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某复杂深井多区域作业通风系统的优化 被引量:12
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作者 程伯明 李义杰 +1 位作者 肖利民 姚炯 《矿业研究与开发》 CAS 北大核心 2019年第6期122-125,共4页
为解决某深井矿山井下作业区域风量分配不平衡、辅扇调控和管理难度大、溜井漏风等一系列通风问题,以矿山开采现状为基础,构建了6个主要通风单元。针对各通风单元存在的问题,经过对比分析,确定了1^#矿体8线以西通风单元采用-400m中段1^... 为解决某深井矿山井下作业区域风量分配不平衡、辅扇调控和管理难度大、溜井漏风等一系列通风问题,以矿山开采现状为基础,构建了6个主要通风单元。针对各通风单元存在的问题,经过对比分析,确定了1^#矿体8线以西通风单元采用-400m中段1^#回风井联络巷新增辅扇方案,马头山通风单元采用-510m中段回风井联络巷新增辅扇和-460m马头山斜坡道联络巷新增空气幕方案,并对其他主通风单元逐一进行了优化。利用Ventsim软件对优化后的矿井通风系统进行了网络解算,结果表明:优化后的矿井通风系统矿井总通风量、各单元通风量均可满足矿山实际生产通风需要。井下辅扇装机总台数由25台减少至18台,辅扇总装机功率由849kW降低至751kW,减少了井下辅扇总台数,降低了能耗。 展开更多
关键词 矿井通风 深井矿山 通风单元 通风优化
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区域单元+两翼对角混合式通风系统应用研究 被引量:12
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作者 盛建红 谭星宇 《矿业研究与开发》 CAS 北大核心 2018年第2期44-47,共4页
针对多中段同时开采、作业面多且分散、通风线路长等矿井通风问题,提出了以中段和工作面为服务对象的区域单元通风方式,建立了区域单元、两翼对角混合式通风系统,并通过Ventsim软件模拟分析了应用效果及合理性,分析结果表明,区域单元+... 针对多中段同时开采、作业面多且分散、通风线路长等矿井通风问题,提出了以中段和工作面为服务对象的区域单元通风方式,建立了区域单元、两翼对角混合式通风系统,并通过Ventsim软件模拟分析了应用效果及合理性,分析结果表明,区域单元+两翼对角混合式通风系统具有以中段和工作面为服务核心,有效风量率高,分风可控及风量调节灵活等诸多优点,值得推广应用的结论。 展开更多
关键词 矿井通风 区域单元 两翼对角式通风 VENTSIM 数值模拟
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大体量建筑的单元分区自然通风策略 被引量:12
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作者 陈晓扬 《建筑学报》 北大核心 2009年第11期58-61,共4页
针对大体量建筑的特点提出单元分区的自然通风策略,根据大体量建筑的不同类型,提出平面单元竖井式、大空间单元热压式、竖向单元组合式3种自然通风模式,并对每种模式进行了类型归纳。
关键词 自然通风 单元分区 大体量建筑 被动节能
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Effect of music therapy on short-term psychological and physiological outcomes in mechanically ventilated patients:A randomized clinical pilot study
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作者 Mark Ettenberger Rosangela Casanova-Libreros +7 位作者 Josefina Chávez-Chávez Jose Gabriel Cordoba-Silva William Betancourt-Zapata Rafael Maya Lizeth Alexa Fandino-Vergara Mario Valderrama Ingrid Silva-Fajardo Sandra Milena Hernández-Zambrano 《Journal of Intensive Medicine》 CSCD 2024年第4期515-525,共11页
Background:Elevated anxiety levels are common in patients on mechanical ventilation(MV)and may challenge recovery.Research suggests music-based interventions may reduce anxiety during MV.However,studies inves-tigating... Background:Elevated anxiety levels are common in patients on mechanical ventilation(MV)and may challenge recovery.Research suggests music-based interventions may reduce anxiety during MV.However,studies inves-tigating specific music therapy techniques,addressing psychological and physiological well-being in patients on MV,are scarce.Methods:This three-arm randomized clinical pilot study was conducted with MV patients admitted to the intensive care unit(ICU)of Hospital San Joséin Bogotá,Colombia between March 7,2022,and July 11,2022.Patients were divided into three groups:intervention group 1(IG1),music-assisted relaxation;intervention group 2(IG2),patient-preferred therapeutic music listening;and control group(CG),standard care.The main outcome measure was the 6-item State-Anxiety Inventory.Secondary outcomes were:pain(measured with a visual analog scale),resilience(measured with the Brief Resilience Scale),agitation/sedation(measured with the Richmond Agitation-Sedation Scale),vital signs(including heart rate,blood pressure,oxygen saturation,and respiratory rate),days of MV,extubation success,and days in the ICU.Additionally,three patients underwent electroencephalography during the interventions.Results:Data from 23 patients were analyzed in this study.The age range of the patients was 24.0-84.0 years,with a median age of 66.0 years(interquartile range:57.0-74.0).Of the 23 patients,19 were female(82.6%).No statistically significant differences between the groups were observed for anxiety(P=0.330),pain(P=0.624),resilience(P=0.916),agitation/sedation(P=0.273),length of ICU stay(P=0.785),or vital signs.A statistically significant difference between the groups was found for days of MV(P=0.019).Electroencephalography mea-surements showed a trend toward delta and theta band power decrease for two patients and a power increase on both beta frequencies(slow and fast)in the frontal areas of the brain for one patient.Conclusions:In this pilot study,music therapy did not significantly affect the anxiety levels in patien 展开更多
