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PRODUCTION OF VINYL CHLORIDE IN THE INFRARED LASER INDUCED PHOTOSENSITIZED CHAIN REACTION OF 1,2-DICHLOROETHANE

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Chinese Chemical Letters 1990年第1期1卷 29-30页

作者： Ju lin LIU pei hua MA Guan Cheng CHEN The Institute of Saline Lakes,Chinese Academy of Sciences Xining,Qinghai 810008

The chain reaction of 1,2-dichloroethane was initiated by photosensitization of SF_6 under the selective excitation using a cw CO_2 *** chloride with high purity was produced in the reaction *** initiation of the photosensitized chain reaction depends on the irradiated laser *** mechanism of intermolecular resonant transfer of vibrational energy has been discussed.

关键词： high SF PRODUCTION OF VINYL CHLORIDE IN THE INFRARED LASER INDUCED PHOTOSENSITIZED CHAIN REACTION OF 1,2-DICHLOROETHANE

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小尺度通道多孔介质表面火焰边界的实验研究

推进技术 2016年第2期37卷 311-316页

作者：林培华林宇震薛鑫张良张弛北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室北京100191

为了更好地在小尺度燃烧室中组织燃烧,对小尺度环形通道内多孔介质表面甲烷与空气预混火焰开展了流量和雷诺数边界特性实验研究。多孔介质采用了烧结金属粉末材料,燃烧在石英玻璃管和不锈钢管以及多孔介质组成的小尺度环形通道中进行。... 详细信息

为了更好地在小尺度燃烧室中组织燃烧,对小尺度环形通道内多孔介质表面甲烷与空气预混火焰开展了流量和雷诺数边界特性实验研究。多孔介质采用了烧结金属粉末材料,燃烧在石英玻璃管和不锈钢管以及多孔介质组成的小尺度环形通道中进行。研究结果表明:随着预混气流量的增加,环形通道内的火焰形态由多孔介质表面火焰向推举火焰衍变,与推举火焰相比,多孔介质表面火焰更适合于在微小型燃烧室内组织燃烧。稳态预混气温度随流量的增加先上升后下降,其流量范围与两个火焰形态的基本重合,可以将温度的转折点作为表面火焰边界的定量判据。对于多孔介质表面火焰流量边界而言,当量比小于1.0时,甲烷预混气的表面火焰流量边界随着当量比的增大逐渐变宽;当量比大于1.0时,随着当量比的增大,多孔介质表面火焰流量边界变窄。对于多孔介质表面火焰雷诺数边界而言,随着当量比的增大,雷诺数边界逐渐变宽。

关键词：小尺度燃烧多孔介质表面火焰预混燃烧环形通道实验研究

Relations of Budd-Chiari syndrome to prothrombin gene mutation

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Hepatobiliary & Pancreatic Diseases International 2004年第2期3卷 214-218页

作者： Guo-ling lin, pei-Qin Xu, hua Qi, Jian-hua Lian, Hong Zheng and Xiao-Wei Dang Zhengzhou, ChinaDepartment of General Surgery, First Affiliated Hospi- tal of Zhengzhou University the Faculty of Cytobiology and Medical Genetics, Medical School, Zhengzhou Univer- sity , Zhengzhou 450052, China Department of General Surgery First Affiliated Hospital of Zhengzhou University Zhengzhou 450052 China.

BACKGROUND: Budd-Chiari syndrome (BCS) is a type of disease characterized by portal hypertension and/or hy- pertension of the inferior vena cava (IVC) due to the ob- struction of the hepatic veins (HV) and/or intrahepatic IVC outlet. Being etiologically complicated and obscure, BCS can be acquired or idiopathic and several gene muta- tions may be contributable. This study was to explore whether prothrombin gene mutation (F G20210A) takes part in the pathogenesis of BCS and to investigate their cor- relativity. METHODS: In 38 proven BCS patients and 70 controls, polymerase chain reaction-restriction fragment length poly- morphism (PCR-RFLP) was used to find F G20210A mutation. To detect whether there are any mutations, four steps were taken: purification of genome DNA from whole blood, amplification of special fragment by polymerase chain reaction, digestion of the fragment via restriction en- donuclease, and analysis of results by polyacrylamide gel electrophoresis. RESULTS: F G20210A mutation was not detected in all patients and controls. CONCLUSIONS: No F G20210A mutation exists in Chi- nese patients with BCS, nor correlativity between the oc- currence of BCS and F G20210A mutation. The etiology of BCS in the Chinese needs further investigation.

