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Soft initial-rotation and H_∞ robust constant rotational speed control for rotational MEMS gyro

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Journal of Systems Engineering and Electronics 2009年第3期20卷 583-589页

作者： Ma Gaoyin Chen Wenyuan Cui Feng zhang Weiping Wang liqi National Key Lab. of Nano/Micro Fabrication Technology Key Lab. for Thin Film and Microfabrication of Ministry of Education Inst. of Micro and Nano Science and Technology Shanghai Jiaotong Univ.Shanghai 200240 P. R. China

A novel soft initiai-rotation control system and an H∞ robust constant rotational speed controller （RCRSC） for a rotational MEMS （micro-electro-mechanical system） gyro are presented. The soft initial-rotation control system can prevent the possible tumbling down of the suspended rotor and ensure a smooth and fast initial-rotation process. After the initial-rotation process, in order to maintain the rotational speed accurately constant, the RCRSC is acquired through the mixed sensitivity design approach. Simulation results show that the actuation voltage disturbances from the internal carrier waves in the gyro is reduced by more than 15.3 dB, and the speed fluctuations due to typical external vibrations ranging from 10 Hz to 200 Hz can also be restricted to 10^-3 rad/s order.

关键词： micro-electro-mechanicai system gyro rotation mixed sensitivity design H∞ robust controller

Magma Generation of Magnetite-Rich Intermediate-Mafic Rocks and Its Mantle Processes in the Southwestern Alxa Block,NW China

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Journal of Earth Science 2022年第1期33卷 161-176页

作者： Lu Tao Hongfei zhang Jing Wu Xiaochun Zhou liqi zhang State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Sciences China University of GeosciencesWuhan 430074China Gemmological Institute China University of GeosciencesWuhan 430074China Faculty of Earth Resources China University of GeosciencesWuhan 430074China

Many studies focus on mineralization of huge magnetite ore deposits and petrogenesis of their large-volume host ***,magma generation of those small-scale intrusions with enrichment of magnetite is poorly reported and paid attention *** here carry out an integrated study of magnetite chemistry,U-Pb zircon dating,geochemistry,and Sr-Nd-Hf isotopes for the magnetite-rich intermediate-mafic rocks from the Helishan pluton in the southwestern Alxa Block,Northwest ***,together with several previously reported magnetite/iron-rich intrusions nearby,is capable of providing some constraints on magma generation of magnetite/iron-rich intrusive *** Helishan pluton,dated at ca.290 Ma,consists of hornblende gabbro,diorite,and quartz monzodiorite with~3%-5%magnetite in all the *** on magnetite chemistry manifests a magmatic origin for *** the lithologies display high TFeO/MgO ratio (1.71-1.89),weakly fractionated REE patterns((La/Yb)_(N)=1.82-10.17),enrichment of Rb,Sr,and Pb,and depletion of high field strength *** have (^(87)Sr/^(86)Sr)_(i) values of 0.705 2 to 0.705 8,ε_(Nd)(t) values of+0.03 to+0.64,and zircon ε_(Hf)(t) values of +6.5 to+*** propose that they were derived from partial melting of iron-rich metasomatized lithospheric *** systematic variations of Sr/Y ratios and Nd-Hf isotopic compositions with time for the Paleozoic igneous rocks at the southwestern Alxa Block indicate ever existence of thinning and rebirth of lithospheric *** geodynamic process could be the potential mechanism to give rise to the iron-rich signature of the reborn mantle sources of the Helishan *** intermediatemafic intrusions at subduction zones,they are unlikely to form considerable magnetite ore deposits since their modest magmatic flux and early fractional crystallization of magnetite at a high oxygen fugacity and H_(2)O condition.

关键词： geochemishtry magnetite-rich intrusion mantle source petrogenesis lithospheric process Alxa Block Northwest China

Effect of different organic compounds on the preparation of CaO-based CO_(2) sorbents derived from wet mixing combustion synthesis

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Chinese Journal of Chemical Engineering 2021年第8期34卷 157-169页

作者： Tong Luo Shaolong Liu Cong Luo Xiaolei Qi Bowen Lu liqi zhang State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

