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一种低功耗智能IC卡冷水表的设计与实现 被引量:6
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作者 康叶伟 黄亚楼 孙凤池 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第5期14-17,共4页
给出了一种低功耗智能IC卡冷水表的软硬件设计方案与实现方法[1,2],该智能冷水表具有水量显示、水量累计,电磁阀控制,操作记录,防强磁场干扰,防拆,欠压报警等功能,独特的低功耗设计大大延长了水表的有效使用寿命.该方法实现的水表经实... 给出了一种低功耗智能IC卡冷水表的软硬件设计方案与实现方法[1,2],该智能冷水表具有水量显示、水量累计,电磁阀控制,操作记录,防强磁场干扰,防拆,欠压报警等功能,独特的低功耗设计大大延长了水表的有效使用寿命.该方法实现的水表经实际测试,性能指标已达到实际应用的要求,是一种具有推广应用价值的产品. 展开更多
关键词 智能IC卡冷水表 低功耗 防磁
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基于PLC的一种冷水表全自动检定装置的研究 被引量:2
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作者 郭学军 殷晓菁 +1 位作者 宋兴芳 王艳霞 《工业仪表与自动化装置》 2020年第3期72-74,共3页
为了提高冷水表的检定效率和检定精度,提出基于西门子S7-200 SMART PLC的冷水表全自动检定装置。通过PLC对管道气动阀门、水泵和变频器的自动控制,对标准电磁流量计的数据采集和换算,实现了《JJG 162—2009冷水水表检定规程》中对常用... 为了提高冷水表的检定效率和检定精度,提出基于西门子S7-200 SMART PLC的冷水表全自动检定装置。通过PLC对管道气动阀门、水泵和变频器的自动控制,对标准电磁流量计的数据采集和换算,实现了《JJG 162—2009冷水水表检定规程》中对常用、分界、最小流量的冷水表自动检定流程。该装置能节约大量人工检定时间,提高检定准确度,延长使用寿命,降低运营成本。 展开更多
关键词 自动检定装置 PLC 流量计 冷水表
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冷水表示值误差测量值的不确定度的评定
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作者 梁芳 《计量与测试技术》 2014年第11期79-80,共2页
本文详细介绍了评定2级冷水表示值误差测量结果不确定度的原理、模型和方法,并对一只准确度等级为2级的冷水表在Q3、Q2、Q1点测量,报告评定其示值误差测量结果的相对扩展不确定度。
关键词 冷水表 示值误差 不确定度 评定
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智能IC卡水表售水软件系统的设计与实现
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作者 左莉 《大众科技》 2008年第5期28-29,共2页
文章给出了一种智能IC卡冷水表的售水软件系统的设计与实现,该系统提供用户管理,IC卡充值、挂失、更换操作,费率设置,用户记录管理,数据库维护等功能,便捷实用的功能为IC卡水表的售水服务提供了可靠保证,实际测试表面系统工作性能稳定。
关键词 智能IC卡冷水表 数据库 售水系统
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AtpH Is a Chilling-Repressed Gene in Rice 被引量:1
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作者 毛兴学 庄楚雄 +4 位作者 彭新湘 梅曼彤 缪征新 郭振飞 李明启 《Acta Botanica Sinica》 CSCD 2003年第4期484-487,共4页
A chilling-repressed cDNA fragment was cloned from rice ( Oryza sativa L.) seedlings by reverse transcription-polymerase chain reaction (RT-PCR) differential display. Database comparison of the cDNA sequence is identi... A chilling-repressed cDNA fragment was cloned from rice ( Oryza sativa L.) seedlings by reverse transcription-polymerase chain reaction (RT-PCR) differential display. Database comparison of the cDNA sequence is identical to atpH encoded by rice chloroplast genome. Northern hybridization showed that its RNA transcript was reduced greatly on the first day and fully inhibited after 2 d of chilling treatment. 展开更多
关键词 RICE CHILLING atpH
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WTO/TBT通报 计量与检验部分(三)
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《中国计量》 2003年第11期24-25,共2页
关键词 WTO/TBT通报 计量 检验 玻璃温度计 冷水表 化妆品分析 出租车法令
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Simulation of global ocean acidification and chemical habitats of shallow-and cold-water coral reefs 被引量:1
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作者 ZHENG Mei-Di CAO Long 《Advances in Climate Change Research》 SCIE 2014年第4期189-196,共8页
Using the UVic Earth System Model, this study simulated the change of seawater chemistry and analyzed the chemical habitat surrounding shallow- and cold-water coral reefs from the year 1800 to 2300 employing RCP2.6, R... Using the UVic Earth System Model, this study simulated the change of seawater chemistry and analyzed the chemical habitat surrounding shallow- and cold-water coral reefs from the year 1800 to 2300 employing RCP2.6, RCP4.5, RCP6.0, and RCP8.5 scenarios. The model results showed that the global ocean will continue to absorb atmospheric CO2. Global mean surface ocean temperature will rise 1.1-2.8 K at the end of the 21st century across RCP scenarios. Meanwhile, the global mean surface ocean pH will drop 0.14--0.42 and the ocean surface mean con- centration of carbonate will decrease 20%--51% across the RCP scenarios. The saturated state of sea water with respect to calcite carbonate minerals (t2) will decrease rapidly. During the pre-industrial period, 99% of the shallow-water coral reefs were surrounded by seawater with t2 〉 3.5 and 87% of the deep-sea coral reefs were surrounded by seawater with aragonite supersaturation. Within the 21st century, except for the high mitigation scenario of RCP2.6, almost none shallow-water coral reefs will be surrounded by seawater with g2 〉 3.5. Under the intensive emission scenario of RCP8.5, by the year 2100, the aragonite saturation horizon will rise to 308 m under the sea surface from 1138 m at the pre- industrial period, thus 73% of the cold-water coral reefs will be surrounded by seawater with aragonite undersaturation. By the year 2300, only 5% of the cold-water coral reefs will be surrounded by seawater with aragonite supersaturation. 展开更多
关键词 Simulation research Aragonite saturation state Ocean acidification Shallow-water coral reefs Cold-water coral reefs
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Experiment on Gas Hydrates Formation by Water Spraying
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作者 刘妮 刘道平 谢应明 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期489-493,共5页
