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有关“水星”的几道题
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作者 应周武 田志光 《中学物理》 2004年第12期50-50,共1页
关键词 “水星” 解题思路 解题方法 中学物理 密度 线速度
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民用飞机设计参考机种之一——“水星”双发涡扇短程运输机
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作者 汇中 《民用飞机设计与研究》 2003年第3期23-26,共4页
“水星”是一架120/162座双发涡扇短程运输机,航程在185~2,084公里,供八十年代短程航线使用。它以法国达索公司为主,意大利Aeritalia公司、西班牙CASA公司和比利时SABCA公司的参与共同研制而成。
关键词 机种 民用飞机 设计 “水星” 双发涡扇短程运输机 航程
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“身历其境”出新版 “水星”名演放光芒
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作者 王士昭 《音响世界》 2004年第10期69-71,共3页
无论你是一个古典音乐迷,还是一个唱片收藏家与发烧友,不知道“MERCURY”这个唱片厂牌是绝对不可能的!
关键词 唱片 古典音乐 “水星” SACD多声道系统 录音技术 “单点录音”
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“水星”牌保水剂对甜瓜效果试验总结
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作者 赛提汗.卡得尔 娜海丽汗.吾甫尔 《现代园艺》 2016年第9期16-17,共2页
在大田甜瓜上进行"水星"牌高活性生物营养保水剂使用试验,试验结果表明,使用保水剂的甜瓜产量比对照高,含水量也多,效果较好。
关键词 “水星”牌保水剂 大田甜瓜 比较试验
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彩色茧品种“水星1号”一代杂交种繁育初报 被引量:1
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作者 金杏丽 丁农 +4 位作者 谷丽群 黄林生 蔡永良 尉贤鑫 杨民杰 《蚕桑通报》 2021年第2期30-32,共3页
本文对彩色茧品种“水星1号”的一代杂交种繁育进行了对比试验,分析了繁育过程中出现的一些问题,阐述了下一步推广和应用的具体做法。
关键词 彩色茧“水星1号” 一代杂交种 繁育
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水星
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《世界汽车》 2003年第3期50-50,共1页
关键词 “水星·黑豹”家庭型轿车 “水星·登山家”运动型多功能车 汽车设计 技术参数 装备配置 车型
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台“水星计划”秘闻——购买“海狮”、“海豹”潜艇计划
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作者 路开通 《当代海军》 2005年第6期22-25,共4页
1958年,美国太空总署开始进行“水星计划”。这是美国第一个载人太空计划,在美国太空发展史上是个重要的里程碑。有趣的是,台湾也有个“水星计划”,只不过美国的“水星谋划”是探索外太空的奥秘,而台湾的“水星计划”则是组建内太... 1958年,美国太空总署开始进行“水星计划”。这是美国第一个载人太空计划,在美国太空发展史上是个重要的里程碑。有趣的是,台湾也有个“水星计划”,只不过美国的“水星谋划”是探索外太空的奥秘,而台湾的“水星计划”则是组建内太空战力,即由台湾海军执行的“海狮”、“海豹”两艘潜艇接收计划,这也是台海军建构潜艇兵力的第一步。时隔多年,本文首次将两艇接收内幕公布于众。 展开更多
关键词 台湾省 “水星计划” 潜艇接收 作战任务
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现代电子侦察卫星的应用与发展 被引量:5
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作者 陈茂良 徐捷 《国际太空》 2001年第10期16-18,共3页
关键词 电子侦察卫星 作战应用 “水星”卫星 发展动向 现状分析
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Discovery of a geomorphological analog to Martian araneiforms in the Qaidam Basin, Tibetan Plateau
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作者 Shengxing Zhang Yiliang Li Wei Leng 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第5期1-9,I0006,共10页
Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars.A gas erosion process driven by the seasonal sublimation of CO_(2) ice was proposed as an explanation for their for... Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars.A gas erosion process driven by the seasonal sublimation of CO_(2) ice was proposed as an explanation for their formation,which cannot occur on Earth due to the high climatic temperature.In this study,we propose an alternative mechanism that attrib-utes the araneiform formation to the erosion of upwelling salt water from the subsurface,relying on the identification of the first terrestrial analog found in a playa of the Qaidam Basin on the northern Tibetan Plateau.Morphological analysis indicates that the structures in the Qaidam Basin have fractal features comparable to araneiforms on Mars.A numerical model is developed to investigate the araneiform formation driven by the water-diffusion mechanism.The simulation res-ults indicate that the water-diffusion process,under varying ground conditions,may be responsible for the diverse aranei-form morphologies observed on both Earth and Mars.Our numerical simulations also demonstrate that the orientations of the saltwater diffusion networks are controlled by pre-existing polygonal cracks,which is consistent with observations of araneiforms on Mars and Earth.Our study thus suggests that a saltwater-related origin of the araneiform is possible and has significant implications for water searches on Mars. 展开更多
关键词 araneiform landform subsurface water Qaidam Basin Mars analog fractal simulations
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五月大事记
