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论《金匮要略》水气病之在气在水在血 被引量:2
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作者 江泳 陈建杉 《浙江中医杂志》 北大核心 2004年第8期325-327,共3页
关键词 《金匮要略》 在气 在水 在血 中医
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亚毫米波大气传输计算及分析 被引量:1
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作者 唐义平 李兴国 +1 位作者 李卫 罗正发 《上海航天》 1997年第1期13-20,共8页
主要研究了在近亚毫米波段的大气传输特性。通过分析远红外区和毫米波区的大气传输模型,给出了亚毫米波段的大气传输模型以及加权项的表达形式。在吸收模型的理论分析的基础上,推导了以宏观气象条件为参变量的解析表达式,并由实验数... 主要研究了在近亚毫米波段的大气传输特性。通过分析远红外区和毫米波区的大气传输模型,给出了亚毫米波段的大气传输模型以及加权项的表达形式。在吸收模型的理论分析的基础上,推导了以宏观气象条件为参变量的解析表达式,并由实验数据对加权后的模型进行了验证分析。加权模型与实验数据基本吻合。在散射模型中,提出了以粒子的统计分布均值代替一般的密度分布,从而提高了计算精度。分别推导了Mie和Rayleigh散射系数求解的数学表达式。模拟计算结果与实验分析是一致的。由于空气中以气溶胶形式存在的粒子为多数,且粒子尺寸各异,对同一波长的散射表现不同。 展开更多
关键词 亚毫米波传播 传输 在气吸收 散射
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论王夫之“理在气中”的哲学思想
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作者 刘纪璐 苏晓冰 《思想与文化》 CSSCI 2014年第2期250-277,共28页
王夫之拒斥了朱熹那种将理气分别开来、归入不同的本体论体系,且以理为超越的做法,而将'理'与'气'这两个本体论范畴整合了起来。在前王夫之的时代,人们通常将'气'看做一种盲目力量,需要'理'之规范的。... 王夫之拒斥了朱熹那种将理气分别开来、归入不同的本体论体系,且以理为超越的做法,而将'理'与'气'这两个本体论范畴整合了起来。在前王夫之的时代,人们通常将'气'看做一种盲目力量,需要'理'之规范的。但对王夫之而言,理内在于气,气是理的本体论基础,是理的显现与完成。但这并不意味着,王夫之是持'气一元论'的,实际上,王夫之的一元论毋宁说是'理一气一元论',理与气是两者互为体用的。这种'理在气中'的思想奠定了王夫之哲学的基础,他的'道器合一'的思想、'性日生日成'的人性论思想,以及'理在欲中'的道德哲学思想都是建立在这一基础之上的。 展开更多
关键词 在气 理-一元论
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应用络病学理论抗运动性疲劳 被引量:3
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作者 喻治达 沈丹丹 《辽宁中医杂志》 CAS 2014年第2期351-352,共2页
运动性疲劳"劳则气耗","久则血伤而入络";病初在气,久病入络是络病学重要学术观点和发病观。运动性疲劳初病在气,主要为运动功能障碍和湿浊代谢邪毒物质瘀滞。治宜利湿化浊祛邪以宣通气机;运动性疲劳久病入络,主要... 运动性疲劳"劳则气耗","久则血伤而入络";病初在气,久病入络是络病学重要学术观点和发病观。运动性疲劳初病在气,主要为运动功能障碍和湿浊代谢邪毒物质瘀滞。治宜利湿化浊祛邪以宣通气机;运动性疲劳久病入络,主要为阳气耗损,脾肾损伤,运动原始动力不足,治宜温补脾肾阳气以宣通经络。无论内服还是外治都紧扣经络、气机、病邪等关系施治,获得抗运动性疲劳良好效果。 展开更多
关键词 络病学 初病在气 久病入络 运动性疲劳
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理学思维下吴澄的文艺本体论与文道观 被引量:1
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作者 杨万里 《中原文化研究》 2023年第5期120-128,共9页
关于吴澄的文艺本体论问题学界已有不少论述,但就目前的主流研究来看似乎仍值得商榷。鉴于其在文气批评方面的理论成就,大多数学者将其视为气本论者。其实不然,我们应以吴澄的理学思维来理解其文艺观念。从万物构成的角度来说,“理在气... 关于吴澄的文艺本体论问题学界已有不少论述,但就目前的主流研究来看似乎仍值得商榷。鉴于其在文气批评方面的理论成就,大多数学者将其视为气本论者。其实不然,我们应以吴澄的理学思维来理解其文艺观念。从万物构成的角度来说,“理在气中”是其哲学本体观的概括表达,准确理解应是气为本原而理为本体。正是基于此一理学命题,他提出了“理主气辅”的著名文论观点,其中作为主宰的“理”依然是比“气”更为重要的一个范畴。唯有如此,作家才可通过积学明理变化气质,从而突破先天才气之局限和外界不良风气之侵袭,这也为其文艺复古理想提供了学理依据。“理主气辅”之中亦蕴含着文道贯一之思想,因此他主张为文当先闻道,文儒如此,释道亦然。与前辈理学家相比,吴澄文道观念的推导逻辑和阐释边界皆有自己的特色,对其文艺本体论及文道观的探讨启发我们,研究中国文论须遵循中国之“道”。 展开更多
关键词 吴澄 理主 在气 本体论 文道观
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评叶天士“久病入络”说 被引量:5
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作者 李景宏 《中医临床研究》 2015年第17期33-34,共2页
叶天士"久病入络"说将络病分为两个性质完全不同的阶段,既不符合中医关于气血辨证关系的理论,又可能使医者失去在临床上治疗严重危害人类健康的心脑血管病、糖尿病、癌症等于"未病"状态时的机会。
关键词 初病在气 久病入络 虚血瘀 活血 代谢综合征
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Bio-methanol from Bio-oil Reforming Syngas Using Dual-reactor
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作者 叶同奇 颜世志 +3 位作者 徐勇 仇松柏 刘勇 李全新 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第4期457-463,I0004,共8页
A dual-reactor, assembled with the on-line syngas conditioning and methanol synthesis, was successfully applied for high efficient conversion of rich CO2 bio-oil derived syngas to bio-methanol. In the forepart catalys... A dual-reactor, assembled with the on-line syngas conditioning and methanol synthesis, was successfully applied for high efficient conversion of rich CO2 bio-oil derived syngas to bio-methanol. In the forepart catalyst bed reactor, the catalytic conversion can effectively adjust the rich-CO2 crude bio-syngas into the CO-containing bio-syngas using the CuZnA1Zr catalyst. After the on-line syngas conditioning at 450℃, the CO2/CO ratio in the blo- syngas significantly decreased from 6.3 to 1.2. In the rearward catalyst bed reactor, the conversion of the conditioned bio-syngas to bio-methanol shows the maximum yield about 1.21 kg/(kgcatarh) MeOH with a methanol selectivity of 97.9% at 260 ~C and 5.05 MPa using conventional CuZnA1 catalyst, which is close to the level typically obtained in the conventional methanol synthesis process using natural gas. The influences of temperature, pressure and space velocity on the bio-methanol synthesis were also investigated in detail. 展开更多
关键词 Bio-methanol Bio-syngas CuZnA1Zr catalyst On-line syngas conditioning
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In-situ measurement and distribution of flue gas mercury for a utility PC boiler system 被引量:3
