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AFFECTING PROCESS OF EXPLOSION IN ROCK MASS BY CYLINDRICAL CHARGE

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Transactions of Nonferrous Metals Society of China 1992年第3期2卷 25-29页

作者： zhang qi Xi'an Mining Institute Xi'an 710054China

The explosion effects and physical process in rock mass by cylindrical charges are *** maximum explosion cavity radius and the coefficient of effective explosion work are found through mechanical model and numerical *** dependance of explosion parameters on time is *** results show that the maximum explosion cavity radius produced by cylindrical charge of ammonium trinitro-toluene No.2 explosive in limestone and diabase is 1.50 and 1.26 times respectively as much as that of blasthole;and the coefficient of effective explosion work is 0.71 and 0.54 respectively as much as that of the blasthole.

关键词： explosion cavity blasting in rock mass explosion effect

Unsupervised GRNN flood mapping approach combined with uncertainty analysis using bi-temporal Sentinel-2 MSI imageries

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International Journal of Digital Earth 2021年第11期14卷 1561-1581页

作者： qi zhang Penglin zhang Xudong Hua School of Remote Sensing and Information Engineering Wuhan UniversityWuhanPeople’s Republic of China Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhenPeople’s Republic of China

Floods occur frequently *** timely,accurate mapping of the flooded areas is an important ***,an unsupervised approach is proposed for automated flooded area mapping from bitemporal Sentinel-2 multispectral images in this ***,spatial–spectral features of the images before and after the flood are extracted to construct the change magnitude image(CMI).Then,the certain flood pixels and non-flood pixels are obtained by performing uncertainty analysis on the CMI,which are considered reliable classification ***,Generalized Regression Neural Network(GRNN)is used as the core classifier to generate the initial flood ***,an easy-toimplement two-stage post-processing is proposed to reduce the mapping error of the initial flood map,and generate the final flood *** from other methods based on machine learning,GRNN is used as the classifier,but the proposed approach is automated and unsupervised because it uses samples automatically generated in uncertainty analysis for model *** of comparative experiments in the three sub-regions of the Poyang Lake Basin demonstrate the effectiveness and superiority of the proposed ***,its superiority in dealing with uncertain pixels is further proven by comparing the classification accuracy of different methods on uncertain pixels.

关键词： Unsupervised flood mapping optical remote sensing image spatial–spectral feature extraction uncertainty analysis GRNN Sentinel-2

Overhead supplemental far-red light stimulates tomato growth under intra-canopy lighting with LEDs

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Journal of Integrative Agriculture 2019年第1期18卷 62-69页

作者： zhang Ya-ting zhang Yu-qi YANG qi-chang LI Tao Key Laboratory of Energy Conservation and Waste Management of Agricultural Structures Ministry of Agriculture and Rural Affairs/Institute of Environment and Sustainable Development in AgricultureChinese Academy of Agriculture Sciences

Far-red(FR) light regulates phytochrome-mediated morphological and physiological plant *** study aims to investigate how greenhouse tomato morphology and production response to different durations of FR light during daytime and at the end of day(EOD).High-wire tomato plants were grown under intra-canopy lighting consisting of red(peak wavelength at 640 nm) and blue(peak wavelength at 450 nm) light-emitting diodes(LEDs) with photosynthetic photon flux density(PPFD) of 144 μmol m–2 s–1 at 10 cm away from the lamps,and combined with overhead supplemental FR light(peak wavelength at 735 nm) with PPFD of 43 μmol m–2 s–1 at 20 cm below the *** were exposed to three durations of FR supplemental lighting including: 06:00–18:00(FR12),18:00–19:30(EOD-FR1.5),18:00–18:30(EOD-FR0.5),and control that without supplemental FR *** results showed that supplemental FR light significantly stimulated stem elongation thereby resulting in longer plants compared with the ***,FR light altered leaf morphology toward higher leaf length/width ratio and larger leaf *** altered plant architecture in FR supplemented plants led to a more homogeneous light distribution inside the *** plant biomass was increased by 9–16% under supplemental FR light in comparison with control,which led to 7–12% increase in ripe fruit *** sugar content of the ripe tomato fruit was slightly decreased by longer exposure of the plants to FR *** matter partitioning to different plant organs were not substantially affected by the FR light *** significant differences were observed among the three FR light treatments in plant morphology as well as yield and biomass *** conclude that under intra-canopy lighting,overhead supplemental FR light stimulates tomato growth and *** supplementary of EOD-FR0.5 is more favorable,as it consumes less electricity but induces similar effects on plant morphology and yield.

