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Metabolic Characteristics and Functional Diversity of Carbon Source in Microflora of Ponds with Recirculating Aquaculture System 被引量:2
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作者 李谷 宋景华 +3 位作者 李晓莉 张世羊 陶玲 张春雪 《Agricultural Science & Technology》 CAS 2014年第2期278-282,299,共6页
With Biolog Eco microplate, metabolic characteristics and functional diver-sity of carbon source in microflora of ponds were researched based on recitculating ponds and control ponds in order to explore effects of eco... With Biolog Eco microplate, metabolic characteristics and functional diver-sity of carbon source in microflora of ponds were researched based on recitculating ponds and control ponds in order to explore effects of eco-adjustments on microflo-ra in ponds. The results indicate that total number of bacterium, microbial metabolism activity, and diversity index in P7, P8, P1 and P2 kept higher, fol owed by P3, P4, P5 and P6. The utilization rate of microbes on sugars achieved the highest (31.0%-48.7%), fol owed by carboxylic acid (13.4%-18.0%), amino acid (10.1%-20.5%), polymers (9.4%-17.0%), biopolymer (5.7%-9.7%) and phenol (4.95%-7.50%). Principal component analysis divided microflora in different ponds, suggesting that microbial community has varied carbon source characteristics and nitrogen-containing compound and biopolymer metabolisms are most affected. 展开更多
关键词 Aquaculture pond MICROBE -Metabolic characteristics of carbon source Functional diversity
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Study on the Source Characteristics of Downhole Airgun with Different Excitation Environments 被引量:2
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作者 Yang Wei Wang Baoshan +3 位作者 Liu Zhengyi Yang Jun Li Xiaobin Chen Yong 《Earthquake Research in China》 CSCD 2016年第3期342-354,共13页
The measurement of underground medium variation using a repeated artificial source has gradually become an important goal to pursue. In recent years,we have developed and improved a technology system with large capaci... The measurement of underground medium variation using a repeated artificial source has gradually become an important goal to pursue. In recent years,we have developed and improved a technology system with large capacity airguns excited in land reservoirs by transplanting marine seismic exploration technology. The excitation effect has a close relationship to airgun capacity,water environment,and excitation conditions. In view that large capacity airgun must be excited without a water environment,we expand the system to use in downhole. Based on the BHS-2200 LL downhole airgun with a capacity of250in3,this paper carries out a comparative analysis on the characteristics of an airgun source excited in 0. 2m- and 5. 0m-diameter wells,and the results show that:( 1) The dominant frequency of the airgun signal excited in a 5. 0m well is mainly from 10 Hz to40Hz,lower than that in a 0. 2m well,and the larger body of water is good for bubble oscillation.( 2) In terms of exciting energy,the signal excited in a 5. 0m well has stronger energy than in a 0. 2m well,with a difference of 1 order in magnitude,and the signal can be detected up to 9km excited in a 5. 0m well with a single shot.( 3) The airgun signal has good repeatability in both excitation wells. The downhole airgun excitation technology system has potential application in dynamic monitoring near a fault zone with a small scale range, exploration of oil and mineral resources, and modern urban geophysical environment. 展开更多
关键词 Artificial source Downhole airgun Excitation environment Seismic source characteristics REPEATABILITY
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Characteristics of Rearranged Hopanes of Hydrocarbon Source Rocks in Saline Sedimentary Environment: A Case Study of the Songliao Basin 被引量:1
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作者 JIANG Lian ZHANG Min +1 位作者 LI Hongbo XIAO Qilin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2269-2270,共2页
The Songliao Basin, one of the biggest continental petroliferous basins in eastern China, is a Mesozoic- Cenozoic fault-depressed and fault-subsided basin developed on the Hercynian fold basement. Generally, rearrange... The Songliao Basin, one of the biggest continental petroliferous basins in eastern China, is a Mesozoic- Cenozoic fault-depressed and fault-subsided basin developed on the Hercynian fold basement. Generally, rearranged hopanes are considered to be formed by clay- mediated acidic catalysis under oxic or suboxic environment, whereas high abundance of rearranged hopanes were found in hydrocarbon source rocks and crude oils that are derived from salty environment in the Songliao Basin. This phenomenon rarely happens all over the world. 展开更多