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作者 段钰锋 Cao Yan +3 位作者 Shawn Kellie Kunlei Liu John Riley Weiping Pan 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期53-57,共5页
The in-situ instrumentation technique for measuring mercury and itsspeciation downstream a utility 100 MW pulverized coal (PC) fired boiler system was developed andconducted by the use of the Ontario hydro method (OHM... The in-situ instrumentation technique for measuring mercury and itsspeciation downstream a utility 100 MW pulverized coal (PC) fired boiler system was developed andconducted by the use of the Ontario hydro method (OHM) consistent with American standard test methodtogether with the semi-continuous emissions monitoring (SCEM) system as well as a mobile laboratoryfor mercury monitoring. The mercury and its speciation concentrations including participate mercuryat three locations of before air preheater, before electrostatic precipitator (ESP) and after ESPwere measured using the OHM and SCEM methods under normal operation conditions of the boiler systemas a result of firing a bituminous coal. The vapor-phase total mercury Hg(VT) concentration declinedwith the decrease of flue gas temperature because of mercury species transformation from oxidizedmercury to particulate mercury as the flue gas moved downstream from the air preheater to the ESPand after the ESP. A good agreement for Hg°, Hg^(2+) and Hg( VT) was obtained between the twomethods in the ash-free area. But in the dense particle-laden flue gas area, there appeared to be abig bias for mercury speciation owing to dust cake formed in the filter of OHM sampling probe. Theparticulateaffinity to the flue gas mercury and the impacts of sampling condition to accuracy ofmeasure were discussed. 展开更多
关键词 coal fired flue gas mercury speciation in-situ measurement Ontario hydromethod (OHM) semi-continuous emissions monitoring (SCEM)
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辽宁省各市用TSP中流量采样器与大流量采样器对比测试实验研究
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作者 吕京全 杨镇 《环境科技(辽宁)》 1996年第1期18-25,共8页
关键词 在气监测 总悬浮微粒 取样器 测试
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Climate Changes in Northeastern China During Last Four Decades 被引量:11
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作者 ZHAO Dongsheng ZHENG Du +1 位作者 WU Shaohong WU Zhengfang 《Chinese Geographical Science》 SCIE CSCD 2007年第4期317-324,共8页
The northeastern China is a sensitive region of climate change, whose detailed trend of climate changes is highly interesting. In this study, this kind of variation trend was analyzed. Potential evapotranspiration (PE... The northeastern China is a sensitive region of climate change, whose detailed trend of climate changes is highly interesting. In this study, this kind of variation trend was analyzed. Potential evapotranspiration (PE) and moisture index (MI) were modeled by using Thornthwaite scheme based on the observation data of 1961-2004 from 94 meteorological stations. To describe the climate fluctuation in the northeastern China in 1961-2004, the linear regression method was used to analyze the variation trends of mean annual temperature, mean annual precipitation, PE and MI. Mann-Kendall method was used to test the significant difference. The results show a general increasing tendency in mean annual temperature, mean annual precipitation, PE and MI. However increasing tendency was more significant in mean annual temperature and PE than in mean annual precipitation and MI. Analysis of seasonal climate variation indicates that there showed positive trends in winter and in spring, while the positive trend was more significant in winter than in spring. Furthermore, the relations between climate changes and geographical factors were analyzed, the results show that both climate factors and their interannual variability were correlated to latitude, longitude and altitude, suggesting that latitude is the most climate factor affecting climate changes, followed by altitude and longitude. 展开更多
关键词 climate changes potential evapotranspiration moisture index northeastern China
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380 CASES OF BRONCHIECTASIS WITH HEMOPTYSIS TREATED BY POINT-INJECTION 被引量:1
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作者 王伟 宣丽华 傅洁美 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1999年第2期105-107,共3页