关键词： hepatic vein thrombosis etiology F G20210A gene mutation

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多孔介质表面预混火焰熄火特性实验

航空动力学报 2014年第4期29卷 801-806页

作者：张龙许全宏张弛林培华林宇震北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室北京100191

对微型燃烧室中多孔介质表面预混火焰开展了不同孔径、孔隙率的多孔介质出口流场特性和熄火特性实验研究.研究结果表明:相对于圆管流,多孔介质出口流场边界层变薄,主流区宽度增加约50%,速度波动最大可达到前者的2.2倍.多孔介质孔径相同... 详细信息

对微型燃烧室中多孔介质表面预混火焰开展了不同孔径、孔隙率的多孔介质出口流场特性和熄火特性实验研究.研究结果表明:相对于圆管流,多孔介质出口流场边界层变薄,主流区宽度增加约50%,速度波动最大可达到前者的2.2倍.多孔介质孔径相同时,随孔隙率减小,或孔隙率相同时,随孔径减小,主流区的速度波动幅值均减小,在小孔径下更为明显,最大速度波动幅值从2.435m/s减小至1.099m/s.多孔介质表面预混火焰的熄火特性受出口流场和火焰形态的影响很大,孔隙率减小或孔径减小都会使相同当量比下熄火速度增加,多孔介质参数的影响最大可使熄火速度增加近1倍.

关键词：微型燃烧室多孔介质孔径孔隙率熄火特性

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多孔介质结构参数对表面火焰熄火特性的影响

航空动力学报 2014年第7期29卷 1654-1659页

作者：张龙许全宏张弛林培华林宇震北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室北京100191

为优化基于多孔介质头部的微型燃烧室,以甲烷/空气预混气为燃料,针对多孔介质结构参数(当量孔径、孔隙率)在不同预混气初始温度下,对表面火焰熄火特性进行实验研究.研究表明:当量孔径为120μm的多孔介质表面火焰两侧同时发生脱火,当量... 详细信息

为优化基于多孔介质头部的微型燃烧室,以甲烷/空气预混气为燃料,针对多孔介质结构参数(当量孔径、孔隙率)在不同预混气初始温度下,对表面火焰熄火特性进行实验研究.研究表明:当量孔径为120μm的多孔介质表面火焰两侧同时发生脱火,当量孔径为80μm时先发生一侧脱火.随孔隙率或当量孔径的减小,熄火速度提升.当量孔径为80μm,孔隙率为0.55,0.50,0.45的多孔介质在当量比为1.0,预混气初始温度为300K时的熄火速度分别为1.11,1.22,1.31m/s.孔隙率为0.50,孔径为120,80μm的多孔介质在当量比为1.0,预混气温度为300K时的熄火速度分别为0.73,1.22m/s.预混气初始温度的升高对当量孔径为120μm或孔隙率为0.45的多孔介质影响更加明显,预混气初始温度从300K升至500K时,熄火速度分别增加了120%,76%.

关键词：微型燃烧室多孔介质当量孔径孔隙率预混气初始温度熄火特性

限制域、预混气初始温度对多孔介质表面火焰熄火特性的影响

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航空动力学报 2014年第6期29卷 1358-1362页

作者：张龙许全宏张弛林培华林宇震北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室北京100191

为了对基于多孔介质表面火焰的微型燃烧室技术进行优化设计,以甲烷/空气预混气为研究对象,针对不同的限制域、预混气初始温度,开展了多孔介质表面火焰熄火特性实验研究.实验结果表明：在石英玻璃限制域下,多孔介质表面火焰可以维持在0.1... 详细信息

为了对基于多孔介质表面火焰的微型燃烧室技术进行优化设计,以甲烷/空气预混气为研究对象,针对不同的限制域、预混气初始温度,开展了多孔介质表面火焰熄火特性实验研究.实验结果表明：在石英玻璃限制域下,多孔介质表面火焰可以维持在0.188-0.436m/s的低预混气速度下,速度升高容易发生推举和吹熄;而限制域的长度未产生影响作用;随着预混气初始温度从293K升高至550K,多孔介质表面火焰的熄火速度极限得以提高.当量比为1.0时,预混气熄火速度从293K的1.176m/s增加至550K的2.678m/s,并存在不同斜率的上升过程,而初始温度对熄火本质没有影响.

