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| 1 | The Cretaceous Songliao Basin:Volcanogenic Succession,Sedimentary Sequence and Tectonic Evolution,NE China显示文摘Songliao 盆(SB ) 是有盆的二种不同类型的迭加的盆充满。更低的被一座围住差错的火山描绘包括的遗传因子的继任设置暴烈,碎屑状的焦性没食子酸和 epiclastic 岩石。暴烈的岩石,从 110 妈标明日期到 130 妈,具有 geochemically 活跃的大陆人边缘类型。快,向北方, SB 块的移植发生在从他们的 paleomagnetic 信息推断的火山作用的主要事件期间。上面盆之一充满被非海洋的下垂风格统治 siliciclastics 和次要的碳酸盐的沉积顺序。盆中心向西变了从对在盆进化建议动态变化的 GGT 地震速度结构揭示的迟了的白垩纪早。因此,一个迭加的盆模型被建议。SB 的进化包含包括的三个时期(1 ) Alptian 和 pre-Aptian:制动火箭弧盆和安第斯山脉的范围系统与蒙古鄂霍次克海 collisional 带(MOCB ) 有关打字;(2 ) Albian 到 Companian:在与沿着欧亚的板的东方边缘的和平的板的倾斜的 subduction 有关的 transtension 下面的象下垂一样罢工滑倒盆;(3 ) 自从 Maastrichtian:在与在欧亚的板下面的和平的板的正常 subduction 有关的压缩下面的构造的反的盆,由掩冲断层描绘了,向西 depocenter 的移植并且盆边缘的东方高举。 | WANG Pujun XIE Xiao'an Mattem FRANK REN Yanguang ZHU Defeng SUN Xiaomeng | 2007 | Acta Geologica Sinica(English Edition)2007，81，6： | 38 |
| 2 | Water resource utilization efficiency and spatial spillover effects in China显示文摘基于水脚印和灰色的省的面板数据浇脚印,并且在数据包封分析的帮助下当模特儿就而言并且没有考虑不受欢迎的产量,这份报纸从 1997 ~ 2011 在中国估计水资源利用效率。空间 weighting 矩阵基于经济空间的距离功能被建立讨论水资源利用效率的空间自相关。在绝对集中模型的帮助下,这份报纸断定那在那里存在在水资源利用效率的集中。在考虑并且没有考虑不受欢迎的产量的条件下面,完成集中的一半的程度分别地花大约 52.6 和 5.6 年。由空间 Durbin econometric 模型的平均数,这份报纸在中国学习省的水资源利用效率的空间溢出效果。结果如下。1 ) 与考虑并且没有考虑不受欢迎的产量,在在中国的省的水资源效率有重要空间关联。2 ) 在二个盒子下面,空间 autoregressive 系数() 分别地是 0.278 和 0.507,在 1% 意义水平。在那里存在省的水资源利用效率的空间溢出效果。3 ) 与考虑不受欢迎的产量,教育资金的这些因素,交通基础结构,和工业、农业的水消费比例有积极影响。外国直接投资的这些因素,工业增值水消费每 1 万,元,人均的水消费,和全部的降水有否定影响。4 ) 没有考虑不受欢迎的产量, GDP 的因素在水资源利用效率上每劳动者有更大的积极重要影响。然而,在 1 万元和交通基础结构的工业增值水消费的事实没有重要影响。5 ) 不管水资源利用效率的不受欢迎的输出,对在中国的现在的真实的水资源利用的评价将被弄歪,政策制定的愿望被误导。就环境因素而言的水效率措施(例如灰色的水脚印) 是更合理的。 | SUN Caizhi ZHAO Liangshi ZOU Wei ZHENG Defeng | 2014 | Journal of Geographical Sciences2014，24，5： | 29 |
| 3 | The roles of heterogeneous chemical processes in the formation of an air pollution complex and gray haze显示文摘Urban and regional air pollutions are characterized by high concentrations of secondary pollutants such as photo-oxidants (mainly ozone) and fine particulate matter,which are formed through chemical reactions of the primary pollutants emitted from various sources.The accumulation of these pollutants under stagnant meteorological conditions results in the formation of gray haze,reducing visibility and causing major impacts on human health and climate.In an air pollution complex,the coexistence of high concentrations of primary and secondary gaseous and particulate pollutants provides a large amount of reactants for heterogeneous reactions on the surface of fine particles;these reactions change the oxidizing capacity of the atmosphere,as well as chemical compositions along with the physicochemical and optical properties of particulate matter,thereby accelerating formation of the air pollution complex and gray haze.Using in situ technologies,such as diffuse reflectance infrared Fourier-transform spectroscopy and single-particle Raman spectroscopy,we systematically investigated the reaction kinetics and mechanisms of gaseous pollutants (i.e.,NO2,SO2,O3,and formaldehyde) on the surfaces of the major components of atmospheric particles such as CaCO3,kaolinite,montmorillonite,NaCl,sea salt,Al2O3,and TiO2.We found that the main reaction products were sulfate,nitrate,or formate,which can change the hygroscopicity and light extinction parameters of those particles significantly.By analyzing the reaction kinetics of these heterogeneous reactions,we identified synergetic mechanisms of the three ternary reaction systems,i.e.,NO2-particlesH2O,SO2-particles-O3,and organics/SO2-particles–UV illumination.These synergetic mechanisms can provide experimental and theoretical bases for understanding the feedback mechanisms and nonlinear processes in the formation of an air pollution complex and gray haze. | ZHU Tong,SHANG Jing & ZHAO DeFeng State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China | 2011 | Science China Chemistry2011，54，1： | 24 |