Hemoptysis,especially the massivehemoptysis caused by bronchiectasis is acommon,but emergent and critical diseases inclinic.Injection of Herba Houttuyniae extractinto Kongzui(LU 6)was performed to treathemoptysis acco... Hemoptysis,especially the massivehemoptysis caused by bronchiectasis is acommon,but emergent and critical diseases inclinic.Injection of Herba Houttuyniae extractinto Kongzui(LU 6)was performed to treathemoptysis according to the theory oftraditional Chinese medicine and the 展开更多
关键词 Acupuncture Points ADULT Aged Aged 80 and over BRONCHIECTASIS Drugs Chinese Herbal FEMALE HEMOPTYSIS Humans INJECTIONS Male Middle Aged
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Modeling the Flow Regime Near the Source in Underwater Gas Releases 被引量:2
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作者 Lakshitha T. Premathilake Poojitha D. Yapa +1 位作者 Indrajith D. Nissanka Pubudu Kumarage 《Journal of Marine Science and Application》 CSCD 2016年第4期433-441,共9页
Recent progress in calculating gas bubble sizes in a plume, based on phenomenological approaches using the release conditions is a significant improvement to make the gas plume models self-reliant. Such calculations r... Recent progress in calculating gas bubble sizes in a plume, based on phenomenological approaches using the release conditions is a significant improvement to make the gas plume models self-reliant. Such calculations require details of conditions Near the Source of Plume (NSP); (i.e. the plume/jet velocity and radius near the source), which inspired the present work. Determining NSP conditions for gas plumes are far more complex than that for oil plumes due to the substantial density difference between gas and water. To calculate NSP conditions, modeling the early stage of the plume is important. A novel method of modeling the early stage of an underwater gas release is presented here. Major impact of the present work is to define the correct NSP conditions for underwater gas releases, which is not possible with available methods as those techniques are not based on the physics of flow region near the source of the plume/jet. We introduce super Gaussian profiles to model the density and velocity variations of the early stages of plume, coupled with the laws of fluid mechanics to define profile parameters. This new approach, models the velocity profile variation from near uniform, across the section at the release point to Gaussian some distance away. The comparisons show that experimental data agrees well with the computations. 展开更多
关键词 underwater gas releases bubble plumes near source conditions plumes/jets oil and gas spill models
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DIAGNOSTIC ANALYSIS OF THE RE-INTENSIFICATION OF HIGOS IN SOUTHERN CHINA AFTER LANDFALL 被引量:1
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作者 卢山 吴乃庚 《Journal of Tropical Meteorology》 SCIE 2010年第2期181-188,共8页
The NCEP Global Data Assimilation System analysis of grid data, satellite products of Naval Research Laboratory, conventional meteorological data and observations of automatic weather stations in Guangdong province we... The NCEP Global Data Assimilation System analysis of grid data, satellite products of Naval Research Laboratory, conventional meteorological data and observations of automatic weather stations in Guangdong province were used together with environmental conditions, atmospheric circulation, and physical characteristics to diagnose the cause and mechanism of the intensification of tropical cyclone Higos in Southern China. The results showed that favorable environmental conditions of high temperature, humidity of the underlying surface, strong upper divergence, weak vertical wind shear, and the persistence of a southwest jet stream beside the southern Higos were the necessary ingredients that contributed to the maintenance of intensity and re-intensification of Higos. The sinking intrusion of cold air from the lower troposphere was the critical condition for its intensification over land. The fxontal genesis caused by weak cold air increased the lower tropospheric convergence and updraft, and the condensation latent heat released by heavy rains promoted convergence. From this positive feedback process, Higos obtained an increasing of positive vorticity and re-intensified over land. The re-intensification was due not only to the build-up of wind and the reduction of pressure but also to the simultaneous warm-up of its warm core. 展开更多
