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Analysis of the Efficacy of High-Flow Nasal Cannula Oxygen Therapy and Non-Invasive Ventilation in COPD Patients
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作者 Xue Yin Yan Li +6 位作者 Yan Ma Yue Sun Li Li Wenmei Yan Jianhua Zhang He Zhang Haisheng Yang 《Journal of Clinical and Nursing Research》 2025年第11期307-315,共9页
Patients with acute exacerbation of chronic obstructive pulmonary disease(COPD)often suffer from respiratory failure and require respiratory support therapy.High-flow nasal cannula oxygen therapy(HFNC)and non-invasive... Patients with acute exacerbation of chronic obstructive pulmonary disease(COPD)often suffer from respiratory failure and require respiratory support therapy.High-flow nasal cannula oxygen therapy(HFNC)and non-invasive positive pressure ventilation(NIPPV)are commonly used non-invasive respiratory support methods.HFNC can provide precisely heated and humidified high-flow oxygen,reducing dead space and increasing alveolar ventilation.NIPPV can supply stable high-concentration oxygen and improve gas exchange.This article reviews the application of HFNC and NIPPV in the acute exacerbation stage of COPD,aiming to provide references for reasonable clinical selection. 展开更多
关键词 Chronic obstructive pulmonary disease high-flow nasal cannula oxygen therapy Non-invasive ventilation Acute exacerbation stage
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High-flow nasal cannula oxygen therapy and noninvasive ventilation for preventing extubation failure during weaning from mechanical ventilation assessed by lung ultrasound score: A single-center randomized study 被引量:12
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作者 Shan-xiang Xu Chun-shuang Wu +1 位作者 Shao-yun Liu Xiao Lu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2021年第4期274-280,共7页
BACKGROUND: We sought to demonstrate the superiority of a targeted therapy strategy involving high-flow nasal cannula oxygen(HFNCO_(2)) therapy and noninvasive ventilation(NIV) using lung ultrasound score(LUS) in comp... BACKGROUND: We sought to demonstrate the superiority of a targeted therapy strategy involving high-flow nasal cannula oxygen(HFNCO_(2)) therapy and noninvasive ventilation(NIV) using lung ultrasound score(LUS) in comparison with standard care among patients in the intensive care unit(ICU) who undergo successful weaning to decrease the incidence of extubation failure at both 48 hours and seven days.METHODS: During the study period, 98 patients were enrolled in the study, including 49 in the control group and 49 in the treatment group. Patients in the control group and patients with an LUS score <14 points(at low risk of extubation failure) in the treatment group were extubated and received standard preventive care without NIV or HFNCO_(2). Patients with an LUS score ≥14 points(at high risk of extubation failure) in the treatment group were extubated with a second review of the therapeutic optimization to identify and address any persisting risk factors for postextubation respiratory distress;patients received HFNCO2 therapy combined with sessions of preventive NIV(4-8 hours per day for 4-8 sessions total) for the first 48 hours after extubation.RESULTS: In the control group, 13 patients had the LUS scores ≥14 points, while 36 patients had scores <14 points. In the treatment group, 16 patients had the LUS scores ≥14 points, while 33 patients had scores <14 points. Among patients with the LUS score ≥14 points, the extubation failure rate within 48 hours was 30.8% in the control group and 12.5% in the treatment group, constituting a statistically significant difference(P<0.05). Conversely, among