| 4 | Overexpression of microRNA-124 promotes the neuronal differentiation of bone marrow-derived mesenchymal stem cells显示文摘microRNAs(miRNAs) play an important regulatory role in the self-renewal and differentiation of stem cells. In this study, we examined the effects of miRNA-124(miR-124) overexpression in bone marrow-derived mesenchymal stem cells. In particular, we focused on the effect of overexpression on the differentiation of bone marrow-derived mesenchymal stem cells into neurons. First, we used GeneChip technology to analyze the expression of miRNAs in bone marrow-derived mesenchymal stem cells, neural stem cells and neurons. miR-124 expression was substantially reduced in bone marrow-derived mesenchymal stem cells compared with the other cell types. We constructed a lentiviral vector overexpressing miR-124 and transfected it into bone marrow-derived mesenchymal stem cells. Intracellular expression levels of the neuronal early markers β-III tubulin and microtubule-associated protein-2 were significantly increased, and apoptosis induced by oxygen and glucose deprivation was reduced in transfected cells. After miR-124-transfected bone marrow-derived mesenchymal stem cells were transplanted into the injured rat spinal cord, a large number of cells positive for the neuronal marker neurofilament-200 were observed in the transplanted region. The Basso-Beattie-Bresnahan locomotion scores showed that the motor function of the hind limb of rats with spinal cord injury was substantially improved. These results suggest that miR-124 plays an important role in the differentiation of bone marrow-derived mesenchymal stem cells into neurons. Our findings should facilitate the development of novel strategies for enhancing the therapeutic efficacy of bone marrow-derived mesenchymal stem cell transplantation for spinal cord injury. | Defeng Zou Yi Chen Yaxin Han Chen Lv Guanjun Tu | 2014 | Neural Regeneration Research2014，9，12： | 15 |
| 5 | Microbial community structure in an integrated A/O reactor treating diluted livestock wastewater during start-up period显示文摘In order to investigate the correlation between reactor performance and the microorganisms,an integrated A/O reactor was operated for 72 days to treat diluted livestock wastewater.Chemical oxygen demand (COD) removal efficiency increased from 79% to 94%,with total nitrogen (TN) removal efficiency from 37% to 50% (HRT 7.4 hr) when the influent COD and TN were ca.1500 mg/L and 95 mg/L,respectively,and the outlet COD concentration was less than 100 mg/L at the end.Microbial community was monitored during start-up period by denaturing gradient gel electrophoresis (DGGE) based on 16S rRNA gene.DGGE profiles showed that microbial community had changed significantly during the start-up and these shifts were in accordance with the reactor performance.UPGMA clustering analysis showed that 14 anaerobic samples fell into five main groups and so did the aerobic ones,but the grouping patterns were different.Phylogenetic analysis indicated that microbial populations in the anaerobic compartment belonged to Firmicutes,Proteobacteria,Chloroflexi and Bacteroidetes,while Proteobacteria,Bacteroidetes,Firmicutes,Verrucomicrobiae and Nitrospira were present in the aerobic compartment.In the anaerobic compartment,more fermentative and acetogenic bacteria were detected during the start-up while denitrifying bacteria faded away.Two functional populations such as Nitrospira defluvii and Dechloromonas denitrificans were observed when nitrogen removal was high,indicating that simultaneous nitrification and denitrification occurred in the aerobic compartment. | Lijiao Ren,Yining Wu,Nanqi Ren,Kun Zhang,Defeng Xing State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,China. | 2010 | Journal of Environmental Sciences2010，22，5： | 14 |
