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The rock breaking and ROP increase mechanisms for single-tooth torsional impact cutting using DEM

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Petroleum Science 2019年第5期16卷 1134-1147页

作者： Xiao-hua zhu Yun-Xu Luo Wei-ji Liu School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China Postdoctoral Research Station for Oil and Gas Engineering Southwest Petroleum UniversityChengdu 610500China

Torsional impact drilling is a new technology which has the advantages of high rock-breaking efficiency and a high rate of penetration(ROP).So far,there is no in-depth understanding of the rock-breaking mechanism for the ROP increase from torsional impact ***,it has practical engineering significance to study the rock-breaking mechanism of torsional *** this paper,discrete element method(DEM)software(PFC2 D)is used to compare granite breaking under the steady and torsional impacting ***,the energy consumption to break rock,microscopic crushing process and chip characteristics as well as the relationship among these three factors for granite under different impacting frequencies and amplitudes are *** is found that the average cutting force is smaller in the case of torsional impact cutting(TIC)than that in the case of steady *** mechanical specific energy(MSE)and the ratio of brittle energy consumption to total energy are negatively correlated;rock-breaking efficiency is related to the mode of action between the cutting tooth and ***,the ROP increase mechanism of torsional impact drilling technology is that the ratio of brittle energy consumption under the TIC condition is larger than that under a steady load;the degree of repeated fragmentation of rock chips under the TIC condition is lower than that under the steady load,and the TIC load promotes the formation of a transverse cracking network near the free surface and inhibits the formation of a deep longitudinal cracking network.

关键词： Torsional impact rock breaking Mechanical specific energy Fractal dimension Microcrack DEM

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Mira Symbiotic Stars

Chinese Journal of Astronomy and Astrophysics 2007年第1期7卷 101-110页

作者： Guo-Liang Lu Chun-hua zhu Zhan-Wen Han National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Department of Physics Xinjiang University Urumqi 830046

We have carried out a detailed study of Mira symbiotic stars by means of a population synthesis code. We estimate the number of Mira symbiotic stars in the Galaxy as 1700 - 3100 and the Galactic occurrence rate of Mira symbiotic novae as from -0.9 to 6.0 yr^-1, depending on the model assumptions. The distributions of the orbital periods, the masses of the components, mass-loss rates of cool components, mass-accretion rates of hot components and Mira pulsation periods in Mira symbiotic stars are simulated. By a comparison of the number ratio of Mira symbiotic stars to all symbiotic stars, we find the model with the stellar wind model of Winters et al. to be reasonable.

关键词： binaries symbiotic-Galaxy stellar content-stars Mira variables

A quantum image dual-scrambling encryption scheme based on random permutation

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Science China(Information Sciences) 2019年第12期62卷 286-295页

作者： Hai-hua zhu Xiu-Bo CHEN Yi-Xian YANG Information Security Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and Telecommunications School of Computer and Information Technology Nanyang Normal University Sate Key Laboratory of Public Big Data Guizhou University

Dear editor,A popular image encryption scheme is the dualscrambling scheme that combines position transformation and bit-plane transformation. This scheme makes the image chaotic by changing the coordinate positions o... 详细信息

关键词： image A quantum image dual-scrambling encryption scheme based on random permutation

Population synthesis of high mass X-ray binaries

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Research in Astronomy and Astrophysics 2011年第3期11卷 327-334页

作者： Guo-Liang Lu Chun-hua zhu Zhao-Jun Wang School of Physics Xinjiang University .Urumqi 830046 China Xinjiang University-National Astronomical ObserVatories Joint＇Center for Astrophysics Urumqi830046 China National Astronomical Observatories / Urumqi Observatory Chinese Academy of Sciences Urumqi 830011 China

By simulating the evolution of spin periods of magnetized neutron stars which interact with their environment in binary systems,we investigate the Galactic population of high mass X-ray binaries（HMXBs） .The number of HMXBs in the Galaxy is between 190 and 240,and their birthrate is from 5.9×10-5 yr-1 to 6.3× 10-5 *** the Corbet diagram（the positions of the spin periods *** orbital periods of HMXBs） in our model with the associated observations,we find that the stellar wind structure and the process of matter transfer are very important for understanding HMXBs.

关键词： stars:evolution—X-rays:binaries—Galaxy:stellar content

Enhanced electrochemical oxidation of phenol by introducing ferric ions and UV radiation

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Journal of Environmental Sciences 2008年第11期20卷 1386-1391页

作者： MAO, Xuhui WEI, Lin HONG, Song zhu, hua LIN, An GAN, Fuxing School of Resource and Environmental Science Environmental Engineering Department Wuhan University Wuhan 430079 China

The mineralization of phenol in aerated electrochemical oxidation has been *** results show that a cathodic Fenton process can occur when the Ti-0.3Mo-0.8Ni alloy material is used as cathode in solution containing ferric or ferrous ions; moreover,the reinforcement of cathodic Fenton process on the total organic carbon (TOC) removal rate of phenol is quite *** the metallic ions investigated,the ferric ion is the best catalyst for the electrochemical mineralization of phenol at initial...

