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活性炭管采集气相色谱测定空气中邻-氯甲苯的实验研究

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环境与职业医学 2005年第5期22卷 464-466页

作者：史马喜张鸣徐以盛朱音音上海市闸北区疾病预防控制中心上海200070 上海市疾病预防控制中心上海200336

[目的]研究炭管采集空气中邻-氯甲苯的气相色谱分析方法。[方法]活性炭吸附空气中邻-氯甲苯,样品经溶剂解吸,色谱检测。[结果]当空气中邻-氯甲苯的浓度范围在31.83-2 037 mg/m3(参照美国标准259 mg/m3)时, 方法的变异系数为1.2%～4.9%;... 详细信息

[目的]研究炭管采集空气中邻-氯甲苯的气相色谱分析方法。[方法]活性炭吸附空气中邻-氯甲苯,样品经溶剂解吸,色谱检测。[结果]当空气中邻-氯甲苯的浓度范围在31.83-2 037 mg/m3(参照美国标准259 mg/m3)时, 方法的变异系数为1.2%～4.9%;回归方程式Y=3 399+135.0X,相关系数r=0.999 9。方法检出限2.3μg/ml。平均解吸效率为93.5%,穿透容量(BTV)为9.05 mg。活性炭吸附111.8μg的邻-氯甲苯,样品放置2周,回收率仍可达91.9%。本法的测定范围上限取决于炭管的吸附量,而该吸附量可随空气中邻-氯甲苯的浓度及其他物质而变化。[结论]本方法可应用于车间环境中邻-氯甲苯浓度的测定(改变色谱操作条件还可测定多种样品)。

关键词：邻-氯甲苯炭管溶剂解吸稳定性穿透容量气相色谱

结合催化气化过程的高效直接碳固体氧化物燃料电池(英文)

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催化学报 2015年第4期36卷 509-516页

作者： M.Konsolakis g.E.Marnellos A.Al-Musa N.Kaklidis I.garagounis V.Kyriakou School of Production Engineering and Management Technical University of Crete GR-73100 Chania Crete Greece Department of Mechanical Engineering University of Western Macedonia GR-50100 Kozani Greece Chemical Process & Energy Resources Institute CERTH GR-57001 Thermi Thessaloniki Greece National Center for Combustion and Plasma Technologies Water and Energy Research Institute King Abdulaziz City for Science and Technology (KACST)P.O.Box 6086 11442 Riyadh Saudi Arabia Department of Chemical Engineering Aristotle University of Thessaloniki GR-54124 Thessaloniki Greece

This study explores strategies to develop highly efficient direct carbon fuel cells(DCFCs) by com-bining a solid-oxide fuel cell(SOFC) with a catalyst-aided carbon-gasification process. This system employs Cu/CeO 2 composites as both anodic electrodes and carbon additives in a cell of the type: carbon|Cu-CeO 2/YSZ/Ag|air. The study investigates the impact on in situ carbon-gasification and DCFC performance characteristics of catalyst addition and variation in the carrier gas used(inert He versus reactive CO2). The results indicate that cell performance is significantly improved by infusing the catalyst into the carbon feedstock and by employing CO2 as the carrier gas. At 800 ℃, the maxi.mum power output is enhanced by approximately 40% and 230% for carbon/CO2 and car-bon/catalyst/CO2 systems, respectively, compared with that of the carbon/He configuration. The increase observed when employing the catalyst and CO2 as the carrier gas can be primarily at-tributed to the pronounced effect of the catalyst on carbon-gasification through the re-verse-Boudouard reaction, and the subsequent in situ electro-oxidation of CO at the anode three-phase boundary.

关键词：固体氧化物燃料电池二氧化碳气化过程催化剂电力电池性能 CO2 SOFC

世界级职业自行车运动员的左室连续性适应:疾病筛查及随访的意义

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世界核心医学期刊文摘（心脏病学分册） 2005年第2期1卷 52-53页

作者： Abergel E. Chatellier g. Hagege A.A. 刘豫 Service de Cardiologie Paris France Dr.

Objectives The purpose of this research was to study long term left ventricul ar(LV) adaptations in very high level endurance athletes. Background Knowledge of cardiac changes in athletes, who are at particularly high risk of sudden car diac death, is mandatory to detect hypertrophic cardiomyopathy (HCM) or dilated (DCM) cardiomyopathy. Methods We carried out echocardiographic examinations on 2 86 cyclists(group A) and 52 matched sedentary volunteers (group C); 148 cyclists participated in the 1995 “Tour de France”race (group A1), 138 in the 1998 rac e (group A2), and 37 in both (group B). Results In groups A, A1, A2, and C, resp ectively, diastolic left ventricular diameter (LVID)was 60.1±3.9 mm, 59.2±3.8 mm, 61.0±3.9 mm, and 49.0 ±4.3 mm (A vs. C and A1 vs. A2, pmaxi.mal wall thickness (WT) was 11.1 ±1.3 mm, 11.6 ±1.3 mm, 10.6 ±1.1 mm, and 8.6 ±1.0 mm (A vs. C and A1 vs. A2, pg group A, 147 (51.4%) had LV ID >60 mm; 17 of them had also a below normal (55 mm. In group B, LVID increased (58.3 ±4.8 mm to 60.3 ±4.2 mm, pg with a reduced LVEF in 11.6%(17 of 147), compatible with the diagn osis of DCM. Increased WT was less common (always g the diagnosis of HCM. Serial examinations showed evidence of furth er LV dilation along with wall thinning. These results might have important impl ications for screening in athletes.

关键词：疾病筛查自行车运动员运动员心脏自行车赛肥厚型心肌病扩张型心肌病心脏超声检查室壁厚度左室舒张末统计学显著性

Spectral and Timing Analysis of the Black Hole Transient maxi.J1631–479 During its 2019 Outburst Observed with Insight-HXMT

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Research in Astronomy and Astrophysics 2022年第11期22卷 21-33页

作者： Yu-Cong Fu L.M.Song g.Q.Ding S.N.Zhang J.L.Qu S.Zhang L.Zhang Q.C.Bu Y.Huang X.Ma Z.X.Yang Y.L.Tuo X.F.Lu D.K.Zhou B.Y.Wu T.M.Li Y.C.Xu Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqiXinjiang 830011China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Institut fur Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard Karls UniversitatSand 1D-72076 TübingenGermany

We report spectral and timing analysis of the black hole transient maxi.J1631–479 during the hard intermediate state of its 2019 outburst from the Insight-Hard X-ray Modulation Telescope(Insight-HXMT)*** find that the energy dependence of the type-C quasi-periodic oscillation(QPO)frequency evolves with time:during the initial rise of a small flare(~MJD 58526.0-58527.1),the QPO frequency increases with increasing energy from~1 to~100 ke V,and then the frequency remains constant after MJD *** discover a possible new phenomenon of Fe line’s QPO frequency jump that has never been observed for other black hole transients:during the small flare,the QPO frequency around the Fe line energy is higher than any other energy band,with the frequency difference Δf=0.25±0.08 Hz between 5.5–7.5 ke V and other energy *** spectral analysis shows that the evolution of QPOs is related to the equivalent width of the narrow Fe line,and its equivalent width increases during this small *** propose that the QPO frequency difference results from the differential precession of a vertically extended jet,and the higher QPO frequency of Fe line could be caused by the layered jet when the jet scale *** the same time,the evolution of QPOs is related to the accretion rate,while the energy dependence of QPOs supports the existence of deceleration in the vertically distributed jet.

关键词： accretion accretion disks stars:black holes X-rays:binaries