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Adherence to Physical Measures during the SARS-COV2 Pandemic by Haemodialysis Patients in a Burkina Faso Tertiary Hospital: A Cross-Sectional Survey
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作者 Bonzi Y. Juste Zoehinga Patrice +4 位作者 Sourabie Oumar Kabore D. Dieudonne Hien Siebou Sawadogo Amidou Coulibaly Gerard 《Open Journal of Nephrology》 2024年第3期375-385,共11页
Context: COVID-19 can spread rapidly in haemodialysis centres, leading to fatal outcomes. Implementing physical measures is crucial in limiting the spread of infection. Aims: To assess adherence to physical measures a... Context: COVID-19 can spread rapidly in haemodialysis centres, leading to fatal outcomes. Implementing physical measures is crucial in limiting the spread of infection. Aims: To assess adherence to physical measures against SARS-Cov2 in haemodialysis patients. Methods and Material: From 13 to 19 July 2021, we administered the questionnaire to haemodialysis patients during or immediately after the dialysis session. The dependent variables were adherence to wearing masks, hand washing outside the dialysis centre, social distancing of at least 1.5 meters, and cough and sneeze hygiene. Statistical Analysis Used: Data were analyzed using Epi info software;descriptive statistics were presented as mean, headcount, and percentage;related factors were determined by multi-logistic regression. The significance level was 5%. The Health Research Ethics Committee approved the research protocol. Results: 142 patients were included (mean age: 42.5 ± 14 years). Wearing masks, hand-washing, social distancing, and coughing and sneezing hygiene were observed by 88%, 75%, 47%, and 60% of patients, respectively. Conclusion: Wearing masks was the most respected physical measure, while social distancing was the least respected. 展开更多
关键词 Physical measures COVID-19 HAEMODIALYSIS SARS-COV2 Tertiary Hospital Sub-Saharan Africa
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On Boolean elements and derivations in 2-dimension linguistic lattice implication algebras
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作者 ZHU Hua ZHAO Jian-bin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第2期274-292,共19页
A 2-dimension linguistic lattice implication algebra(2DL-LIA)can build a bridge between logical algebra and 2-dimension fuzzy linguistic information.In this paper,the notion of a Boolean element is proposed in a 2DL-L... A 2-dimension linguistic lattice implication algebra(2DL-LIA)can build a bridge between logical algebra and 2-dimension fuzzy linguistic information.In this paper,the notion of a Boolean element is proposed in a 2DL-LIA and some properties of Boolean elements are discussed.Then derivations on 2DL-LIAs are introduced and the related properties of derivations are investigated.Moreover,it proves that the derivations on 2DL-LIAs can be constructed by Boolean elements. 展开更多
关键词 DERIVATION Boolean element Lattice implication algebra(LIA) 2-dimension linguistic lattice implication algebra(2DL-LIA) 2-dimension fuzzy linguistic information
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2-D distributed pose estimation of multi-agent systems using bearing measurements
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作者 Xu Fang Jitao Li +1 位作者 Xiaolei Li Lihua Xie 《Journal of Automation and Intelligence》 2023年第2期70-78,共9页