关键词 BA characteristics of Rearranged Hopanes of Hydrocarbon source Rocks in Saline Sedimentary Environment
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Molecular Biomarker Characteristics of the Linxi Formation Source Rocks in the Middle-Western Region of Inner Mongolia:New evidence for late-stage tectonic evolution of the Paleo-Asian Ocean 被引量:1
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作者 ZHANG Yongsheng PENG Yuan +3 位作者 SHI Lizhi XING Enyuan GUI Baolin LI Kai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期745-746,共2页
Objective Two important geological issues have long been controversial in the Xing-Meng area of North China. The first concerns the final closure of Paleo-Asian Ocean in Xing-Meng area, and the other concerns the fol... Objective Two important geological issues have long been controversial in the Xing-Meng area of North China. The first concerns the final closure of Paleo-Asian Ocean in Xing-Meng area, and the other concerns the folding and lifting of the Xing-Meng Trough. The focus of thses issues is the Late Permian sedimentary environment, which is generally considered to be either an exclusively continental environment or from the closed inland sea environment in the Early to Middle stage to continental lacustrine environment in the late stage. In recent years, we have successively discovered abundant typical marine fossils (e.g., bryozoans and calcareous algae) in the Upper Permian thick limestone layer from Linxi County and Ar Horqin Banner in eastern region of Inner Mongolia and Jiutain County in Jilin Province. These significant findings have attracted the attention from fellow academics. 展开更多
关键词 In As Molecular Biomarker characteristics of the Linxi Formation source Rocks in the Middle-Western Region of Inner Mongolia:New evidence for late-stage tectonic evolution of the Paleo-Asian Ocean
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Characteristics of Resistance Triggering of a Pulsed Vacuum Arc Ion Source 被引量:1
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作者 蓝朝晖 龙继东 +4 位作者 郑乐 董攀 杨振 王韬 李杰 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期84-87,共4页
Triggering scheme is a significant factor that may influence the process of vacuum arc initiation. In this work, the characteristics of resistance triggering of a pulsed vacuum arc ion source are investigated and comp... Triggering scheme is a significant factor that may influence the process of vacuum arc initiation. In this work, the characteristics of resistance triggering of a pulsed vacuum arc ion source are investigated and compared with the independent pulse generator triggering. The results show that although the resistance triggering method is capable of triggering a vacuum arc ion source by properly choosing the resistance and electric parameters, it inevitably increases the rise time of the arc current. A high speed multiframe camera is used to reveal the transition process o~ arc initiation during one shot. From the images it is conjectured that the lower voltage between the cathode and the anode may be the reason that leads to the lower transition speed of discharge at the moment of arc initiation. 展开更多
关键词 In characteristics of Resistance Triggering of a Pulsed Vacuum Arc Ion source ARC
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Ore-forming fluid characteristics and ore-forming materials source of the Tudimiaogou – Yindongshan lead-zinc polymetallic orefield, west Henan
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作者 TAN Huajie SHAO Yongjun +4 位作者 ZHENG Minghong ZHOU Houdi ZHANG Jiandong PENG Guangxiong Cheng Luping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期227-228,共2页
1 Introduction The Tudimiaogou-Yindongshan lead-zinc polymetallic orefield is located in the Tudimiaogou-Weimoshi lead and zinc silver polymetallic metallogenic belt.The belt is an important part of southwestern Henan... 1 Introduction The Tudimiaogou-Yindongshan lead-zinc polymetallic orefield is located in the Tudimiaogou-Weimoshi lead and zinc silver polymetallic metallogenic belt.The belt is an important part of southwestern Henan lead and zinc 展开更多
关键词 In Pb rock west Henan Ore-forming fluid characteristics and ore-forming materials source of the Tudimiaogou Yindongshan lead-zinc polymetallic orefield