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《国防科技》 2004年第5期84-84,共1页
关键词 侦察机 气球 载人飞船 “水星” 北极探险
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Three New Species of Actina (Diptera: Stratiomyidae) from China 被引量:1
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作者 于姗姗 崔维娜 杨定 《Entomotaxonomia》 CSCD 北大核心 2009年第4期296-300,共5页
Three new species of Actina from China are described as follows: Actina bimaculata, sp. nov., A. trimaculata, sp. nov. and A. unimaculata, sp. nov. Their relationships with the relative species are discussed. The typ... Three new species of Actina from China are described as follows: Actina bimaculata, sp. nov., A. trimaculata, sp. nov. and A. unimaculata, sp. nov. Their relationships with the relative species are discussed. The type specimens are deposited in the Entomological Museum of China Agricultural University, Beijing (CAU). 展开更多
关键词 DIPTERA STRATIOMYIDAE Actina new species China
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Mapping of S-b Locus for F_1 Pollen Sterility in Cultivated Rice Using PCR Based Markers 被引量:13
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作者 李文涛 曾瑞珍 +1 位作者 张泽民 张桂权 《Acta Botanica Sinica》 CSCD 2002年第4期463-467,共5页
In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its nea... In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its near-isogenic line TIST2 carrying S-b(i)/S-b(i) were used to develop the mapping population. One hundred and fifty-eight microsatellite markers were selected to survey T65 and TISL2. RM13 on chromosome 5 was found to be polymorphic between them. Cosegregation indicated that RM13 was closely linked with locus S-b. Eleven RFLP markers were selected on the corresponding region from the genetic map of Rice Genome Research Program (RGP) of Japan to convert into sequence-tagged site (STS) markers. Amplicon length polymorphism (ALP) was carried out, but none of them was found to be polymorphic between T65 and TISL2. Then PCR-based RFLP (PBR) was done using six 4-nucleotide recognizing restriction endonucleases. Polymorphism was detected when PCR products of R830STS and R2213SSTS were digested with Taq I. Genetic analysis indicated that the distance between locus S-b and markers, R830STS, RM13 and R2213SSTS were 3.3 cM (centi-Morgan), 5.2 cM and 5.5 cM, respectively. These PCR-based markers could be directly used in marker-assisted selection. The technical system combining genetic mapping and PCR-based marker-assisted selection will facilitate the development of molecular breeding. 展开更多
关键词 F-1 pollen sterility genetic mapping MICROSATELLITE sequence-tagged site (STS) RICE
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Fine Mapping of the Blast Resistance Gene P/75, Linked to Pii, on Rice Chromosome 9 被引量:17
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作者 潘庆华 胡珍娣 +1 位作者 谷坂隆俊 王玲 《Acta Botanica Sinica》 CSCD 2003年第7期871-877,共7页
The gene Pi15 for resistance of rice to Magnaporthe grisea was previously identified as being linked to the gene Pii. However, there is a debate on the chromosomal position of the Pii gene, because it was originally m... The gene Pi15 for resistance of rice to Magnaporthe grisea was previously identified as being linked to the gene Pii. However, there is a debate on the chromosomal position of the Pii gene, because it was originally mapped on chromosome 6, but recent work showed it might be located on chromosome 9. To determine the chromosomal location of the Pi15 gene, a linkage analysis using molecular markers was performed in a F2 mapping population consisting of 15 resistant and 141 susceptible plants through bulked-segregant analysis (BSA) in combination with recessive-class analysis (RCA). Out of 20 microsatellite markers mapped on chromosomes 6 and 9 tested, only one marker, RM316 on chromosome 9, was found to have a linkage with the Pi15 gene with a recombination frequency of (19.1 ±3.7)%. To confirm this finding, four sequence-tagged site (STS) markers mapped on chromosome 9 were tested. The results suggested that marker G103 was linked to the Pi15 gene with a recombination frequency of (5.7±2.1)%. To find marker(s) more closely linked to the Pi15 gene, random amplified polymorphic DNA (RAPD) analysis was performed. Out of 1 000 primers tested, three RAPD markers, BAPi15486, BAPi15782 and BAPil5844 were found to tightly flank the Pi15 gene with recombination frequencies of 0.35%, 0.35% and 1.1%, respectively. These three RAPD markers should be viewed as the starting points for marker-aided gene pyramiding and cloning. A new gene cluster of rice blast resistance on chromosome 9 was also discussed. 展开更多