| 6 | Determination of Taurine in Biological Samples by High-Performance Liquid Chromatography Using 4-Fluoro-7-Nitrobenzofurazan as a Derivatizing Agent显示文摘Objective A highly sensitive and rapid high‐performance liquid chromatography method with pre‐column derivatization with 4‐fluoro‐7‐nitrobenzofurazan was developed for determination of taurine in biological samples,including plasma,brain,and liver.Methods The optimum derivatization reaction temperature was 70℃,and at this temperature the reaction was complete within 3 min.The derivatized taurine was separated using phosphate buffer (0.02 mol/L,pH 6.0):acetonitrile (84:16,v/v) as the mobile phase at a flow rate of 1.0 mL/min,and a column temperature of 25℃.The taurine derivatives were separated within 20 min (tR:14.5 min) and fluorometrically detected at 530 nm with excitation at 470 nm.Results The intra‐ and the inter‐day coefficients of variation for the method were 5.3% and 7.7%,respectively.The calibration curve was linear from 0.1 μmol/L to 30.0 μmol/L with a correlation coefficient of 0.9995.Conclusion This method can be used to determine the taurine contents in plasma,brain,and liver from normal rats and human plasma. | WANG XiFeng CHI DeFeng SU GuanMin LI Lin SHAO LiHua | 2011 | Biomedical and Environmental Sciences2011，24，5： | 13 |
| 7 | Research Progress on Heat Stress of Rice at Flowering Stage显示文摘Global warming has caused frequent occurrence of heat stress at the flowering stage of single-season rice in the Yangtze River region of China, which results in declines of spikelet fertility and yield in rice. Rice flowering stage is the most sensitive period to high temperatures, and therefore, the key for heat stress happening is the flowering stage coinciding with high temperature, which causes spikelet fertility decreasing in heat-sensitive varieties, and is the major factor for heat injury differences among various rice planting regions. With the development of rice breeding, temperature indexes for heat stress has been converted from daily maximum temperature of 35 oC to 38 oC with the stress duration of more than 3 d. During the flowering stage, anther dehiscence inhibition and low pollen shedding onto the stigma are two main reasons for spikelet fertility reduction under high temperatures. At panicle initiation stage, high temperatures aggravate spikelet degeneration, and destroy floral organ development. Various types of rice varieties coexist in production, and indica-japonica hybrid rice demonstrates the highest heat resistance in general, followed by indica and japonica rice varieties. In production, avoiding high temperature is the main strategy of preventing heat stress, and planting suitable cultivars and adjustment of sowing date are the most effective measures. Irrigation is an effective real-time cultivation measure to decline the canopy temperature during the rice flowering stage. We suggested that further study should be focused on exploring heat injury differences among different rice variety types, and innovating rice-planting methods according to planting system changes in rice planting regions with extreme heat stress. Meanwhile, high temperature monitor and warning systems should be improved to achieve optimal heat stress management efficiencies. | WANG Yaliang WANG Lei ZHOU Jianxia HU Shengbo CHEN Huizhe XIANG Jing ZHANG Yikai ZENG Yongjun SHI Qinghua ZHU Defeng ZHANG Yuping | 2019 | Rice science2019，26，1： | 13 |
| 8 | Empirical Research on Carrying Capacity of Human Settlement System in Dalian City, Liaoning Province, China显示文摘Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationship among the factors such as regional population, resources, environment and economic and social development in the context of China′s rapid urbanization. Then the concept and characterization methods of the regional human settlement carrying capacity were proposed by means of population scale. Furthermore, a model of carrying capacity-pressure-state-response(CPSR) on regional human settlement system was established by referencing pressure-state-response(PSR) model, and the Catastrophe