187 resultados para CSR indicators


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A comparative limnological study was carried out to present a snapshot of crustacean zooplankton communities and their relations to environmental factors to test whether there is a consistent relationship between crustacean biomass and trophic indicators among lake groups with similar trophic conditions. The study lakes showed a wide range of trophic status, with total phosphorus (TP) ranging from 0.008 to 1.448mgL(-1), and chlorophyll a from 0.7 to 146.1 mu g L-1, respectively. About 38 species of Crustacea were found, of which Cladocera were represented by 25 taxa (20 genera), and Copepoda by 13 taxa (I I genera). The most common and dominant species were Bosmina coregoni, Moina micrura, Diaphanosoma brachyurum, Cyclops vicinus, Thermocyclops taihokuensis, Mesocyclops notius and Sinocalanus dorrii. Daphnia was rare in abundance. Canonical correspondence analysis showed that except for four species (D. hyalina, S. dorrii, C. vicinus and M. micrura), almost all the dominant species had the same preference for environmental factors. Temperature, predatory cyclopoids and planktivorous fishes seem to be the key factors determining species distribution. TP was a relatively better trophic indicator than chlorophyll a to predict crustacean biomass. Within the three groups of lakes, however, there was no consistent relationship between crustacean biomass and trophic indicators. The possible reason might be that top-down and bottom-up control on crustaceans vary with lake trophic state. The lack of significant negative correlation between crustacean biomass and chlorophyll a suggests that there was little control of phytoplankton biomass by macrozooplankton in these shallow subtropical lakes. (c) 2007 Elsevier GmbH. All rights reserved.

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HIRFL-CSR, a new heavy ion cooler-storage-ring system at IMP, had been in commissioning since the beginning of 2006. In the two years of 2006 and 2007 the CSR commissioning was finished, including the stripping injection (STI), electron-cooling with hollow electron beam, C-beam stacking with the combination of STI and e-cooling, the wide energy-range synchrotron ramping from 7 MeV/u to 1000 MeV/u by changing the RF harmonic-number at mid-energy, the multiple multi-turn injection (MMI), the beam accumulation with MMI and e-cooling for heavy-ion beams of Ar, Kr and Xe, the fast extraction from CSRm and single-turn injection to CSRe, beam stacking in CSRe and the RIBs mass-spectrometer test with the isochronous mode in CSRe by using the time-of-flight method.

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In commissioning the HIRFL-CSR (Cooler Storage Ring of Heavy Ion Research Facility in Lanzhou),with the spectrum analyzer monitoring the beams on-line, we measured many parameters of the beam status for improving quality of the heavy ion beams. In this paper, the sudden change of the beam center frequency is analyzed.A theoretical analysis is done mainly on instabilities of the electron voltage and the neutralization factor. Simulations were made for the problem. According to the simulation result, we can conclude that it is the instability of neutralization factor that caused the problem. 中文摘要:HIRFL-CSR调试过程中,利用频谱分析仪实时监测束流,根据其上测的数据进行相关参数调整,改善束流的品质。本文对分析仪上观测到的现象一束流的中心频率发生突变进行了研究,主要就电子束的高压不稳定性和中性化因子的突变做了理论分析,并进行了相关的模拟计算 ,根据模拟结果初步断定该现象的出现由电子束的中性化因子导致。

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The HIRFL-CSR EVME bus controller, which runs Embedded Linux OS, is based on AT91RM9200 microprocessor, whose core is ARM920T. There are hardware interface electronic circuits connecting AT91RM9200 microprocessor and Security Digital Memory Card (SD Card). This article analyzes Operation System kernel and Linux device driver’s structure, designs SD Card driver based on Embedded Linux, which runs on AT91RM9200 microprocessor.中文文摘:简要论述了用于兰州重离子加速器冷却储存环(HIRFL-CSR)控制系统的前端总线控制器。该控制器是基于ARM920T核心的AT91RM9200处理器,运行嵌入式Linux操作系统。描述了AT91RM9200处理器与Security Digital MemoryCard(SD卡)的硬件接口电路,分析了操作系统内核和Linux驱动程序结构,设计和实现了嵌入式Linux下基于AT91RM9200处理器的SD卡驱动程序。

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This paper discuss a Ion-pump Power Supply control system making use of RS232 series bus and Intranet.The system s hardware VAC800 is composed of MSP430F149 mixed-signal processors produced by TI and UA7000A network model.MSP430F149 has advantages of ultra-low-power and high-integration.The Ion-pump Power Supply control system has the characteristics of strong function,simple structure,high reliability,strong resistance of noise,no peripheral chip,etc.Visual studio 2005 is used to design the system s softwa...中文文摘:论述了通过RS-232总线和Intranet网络,来实现对远端的离子泵电源的监测与控制。系统硬件VAC800由TI公司的MSP430F149混合信号处理器和UA7000A网络模块构成。MSP430F149具有超低功耗和高集成度等优点,利用它构建的离子泵电源监控系统功能强大,结构简单,可靠性高,抗干扰能力强。系统软件采用visual studio 2005设计。本监控系统能够很好地完成对加速器离子泵电源监视与控制。

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This paper introduced a real-time vacuum monitor system based on multilayer Web architecture for HIRFL-CSR(Heavy Ion Research Facility of Lanzhou & Cooler Storage Ring) project in Lanzhou.It combined with COM/DCOM to develop the application layer,and developed the web layer with ActiveX and Ajax technology.It provided a facility and efficiency method for real-time control.The application shows that this system runs stably and accurately.中文文摘:简要介绍了国家"九五"重大科学工程——兰州重离子加速器冷却储存环(HIRFL-CSR)真空监控系统的总体结构,分析了在Web构架下,基于分布式内存数据库的多层真空监控系统的实现方法。采用分布式内存数据库,解决了基于Web构架的分布式实时应用环境下对系统和网络资源的消耗问题。在软件控制方面采用了统一调度,既简化了软件实现过程,又提高了系统的安全性、高效性和易维护性。该系统已成功运行。

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