关键词 bulked-segregant analysis (BSA) MICROSATELLITE rice (Oryza sativa) Magnaporthe grisea RAPD recessive-class analysis (RCA) sequencetagged site (STS)
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Mercury speciation and removal across full-scale wet FGD systems at coal-fired power plants 被引量:7
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作者 WU Cheng-li CAO Yan +3 位作者 DONG Zhong-bing CHENG Chin-min LI Han-xu PAN Wei-ping 《Journal of Coal Science & Engineering(China)》 2010年第1期82-87,共6页
The Ontario Hydro Method (OHM) recommended by the United States Environmental Protection Agency (EPA) was used to determine mercury speciation in the combustion flue gas across wet FGD systems. Four coal-fired uni... The Ontario Hydro Method (OHM) recommended by the United States Environmental Protection Agency (EPA) was used to determine mercury speciation in the combustion flue gas across wet FGD systems. Four coal-fired units with wet FGD systems were chosen to evaluate mercury speciation and mercury removal efficiencies through these wet FGD systems. Chlorine content in coal had been suggested as a main factor that affects mercury speciation in flue gas. It is shown that the higher the chlorine concentration in coal is, the higher the percentage of oxidized mercury (Hg2+) is removed in wet FGD systems, which can increase overall mercury removal efficiencies through wet FGD systems. The selective catalyst reduction (SCR) system has a function of oxidizing ele- mental mercury (Hg0) to oxidized mercury. A higher percentage of oxidized mercury in the total vapor mercury at the FGD inlet is observed when SCR is in service. Therefore, higher overall mercury removal efficiencies through wet FGD are attained. Because of different wet FGD operating conditions, there are different mercury removal efficiencies in different units. Elemental mercury reemission took place when a fraction of oxidized mercury absorbed in the slurry is reduced to elemental mercury, and Hg2+ is reemitted from stack, which results in decreases in mercury removal efficiencies through wet FGD systems. 展开更多
关键词 wet FGD mercury speciation mercury removal field testing
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Observed Diurnal Cycle of Summer Precipitation over South Asia and East Asia Based on CMORPH and TRMM Satellite Data 被引量:3
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作者 ZHANG Xin-Xin BI Xun-Qiang KONG Xiang-Hui 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第4期201-207,共7页
The characteristics of the summer precipitation diurnal cycle over South Asia and East Asia during 2001–13 are investigated based on the high spatiotemporal resolution estimates of the CPC(Climate Prediction Center) ... The characteristics of the summer precipitation diurnal cycle over South Asia and East Asia during 2001–13 are investigated based on the high spatiotemporal resolution estimates of the CPC(Climate Prediction Center) Morphing(CMORPH) technique. The results show that summer precipitation over South Asia and East Asia possesses a remarkable diurnal cycle, with obvious regional differences. Over the coastal areas, plateau, and high mountains, summer precipitation peaks in the late afternoon; while over low altitude areas, such as valleys, basins, and inshore seas, it peaks during midnight to early morning. In addition to these general features consistent with previous studies, the high resolution CMORPH technique can depict finer regional details, such as the less coherent phase pattern over a few regions. Besides, through comparative analysis