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具有时滞效应的air2stream河流水温模型及应用研究
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作者 李凌波 王启明 +3 位作者 赵忠伟 唐玉川 李成明 胡艳 《水文》 CSCD 北大核心 2024年第4期45-51,共7页
高精度河流水温模型对于深入了解水温的时空变化特征和河流生态修复具有重要意义。基于数据驱动的air2stream模型在保证预测精度的同时,避免了计算的复杂性,已成为河流水温模拟常用的模型。由于水的热惯性及水文条件等的影响,河流水温... 高精度河流水温模型对于深入了解水温的时空变化特征和河流生态修复具有重要意义。基于数据驱动的air2stream模型在保证预测精度的同时,避免了计算的复杂性,已成为河流水温模拟常用的模型。由于水的热惯性及水文条件等的影响,河流水温变化往往显著滞后于气温变化,而air2stream原模型并未考虑滞后效应,导致该模型在流量未知情况下实际精度偏低。为解决该问题,采用气温-水温皮尔逊相关系数计算时滞天数,构建具有时滞的air2stream新模型,进一步根据长江中下游地区两个监测站的多年实测数据验证新模型的有效性和稳定性。结果表明:新模型在不引进额外观测数据的条件下具有更高精度且性能更稳定。相比原模型,在两个监测站新模型的均方根误差分别降低约4.29%和5.85%。新模型具有精度高、水文要素需求少的特点,可为长江中下游的水环境影响评价和生态保护提供依据。 展开更多
关键词 气温-水温模型 时滞 air2stream 长江中下游水温
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高温环境因素对固-液混合燃料物理稳定性的影响
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作者 张弛 付豪 +2 位作者 宋戈 石睿捷 白春华 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第9期9-16,共8页
固-液混合燃料的物理稳定性对于燃料的质量和安全性均有重要的意义。高温环境引发的易挥发液体组分的气化将对燃料的物理稳定性产生极为复杂的影响。通过自主设计的实验装置模拟、加速燃料物理稳定性改变,并分别从液体燃料析出及密度分... 固-液混合燃料的物理稳定性对于燃料的质量和安全性均有重要的意义。高温环境引发的易挥发液体组分的气化将对燃料的物理稳定性产生极为复杂的影响。通过自主设计的实验装置模拟、加速燃料物理稳定性改变,并分别从液体燃料析出及密度分布变化趋势,分析高温环境因素的作用。结果表明:自然堆垛状态下燃料的顶部受饱和蒸汽压的改变影响较大,而中部、底部则由于燃料的紧密堆积,形成各自独立的气液平衡。同时,液体燃料于高温环境中对固体的润湿效果随之增强,更有利于液体组分完成对固体颗粒的吸附。在303~333 K的温度条件下,固液体积比为1.25∶1,硝基甲烷占液体组分40%的固-液混合燃料保持最佳的物理稳定性。 展开更多
关键词 -液混合燃料 温度因素 物理稳定性 FAE(fuel air explosive)
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组合称重法与分压法的C_(5)F_(10)O-PFK/Air混气制备技术研究 被引量:3
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作者 朱会 齐汝宾 +3 位作者 曾晓哲 赫树开 吴倩倩 侯新梅 《化学试剂》 CAS 北大核心 2021年第1期89-93,共5页
制备高精度的C5-PFK/Air混合气体有利于实现对C5-PFK气体-电气性能的科学论证。采用称重法与分压法实现了对不同混合比的C5-PFK/Air混合气体的制备,搭建C5-PFK/Air混气制备实验系统,建立了气相色谱-氢火焰离子化检测器(GC-FID)对制备的C... 制备高精度的C5-PFK/Air混合气体有利于实现对C5-PFK气体-电气性能的科学论证。采用称重法与分压法实现了对不同混合比的C5-PFK/Air混合气体的制备,搭建C5-PFK/Air混气制备实验系统,建立了气相色谱-氢火焰离子化检测器(GC-FID)对制备的C5-PFK/Air混气中C5-PFK定性定量分析的仪器方法,可对实验结果进行溯源校准。研究结果表明,制备13%C5-PFK/Air混合气体的RSD为0.89%,最大示值误差为0.77%;压力为0.5 MPa时,12%~15%浓度范围内C5-PFK/Air混气中C5-PFK峰面积线性拟合系数R^(2)为0.995,一致性良好,可完全汽化;6个月的稳定性考察,气体特性值保持不变,稳定性良好。 展开更多
关键词 称重法 分压法 气相色谱-氢火焰离子化检测器 重复性 均匀性 稳定性 C5-PFK/air
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The Application of Air-flow to the Technological Process of Chemical Fiber
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作者 崔启亮 陈明 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期112-114,共3页
The air-flow’s states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bul... The air-flow’s states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bulked continuous filament (BCF)),and the effect of air-flow on the process and quality of chemical fiber is studied,and the action of mechanics and heat on the bulked continuous filament are calculated. 展开更多
关键词 air - flow CHEMICAL FIBER TECHNOLOGICAL process
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Air-flow Analysis for BCF Texturing Tube
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作者 崔启亮 陈明 陈人哲 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期114-116,共3页
