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光解速率测量技术研究进展

环境科学与技术 2024年第S01期47卷 48-58页

作者：李浩然曾议朱磊窦科常振司福祺中国科学院合肥物质科学研究院安徽光学精密机械研究所环境光学与技术重点实验室安徽合肥230031 中国科学技术大学安徽合肥230026

光解反应作为大气中链式反应的引发反应,是产生二次污染物的重要原因,光解速率作为描述光解反应强度的关键参数,其数值的准确测量愈加重要。光解速率的测量技术自被研发起不断发展,截至目前常见的测量技术有化学光度计测量技术、滤波辐... 详细信息

光解反应作为大气中链式反应的引发反应,是产生二次污染物的重要原因,光解速率作为描述光解反应强度的关键参数,其数值的准确测量愈加重要。光解速率的测量技术自被研发起不断发展,截至目前常见的测量技术有化学光度计测量技术、滤波辐射计测量技术,以及光谱辐射计测量技术等。其中:化学光度计测量技术是最直接测量光解速率的方法,不过由于其操作流程烦琐、仪器复杂,多用于实验室测量;滤波辐射计测量技术是一种简化的测量技术,具有较宽的光谱覆盖,并且仪器体积小、重量轻,缺点是测量气体种类有限,测量误差较大,多用于机载测量;光谱辐射计测量技术是最通用的测量方法,能够同时测量多种气体的光解速率,并且目前已利用该原理生产出商业化的光解光谱仪,然而光谱辐射计测量技术对光谱仪要求较高,多用于外场实验。除此之外,还可以用经验公式法与脉冲(闪过或激光)光解法来获得特定情况下的光解速率。该文总结了光解速率测量技术在各方面的应用,并对可能的研究重点进行了展望。

关键词：光解反应光化通量光解速率光解光谱仪

基于MAX-DOAS观测的鹤山地区对流层甲醛廓线反演研究

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光谱学与光谱分析 2024年第6期44卷 1781-1788页

作者：钱园园罗宇涵周海金窦科常振杨太平奚亮汤付颖徐自强司福祺中国科学院合肥物质科学研究院安徽光学精密机械研究所环境光学与技术重点实验室安徽合肥230031 中国科学技术大学安徽合肥230026

甲醛(HCHO)是大气中一种十分重要的痕量气体,它不仅与人类健康和环境密切相关,还在对流层光化学反应中扮演着极其重要的角色。近年来,我国珠三角地区的秋季对流层臭氧及甲醛污染问题较为严重,而对流层甲醛也是分析边界层臭氧形成机理的... 详细信息

甲醛(HCHO)是大气中一种十分重要的痕量气体,它不仅与人类健康和环境密切相关,还在对流层光化学反应中扮演着极其重要的角色。近年来,我国珠三角地区的秋季对流层臭氧及甲醛污染问题较为严重,而对流层甲醛也是分析边界层臭氧形成机理的关键性指标之一,因此,在珠三角地区开展甲醛观测实验具有十分重要的意义。利用多轴差分吸收光谱技术(MAX-DOAS)反演了鹤山超级站2019年9月20日至10月3日期间的氧气二聚体(O_(4))与HCHO的差分斜柱浓度(DSCD),使用几何近似法得到了甲醛的大气质量因子(AMF),进而获得了对流层甲醛的垂直柱浓度(VCD)。结果显示,观测期间的对流层甲醛VCD在4.99×10^(13)~6.48×10^(16)molec·cm^(-2)之间波动,平均值为2.18×10^(16)molec·cm^(-2)。将MAX-DOAS反演的对流层甲醛VCD与TROPOMI结果进行了对比,结果表明,MAX-DOAS与TROPOMI结果近乎一致,相关性系数R为0.80,但9月25日与28日的TROPOMI结果偏低了约25%,这可能是由于观测方式不同所导致的。此外,该研究还基于反演的O_(4)与甲醛DSCD,使用基于最优估计算法的海德堡大学廓线反演算法(HEIPRO)反演了观测期间的对流层气溶胶及甲醛廓线,结果表明,甲醛污染主要集中在近地面0~800 m内,观测期间的甲醛污染主要来源于当地的工业及机动车尾气排放。将MAX-DOAS技术反演的近地面甲醛结果与2,4-二硝基苯肼色谱技术测量结果进行了对比,结果表明,两种技术的近地面甲醛结果的一致性较高,均观测到了9月27至29日的近地面甲醛高值(峰值达到了14.31μg·m^(-3)),且相关性系数R为0.88,斜率为0.98,验证了MAX-DOAS技术反演的近地面甲醛结果的可靠性。MAX-DOAS技术可实现对流层甲醛VCD的实时监测,可作为验证星载观测结果的一种重要手段,结合最优估计算法,MAX-DOAS技术还可以实现对流层甲醛廓线的反演。

