搜索结果: 1-11 共查到“知识库 理学 TDR”相关记录11条 . 查询时间(0.062 秒)
Preferential transport of water and 131Iodide in a clay loam assessed with TDR-techniques and boundary-layer flow theory
clay loam soil moisture variations boundary-layer flow
2009/6/8
Rapid soil moisture variations were measured with TDR equipment at five depths ranging from 0.1 to 0.9 m during five consecutive infiltration experiments under ponding. Each time, 27 mm of water were ...
Extension of the measurement range of electrical conductivity by time-domain reflectometry (TDR)
electrical conductivity time-domain reflectometry
2009/6/8
The electrical conductivity (EC) of a medium invaded by TDR sensors can be estimated from the impedance of a TDR reflectogram. Four categories of sensor were tested in salt solutions and the impedance...
A fast TDR-inversion technique for the reconstruction of spatial soil moisture content
soil moisture TDR-inversion technique
2009/5/18
Spatial moisture distribution in natural soil or other material is a valuably information for many applications. Standard measurement techniques give only mean or punctual results. Therefore a new inv...
Efficient reconstruction of dispersive dielectric profiles using time domain reflectometry (TDR)
time domain reflectometry dispersive dielectric profiles
2009/5/13
We present a numerical model for time domain reflectometry (TDR) signal propagation in dispersive dielectric materials. The numerical probe model is terminated with a parallel circuit, consisting of a...
Practical considerations on the use of down-sized time-domain reflectometry (TDR) probes
TDR probepulse travel time dielectric constant electrical conductivity
2009/3/17
Nine time-domain reflectometry (TDR) probes, 2 to 10 cm long, were evaluated by comparing their measurement accuracy of TDR-pulse travel time in a sand and sandy loam soil, and electrical conductivity...
在甜椒（Capsicum frutescens L.）花药培养中3H-TdR掺入的放射自显影。
TDR 技术监测地下水位
时域反射技术 地下水位 监测
2008/6/6
本文介绍了一种监测地下水位的新方法，该方法利用脉冲波遇到电缆中空气与水的接触面时会产生
反射波的原理，用监测系统对反射波的到达时间进行测量、计算，就能确定地下水位。文章给出了一个室
内模拟试验的实例，证实了TDR 监测地下水位的技术方法是有效的、可行的。
摘要本文报告了用液体闪烁计数方法对5例华东地区的着色性干皮病病人外周血淋巴细胞进行DNA切除复功能的研究。结果发现，这5例病人淋巴细胞中的DNA切除修复功能都有以下。作者提出了紫外线诱发淋巴细胞非合成期3H-TdR掺入指数的大小代表DNA切除修复功能的高低，并想据实验结果与临床资料分析，认为DNA修复的程度与着色性干皮病的病情进展可能存在着直接关系。这与Takebe（1978）的结论是一致的。
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摘要 恶性肿瘤细胞或粘着于基膜以及在一定的基质上增殖对于肿瘤的浸润转移至关重要。层粘连蛋白(1aminin,LN)是基膜所特有的非胶原糖蛋白。我们研究了LN在肿瘤细胞粘着、铺展及增殖中的作用。通过测定粘着细胞所释放的LDH活性定量分析细胞粘着率。LN可显著增加体外培养的小鼠S180-V肉瘤及B16-MBK黑色素瘤细胞在玻璃及Ⅳ型胶原基质上粘着及铺展。纤维粘连蛋白(fibronectin,FN)亦有...
摘要 本文通过斑点印渍杂交技术和放射免疫分析方法,首次证实,~3H-TdR放射线转化C3H/10T1/2细胞株可高表达TGFα mRNA,并可向细胞外分泌具有免疫活性的TGFα分子,而非转化对应细胞中虽有TG FαmRNA的弱表达,但其无血清培养上清中未测到TGFα的分泌。表明TGFα参与了放射线对细胞的转化以及维持转化细胞增殖的过程。提示TGFα在三大致癌因素转化细胞中的存在可能具有普遍意义。同...
~3H-TdR转化细胞蛋白质酪氨酸残基的特异磷酸化
2007/12/19
摘要 1980年,Hunter首次发现Rous肉瘤病毒转化的细胞,其蛋白质分子上的酪氨酸残基磷酸化水平明显升高。现已知道,其它的肿瘤病毒诱导的转化细胞以及某些恶性肿瘤细胞的酪氨酸残基磷酸化作用亦有不同程度的增强。但迄今物理的致癌因素如放射性同位素引起的细胞转化是否伴随着酪氨酸特异的磷酸化的增强,尚未见报道。因此,本实验对C_3H10