关键词 Music therapy Mechanical ventilation Intensive care unit ANXIETY PAIN
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Impact of non-alcoholic fatty liver disease on coronavirus disease 2019: A systematic review
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作者 Abdul Moeed Muhammad Omar Larik +5 位作者 Muhammad Ahmed Ali Fahim Hafsah Alim Ur Rahman Lubna Najmi Mah I Kan Changez Muhammad Moiz Javed Md Al Hasibuzzaman 《World Journal of Hepatology》 2024年第8期1185-1198,共14页
BACKGROUND Many studies have revealed a link between non-alcoholic fatty liver disease(NA-FLD)and coronavirus disease 2019(COVID-19),making understanding the relationship between these two conditions an absolute requi... BACKGROUND Many studies have revealed a link between non-alcoholic fatty liver disease(NA-FLD)and coronavirus disease 2019(COVID-19),making understanding the relationship between these two conditions an absolute requirement.AIM To provide a qualitative synthesis on the currently present data evaluating COVID-19 and NAFLD.METHODS This systematic review was conducted in accordance with the guidelines pro-vided by preferred reporting items for systematic reviews and meta-analyses and the questionnaire utilized the population,intervention,comparison,and outcome framework.The search strategy was run on three separate databases,PubMed/MEDLINE,Scopus,and Cochrane Central,which were systematically searched from inception until March 2024 to select all relevant studies.In addition,ClinicalTrials.gov,Medrxiv.org,and Google Scholar were searched to identify grey literature.RESULTS After retrieval of 11 studies,a total of 39282 patients data were pooled.Mortality was found in 11.5%and 9.4%of people in NAFLD and non-NAFLD groups.In all,23.2%of NAFLD patients and 22%of non-NAFLD admissions diagnosed with COVID-19 were admitted to the intensive care unit,with days of stay varying.Ventilatory support ranged from 5%to 40.5%in the NAFLD cohort and from 3.1%to 20%in the non-NAFLD cohort.The incidence of acute liver injury showed significance.Clinical improvement on days 7 and 14 between the two classifications was significant.Hospitalization stay ranged from 9.6 days to 18.8 days and 7.3 days to 16.4 days in the aforementioned cohorts respectively,with 73.3%and 76.3%of patients being discharged.Readmission rates varied.CONCLUSION Clinical outcomes except mortality consistently showed a worsening trend in patients with NAFLD and concomitant COVID-19.Further research in conducting prospective longitudinal studies is essential for a more powerful conclusion. 展开更多
关键词 Non-alcoholic fatty liver disease Coronavirus disease 2019 Mechanical ventilation Intensive care unit Acute liver injury
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多中段开采单元通风方式的研究与应用 被引量:3
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作者 谭星宇 杨倩 盛建红 《有色金属(矿山部分)》 2019年第2期90-94,共5页
多中段同时开采金属矿山普遍存在风量按需分配困难、有效风量率低和通风能耗高等问题。针对开采急倾斜极薄或薄矿体的金属矿山,运用单元通风原理,提出了一种多中段开采的单元通风方式。单元通风方式以用风部分为核心,将多个生产中段分... 多中段同时开采金属矿山普遍存在风量按需分配困难、有效风量率低和通风能耗高等问题。针对开采急倾斜极薄或薄矿体的金属矿山,运用单元通风原理,提出了一种多中段开采的单元通风方式。单元通风方式以用风部分为核心,将多个生产中段分成若干通风单元,各单元安装主扇,负责本单元的通风,通过单元主扇和中段内的调节设施调节各单元和生产中段的风量分配。将单元通风方式应用于河南某金矿通风系统优化改造,数值模拟分析表明,能解决目前矿山通风系统存在的主要问题,实现风量按需分配,也适用于其它类似金属矿山,具有一定的推广价值。 展开更多
关键词 通风系统 单元通风方式 多中段开采 优化改造 数值模拟