关键词：多轴差分吸收光谱技术对流层甲醛最优估计算法鹤山卫星校验

基于SMPT-1000的放热反应器控制系统

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化工自动化及仪表 2024年第4期51卷 658-664,705页

作者：窦元柯邵豫生王昊原马昕北京化工大学信息科学与技术学院

反应器是具有多扰动、强耦合、非线性的流程行业生产装置,反应温度、反应速度、进料流量、进料配比等对反应产物含量均有较大影响。针对化工过程常见的连续搅拌反应器放热反应过程,遵循安全、稳定、经济的原则,根据所给工程文件进行理... 详细信息

反应器是具有多扰动、强耦合、非线性的流程行业生产装置,反应温度、反应速度、进料流量、进料配比等对反应产物含量均有较大影响。针对化工过程常见的连续搅拌反应器放热反应过程,遵循安全、稳定、经济的原则,根据所给工程文件进行理论分析和控制系统设计开发。仿真结果表明:该控制方案具有良好的控制性能。

关键词： PCS7 连续搅拌反应器放热反应

Protein kinase A-mediated cardioprotection of Tongxinluo relates to the inhibition of myocardial inflammation, apoptosis, and edema in reperfused swine hearts

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Chinese Medical Journal 2013年第8期126卷 1469-1479页

作者： LI Xiang-dong YANG Yue-jin CHENG Yu-tong dou ke-fei TIAN Yi MENG Xian-min Department of Evidence Based MedicineState key Laboratory ofCardiovascular Diseases Fuwai Hospital National Center forCardiovascular Diseases Chinese Academy of Medical Sciencesand Peking Union Medical College Beijing 100037 China Department otCardiologyState key Laboratory ofCardiovascular Diseases Fuwai Hospital National Center tbrCardiovascular Diseases Chinese Academy of Medical Sciencesand Peking Union Medical College Beijing I00037 China Experimental Animal CenterState key Laboratory ofCardiovascular Diseases Fuwai Hospital National Center tbrCardiovascular Diseases Chinese Academy of Medical Sciencesand Peking Union Medical College Beijing I00037 China Core LaboratoryState key Laboratory ofCardiovascular Diseases Fuwai Hospital National Center tbrCardiovascular Diseases Chinese Academy of Medical Sciencesand Peking Union Medical College Beijing I00037 China Department of Cardiology Beijing An Zhen Hospital CapitalMedical University Beijing 100029 China

