25 resultados para Adams, Solomon.
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从1949年以来经过近五十年的发展,超低温保存种质细胞技术已经趋于成熟,特别是在家畜推广良种化的过程中发挥重要作用。对海洋动物种质细胞保存研究的范围主要集中在鲑鳟鱼类和牡蛎等少数几种海洋生物上。本研究结合“国家自然科学基金”研究项目,进行了三种贝类和两种鱼类精子的超低温保存实验,得到了它们在液氮(-196 ℃)条件下的适宜保存条件。栉孔扇贝(Chlamys farreri)冻精解冻后复苏比例、受精率和孵化率最高可达到49.39%、42.06%和12.15睦栉孔扇贝精子超低温保存时发生冷冻伤害的温度范围在-30 ℃~-60 ℃;其低温保存的最适降温速率为20 ℃/min;使用抗冻剂二甲基亚砜(DMSO)的最适浓度为5 ℃,其保存效果优于甘油;样品保存的最佳体积为0.6ml~1ml;解冻精子的最适水温为35 ℃,50 ℃次之,20 ℃最差;用自然海水激活解冻后精子的效果好于低盐度溶液;在0 ℃进行预处理平衡时间不宜太长;在抗冻液中加入蛋黄对保存效果没有改善,并且会对冻精的孵化率有抑制作用;用20 ℃/min和5%DMSO冷冻精子,液氮中保存栉孔扇贝精子55天后其复苏比例达到42.17%。超低温保存紫贻贝(Mytilus galloprovincialis Lamarck)精子,解冻后其复苏比例、受精率和孵化率最高可达到41.63%、69.52%和54.74%。保存紫贻贝精子最适降温速率为5 ℃/min,发生冻伤的温度范围是-20 ℃~-60 ℃;使用抗冻剂DMSO的保存效果好于甘油,且使用抗冻剂DMSO的最适浓度为15%;利用自然海水激活冻精效果好于低盐度或高pH值的溶液;样品体积(在0.2~1ml之间)对保存效果没有影响;采用15%DMSO和5 ℃/min的降温速率处理精子,液氮中保存90天后复苏比例仍达到41.8%。保存菲律宾蛤仔(Ruditapes philippinarum (Adams and Reeve))精子的最适降温速率为5 ℃/min,发生冻伤的温度范围是-30 ℃~-60 ℃;抗冻剂DMSO的保存效果好于甘油,也用DMSO与甘油混合使用,使用抗冻剂DMSO的最适浓度为10%;利用自然海水激活冻精效果好于低盐度或高pH的溶液;样品体积(在0.2%~1.6ml之间)对保存效果有显著影响。冷冻保存后精子复苏比例、受精率和孵化率最高达到40.84%、68.87%和47.17%;以最适降温速率和抗冻剂浓度处理精子,并在液氮中保存36天后冻精复苏比例仍可以达到38.54%。黑鲷(Sparus macrocephalus)精子经过超低温保存后复苏率、存活率最高可以达到61.37%和61.4。保存黑鲷精子时发生冷冻伤害的温度范围是-20 ℃~-60 ℃,适宜的降温速率为20 ℃/min;使用抗冻剂DMSO的适宜浓度为20%;样品体积对保存效果有相关性;利用自然海水激活冻精效果好于低盐度或高pH值的溶液;使用20%DMSO和20 ℃/min降温速率处理,在液氮中保存黑鲷精子66天后解冻,其复苏率和存活率分别为59.81%和58.45%。在液氮中保存真鲷(Pagrosomus major)精子时发生冷冻伤害的温域为-30 ℃~-60 ℃,适宜的降温速率为20 ℃/min;使用抗冻剂DMSO的适宜浓度为20%;采用低盐度或高pH值的溶液激活冻精的效果不如自然海水。真鲷冻精的复苏率和存活率最高可达到50.73%和62.5;以20 ℃/min和20%DMSO处理真鲷精子,保存在液氮中46天后冻精复苏率和存活率为50.63%和61.02%。通过对多种贝类和鱼类精子的超低温保存实验,不仅获得超低温保存基本条件,并且通过显微镜观察结合前人的研究,对产生冻伤的原因和保护的机理提出了一个模式。
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The proposed plan for enrichment of the Sulu Sea, Philippines, a region of rich marine biodiversity, with thousands of tonnes of urea in order to stimulate algal blooms and sequester carbon is flawed for multiple reasons. Urea is preferentially used as a nitrogen source by some cyanobacteria and dinoflagellates, many of which are neutrally or positively buoyant. Biological pumps to the deep sea are classically leaky, and the inefficient burial of new biomass makes the estimation of a net loss of carbon from the atmosphere questionable at best. The potential for growth of toxic dinoflagellates is also high, as many grow well on urea and some even increase their toxicity when grown on urea. Many toxic dinoflagellates form cysts which can settle to the sediment and germinate in subsequent years, forming new blooms even without further fertilization. If large-scale blooms do occur, it is likely that they will contribute to hypoxia in the bottom waters upon decomposition. Lastly, urea production requires fossil fuel usage, further limiting the potential for net carbon sequestration. The environmental and economic impacts are potentially great and need to be rigorously assessed. (C) 2008 Elsevier Ltd. All rights reserved.
