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131.
132.
在列车结构基本上固定的前提下, 仅利用高铁线路隔离区外单个检波器采集的地震数据来估计高铁的运行速度。通过给出列车经过铁路上一点时该点的受力函数振幅谱与列车运行速度的关系, 提出一种基于速度扫描的列车速度估计方法。首先根据列车结构参数及预设列车运行速度生成一系列受力函数振幅谱, 然后计算各种速度下的受力函数振幅谱与单个检波器所接收到信号振幅谱的互相关函数, 最终选取互相关函数值最大时对应的速度作为列车运行速度的估计值。合成数据及实测数据的结果均证明所提方法的合理性, 有望将此方法推广到其他道路交通中具有固定结构交通工具的速度估计中。 相似文献
133.
为研究加工工艺对鸡酥松加工过程脂肪氧化的影响,考察蒸煮时间、蒸煮温度、炒松时间对2-硫代巴比妥酸值的影响,分析炒松工艺对鸡酥松脂肪氧化以及综合评分的影响,结果表明,炒松时间显著影响脂肪氧化,加工工艺中对脂肪氧化影响程度由大到小依次为炒松时间、蒸煮温度和初煮时间,而影响产品综合评估得分的因素由强至弱依次为炒松时间、初煮时间和蒸煮温度;优化后较适的加工工艺条件为初煮50min、复煮10min、蒸煮温度90℃、炒松时间20min、2-硫代巴比妥酸作用底物值为2.26mg/kg。产品综合评分与2-硫代巴比妥酸作用底物值的趋势并不完全吻合,鸡酥松加工过程中的工艺影响脂肪氧化程度和产品品质。 相似文献
134.
Yunshen Zhou Kedong Wang Fengzhou Zhao Bing Wang Jianguo Hou Shu Wang Yuliang Li 《科学通报(英文版)》2005,50(5):407-412
Self-assembled monolayers of novel C60 derivative, N-3-γ-pyridyl Aza[60]fulleroid (C60Py), on Au(111) were studied by a scanning tunneling microscope under ultrahigh vacuum (UHV). C60Py molecules were assembled on Au (111) via pyridyl nitrogen-Au interaction. The sole assembly of C60Py molecules on Au (111) only exhibited randoml aggregation of C60Py even the films were annealed at 50 and 105°C. By co-assembling with benzyl mercaptan (BM), the C60PyBM films showed highly dense aggregation, but C60Py assemblies still had disordered structure. After the co-assembled C60Py-BM films were annealed at 50°C, BM molecules were partially desorbed, but the assembly of C60Py remained without obvious change. After the co-assembled C60Py-BM films were further annealed at 105°C, the C60Py monolayers with ordered structure were obtained, while the BM molecules were nearly thoroughly desorbed from the surface.
Here, the BM molecules play a key role as a surfactant in the formation of the ordered C60Py monolayer. 相似文献
135.
CHENChuan-bo LIQi-shen GONGWen-jie 《武汉大学学报:自然科学英文版》2005,10(3):520-524
A new concept of characteristic scanning radial (CSR) is proposed for the segmented image on the basis of two shape-speciiic points oi its shape-objects. Subsequently, two characteristic attribute sequences (CAS) of relative distance and relative direction are derived to represent the spatial orientation relationships among objects of the image. A novel image retrieval algorithm is presented using these two CASs. The proposed retrieval approach not only satisfies the transformational invariance, but also attains the quantitative comparison of matching. Experiments identify the effectiveness and efficiency of the algorithm adequately. 相似文献
136.
137.
余多慰 《南京师大学报(自然科学版)》1991,14(4):114-124
本工作运用薄层扫描仪的扫描与数据处理功能,对处于400条带与550条带阶段的人类G带染色体进行定量分析,提出用相对位置、相对积分面积、阳性带吸光强度以及相对带宽值来识别区带,并对上述人类染色体的二种G带带型予以定量描述,还探讨了本工作与染色体自动识别、图象分析的关系。 相似文献
138.
139.
讨论了用差示扫描量热法(DSC法)鉴别细菌技术的可行性,尝试了在25 ̄500℃范围内对四种细菌进行快速的DSC扫描,并据所得图谱对细菌进行鉴别,获得了较满意的结果,为鉴别细菌提供了一种快速的手段。 相似文献
140.
Prochownik EV 《Cellular and molecular life sciences : CMLS》2005,62(21):2438-2459
The discovery of oncogenes (c-onc’s) and tumor suppressors (TS’s) has led to the concept that cancer arises from defects in
each of these classes of genes or their products. More recently, it has been appreciated that c-onc and TS proteins often
affect one another’s functions. Within this context, I review the two classical TS’s, p53 and the retinoblastoma protein,
and the consequences of their inactivation. The various forms of genomic instability (GI) that underly the high mutation rates
of transformed cells are then discussed. Particular emphasis is placed upon the concept that GI is not only an integral part
of the transformed state but is a prerequisite. Increased oxidative DNA damage, and/or an inabiliy to repair it, can lead
to GI. The review then discusses recent observations showing that loss of the TS protein peroxiredoxin 1 (prdx1) and increased
expression of the c-onc protein c-Myc, each leads to increased oxidative DNA damage. The critical nature of the c-onc-TS interaction
is underscored by that occurring between prdx1 and c-Myc, with the former protein regulating the production of DNA-damaging
reactive oxygen species by the latter. The intimate association between these proteins and others serves as a paradigm for
the exquisite balancing act that c-onc’s and TS’s must maintain in order to properly control normal DNA replication and cellular
proliferation while simultaneously minimizing the acquisition of potentially neoplastic mutations.
Received 10 May 2005; received after revision 3 July 2005; accepted 19 July 2005 相似文献