关键词 Higos intensification over land cold air warm core
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Novel Optical Fiber Gas Sensor for On-line Measurement of Methane
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作者 WANGShu-tao CHERen-sheng +1 位作者 LIUJin WANGYu-tian 《Semiconductor Photonics and Technology》 CAS 2004年第2期141-144,共4页
Based on analysis of near infrared spectral absorption of methane,absorption type optical fiber methane gas sensor with high sensitivity using DFB LD as a source is demonstrated. Light source modulation harmonic measu... Based on analysis of near infrared spectral absorption of methane,absorption type optical fiber methane gas sensor with high sensitivity using DFB LD as a source is demonstrated. Light source modulation harmonic measurement is presented in this paper. In order to eliminate the noise, the ratio of the fundamental and second-harmonic signals is used. The mathematical model of gas concentration harmonic measurement is built up.The detection result of methane concentration is also shown. Experiments have proved a sensitivity of 28×10-6. 展开更多
关键词 Gas sensor METHANE MODULATION Harmonic measurement
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STUDY OF DOUBLE RAIN BANDS IN A PERSISTENT RAINSTORM OVER SOUTH CHINA 被引量:2
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作者 丁治英 刘彩虹 +3 位作者 常越 沈新勇 何金海 徐海明 《Journal of Tropical Meteorology》 SCIE 2010年第4期380-389,共10页
Using the U.S. National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis data at 1°× 1° o resolution, analysis is performed on a persistent heavy rainfall event w... Using the U.S. National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis data at 1°× 1° o resolution, analysis is performed on a persistent heavy rainfall event with two rain bands to the south of the Yangtze River during 17-22 June 2005. The northern rain band was related to the atmospheric mass adjustment of cold front precipitation and the associated ageostrophic feature to the rear right of subtropical westerly jets, while the southern counterpart formed under the joint influence of easterly/westerly jets and the South Asian high (SAH). The ageostrophic wind field to the rear right of the easterly jet center gives rise to an anti-circulation that favors the genesis of the southern belt. The feature ofdu/dt 〈0 around the SAH ridge line and to the rear right of the easterly jet streak results in a strong v - vg〈O field in the vicinity of the rain region as well as to its south. When westerly jets move southward, an intense v Vg〉0 feature appears to the north of the rain region, i.e., behind the center of the westerly jets. The associated mass adjustment leads to vigorous divergence over the rain region, which is responsible for the strong precipitation from the warm sector of the front. Also, a θe front at the middle level of the southern rain band and the cold front favor the release of instable energy to enhance the rainstorm. The southern and northern fronts approach each other and the two rain belts merge into one. 展开更多
关键词 easterly/westerly upper-air jets warm-region rainstorm middle-level front mass adjustment
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Influence of The Belt and Road Initiative on Oil and Gas Infrastructure 被引量:1
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作者 Jiang Xinmin Li Mingguang Sun Ruihao 《China Oil & Gas》 CAS 2016年第2期23-29,共7页
China has proposed the "Belt and Road Initiative (B&R)" in 2013. One its core strategies is international oil/gas cooperation. This paper addresses the status quo of cooperation on oil/gas infrastructure with co... China has proposed the "Belt and Road Initiative (B&R)" in 2013. One its core strategies is international oil/gas cooperation. This paper addresses the status quo of cooperation on oil/gas infrastructure with countries along the line of "B&R', anticipahs the cooperatiorl prospect. On this basis, the author analyzes China's advantages and cooperation basis in this domain, conceives the practical way of cooperation on oil/gas infrastructure with countries along the line of "B&R'. This paper also elaborates on tlre potential risks, risk evaluation criteria and risk corr trol in oil/gas infrastructu re cooperation with countries tries along tire line of "B&R". 展开更多
