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41.
The genus Riasanites, represented in Central Russia by two successive dimorphic species, is revised. R. swistowianus is found in the basal beds of the rjasanensis Zone. Its descendant R. rjasanensis is also found in this zone, but upwards in the section, including the beds with Surites spasskensis and Externiceras solowaticum. The representatives of Riasanites from the Crimea and Northern Caucasus are assigned to two species, R. crassicostatus and R. maikopensis, respectively. It is suggested that Riasanites evolved from Sub-Mediterranean Himalayatidae, which migrated from the Western Tethys via the Polish Passage into the Central Russian Basin, and from there to Mangyshlak, the Northern Caucasus, and the Crimea.  相似文献   
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稻麦轮作FACE系统平台I.系统结构与控制   总被引:49,自引:4,他引:45  
在稻麦轮作水稻田建立FACE系统 (Free AirCO2 Enrichment) ,即CO2 浓度的控制和监测系统平台 .利用计算机网络系统对平台的CO2 浓度进行监测控制 ,根据大气中的CO2 浓度、风向、风速 ,作物冠层高度的CO2 浓度及昼夜等因素的变化调节CO2 气体的释放速度及方向 ,实现FACE圈的CO2 浓度高于周围大气CO2 浓度 2 0 0 μmol·mol-1.试验表明 ,影响控制精度的主要因素有风速、作物和土壤呼吸作用和扩散层高度 .经过控制方程参数调整 ,在白天 ,控制精度达到 80 %的时间占总时间的白天达到 83% ,夜晚为6 8% .FACE圈内的CO2 分布基本均匀 .平均CO2 设置浓度白天为 5 5 7mol·mol-1,晚上为 6 0 8mol·mol-1.圈内CO2 浓度分布基本上沿放气管对称分布 ,由边沿向中心逐步降低 .2 0 0 1年水稻生长季节平均控制精度 (TAR)达到白天 1.0 3和晚间 1.0 9.  相似文献   
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生物制药发展状况、方向及相关技术平台   总被引:2,自引:0,他引:2  
自从生物技术应用于医药工业后,生物制药得以迅速发展。生物制药呈现出克隆技术、血管发生、基因治疗、药物基因组学等新的发展方向。基于现阶段基因治疗、基因工程药物、转基因植物、克隆动物、诊断试剂等相关成果和产业,基因组、生物芯片、干细胞、生物信息学、神经科学等相关技术平台的建立和完善将会对生物制药的发展起着重要的作用。  相似文献   
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Summary The Cabo Cope Unit, which outcrops east of Aguilas (Murcia), belongs to the Maláguide tectonic Complex (Betic Internal Zone) and displays stratigraphic characteristics of particular interest, including Triassic bioclastic carbonate beds which are not common in the Maláguide units. Biostratigrafic fossils have been found in these beds and may correlate with Triassic alpine biofacies. Alpine fauna fossils only appeared in those palaeogeographic units of the Internal Zone of the Cordillera referred to as Alpujárride units, while the influence of the Sephardic faunal province is evident in almost all the cordillera. For these reasons it is noteworthy that new alpine fauna fossils have been found in an Internal Zone unit in which relevant fossils rarely appear. The Triassic succession of the unit studied in this paper can be subdivided into two members: a lower one, which is clastic and contains thick gypsum beds, and an upper one, consisting of carbonate rocks. The lower member has been interpreted as a fluvial-coastal deposit. The upper member is interpreted as a sequence of carbonate ramp deposits. This ramp evolved into a shallow platform with tidal flats typical of a coastal zone. The bivalve fossilsDaonella cf.lommeli (Wissmann) and “Posidonia” sp. have been found in the carbonate member, along with the conodontSephardiella mungoensis (Diebel). These fossils are of the Late Ladinian age and have been found only in this outcroup of the Betic Cordillera. The presence of this fossil assemblage, which belongs to the alpine faunal province, indicates a connection during the Late Ladinian between the Tethys sea and this area of the Maláguide palaeogeographic domain. The palaeogeographic location of the Cabo Cope Unit during the Middle Triassic was at the south-easternmost part of the Betic Basin, implying that the connection between the Tethys and the Betic Basin was established in the easternmost domains of the basin.  相似文献   
46.
Recombinant proteins can be produced in a diverse array of plant-based systems, ranging from whole plants growing in the soil to plant suspension cells growing in a fully-defined synthetic medium in a bioreactor. When the recombinant proteins are intended for medical use (plant-derived pharmaceutical proteins, PDPs) they fall under the same regulatory guidelines for manufacturing that cover drugs from all other sources, and when such proteins enter clinical development this includes the requirement for production according to good manufacturing practice (GMP). In principle, the well-characterized GMP regulations that apply to pharmaceutical proteins produced in bacteria and mammalian cells are directly transferrable to plants. In practice, the cell-specific terminology and the requirement for a contained, sterile environment mean that only plant cells in a bioreactor fully meet the original GMP criteria. Significant changes are required to adapt these regulations for proteins produced in whole-plant systems and it is only recently that the first GMP-compliant production processes using plants have been delivered.  相似文献   
47.
Sylvie Crasquin 《Geobios》1984,17(3):341-351
The study of the distribution of Ostracode superfamiliesin the Dinantian of Northern France, Belgium and South Canadian Rockies leads us to establish a new Bairdiacean and Paraparchitacean ecozone. In a confined environment Kloedenellacea become more important. This association is characteristic of carbonate shelf sedimentation in warm climatic conditions. Russian and American bibliography strengthen our conclusions.  相似文献   
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郧县人遗址石核的研究   总被引:4,自引:2,他引:2  
在郧县人遗址中发现的石核占整个遗址石制品总数的26%。虽然数量仅77件,但从石核上可以看出打片以锤击法为主,采用硬锤直接打击。其利用率不高。石核的打片长度基本上只占该台面周长的一半以下,多在台面的一个边打片,剥片面上的石片疤多为单层,有些打下一块石片后就不再继续打片了。  相似文献   
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