Theory was introduced to determine the corresponding standards of multi-criteria programming and evaluation. Taking Dalian City, Liaoning Province, China as an example, an empirical analysis on evaluation of human settlement system from 2000 to 2012 was carried out. The results showed that the carrying capacity of human settlement system in Dalian was fluctuating between 9.6 × 106 to 10 × 106 persons with a quantitative stage of the dynamic regulation. During the research period the load index of human settlement system in Dalian dropped from 0.96 to 0.84 with a lower pressure of human settlement system than the national average level. And the emergency response grades of human settlement system in Dalian were kept in grade Ⅱ(orange warning) or grade Ⅲ(yellow warning). Human settlement system of Dalian was in slight security state as a whole, but the load had a tendency of increase in recent years. The related departments should pay close attention to regional human settlement system and take active measures to improve human settlement by both intensity control and total quantity control. By comparison, analysis and discussion, it was considered that the results were basically accordded with the current situations of human settlement in Dalian, and the evaluation results were more reliable, visualized and easily applied in practice. Therefore, the above-mentioned concepts, characterization and evaluation methods of the regional human settlement system and carrying capacity could provide a new thought and method for quantitative evaluation of human settlement. | ZHENG Defeng ZHANG Yu ZANG Zheng SUN Caizhi | 2015 | Chinese Geographical Science2015，25，2： | 13 |
| 9 | Spaceborne GPS receiver antenna phase center offset and variation estimation for the Shiyan 3 satellite显示文摘In determining the orbits of low Earth orbit(LEO) satellites using spaceborne GPS, the errors caused by receiver antenna phase center offset(PCO) and phase center variations(PCVs) are gradually becoming a major limiting factor for continued improvements to accuracy. Shiyan 3, a small satellite mission for space technology experimentation and climate exploration, was developed by China and launched on November 5, 2008. The dual-frequency GPS receiver payload delivers1 Hz data and provides the basis for precise orbit determination within the range of a few centimeters. The antenna PCO and PCV error characteristics and the principles influencing orbit determination are analyzed. The feasibility of PCO and PCV estimation and compensation in different directions is demonstrated through simulation and in-flight tests. The values of receiver antenna PCO and PCVs for Gravity Recovery and Climate Experiment(GRACE) and Shiyan 3 satellites are estimated from one month of data. A large and stable antenna PCO error, reaching up to10.34 cm in the z-direction, is found with the Shiyan 3 satellite. The PCVs on the Shiyan 3 satellite are estimated and reach up to 3.0 cm, which is slightly larger than that of GRACE satellites. Orbit validation clearly improved with independent k-band ranging(KBR) and satellite laser ranging(SLR) measurements. For GRACE satellites, the average root mean square(RMS) of KBR residuals improved from 1.01 cm to 0.88 cm. For the Shiyan 3 satellite, the average RMS of SLR residuals improved from 4.95 cm to 4.06 cm. | Gu Defeng Lai Yuwang Liu Junhong Ju Bing Tu Jia | 2016 | Chinese Journal of Aeronautics2016，29，5： | 11 |