关键词 Belt and Road Initiative Oil/gas infrastructure Oil/gas international cooperation Market risk COUNTERMEASURES
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On-Line Pyrolysis-Liquid Chromatography of (Meth-) Acrylic Acid in Waterborne Polymers Using Cryogenic Injection
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作者 Aschwin van der Horst Jaqueline Slaakweg Karen Huiskes Yannic van Hooijdonk Afke Kroes 《Journal of Chemistry and Chemical Engineering》 2014年第7期668-675,共8页
Pyrolysis gas chromatography is not a comprehensive analysis method for the determination of acrylics. Polar acrylic monomers show low abundance by gas chromatography. Because of this, a home-made pyrolysis liquid chr... Pyrolysis gas chromatography is not a comprehensive analysis method for the determination of acrylics. Polar acrylic monomers show low abundance by gas chromatography. Because of this, a home-made pyrolysis liquid chromatographic injector by means of cryogenic-focussing is developed to determine the presence and concentration of hydroxyl and carboxyl functional monomers present in water- and solvent-borne acrylics. We have shown the prove-of-principle of using cryogenic-focussing for UPLC (pyrolysis-ultra-performance liquid chromatography) injection. 展开更多
关键词 On-line pyrolysis-UPLC acrylic acid methacrylic acid cryogenic injection.
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Gas Turbine Operation Offshore: Online Compressor Wash Operational Experience
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作者 StianMadsen Lars E. Bakken 《Journal of Mechanics Engineering and Automation》 2014年第12期945-959,共15页
Online compressor wash for six GE LM2500PE engines at a Statoil North Sea offshore field is analyzed. Three engines are generator drivers whilst three engines are compressor drivers. Two of the compressor drive engine... Online compressor wash for six GE LM2500PE engines at a Statoil North Sea offshore field is analyzed. Three engines are generator drivers whilst three engines are compressor drivers. Two of the compressor drive engines are running at peak load (T5.4-control), hence production rate is limited by the available power from these engines. All the six engines analyzed run continuously without redundancy, hence gas turbine uptime is critical for the field's production and economy. The performance and operational experience with on-line wash at different water-to-air ratios and engine loads, as well as economy potentials related to successful on-line wash are given. This work is based on long-term operation with on-line wash, where operational data are collected and performance analyzed, over a 4-5 year period. All engines are operated with four-month intervals between maintenance stops, where off-line crank-wash is performed as well as other necessary maintenance and repairs. On-line wash is performed daily between the maintenance stops at full load (i.e., normal operating load for the subject engine). To keep the engine as clean as possible and reduce degradation between maintenance stops, both an effective on-line water wash system as well as effective air intake filter system, are critical factors. The overall target is to maintain high engine performance, and extend the interval between maintenance stops through effective on-line wash. It is of vital importance to understand the gas turbine performance deterioration. The trending of its deviation from the engine baseline facilitates load-independent monitoring of the gas turbine's condition. Engine response to water injection at different loads and water-to-air ratios, as well as engine response to compressor deterioration is documented and analyzed. Instrument resolution and repeatability are key factors required in order to obtain reliable performance analysis results. Offshore instrumentation on older installations is often limited to the necessary instruments for machine control/protection, and additional instruments for effective performance monitoring and analysis are often missing or, if installed, have less accuracy. As a result of these analyses, a set of monitoring parameters is proposed for effective diagnosis of compressor degradation. Avenues for further research and development are proposed in order to further increase the understanding of the deterioration mechanisms and the gas turbine performance and response. 展开更多
关键词 Gas turbine performance water wash inlet air filter system.