In this paper,the Reynolds number,velocity,pressureand kinetic energy of the BCF processing hot air-floware analyzed with the help of the aero-dynamic theory,and their distributions inside the texturing tube are ob-ta... In this paper,the Reynolds number,velocity,pressureand kinetic energy of the BCF processing hot air-floware analyzed with the help of the aero-dynamic theory,and their distributions inside the texturing tube are ob-tained by pressure measuring. 展开更多
关键词 TEXTURING unit TEXTURING TUBE air - flow.
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Air Quality Regarding to TSP in Six Cities of Sonora,Mexico,a Criticism to the NOM-025-SSA1-1993 and a Proposed Criterion for Its Non-Compliance
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作者 Martin Eusebio Cruz-Campas Agustin Gomez-Alvarez +3 位作者 Margarito Quintero-Nunez Roberto Ramirez-Leal Jaime Varela-Salazar Onofre Monge-Amaya 《Journal of Environmental Protection》 2014年第10期862-873,共12页
In the present study, the air quality is assessed for the year 2010 regarding to the Total Suspended Particles (TSP) for six cities of Sonora, Mexico, representing the first regional study in Sonora in air quality. Th... In the present study, the air quality is assessed for the year 2010 regarding to the Total Suspended Particles (TSP) for six cities of Sonora, Mexico, representing the first regional study in Sonora in air quality. The assessment used performance indicators and indicators of compliance with the regulations. It is established that in all the cities the maximum limit value of daily concentration of 210 μg/m3 is exceeded, being the percentage of days above the rule of 30%, 78%, 76%, 6%, 3% and 62% for Agua Prieta, Nogales, Puerto Penasco, Hermosillo, Guaymas and Obregón respectively, classifying these days with poor air quality. According to the annualized index used, the air quality was not satisfactory for the period of study in the six cities. Nogales and Puerto Penasco presented the most adverse conditions of air quality with annual average values of TSP of 363 and 345 μg/m3 and maximum daily of 1047 and 1239 μg/m3 (498% and 590% above the norm) respectively. The requirements of coverage that establishes the Mexican Official Standard NOM-025-SSA1-1993 (SSA, 2005) are questioned for its compliance, proposing in this paper a criterion of non-compliance by prioritizing the protection of health and the precautionary principle. It is recommended to implement air quality management programs (PROAIRE) in these cities. 展开更多
关键词 Particles TSP air Quality NOM-025-SSA1-1993 Sonora Mexico
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预浓缩系统与GC-MS联用测定环境空气中痕量挥发性有机物 被引量:20
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作者 徐能斌 应红梅 +1 位作者 朱丽波 俞杰 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期198-201,205,共5页
  目前,国内空气质量监测普遍停留在燃煤、汽车尾气引起的无机污染物(二氧化硫、二氧化氮)阶段,而对易对人体产生三致作用(致癌、致畸、致突变)的挥发性有机物(VOCs)监测由于技术原因尚未开展.现在,挥发性有机物(VOCs)对室内外空气质...   目前,国内空气质量监测普遍停留在燃煤、汽车尾气引起的无机污染物(二氧化硫、二氧化氮)阶段,而对易对人体产生三致作用(致癌、致畸、致突变)的挥发性有机物(VOCs)监测由于技术原因尚未开展.现在,挥发性有机物(VOCs)对室内外空气质量及人体健康的影响已日益受到人们的关注,同时也成为国内外研究的焦点.…… 展开更多
