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EXPERI MENTAL INVESTIGATION INTO HOT WATER SLOT JETS WITH NEGATIVELY BUOYANCYIN CROSS FLOW

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Journal of Hydrodynamics 2005年第4期17卷 412-417页

作者： YANG zhong-hua huai Wen-xin DAI Hui-chao State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

An experiment was conducted to examine the near-field behavior of negatively buoyant planar jets in flowing environment. Hot water jet was projected downwards at dif fercnt angles from a slot into a uniform cross flow. Micro Acoustic Doppler Velocimeter （Micro ADV） system is used to measure the velocity and turbulent fluxes of Reynolds stresses. The whole field temperatures were measured with fast response thermocouples. Pure jets experiments were made also to study the effect of buoyancy in negatively buoyant jets. It is found that the influenced area of hot jets is larger than which of pure jets when the jet angle is 90° and the influenced area of hot jets is smaller than which of pure jets when the jet angle is 45°. The difference is not obvious at 60° angle jets. This means that the rising of temperature has effect not only on negatively buoyancy, but also on the intensity of turbulence. The contrast of these two influences dominates the trend of jet flow.

关键词： negatively buoyant planar jets Micro Acoustic Doppler Velocimeter (Micro ADV) Reynolds stresses

Effects of Time Delay on Multistability of Genetic Toggle Switch

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： De-qing Zhu Hui-jun Jiang zhong-huai Hou Department of Chemical Physics & Hefei National Laboratory for Physical Sciences at the Microscales iChEM University of Science and Technology of China Hefei 230026 China

The effect of time delay on a genetic toggle switch, whose undelayed dynamics shows low protein expression states (L-states), high expression states (H-states) and coexistence of them different transcription-factor binding rates α, is investigated by using the delayed stochastic simulation method. Interestingly, we find that the delay induces a transition from the coexistence state to L-state or H-state by suppressing the other state. Moreover, the phase diagram on the α-τ plane is obtained by extensive simulations. It is observed that, the coexistence state is remarkably narrowed by increasing delay time, and completely disappears above a triple-point-like point where direct transitions between H-state and L-state are possible.

关键词： Genetic toggle switch Delay Multistability

System Size Resonance Associated with Canard Phenomenon in a Biological Cell System

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Chinese Journal of Chemical Physics 2008年第6期21卷 521-525页

作者： Juan Ma Hong-ying Li zhong-huai Hou Hou-wen Xin Department of Chemical Physics University of Science and Technology of China Hefei 230026 China Hefei National Lab of Physical Science at Microscale University of Science and TechnoloEy of China Hefei 230026 China Department of Chemistry Hefei Teachers College Hefei 230000 China

The influence of internal noise on the calcium oscillations is studied. It is found that stochastic calcium oscillations occur when the internal noise is considered, while the corresponding deterministic dynamics only yields a steady state. Also,. the performance of such oscillations shows two maxima with the variation of the system size, indicating the occurrence of system size resonance. This behavior is found to be intimately connected with the canard phenomenon. Interestingly, it is also found that one of the optimal system sizes matches well with the real cell size, and such a match is robust to the variation of the control parameters.

关键词： Internal noise Calcium oscillations System size resonance Canard phenomenon

Vertical variation of trace elements and its relation to the water-bearing capacity of Ordovician strata,in Datun coal field

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Mining Science and Technology 2009年第2期19卷 166-169页

作者： LIU huai-zhong HAN Bao-ping School of Resources and Geoscience China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Environmental Science and Spatial lnformatics China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

We tested for fourteen trace elements in samples collected from the Ordovician strata in Datun coal field. The vertical concentration variation of these trace dements is reported. The relationship of the variation to the water-bearing capacity of the Ordovician strata is discussed. The minimum concentration of eleven （of 14 total） trace elements appears in the lower Majiagou formation. The maximum concentrations mainly appear in the Badou and Jiawang formations： eight maxima are located in Badou and four more are in Jiawang. The study of karst development and the water-bearing capacity of Ordovician strata shows that karst is well developed in the Majiagou formation and there is a consequent high water-bearing capacity in this formation： Badou and Jiawang formations are contrary to this situation. The results illustrate that the minimum concentrations of most trace elements within certain Ordovician formations can be taken as strong evidence for the existence of a well developed karst and a high water-bearing capacity.

关键词： Ordovician trace element water-bearing capacity Damn coal field

Generalized Drazin spectrum of operator matrices

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Applied Mathematics(A Journal of Chinese Universities) 2014年第2期29卷 162-170页

作者： ZHANG Shi-fang zhong huai-jie LIN Li-qiong School of Mathematics and Computer Science Fujian Normal University College of Mathematics and Computer Science Fuzhou University

Let A ∈ B（X） and B ∈ B（Y）, Me be an operator on Banach space X ＋ Y given by Mc =（A C 0 B）A generalized Drazin spectrum defined by σgD（T） = {λ∈C ： T-λI is not generalized Drazin invertible} is considere... 详细信息

关键词： operator matrices generalized Drazin spectrum filling-in-hole problem.