of the diurnal cycle strength and precipitation fields, the authors find that for humid areas the summer precipitation diurnal cycle is especially significant over Southeast China, the Sichuan Basin, Hainan Province, Taiwan Province, the Philippines, and Indonesia. And it is relatively weak over the south of Northeast China, central East China, Yunnan Province, the central Indian Peninsula, and most oceanic areas. Comparisons between two satellite datasets—those of the CMORPH and Tropical Rainfall Measuring Mission(TRMM) 3B42 products—are also presented. For summer precipitation and the main diurnal cycle features, the results from both products agree over most regions, except a few areas, e.g., the Tibetan Plateau. 展开更多
关键词 diurnal cycle PRECIPITATION CMORPH TRMM 3B42 South Asia East Asia
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Comparison of CloudSat Cloud Liquid Water Paths in Arctic Summer Using Ground-Based Microwave Radiometer 被引量:3
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作者 LIU Shuang Georg Heygster ZHANG Suping 《Journal of Ocean University of China》 SCIE CAS 2010年第4期333-342,共10页
Arctic clouds strongly influence the regional radiation balance, temperature, melting of sea ice, and freezing of sea water. Despite their importance, there is a lack of systematic and reliabie observations of Arctic ... Arctic clouds strongly influence the regional radiation balance, temperature, melting of sea ice, and freezing of sea water. Despite their importance, there is a lack of systematic and reliabie observations of Arctic clouds. The CloudSat satellite launched in 2006 with a 94GHz Cloud Profiling Radar (CPR) may contribute to close this gap. Here we compare one of the key parameters, the cloud liquid water path (LWP) retrieved from CloudSat observations and from microwave radiometer (MWR) data taken during the ASCOS (Arctic Summer Cloud Ocean Study) cruise of the research vessel Oden from August to September 2008. Over the 45 days of the ASCOS cruise, collocations closer than 3 h and 100 km were found in only 9 d, and collocations closer than 1 h and 30 km in only 2 d. The poor correlations in the scatter plots of the two LWP retrievals can be explained by the patchiness of the cloud cover in these two days (August 5th and September 7th), as confirmed by coincident MODIS (Moderate-resolution Imaging Spectroradiome- ter) images. The averages of Oden-observed LWP values are systematically higher (40-70 g m-2) than the corresponding CloudSat observations (0-50 g m2). These are cases of generally low LWP with presumably small droplets, and may be explained by the little sensitivity of the CPR to small droplets or by the surface clutter. 展开更多
关键词 CLOUDSAT liquid water path ARCTIC microwave radiometer COLLOCATION Oden
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Exploring a broadened operating pH range for norfloxacin removal via simulated solar-light-mediated Bi_2WO_6 process 被引量:5
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作者 Meijuan Chen Yu Huang Wei Chu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第5期673-680,共8页
Semiconductor photocatalysis can be operated over a narrow pH range for wastewater treatment. In this study, a simulated solar-light-mediated bismuth tungstate (SSL/Bi2WO6) process is found to be effective for norflox... Semiconductor photocatalysis can be operated over a narrow pH range for wastewater treatment. In this study, a simulated solar-light-mediated bismuth tungstate (SSL/Bi2WO6) process is found to be effective for norfloxacin degradation over a narrow pH range. To broaden the operating pH range of the SSL/Bi2WO6 process, an NH4+ buffer system and an Fe3+ salt were introduced under extremely basic and acidic pH conditions, respectively. The NH4+ buffer system continuously supplied hydroxyl ions to generate ·OH radicals and prevented acidification of the solution, resulting in improved norfloxacin removal and mineralization removal under alkaline conditions. In contrast, the Fe3+ salt offered an additional homogeneous photo-sensitization pathway. The former treatment assisted in norfloxacin decay and the latter increased the collision frequency between the photo-generated hole and hydroxyl ions. Moreover, the effect of parameters such as pH and Fe3+ dosage was optimized. 展开更多