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Effect of Cropland Occupation and Supplement on Light-temperature Potential Productivity in China from 2000 to 2008 被引量:7
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作者 YANG Xiaohuan CHENG Chuanzhou LI Yuejiao 《Chinese Geographical Science》 SCIE CSCD 2010年第6期536-544,共9页
There are more people but less land in China,so food safety has always been a most important issue government concerned.With continuous population increase,economic development and environment protection,cropland occu... There are more people but less land in China,so food safety has always been a most important issue government concerned.With continuous population increase,economic development and environment protection,cropland occupation and supplement are unavoidable.It not only leads to the variation of cropland area,but also makes the light-temperature potential productivity per unit area different due to regional climate differentiation,therefore impacts the total potential productivity and food output eventually.So,it is necessary to analyze the climate differentiation between occupation and supplement cropland areas and to study its impact on total potential productivity,which is significant to reasonably develop natural resources and instruct agricultural arrangement.This study firstly discussed the variation and distribution of occupation and supplement croplands in China from 2000 to 2008,then analyzed the climate differentiation between occupation and supplement cropland areas and its effect on light-temperature potential productivity.The results demonstrate:1) From 2000 to 2008,the cropland variation presented occupation in the south and supplement in the north,but overall decreased.Supplement cropland was mainly from ecological reclamation(77.78%) and was mainly distributed in Northeast China and Northwest China with poor climatic and natural conditions.Occupation cropland was mainly used for construction(52.88%) and ecological restoration(44.78%) purposes,and was mainly distributed in the Huang-Huai-Hai Plain,and the middle and lower reaches of the Changjiang(Yangtze) River with better climatic and natural conditions.2) The climate conditions were quite different in supplement and occupation cropland areas.The annual precipitation,annual accumulated temperature and average annual temperature were lower in the supplement cropland area,and its average po-tential productivity per unit was only 62% of occupation cropland area,which was the main reason for the decrease of total potential productivity.3) Cropland occupation and supplement led to the variation of total potential productivity and its spatial distribution.The productivity decreased in the south and increased in the north,but had a net loss of 4.38315×107 t in the whole country.The increase of cropland area was at the cost of reclaiming natural forest and grassland resources,and destroying natural ecological environment,while the decrease of cropland area was mainly due to a lot of cropland occupied by urban-rural construction,which threatened the sustainable use of cropland resources. 展开更多
关键词 CROPLAND cropland occupation cropland supplement climate condition light-temperature potential productivity China
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The Potentially Dangerous Asteroid (99942) Apophis
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作者 Ireneusz Wlodarczyk 《Journal of Earth Science and Engineering》 2014年第6期385-388,共4页
This paper computed the newest impact solutions of the potentially dangerous asteroid (99942) Apophis based on 4,138 optical observations from March 15.10789 UTC (Universal Time Coordinated), 2004 to February 28.0... This paper computed the newest impact solutions of the potentially dangerous asteroid (99942) Apophis based on 4,138 optical observations from March 15.10789 UTC (Universal Time Coordinated), 2004 to February 28.089569 UTC, 2014 and 20 radar observations from January 27, 2005 through March 15, 2013, as of June 20, 2014. Using the freely available the OrbFit software Package, this paper followed its orbit forward in the searching for close approaches with the Earth and possible impacts up to year 2116. With the different A2 non-gravitational parameter in the motion of the asteroid (99942) Apophis, this paper computed possible impact solutions using the JPL DE405 (Jet Propulsion Laboratory Development Ephemeris) and 25 additional massive perturbed asteroids. Additionally, this paper used weighing and selection methods adopted in the OrbFit software as prepared by the NEODyS (Near Earth Objects--Dynamical Side) Team. Moreover, this paper used method of computing the orbit of Apophis taking into account star catalog debiasing and an error model with assumed astrometric errors RMS (root mean square), deduced from the observational material of the given observatories. JPL's Sentry and NEODyS's CLOMMON2, two automatic monitoring systems routinely scanning for possible impacts in the next hundred years. Only for several dangerous asteroids presented results are computed with the non-gravitational parameters. This paper detected possible impacts of the asteroid (99942) Apophis only with the non-gravitational parameter, A2 〉 0. It was appeared that impacts in 2068, 2087, 2105 and in 2111 were possible only when Apophis rotated in prograde direction. 展开更多
关键词 ASTROMETRY minor planets individual asteroids Apophis (99942).
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