This article studies distributed pose(orientation and position)estimation of leader–follower multi-agent systems over𝜅-layer graphs in 2-D plane.Only the leaders have access to their orientations and position... This article studies distributed pose(orientation and position)estimation of leader–follower multi-agent systems over𝜅-layer graphs in 2-D plane.Only the leaders have access to their orientations and positions,while the followers can measure the relative bearings or(angular and linear)velocities in their unknown local coordinate frames.For the orientation estimation,the local relative bearings are used to obtain the relative orientations among the agents,based on which a distributed orientation estimation algorithm is proposed for each follower to estimate its orientation.For the position estimation,the local relative bearings are used to obtain the position constraints among the agents,and a distributed position estimation algorithm is proposed for each follower to estimate its position by solving its position constraints.Both the orientation and position estimation errors converge to zero asymptotically.A simulation example is given to verify the theoretical results. 展开更多
关键词 Pose estimation Distributed algorithm Bearing measurements Multi-agent system Local coordinate frame 2-D plane
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A TWO-DIMENSIONAL LAGRANGIAN TECHNIQUE FOR FLOW FIELD MEASUREMENT UNDER HIGH DYNAMIC PRESSURE 被引量:5
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作者 Huan Shi (Dept.of Applied Physics Changsha Institute of Technology)Ding Jing (Dept.of Engineering Mechanics Beijing Institute of Technology) 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1990年第2期188-192,共5页
In this paper,a two-dimensional(2-D)Lagrangian technique for flow field measurement under high dynamic pressure is presented,which includes a set of experimental device and 2-D Lagrange composite manganin-constantan r... In this paper,a two-dimensional(2-D)Lagrangian technique for flow field measurement under high dynamic pressure is presented,which includes a set of experimental device and 2-D Lagrange composite manganin-constantan ring gages.With this kind of gage,the histories of pressure and radial displacement can be measured simultaneously at different Lagrange positions in an axisymmetric shock loading flow field. The technique has some advantages over the 1-D one,such as,simplified loading device,continuously adjust- able output pressure,no restriction on sample length and the availability for the study of lateral rarefaction in shock propogation.As a preliminary application,the processes of 2-D shock initiation and attenuation in compacted TNT are measured. 展开更多
关键词 Lagrange gage 2-D measurement shock initiation high velocity impact
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Effect of Measurement Time on Emission Flux of CO_2 and N_2O in Black Soil Region
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作者 乔云发 韩晓增 赵兰坡 《Agricultural Science & Technology》 CAS 2012年第2期361-364,共4页
[Objective] The aim was to investigate and reveal effect of measurement time on emission flux of CO2 and N2O to ensure the optimum time of emission flux, in order to provide scientific reference for emission reduction... [Objective] The aim was to investigate and reveal effect of measurement time on emission flux of CO2 and N2O to ensure the optimum time of emission flux, in order to provide scientific reference for emission reduction of greenhouse gas in black soil region. [Method] Based on experiment of long-term fertilizer location in black soil region, the paper studied on daily dynamic variation of CO2 and N2O discharge in 3 key growth periods (booting stage, grain-filling stage and mature stage) to reveal differences of CO2 and N2O emission flux in different times. [Result] Daily variations of CO2 and N2O emission flux were large, from 205 mg/(m2·h) to 552 mg/(m2·h) for CO2 and from 51 h to 295 μg/(m2·h) for N2O. Trend of CO2 discharge in different growth times showed a unimodal curve, and the peak was at noon of 12:00 and the peak valley was at 3:00 am; discharge