| 10 | Basic performance of BeiDou-2 navigation satellite system used in LEO satellites precise orbit determination显示文摘The visibility for low earth orbit(LEO) satellites provided by the BeiDou-2 system is analyzed and compared with the global positioning system(GPS). In addition, the spaceborne receivers' observations are simulated by the BeiDou satellites broadcast ephemeris and LEO satellites orbits. The precise orbit determination(POD) results show that the along-track component accuracy is much better over the service area than the non-service area, while the accuracy of the other two directions keeps at the same level over different areas. However, the 3-dimensional(3D) accuracy over the two areas shows almost no difference. Only taking into consideration the observation noise and navigation satellite ephemeris errors, the 3D accuracy of the POD is about30 cm. As for the precise relative orbit determination(PROD), the 3D accuracy is much better over the eastern hemisphere than that of the western hemisphere. The baseline length accuracy is 3.4 mm over the service area, and it is still better than 1 cm over the non-service area. This paper demonstrates that the BeiDou regional constellation could provide global service to LEO satellites for the POD and the PROD. Finally, the benefit of geostationary earth orbit(GEO) satellites is illustrated for POD. | Liu Junhong Gu Defeng Ju Bing Yao Jing Duan Xiaojun Yi Dongyun | 2014 | Chinese Journal of Aeronautics2014，27，5： | 9 |
| 11 | Precession–nutation correction for star tracker attitude measurement of STECE satellite显示文摘Space Technology Experiment and Climate Exploration(STECE) is a small satellite mission of China for space technology experiment and climate exploration. A new test star tracker and one ASTRO 10 star tracker have been loaded on the STECE satellite to test the new star tracker's measurement performance. However,there is no autonomous precession–nutation correction function for the test star tracker,which causes an apparent periodic deflection in the inter-boresight angle between the two star trackers with respect to each other of up to ±500 arcsec,so the precession and nutation effect needs to be considered while assessing the test star tracker. This paper researches on the precession–nutation correction for the test star tracker's attitude measurement and presents a precession–nutation correction method based on attitude quaternion data. The periodic deflection of the inter-boresight angle between the two star trackers has been greatly eliminated after the precession and nutation of the test star tracker's attitude data have been corrected by the proposed method and the validity of the proposed algorithm has been demonstrated. The in-flight accuracy of the test star tracker has been assessed like attitude noise and low-frequency errors after the precession–nutation correction. | Lai Yuwang Liu Junhong Ding Yonghe Gu Defeng Yi Dongyun | 2014 | Chinese Journal of Aeronautics2014，27，1： | 7 |
| 12 | Integrating BDS and GPS for precise relative orbit determination of LEO formation flying显示文摘Low-Earth-Orbit(LEO) formation-flying satellites have been widely applied in many kinds of space geodesy. Precise Relative Orbit Determination(PROD) is an essential prerequisite for the LEO formation-flying satellites to complete their mission in space. The contribution of the BeiDou Navigation Satellite System(BDS) to the accuracy and reliability of PROD of LEO formation-flying satellites based on a Global Positioning System(GPS) is studied using a simulation method. Firstly, when BDS is added to GPS, the mean number of visible satellites increases from9.71 to 21.58. Secondly, the results show that the 3-Dimensional(3 D) accuracy of PROD, based on BDS-only, GPS-only and BDS + GPS, is 0.74 mm, 0.66 mm and 0.52 mm, respectively. When BDS co-works with GPS, the accuracy increases by 29.73%. Geostationary-Earth-Orbit(GEO) satellites and Inclined Geosynchronous-Orbit(IGSO) satellites are only distributed over the Asia-Pacific region; however, they could provide a global improvement to PROD. The difference in PROD results between the Asia-Pacific region and the non-Asia-Pacific region is not apparent. Furthermore, the value of the Ambiguity Dilution Of Precision(ADOP), based on BDS + GPS, decreases by 7.50% and 8.26%, respectively, compared with BDS-only and GPS-only. Finally, if the relative position between satellites is only a few kilometres, the effect of ephemeris errors on PROD could be ignored. However, for a several-hundred-kilometre separation of the LEO satellites, the SingleDifference(SD) ephemeris errors of GEO satellites would be on the order of centimetres. The experimental results show that when IGSO satellites and Medium-Earth-Orbit(MEO) satellites co-work with GEO satellites, the accuracy decreases by 17.02%. | Bin YI Defeng GU Xiao CHANG Kai SHAO | 2018 | Chinese Journal of Aeronautics2018，31，10： | 7 |