关键词： mineralization phenol electrochemical oxidation cathodic Fenton process UV radiation

Eco-environmental benefit assessment of China's South-North Water Transfer Scheme——the middle route project

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Journal of Environmental Sciences 2004年第2期16卷 308-315页

作者： DUANGuang-ming ZHAOJing-zhu LIUGuo-hua KEBing XIAOHan WUGang DENGHong-bing KeyLaboratoryofSystemEcology ResearchCentreforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China.

This paper assess the eco-environmental benefits that may come from the middle route project of China's South-North Water Transfer Scheme(SNWT) with principles and methods of eco-economics and planning reports of SNWT's middle route project. Some benefits were calculated in monetary units. To make sure that the results can be comparable with normal monetary indices, concrete assessment objects and the parameters are prudently selected according to the major characteristics of the project and its water import region. Primary assessment revealed that in different project construction stages, the benefit could be more than 13 07 billion RMB Yuan in 2010 and 19 79 billion RMB Yuan in 2030, respectively. The monetary value tends to increase with social-economic development. To realize these potential benefits, however, calls for more endeavors.

关键词： China's South-North Water Transfer Scheme(SNWT) the middle route project of South-North Water Transfer(MRPSNWT) assessment ecosystem services monetary indices

Population synthesis of ultra-compact X-ray binaries

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Research in Astronomy and Astrophysics 2012年第11期12卷 1526-1534页

作者： Chun-hua zhu Guo-Liang Lu Zhao-Jun Wang School of Physical Science and Technology Xinjiang University Urumqi 830046 China

Ultra-compact X-ray binaries （UCXBs） are very interesting and impor- tant objects. By taking the population synthesis approach to the evolution of binaries, we carry out a detailed study of UCXBs. We estimate that there are - 5000-10000 UCXBs in the Galaxy, and their birthrates are - 2.6-7.5×10-4 yr-1. Most UCXBs are transient X-ray sources, but their X-ray luminosities are much lower than those of persistent sources. Therefore, the majority of observed UCXBs should be persistent sources. About 40% - 70% of neutron stars （NSs） in UCXBs form via an accretion- induced collapse from an accreting ONe white dwarf （WD）, 1%-10% of NSs in UCXBs form via core-collapse supernovae and others form via the evolution-induced collapse of a naked helium star. About 50% - 80% of UCXBs have naked helium star donors, 5% - 10% of UCXBs have HeWD donors, 15% - 40% of UCXBs have COWD donors and UCXBs with ONeWD indicates that the uncertainty mainly comes which develops in these systems. donors are negligible. Our investigation from evolution of the common-envelope

关键词： binaries: close -- stars: neutron -- X-rays: binaries

Evaluation of strongly singular domain integrals for internal stresses in functionally graded materials analyses using RIBEM

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Acta Mechanica Sinica 2014年第6期30卷 917-926页

作者： Hai-Feng Peng Jian Liu Qiang-hua zhu Ch.Zhang School of Aeronautics and Astronautics Faculty of Vehicle Engineering and MechanicsDalian University of Technology Department of Civil Engineering University of Siegen D-57068 Siegen Germany

An accurate evaluation of strongly singular domain integral appearing in the stress representation formula is a crucial problem in the stress analysis of functionally graded materials using boundary element *** solve this problem,a singularity separation technique is presented in the paper to split the singular integral into regular and singular parts by subtracting and adding a singular *** singular domain integral is transformed into a boundary integral using the radial integration *** expressions of the radial integrals are obtained for two commonly used shear moduli varying with spatial *** regular domain integral,after expressing the displacements in terms of the radial basis functions,is also transformed to the boundary using the radial integration ***,a boundary element method without internal cells is established for computing the stresses at internal nodes of the functionally graded materials with varying shear modulus.

关键词： Stress integral equations Functionally graded materials Strongly singular domain integral Singularity separation technique Radial integration method

Contribution of dust produced by binary merger ejecta

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Research in Astronomy and Astrophysics 2015年第1期15卷 55-63页

作者： Zhao-Jun Wang Chun-hua zhu Guo-Liang Lü School of Physical Science and Technology Xinjiang University

By means of a population synthesis code and by constructing a simple toy model of dust produced by asymptotic giant branch（AGB） stars, common envelope（CE） ejecta and binary merger ejecta, we estimate the dust product rates（DPRs） of these processes in the Milky Way. The total DPR from AGB stars is～ 6.7 × 10-4M yr-1, in which about 73% of dust grains are carbon, 24% are silicates and 3% are iron. The total DPR from CE ejecta is ～ 4.2 × 10-4M yr-1, in which about 83% of dust grains are silicates, about 12% are carbon and 5% are *** DPR from binary merger ejecta is less than 1/3 that from AGB stars or CE ejecta,and it could even be negligible under certain circumstances. Therefore, compared with AGB stars and CE ejecta, the contribution of dust produced by binary merger ejecta to total dust grains in the Milky Way is smaller or can be negligible.

关键词： binaries: close stars: evolution circumstellar matter dust