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Evaluation of progressive early rehabilitation training mode in intensive care unit patients with mechanical ventilation 被引量:3
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作者 Xiao-Jing Qie Zhi-Hong Liu Li-Min Guo 《World Journal of Clinical Cases》 SCIE 2022年第23期8152-8160,共9页
BACKGROUND Mechanical ventilation is a common resuscitation method in the intensive care unit(ICU).Unfortunately,this treatment process prolongs the ICU stay of patients with an increased incidence of delirium,which u... BACKGROUND Mechanical ventilation is a common resuscitation method in the intensive care unit(ICU).Unfortunately,this treatment process prolongs the ICU stay of patients with an increased incidence of delirium,which ultimately affects the prognosis.AIM To evaluate the effect of progressive early rehabilitation training on treatment and prognosis of patients with mechanical ventilation in ICU.METHODS The convenience sampling method selected 190 patients with mechanical ventilation admitted to the Fourth Hospital of Hebei Medical University from March 2020 to March 2021.According to the random number table method,they were divided into the control and intervention groups.The control group received routine nursing and rehabilitation measures,whereas the intervention group received progressive early rehabilitation training.In addition,the incidence and duration of delirium were compared for the two groups along with mechanical ventilation time,ICU hospitalization time,functional independence measure(FIM)score,Barthel index,and the incidence of complications(deep venous thrombosis,pressure sores,and acquired muscle weakness).RESULTS In the intervention group,the incidence of delirium was significantly lower than in the control group(28%vs 52%,P<0.001).In the intervention group,the duration of delirium,mechanical ventilation time,and ICU stay were shorter than in the control group(P<0.001).The FIM and Barthel index scores were significantly higher in the intervention group than the control group(P<0.001).The total incidence of complications in the intervention group was 3.15%,which was lower than 17.89%in the control group(P<0.001).CONCLUSION Progressive early rehabilitation training reduced the incidence of delirium and complications in ICU patients with mechanical ventilation,which improved prognosis and quality of life. 展开更多
关键词 Mechanical ventilation Intensive care unit Early rehabilitation training DELIRIUM Barthel index
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Intensivists’response to hyperoxemia in mechanical ventilation patients:The status quo and related factors 被引量:3
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作者 Zi-wei Ke Yue Jiang +5 位作者 Ya-ping Bao Ye-qin Yang Xiao-mei Zong Min Liu Xiang-yun Guan Zhong-qiu Lu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2021年第3期202-206,共5页
BACKGROUND:Due to the still sparse literature in China,the investigation of hyperoxemia management is required.Thus,we aim to conduct a retrospective study to provide more information about hyperoxemia management in i... BACKGROUND:Due to the still sparse literature in China,the investigation of hyperoxemia management is required.Thus,we aim to conduct a retrospective study to provide more information about hyperoxemia management in intensive care unit(ICU)patients.METHODS:We retrospectively screened the medical records of adult patients(age≥18 years)who required mechanical ventilation(MV)≥24 hours from January 1,2018,to December 31,2018.All arterial blood gas(ABG)tested during MV was retrieved,and MV settings were recorded.The median arterial partial pressure of oxygen(PaO2)>120 mmHg(1 mmHg=0.133 kPa)was defined as mild to moderate hyperoxemia,and PaO2>300 mmHg as extreme hyperoxemia.Intensivists’response to hyperoxemia was assessed based on the reduction of fraction of