关键词： Solanum lycopersicum far-red light LEDs intro-canopy lighting morphology yield

Tendencies of alloyed engineering in BiOX-based photocatalysts:a state-of-the-art review

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Rare Metals 2024年第4期43卷 1488-1512页

作者： Yan-Dong Sun Chao Zeng Xue zhang Zi-qi zhang Bo Yang Sheng-qi Guo Tianjin Key Laboratory of Clean Energy and Pollutant Control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China State-Province Joint Engineering Laboratory of Zeolite Membrane Materials Institute of Advanced MaterialsCollege of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation School of Physics and Electronic InformationAnhui Province Industrial Generic Technology Research Center for Alumics MaterialsHuaibei Normal UniversityHuaibei235000China

Energy-saving and environmentally friendly photocatalysis has emerged as a popular research area in response to issues with energy scarcity and environmental *** to the unique layer-like structure,BiOX(Cl,Br,I)is frequently used in ***,inherent flaws in BiOX,such as an inappropriate band gap and low carrier separation efficiency,restrict its capacity for *** to the tunable grouping layer,alloying engineering is employed to optimize the intrinsic properties of BiOX and alloyed BiOX becomes a promising photocatalytic *** review describes the structure of BiOX,where tunable halogen layers provide favorable conditions for the implementation of alloying engineering to improve intrinsic *** article compares the effects and mechanisms of alloying engineering on the optimization of the energy band structure and carrier behavior of BiOX,and lists various modification methods used to improve the optimization of the intrinsic properties by alloying engineering,including defect engineering,morphology control as well as the synergy between alloying and other modification methods(bismuth-rich strategies,cation doping,construction of heterojunctions and plasma resonance effects).Subsequently,applications of alloyed BiOX in energy and environmental fields are summarized,including contaminant degradation,antibacterial,CO_(2)reduction,nitrogen fixation and organic ***,we summarize the current challenges and future directions of alloyed *** is expected that this work will provide guidance and assistance for an in-depth study and understanding of the mechanisms of alloying engineering to optimize intrinsic properties and design alloyed BiOX with higher photocatalytic activity.

关键词： Bismuth oxyhalide Photocatalytic Alloyed engineering Microstructural regulation Application

A GENERALIZED QUASI-NEWTON EQUATION AND COMPUTATIONAL EXPERIENCE

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Journal of Computational Mathematics 2006年第5期24卷 665-674页

作者： Lei-hong zhang Ping-qi Pan Department of Mathematics Southeast University Nanjing 210096 China

The quasi-Newton equation has played a central role in the quasi-Newton methods for solving systems of nonlinear equations and/or unconstrained optimization problems. Insteady Pan suggested a new equation, and showed that it is of the second order while the traditional of the first order, in certain approximation sense [12]. In this paper, we make a generalization of the two equations to include them as special cases. The generalized equation is analyzed, and new updates are derived from it. A DFP-like new update outperformed the traditional DFP update in computational experiments on a set of standard test problems.

关键词： System of nonlinear equations, Unconstrained optimization, Quasi-Newtone quation Second-order Quasi-Newton equation, Update formula.

Influence of the Spudcan Angle on the Ultimate Bearing Capacity of Jack-up Platform

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China Ocean Engineering 2018年第4期32卷 476-481页

作者： zhang qi-yi LIU Zhi-jie Department of Ocean Engineering College of EngineeringOcean University of ChinaQingdao 266100China Key Laboratory of Ocean Engineering of Shandong Province Qingdao 266100China