of N2O was small in day time at booting stage and large at night. Regardless of rice growth period effect on CO2 and N2O emission flux, representative time of CO2 discharge was 6:00-8:00 or 16:00-21:00; and time of N2O was 8:00-10:00 or 16:00-21:00; if CO2 and N2O emission fluxes were measured simultaneously, the optimum time was 16:00-18:00; if the measurement was started during 9:00-12:00, correction coefficients of CO2 and N2O were 0.81 and 0.90, respectively. [Conclusion] The result provided scientific reference for reduction of greenhouse gas emission in black soil region. 展开更多
关键词 CO2 N2O Black soil measurement time
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49-2游泳池式轻水反应堆池底点缺陷超声测量技术研究
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作者 杨笑 张宇 +2 位作者 王硕 吴东栋 丁松 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第8期1616-1620,共5页
为掌握49-2游泳池式轻水反应堆(简称49-2堆)堆水池铝质池底点缺陷的现状,以进一步为堆水池的服役性能评估提供数据支撑,确保反应堆的安全稳定运行,根据池底结构、池内介质、池壁材料等信息,研发了水浸超声测量系统,对池底点缺陷的分布... 为掌握49-2游泳池式轻水反应堆(简称49-2堆)堆水池铝质池底点缺陷的现状,以进一步为堆水池的服役性能评估提供数据支撑,确保反应堆的安全稳定运行,根据池底结构、池内介质、池壁材料等信息,研发了水浸超声测量系统,对池底点缺陷的分布情况进行了全面检查,实现了点缺陷深度的精确测量。该研究实现了首次对49-2堆池底点缺陷实际状态的远程水下无损检测,检测结论显示:与历史数据相比,池底点缺陷的分布和点坑深度测量数据基本一致,最大点坑深度为1.495 mm。研究结论为49-2堆池底材料的时限老化分析提供了重要数据支撑,研发的水下超声测量技术也可应用于同类型池式堆堆容器及乏燃料贮存池的老化管理工作以及服役寿命分析论证工作中。 展开更多
关键词 49-2 超声检测 点缺陷
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Multi-attribute group decision making method under 2-dimension uncertain linguistic variables 被引量:3
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作者 JIANG Kexin ZHANG Quan YAN Manting 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第6期1254-1261,共8页
A method is proposed to deal with the uncertain multiple attribute group decision making problems,where 2-dimension uncertain linguistic variables(2DULVs)are used as the reliable way for the experts to express their f... A method is proposed to deal with the uncertain multiple attribute group decision making problems,where 2-dimension uncertain linguistic variables(2DULVs)are used as the reliable way for the experts to express their fuzzy subjective evaluation information.Firstly,in order to measure the 2DULVs more accurately,a new method is proposed to compare two 2DULVs,called a score function,while a new function is defined to measure the distance between two 2DULVs.Secondly,two optimization models are established to determine the weight of experts and attributes based on the new distance formula and a weighted average operator is used to determine the comprehensive evaluation value of each alternative.Then,a score function is used to determine the ranking of the alternatives.Finally,the effectiveness of the proposed method is proved by an illustrated example. 展开更多
关键词 2-dimension uncertain linguistic variables(2DULVs) multi-attribute group decision making problem score function distance formula
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Comparing different light-emitting diodes as light sources for long path differential optical absorption spectroscopy NO_2 and SO_2 measurements 被引量:1
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作者 陈嘉乐 凌六一 +7 位作者 Andreas Hartl 郑尼娜 Gerrit Kuhlmann 秦敏 孙友文 谢品华 刘文清 Mark Wenig 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期587-596,共10页