关键词 VOCS GC - MS Ambient air
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IGF-ⅠR抑制剂联合西妥昔单抗对人肝癌细胞的体外抑制作用 被引量:2
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作者 韩春蕃 陈莹蓉 +6 位作者 蔡炜龙 谢忠海 王雁 沈华 闵丽姗 魏锋 戴利成 《中国现代医生》 2012年第26期1-3,共3页
目的探讨西妥昔单抗与胰岛素样生长因子-Ⅰ受体(IGF-ⅠR)抑制剂aIR3对人肝癌细胞株HepG2细胞的作用。方法选用浓度递增的西妥昔单抗(5-500)mg/mL和aIR3(2.5~250.0)μmol/L,单独或联合作用于HepG2细胞,观察不同时间对细胞... 目的探讨西妥昔单抗与胰岛素样生长因子-Ⅰ受体(IGF-ⅠR)抑制剂aIR3对人肝癌细胞株HepG2细胞的作用。方法选用浓度递增的西妥昔单抗(5-500)mg/mL和aIR3(2.5~250.0)μmol/L,单独或联合作用于HepG2细胞,观察不同时间对细胞增殖的抑制作用以及联用时的两药协同系数。结果单药西妥昔单抗与aIR3对HepG2细胞增殖的抑制作用均呈浓度依赖性与时间依赖性,二药单独作用于HepG2细胞72h最大抑制率分别为42.2%、82.3%,二药联合作用于HepG2细胞72h最大抑制率达91.8%。西妥昔单抗与aIR3不同浓度在各时间点的协同系数均小于1。结论西妥昔单抗和aIR3在体外对HepG2细胞的增殖均具有一定的抑制作用,联合应用时具有明显的协同效应。 展开更多
关键词 肝癌细胞株 表皮生长因子受体 西妥昔单抗 胰岛素样生长因子-Ⅰ受体 air3
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Sub seasonal variations of weak stratospheric polar vortex in December and its impact on Eurasian air temperature 被引量:1
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作者 PENG Cheng FAN Ke DAI Haixia 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第5期369-375,共7页
Weak stratospheric polar vortex(WPV)events during winter months were investigated.WPV events were identified as being weakest in December,accompanied by the most dramatic increase in geopotential height over the polar... Weak stratospheric polar vortex(WPV)events during winter months were investigated.WPV events were identified as being weakest in December,accompanied by the most dramatic increase in geopotential height over the polar region.After the onset of a December WPV event,the dynamic processes influencing Eurasian temperature can be split into two separate periods.Period I(lag of 0-25 days)is referred to as the stratosphere-troposphere interactions period,as it is mainly characterized by stratospheric signals propagating downwards.In Period I,a stratospheric negative Northern Annular Mode(NAM)pattern associated with the WPV propagates downwards,inducing a negative NAM in the troposphere.The anomalous low centers over the Mediterranean and North Pacific bring cold advection to northern Eurasia,resulting in a north-cold-south-warm dipole pattern over Eurasia.The zero line between negative and positive temperature anomalies moves southwards during days 5-20.Stratospheric cold anomalies at midlatitudes propagate downwards to high latitudes in the troposphere and contribute to the dipole structure.During PeriodⅡ(lag of 25-40 days),as downward signals from the stratosphere have vanished,the dynamic processes mainly take place within the troposphere.Specifically,a wave train is initiated from the North Atlantic region to northern Europe.The propagation of wave activity flux intensifies a cyclonic anomaly over northern Europe,which brings cold advection to Scandinavia and warm advection to central Asia.Therefore,a northwest-cold-southeast-warm dipole structure occupies Eurasia and migrates southeastwards during this period. 展开更多