Jack-up platforms of the Ocean engineering structures always withstand the vertical gravity loads which are applied to the seabed by spudcan, so it is important to determine the bearing capacity and the penetration depth of the spudcan for its geometry. In fact, it is up to the deformation law and the failure modes of soil surrounding the spudcan which can calculate the ultimate bearing capacity of the spudcan foundation on the soil seabed. By using the finite element analysis software Abaqus, the deformation law of soil around the spudcan is analyzed in detail, and the failure modes of soil surrounding the spudcan foundation are achieved. At the same time, based on the limit equilibrium theory, by use of static permissible slip-line field, the ultimate bearing capacity of the spudcan foundation is analyzed and the lower limit solution is derived theoretically, and the effect of the spudcan angle on the ultimate bearing capacity is investigated. The numerical results are compared with those obtained by the theoretical formulas deduced in this paper. On the basis of the lower limit solutions in this paper, the effect of the spudcan angle on the ultimate bearing capacity is revealed, and a practical bearing capacity formula is given to take the effect of the spudcan angle into consideration.

关键词： spudcan lower limit analysis ultimate bearing capacity failure modes Abaqus

Time-triggered State-machine Reliable Software Architecture for Micro Turbine Engine Control

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Chinese Journal of Aeronautics 2012年第6期25卷 839-845页

作者： zhang qi XU Guoqiang DING Shuiting School of Transportation Science and Technology Beihang University Beijing 100191 China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Beihang University Beijing 100191 China

Time-triggered （TT） embedded software pattern is well accepted in aerospace industry for its high reliability. Fi-nite-state-machine （FSM） design method is widely used for its high efficiency and predictable behavior. In this paper, the time-triggered and state-machine combination software architecture is implemented for a 25 kg thrust micro turbine engine （MTE） used for unmanned aerial vehicle （UAV） system; also model-based-design development workflow for airworthiness software directive DO-178B is utilized. Experimental results show that time-triggered state-machine software architecture and development method could shorten the system development time, reduce the system test cost and make the turbine engine easily comply with the airworthiness rules.

关键词： airworthiness time-triggered finite-state-machine model-based-design turbine engine control

Corrosion Inhibition of SiCp/5A06 Aluminum Metal Matrix Composite by Cerium Conversion Treatment

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Chinese Journal of Aeronautics 2009年第6期22卷 670-676页

作者： Irfan Aziz zhang qi Xiang Min School of Materials Science and Engineering Beo'ing University of Aeronautics and Astronautics Beijing 100191 China

This article studies the effects of the CeCl3 concentrations in conversion solutions with and without addition of NaCl, pH-values of conversion solution, drying temperature, time and temperature of immersion on the Ce-conversion coatings for corrosion protection of the SiCp/5A06 Al-MMC and 5A06 Al-alloy in the 3.5% NaCl aqueous solution at room temperature. Potentiodynamic polarization tests reveal that the Ce-conversion treatment could markedly improve the pitting corrosion resistance of the composite and the matrix alloy in chloride containing environment. The best corrosion resistance effects are obtained for the samples treatment in 1% CeCl3.7H2O/3.5% NaCl solution at 45℃ for 60 min, followed by drying at 100 ℃ for 30 min. Examinations by means of scanning electron microscopy （SEM）, energy dispersion spectroscopy （EDS） and X-ray photoelectron spectroscopy （XPS） indicate that this behavior is due to the precipitation of Ce-oxides/hydroxides on the cathodic intermetallics and the Al-oxide film on the rest of the metal matrix.

关键词： cerium thermal coatings SiCp/5A06 Al matrix composites potentiodynamic polarization alkaline corrosion

Machine Learning is Accelerating Materials Research

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材料导报 2020年第9期34卷 1-2页

作者： zhang qi ZHENG Yujie SUN Kuan MOE Key Laboratory of Low-grade Energy Utilization Technologies and Systems CQU-NUS Renewable Energy Materials&Devices Joint LaboratorySchool of Energy&Power EngineeringChongqing UniversityChongqing 400044China

The development of artificial intelligence is reshaping our human *** a branch of artificial intelligence,machine learning can learn from existing data and establish correlations between input data and the *** performance of the model can be improved through training,helping us to discover hidden laws in the *** has been made in applying machine learning to the field of materials science[1].For example,machine lear-ning is employed to establish the structure-property relationship in various material systems[2-3],quickly screen new materials[4-5],discover novel structures[6]and optimize experimental parameters[7],*** seems machine learning is revolutionizing the way of materials research by providing new approaches to materials design,synthesis,characterization,and application[8].

关键词： branch applying intelligence