In this paper, we present a comparison of different light-emitting diodes (LEDs) as the light source for long path differential optical absorption spectroscopy (LP-DOAS) atmospheric trace gas measurements. In our ... In this paper, we present a comparison of different light-emitting diodes (LEDs) as the light source for long path differential optical absorption spectroscopy (LP-DOAS) atmospheric trace gas measurements. In our study, we use a fiberoptic design, where high power LEDs used as the light source are coupled into the telescope using a Y shape fiber bundle. Two blue and one ultraviolet (UV) LEDs with different emission wavelength ranges are tested for NO2 and SO2 measurements. The detailed description of the instrumental setup, the NO2 and SO2 retrieval procedure, the error analysis, and the preliminary results from the measurements carried out in Science Island, Hefei, Anhui, China are presented. Our first measurement results show that atmospheric NO2 and SO2 have strong temporal variations in that area and that the measurement accuracy is strongly dependent on the visibility conditions. The measured NO2 and SO2 data are compared to the Ozone Monitoring Instrument (OMI) satellite observations. The results show that the OMI NO2 product underestimates the ground level NO2 by 45%, while the OMI SO2 data are highly influenced by clouds and aerosols, which can lead to large biases in the ground level concentrations. During the experiment, the mixing ratios of the atmospheric NO2 and SO2 vary from 8 ppbv to 36 ppbv and from 3 ppbv to 18 ppbv, respectively. 展开更多
关键词 light-emitting diode fiber optic designed telescope NO2 measurement SO2 measurement
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A low-cost in-situ CO_(2) sensor based on a membrane and NDIR for long-term measurement in seawater 被引量:2
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作者 Meng LI Baolu DU +3 位作者 Jinjia GUO Zhihao ZHANG Zeyu LU Rong’er ZHENG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第3期986-998,共13页
The multi-point simultaneous long-term measurement of CO_(2) concentration in seawater can provide more-valuable data for further understanding of the spatial and temporal distribution of CO_(2).Thus,the requirement f... The multi-point simultaneous long-term measurement of CO_(2) concentration in seawater can provide more-valuable data for further understanding of the spatial and temporal distribution of CO_(2).Thus,the requirement for a low-cost sensor with high precision,low power consumption,and a small size is becoming urgent.In this work,an in-situ sensor for CO_(2) detection in seawater,based on a permeable membrane and non-dispersive infrared(NDIR)technology,is developed.The sensor has a small size(Ф66 mm×124 mm),light weight(0.7 kg in air),low power consumption(<0.9 W),low cost(<US$1000),and high-pressure tolerance(<200 m).After laboratory performance tests,the sensor was found to have a measurement range of(0–2000)×10^(-6),and the gas linear correlation R^(2) is 0.99,with a precision of about 0.98%at a sampling rate of 1 s.A comparison measurement was carried out with a commercial sensor in a pool for 7 days,and the results showed a consistent trend.Further,the newly developed sensor was deployed in Qingdao nearshore water for 35 days.The results proved that the sensor could measure the dynamic changes of CO_(2) concentration in seawater continuously,and had the potential to carry out long-term observations on an oceanic platform.It is hoped that the sensor could be applied to field ocean observations in near future. 展开更多
关键词 in-situ sensor dissolved CO_(2) long-term measurement permeable membrane non-dispersive infrared(NDIR) LOW-COST
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Multisoliton Solutions of the (2+1)-Dimensional KdV Equation 被引量:1
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作者 ZHANG Jie-Fang HUANG Wen-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第11期523-524,共2页
