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A trial study of vibration-induced effects on the spontaneous potential
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作者 孙卫斌 裘慰庭 何展翔 《Applied Geophysics》 SCIE CSCD 2008年第2期144-148,共5页
Vibrator excitation generates not only reflections and refractions of wave fields on the subsurface interfaces but also electromagnetic waves with different frequencies. In this paper, we address the vibration-induced... Vibrator excitation generates not only reflections and refractions of wave fields on the subsurface interfaces but also electromagnetic waves with different frequencies. In this paper, we address the vibration-induced effects on the spontaneous potential field. The effects of controllable vibration on the spontaneous potential field were studied under real field geologic conditions. Experimental data confirmed that the vibration-induced effects on the spontaneous potential field do exist under field conditions. Monitoring records over a long time interval showed that there exist three information zones in the vibration-induced effects on the spontaneous potential field. These are the signal-varying zone, the extremestable zone, and the relaxation-recovery zone. Combined with different well-site data, it was concluded that the time-varying features of the anomalies in the information zones was closely related to the properties of the subsurface liquid (oil and water). 展开更多
关键词 seismic-electric effects vibration-induced time-varying features the property of liquid
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Effect of heat transfer space non-uniformity of combustion chamber components on in-cylinder soot emission formation in diesel engine
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作者 吕继组 白敏丽 +1 位作者 李晓杰 周龙 《Journal of Central South University》 SCIE EI CAS 2011年第1期271-278,共8页
Combustion chamber components (cylinder head, cylinder liner, piston assembly and oil film) are treated as a coupled body. Based on the three-dimensional numerical simulation of heat transfer of the coupled body, a ... Combustion chamber components (cylinder head, cylinder liner, piston assembly and oil film) are treated as a coupled body. Based on the three-dimensional numerical simulation of heat transfer of the coupled body, a coupled three-dimensional calculation model for the in-cylinder working process and the combustion chamber components was built with domain decomposition and boundary coupling method, in which the coupled three-dimensional simulation of in-cylindcr working process and the combustion chamber components was adopted. The simulation was applied in the influence investigation of the space non-uniformity in heat transfer among combustion chamber components on the generation of in-cylinder emissions. The results show that the space non-uniformity in heat transfer among the combustion chamber components has great influence on the generation of in-cylinder NOx emissions. The heat transfer space non-uniformity of combustion chamber components has little effect on soot formation, and far less effect on soot formation than on NOx. Under two situations of different wall temperature distributions, the soot in cylinder is different by 1.3% when exhaust valves are open. 展开更多
关键词 heat transfer space non-uniformity soot emission IN-CYLINDER DIESEL
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盐酸纳美芬缺血后处理通过AMPK/Nrf2/HO-1途径减轻大鼠肺缺血-再灌注损伤的时效性研究 被引量:1
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作者 徐标 李鸣 +1 位作者 王继武 李文华 《中华急诊医学杂志》 CAS CSCD 北大核心 2023年第12期1686-1692,共7页
目的研究纳美芬缺血后处理通过AMPK/Nrf2/HO-1途径减轻肺缺血-再灌注损伤的作用机制及给药时效性。方法将90只大鼠随机(随机数字表法)均分为模型组、纳美芬A、B、C、D、E、F、G组、假手术组共9组,每组10只。模型组大鼠采用阻断左肺门法... 目的研究纳美芬缺血后处理通过AMPK/Nrf2/HO-1途径减轻肺缺血-再灌注损伤的作用机制及给药时效性。方法将90只大鼠随机(随机数字表法)均分为模型组、纳美芬A、B、C、D、E、F、G组、假手术组共9组,每组10只。模型组大鼠采用阻断左肺门法建立肺缺血-再灌注模型,未予药物治疗。造模后纳美芬A、B、C、D组大鼠分别于肺循环再灌注前5 min、再灌注后10 min、30 min、60 min时予尾静脉注射纳美芬(小剂量组,15μg/kg)。纳美芬E组大鼠于肺循环再灌注后60 min时予尾静脉注射纳美芬(30μg/kg)。纳美芬F、G组大鼠分别于造模前2 h腹腔注射化合物C(20 mg/kg)、ML385(30 mg/kg),同时在肺循环再灌注前5 min时尾静脉注射纳美芬(15μg/kg)。假手术组大鼠不行缺血-再灌注处理,未予药物治疗。各组大鼠于再灌注3 h末处死后均留取左肺上叶组织,通过病理切片观察评估肺组织损伤评分,检测肺组织湿/干重比值,以生化法检测肺组织TNF-α和丙二醛(malondialdehyde,MDA)含量、超氧化物歧化酶(superoxide dismutase,SOD)活性,RT-PCR法测定肺组织核因子E2相关因子2((nuclear factor erythroid-2 related factor 2,Nrf2))mRNA、血红素加氧酶1(heme oxygenase 1,HO-1)mRNA表达水平以及Western blot法检测大鼠肺组织AMP依赖的蛋白激酶(Adenosine 5'-monophosphate(AMP)-activated protein kinase,AMPK)、p-AMPK(磷酸化AMPK)、Nrf2、HO-1表达水平。