维普中文期刊产品整合服务
61篇 您的检索式:作者名="Defeng Zhang"
    题名 作者 年代 出处 被引量
1Microbial 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. 2010Journal of Environmental Sciences2010,22,5:14
2Research 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 2019Rice science2019,26,1:13
3Empirical 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 2015Chinese Geographical Science2015,25,2:13
4Root 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 2017Science China(Life Sciences)2017,60,4:7
5Decrement 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 2020Rice science2020,27,1:6
6Atomic 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 2021Nano Research2021,14,5:6
7A 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 2016Journal of Environmental Sciences2016,28,9:5
8Raman 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 2011Science China Chemistry2011,54,1:5
9Age assignment and geological significance of the “Budate Group” in the Hailar Basin显示文摘Age and nature of the Budate Group in the Hailar Basin are of great significance in studying the evolution of the Hailar Basin and the Xing'an-Mongolian Orogenic Belt(XMOB).Zircon U-Pb ages of eight volcanic rocks from the Budate Group and two basement granites in the Hailar Basin were reported in this study.The dating results indicated that the formation of these volcanic rocks was consistent with the emplacement of Late Paleozoic basement granite in age(356-290 Ma),i.e.,Early Carboniferous to Early Permian rather than Early Mesozoic.Combined with regional geology,it was concluded that the Budate Group is the component of the basement of the Hailar Basin,and these volcanic rocks were formed at an active continental margin,which is related to the closure of the Hegen Mountains suture zone.The captured Neoproterozoic zircons(814-873 Ma) were probably derived from the Neoproterozoic basement materials in the Ergun Block,implying the close genetic relationships between the Ergun Block(including the Hailar Basin) and the Siberian Block.MENG Qi'An WAN ChuanBiao ZHU DeFeng ZHANG YanLong GE WenChun WU FuYuan 2013Science China Earth Sciences2013,56,6:4
10The structural characteristics, age of origin, and tectonic attribute of the Erguna Fault, NE China显示文摘The Erguna Fault runs along the east bank of the Erguna River in NE China and is a large-scale ductile shear zone comprising granitic mylonites. This paper reports on the geometry, kinematic indicators, and 40Ar/39 Ar biotite ages of the granitic mylonites, to constrain the structural characteristics, forming age, and tectonic attribute of the Erguna ductile shear zone. The zone strikes NE and records a top-to-the-NW sense of shear. A mylonitic foliation and stretching lineation are well developed in the mylonites, which are classified as S-L tectonites. Logarithmic flinn parameters(1.18–2.35) indicate elongate strain which approximates to plane strain. Kinematic vorticity numbers are 0.42–0.92 and 0.48–0.94, based on the polar Mohr diagram and the oblique foliation in quartz ribbons, respectively, suggesting that the ductile shear zone formed under general shear, or a combination of simple and pure shear. According to finite strain and kinematic vorticity analyses, the Erguna Fault is a lengthening-thinning ductile shear zone that formed by extension. The deformation behavior of minerals in the mylonites indicates that the fault was the site of three stages of deformation: an initial stage of middle- to deep-level, high-temperature shear, a post-stress recovery phase of high-temperature static recrystallization, and a final phase of low-temperature uplift and cooling. The 40Ar/39 Ar plateau ages of biotite from the granitic mylonites are 106.16 ± 0.79 and 111.55 ± 0.67 Ma, which constrain the timing of low-temperature uplift and cooling but are younger than the ages of metamorphic core complexes(MCCs) in the Transbaikalia-northeast Mongolia region. Using measured geological sections, microtectonics, estimates of finite strain and kinematic vorticity, and regional correlations and geochronology, we conclude that the Erguna Fault is an Early Cretaceous, NNE-trending, large-scale, sub-horizontal, and extensional ductile shear zone. It shares a similar tectonic background with the MCCs, volcanic fault basins, and large and super-large volcanic-hydrothermal deposits in Transbaikalia-northeast Mongolia and the western Great Khingan Mountains, all of which are the result of overthickened crust that gravitationally collapsed and extended in the Early Cretaceous after plate collision along the present-day Sino-Russia-Mongolia border tract.ZHENG Han SUN XiaoMeng ZHU DeFeng TIAN JingXiong HE Song WANG YingDe ZHANG XuQing 2015Science China Earth Sciences2015,58,9:3