Explosive Synchronization and Emergence of Assortativity on Adaptive Networks

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Chinese Physics Letters 2011年第5期28卷 198-201页

作者： JIANG Hui-Jun WU Hao HOU zhong-huai Department of Chemical Physics and Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026

We report an explosive transition from incoherence to synchronization of coupled phase oscillators on adaptive networks,following an Achlioptas process based on dynamic clustering *** each adaptive step of the network topology,a portion of the links is randomly removed and the same amount of new links is generated following the so-called product rules(PRs)applied to the dynamic ***,two types of PRs are considered,namely,the min-PR and *** demonstrate that the synchronization transition becomes explosive in both ***,we find that the min-PR rule can lead to disassortativity of the network topology,while the max-PR rule leads to assortativity.

关键词： synchronization Synchronization network

Experimental investigation on the cuttings formation process and its relationship with cutting force in single PDC cutter tests

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Petroleum Science 2023年第3期20卷 1779-1787页

作者： Xian-Wei Dai zhong-Wei Huang Tao Huang Peng-Ju Chen huai-zhong Shi Shuang Yan State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanPR China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum-BejingBeijing102249PR China PetroChina Southwest Oil and Gasfield Company Northeast Sichuan Gas District PR China

The single polycrystalline diamond compact(PDC)cutter test is widely used to investigate the mecha-nism of *** generated cuttings and cutting force are important indexes reflecting the rock failure ***,they were treated as two separate parameters in previous *** this study,through a series of rock block cutting tests,the relationship between them was investigated to obtain an in-depth understanding of the formation of *** addition,to validate the standpoints obtained in the aforementioned experiments,rock sheet cutting tests were conducted and the rock failure process was monitored by a high-speed camera frame by *** cutting force was recorded with the same sampling rate as the *** this design,every sampled point of cutting force can match a picture captured by the camera,which reflects the interaction between the rock and the *** results indicate that the increase in cutting depth results in a transition of rock failure *** shallow cutting depth,ductile failure dominates and all the cuttings are produced by the compression of the *** corresponding cutting force fluctuates ***,beyond the critical depth,brittle failure occurs and chunk-like cuttings appear,which leads to a sharp decrease in cutting *** that,the generation of new surface results in a significant decrease in actual cutting depth,a parameter proposed to reflect the interaction between the rock and the ***,ductile failure dominates again and a slight fluctuation of cutting force can be *** the cutter moves to the rock,the actual cutting depth gradually increases,which results in the subsequent generation of chunk-like *** is accompanied by an obvious cutting force *** is,ductile failure and brittle failure,one following another,present at large cutting *** transition of rock failure mode can be correlated with the variation of cutting *** on the results of

关键词： Rock breaking Cutting force PDC cutter Cuttings

Catalytic Oscillatory Oxidation of CO on Pt(110): on-off Control to Chaos

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Chinese Physics Letters 1998年第9期15卷 695-696页

作者： YANG Ling-fa HOU zhong-huai XIN Hou-wen Department of Chemical Physics University of Science and Technology of ChinaHefei 230026

An improved mean-field model,which specially takes into account pair correlation,was proposed to describe catalytic oscillatory oxidation of CO on Pt(110).By applying on-off control strategies under different frequency,the chemical oscillator shows an abundance of periodic doubling processes,even chaos response,and the route to the chaos and out of the chaos were both identified as period-doubling through analysis of its Lyapunov exponent *** response results reveal that structure delay effect plays an important role to the complexity of this system.

关键词： spectrum. chaos doubling

Experimental studies on rock failure mechanisms under impact load by single polycrystalline diamond compact cutter

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Petroleum Science 2023年第5期20卷 3100-3109页

作者： Zhao-Sheng Ji Jin-Bao Jiang huai-zhong Shi Bang-Min Li Drilling Engineering Technology Research Institute Sinopec Zhongyuan Petroleum Engineering CompanyPuyangHenan457001China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China

Percussive drilling shows excellent potential for promoting the rate of penetration(ROP)in drilling hard *** diamond compact(PDC)bits account for most of the footage drilled in the oil and gas *** reveal the rock failure mechanisms under the impact load by PDC bits,a series of drop tests with a single PDC cutter were conducted to four kinds of rocks at different back rake angles,drop heights,drop mass,and drop *** the morphology characteristics of the craters were obtained and quantified by using a three-dimensional *** fracture micrographs can be observed by using scanning electron microscope(SEM).The distribution and propagation process of subsurface cracks were captured in rock-like silica glass by a high-speed photography *** results can indicate that percussive drilling has a higher efficiency and ROP when the rock fractures in brittle *** failure mode of rock is related with the type of rock,the impact speed,and the back rake angle of the *** the penetration depth and fragmentation volume get the maximum values at a back rake angle of about 45°.Increasing the weight and speed of falling hammer is beneficial to improving the rock breaking effects and *** subsurface cracks under the impact load by a single PDC cutter is shaped like a clamshell,and its size is much larger than the crater *** findings can help to shed light on the rock failure mechanisms under the impact of load by a single PDC cutter and provide a theoretical explanation for better field application of percussive drilling.

关键词： Percussive drilling PDC cutter Drop test Failure mechanism Subsurface cracks