patients with an LUS score <14 points, 13.9% in the control group and 9.1% in the treatment group experienced extubation failure(P=0.61). The length of ICU stay(9.4±3.1 days vs. 7.2±2.4 days) was significantly different and the re-intubation rate(at 48 hours: 18.4% vs. 10.2%;seven days: 22.4% vs. 12.2%) significantly varied between the two groups(P<0.05). There was no significant difference in the 28-day mortality rate(6.1% vs. 8.2%) between the control and treatment groups.CONCLUSIONS: Among high-risk adults being weaned from mechanical ventilation and assessed by LUS, the NIV+HFNCO_(2) protocol does not lessen the mortality rate but reduce the length of ICU stay, the rate of extubation failure at both 48 hours and seven days. 展开更多
关键词 high-flow nasal cannula oxygen Noninvasive ventilation Lung ultrasound EXTUBATION
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Statistical modelling for effect of mix-parameters on properties of high-flowing sand-concrete 被引量:7
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作者 T.BOUZIANI A.BENMOUNAH M.BDRINA 《Journal of Central South University》 SCIE EI CAS 2012年第10期2966-2975,共10页
The high-flowing sand-concrete (HFSC) containing natural sands as aggregate was carried out. The high fluidity and stability of HFSC can be achieved by tailoring the mix design parameters, such as fine to coarse san... The high-flowing sand-concrete (HFSC) containing natural sands as aggregate was carried out. The high fluidity and stability of HFSC can be achieved by tailoring the mix design parameters, such as fine to coarse sand ratio, dosage of additions, water to binder ratio and dosage of admixtures. Mini-cone slump test, v-fl.mnel time test and viscosity model parameters were used to characterize the behaviour of HFSC in fresh state. The mechanical compressive strength in 28 d was also determined. A factorial design approach was used to establish models highlighting the effect of each mix-parameter on measured properties of HFSC. The derived models are valid for mixtures made with 0 to 0.3 of dune sand to total sand ratio, 82 to 418 kg/m3 of marble powder, 0.42 to 0.46 of water/binder ratio and 1.3% to 1.9% of superplasticizer high water-reducer. The results show that the derived models constitute very efficient means for understanding the influence of key mix-parameters on HFSC properties and are useful in selecting the optimum mix proportions, by simulating their impact on fluidity, stability and compressive strength. 展开更多
关键词 high-flowing sand-concrete factorial design FLUIDITY VISCOSITY mix-design parameters
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Influence of fly ash on early-age cracking behavior of high-flowing concrete 被引量:5
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作者 郑建岚 王雪芳 《Journal of Central South University》 SCIE EI CAS 2009年第2期312-319,共8页
The effects of quality and content of fly ash on the early-age cracking behavior of high-flowing concrete (HFC) were investigated. The early-age cracking behavior of the HFC was analyzed by combining the tests of ev... The effects of quality and content of fly ash on the early-age cracking behavior of high-flowing concrete (HFC) were investigated. The early-age cracking behavior of the HFC was analyzed by combining the tests of evaporation capacity and electrical resistivity of the HFC. In these tests, a modified flat-type specimen was adopted. The results show that the HFC will have a lower evaporation capacity when it is mixed with fine fly ash, while it will have a higher evaporation capacity when grade II! fly ash is used as mineral admixture. And the electrical resistivity rate of HFC reduces with the increase of the content of fly ash. A nonlinear relationship exists between the cracking time of HFC and the minimum electrical resistivity. The early-age cracking behavior of HFC with fly ash can be enhanced by appropriately increasing the fine particle content and MgO, K2O, and SO3 contents of fly ash. The optimal content of fly ash, which makes a satisfied early-age cracking behavior of HFC, is obtained. And when the content of fly ash exceeds a critical value, the early-age cracking behavior of HFC will rapidly decrease. 展开更多