关键词 Stratospheric polar vortex weak stratospheric polar vortex events in December subseasonal variability stratosphere-troposphere interaction winter Eurasian air temperature(0-40 days)
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Study on the Factors to Influence Dynamic Heat - moisture Comfort of Summer Clothing Fabrics
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作者 蒋培清 唐世君 谌玉红 《Journal of China Textile University(English Edition)》 EI CAS 1999年第2期72-76,共5页
In this paper, the factors to influence the dynamic heat - moisture comfort of summer clothing fabrics have been studied. It is pointed out that, when the wind speed outside is high, or the air permeability is very go... In this paper, the factors to influence the dynamic heat - moisture comfort of summer clothing fabrics have been studied. It is pointed out that, when the wind speed outside is high, or the air permeability is very good, the sweat of human body will evaporate mainly through turbulent diffusion. Because of the rapid sweat evaporation, human body will feel cold, and then, the difference in temperature and humidity of the micro - climatic section will be very slight. On the contrary, when the wind speed outside is slow or the air permeability is unsatisfactory, the sweat of human body will evaporate mainly through molecular diffusion, and in this case, the humidity of the micro - climatic section will be depended on the hygroscopicity of the fabric, that’ s to say, the better the hygroscopicity, the lower the humidity. It is difficult for pure wool fabric to loss heat because of its giving out much heat during the course of moisture - absorption in the initial stages of sweating. For pure polyester fabric, 展开更多
关键词 summer clothing fabric DYNAMIC HEAT - MOISTURE COMFORT air permeability HYGROSCOPICITY turbulent DIFFUSION molecular diffusion.
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SYNTHESIS,CHARACTERIZATION,THERMAL DEGRADATION AND ELECTRICAL CONDUCTIVITY OF OLIGO[2-(2-HYDROXYPHENYLIMINOMETHYLBENZYLIDENE)AMINOPHENOL]AND OLIGOMER-METAL COMPLEXES
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作者 Ismet Kaya Süleyman Çulhaoglu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第2期131-143,共13页
The oxidative polycondensation reaction conditions of 2-[(2-hydroxyphenyliminomethylbenzylidene)amino- phenol](2-HPIMBAP)has been accomplished by using air O_2 and NaOCl oxidants in an aqueous alkaline medium between ... The oxidative polycondensation reaction conditions of 2-[(2-hydroxyphenyliminomethylbenzylidene)amino- phenol](2-HPIMBAP)has been accomplished by using air O_2 and NaOCl oxidants in an aqueous alkaline medium between 50-90℃.The optimum reaction conditions of the oxidative polycondensation and the main parameters of the process were established.At the optimum reaction conditions,yield of the products were found to be 67.72% and 61.49% for air O_2 and NaOCl oxidants respectively.The structures of the monomer ... 展开更多
关键词 air oxygen NAOCL Oligo[2-(2-hydroxyphenyliminomethylbenzylidene)aminophenol] Oxidative polycondensation Themal analysis Electrical conductivity Antibacterial activities.