CaO based sorbents have great potential for commercial use to capture CO_(2) of power *** the demand of producing sorbents with better cyclic performance,CaO-based sorbents derived from different kinds of calcium precursors,containing calcium carbonate(CC-CaO),calcium gluconate monohydrate(CG-CaO),calcium citrate(CCi-CaO)and calcium acetate monohydrate(CA-CaO),were tested cyclically and compared using simultaneous thermal analyzer(STA).And further study was conducted on the sorbents modified with citric acid monohydrate and 50%gluconic acid solution by wet mixing combustion *** modified sorbents showed better performance and higher pore parameters as well as porous microstructure with more organic acid *** 20 cycles of carbonation and calcination,the C2CCi8(CaO:citric acid=2:8 by mass ratio)and C2G8(CaO:gluconic acid=2:8 by mass ratio)sorbent possess CO_(2) capture capacity of 0.45g·g^(-1)(g CO_(2) per g sorbents)and 0.52 g·g^(-1) *** citric acid was more effective for modification than gluconic acid for extended 50 ***,good linear relationship between CaO conversion and specific surface area as well as pore volume were determined,of which the specific surface area showed closer correlation with CaO conversion。

关键词： CO_(2)capture Calcium precursors Wet mixing synthesis Organic additives

Experimental investigation on turbulence modification in a horizontal channel flow at relatively low mass loading

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Acta Mechanica Sinica 2006年第2期22卷 99-108页

作者： Yi Wu Hangfeng Wang Zhaohui Liu Jing Li liqi zhang Chuguang Zheng State Key Lab. Coal Combustion Huazhong Univ. of Sci. & Tech.Wuhan 430074 China

Particle-laden flows in a horizontal channel were investigated by means of a two-phase particle image velocimetry （PIV） technique. Experiments were performed at a Reynolds number of 6826 and the flow is seeded with polythene beads of two sizes, 60μm and 110μm. One was slightly smaller than and the other was larger than the Kolmogorov length scale. The particle loadings were relatively low, with mass loading ratio ranging from 5 ×10^-4 to 4 × 10^-2 and volume fractions from 6×10×-7 to 4.8×10^-5, respectively. The results show that the presence of particles can dramatically modify the turbulence even under the lowest mass loading ratio of 5 × 10^-4. The mean flow is attenuated and de- creased with increasing particle size and mass loading. The turbulence intensities are enhanced in all the cases concerned. With the increase of the mass loading, the intensities vary in a complicated manner in the case of small particles, indicating complicated particle-turbulence interactions; whereas they increase monotonously in the case of large particles. The particle velocities and concentrations are also given. The particles lag behind the fluid in the center region but lead in the wall region, and this trend is more prominent for the large particles. The streamwise particle fluctuations are larger than the gas fluctuations for both sizes of particles, however their varying trend with the mass loadings is not so clear. The wallnormal fluctuations increase with increasing mass loadings. They are smaller in the 60μm particle case but larger in the 110μm particle case than those of the gas phase. It seems that the small particles follow the fluid motion to certain extent while the larger particles are more likely dominated by their own inertia. Finally, remarkable non-uniform distributions of particle concentration are observed, especially for the large particles. The inertia of particles is proved to be very important for the turbulence modification and particles behaviors and thus

关键词： Horizontal channel Particle-laden flow Turbulence modification PIV

Development and Regeneration Performance of LaNiO_(3)Perovskite Oxides for Dry Reforming of Methane

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Journal of Thermal Science 2023年第5期32卷 1935-1944页

作者： CAO Dingshan LUO Cong CAI Guoqiu LUO Tong WU Fan LI Xiaoshan ZHENG Ying zhang liqi State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Dry reforming of methane(DRM)process has attracted much attention in recent years for the direct conversion of CH_4 and CO_(2)into high-value-added *** key for DRM was to develop catalysts with high activity and *** this study,LaNiO_(3)was prepared by the sol-gel,co-precipitation,and hydro-thermal methods to explore the influence of preparation methods on the catalyst structure and DRM reaction *** regeneration properties of the used LaNiO_(3)catalysts were also investigated under steam,CO_(2),and air atmospheres,*** results showed that LaNiO_(3)prepared by sol-gel method showed the best DRM performance at 750℃.The DRM performance of the samples prepared by hydro-thermal method was inhibited at 750℃due to the residual of Na^(+)ions during the preparation *** regeneration tests showed that none of the three atmospheres could restore LaNiO_(3)perovskite phase in the samples,but they could eliminate the carbon deposits in the samples during the DRM reaction,so the samples could maintain stable DRM performance at different cycling stages.