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Geochemical Characteristics of the Source Rocks in Mesozoic Yanchang Formation,Central Ordos Basin 被引量:7
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作者 林森虎 袁选俊 +2 位作者 陶士振 杨智 吴松涛 《Journal of Earth Science》 SCIE CAS CSCD 2013年第5期804-814,共11页
The shale of Yanchang Formation in Upper Triassic is the most important source rock for the Mesozoic petroleum reserviors in Ordos Basin. Chang 7 and Chang 4+5 members are the major source rock formation. Source rock... The shale of Yanchang Formation in Upper Triassic is the most important source rock for the Mesozoic petroleum reserviors in Ordos Basin. Chang 7 and Chang 4+5 members are the major source rock formation. Source rock samples, obtained from 22 cored wells in central Ordos Basin, were geochemically analyzed to determine the organic matter abundance, kerogen type and thermal maturity. Total organic carbon values ranged from 0.36% to 19.10%, 8.09% on average, in- dicating a good source rock potential. In this area, the shale is mature, as indicated by vitrinite re- flectance values. RockoEval data revealed that the samples are dominated by type II kerogen. Com- pare the Chang 7 and Chang 4+5 members, which suggests that the Chang 7 shale has higher TOC, especially the highest lower Chang 7 members. The abundance of organic matter of Chang 4+5 and Chang 7 members is both richest in southeast basin. The kerogen type of Chang 4+5 and upper Chang 7 members is type II~, the counterpart of middle and lower Chang 7 member is type I. During the burial history, the total hydrocarbon-generating quantity of Chang 7 member is much more than that of Chang 4+5 members. 展开更多
关键词 hydrocarbon-generating potential geochemical characteristics of source rock Meso- zoic Yanchang Formation Ordos Basin.
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Characteristic studies of heat sources and performance analysis of free-cooling assisted air conditioning and ventilation systems for working faces of mineral mines
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作者 Rang Tu Lijuan Huang +2 位作者 Aibing Jin Mingfeng Zhang Xiao Hai 《Building Simulation》 SCIE EI CSCD 2021年第6期1725-1736,共12页
High temperature heat hazard at mineral mine becomes more and more serious as the increase of mining depth.Heat sources at working faces of mineral mines are complex and are of different characteristics,presenting new... High temperature heat hazard at mineral mine becomes more and more serious as the increase of mining depth.Heat sources at working faces of mineral mines are complex and are of different characteristics,presenting new challenges for air conditioning systems.In this paper,heat sources at four types of working faces are summarized and their characteristics are investigated.Based on this,simplified equations,which are linear with length of working faces,are proposed to calculate heat dissipation rates.So that the main heat sources of different working faces can be found,and cooling load of air conditioning systems can be calculated.Then,considering main heat sources of coal mines,a typical working face is designed to investigate performances of different ventilation systems and air conditioning systems.Simulation results show that segmented ventilation systems(SC)and heat shield assisted centralized ventilation systems(CCHS)can realize much better temperature distributions at working faces.However,cooling load can be greatly reduced for CCHS,when untreated air is supplied to the coal seam side.Based on this,free cooling assisted air conditioning systems are designed,and annual average energy efficiency ratio(EERann)of the systems are investigated and compared between direct evaporate cooling and indirect evaporate cooling(IEC).For SC,as compared with scenarios without free-cooling,IEC can increase EERann by 15%-23%and 22%-32%under Benxi and Datong ambient conditions,respectively.Besides,to ensure high EERann,CCHS is preferred and it is essential to increase thermal insulation of air ducts. 展开更多
关键词 working face heat sources characteristics air ventilation system free cooling air conditioning energy efficiency
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STUDY ON THE STABILITY STRUCTURE OF SYNOPTIC SCALE SYSTEMS,THE BIFURCATION OF PHASE.PATH CHARACTERISTICS AND THE INFLUENCE OF THE TIME-OSCILLATION OF HEAT SOURCE 被引量:1
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作者 徐祥德 《Acta meteorologica Sinica》 SCIE 1989年第1期83-89,共7页