关键词 high-flowing concrete fly ash cracking behavior electrical resistivity
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Design and Experiment-Based Optimization of High-Flow Hydraulic One-Way Valves 被引量:4
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作者 Lei Liu Ping Yu 《Fluid Dynamics & Materials Processing》 EI 2020年第2期211-224,共14页
High-flow hydraulic one-way valves in water pipes are typically used to mitigate conditions,which would otherwise cause vibration and cavitation erosion after long-term operation.To prevent cavitation and enhance the ... High-flow hydraulic one-way valves in water pipes are typically used to mitigate conditions,which would otherwise cause vibration and cavitation erosion after long-term operation.To prevent cavitation and enhance the performance of hydraulic one-way valves,in the present work a dedicated experimental study has been conducted.The structural parameters relating to the pilot valve core,the main valve core,and the through-flow section of the considered flow channel have been changed to analyse reverse impact,and cavitation,characteristics.The results show that the control pressure has a weak effect on the cavitation characteristics,while changes in the structural parameters can significantly affect them.In particular,the cavitation index,representing the extent of cavitation,has been found to display a linear correlation with the inlet pressure,but,not with the inlet flow rate.Most importantly,a stepped throttling structure can reduce the pressure oscillation,improve the response speed,enhance the impact characteristics,and decrease the likelihood and severity of cavitation.The larger the flow passage area,the shorter the unloading time.Cavitation mainly occurs when the pilot valve core is fully opened.The stepped main valve core throttling structure has been found to be an optimal option. 展开更多
关键词 high-flow structural design IMPACT CAVITATION
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Dynamic characteristics of the high-flow water three-way valve 被引量:2
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作者 Chuan-Li WANG Xia GAO Hai-Shun DENG Yu HUANG 《Journal of Coal Science & Engineering(China)》 2013年第3期392-395,共4页
Operating principle of water three-way valve with high flow for individual hydraulic prop in coal was presented in this paper, its strict and precise mathematical model was established, its flow field was simulated nu... Operating principle of water three-way valve with high flow for individual hydraulic prop in coal was presented in this paper, its strict and precise mathematical model was established, its flow field was simulated numerically by software Fluent, and its dynamic characteristics were analyzed during the work process such as raising leg, loading and overflow, the influence of the related parameters on high-flow water three-way valve was determined. The results as follows: during the raising leg stage and early raising leg stage, when the damping ratio increases, the overshoot of system decreases and the setting time reduces, and the dynamic response performance has a significant improvement. During the loading stage and the overflow stage, the pressure in plunger chamber of single hydraulic prop, the output flow and the displacement of the high-flow water three-way valve decrease with the decreasing of the external load. The spring stiffness of the safety valve directs the flow and the spool's displacement of the safety valve, and it can be used to control the high-flow three-way valve's sensitivity. 展开更多