Background Our previous studies have demonstrated that Tongxinluo （TXL）, a traditional Chinese medicine, can protect hearts against no-reflow and reperfusion injury in a protein kinase A （PKA）-dependent manner. The present study was to investigate whether the PKA-mediated cardioprotection of TXL against no-reflow and reperfusion injury relates to the inhibition of myocardial inflammation, edema, and apoptosis. Methods In a 90-minute ischemia and 3-hour reperfusion model, minipigs were randomly assigned to sham, control, TXL （0.05 g/kg, gavaged one hour prior to ischemia）, and TXL ＋ H-89 （a PKA inhibitor, intravenously and continuously infused at 1.0 μg/kg per minute） groups. Myocardial no-reflow, necrosis, edema, and apoptosis were determined by pathological and histological studies. Myocardial activity of PKA and myeloperoxidase was measured by colorimetric method. The expression of PKA, phosphorylated cAMP response element-binding protein （p-CREB）（Ser133）, tumor necrosis factor a （TNF-a）, P-selectin, apoptotic proteins, and aquaporins was detected by Western blotting analysis. Results TXL decreased the no-reflow area by 37.4% and reduced the infarct size by 27.0% （P〈0.05）. TXL pretreatment increased the PKA activity and the expression of Ser133 p-CREB in the reflow and no-reflow myocardium （P 〈0.05）. TXL inhibited the ischemia-reperfusion-induced elevation of myeloperoxidase activities and the expression of TNF-a and P-selectin, reduced myocardial edema in the left ventricle and the reflow and no-reflow areas and the expression of aquaporin-4, -8, and -9, and decreased myocytes apoptosis by regulation of apoptotic protein expression in the reflow and no-reflow myocardium. However, addition of the PKA inhibitor H-89 counteracted these beneficial effects of TXL. Conclusion PKA-mediated cardioprotection of TXL against no-reflow and reperfusion injury relates to the inhibition of myocardial inflammation, edema, and apoptosis in the reflow and no-reflow myocardium.

关键词： myocardial inlarction reperfusion therapy, Chinese herbal drugs cardioprotection

Observation of atmospheric nitrous acid with DOAS in Beijing, China

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Journal of Environmental Sciences 2006年第1期18卷 69-75页

作者： QIN Min XIE Pin-hua LIU Wen-qing LI Ang dou ke FANG Wu LIU Jian-guo ZHANG Wei-jun key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei230031 China

Measurements of nitrous acid （HONO） and nitrogen dioxide （NO2） in Beijing City have been performed by means of a developed differential optical absorption spectroscopy （DOAS） system based on photodiode array （PDA）, during the autumn of 2004. HONO and NO2 were simultaneously identified by their characteristic absorption bands in the spectral region between 337 nm and 372 nm with high sensibility and time resolution. The concentrations of HONO exhibit obviously diurnal variation with a nocturnal maximum and a daytime minimum. The highest HONO value up to 11.8 μg/m^3 was observed during the night of 2/3 September. Possible sources of the observed HONO were discussed. Good correlation to NO2 indicates that NO2 is a main source component. The measurement also shows direct emission of HONO is an imnortant source in strongly polluted urban area.

关键词： atmospheric measurements HONO NO2 DOAS source

Acute and reversible cardiomyopathy provoked by stress in a Chinese woman

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Chinese Medical Journal 2008年第23期121卷 2454-2457页

作者： KANG Lian-ming ZHANG Jian dou ke-fei XU Zhi-min GAO Xiao-jin YANG Yue-jin Department of Cardiology Cardiovascular Institute and Fuwai Hospital Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100037 China

Areversible cardiomyopathy triggered by psychologically stressful events occurs in older women and may mimic evolving acute myocardial infarction or coronary syndrome. This condition is characterized by a distinctive form of systolic dysfunction that predominantly affects the distal left ventricle chamber and a favourable outcome with appropriate medical therapy.

关键词： stress induced acute cardiomyopathy reversible cardiomyopathy

Mid-ventricular obstructive hypertrophic cardiomyopathy with apical aneurysm and sustained ventricular tachycardia： a case report and literature review

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Chinese Medical Journal 2011年第11期124卷 1754-1757页

作者： GAO Xiao-jin KANG Lian-ming ZHANG Jian dou ke-fei YUAN Jian-song YANG Yue-jin Department of Cardiology Cardiovascular Institute and FuwaiHospital Chinese Academy of Medical Sciences & Peking UnionMedical College Beijing 100037 China