| 13 | Root morphology in response to nitrogen supply in mid-season indica rice cultivars released in different decades显示文摘Dear Editor,Roots,as a major organ of plants,are involved in nutrient and water acquisition,and might play a vital role in yield increase and efficient N absorption with genetic improvement.Because of the great differences in growth period and pattern between the old and new rice cultivars,it is difficult to clarify how genetic improvements contribute to root growth in rice.For example,for a solution culture system,Wu et al.suggested that total root length increased with increasing year of release for maize hybrids,while shoot dry weight, | Yikai Zhang Huizhe Chen Yuping Zhang Jing Xiang Guangmei Ji Defeng Zhu | 2017 | Science China(Life Sciences)2017，60，4： | 7 |
| 14 | Decrement of Sugar Consumption in Rice Young Panicle Under High Temperature Aggravates Spikelet Number Reduction显示文摘Two rice genotypes Huanghuazhan(HHZ, heat-resistant) and IR36(heat-susceptible) were subjected to high-temperature(HT, 40℃) and normal-temperature(NT, 32℃) treatments at the spikelet differentiation stage. HT treatment inhibited spikelet differentiation, aggravated spikelet degeneration, reduced spikelet size, and disordered carbohydrate allocation. Meanwhile, HT treatment increased nonstructural carbohydrate content in leaves, but decreased that in stems and young panicles, and the same tendencies of sucrose and starch contents were observed in leaves and stem. However, HT treatment significantly increased the sucrose content and sharply decreased the glucose and fructose contents in young panicles. Lower activity levels of soluble acid invertase(EC3.2.1.26) and sucrose synthase(EC2.4.1.13) were observed under HT treatment. Moreover, HT treatment reduced the activities of key enzymes associated with glycolysis and the tricarboxylic acid cycle, which indicated sucrose consumption was inhibited in young panicles under HT treatment. Exogenous glucose and fructose applied under HT treatment increased the spikelet number more than exogenous sucrose. In conclusion, the results demonstrated that the reduction of spikelet number under high temperature was more affected by the decrease in sugar consumption than the blocking of sucrose transport. The impairment of sucrose hydrolysis was the main reason for the inhibition of sugar utilization. | WANG Yaliang ZHANG Yikai SHI Qinghua CHEN Huizhe XIANG Jing HU Guohui CHEN Yanhua WANG Xiaodan WANG Junke YI Zihao ZHU Defeng ZHANG Yuping | 2020 | Rice science2020，27，1： | 6 |
| 15 | Atomic Fe-Zn dual-metal sites for high-efficiency pH-universal oxygen reduction catalysis显示文摘An effective electrocatalyst being highly active in all pH range for oxygen reduction reaction(ORR)is crucial for energy conversion and storage devices.However,most of the high-efficiency ORR catalysis was reported in alkaline conditions.Herein,we demonstrated the preparation of atomically dispersed Fe-Zn pairs anchored on porous N-doped carbon frameworks(Fe-Zn-SA/NC),which works efficiently as ORR catalyst in the whole pH range.It achieves high half-wave potentials of 0.78,0.85 and 0.72 V in 0.1 M HClO4,0.1 M KOH and 0.1 M phosphate buffer saline(PBS)solutions,respectively,as well as respectable stability.The performances are even comparable to Pt/C.Furthermore,when assembled into a Zn-air battery,the high power density of 167.2 mWcm−2 and 120 h durability reveal the feasibility of Fe-Zn-SA/NC in real energy-related