关键词 high-flow three-way valve water hydraulic structural design dynamic characteristics
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Sleep Quality for Patients Receiving Noninvasive Positive Pressure Ventilation and Nasal High-Flow Oxygen Therapy in an ICU: Two Case Studies 被引量:1
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作者 Hiroaki Murata Yoko Yamaguchi 《Open Journal of Nursing》 2018年第9期605-615,共11页
Aim: The purpose of this case study was to examine the sleep quality of patients receiving noninvasive positive pressure ventilation (NPPV) or nasal high-flow oxygen therapy (NHF) in an intensive care unit and to inve... Aim: The purpose of this case study was to examine the sleep quality of patients receiving noninvasive positive pressure ventilation (NPPV) or nasal high-flow oxygen therapy (NHF) in an intensive care unit and to investigate what types of nursing support are offered to such patients. Methods: We examined one patient each for NPPV and NHF. Polysomnography (PSG), review of the patient charts, and semi-structured interviews were used to collect the data for analysis. Results: Patients treated with NPPV or NHF demonstrated a noticeable reduction in deep sleep, with most of their sleep being shallow. Their sleep patterns varied greatly from those of healthy individuals. These results suggest that, in addition to experiencing extremely fragmented sleep, sleep in these patients was more likely to be interrupted by nursing interventions, such as during auscultation of breath sounds. Furthermore, it was revealed that “anxiety or discomfort that accompanies the mask or air pressure” in patients treated with NPPV and “discomfort that accompanies the nasal cannula or NHF circuit” in patients treated with NHF may be primary causes of disrupted sleep. Our results suggest a need for nursing care aimed at improving sleep quality in patients treated with NPPV or NHF. 展开更多
关键词 Noninvasive Positive Pressure Ventilation (NPPV) NASAL high-flow Oxygen Therapy (NHF) Sleep DEPRIVATION ICU Post Intensive Care Syndrome (PICS)
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Efficacy of high-flow nasal cannula on acute exacerbation of chronic obstructive pulmonary disease: A meta-analysis 被引量:1
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作者 Ying-Ming Sun Min Zhang +2 位作者 Na Sun Zhi Guan Ying Wang 《Medical Data Mining》 2019年第4期142-149,共8页
Objective:To systematically evaluate the efficacy and feasibility of high-flow nasal cannula(HFNC)on patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods:Systematic searches on Pub... Objective:To systematically evaluate the efficacy and feasibility of high-flow nasal cannula(HFNC)on patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods:Systematic searches on PubMed,Web of Science,the Cochrane Library,Embase,CBM(Chinese Biomedicine Database),CNKI(China National Knowledge Infrastructure),Wanfang Database and VIP were performed for randomized controlled trials(RCTs)which explored the effects of HFNC on patients with AECOPD.The retrieval time was from the establishment of each database to July 2019.RevMan5.3 software was used for statistical analysis.Results:A total of 12 articles were included,involving 812 patients.The results showed that:(1)Compared with conventional oxygen therapy,HFNC could improve patients'arterial partial oxygen pressure(PaO2)(MD=12.70,95%CI(7.00,18.40),Z=4.37,P<0.0001),reduce partial arterial blood carbon dioxide(PaCO2)(MD=-10.99,95%CI(-14.42,-7.55),Z=6.26,P<0.00001)and reduce endotracheal intubation rate(OR=0.19,95%CI(0.04,0.93),Z=2.05,P=0.04),shorten the hospitalization time(SMD=-0.74,95%CI(-1.11,-0.37),Z=3.95,P<0.0001).