The case is a 54-year-old man with hypertrophic cardiomyopathy, mid-ventricular obstruction, apical aneurysm, and recurrence sustained monomorphic ventricular tachycardia （VT）. A coronary angiogram revealed myocardial bridging located in the middle of the left anterior descending coronary artery （LAD）, and the left ventriculogram showed an hour-glass appearance of the left ventricular cavity. There was a significant pressure gradient of 60 mmHg across the mid-ventricular obliteration at rest. A successful myectomy of the inappropriate hypertrophy myocardium and excision of the apical aneurysm were performed. Pathologic analysis demonstrated fibrosis in the apical aneurysm and thickened and narrowed vessels in the adjacent area. During the follow-up of eighteen months, the patient remained clinically stable and free from arrhythmic recurrence.

关键词： hypertrophic cardiomyopathy aneurysm ventricular tachycardia

Nano-sized stationary phase packings retained by single-particle frit for microchip liquid chromatography

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Chinese Chemical Letters 2024年第4期35卷 486-489页

作者： Wangyan Hu ke Li Xiangnan dou Ning Li Xiayan Wang Center Excellence for Environmental Safety and Biological Effects Beijing Key Laboratory for Green Catalysis and SeparationDepartment of ChemistryBeijing University of TechnologyBeijing 100124China Center for Environmental Metrology National Institute of MetrologyBeijing 100029China

Modern chromatography is increasingly focused on miniaturization and integration. Compared to conventional liquid chromatography, microfluidic chip liquid chromatography(microchip-LC) has the potential due to its zero-dead volume connection and ease of integration. Nano-sized packings have the potential to significantly enhance separation performance in microchip-LC. However, their application has been hindered by packing difficulties. This study presents a method for packing nano-sized silica particles into a microchannel as the stationary phase. The microchip-LC packed column was prepared by combining the weir and the porous silica single-particle as frit to retain the packing particles. A surface tensionbased single-particle picking technique was established to insert porous single-particle frit into glass microchannels. Additionally, we developed a slurry packing method that utilizes air pressure to inject nano-sized packing into the microchannel. Pressure-driven chromatographic separation was performed using this nano-packed column integrated into a glass microchip. The mixture of four PAHs was successfully separated within just 8 min using a 5 mm separation channel length, achieving high theoretical plates(10~6plates/m). Overall, these findings demonstrate the potential of utilizing nano-sized packings for enhancing chromatographic performance in microchip systems.

关键词： Nano-size packing Single-particle frit Packed column Microchip LC Chromatographic separation

Prevention of pancreatic leakage after pancreaticoduodenectomy by modified Child pancreaticojejunostomy

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Hepatobiliary & Pancreatic Diseases International 2008年第4期7卷 426-429页

作者： Yang, Yan-Ling Xu, Xiao-Ping Wu, Guo-Qiang Yue, Shu-Qiang dou, ke-Feng Fourth Mil Med Univ Xijing Hosp Dept Hepatobiliary Surg Xian 710032 Peoples R China S Med Univ Zhujiang Hosp Dept Gen Surg Guangzhou 510282 Guangdong Peoples R China Gen Hosp Shenyang Mil Area PLA Dept Gen Surg Shenyang 110016 Peoples R China

BACKGROUND: Pancreatic leakage after pancreaticoduodenectomy is associated with a morbidity and mortality. Different techniques have been used to make a safe anastomosis to the left pancreatic remnant. METHODS: We performed 'modified Child pancreatico jejunostomy' for 31 patients, by which end-to-end pancreaticojejunal anastomosis was made with a two-layer polypropylene continuous running suture. RESULTS: In the patients who underwent pancreaticojejunostomy, the average operative time was 14.2 minutes. There was no pancreaticoenterostomy leakage in all patients, and no deaths occurred. CONCLUSIONS: In pancreaticojejunostomy, pancreatic anastomosis is time-saving and free from complications. Thus it is an improvement of pancreaticojejunostomy.

关键词： pancreaticojejunostomy pancreaticoduodenectomy pancreatic leakage