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电流信号突跃辅助下的时间比法提高毛细管电泳的再现性 被引量:3
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作者 张红医 李前锋 +2 位作者 陈兴国 王锐 胡之德 《分析化学》 SCIE EI CAS CSCD 北大核心 2001年第7期775-778,共4页
提出了一种提高毛细管电泳再现性的新方法———电流信号突跃辅助下的时间比法 (RM AS CC)。将电泳过程中一般都要记录的吸收信号 (光度检测器 ) ,与常常被忽略了的电流信号 ,同步传输给数据采集计算机。如果样品和背景电解质的电阻率不... 提出了一种提高毛细管电泳再现性的新方法———电流信号突跃辅助下的时间比法 (RM AS CC)。将电泳过程中一般都要记录的吸收信号 (光度检测器 ) ,与常常被忽略了的电流信号 ,同步传输给数据采集计算机。如果样品和背景电解质的电阻率不同 ,就会在电流图上出现一电流信号突跃。将各待测物的迁移时间除以这个电流突跃所对应的时间 ,就可求出相应的RM ASCC值。 展开更多
关键词 毛细管电泳 迁移时间比 再现性 电流信号突跃 时间比法 电毛细管分析
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几类复合反应的动力学数据处理方法(英文)
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作者 程四清 张元勤 曾宪诚 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第2期287-291,共5页
导出了几类反应通用的微分动力学方程,据此运用两种动力学数据处理方法——线性拟合法和时间比法——计算几类复合反应的速率常数.计算结果与文献值吻合较好。
关键词 数据处理方 线性拟合 时间比法 复合反应 动力学
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确定化学反应级数和速率常数方法的研究及应用 被引量:8
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作者 卢新生 苟如虎 +2 位作者 张海玲 刘伯渠 王亚玲 《牡丹江师范学院学报(自然科学版)》 2010年第1期29-31,共3页
兼有微分法和积分法优点的浓度——时间比法可以确定假设的条件和化学计量学是否正确,并据此提出比较复杂的速度表达式.
关键词 反应级数 微分 积分 时间-浓度比法
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Estimation of quality factors by energy ratio method 被引量:1
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作者 王宗俊 曹思远 +5 位作者 张浩然 曲英铭 袁殿 杨金浩 张德龙 邵冠铭 《Applied Geophysics》 SCIE CSCD 2015年第1期86-92,122,123,共9页
The quality factor Q, which reflects the energy attenuation of seismic waves in subsurface media, is a diagnostic tool for hydrocarbon detection and reservoir characterization. In this paper, we propose a new Q extrac... The quality factor Q, which reflects the energy attenuation of seismic waves in subsurface media, is a diagnostic tool for hydrocarbon detection and reservoir characterization. In this paper, we propose a new Q extraction method based on the energy ratio before and after the wavelet attenuation, named the energy-ratio method(ERM). The proposed method uses multipoint signal data in the time domain to estimate the wavelet energy without invoking the source wavelet spectrum, which is necessary in conventional Q extraction methods, and is applicable to any source wavelet spectrum; however, it requires high-precision seismic data. Forward zero-offset VSP modeling suggests that the ERM can be used for reliable Q inversion after nonintrinsic attenuation(geometric dispersion, refl ection, and transmission loss) compensation. The application to real zero-offset VSP data shows that the Q values extracted by the ERM and spectral ratio methods are identical, which proves the reliability of the new method. 展开更多
关键词 Quality factor Q energy ratio time domain seismic wavelet spectral ratio method
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Method of oxygen-enriched two-stage underground coal gasification 被引量:11
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作者 Liu Hongtao Chen Feng +2 位作者 Pan Xia Yao Kai Liu Shuqin 《Mining Science and Technology》 EI CAS 2011年第2期191-196,共6页
Two-stage underground coal gasification was studied to improve the caloric value of the syngas and to extend gas production times.A model test using the oxygen-enriched two-stage coal gasification method was carried o... Two-stage underground coal gasification was studied to improve the caloric value of the syngas and to extend gas production times.A model test using the oxygen-enriched two-stage coal gasification method was carried out.The composition of the gas produced,the time ratio of the two stages,and the role of the temperature field were analysed.The results show that oxygen-enriched two-stage gasification shortens the time of the first stage and prolongs the time of the second stage.Feed oxygen concentrations of 30%, 35%,40%,45%.60%,or 80%gave time ratios(first stage to second stage) of 1:0.12,1:0.21.1:0.51,1:0.64, 1:0.90.and 1:4.0 respectively.Cooling rates of the temperature field after steam injection decreased with time from about 19.1-27.4℃/min to 2.3-6.8℃/min.But this rate increased with increasing oxygen concentrations in the first stage.The caloric value of the syngas improves with increased oxygen concentration in the first stage.Injection of 80%oxygen-enriched air gave gas with the highest caloric value and also gave the longest production time.The caloric value of the gas obtained from the oxygenenriched two-stage gasification method lies in the range from 5.31 MJ/Nm^3 to 10.54 MJ/Nm^3. 展开更多
关键词 Underground coal gasification Enriched oxygen Two-stage gasification Temperature field
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Asymptotic Lifshitz-Like Solution in Lovelock Gravity (n=3)
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作者 于添翼 岳瑞宏 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第8期281-288,共8页
With R^2 and R^3 corrections to asymptotical Lifshitz space-time, we obtain pure Lovelock gravity solution and solution with non-trivial matter in 7-dimensional space-time. Then we obtain the general solution for any ... With R^2 and R^3 corrections to asymptotical Lifshitz space-time, we obtain pure Lovelock gravity solution and solution with non-trivial matter in 7-dimensional space-time. Then we obtain the general solution for any arbitrary dimensional space. In this paper, we also study black brane solutions in 7-dimensionai Lifshitz space-time via the method of perturbation. And we popularize the black brane solution to arbitrary higher dimensions and discuss the ratio of shear viscosity to entropy density ratio η/s. Then we analyze the result of η/s to find that the correction of n-th (n ≥ 3) order Lovelock term has trivial influence to η/s. 展开更多
关键词 Lovelock gravity black hole black brane Horava-Lifshitz theory Lifshitz gravity shear viscosity
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Levenberg-Marquardt based artificial physics method for mobile robot oscillation alleviation 被引量:6
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作者 ZHANG XiangYin DUAN HaiBin LUO QiNan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第9期1771-1777,共7页
This paper proposed a modified artificial physics(AP)method to solve the autonomous navigation problem for mobile robots in complex environments.The basic AP method tends to cause oscillations in the presence of obsta... This paper proposed a modified artificial physics(AP)method to solve the autonomous navigation problem for mobile robots in complex environments.The basic AP method tends to cause oscillations in the presence of obstacles and in narrow passages,which can result in time consumption.To alleviate oscillation,we modified the AP method using the Levenbery-Marquardt(LM)algorithm.In the modified AP method,we altered the original directions of AP forces to the Newton direction,and adjust the parameter by the LM algorithm.A series of comparative experimental results show that the modified AP method can achieve smoother trajectories with less time consumption.This demonstrates the feasibility and effectiveness of our proposed approach. 展开更多
关键词 artificial physics(physicomimetics) Levenbery-Marquardt(LM) algorithm autonomous navigation obstacle avoidance
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