(2)Compared with non-invasive positive pressure ventilation,it has fewer adverse reactions(OR=0.18,95%CI(0.09,0.35),Z=5.08,P<0.00001)and shorter hospital stay(SMD=-0.57,95%CI(-0.90,-0.23),Z=3.33,P=0.0009).Conclusion:HFNC can improve the patients’hypoxia symptoms and CO2 retention,reduce the rate of tracheal intubation,and alleviate adverse reactions.However,Limited by the quality and region of the included studies,more high-quality are needed to test it. 展开更多
关键词 high-flow nasal cannula AECOPD Non-invasive positive pressure ventilation Conventional oxygen therapy META-ANALYSIS
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Prone position combined with high-flow nasal oxygen could benefit spontaneously breathing, severe COVID-19 patients:A case report
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作者 Da-Wei Xu Guang-Liang Li +1 位作者 Jiong-Han Zhang Fei He 《World Journal of Clinical Cases》 SCIE 2021年第17期4381-4387,共7页
BACKGROUND Since the outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China in December 2019,the overall fatality rate of severe and critical patients with COVID-19 is high and the effective therapy is limited.C... BACKGROUND Since the outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China in December 2019,the overall fatality rate of severe and critical patients with COVID-19 is high and the effective therapy is limited.CASE SUMMARY In this case report,we describe a case of the successful combination of the prone position(PP)and high-flow nasal oxygen(HFNO)therapy in a spontaneously breathing,severe COVID-19 patient who presented with fever,fatigue and hypoxemia and was diagnosed by positive throat swab COVID-19 RNA testing.The therapy significantly improved the patient's clinical symptoms,oxygenation status,and radiological characteristics of lung injury during hospitalization,and the patient showed good tolerance and avoided intubation.Additionally,we did not find that medical staff wearing optimal airborne personal protective equipment(PPE)were infected by the new coronavirus in our institution.CONCLUSION We conclude that the combination of PP and HFNO could benefit spontaneously breathing,severe COVID-19 patients.The therapy does not increase risk of healthcare workers wearing optimal airborne PPE to become infected with virus particles. 展开更多
关键词 COVID-19 HYPOXEMIA high-flow nasal oxygen Intubation and prone position Case report
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Efficacy and Safety of Treatment of High-flow Priapism with Superselective Transcatheter Embolization
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作者 Tao QI Lei YE +5 位作者 Zheng CHEN Zhan-sen HUANG Bo WANG Hao LI Bin ZHANG Jun CHEN 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2018年第1期101-106,共6页