Using the extension homogeneous balance method,we have obtained some new special types of soliton solutions of the (2+1)-dimensional KdV equation.Starting from the homogeneous balance method,one can obtain a nonlinear... Using the extension homogeneous balance method,we have obtained some new special types of soliton solutions of the (2+1)-dimensional KdV equation.Starting from the homogeneous balance method,one can obtain a nonlinear transformation to simple (2+1)-dimensional KdV equation into a linear partial differential equation and two bilinear partial differential equations.Usually,one can obtain only a kind of soliton-like solutions.In this letter,we find further some special types of the multisoliton solutions from the linear and bilinear partial differential equations. 展开更多
关键词 multisoliton (2+1)-dimensions KdV EQUATION
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改性色谱柱分离辐照后UO_(2)-Zr燃料中燃耗监测体钕的方法研究
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作者 彭曼舒 胡银 +5 位作者 冯伟伟 曹骐 陈云明 王鹏 王定娜 王奇龙 《化学研究与应用》 CAS 北大核心 2024年第4期760-765,共6页
钕监测体法整体精度高、适用范围广,是目前最常用的绝对燃耗测量方法之一。新型UO_(2)-Zr燃料中锆基体为燃料的溶解及燃耗监测体钕的分离带来了极大挑战,钕分离效率的提高对提升绝对燃耗测量可靠性、降低操作人员受照剂量具有重要意义... 钕监测体法整体精度高、适用范围广,是目前最常用的绝对燃耗测量方法之一。新型UO_(2)-Zr燃料中锆基体为燃料的溶解及燃耗监测体钕的分离带来了极大挑战,钕分离效率的提高对提升绝对燃耗测量可靠性、降低操作人员受照剂量具有重要意义。选择三种具有较强镧系元素萃取能力的酸性磷类萃取剂作为改性试剂,通过浸渍法完成商业化色谱柱的改性制备。比较研究表明,(2-乙基己基)膦酸单-2-乙基己基酯改性后的色谱柱分离性能最优,在0.05 mol·L^(-1)硝酸溶液的等度洗脱下,15 min内可实现钕的完全分离,Pr/Nd分离因子为1.73,而Nd/Sm分离因子远远大于1.5。60次重复分离实验证实改性色谱柱分离稳定性良好,在模拟辐照后UO_(2)-Zr燃料溶液中能实现大量铀、锆基体中微量钕的富集与分离。 展开更多
关键词 燃耗测量 色谱柱改性 钕监测体 有机磷类萃取剂 UO_(2)-Zr燃料
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基于TDLAS的H_(2)S气体材料表面吸附特性研究
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作者 金建新 刘威 +3 位作者 宋振明 朱志辉 田冰 彭志敏 《激光与红外》 CAS CSCD 北大核心 2024年第5期710-717,共8页
在H_(2)S气体浓度在线监测过程中,因其具有粘附性强的特点,容易发生管线吸附,从而导致测量结果存在偏差,尤其在痕量H_(2)S检测过程中表现最为明显,所以开展H_(2)S气体管线材料表面吸附特性研究尤为必要。本文基于可调谐二极管激光吸收... 在H_(2)S气体浓度在线监测过程中,因其具有粘附性强的特点,容易发生管线吸附,从而导致测量结果存在偏差,尤其在痕量H_(2)S检测过程中表现最为明显,所以开展H_(2)S气体管线材料表面吸附特性研究尤为必要。本文基于可调谐二极管激光吸收光谱技术(TDLAS),设计并搭建了一套H_(2)S浓度在线测定系统,并对该系统进行了测量性能检验,在此基础上进行了H_(2)S在不锈钢材料表面常温吸附特性探究。实验结果表明,所搭建H_(2)S浓度在线测定系统具有稳定性强、检测限低和灵敏度高的特点,利用此系统可以实现痕量H_(2)S浓度的在线连续测定。经过一系列探究试验,证明了H_(2)S在不锈钢材料表面存在明显且稳定的吸附作用,得出了H_(2)S在不锈钢材料表面的单位面积吸附量在10^(14)(个/cm^(2))量级。实验结果可以为痕量硫化氢在线精准测量提供一定参考。 展开更多
关键词 TDLAS H_(2)S 测量系统 材料表面 吸附特性
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Development of 2D Temperature and Concentration Measurement Method Using Tunable Diode Laser Absorption Spectroscopy 被引量:7
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作者 Yoshihiro Deguchi Daisuke Yasui Akira Adachi 《Journal of Mechanics Engineering and Automation》 2012年第9期543-549,共7页
Exhaust gas temperature is an important factor in NOx, THC and PM emissions of engines. Especially 2D temperature and concentration distribution plays an important role for the engine efficiency. A thermocouple is int... Exhaust gas temperature is an important factor in NOx, THC and PM emissions of engines. Especially 2D temperature and concentration distribution plays an important role for the engine efficiency. A thermocouple is intrinsically a point temperature measurement method and noncontact 2D temperature distribution cannot be attained by thermocouples. Recently, as a measurement technique with high sensitivity and high response, laser diagnostics has been developed and applied to the actual engine combustions. With these engineering developments, transient phenomena such as start-ups and load changes in engines have been gradually elucidated in various conditions. In this study, the theoretical and experimental research has been conducted in order to develop the noncontact and fast response 2D temperature and concentration distribution measurement method. The method is based on a Computed Tomography (CT) method using absorption spectra of water vapor at 1388 nm. It has been demonstrated that the method has been successfully applied to engine exhausts to measure 2D temperature distributions. 展开更多
关键词 2D temperature measurement tunable diode laser absorption spectroscopy CT (computed tomography) engine exhausts.
