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A new method is developed to calculate monthly CO emission data using MOZART modeled and MOPITT observed CO data in 2004. New CO emission data were obtained with budget analysis of the processes controlling CO concentration such as surface emission, transport, chemical transform and dry deposition. MOPITT data were used to constrain the model simulation. New CO emission data agree well with Horowitz’s emissions in the spatial distributions. Horowitz’s emissions are found to underes- timate CO emissions significantly in the industrial areas of Asia and North America, where high CO emissions are mainly due to the anthropogenic activities. New CO emissions can better reflect the more recent CO actual emissions than Horowitz’s.  相似文献   

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针对目前的新形势、新要求,探讨科技期刊编辑转型过程中存在的一些主观和客观问题;指出政府部门多出台一些有利于编辑的政策、不断提高编辑人员的自身素质、提高作者对编辑工作的认识及读者的素质,将加快科技期刊编辑从传统编辑人才到新型编辑人才、从编辑匠到编辑家(杂家)的转变.  相似文献   

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Lunt D 《Nature》2010,468(7320):37
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在新疆伊犁地区选定了9块地理位置接近、环境类似、不同龄级的速生杨防护林。每月对林地土壤呼吸、土壤温度进行测定,分析可知:新疆伊犁地区生长季内(5至10月)速生杨防护林土壤呼吸在7、8两个月内最活跃;日变化最大值出现在16:00左右,月变化的最大绝对值和相对值都出现在生长最旺盛的8月。随着林分年龄的增长,土壤呼吸日变化和月变化的相对差值和最大值都有减小的趋势,而且土壤呼吸随土壤温度(地下5 cm)变化呈Power曲线分布。  相似文献   

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VALYI-NAGY T  URI J  SZILAGYI I 《Nature》1954,174(4441):1105-1106
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Druitt TH  Costa F  Deloule E  Dungan M  Scaillet B 《Nature》2012,482(7383):77-80
Caldera-forming volcanic eruptions are low-frequency, high-impact events capable of discharging tens to thousands of cubic kilometres of magma explosively on timescales of hours to days, with devastating effects on local and global scales. Because no such eruption has been monitored during its long build-up phase, the precursor phenomena are not well understood. Geophysical signals obtained during recent episodes of unrest at calderas such as Yellowstone, USA, and Campi Flegrei, Italy, are difficult to interpret, and the conditions necessary for large eruptions are poorly constrained. Here we present a study of pre-eruptive magmatic processes and their timescales using chemically zoned crystals from the 'Minoan' caldera-forming eruption of Santorini volcano, Greece, which occurred in the late 1600s BC. The results provide insights into how rapidly large silicic systems may pass from a quiescent state to one on the edge of eruption. Despite the large volume of erupted magma (40-60 cubic kilometres), and the 18,000-year gestation period between the Minoan eruption and the previous major eruption, most crystals in the Minoan magma record processes that occurred less than about 100 years before the eruption. Recharge of the magma reservoir by large volumes of silicic magma (and some mafic magma) occurred during the century before eruption, and mixing between different silicic magma batches was still taking place during the final months. Final assembly of large silicic magma reservoirs may occur on timescales that are geologically very short by comparison with the preceding repose period, with major growth phases immediately before eruption. These observations have implications for the monitoring of long-dormant, but potentially active, caldera systems.  相似文献   

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《第五频道》期刊围绕“炫与释放激情”的主题,以娱乐的风格报道体育新闻,打造了一本全新的时尚体育期刊,彰显出体育新闻中的娱乐元素在现今体育新闻报道环境中的适应性与丰富性,体现了时尚与体育融合的精彩.  相似文献   

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在介绍重构相空间技术的主要定量指标(关联维数D2和柯尔莫奇诺夫熵)的基础上,以长江上游金沙江流域小黄瓜园站和蔡家村站的月径流时间序列为例详细说明了求取时间序列中的混沌特征数的方法;并且采用主分量分析(PCA分布)方法进一步验证了两个站的径流序列具有混沌特性.得到金沙江流域径流序列的预测年限不应超过7~9个月,为金沙江流域径流预测提供了科学的依据.  相似文献   

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Insulin-proinsulin, a new crystalline complex   总被引:1,自引:0,他引:1  
B W Low  W W Fullerton  L S Rosen 《Nature》1974,248(446):339-340
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A J Charig  A C Milner 《Nature》1986,324(6095):359-361
An extremely large claw bone, some 30 cm long, was found in Wealden (Lower Cretaceous) deposits in a Surrey claypit in January 1983. This led to the discovery the following month of the well-preserved skeleton of a new large theropod dinosaur. Only one other theropod specimen comprising more than a few bones had ever been found in Britain, and that discovery was more than a century ago. Indeed, no large theropod, reasonably complete, had previously been discovered in Lower Cretaceous rocks anywhere in the world. Our study so far suggests that the Surrey dinosaur was a typical large theropod in certain respects, resembling, for example Allosaurus. In several other respects, however, it differs sufficiently from all known dinosaurs to merit designation as the representative of a new species, genus and family.  相似文献   

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设计、合成了新型的以均三嗪为核的八极分子2,4,6-三(对烯丙氧基苯乙烯基)均三嗪;用IR、EA、1H NMR、13CMNR、UV-vis等对其结构进行了表征,测试了TG和UV-vis等性能,对其热稳定性和透明性进行了研究.采用粉末倍频法对其二阶非线性光学性能进行了测试.实验表明:在DMF中该八极分子的最大吸收波长为361 nm,热分解温度为406℃,倍频效应强度为KDP晶体的1.2倍,具有较好的热稳定性和透明性,可用于制备性能优异的非线性光学材料.  相似文献   

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在中国革命、建设和改革过程中,我们党总是能够因应时代发展的需要,将阶段性的任务同党的指导思想统一起来,明确提出具体的奋斗目标。党的十六大提出的“全面建设小康社会”的宏伟纲领,它既表现为一种理论形态,又表现为一个特殊的发展阶段和具体的目标体系,它是三者的有机统一。  相似文献   

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