This study is aimed to evaluate the effectiveness and safety of the treatment of highflow priapism with superselective transcatheter embolization.From Sep.1999 to Jan.2013,six patients with high-flow priapism underwen... This study is aimed to evaluate the effectiveness and safety of the treatment of highflow priapism with superselective transcatheter embolization.From Sep.1999 to Jan.2013,six patients with high-flow priapism underwent superselective transcatheter embolization of the cavernous artery.Recurrence of priapism,and change in erectile function detected by nocturnal penile tumescence and rigidity(NPTR)test and the International Index of Erectile Function 5-item questionnaire(IIEF-5)were evaluated during a mean follow-up of 12 months.A single superselective transcatheter embolization was sufficient for complete resolution of priapism in the six patients.None of the patients had a relapse of priapism after embolization,and all the patients who had premorbid normal erectile function showed maintained potency with normal results of NPTR and a mean postoperative IIEF-5 score of 23.5(range 23 to 24)during the follow-up period.In conclusion,superselective transcatheter embolization is an effective and safe treatment method for high-flow priapism,and it can ensure a high level of preservation of premorbid erectile function. 展开更多
关键词 high-flow priapism superselective transcatheter embolization
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Analysis of the Efficacy of Humidified High-Flow Nasal Oxygen Therapy Combined with Alveolar Lavage in the Treatment of Patients with Severe Pneumonia Complicated with Respiratory Failure
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作者 Lianyu Zhang 《Journal of Clinical and Nursing Research》 2023年第3期112-117,共6页
Objective:To analyze the curative effect of humidified high-flow nasal oxygen therapy combined with alveolar lavage in patients with severe pneumonia and respiratory failure.Methods:120 patients with severe pneumonia ... Objective:To analyze the curative effect of humidified high-flow nasal oxygen therapy combined with alveolar lavage in patients with severe pneumonia and respiratory failure.Methods:120 patients with severe pneumonia complicated with respiratory failure admitted to the Third People’s Hospital of Xining from July 2021 to December 2022 were randomly divided into two groups:group A and group B.The patients in group A were given humidified high-flow nasal oxygen therapy combined with alveolar lavage,whereas those in group B were given humidified high-flow nasal oxygen therapy.The treatment efficacy,blood gas analysis results,and differences in inflammatory mediators were compared between the two groups.Results:The curative effect in group A(96.67%)was significantly higher than that in group B(81.67%),P<0.05;the partial pressure of carbon dioxide(PaCO2),partial pressure of oxygen(PaO2),oxygen saturation(SpO2),and Horowitz index(P/F)of group A were significantly better than group B,P<0.05;the interleukin 6(IL-6),tumor necrosis factor alpha(TNF-α),and C-reactive protein(CRP)levels,white blood cell(WBC)count,serum procalcitonin(PCT),and neutrophil(N)percentage of group A were significantly lower than those of group B,P<0.05.Conclusion:For patients with severe pneumonia complicated with respiratory failure,alveolar lavage,on the basis of humidified high-flow oxygen therapy,can inhibit local inflammation,improve blood gas analysis results,promote disease recovery,and improve the clinical treatment effect。 展开更多
关键词 Alveolar lavage high-flow oxygen therapy Humidified nasal oxygen therapy Severe pneumonia Respiratory failure
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Impact and Management under Extracorporeal Circulation of a Patient with Renal Insufficiency on Dialysis with a High-Flow Arteriovenous Fistula in the Cardiac Surgery Department of the Angers Teaching Hospital about a Case and Review of the Literature
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作者 Abdoulaye Kanté Bréhima Coulibaly +6 位作者 Mamadou Diakité Mamadou A. Keita Bakary Keita Drissa Traoré Nouhoum Ongoïba Patrice Binuani Christophe Baufreton 《Open Journal of Thoracic Surgery》 2023年第1期1-5,共5页