关键词： dry reforming of methane perovskite LaNiO_(3) CO_(2)utilization thermal conversion

Fundamental and Technical Challenges for a Compatible Design Scheme of Oxyfuel Combustion Technology

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Engineering 2015年第1期1卷 139-149页

作者： Chuguang Zheng Zhaohui Liu Jun Xiang liqi zhang Shihong zhang Cong Luo Yongchun Zhao State Key Laboratory of Coal Combustion Huazhong University of Science and Technology

Oxyfuel combustion with carbon capture and sequestration （CCS） is a carbon-reduction technology for use in large-scale coal-fired power plants. Significant progress has been achieved in the research and development of this technology during its scaling up from 0.4 MWth to 3 MWth and 35 aWth by the combined efforts of universities and industries in China. A prefeasibility study on a 200 MWe large-scale demonstration has progressed well, and is ready for implementation. The overall research development and demonstration （RD＆D） roadmap for oxyfuel combustion in China has become a critical component of the global RD＆D roadmap for oxyfuel combustion. An air combustion/oxyfuel combustion compatible design philosophy was developed during the RD＆D process. In this paper, we briefly address fundamental research and technology innovation efforts regarding several technical challenges, including combustion stability, heat transfer, system operation, mineral impurities, and corrosion. To further reduce the cost of carbon capture, in addition to the large-scale deployment of oxyfuel technology, increasing interest is anticipated in the novel and next- generation oxyfuel combustion technologies that are briefly introduced here, including a new oxygen-production concept and flameless oxyfuel combustion.

关键词： oxyfuel combustion research development anddemonstration CO2 capture

Migration and proliferation of ductal cells promote pancreatic repair after trauma

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Journal of Genetics and Genomics 2024年第11期51卷 1318-1321页

作者： Chaoqing Cheng Jinzi Chen liqi zhang Bangzhuo Huang Jianlong Ma Lingfei Luo Yun Yang Institute of Development Biology and Regenerative Medicine Southwest UniversityChongqing 400715China School of Life Sciences Fudan UniversityShanghai 200433China

Pancreatic trauma,commonly arising from blunt or penetrating injuries,poses clinical challenges due to its proneness to complications and the difficulty in trauma evaluation(Everson et al.,2023).Most current studies on pancreatic trauma primarily revolve around diagnostic and surgical advancements(Ayoob et al.,2021),with relatively little attention to the processes and mechanisms underlying pancreatic repair after trauma.

关键词： trauma injuries clinical

Characteristics of sulfate in atmosphere over Xiamen waters and its fluxes to waters

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Acta Oceanologica Sinica 1993年第4期12卷 585-595页

作者： Huang Ziqiang, zhang Yuanhui and Chen liqi Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China

One hundred and seven marine aerosol samples were collected during December 1988 to March 1990, and 3 dry deposition samples, 16 rain samples and 2 Cascade Impacter samples were collected from March to May 1990 at the southeast coast of the Xiamen Island. All the samples were analyzed for SO42-, NO3-, Cl-, Na+ , NH4+, using ion *** results indicate that the concentration of sulfate in marine aerosols over the Xiamen waters appears to be of seasonal variation, in an order of winter > spring > autumn > summer. The mean sulfate concentration lor the total marine aerosol samples over the Xiamen waters is 9. 37 μg/m3, respectively 0. 89 and 8. 48 μg/m3 for the seasalt and non-sea-salt sulfate. The distribution of sulfate shows a bimodal form with a peak in the coarse particle range which is derived from the sea-salt sulfate, and a peak in the fine particle range which is derived from the non-sea-salt sulfate. The total deposition of sulfate to the Xiamen waters is estimated to be 4. 68g/m2 · a, with dry and wet depositions being approximately 2.19 and 2. 49g/m2 · a respectively.

关键词： Sulfate marine aerosol Xiamen waters

A Note on the Inverse Connected p-Median Problem on Block Graphs

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Advances in Pure Mathematics 2023年第4期13卷 181-186页

作者： Chunsong Bai liqi zhang Jianjie Zhou School of Finance and Mathematics Huainan Normal University Huainan China Department of Information & Computational Science Henan Agricultural University Zhengzhou China

Recently, the inverse connected p-median problem on block graphs G(V,E,w) under various cost functions, say rectilinear norm, Chebyshev norm, and bottleneck Hamming distance. Their contributions include finding a necessary and sufficient condition for the connected p-median problem on block graphs, developing algorithms and showing that these problems can be solved in O(n log n) time, where n is the number of vertices in the underlying block graph. Using similar technique, we show that some results are incorrect by a counter-example. Then we redefine some notations, reprove Theorem 1 and redescribe Theorem 2, Theorem 3 and Theorem 4.

关键词： Location Theory Block Graphs Inverse Optimization Connected p-Median