inspired oxygen(FiO2)within one hour after hyperoxemia was recorded.Multivariable logistic regression analysis was performed to determine the independent factors associated with the intensivists’response to hyperoxemia.RESULTS:A total of 592 patients were fi nally analyzed.The median Acute Physiology and Chronic Health Evaluation II(APACHE II)score was 21(15-26).The PaO2,arterial oxygen saturation(SaO2),FiO2,and positive end expiratory pressure(PEEP)were 96.4(74.0-126.0)mmHg,97.8%(95.2%-99.1%),0.4(0.4-0.5),and 5(3-6)cmH2O,respectively.Totally 174(29.39%)patients had PaO2>120 mmHg,and 19(3.21%)patients had extreme hyperoxemia at PaO2>300 mmHg.In cases of mild to moderate hyperoxemia with FiO2≤0.4,only 13(2.20%)patients had a decrease in FiO2 within one hour.The multivariable logistic regression analysis showed that a positive response was independently associated with FiO2(odds ratio[OR]1.09,95%confi dence interval[CI]1.06-1.12,P<0.001),PaO2(OR 1.01,95%CI 1.00-1.01,P=0.002),and working shifts(OR 5.09,95%CI 1.87-13.80,P=0.001).CONCLUSIONS:Hyperoxemia occurs frequently and is neglected in most cases,particularly when mild to moderate hyperoxemia,hyperoxemia with lower FiO2,hyperoxemia during night and middle-night shifts,or FiO2 less likely to be decreased 展开更多
关键词 Mechanical ventilation Hyperoxemia Fraction of inspired oxygen Arterial blood gas Intensive care unit
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基于PLC的矿井局部通风变频控制系统的设计 被引量:3
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作者 何波 《煤炭技术》 CAS 北大核心 2011年第10期48-49,共2页
将西门子PLC与ABB公司的ACS800系列变频器结合应用于矿井局部通风的的变频调速控制系统中,以矿井气压和瓦斯体积分数为控制参数,对通风机组工作状态进行有效控制,具有节能效果良好、运行稳定、智能化程度高的优点。
关键词 PLC 变频器 通风机组
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Effect of preoperative inspiratory muscle training on postoperative outcomes in patients undergoing cardiac surgery:A systematic review and meta-analysis 被引量:1
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作者 Jing Wang Yu-Qiang Wang +2 位作者 Jun Shi Peng-Ming Yu Ying-Qiang Guo 《World Journal of Clinical Cases》 SCIE 2023年第13期2981-2991,共11页
BACKGROUND Cardiovascular disease is the most prevalent disease worldwide and places a great burden on the health and economic welfare of patients.Cardiac surgery is an important way to treat cardiovascular disease,bu... BACKGROUND Cardiovascular disease is the most prevalent disease worldwide and places a great burden on the health and economic welfare of patients.Cardiac surgery is an important way to treat cardiovascular disease,but it can prolong mechanical ventilation time,intensive care unit(ICU)stay,and postoperative hospitalization for patients.Previous studies have demonstrated that preoperative inspiratory muscle training could decrease the incidence of postoperative pulmonary complications.AIM To explore the effect of preoperative inspiratory muscle training on mechanical ventilation time,length of ICU stay,and duration of postoperative hospitalization after cardiac surgery.METHODS A literature search of PubMed,Web of Science,Cochrane Library,EMBASE,China National Knowledge Infrastructure,WanFang,and the China Science and Technology journal VIP database was performed on April 13,2022.The data was independently extracted by two authors.The inclusion criteria were:(1)Randomized controlled trial;(2)Accessible as a full paper;(3)Patients who received cardiac surgery;(4)Preoperative inspiratory muscle training was implemented in these patients;(5)The study reported at least one of the following:Mechanical ventilation time,length of ICU stay,and/or duration of postoperative hospitalization;and(6)In English language.RESULTS We analyzed six randomized controlled trials with a total of 925 participants.The pooled mean difference of mechanical ventilation time was-0.45 h[95%confidence interval(CI):-1.59-0.69],which was not statistically significant between the intervention group and the control group.The pooled mean difference of length of ICU stay was 0.44 h(95%CI:-0.58-1.45).The pooled mean difference of postoperative hospitalization was-1.77 d in the intervention group vs the control group[95%CI:-2.41-(-1.12)].CONCLUSION Preoperative inspiratory muscle training may decrease the duration of postoperative hospitalization for patients undergoing cardiac surgery.More high-quality studies are needed to confirm our conclusion. 展开更多