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Ninteen species of subfamilies Imbricariinae and Cylindromitrinae, family Mitridae, are recorded from the China's seas. Of which, one genus and six species are recorded for the first time from China's seas, i.e., genus Ziba Adams H and Adams A, Cancilla (Cancilla) carnicolor, Ziba duplilirata, Z. insculpta, Neocancilla circula, Scabricola (Scabricola) desetangsii, Scabricola (Swainsonia) ocellata ocellata.
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The morphology and infraciliature of two ectoparasitic ciliates, Trichodina caecellae n. sp. and T. ruditapicis Xu, Song & Warren, 2000, parasitising the gills of marine molluscs from the Shandong coast of the Yellow Sea, China, were investigated following wet silver nitrate and protargol impregnation. T. caecellae was found on the small marine sand clam Caecella chinensis Deshayes and is distinguished mainly by the acute triangle-like blade, the very delicate central part and the needle-shaped ray. T. ruditapicis was studied based on four populations from three clams: two populations from Ruditapes philippinarum (Adams) and one each from Saxidomus purpuratus (Sowerby) and Solen grandis Dunker. All four populations fell within the range of morphometry and agreed closely in the overall appearance of the adhesive disc. However, variability was found in the denticle structure, especially in populations from different host clams. Our observations suggest that denticle morphology may be more or less variable between and within populations, and that such minor differences should not be overestimated. It should be emphasised that, except for the denticle morphology, the bright granules or circles in the centre of the adhesive disc represent another important feature facilitating the identification of this trichodinid species.
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The composition of the leaf oils from seven populations of J. sabina L., one population of Juniperus sabina var. arenaria (E. H. Wilson) Farjon were examined for their geographic variation. In addition, the leaf oils of J. chinensis L. and J. davurica Pall. were compared to J. sabina. Juniperus sabina var. arenarla, the sand loving juniper, oil was found to be very similar to that of J. davurica, Mongolia, and J. sabina, on sand dunes in Mongolia. This suggests that J. sabina var. arenaria might be conspecific with J. davurica. Farjon's move (2001) of J. sabina var. arenaria out of J. chinensis is supported. Considerable differentiation was found in populations of J. sabina from the Iberian peninsula. Cedrol, citronellol, safrole, trans-sabinyl acetate, terpinen-4-ol and beta-thujone were found to be polymorphic in several populations.