结果与模型组比较,纳美芬D组湿/干重比值、肺组织损伤评分、p-AMPK、p-AMPK/AMPK、Nrf2mRNA、HO-1mRNA、Nrf2、HO-1表达水平、TNF-α和MDA含量、SOD活性差异均无统计学意义(均P>0.05)。与模型组、纳美芬D组比较,纳美芬E组湿/干重比值、肺组织损伤评分、TNF-α和MDA含量下降,差异有统计学意义(均P<0.01),p-AMPK、p-AMPK/AMPK、Nrf2mRNA、HO-1mRNA、Nrf2、HO-1表达水平、SOD活性增高,差异有统计学意义(均P<0.01)。与模型组比较,纳美芬F组湿/干重比值、肺组织损伤评分、TNF-α和MDA含量下降,差异有统计学意义(均P<0.01),Nrf2mRNA、HO-1mRNA、Nrf2、HO-1表达水平和SOD活性增高,差异有统计学意义(均P<0.01),p-AMPK、p-AMPK/AMPK表达水平差异均无统计学意义(均P>0.05)。与纳美芬A组比较,纳美芬F组湿/干重比值、肺组织损伤评分、TNF-α和MDA含量增高,差异有统计学意义(均P<0.01),p-AMPK、p-AMPK/AMPK、Nrf2mRNA、HO-1mRNA、Nrf2、HO-1表达水平和SOD活性降低,差异有统计学意义(均P<0.01)。与模型组比较,纳美芬G组湿/干重比值、肺组织损伤评分、TNF-α含量下降,p-AMPK、p-AMPK/AMPK表达水平增高,差异有统计学意义(均P<0.01),Nrf2mRNA、HO-1mRNA、Nrf2、HO-1表达水平、MDA含量、SOD活性差异均无统计学意义(均P>0.05)。与纳美芬A组比较,纳美芬G组湿/干重比值、肺组织损伤评分、TNF-α和MDA含量增高,差异有统计学意义(均P<0.01),p-AMPK、p-AMPK/AMPK表达水平差异均无统计学意义(均P>0.05),Nrf2mRNA、HO-1mRNA、Nrf2、HO-1表达水平和SOD活性降低,差异有统计学意义(均P<0.01)。小剂量(15μg/kg)纳美芬缺血后处理各组在湿/干重比值、肺组织损伤评分、TNF-α和MDA含量方面呈现纳美芬D>纳美芬C>纳美芬B>纳美芬A的特点,在p-AMPK、p-AMPK/AMPK、Nrf2mRNA、HO-1mRNA、Nrf2、HO-1表达水平、SOD活性方面呈现纳美芬A>纳美芬B>纳美芬C>纳美芬D的特点,上述结果差异均存在统计学意义(均P<0.01)。结论盐酸纳美芬缺血后处理可通过AMPK/Nrf2/HO-1通路抑制氧化应激,减轻肺缺血-再灌注损伤,此作用具有时效性特点,超过某一特定有效时间窗口时,纳美芬治疗对肺缺血-再灌注损伤可能无效,增大药物剂量可能改变或延长有效时间窗。 展开更多
关键词 盐酸纳美芬 缺血后处理 肺缺血-再灌注损伤 AMPK/Nrf2/HO-1通路 时间-效应性
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Properties of Linear Entropy in k-Photon Jaynes-Cummings Model with Stark Shift and Kerr-Like Medium
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作者 廖庆洪 Muhammad Ashfaq Ahmad +1 位作者 王月媛 刘树田 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期931-936,共6页
The time evolution of the linear entropy of an taking into consideration Stark shift and Kerr-like medium. atom in k-photon daynes-Cummings model is investigated The effect of both the Stark shift and Kerr-like medium... The time evolution of the linear entropy of an taking into consideration Stark shift and Kerr-like medium. atom in k-photon daynes-Cummings model is investigated The effect of both the Stark shift and Kerr-like medium on the linear entropy is analyzed using a numerical technique for the field initially in coherent state and in even coherent state. The results show that the presence of the Kerr-like medium and Stark shift has an important effect on the properties of the entropy and entanglement. It is also shown that the setting of the initial state plays a significant role in the evolution of the linear entropy and entanglement. 展开更多
关键词 k-photon Jaynes Cummings model linear entropy stark shift Kerr-like medium
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Alkaline extraction characteristics of steelmaking slag batch in NH_4Cl solution under environmental pressure 被引量:2
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作者 张慧宁 徐安军 +1 位作者 贺东风 崔健 《Journal of Central South University》 SCIE EI CAS 2013年第6期1482-1489,共8页
In order to obtain better carbonation effect, extraction behavior of slag batch is necessary to study. Relevant parameters like selective extraction yield were originally discussed. The relationship between selective ... In order to obtain better carbonation effect, extraction behavior of slag batch is necessary to study. Relevant parameters like selective extraction yield were originally discussed. The relationship between selective extraction yield and conversion ratio was systemically focused on. The results show that alkaline earth metal conversion ratio is changed with leaching time and NH4CI concentration by first order exponential, and the maximum conversion for calcium keeps about 68% at 120 min in 0.4 mol/L NH4C1 solution, while leaching temperature and particle size have a linear effect on conversion ratio. Selective extraction yield of calcium is more than 93%, and the value of Mg is less than 5%. Apparent layer bands of silicon and calcium appear in the surface area through morphology detection of slag after leaching, and the case for 38-75 μm slag batch is more obvious than 75 150 μm slag and slag with larger particle size when leaching in 0.4 mol/L NH4Cl solution for 90 rain at 60 ℃. 展开更多
关键词 steel slag alkaline leaching NH4Cl solution selective extraction yield conversion ratio