关键词 Bismuth tungstate Broadened operating pH NORFLOXACIN PHOTOCATALYSIS Water
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Effects of clam size, food type, sediment characteristic, and seawater carbonate chemistry on grazing capacity of Venus clam Cyclina sinensis (Gmelin, 1791) 被引量:2
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作者 林听听 周凯 +3 位作者 刘鑫 来琦芳 张东 施利燕 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第5期1239-1247,共9页
Aquaculture in saline-alkaline water has a major problem: microalgal blooming causes the pH of water to increase dramatically, thereby causing damage to the reared organisms. To solve this problem, we set out to find... Aquaculture in saline-alkaline water has a major problem: microalgal blooming causes the pH of water to increase dramatically, thereby causing damage to the reared organisms. To solve this problem, we set out to find a candidate filter-feeding bivalve species suitable for saline-alkaline water to graze on microalgae and to control the pH. In the current study, we investigated the effect of carbonate alkalinity (CA, 2.5, 10.0, and 20.0 meq/L) and pH (8.0, 8.5, and 9.0) on the grazing capacity (GC) of the clam Cyclina sinensis. Additionally, the effect of clam size (small, medium, and large) and microalgae species (Nannochloropsis oculata, Chaetoceros miielleri, and lsochrysis galbana), and the effect of bottom sediment characteristic (mud, sandy mud, and muddy sand) and thickness (3 and 6 cm) were analyzed as well. The results show that the GC on L galbana was the highest and small size had the maximum GC/W (W: wet weight including body and shells). No significant differences were observed between sediment type and thickness. Regarding CA and pH, a significant decrease in GC by the pH or by their interaction was found. The GC ofC. sinensis was not greatly reduced in the treatments ofpH≤8.5 and CA≤20.0, and also not affected by bottom sediment type, indicating that this clam is capable to manage microalgal concentrations and might be a candidate species for pH reduction in saline-alkaline water ponds. 展开更多
关键词 Venus clam Cyclina sinensis carbonate alkalinity pH grazing capacity saline-alkaline water
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Three new records of deep-water goniasterids (Echinodermata:Asteroidea:Goniasteridae) from China seas
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作者 肖宁 廖玉麟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期1036-1044,共9页
In this paper,three deep-water species of the family Goniasteridae,Ceramaster misakiensis(Goto,1914),Nymphaster arthrocnemis Fisher,1913 and Pontioceramus grandis Fisher,1911,are recorded for the first time from Chine... In this paper,three deep-water species of the family Goniasteridae,Ceramaster misakiensis(Goto,1914),Nymphaster arthrocnemis Fisher,1913 and Pontioceramus grandis Fisher,1911,are recorded for the first time from Chinese waters based on collections deposited in the Marine Biological Museum,Chinese Academy of Sciences.The specimens examined were collected during the period 1956 to 1978 from the East China and South China Seas at depths of 184 to 472 m.Diagnosis,detailed figures,and the geographic distributions are provided.A revised list of Goniasteridae recorded from Chinese waters is proposed. 展开更多
关键词 ECHINODERMATA ASTEROIDEA Valvatida deep-water goniasterids new records China seas
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载人飞船发射简史小记
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《国防科技》 2003年第1期81-81,共1页
1961年4月12日,前苏联发射了世界上第—艘“东方”号载人飞船,开辟了人类载人航天的新纪元。“东方”号是前苏联研制的第一代载人飞船,由球形航天员座舱、仪器舱和反推火箭发动机组成,重约47吨,只能乘坐1名航天员。航天员在座舱内... 1961年4月12日,前苏联发射了世界上第—艘“东方”号载人飞船,开辟了人类载人航天的新纪元。“东方”号是前苏联研制的第一代载人飞船,由球形航天员座舱、仪器舱和反推火箭发动机组成,重约47吨,只能乘坐1名航天员。航天员在座舱内的弹射座椅上着密闭式航天服飞行,最长飞行时间为5天。 展开更多
关键词 “东方”号载人飞船 载人航天 苏联 航天员 “水星6”号飞船 “上升2”号载人飞船 “阿波罗11”号飞船 美国
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