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2型糖尿病住院患者核心护理标准化语言的构建
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作者 靳荣秀 郭晶晶 +1 位作者 刘素琼 彭卫群 《中华护理教育》 CSCD 2024年第7期887-891,共5页
目的构建2型糖尿病住院患者核心护理标准化语言,为规范临床护理记录提供参考。方法聚焦2型糖尿病住院患者的护理,通过文献检索、回顾医院护理记录及专家咨询确定2型糖尿病住院患者核心护理诊断,通过“国际北美护理诊断协会分类(North Am... 目的构建2型糖尿病住院患者核心护理标准化语言,为规范临床护理记录提供参考。方法聚焦2型糖尿病住院患者的护理,通过文献检索、回顾医院护理记录及专家咨询确定2型糖尿病住院患者核心护理诊断,通过“国际北美护理诊断协会分类(North American Nursing Diagnosis Association International,NANDA-Ⅰ)、护理措施分类(Nursing Interventions Classification,NIC)、护理结局分类(Nursing Outcomes Classification,NOC)”(简称NNN链接)初步筛选核心护理诊断所匹配的核心护理结局、护理指标及核心护理措施、护理活动,邀请21名专家进行2轮函询进行修订完善,最终形成2型糖尿病住院患者核心护理标准化语言。结果2型糖尿病住院患者核心护理标准化语言包括6项护理诊断、11项护理结局(52项护理指标)、15项护理措施(126项护理活动)。结论本研究构建的2型糖尿病住院患者核心护理标准化语言符合我国国情、文化背景、语言理解及临床实践,具有专业性、科学性,有利于实现护理语言的标准化,提升糖尿病专科护理质量。 展开更多
关键词 糖尿病 2 护理诊断 护理结局分类 护理措施分类
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徐州市不同行业CO_(2)排放量测算及减排措施
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作者 张娜 张谷春 +6 位作者 王双美 王伟 徐辉 马萍 朱燕 吴蒙 陈飞 《能源与节能》 2024年第1期81-86,共6页
在城市发展过程中,准确计算城市碳排放量对优化和指导CO_(2)减排路径至关重要。通过收集26年的徐州统计年鉴,运用碳排放因子法计算了徐州市化石能源、家庭燃气、水泥、钢铁、化工、电力和交通运输的CO_(2)排放量。结果发现徐州市1995—2... 在城市发展过程中,准确计算城市碳排放量对优化和指导CO_(2)减排路径至关重要。通过收集26年的徐州统计年鉴,运用碳排放因子法计算了徐州市化石能源、家庭燃气、水泥、钢铁、化工、电力和交通运输的CO_(2)排放量。结果发现徐州市1995—2020年各行业CO_(2)排放量情况为:化石能源消费CO_(2)排放量为2.765 18×10^(7)~1.335 63×108t,家庭燃气CO_(2)排放量为0.931×10^(5)~5.275×10^(5)t,水泥行业CO_(2)排放量为1.050 185×10^(7)~3.894 500×10^(7)t,钢铁行业CO_(2)排放量为0.565 9×10^(6)~8.195 7×10^(6)t,化工行业CO_(2)排放量为0.722 8×10^(6)~4.411 4×10^(6)t,电力行业CO_(2)排放量为0.690 87×10^(7)~3.339 01×10^(7)t,交通运输CO_(2)排放量为0.658 0×10^(6)~7.340 3×10^(6)t。徐州市政府应根据各行业CO_(2)排放特点,从加大政策扶持、加强碳汇利用、倡导低碳发展和研发清洁能源等角度合理制定减碳措施。 展开更多
关键词 徐州市 CO_(2)排放 排放因子 减排措施
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基于TDLAS的H_(2)S高温反应特性实验研究
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作者 王嘉琦 田思迪 +3 位作者 高东波 田志伟 彭志敏 杜艳君 《热力发电》 CAS CSCD 北大核心 2024年第2期162-169,共8页