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Control of Sudden Death of Entanglement by Transient Effects 被引量:3
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作者 Hünkar Kayhan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第9期487-489,共3页
We investigate the properties of entanglement between an isolated atom and a Jaynes-Cummings atom in the presence of transient effects. These effects are due to the modulation of the atom-field coupling whose explicit... We investigate the properties of entanglement between an isolated atom and a Jaynes-Cummings atom in the presence of transient effects. These effects are due to the modulation of the atom-field coupling whose explicit time-dependence is considered for the case of the linear sweep. We show that the sudden death of entanglement can be controlled by the transient effects. These effects can suppress the sudden death of entanglement in time. 展开更多
关键词 sudden death of entanglement transient effects Jaynes--Cummings model
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Evolution of the Ionospheric Plasma Turbulence over Seismic and Thunderstorm Areas
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作者 Jan Blccki Michel Parrot +3 位作者 Jan Slomiflski Malgorzata Kogciesza Roman Wronowski Sergey Savin 《Journal of Environmental Science and Engineering(A)》 2016年第6期277-285,共9页
The authors report the observation of Extremely Low Frequency (ELF) plasma turbulence registered by DEMETER satellite in the ionosphere over the seismic and thunderstorm areas. The detail analysis of the electric fi... The authors report the observation of Extremely Low Frequency (ELF) plasma turbulence registered by DEMETER satellite in the ionosphere over the seismic and thunderstorm areas. The detail analysis of the electric field fluctuations for the selected strong earthquakes and thunderstorm is presented. Special attention is given to study of the characteristics of the spectra of these variations and searches of the nonlinear effects. This analysis is possible in the time interval when the waveform has been transmitted. Some attempt of this discussion is given in the paper. 展开更多
关键词 EARTHQUAKES IONOSPHERE LIGHTNING plasma turbulence thunderstorms.
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The Crucial Role of Time in M&A Activities: An Inductive Exploration
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作者 Nicole Zadrazil Othmar Lehner Heimo Losbichler 《Journal of Modern Accounting and Auditing》 2017年第8期350-370,共21页
Mergers & acquisitions (M&As) are important strategic instruments, yet nearly half of all transactions fail, often resulting in disastrous write-offs and losses for corporations and financing institutions alike - ... Mergers & acquisitions (M&As) are important strategic instruments, yet nearly half of all transactions fail, often resulting in disastrous write-offs and losses for corporations and financing institutions alike - despite promising prospects upfront. Applied research has been trying to find a "panacea" to prevent or at least predict M&A failure, investigating motives, synergies and performance. Despite the growing unease with the stationary explanatory models in literature, research has only marginally focused on the concept of time, with inquiries into market timing and integration speed. Yet other timing concepts have been neglected in concepts so far despite early empirical evidence for their existence. The purpose of this paper is thus to identify and elaborate on the importance of further relevant theories of timing. For this, and true to the exploratory nature of the topic, the authors have chosen a qualitative comparative case study design based on existing case reports which are investigated for narrations highlighting timing concepts. This study reveals six factors which have a crucial impact on the M&A outcome: time of acquisition, M&A duration in its entirety, M&A sequence, synergy chronology, frequency of acquisitions and time to step back. It contributes to theory and practice in outlining the careful attention that needs to be paid in planning in these factors to enhance the chances of a successful M&A transaction. 展开更多
关键词 M&A SUCCESS timing concepts process SYNERGY
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