devices.Theoretical calculations demonstrate that the superior catalytic activity of Fe-Zn-SA/NC can be contributed to the lower energy barriers of ORR at the Fe-Zn-N6 centers.This work demonstrates the potential of Fe-Zn pairs as alternatives to the Pt catalysts for efficient catalytic ORR and provides new insights of dual-atom catalysts for other energy conversion related catalytic reactions. | Jie Xu Shuhua Lai Defeng Qi Min Hu Xianyun Peng Yifan Liu Wei Liu Guangzhi Hu Heng Xu Fan Li Chao Li Jia He Longchao Zhuo Jiaqiang Sun Yuan Qiu Shusheng Zhang Jun Luo Xijun Liu | 2021 | Nano Research2021，14，5： | 6 |
| 16 | Monitoring of microbial community structure and succession in the biohydrogen production reactor by denaturing gradient gel electrophoresis(DGGE)显示文摘To study the structure of microbial communities in the biological hydrogen produc- tion reactor and determine the ecological function of hydrogen producing bacteria, anaerobic sludge was obtained from the continuous stirred tank reactor (CSTR) in different periods of time, and the diversity and dynamics of microbial communities were investigated by denaturing gra- dient gel electrophoresis (DGGE). The results of DGGE demonstrated that an obvious shift of microbial population happened from the beginning of star-up to the 28th day, and the ethanol type fermentation was established. After 28 days the structure of microbial community became stable, and the climax community was formed. Comparative analysis of 16S rDNA sequences from reamplifying and sequencing the prominent bands indicated that the dominant population belonged to low G+C Gram-positive bacteria (Clostridium sp. and Ethanologenbacterium sp.), β- proteobacteria (Acidovorax sp.), γ-proteobacteria (Kluyvera sp.), Bacteroides (uncultured bacte- rium SJA-168), and Spirochaetes (uncultured eubacterium E1-K13), respectively. The hydrogen production rate increased obviously with the increase of Ethanologenbacterium sp., Clostridium sp. and uncultured Spirochaetes after 21 days, meanwhile the succession of ethanol type fer- mentation was formed. Throughout the succession the microbial diversity increased however it decreased after 21 days. Some types of Clostridium sp. Acidovorax sp., Kluyvera sp., and Bac- teroides were dominant populations during all periods of time. These special populations were essential for the construction of climax community. Hydrogen production efficiency was de- pendent on both hydrogen producing bacteria and other populations. It implied that the co- metabolism of microbial community played a great role of biohydrogen production in the reactors. | XING Defeng REN Nanqi GONG Manli LI Jianzheng LI Qiubo | 2005 | Science China(Life Sciences)2005，48，2： | 5 |
| 17 | A preliminary analysis of the surface chemistry of atmospheric aerosol particles in a typical urban area of Beijing显示文摘Atmospheric aerosol particle samples were collected using an Ambient Eight Stage(Non-Viable) Cascade Impactor Sampler in a typical urban area of Beijing from 27 th Sep.to 5th Oct.,2009.The surface chemistry of these aerosol particles was analyzed using Static Time of Flight-Secondary Ion Mass Spectrometry(Static TOF-SIMS).The factors influencing surface compositions were evaluated in conjunction with the air pollution levels,meteorological factors,and air mass transport for the sampling period.The results show that a variety of organic ion groups and inorganic ions/ion groups were accumulated on the surfaces of aerosol particles in urban areas of Beijing;and hydrophobic organic compounds with short-or middle-chain alkyl as well as hydrophilic secondary inorganic compounds were observed.All these compounds have the potential to affect the atmospheric behavior of urban aerosol particles.PM1.1–2.1and PM3.3–4.7had similar elements on their surfaces,but some molecules and ionic groups demonstrated differences in Time of Flight-Secondary Ion Mass Spectrometry spectra.This suggests that the quantities