关键词 Preoperative inspiratory muscle training Cardiac surgery Heart surgery Mechanical ventilation Intensive care unit Duration of postoperative hospitalization
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铜绿山矿通风系统方案优化 被引量:1
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作者 卢波 《现代矿业》 CAS 2017年第12期168-172,175,共6页
铜绿山矿深部工程建成投产后,深部开采的通风系统与原通风系统相互影响,造成通风系统短路,而且随着开采中段的下移,导致各中段工作面通风更加困难,通风管理难度增加。通过对铜绿山矿通风系统现场调查分析,得出矿井通风系统面临的主要问... 铜绿山矿深部工程建成投产后,深部开采的通风系统与原通风系统相互影响,造成通风系统短路,而且随着开采中段的下移,导致各中段工作面通风更加困难,通风管理难度增加。通过对铜绿山矿通风系统现场调查分析,得出矿井通风系统面临的主要问题,结合实际情况,拟定通风系统宏观构建方案并进行比选,选择单元通风方案,根据矿体分布使系统形成3个相对独立的通风单元并分别确定最优通风方案。实施结果显示,新的通风方案有效解决矿井通风系统短路和采区供风不足的问题,为国内同类型矿山通风系统改造提供借鉴。 展开更多
关键词 铜绿山矿 通风系统 通风单元 耦合优化
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Oxygenation strategies after extubation of critically ill and postoperative patients 被引量:1
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作者 Arnaud W.Thille Mathilde Wairy +1 位作者 Sylvain Le Pape Jean-Pierre Frat 《Journal of Intensive Medicine》 2021年第2期65-70,共6页
In intensive care units(ICUs),the decision to extubate is a critical one because mortality is particularly high in case of reintubation.Around 15%of patients ready to be weaned offa ventilator experience extubation fa... In intensive care units(ICUs),the decision to extubate is a critical one because mortality is particularly high in case of reintubation.Around 15%of patients ready to be weaned offa ventilator experience extubation failure leading to reintubation.The use of high-flow nasal oxygen and non-invasive ventilation are two alternatives of standard oxygen supplementation that may help to prevent reintubation.High-flow nasal oxygen and non-invasive ventilation,may be used to prevent reintubation in patients with low(e.g.,patients without comorbidities and with short durations of mechanical ventilation)and high risk(e.g.,patients>65 years and those with underlying cardiac disease,chronic respiratory disorders,and/or hypercapnia at the time of extubation)of reintubation,respectively.However,non-invasive ventilation used as a rescue therapy to treat established post-extubation respiratory failure could increase mortality by delaying reintubation,and should therefore be used very carefully in this setting.The oxygenation strategy to be applied in postoperative patients is different from the patients who are extubated in the ICUs.Standard oxygen after a surgical procedure is adequate,even following major abdominal or cardio-thoracic surgery,but should probably be switched to high-flow nasal oxygen in patients with hypoxemic.Unlike in patients experiencing post-extubation respiratory failure in ICUs wherein non-invasive ventilation may have deleterious effects,it may actually improve the outcomes in postoperative patients with respiratory failure.This review discusses the different clinical situations with the aim of choosing the most effective oxygenation strategy to prevent post-extubation respiratory failure and to avoid reintubation. 展开更多
关键词 Noninvasive ventilation High-flow nasal oxygen therapy ventilator weaning Airway extubation Mechanical ventilation Intensive care unit
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综合管廊通风系统设计分析 被引量:1
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作者 魏亚志 曹学明 丁路 《建筑热能通风空调》 2019年第3期76-78,共3页