An experimental investigation of natural gas hydrate formation has been conducted in a high-pressure water spraying reactor,which is cooled by the circulation water through an external cooling jacket.The results show ... An experimental investigation of natural gas hydrate formation has been conducted in a high-pressure water spraying reactor,which is cooled by the circulation water through an external cooling jacket.The results show that the morphology of hydrates formed by water spraying is like ice-slurry,which depends on the initial pressure and temperature.At a certain reaction pressure,the rate of hydrate formation is increasing with lower temperature.And also,the induction time of hydrate formation can be greatly shortened by water spraying compared to a quiescent system.Solution with appropriate surfactant sodium dodecyl sulfate (SDS) is found to improve the formation rate obviously. 展开更多
关键词 natural gas hydrate water spraying induction time MORPHOLOGY
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Long-term temperature variation of the Southern Yellow Sea Cold Water Mass from 1976 to 2006 被引量:2
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作者 李昂 于非 +1 位作者 司广成 魏传杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第5期1032-1044,共13页
This paper discusses the long-term temperature variation of the Southern Yellow Sea Cold Water Mass(SYSCWM)and examines those factors that infl uence the SYSCWM,based on hydrographic datasets of the China National Sta... This paper discusses the long-term temperature variation of the Southern Yellow Sea Cold Water Mass(SYSCWM)and examines those factors that infl uence the SYSCWM,based on hydrographic datasets of the China National Standard Section and the Korea Oceanographic Data Center.Surface air temperature,meridional wind speed,and sea surface temperature data are used to describe the seasonal changes.Mean temperature of the two centers of the SYSCWM had diff erent long-term trends.The temperature of the center in the west of the SYSCWM was rising whereas that of the center in the east was falling.Mean temperature of the western center was related to warm water intrusion of the Yellow Sea Warm Current,the winter meridional wind,and the winter air temperature.Summer process played a primary role in the cooling trend of temperature in the eastern center.A decreasing trend of salinity in the eastern half of the SYSCWM showed that warm water intrusion from the south might weaken,as could the SYSCWM circulation.Weakened circulation provided less horizontal heat input to the eastern half of the SYSCWM.Less lateral heat input may have led to the decreasing trend in temperature of the eastern center of the SYSCWM.Further,warmer sea surface temperatures and less heat input in the deep layers intensifi ed the thermocline of the eastern SYSCWM.A stronger thermocline had less heat fl ux input from upper layers to this half of the SYSCWM.Stronger thermocline and weakened heat input can be seen as two main causes of the cooling temperature trend of the eastern center of the SYSCWM. 展开更多
关键词 Southern Yellow Cold Water Mass (SYSCWM) long-term trend interaimual variability influence factor
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Analytic Method to Study Influence of Finite Chemical Potential in QED_3~*
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作者 ZHOU Yu-Qing ZONG Hong-Shi FENG Hong-Tao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期909-913,共5页
Adopting the approximation to the first order of chemical potential μ, we resolve rigidly the influence on fermion condensate from μ in QED3. We show that this condensate does not respond linear expression to μ. Mo... Adopting the approximation to the first order of chemical potential μ, we resolve rigidly the influence on fermion condensate from μ in QED3. We show that this condensate does not respond linear expression to μ. Moreover, the influence on fermion chiral condensate from chemieal potential is investigated. 展开更多
关键词 QED3 DSE finite chemical potential
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Field experiment on coalmine heat disaster governance using cold source from surface water
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作者 Guo Pingye Zhu Guolong +2 位作者 Liu Yuqing Duan Mengmeng Wu Junyin 《International Journal of Mining Science and Technology》 SCIE EI 2014年第6期865-869,共5页
Regarding the lack of cold source for underground cooling systems from either mine inflow or return air, field experiments were taken in a high temperature deep coal mine with abundant cold source from surface water. ... Regarding the lack of cold source for underground cooling systems from either mine inflow or return air, field experiments were taken in a high temperature deep coal mine with abundant cold source from surface water. Taking Sanhejian coal mine as an example, this paper introduced the technology scheme of heat disaster governance using surface water cold source. The paper presents the basics of this field experiment at the beginning, following by the design and site layout of the cooling system including the analysis and calculation of cold source. Numerical calculation method is also applied based on the operation parameters to simulate the influence to the surface river ecosystem. The results suggest that the temperature of surface water shall be lower than 34 ℃ after heat exchange, and when more cooling capacities are needed in the future, increasing the water flow is more favorable than increasing the cooling range of water, which is better for the ecological environment protection, 展开更多
关键词 Deep mine Heat disaster Surface water Cold source
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DNA Methylation Analysis of Cassava (Manihotesculenta Crantz) SC8 and Its Autotetraploid in Response to Cold Stress 被引量:1
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作者 Xue Jing jing Li Kaimian Chen Songbi 《Journal of Food Science and Engineering》 2017年第6期297-304,共8页