of elements varied between PM1.1–2.1and PM3.3–4.7.In particular,more intense research efforts into fluoride pollution are required,because the fluorides on aerosol surfaces have the potential to harm human health.The levels of air pollution had the most significant influence on the surface compositions of aerosol particles in our study.Hence,heavier air pollution was associated with more complex surface compositions on aerosol particles.In addition,wind,rainfall,and air masses from the south also greatly influenced the surface compositions of these urban aerosol particles. | Zhengzheng Zhang Hong Li Hongyan Liu Runxiang Ni Jinjuan Li Liqun Deng Defeng Lu Xueli Cheng Pengli Duan Wenjun Li | 2016 | Journal of Environmental Sciences2016，28，9： | 5 |
| 18 | Role of oxidative stress in alcohol-induced liver injury显示文摘 | Arthur I. Cederbaum Yongke Lu Defeng Wu | 2009 | Archives of Toxicology2009，，6： | 5 |
| 19 | Raman micro-spectrometry as a technique for investigating heterogeneous reactions on individual atmospheric particles显示文摘Investigating the heterogeneous reaction on individual atmospheric particles is important because it approximates actual atmospheric conditions and can aid in reducing artifacts in elucidating real mechanisms and processes,and determining real kinetic parameters of the atmosphere relevance.This study developed a Raman microspectrometry method to investigate heterogeneous reactions on individual particles.The method was applied to the reaction of NO2 with individual CaCO3 particles.It was demonstrated that Raman microspectrometry can obtain information on both chemical composition and microscopic morphology at the same time,as well as information on chemical characteristics,such as the phase,which is useful for studying reaction processes.Raman spectra of individual particles deposited on a substrate showed no interference by morphological resonance,which is helpful for obtaining high-quality spectra.Moreover,Raman microspectrometry was compared with other methods for investigating heterogeneous reactions on individual particles and was found to have several advantageous characteristics. | ZHAO DeFeng,ZHU Tong,CHEN Qi,LIU YingJun & ZHANG ZeFeng State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China | 2011 | Science China Chemistry2011，54，1： | 5 |
| 20 | Phase Residual Estimations for PCVs of Spaceborne GPS Receiver Antenna and Their Impacts on Precise Orbit Determination of GRACE Satellites显示文摘In-flight phase center systematic errors of global positioning system(GPS) receiver antenna are the main restriction for improving the precision of precise orbit determination using dual-frequency GPS.Residual approach is one of the valid methods for in-flight calibration of GPS receiver antenna phase center variations(PCVs) from ground calibration.In this paper,followed by the correction model of spaceborne GPS receiver antenna phase center,ionosphere-free PCVs can be directly estimated by ionosphere-free carrier phase post-fit residuals of reduced dynamic orbit determination.By the data processing of gravity recovery and climate experiment(GRACE) satellites,the following conclusions are drawn.Firstly,the distributions of ionosphere-free carrier phase post-fit residuals from different periods have the similar systematic characteristics.Secondly,simulations show that the influence of phase residual estimations for ionosphere-free PCVs on orbit determination can reach the centimeter level.Finally,it is shown by in-flight data processing that phase residual estimations of current period could not only be used for the calibration for GPS receiver antenna phase center of foretime and current period,but also be used for the forecast of ionosphere-free PCVs in future period,and the accuracy of orbit determination can be well improved. | TU Jia GU Defeng WU Yi YI Dongyun | 2012 | Chinese Journal of Aeronautics2012，25，4： | 4 |
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