结合现行综合管廊及相关设计规范,对综合管廊防火分区和通风单元划分,通风型式进行分析探讨,得到综合管廊常见舱室的通风单元长度,通风型式采用自然进风和机械排风相结合的方式。同时对管廊运行策略进行探讨,需要考虑夏季梅雨季节管廊... 结合现行综合管廊及相关设计规范,对综合管廊防火分区和通风单元划分,通风型式进行分析探讨,得到综合管廊常见舱室的通风单元长度,通风型式采用自然进风和机械排风相结合的方式。同时对管廊运行策略进行探讨,需要考虑夏季梅雨季节管廊结露情况,并提出解决措施,保证管廊长期有利运行。 展开更多
关键词 综合管廊 通风系统 通风单元及型式 运行策略
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地下汽车库供暖通风设计方案探讨 被引量:1
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作者 呼忠达 《暖通空调》 北大核心 2008年第8期88-89,共2页
结合具体工程,介绍了地下汽车库供暖、通风及防排烟系统的设计方案。
关键词 地下汽车库 防火分区 防烟分区 排风系统 排烟系统 诱导器
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直接膨胀式制冷机组在核电厂的应用
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作者 李广慧 胡北 《制冷与空调》 2023年第5期55-60,共6页
对直接膨胀式制冷机组在核电厂的应用技术进行研究。从系统、功能、结构、性能、载荷等方面介绍直接膨胀式制冷机组在核电厂通风系统中的设计特点;重点对核级直接膨胀式制冷机组的验证方法进行分析,包括样机选取、性能试验、老化试验、... 对直接膨胀式制冷机组在核电厂的应用技术进行研究。从系统、功能、结构、性能、载荷等方面介绍直接膨胀式制冷机组在核电厂通风系统中的设计特点;重点对核级直接膨胀式制冷机组的验证方法进行分析,包括样机选取、性能试验、老化试验、抗震验证、抗爆验证和软件验证。本研究可为核电厂直接膨胀式制冷机组的设计和验证提供依据,保障核电厂冷源的安全性和可靠性。 展开更多
关键词 核电厂 通风系统 制冷机组 直接膨胀 抗震 抗爆
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Acute exacerbation of interstitial lung disease in the intensive care unit 被引量:1
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作者 Antonios Charokopos Teng Moua +1 位作者 Jay H Ryu Nathan J Smischney 《World Journal of Critical Care Medicine》 2022年第1期22-32,共11页
Acute exacerbations of interstitial lung disease(AE-ILD)represent an acute,frequent and often highly morbid event in the disease course of ILD patients.Admission in the intensive care unit(ICU)is very common and the n... Acute exacerbations of interstitial lung disease(AE-ILD)represent an acute,frequent and often highly morbid event in the disease course of ILD patients.Admission in the intensive care unit(ICU)is very common and the need for mechanical ventilation arises early.While non-invasive ventilation has shown promise in staving off intubation in selected patients,it is unclear whether mechanical ventilation can alter the exacerbation course unless it is a bridge to lung transplantation.Risk stratification using clinical and radiographic findings,and early palliative care involvement,are important in ICU care.In this review,we discuss many of the pathophysiological aspects of AE-ILD and raise the hypothesis that ventilation strategies used in acute respiratory distress syndrome might be implemented in AE-ILD.We present possible decision-making and management algorithms that can be used by the intensivist when caring for these patients. 展开更多
关键词 Interstitial lung diseases Disease exacerbation Mechanical ventilation Intensive care unit Pathophysiological aspect
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Uniformity and energy evaluation of equal cross-section ventilation system(ECVS)for long tunnel in underground buildings
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作者 Qi Deng Huaican Liu +3 位作者 Yecong He Tengjin Huang Huan Zhou Ying Bao 《Energy and Built Environment》 2022年第1期86-94,共9页
Uniform ventilation is important for the safety of long tunnel in underground buildings,it is difficult to install the large size air duct to ensure the centerline of each cross-section of the traditional variable cro... Uniform ventilation is important for the safety of long tunnel in underground buildings,it is difficult to install the large size air duct to ensure the centerline of each cross-section of the traditional variable cross-section ventila-tion system(VCVS)superimposed on the same horizontal axis,which is significant to the ventilation uniformity,energy consumption and installation convenience of the VCVS.On the contrary,each cross-section of the Equal Cross-section Ventilation System(ECVS)has the same horizontal axis,therefore,it is more convenient to manu-facture and install the large size air duct in the underground long tunnel and achieve