电站锅炉在低NO_(x)燃烧过程中因锅炉内还原性气氛浓度较高,会产生较多H_(2)S气体。针对H_(2)S因具有易燃、强腐蚀性、剧毒性而可能对火电厂造成多种危害的问题,采用可调谐二极管激光吸收光谱(tunable diode laser absorption spectrosc... 电站锅炉在低NO_(x)燃烧过程中因锅炉内还原性气氛浓度较高,会产生较多H_(2)S气体。针对H_(2)S因具有易燃、强腐蚀性、剧毒性而可能对火电厂造成多种危害的问题,采用可调谐二极管激光吸收光谱(tunable diode laser absorption spectroscopy,TDLAS)方法结合多通池和计算机搭建低气体摩尔分数在线测量系统,实现了对混合气体中摩尔分数在10–6量级H_(2)S的精确在线测量,并利用该测量系统进行了H_(2)S高温反应实验,探究实验温度和混合气体中O_(2)摩尔分数对该反应的影响。实验结果展示了压力为80 kPa、O_(2)摩尔分数为0~5%的条件下,H_(2)S开始发生化学反应的温度随O_(2)摩尔分数变化的变化规律,整体而言,混合气体中O_(2)摩尔分数越高,H_(2)S开始发生化学反应的温度越低。实验结果可以为锅炉烟气中H_(2)S的生成、转化和危害控制提供一定数据基础。 展开更多
关键词 TDLAS H_(2)S 在线测量 高温反应 O_(2)摩尔分数
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基于激光吸收光谱的CO/CO_(2)/H_(2)S浓度同步在线测量研究
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作者 张学军 陈勤根 +3 位作者 杨展 邓琴 贺拴玲 彭志敏 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第5期1412-1416,共5页
CO、CO_(2)、H_(2)S是燃煤锅炉炉内气氛重要组成部分,其浓度不仅能够反映燃烧工况,还可作为水冷壁高温腐蚀程度判断依据,因此实现CO、CO_(2)、H_(2)S浓度的准确测量意义重大。首先采用波长调制-直接吸收(WM-DAS)方法结合约40 m长光程Her... CO、CO_(2)、H_(2)S是燃煤锅炉炉内气氛重要组成部分,其浓度不仅能够反映燃烧工况,还可作为水冷壁高温腐蚀程度判断依据,因此实现CO、CO_(2)、H_(2)S浓度的准确测量意义重大。首先采用波长调制-直接吸收(WM-DAS)方法结合约40 m长光程Herriott池,在室温低压下,开展不同CO/CO_(2)浓度配比下三种气体吸收率同步测量实验,结果表明三种气体的吸收率测量值与理论计算值相近,相对误差在6.82%以内,测量结果可靠性较高;然后对不同浓度CO/CO_(2)(0~2000μL·L^(-1))、H_(2)S(0~20μL·L^(-1))进行动态测量,结果表明,测量系统对三种组分浓度变化的响应具有较好的线性度。 展开更多
关键词 波长调制-直接吸收光谱 CO浓度 CO_(2)浓度 H_(2)S浓度 同步测量
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基于CO_(2)排放量检测的秸秆腐解动态监测系统研究
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作者 李奇辰 霍丽丽 +2 位作者 姚宗路 赵立欣 杉原敏昭 《农业机械学报》 EI CAS CSCD 北大核心 2024年第10期399-409,共11页
针对秸秆腐解产物复杂,导致在线监测困难的问题,提出以秸秆腐解CO_(2)排放量作为反映秸秆腐解动态特性的指标。并针对市面CO_(2)传感器成本高、体积大,在秸秆腐解监测中普及困难的问题,基于小型、低成本非色散红外(Non-dispersive infra... 针对秸秆腐解产物复杂,导致在线监测困难的问题,提出以秸秆腐解CO_(2)排放量作为反映秸秆腐解动态特性的指标。并针对市面CO_(2)传感器成本高、体积大,在秸秆腐解监测中普及困难的问题,基于小型、低成本非色散红外(Non-dispersive infrared,NDIR)CO_(2)传感器、环境传感器及Arduino板,设计了秸秆腐解动态监测系统,实现秸秆腐解过程环境参数、秸秆温度以及CO_(2)浓度多位点的监测,并结合微生物群落数据,分析了秸秆腐解规律。以市面TR-76Ui CO_(2)记录仪为基准,对每个低成本NDIR CO_(2)传感器进行测试与校准,1829个数据点的线性回归模型决定系数R^(2)为0.97~0.99,RMSE为14.56~56.36μL/L,表明低成本NDIR CO_(2)传感器具有良好的检测精度和稳定性。秸秆堆体内部CO_(2)浓度具有周期性变化规律,变化趋势与温度的变化趋势一致,且振动幅度随秸秆干燥逐渐减弱,该现象反映了微生物活动的生物节律,揭示了秸秆堆体内部CO_(2)变化能够反映秸秆腐解的行为特征。分析表明,秸秆腐解速率与温度和含水率呈正相关,决定系数R^(2)分别为0.8137与0.892。调节秸秆含水率大于40%后,秸秆腐解速率迅速下降,至第4天趋于平稳。添加微生物菌剂后秸秆腐解速率在第7天开始明显下降,至第12天开始趋于平稳。监测周期内传感器未发生明显漂移,有较好的稳定性,检测精度可以满足秸秆腐解试验的分析需求,小型、低成本硬件对于秸秆腐解动态监测具有很好的推广应用潜力。 展开更多
关键词 秸秆CO_(2)排放 腐解动态监测系统 ARDUINO 高时空分辨率监测