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该文对中国科学院沈阳自动化所研制的水陆两栖蛇形机器人的水下蜿蜒运动进行受力分析并用ADAMS做了动力学仿真。从关节角函数的幅值、频率和体内形成波的个数三个方面对蛇形机器人前进速度的影响进行了仿真,得出以下结论:存在一个最优关节角函数幅值,使得蛇形机器人前进速度达到最大;增加频率和在满足形成蛇形曲线的体内形成波个数的情况下减少形成波的个数会使机器人前进的速度增加。
Resumo:
月球探测车在崎岖不平的月面上行走时,其动态性能的优劣直接影响到车载各种科学仪器设备的正常工作。针对某一六轮摇杆转向架式月球车,利用ADAMS软件建立了其刚柔耦合多体系统动力学模型,并进行了模态分析。结果表明,月球车前六阶固有频率在5.79~19.11Hz之间,模态比较密集,结构比较柔软。该结果可为月球车结构动态设计及振动控制提供依据和参考。
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本文介绍了使用ADAMS软件包在机器人虚拟样机制造中,进行动力学分析的方法及ADAMS动力学分析软件与COSMOS有限元分析软件相结合,在机器人本体(SIASUN-RH6型)设计与研制过程中的应用。
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直角坐标机器人作为一种常用的工业机器人广泛应用于现代工业生产线中,其运动学和动力学特性关系整个生产线性能发挥。虚拟样机技术在复杂机械系统仿真中的成功应用不仅可以提高仿真精度,而且还可以缩短产品设计周期,对于工程实际具有重要的应用价值。通过虚拟样机技术,工程师可以通过机械系统运动仿真,在产品设计阶段发现产品设计中的潜在问题,并快速进行修改,减少了对于物理样机的依赖,这样不仅可以节省成本,缩短产品开发周期,而且还可以提高产品性能,增强产品竞争力。本文结合中科院沈阳自动化研究所现代装备研究设计中心的大型项目“激光拼焊生产线”,对生产线中从国外引进的上下料机器人进行研究分析,设计出一台可以满足“激光拼焊生产线”工业要求的上下料直角坐标机器人,来实现高性能上下料机器人的国产化。以设计出的上下料直角坐标机器人为研究对象,采用虚拟样机技术,以有限元法和多体系统动力学为理论基础,进行上下料直角坐标机器人机构的运动学和动力学分析仿真研究。其中研究了三维实体建模方法以及D-H方法,探讨了利用CAD/CAE软件SOLIDWORKS, ADAMS和ANSYS进行协同虚拟样机的建模、装配、数据共享、有限元静力分析以及刚柔耦合多体动力学仿真技术,研究成果对实际工程的运用具有一定的指导作用。本文主要的研究工作及其成果如下: 1根据工业生产线要求,确定高性能上下料直角坐标机器人总体机构设计方案,设计各个直线运动单元。 2利用CAD软件SOLIDWORKS对上下料直角坐标机器人进行3维实体建模,然后利用D-H方法,建立其运动学方程,最后利用MATLAB工具对运动学进行仿真。 3以有限元方法为基础,利用有限元分析软件ANSYS对上下料直角坐标机器人核心部件Y轴横梁静力分析,最后进行横梁结构优化。 4以多体系统动力学为基础,利用有限元软件ANSYS生成刚柔耦合多体动力学仿真所需的模态中性文件(MNF),同时结合运用ANSYS和ADAMS建立了上下料直角坐标机器人刚柔性耦合多体模型,并进行了动力学分析。
Resumo:
The purpose of this study is to investigate the influence of attention resourse requirement and allocation on implicit memory and explicit memory for object-location associations in driving situation based on Adams theory on the function of implicit knowledge in the Situation Awareness(SA). This study adopted Musen’s implicit learning of object-location associations, sysmemtly manipulated the type and difficuty of the naming task. This research includes three studies and ten experiments. Their aim are separately to explore the influence of attention on implicit and explicit memory for object-loction assocaitons in simple stimulus and the driving situation. And it is needed to confirme the condition and the influencing factors of implicit memory for car-location association in different condition. It is also our aim to explore the feasibility of introduce of implicit learning methods in SA measurement. The results indicted that: ⑴ The influence of attention resourse allocation ,the difficulty of naming task , the deepness of processing on on implicit memory for object-location associations in driving situation are different . the dissociated results support the standpoint that there are two independent knowledge system; ⑵ The type of naming task more influenced the implicit and explicit memory for object-location associations than the difficulty of the naming task. The attention resourse requirement of the different type can not be compared; ⑶ The implicit memory seldom appears in the location naming task resulted from the defiency of processing on object-location association, and not as a results of the overtaxed; ⑷ The reaction time methods in the implicit learning could be used in SA measurement , it is a complementarity of the existing explicit SA measurement. These findings not only contribute to resolve ongoing debates about the process of cognition and mechanism of SA structure, but also have significant practical application in traffic safety.