DNA methylation plays a vital role in the regulation of gene expression in response to environmental stress. However, little is known about the effect of DNA methylation on the cassava polyploidy. In the present study... DNA methylation plays a vital role in the regulation of gene expression in response to environmental stress. However, little is known about the effect of DNA methylation on the cassava polyploidy. In the present study, methylation-sensitive amplified polymorphisms (MSAP) were used to investigate DNA methylation profiles of cassava polyploidy following cold treatment to identify candidate genes involved in response to cold stress. The result showed that the genome-wide DNA methylation polymorphisms accounted for 34.02%-42.56% in SC8 and its autotetraploid exposed to 5 ~C for 2, 8, 24 and 48 h, respectively. The methylation levels of SC8 at 2 h-cold stress were the highest during 48h under cold treatments. With the time extension within 48 h under cold stress, the methylation levels gradually decreased to the same level as the control but DNA methylation levels of cassava autotetraploid were stable within 48 h. For future analysis of the methylation extent, the cold stress induced more DNA methylation than demethylation in SC8, where DNA methylation was consistent with demethylation in its autotetraploid. The expression analysis demonstrated increase in the transcription of one methylated gene and decrease in the transcription of two demethylated genes. The results revealed that gene methylations in specific sites would be a rapidly epigenetic response to cold stress, further elucidating the methylation functions in its autotetraploid. 展开更多
关键词 Cassava SC8 tissue culture seedling MSAP cold stress.
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An experimental investigation into the icing and melting process of a water droplet impinging onto a superhydrophobic surface 被引量:5
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作者 JIN ZheYan JIN SongYue YANG ZhiGang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第11期2047-2053,共7页
The freezing and melting process of a small water droplet on a superhydrophobic cold surface was investigated using the Laser Induced Fluorescence(LIF)technique.The superhydrophobic surface was prepared using a sol-ge... The freezing and melting process of a small water droplet on a superhydrophobic cold surface was investigated using the Laser Induced Fluorescence(LIF)technique.The superhydrophobic surface was prepared using a sol-gel method on a red copper test plate.From the obtained fluorescence images,the phase transition characteristics during the freezing and melting process of a water droplet were clearly observed.It was found that,at the beginning of the droplet freezing process,liquid water turned into ice at a very fast rate.Such phase transition process decreased gradually with time and the volume of frozen ice approached a constant value at the end of the icing process.In addition,the freezing time was found to reduce with the decrease of the test plate temperature.Besides,when the test plate temperature is relatively high,the effect of droplet volume on the freezing time is very significant.Over all,we provide some tentative insights into the microphysical process related to the icing and melting process of water droplets. 展开更多
关键词 SOL-GEL ICING MELTING superhydrophobic surface water droplet
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Analysis of surface and sub-surface of cold-rolled Al plate lubricated with water-or oil-based lubricants 被引量:1
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作者 TANG XiWen ZHANG ChenHui +2 位作者 WANG Yan YANG Ye HU Juan 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第9期1407-1414,共8页
For environmental protection, energy conservation, and other reasons, water-based lubricants are increasingly chosen to replace oil lubricants. Water-based lubricants are divided into emulsified and solution types. So... For environmental protection, energy conservation, and other reasons, water-based lubricants are increasingly chosen to replace oil lubricants. Water-based lubricants are divided into emulsified and solution types. Solution type water-based lubricants have attracted significant attention for the good stability, easy biodegradability, and safety for workers. However, some problems exist with current solution type water-based lubricants, such as poor lubricity and corrosion resistance. During the cold-rolling process, A1 plate rolled using oil-based lubricant lubrication shows metallic luster, but that rolled using water-based lubricant shows corrosion spots, black strips, and no metallic luster. Therefore, this study mainly analyzed the reasons for the darkness of A1 plate cold-rolled with water solution lubricants. The differences in plate surfaces lubricated by water solution and oil were investigated by scanning electron microscopy, auger electron spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The analysis results showed that the surface of the oil-lubricated sample is smooth, the oxygen content is low, and the oxide layer is thin, while the surface of the water solution-lubricated sample is rough, the oxygen content is high, the chemical composition is more complex, and the oxide layer is not uniform and thick. 展开更多
关键词 water-based lubricant oil-based lubricant cold-rolled al surface oxidation
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