11TOF–SIMS surface analysis of chemical components of size–fractioned urban aerosols in a typical heavy air pollution event in Beijing显示文摘Size–fractioned atmospheric aerosol particles were collected during a typical heavy air pollution event in Beijing. The organic and inorganic components on the surfaces of the samples were analyzed using time–of–flight secondary ion mass spectrometry(TOF–SIMS).The variation characteristics of the surface chemical composition and influencing factors were studied, and the possible sources of these chemical compositions were identified through principal component analysis. The results showed that inorganic components such as crustal elements and sulfate, and organic components such as aliphatic hydrocarbons and oxygen–containing organic groups were present. Some surface components, such as polycyclic aromatic hydrocarbons, heavy metals and fluorides may exert adverse effects on human health. The species and relative percentages of the chemical components varied with particle size, diurnal and pollution progress. During a heavy pollution event, the species and relative percentages of secondary components such as oxygen–containing organic groups and sulfurous compounds increased, indicating that particles aged during this event. The surface chemical composition of the aerosol particles was affected mainly by emissions from coal combustion and motor vehicles. In addition, air pollution, meteorological factors, and air mass transport also exerted a significant effect on the surface chemical composition of aerosol particles.Wenjun Li Hong Li Jinjuan Li Xueli Cheng Zhengzheng Zhang Fahe Chai Hao Zhang Ting Yang Pengli Duan Defeng Lu Yizhen Chen 2018Journal of Environmental Sciences2018,30,7:2
12Effect of acupotomy on chondrocyte proliferation and expression of CyclinD1,CDK4 and CDK6 in rabbits with knee osteoarthritis显示文摘Objective:The aim of this study was to investigate the mechanism of acupotomology(Apo)in the prevention of articular cartilage destruction via the promotion of chondrocyte proliferation and chondrocyte expression of cell cycle regulators,CyclinD1,CDK4 and CDK6 in a rabbit knee osteoarthritis(KOA)model.Methods:Twenty-eight rabbits were randomly divided into a control group,an OA(osteoarthritis)model group,an Apo(acupotomology)group and EA(electro-acupuncture)group(n Z 7).Improved Videman’s method was used to induce a rabbit model of KOA over 6 weeks.One week later,acupotomy and electro-acupuncture therapy was applied to animals in the respective groups and treatment lasted 4 weeks.Following these treatments,quantitative real-time PCR,immunohistochemical staining and western blotting were performed to assess the mRNA and protein levels of cell cycle regulators CyclinD1(Cell cycle protein D1),CDK4(Cyclin-dependent kinase 4)and CDK6(Cyclin-dependent kinase 6).Ethology measures and knee morphology were also compared among groups.Results:The Lequesne MG index score of morphology was increased(P<.01),and the passive range of motion(PROM)and the mRNA and protein levels of CyclinD1,CDK4,and CDK6 were significantly decreased(P<.01)in the OA model compared with the control group.The Lequesne MG index score and the morphology score were decreased in the Apo and EA group compared with the OA model group(P<.05 or P<.01),while the mRNA levels of CyclinD1,CDK4,and CDK6,and the protein levels of CDK4 were increased in the Apo and EA groups compared with the OA model group(P<.05 or P<.01).The PROM,and the protein levels of CyclinD1 and CDK6 were increased(P<.05)in the Apo group compared with the OA model group,while the PROM and the protein levels of CyclinD1 and CDK6 in the EA group were not significantly different(P>.05).Compared with the EA group,the morphology score was decreased in Apo group(P<.05).Conclusions:The mRNA levels of CyclinD1 and CDK4,and the protein level of CDK4 in chondrocytes are regulate by both Apo and EA.Apo is more effective than EA in regulating the protein levels of CyclinD1 and CDK6.According to the observed changes in morphology and cytokine levels,acupotomy can promote chondrocyte proliferation and can alleviate the destruction of articular cartilage in a model of KOA.Yang Gao Tong Wang Wei Zhang Xiaowei Shi Shining Ma Lijuan Wang Shuai Zhou Defeng Wang Meyer Magali Changqing Guo 2019Journal of Traditional Chinese Medical Sciences2019,6,3:2
13High-efficiency electrocatalytic NO reduction to NH_(3) by nanoporous VN显示文摘Electrocatalytic NO reduction reaction to generate NH_(3)under ambient conditions offers an attractive alternative to the energy-extensive Haber-Bosch route;however,the challenge still lies in the development of cost-effective and high-performance electrocatalysts.Herein,nanoporous VN film is first designed as a highly selective and stable electrocatalyst for catalyzing reduction of NO to NH_(3)with a maximal Faradaic efficiency of 85%and a peak yield rate of 1.05×10^(-7)mol·cm^(-2)·s^(-1)(corresponding to 5,140.8mg·h^(-1)·mg_(cat).^(-1))at-0.6 V vs.reversible hydrogen electrode in acid medium.Meanwhile,this catalyst maintains an excellent activity with negligible current density and NH_(3)yield rate decays over 40 h.Moreover,as a proof-of-concept of Zn-NO battery,it delivers a high power density of 2.0 mW·cm^(-2)and a large NH_(3)yield rate of 0.22×10^(-7)mol·cm^(-2)·s^(-1)(corresponding to 1,077.1mg·h^(-1)·mg_(cat).^(-1)),both of which are comparable to the best-reported results.Theoretical analyses confirm that the VN surface favors the activation and hydrogenation of NO by suppressing the hydrogen evolution.This work highlights that the electrochemical NO reduction is an eco-friendly and energy-efficient strategy to produce NH_(3).Defeng Qi Fang Lv Tianran Wei Mengmeng Jin Ge Meng Shusheng Zhang Qian Liu Wenxian Liu Dui Ma Mohamed SHamdy Jun Luo Xijun Liu 2022Nano Research Energy2022,1,2:2