This paper discusses the stability structure and the bifurcation of phase path characteristics of synoptic scale system.The analytic results show that the catastrophe of the synoptic scale disturbance may be caused by... This paper discusses the stability structure and the bifurcation of phase path characteristics of synoptic scale system.The analytic results show that the catastrophe of the synoptic scale disturbance may be caused by the nonlinear effects of barotropic and baroclinic instability and advection of ambient large-scale flow.Also, foregoing nonlinear effects on the speed of development and decay of the system are presented in the processes deviating from or approaching to equilibrium state.It has been found that there is a resonance phenomenon between the time-oscillation of heat source and the atmospheric disturbance. 展开更多
关键词 STUDY ON THE STABILITY STRUCTURE OF SYNOPTIC SCALE SYSTEMS THE BIFURCATION OF PHASE.PATH characteristicS AND THE INFLUENCE OF THE TIME-OSCILLATION OF HEAT source
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Source,route and effect of Asian sand dust on environment and the oceans 被引量:3
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作者 Kai Zhang Fahe Chai +1 位作者 Renjian Zhang Zhigang Xue 《Particuology》 SCIE EI CAS CSCD 2010年第4期319-324,共6页
We summarize in this overview achievements in current research frontiers in Asian sand dust with emphasis on the method for sand dust research, the sources of sand dust aerosols, emission of sand dust, mechanism of sa... We summarize in this overview achievements in current research frontiers in Asian sand dust with emphasis on the method for sand dust research, the sources of sand dust aerosols, emission of sand dust, mechanism of sand dust weather, chemical transformation during transport, and influences on climatic environment and oceans. Our main results show that most of Asian sand dust comes from Mongolia, the Gobi Desert, arid and semiarid desert areas in northwest China, which is divided into initial sources and enhanced sources. Half of the global production of dust originates from Asian dust source regions. Asian dust weather is so immense that it can cover a 5-?-day journey from the sources to the Korean Peninsula, Japan Islands, and the Pacific Ocean to even impact North America. Asian dust weather plays an active role in the hiogeochemical cycles of trace elements in the mid-latitude Northern Hemisphere. 展开更多
关键词 Asian sand dust characteristic source Transport
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Quantifying the characteristics of particulate matters captured by urban plants using an automatic approach 被引量:3
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作者 Jingli Yan Lin Lin +2 位作者 Weiqi Zhou Lijian Han Keming Ma 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第1期259-267,共9页
It is widely accepted that urban plant leaves can capture airborne particles. Previous studies on the particle capture capacity of plant leaves have mostly focused on particle mass and/or size distribution. Fewer stud... It is widely accepted that urban plant leaves can capture airborne particles. Previous studies on the particle capture capacity of plant leaves have mostly focused on particle mass and/or size distribution. Fewer studies, however, have examined the particle density, and the size and shape characteristics of particles, which may have important implications for evaluating the particle capture efficiency of plants, and identifying the particle sources. In addition, the role of different vegetation types is as yet unclear. Here, we chose three species of different vegetation types, and firstly applied an object-based classification approach to automatically identify the particles from scanning electron microscope(SEM)micrographs. We then quantified the particle capture efficiency, and the major sources of particles were identified. We found(1) Rosa xanthina Lindl(shrub species) had greater retention efficiency than Broussonetia papyrifera(broadleaf species) and Pinus bungeana Zucc.(coniferous species), in terms of particle number and particle area cover.(2) 97.9% of the identified particles had diameter ≤10 μm, and 67.1% of them had diameter ≤2.5 μm. 89.8% of the particles had smooth boundaries, with 23.4% of them being nearly spherical.(3) 32.4%–74.1% of the particles were generated from bare soil and construction activities, and 15.5%–23.0% were mainly from vehicle exhaust and cooking fumes. 展开更多
关键词 Particulate matter retention Urban vegetation Object-based classification Size and shape characteristics source identification
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