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SYNTHESIS,CHARACTERIZATION AND ANTIMICROBIAL PROPERTIES OF 4-[(4-HYDROXYBENZYLIDENE)AMINO]PHENOL AND ITS POLYMER
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作者 Ismet Kaya Suleyman Culhaoglu Dilek Senol 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第5期461-472,共12页
The oxidative polycondensation reaction conditions of 4-[(4-hydroxybenzylidene) amino] phenol (4-HBAP) were studied with H2O2, air oxygen and NaOCl in an aqueous alkaline medium between 50 and 90℃. The structures... The oxidative polycondensation reaction conditions of 4-[(4-hydroxybenzylidene) amino] phenol (4-HBAP) were studied with H2O2, air oxygen and NaOCl in an aqueous alkaline medium between 50 and 90℃. The structures of the obtained monomer and polymer were confirmed by FT-IR, UV-Vis, 1H- and 13C-NMR and elemental analysis. The characterization was made by TG-DTA, size exclusion chromatography (SEC) and solubility tests. At the optimum reaction conditions, the yield of poly[4-(4-hydroxybenzylidene amino) phenol] (P-4-HBAP) was found to be 48.3% (for H2O2 oxidant), 80.5% (for air O2 oxidant) and 86.4% (for NaOCl oxidant). According to the SEC analysis, the number-average molecular weight (Mn), weight-average molecular weight (Mw) and polydispersity index (PDI) values of P-4-HBAP was found to be 8950, 10970 g tool^-1 and 1.225, respectively, using H202; and l l610, 15190 g tool^-1 and 1.308 respectively, using air 02 and 7900, 9610 g mol^-1 and 1.216, respectively, using NaOC1. According to TG-DTA analyses, P-4-HBAP was more stable than 4-HBAP against thermal decomposition. The weight loss of P-4-HBAP was found to be 49.27% at 1000℃. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) values calculated from electrochemical measurement. Electrochemical energy gaps (Eg') of 4-HBAP and P-4-HBAP were found to be -5.46, -5.28; -2.26, -2.67; 3.20 and 2.61 eV, respectively. According to UV-Vis measurements, optical band gap (Eg) of 4-HBAP and P-4-HBAP were found to be 3.34 and 3.01 eV, respectively. Also, antimicrobial activities of 4-HBAP and P-4-HBAP were examined against selected some bacteria. The electrical conductivity of the polymer was measured after doping with iodine. 展开更多
关键词 air oxygen H2O2 NAOCL Poly[4-(4-hydroxybenzylidene amino) phenol] Oxidative polycondensation Thermal analysis CONDUCTIVITY Antimicrobial and bad gap.
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SYNTHESIS,CHARACTERIZATION,THERMAL DEGRADATION AND ELECTRICAL CONDUCTIVITY OF OLIGO[2-(THIEN-2-YLMETHYLENE)AMINOPHENOL]AND OLIGOMER-METAL COMPLEXES
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作者 smet Kaya Aysel Aydin 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第4期465-477,共13页
The optimum reaction conditions of the oxidative polycondensation of 2-(thien-2-yl-methylene)aminophenol (2-TMAP) has been accomplished by using air O_2,H_2O_2 and NaOCl oxidants in an aqueous alkaline medium between... The optimum reaction conditions of the oxidative polycondensation of 2-(thien-2-yl-methylene)aminophenol (2-TMAP) has been accomplished by using air O_2,H_2O_2 and NaOCl oxidants in an aqueous alkaline medium between 20℃and 90℃.The structures of the monomer and oligomer were confirmed by FT-IR,UV-Vis,~1H-NMR and ^(13)C-NMR and elemental analysis.TGA-DTA,size exclusion chromatography(SEC) techniques and solubility tests were applied for characterization.The ~1H-NMR and ^(13)C-NMR data show that the polymeriz... 展开更多
关键词 air O_2 NAOCL O1igo[2-(thien-2-yl-methylene)aminophenol] Oxidative polycondensation Thermal analysis Electrical conductivity Oligomer-metal complex compounds
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Use of catalytic wet air oxidation (CWAO) for pretreatment of high-salinity high-organic wastewater 被引量:4