Arteriovenous fistulas have a substantial impact on systemic hemodynamics, however their effect on extracorporeal circulation is not well understood. We report our clinical observation on the management under extracor... Arteriovenous fistulas have a substantial impact on systemic hemodynamics, however their effect on extracorporeal circulation is not well understood. We report our clinical observation on the management under extracorporeal circulation of a patient with renal insufficiency with a high-flow arteriovenous fistula. This is a 59-year-old man who was referred to us for surgical treatment of ischemic coronary artery disease in a context of anuric chronic renal failure. Hypothermia at 32°C is started from the start in CEC due to hyperflow at the level of the arteriovenous fistula. We performed two coronary artery bypasses of the marginal and IVA via the two internal thoracic arteries. The patient is hemofiltered in order to avoid hyperkalaemia and possibly avoid fluid overload related to filling per CEC. The clamping time was 71 minutes and the SCC lasted 141 minutes. There was no homologous transfusion in the operating room. It turns out that the input/output balance is zero at the end of the CEC. The postoperative course was simple. 展开更多
关键词 Coronaryartery by Pass Grafting High Flow Arteriovenous Fistula Extracorporeal Circulation HYPOTHERMIA
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深空探测器进入行星大气面临的极高速流动与传热基础科学问题
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作者 唐志共 张志刚 +4 位作者 粟斯尧 杨强 胡华雨 党雷宁 罗仕超 《空气动力学学报》 北大核心 2026年第1期1-5,共5页
火星采样、载人登月、木星系探测等深空探测任务中,探测器将以超行星第一宇宙速度进入地外行星大气或返回地球大气,系统能量大幅增加,出现伴随超高温物理化学反应的极高速流动与传热现象,其中涉及微观物理化学反应与宏观流动、流固界面... 火星采样、载人登月、木星系探测等深空探测任务中,探测器将以超行星第一宇宙速度进入地外行星大气或返回地球大气,系统能量大幅增加,出现伴随超高温物理化学反应的极高速流动与传热现象,其中涉及微观物理化学反应与宏观流动、流固界面传热传质,以及防热材料内部热力响应等不同时空尺度过程的复杂相互作用。如何准确描述预示这样一个多相态、多尺度、多过程强耦合的极端流动与传热系统,从而支撑探测器精细化设计,以实现动能高效耗散与热量有效隔绝,对流体力学及相关学科提出了严峻挑战。本文聚焦深空探测器进入行星大气过程中的极高速流动与传热问题,探讨梳理了极高速流动、强辐射传热、超高温物理化学反应3个方面的基础科学问题,并对我国未来该领域研究进行了展望。 展开更多
关键词 深空探测器 极高速流动 强辐射传热 超高温理化反应
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转臂式高速离心机减阻设计及机室流场特性研究
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作者 陈红永 杨鑫 +4 位作者 黎启胜 龚志斌 宋琼 李心耀 尹益辉 《应用力学学报》 北大核心 2026年第1期164-170,共7页
风阻功率是大型转臂式土工离心机驱动功率设计的重要依据,机室流场具有随流、温升、流速高等特点。为降低风阻需对转臂或吊篮采取整流减阻设计。针对两型分别采用转臂整流和整流罩减阻的离心机,开展了基于CFD(computational fluid dynam... 风阻功率是大型转臂式土工离心机驱动功率设计的重要依据,机室流场具有随流、温升、流速高等特点。为降低风阻需对转臂或吊篮采取整流减阻设计。针对两型分别采用转臂整流和整流罩减阻的离心机,开展了基于CFD(computational fluid dynamics)的气动特性仿真,通过优化仿真参数获得离心机高速运行时的机室内部流场流场特性及离心机风阻功率,并通过型线设计对离心机整流罩进行了气动阻力系数优化。研究表明:高速离心机低气压运行时机室下壁面的摩擦阻力矩占主导,高于周向壁面的摩擦阻力矩;吊篮不采用整流罩时,在迎风端面肩部出现了流动分离,压差阻力较大;采用整流罩后,吊篮前缘肩部的分离被削弱,总阻力系数大幅降低。研究表明对于高速离心机开展整流设计是必要的,通过转臂外形设计及整流罩设计,可有效降低风阻功率,更有益于控制机室温升。 展开更多
关键词 转臂式离心机 高速转动 流场 CFD 整流罩
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涡流发生器对动车组气动减阻的研究
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作者 崔洪江 吴博威 +1 位作者 樊伟航 关颖 《铁道学报》 北大核心 2026年第2期31-39,共9页
为了降低列车高速运行受到的气动阻力,选择尾车3个典型安装位置,包括流线型过渡位置、边界层突变处和尾车压力突变处。采用基于SST k-ω湍流模型的雷诺时均法研究高速列车尾车安装涡流发生器对尾部流动特征以及列车气动载荷的影响。结... 为了降低列车高速运行受到的气动阻力,选择尾车3个典型安装位置,包括流线型过渡位置、边界层突变处和尾车压力突变处。采用基于SST k-ω湍流模型的雷诺时均法研究高速列车尾车安装涡流发生器对尾部流动特征以及列车气动载荷的影响。结果表明:涡流发生器能显著改变尾车周围的流场,产生一对与原涡流旋向相反的涡流结构,降低尾流涡强度和范围。在尾车安装涡流发生器后,气流流动受到涡流发生器的阻碍产生积聚,从而在尾车表面形成正压区域,降低压差阻力;当涡流发生器布置在尾车压力突变处时,阻力显著降低,尾车阻力降低16.8%,整车阻力降低6.82%。研究结果为动车组气动减阻提供了新的思路,对突破传统气动减阻技术的局限性具有重要意义。 展开更多
关键词 动车组 流动控制 涡流发生器 气动减阻 压差阻力
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纳米气泡驱油技术的动态封堵机理与渗透率适配性研究
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作者 于春磊 孙强 +3 位作者 张翼飞 张瑞超 王硕亮 黄迎松 《油气地质与采收率》 北大核心 2026年第1期117-125,共9页