关键词：微型燃烧室多孔介质限制域预混气初始温度熄火

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复合式收扩套筒空气雾化喷嘴燃烧室点火研究

航空动力学报 2007年第3期22卷 342-346页

作者：林宇震林培华许全宏刘高恩北京航空航天大学能源与动力工程学院航空发动机气动热力重点实验室北京100083

复合式收扩套筒空气雾化喷嘴中，副油路是一个单油路离心喷嘴，主油路采用双旋流空气雾化，喷嘴是直射式．在点火研究中，只是单油路离心喷嘴工作．实验用的燃烧室是一个单头部矩形燃烧室，在燃烧室进口温度为常温，进口压力为常压，燃... 详细信息

复合式收扩套筒空气雾化喷嘴中，副油路是一个单油路离心喷嘴，主油路采用双旋流空气雾化，喷嘴是直射式．在点火研究中，只是单油路离心喷嘴工作．实验用的燃烧室是一个单头部矩形燃烧室，在燃烧室进口温度为常温，进口压力为常压，燃烧室压力降0．9％～9．0％的试验条件下研究了复合式空气雾化喷嘴燃烧室的点火性能．在同样条件下，研究了复合式空气雾化喷嘴的雾化性能并总结了经验关系．分析了影响点火的主要因素，通过整理雾化数据，以Lefebvre点火模型为基础，总结了该类燃烧室点火经验关系．

关键词：航空航天推进系统航空发动机燃烧室点火复合式空气雾化喷嘴模型

New insight into the origin and evolution of the flora and fauna of Hainan Island, China

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Science China Earth Sciences 2025年第1期68卷 52-61页

作者： hua ZHU Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Yunnan International Joint Laboratory of Southeast Asia Biodiversity Conservation Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants

The origin of the biota of Hainan Island, China, remains a fundamental scientific problem. Comparative studies on the biota, geological tectonics, and paleomagnetism proposed that during the Eocene, Hainan Island connected Vietnam and Guangxi, and then moved to the southeast to reach its present location. This review mainly discusses its biota origin from molecular phylogeny and palaeobotanical research. The formation and evolution of the biological groups of Hainan Island were identified via research on their genomes, phylogeny, and molecular biogeography. This research showed that the genera and species that appeared and diverged early in their evolution(i.e., before the Miocene) can be explained by the land connection between Hainan Island, Vietnam, and Guangxi during the Eocene-Oligocene. According to Southeast Asian tectonic theory, in the Middle Miocene(at about 15 million years ago), Hainan Island had moved to its present position. The population and genetic divergence of species with late divergence times(after 15 Ma) can be reasonably explained by the close proximity(or land connection) between Hainan Island and the Leizhou Peninsula, enabling genetic communication between Hainan Island and the Chinese mainland, but have exceptional cases. Conclusions have been obtained through palaeobotanical studies, showing that in the Eocene-Oligocene period, southwest China and Hainan Island had subtropical vegetation and flora. However, the fossil group in southeast China(in Maoming, near present-day Hainan Island) in the Late Eocene indicated a tropical rainforest vegetation and flora. This suggests that in the Paleogene, Hainan Island may have been located near or on the southwest border of Guangxi and northern Vietnam, rather than in its present location. The floristic division of the flora of Hainan Island basically presents a northeast-southwest inclined distribution pattern. This pattern can be explained by the counterclockwise rotation of Hainan Island during i

关键词： Molecular phylogeny Biogeography Paleobotany Origin of flora and fauna Hainan Island of China

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Deciphering the role of mtH2O2 in hepatic ischemia-reperfusion injury mechanisms with low-background super-resolution fluorogenic probe

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Science China Chemistry 2025年第1期68卷 297-307页

作者： Bin Fang Limin Wang Haoqin Li Jiaxin Zhang Yang Ding Pan Pan Li Bo Peng hua Bai lin Li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University Institute of Flexible Electronics (IFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HIRI） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2O2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HIRI. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. In this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial identification to track the fluctuates of mtH2O2in HIRI. Activation of the desirable fluorescence properties of the probe by mtH2O2was confirmed using structural illumination microscopy（SIM）, enabling high-quality mitochondrial imaging with exceptional specificity and *** in mtH2O2levels were successfully observed in both cellular and rat models of HIRI. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2O2production during HIRI, which triggered mitophagy deficiency and led to cell death. In conclusion, Mito-WG possesses excellent photophysical and low-background properties for SIM imaging, making it a promising tool for mtH2O2tracking in HIRI research and clinical diagnosis.

关键词： hepatic ischemia-reperfusion injury low-background mtH2O2-activatable super-resolution imaging fluorogenic probe