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基于深度学习的烟气温度和CO_(2)浓度在线检测
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作者 周颖 娄春 马晓春 《洁净煤技术》 CAS CSCD 北大核心 2024年第8期50-57,共8页
基于低分辨率红外发射光谱采集技术,耦合深度学习计算方法,提出了一种烟气温度和CO_(2)浓度在线检测方法。利用气体光谱辐射模型计算训练数据,基于多层感知器(MLP)神经网络反演火焰烟气温度和CO_(2)浓度的分布,结果表明,MLP神经网络模... 基于低分辨率红外发射光谱采集技术,耦合深度学习计算方法,提出了一种烟气温度和CO_(2)浓度在线检测方法。利用气体光谱辐射模型计算训练数据,基于多层感知器(MLP)神经网络反演火焰烟气温度和CO_(2)浓度的分布,结果表明,MLP神经网络模型对温度、CO_(2)和H_(2)O体积分数的反演误差均低于1%,预测精度均大于94.5%,具有良好的泛化能力和预测能力。建立了一套基于深度学习与发射光谱耦合的烟气温度和CO_(2)浓度在线检测装置,并对乙烯扩散火焰和C_(2)H_(4)/NH_(3)部分预混火焰展开了研究。乙烯扩散火焰烟气温度和CO_(2)体积分数的测量结果与模拟火焰结果相一致,验证了基于深度学习与发射光谱耦合的在线检测法的可行性。改变部分预混火焰的掺氨比例,分析火焰中轴上方不同高度处气体的温度和CO_(2)浓度变化,结果表明,同一高度处的烟气温度会随着掺入氨气的增加而增大,而CO_(2)体积分数会呈先增大后急剧减少的趋势。所提出的方法可以较灵敏的检测温度和CO_(2)浓度的变化,用于多种火焰的燃烧诊断研究,在燃煤电厂碳排放在线检测上也有一定的应用前景。 展开更多
关键词 燃烧火焰 CO_(2) 在线检测 红外光谱分析 多层感知器 气体温度
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Research Progress on Self-Efficacy Level of Patients with Type 2 Diabetes Mellitus and Its Influencing Factors
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作者 Peiling Li Juanjuan Guo 《Open Journal of Preventive Medicine》 2024年第5期79-89,共11页
Self-efficacy plays an important role in the management of type 2 diabetes mellitus (T2DM) patients, and it runs through the whole process of diabetes treatment, which is conducive to controlling and delaying the occu... Self-efficacy plays an important role in the management of type 2 diabetes mellitus (T2DM) patients, and it runs through the whole process of diabetes treatment, which is conducive to controlling and delaying the occurrence and development of complications, as well as improving the quality of life of patients. This paper mainly describes the concept of self-efficacy, the current situation of self-efficacy of diabetic patients at home and abroad, the functional aspects and their influencing factors, so as to take relevant measures on how to improve self-efficacy. It aims to provide a theoretical basis for the development of self-efficacy interventions for patients with type 2 diabetes mellitus. 展开更多
关键词 Type 2 Diabetes SELF-EFFICACY Influencing Factors measures
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