14Heterogeneous reaction of NO_2 on the surface of montmorillonite particles显示文摘The studies on heterogeneous reactions over montmorillonite,which is a typical 2:1 layered aluminosilicate,will benefit to the understanding of heterogeneous reactions on clay minerals.Montmorillonite can be classified as sodium montmorillonite or calcium montmorillonite depending on the cation presented between the different layers.Using diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS),the heterogeneous reaction mechanism of NO2 on the surface of montmorillonite was firstly investigated.Results showed that the reaction of NO2 on the surface of sodium and calcium montmorillonite fit a first-order kinetics,and the reaction duration of calcium montmorillonite was longer than that of sodium montmorillonite under the dry condition.For either sodium or calcium montmorillonite,the uptake coefficient decreased as humidity increased.Zefeng Zhang Jing Shang Tong Zhu Hongjun Li Defeng Zhao Yingju Liu Chunxiang Ye 2012Journal of Environmental Sciences2012,24,10:2
15Development and transition of rice planting in China显示文摘Zhang Yuping Zhu Defeng 0,,06:1
16Origin, dissemination and entry of the pandemic Zika viruses显示文摘Zika 病毒(ZIKV ) 是打扫了大多数西方的半球的以前忽视,却最新新兴的 zoonotic 病原体。意外注意在新生儿在在 2015 ZIKV 散布到巴西和美国的炸药和它的稀罕关联引起了世界范围的谎言到头小畸型,提起对公共健康的严肃的挑战。我们证明起源和这些流行 ZIKA 的快传播孤立。种系发生的分析表明最新新兴的 ZIKV 孤立的所有属于亚洲美国人的系。ZIKV E 表面蛋白质的结构的分析建议它可能采用类似的入口机制到另外的 Flavi 病毒相似登革热病毒和韦斯特尼罗河病毒的。Huimin Zhang Swaminath Srinivas Defeng Li Youjun Feng 2016Science Bulletin2016,61,10:1
17Effects of calcium ions on solubility and aggregation behavior of an anionic sulfonate Gemini surfactant in aqueous solu- tions显示文摘YU Defeng WANG Yingxiong ZHANG Jian 2012Journal of Colloid and Interface Science2012,381,1:1
18Characterization and overexpression of a-hydrogenase gene of a novel hydrogen-producing bacterium ethanoligenens harbinense显示文摘ZHAO XIN XING DEFENG ZHANG LU 2010International Journal of Hydrogen Energy2010,35,:1
19Provenance System Analysis of the Nantun Formation of the Huhehu Sag in Hailar Basin显示文摘Huhehu Sag is a new battlefield for the future oil and gas exploration in the Hailar Basin.At present,exploration of this area stays at a low level and the understanding of the provenance system of the Nantun Formation is comparatively weak.So,to carry out the detailed depiction of the provenance system in the study area is significant for the sedimentary system reconstruction,for the prediction of reservoir distribution and favorable areas.Based on comprehensive analysis of paleogeomorphy,light-heavy mineral and seismic reflection features,sandstone thickness and sandstone percentage,this paper analyzes in detail the provenance system of the Nantun Formation in Huhehu Sag from various angles and levels.It shows that provenances of the Huhehu Sag mainly originated from the eastern Xilinbeier Salient and western Bayan Mountain Uplift.The provenances surrounding the lake basin converged to the center of the basin,among which,the steep slope belt and the gentle slope belt are the main provenances,and the southern uplift is a secondary one.The distribution framework of the provenance fundamentally determines the distribution rules of the depositional system and its sand body developing during the Nantun period.LI Junhui MENG Qi'an LU Shuangfang ZHU Defeng WU Haibo LIU He ZHANG Dazhi 2012Acta Geologica Sinica(English Edition)2012,86,1:1
20Heterogeneous reaction of NO_2 with sea salt particles显示文摘To understand how NO2 reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2 on the surface of wet sea salt was investigated with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Kinetic measurements indicated that nitrate formation on sea salt was second order in NO 2 concentration and reactive uptake coefficients were (5.51 ± 0.19) × 10-7 and 1.26 × 10-6 respectively under 0% and 20% relative humidity (RH) at NO 2 molecular concentration of 1.96 × 1015 mol/cm3.The results showed that liquid water was formed at the site of MgCl2·6H2O,CaCl2·2H2O on the surface of sea salt and made the reaction more sustainable by releasing hydrated water and absorbing water from air even under a low RH (30%).Therefore,pure NaCl particles should not be used to represent sea salt in studies of the heterogeneous reaction with NO2.YE ChunXiang 1,LI HongJun 1,ZHU Tong 1,SHANG Jing 1,ZHANG ZeFeng 1,2 & ZHAO DeFeng 1 1 State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China 2 College of Atmospheric Physics,Nanjing University of Information Science and Technology,Nanjing 210044,China 2010Science China Chemistry2010,53,12:1
返回顶部 每页显示:
共4页 首页 上一页 第1页 下一页 末页 /4 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费