uniform ventilation.This study proposes an ECVS,using computational fluid dynamics(CFD)numerical simulation analyzed the influences of main duct velocity,aspect ratio,and outlet numbers on uniformity and energy consumption per unit air vol-ume(ECPV).It revealed that when each ventilation equalizer’s valve Angle𝛽is given,uniformity of air supply decreases slightly with an increase in the inlet velocity.When the air supply main duct aspect ratio increases,the outlet velocity standard deviation range is from 0.22 to 0.34.When outlet numbers N=7~12 and𝛽are constant,air supply uniformity and resistance coefficient𝜉also decrease with the decrease of outlet numbers.The outlet number has a significant influence on the uniformity of system air supply,main duct velocity,and aspect ratio are relatively small.ECPV is positively correlated with the main duct velocity and outlet number,and is negatively correlated with aspect ratio. 展开更多
关键词 ventilation equalizer Equal cross-section ventilation system(ECVS) Energy consumption per unit air volume(ECPV) Uniform air supply Resistance coefficient
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人防地下室通风排烟平战结合设计
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作者 刘坡军 《广东土木与建筑》 2009年第11期52-53,34,共3页
介绍人防地下室通风排烟的设计特点,结合工程实例阐述其合理性,同时强调了设计中需要注意的若干问题。
关键词 人防地下室 通风 防排烟 防护单元 防火分区
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沙曲瓦斯发电厂二期工程设计优化研究
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作者 闫中元 《煤炭工程》 北大核心 2022年第12期33-36,共4页
为了解决山西焦煤沙曲瓦斯发电厂二期工程存在的通风、冷却、爆震等问题,分析了现状厂房通风形式、冷却机组布置缺陷,从改善主厂房通风方式、优化冷却机组布置、提高冷却机组自身冷却能力等方面进行优化,使得厂房通风方式由原先的发动... 为了解决山西焦煤沙曲瓦斯发电厂二期工程存在的通风、冷却、爆震等问题,分析了现状厂房通风形式、冷却机组布置缺陷,从改善主厂房通风方式、优化冷却机组布置、提高冷却机组自身冷却能力等方面进行优化,使得厂房通风方式由原先的发动机侧自然进风屋顶强制排风变为两侧强制进风屋顶自然排风,主厂房夏季环境温度可保持在38℃以下,闭式冷却水箱能够获得新鲜冷空气进行冷却,缸套水冷却能力由836kW提升至1007kW。经改造后,厂房通风效果及机组冷却系统性能得到大幅提升,机组运行负荷率长期稳定在90%以上,爆震现象在一定程度上得到控制。 展开更多
关键词 瓦斯发电 厂房通风 冷却水箱布置 机组冷却
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Role of proning and positive end-expiratory pressure in COVID-19
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作者 Kejal D Gandhi Munish Sharma +1 位作者 Pahnwat Tonya Taweesedt Salim Surani 《World Journal of Critical Care Medicine》 2021年第5期183-193,共11页
The novel coronavirus,which was declared a pandemic by the World Health Organization in early 2020 has brought with itself major morbidity and mortality.It has increased hospital occupancy,heralded economic turmoil,an... The novel coronavirus,which was declared a pandemic by the World Health Organization in early 2020 has brought with itself major morbidity and mortality.It has increased hospital occupancy,heralded economic turmoil,and the rapid transmission and community spread have added to the burden of the virus.Most of the patients are admitted to the intensive care unit(ICU)for acute hypoxic respiratory failure often secondary to acute respiratory distress syndrome(ARDS).Based on the limited data available,there have been different opinions about the respiratory mechanics of the ARDS caused by coronavirus disease 2019(COVID-19).Our article provides an insight into COVID-19 pathophysiology and how it differs from typical ARDS.Based on these differences,our article explains the different approach to ventilation in COVID-19 ARDS compared to typical ARDS.We critically analyze the role of positive end-expiratory pressure(PEEP)and proning in the ICU patients.Through the limited data and clinical experience are available,we believe that early proning in COVID-19 patients improves oxygenation and optimal PEEP should be titrated based on individual lung compliance. 展开更多
关键词 COVID-19 Acute respiratory distress syndrome Positive end-expiratory pressure Proning ventilation management Acute respiratory distress syndrome Intensive care unit
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