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作者 Wenjing Sun Hongxia Lv +7 位作者 Lei Ma Xiangdong Tan Chengyu Jin Huiling Wu Lili Chen Mengyang Liu Huangzhao Wei Chenglin Sun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第10期105-114,共10页
Catalytic wet air oxidation(CWAO)coupled desalination technology provides a possibility for the effective and economic degradation of high salinity and high organic wastewater.Chloride widely occurs in natural and was... Catalytic wet air oxidation(CWAO)coupled desalination technology provides a possibility for the effective and economic degradation of high salinity and high organic wastewater.Chloride widely occurs in natural and wastewaters,and its high content jeopardizes the efficacy of Advanced oxidation process(AOPs).Thus,a novel chlorine ion resistant catalyst Bsite Ru doped LaFe_(1-x)Ru_(x)O_(3-)δin CWAO treatment of chlorine ion wastewater was examined.Especially,LaFe_(0.85)Ru_(0.15)O_(3-δ)was 45.5% better than that of the 6%RuO_(2)@TiO_(2)(commercial carrier)on total organic carbon(TOC)removal.Also,doped catalysts LaFe_(1-x)Ru_(x)O_(3-)δshowed better activity than supported catalysts RuO_(2)@LaFeO_(3) and RuO_(2)@TiO_(2) with the same Ru content.Moreover,LaFe_(0.85)Ru_(0.15)O_(3-)δhas novel chlorine ion resistance no matter the concentration of Cl^(−) and no Ru dissolves after the reaction.X-ray diffraction(XRD)refinement,X-ray photoelectron spectroscopy(XPS),transmission electron microscope(TEM),and X-ray absorption fine structure(XAFS)measurements verified the structure of LaFe_(0.85)Ru_(0.15)O_(3-)δ.Kinetic data and density functional theory(DFT)proved that Fe is the site of acetic acid oxidation and adsorption of chloride ions.The existence of Fe in LaFe_(0.85)Ru_(0.15)O_(3-)δcould adsorb chlorine ion(catalytic activity inhibitor),which can protect the Ru site and other active oxygen species to exert catalytic activity.This work is essential for the development of chloride-resistant catalyst in CWAO. 展开更多
关键词 Catalytic wet air oxidation Heterogeneous catalysis LaFe_(1-x)Ru_(x)O_(3- Chlorine wastewater Salt resistance mechanism
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基于MS5534B的无人机高度传感器 被引量:6
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作者 于克振 胡延霖 周国栋 《传感技术学报》 CAS CSCD 北大核心 2006年第4期1148-1151,共4页
高度传感器是无人机的重要组成部分,具有数字输出的MS5534B很适合用于无人机高度传感器。详细介绍了传感器及接口电路和数据处理的方法,利用查表转换法实现了无人机高度传感器的功能。通过滤波算法有效地降低了采样噪声,运用Matlab对大... 高度传感器是无人机的重要组成部分,具有数字输出的MS5534B很适合用于无人机高度传感器。详细介绍了传感器及接口电路和数据处理的方法,利用查表转换法实现了无人机高度传感器的功能。通过滤波算法有效地降低了采样噪声,运用Matlab对大量的压力-高度数据进行拟合,达到了设计要求,且成功应用于某小型无人机的飞行试验。 展开更多
关键词 MS5534B压力传感器 无人机 -高转换 UAV(Unmanned air vehicle)
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齐齐哈尔地区2型糖尿病患者维生素D水平与胰岛β细胞功能的相关性研究 被引量:2
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作者 李伟 张伟 +2 位作者 潘艳慧 李雪 杨东良 《糖尿病新世界》 2018年第16期27-28,共2页
目的该文分析齐齐哈尔地区2型糖尿病患者的血清25羟维生素D[25(OH)D]同胰岛β细胞功能间的关系情况。方法选取2017年7月—2018年3月间于该院内分泌科治疗的2型糖尿病患者100例记为观察组,另选取非2型糖尿病的健康志愿者100名记为对照组... 目的该文分析齐齐哈尔地区2型糖尿病患者的血清25羟维生素D[25(OH)D]同胰岛β细胞功能间的关系情况。方法选取2017年7月—2018年3月间于该院内分泌科治疗的2型糖尿病患者100例记为观察组,另选取非2型糖尿病的健康志愿者100名记为对照组。对入组人员均行临床生化指标检查以及葡萄糖刺激后4~6 min的急性胰岛反应情况(AIR4-6)作为胰岛分泌指数指标进行分析,记录两组检查结果并进行统计学分析。结果观察组患者TC、TG、LDL-C、HDL-C水平均高于对照组,差异有统计学意义(P<0.05);观察组25(OH)D及AIR4-6均低于对照组,差异有统计学意义(P<0.05);且AIR4-6同25(OH)D、HDL-C呈正相关(P<0.05),同TC、TG、LDL-C呈负相关(P<0.05)。结论 2型糖尿病患者的25(OH)D及AIR4-6均较健康人低,且25(OH)D同胰岛β细胞间存在相关性,可以从一定程度上推测糖尿病的发生情况。 展开更多
关键词 2型糖尿病 25(OH)D 胰岛Β细胞 air4-6
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热电池加热粉中钾含量的测定
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作者 薛光荣 《电源技术》 CAS CSCD 北大核心 2005年第8期545-548,共4页
采用空气-乙炔(AIR-C2H2)火焰原子吸收光谱法对热电池加热粉中钾K的含量进行测定。介绍了K的最佳测定条件。同时对样品的处理条件和测定中的干扰因素在综合分析的基础上提出了有效的测定方案。该测定方法灵敏度好,准确度与精确度均能满... 采用空气-乙炔(AIR-C2H2)火焰原子吸收光谱法对热电池加热粉中钾K的含量进行测定。介绍了K的最佳测定条件。同时对样品的处理条件和测定中的干扰因素在综合分析的基础上提出了有效的测定方案。该测定方法灵敏度好,准确度与精确度均能满足热电池研制工作的要求。测定出的样品K含量相对标准偏差均小于1.0%(测定次数n=10)。标准加入回收率均在97%~102%(n=5)范围内。测定结果表明,运用AIR-C2H2火焰原子吸收光谱法进行热电池加热粉中K含量的测定,适用于热电池加热粉中K含量的控制。 展开更多
