特性,并基于现场设备调试时发现的问题,通过试验得出了该工程应用问... 空气提升器是目前放射性废液处理工程中应用较多的一种料液输送装置,可以有效解决放射性废液在常规方式下不便于输送的难题。本文简要介绍了空气提升器工作原理及运行特性,并基于现场设备调试时发现的问题,通过试验得出了该工程应用问题的处理方法及结论,旨在为处理放射性废液输送装置相关问题方面提供良好的工程借鉴,为后续工程设计提供经验反馈。 展开更多
关键词 空气提升器 调试 料液输送
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