常规水驱是油田开发的基础技术,但在高含水后期,储层非均质性易诱发产生优势渗流通道,导致注入水低效循环,制约了采收率的进一步提升。为突破此技术瓶颈,开展了基于纳米气泡动态封堵机理的渗流调控研究。岩心单相渗流实验表明,纳米气泡... 常规水驱是油田开发的基础技术,但在高含水后期,储层非均质性易诱发产生优势渗流通道,导致注入水低效循环,制约了采收率的进一步提升。为突破此技术瓶颈,开展了基于纳米气泡动态封堵机理的渗流调控研究。岩心单相渗流实验表明,纳米气泡水在渗透率为10.12×10^(-3)~100.30×10^(-3)μm^(2)的储层中表现出显著的封堵能力,其阻力系数为1.33~1.51,残余阻力系数为1.18~1.38。大尺寸微观可视化驱替实验进一步直观揭示其提高采收率机理:纳米气泡通过选择性封堵高渗透通道,有效引导液流转向未动用区域,使波及体积扩大28.6%,采收率提高20百分点。基于此,提出了三区段孔喉适配认识,明确了气泡-孔喉直径比为0.1~0.3是封堵效率的有效区间。胜利油田W39井组的矿场试验验证了该技术的工程有效性,在连续注入10^(8)00 m^(3)纳米气泡水(平均直径为550 nm,浓度>4.0×10^(8)个/mL,制备成本为0.5元/m^(3))后,注入井压力上升2.4 MPa,主流线生产井的日产油量提升17.6%,含水率下降4.1百分点。 展开更多
关键词 纳米气泡 动态封堵 孔喉匹配 液流转向 高含水油藏
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综合营养支持策略对慢性阻塞性肺疾病急性加重患者氧疗效果的影响
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作者 程清 许杰超 +2 位作者 吴雁 渠慎强 刘晓慧 《医学工程与医用气体》 2026年第1期35-38,共4页
目的探讨综合营养支持策略对经鼻高流量氧疗(HFNC)的慢性阻塞性肺疾病急性加重(AECOPD)患者临床预后的影响。方法选择2023年5月至2025年4月江苏省中西医结合医院收治的96例AECOPD患者,使用SPSS 23.0软件生成随机数字将患者分为试验组和... 目的探讨综合营养支持策略对经鼻高流量氧疗(HFNC)的慢性阻塞性肺疾病急性加重(AECOPD)患者临床预后的影响。方法选择2023年5月至2025年4月江苏省中西医结合医院收治的96例AECOPD患者,使用SPSS 23.0软件生成随机数字将患者分为试验组和对照组。两组均给予HFNC,对照组给予常规肠内营养,试验组给予肠内与肠外相结合的综合营养支持策略。对比两组血清白蛋白(ALB)、血红蛋白(Hb)、转铁蛋白(TF)、动脉血氧分压(PaO_(2))、动脉血二氧化碳分压(PaCO_(2))、白介素10(IL-10)、超敏C反应蛋白(hs-CRP)、肿瘤坏死因子α(TNF-α)水平以及临床预后不良率。结果治疗7 d后,试验组Hb、ALB、TF、PaO_(2)水平均高于对照组(P<0.05),PaCO_(2)、IL-10、hs-CRP、TNF-α水平均低于对照组(P<0.05);随访3个月,试验组临床预后不良率低于对照组(P<0.05)。结论相比于单纯肠内营养,综合营养支持策略能进一步改善AECOPD患者营养状态,增强HFNC治疗效果,减轻炎症反应,改善临床预后。 展开更多
关键词 综合营养支持策略 经鼻高流量氧疗 慢性阻塞性肺疾病 临床预后
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高水位卵石层盆式注浆止水技术研究及工程应用
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作者 寇鼎涛 王炳禄 +2 位作者 陈贤波 刘志伟 华针 《现代隧道技术》 北大核心 2026年第1期239-247,270,共10页
为解决高水位、动水条件下卵石地层注浆止水效果不佳的问题,通过室内动水止水试验,分析不同注浆材料在高水头、动水条件下卵石层中的适用性。结果表明,水性聚氨酯在高水头、动水条件下止水能力强,留存率高;水泥-水玻璃双液浆和快硬硫铝... 为解决高水位、动水条件下卵石地层注浆止水效果不佳的问题,通过室内动水止水试验,分析不同注浆材料在高水头、动水条件下卵石层中的适用性。结果表明,水性聚氨酯在高水头、动水条件下止水能力强,留存率高;水泥-水玻璃双液浆和快硬硫铝酸盐水泥浆液在同等工况下止水效果不明显、留存率低。在此基础上,依托北京地铁某车站换乘厅基坑工程,通过设置试验区域,对浆液材料的实际应用效果、不同施工工艺的适用性及注浆施工参数进行验证,并依据试验结果对后续整体注浆施工方案进行修正。工程实施时,通过控域注浆对开挖区域进行分区,可进一步降低开挖施工风险,保障基坑开挖作业顺利完成。 展开更多
关键词 高水头 动水 富水砂卵石地层 注浆加固 水性聚氨酯 围蔽式止水帷幕
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基于可视化模型的缝洞型油藏高含沥青质稠油流动及水驱特征
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作者 刘磊 李晶辉 +4 位作者 刘玉国 曹畅 闫永赞 丁红雨 徐龙 《辽宁石油化工大学学报》 2026年第1期37-44,共8页
缝洞型油藏非均质性强、流体流态复杂,高含沥青质稠油流动特征及水驱规律不明确,给油田注水开发造成极大的困难。基于可视化缝洞模型,开展不同黏度稠油流动及水驱效果实验,建立了含沥青质稠油流动阻力系数与黏度及流量的关系;结合图像... 缝洞型油藏非均质性强、流体流态复杂,高含沥青质稠油流动特征及水驱规律不明确,给油田注水开发造成极大的困难。基于可视化缝洞模型,开展不同黏度稠油流动及水驱效果实验,建立了含沥青质稠油流动阻力系数与黏度及流量的关系;结合图像识别实现不同孔洞含油饱和度动态量化,明确了高含沥青质稠油在缝洞中的水驱特征及稠油黏度、裂缝参数和注水速度对驱油效果的影响。结果表明,当稠油黏度从59 mPa·s(中黏)增加到1090 mPa·s(特黏)时,缝洞中稠油拟启动压力梯度增大了1个数量级,流动阻力系数增加了3倍;水驱采收率降低了9.6个百分点;当稠油黏度增大时,水驱波及孔洞数量减少,剩余阁楼油、局部高部位油和壁面油增加;裂缝宽度、长度及空间位置分布对水驱稠油液流走向的影响较大,且该作用强于油水重力分异作用;注水初期适当增大注水速度,水驱在小尺度裂缝宽度中的波及、突破能力增加。 展开更多
关键词 缝洞储层 高含沥青质稠油 流动规律 水驱特征 可视化 稠油黏度
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经鼻高流量氧疗对高海拔地区胸腔镜手术患者术后恢复质量的影响
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作者 次德吉 赵佳乐 +1 位作者 权翔 黄宇光 《临床麻醉学杂志》 北大核心 2026年第2期113-116,共4页
目的探讨经鼻高流量氧疗(HFNC)对高海拔地区胸腔镜手术患者术后恢复质量的影响。方法选择择期行全麻下胸腔镜手术的患者,年龄18~74岁,ASAⅠ—Ⅲ级。将患者随机分为两组:HFNC组(H组)和常规鼻导管组(S组)。在PACU内,H组接受HFNC治疗,40 L/... 目的探讨经鼻高流量氧疗(HFNC)对高海拔地区胸腔镜手术患者术后恢复质量的影响。方法选择择期行全麻下胸腔镜手术的患者,年龄18~74岁,ASAⅠ—Ⅲ级。将患者随机分为两组:HFNC组(H组)和常规鼻导管组(S组)。在PACU内,H组接受HFNC治疗,40 L/min,FiO_(2)45%。S组给予鼻导管吸湿化纯氧6 L/min。两组均在转回病房后继续接受相应的氧疗至术后24 h。主要指标为PACU氧疗期间低氧血症的发生率。次要指标包括PACU留观时间、PACU氧疗期间SpO_(2)及最低SpO_(2)、病房期间SpO_(2)、术后住院时间。不良反应包括术后肺不张、肺部感染、静脉血栓、再次插管事件。结果共纳入患者79例,S组40例,H组39例。与S组比较,H组PACU氧疗期间及病房期间低氧血症发生率明显降低,氧疗期间SpO_(2)及最低SpO_(2)、病房期间SpO_(2)明显升高,术后肺不张和静脉血栓事件发生率明显降低,PACU留观时间和术后住院时间明显缩短(P<0.05)。两组再次插管率和肺部感染等术后并发症发生率差异无统计学意义。结论在高海拔地区接受胸腔镜手术患者中,HFNC可显著降低术后低氧血症,改善氧合情况,降低肺不张等术后并发症的发生率,并缩短PACU留观时间和术后住院时间。 展开更多
关键词 经鼻高流量氧疗 高海拔地区 术后恢复质量 麻醉恢复室 胸腔镜手术
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