关键词 热电池加热粉 钾K 空气-乙炔(air—C2H2)火焰 原子吸收光谱法 分析测定
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Experimental study of temperature gradient in track slab under outdoor conditions in Chengdu area 被引量:12
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作者 Pingrui Zhao Xueyi Liu Guan Liu 《Journal of Modern Transportation》 2014年第3期148-155,共8页
Temperature is one of the important loads for designing slab track. The characteristic of slab track tem- perature varies greatly with different regional climates. In this work, a bi-block slab track model was built u... Temperature is one of the important loads for designing slab track. The characteristic of slab track tem- perature varies greatly with different regional climates. In this work, a bi-block slab track model was built under outdoor conditions in Chengdu area; the statistical characteristic of temperature gradient in track slab and the relationship between temperature gradient and surface air temperature were tested and analyzed. The results show that the track slab temperature gradient will vary periodically according to the surface air temperature, and show a clear nonlinearity along the height direction. The temperature gradient distribution is extremely uneven: the temperature gradient in the top part of the track slab is larger than that in the bottom part; the most frequently occurring temperature gradient of the track slab is around -3.5 ℃/m and more than 75 % locates in the level -10 to 10 ℃/m; concrete with a relatively good heat exchange condition with the surrounding air has a narrower band distribution. In addition, the frequency distribution histogram should exclude the time zone from 00:00 to 06:00 because there is almost no traffic in this period. The amplitude of track slab temperature variation is obviously lower than that of the air temperature variation, and the former is approximately linear with the latter. 展开更多
关键词 Slab track Track slab - Temperature gradient Temperature field Surface air temperature
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Cooling phenomena in blast furnace hearth 被引量:2
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作者 Ke-xin Jiao Jian-liang Zhang +2 位作者 Zheng-jian Liu Yong Deng Chun-lin Chen 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2018年第10期1010-1016,共7页
Cooling water provides the best protection for refractory in the blast furnace hearth. Stable and suitable water quality and abundant cooling water are the basis for long service life of the hearth. Some phenomena abo... Cooling water provides the best protection for refractory in the blast furnace hearth. Stable and suitable water quality and abundant cooling water are the basis for long service life of the hearth. Some phenomena about cooling system in the commercial blast furnaces were described, and reasonable explanations of these phenomena were analyzed. The results show that increasing the amount of cooling water and reducing the inlet temperature of cooling water can increase the cooling effect significantly in the case of water scaling. Heat flux in the blast furnace hearth is the average heat flux of cooling stave, and the erosion of carbon brick is uneven. There is no direct connection between the actual erosion condition and the heat flux in the hearth. The change trend of thermocouple temperature and heat flux in the hearth can reflect whether the gaps exist among the bricks or not, providing an effective guidance for industrial production and the evaluation of safety state in the hearth. And, the film boiling will not occur in the normal cooling system in the blast furnace hearth. 展开更多
关键词 Blast furnace hearth Cooling system Heat flux - Film boiling - Scale deposit air gap
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