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Emission characteristics and combustion instabilities in an oxy-fuel swirl-stabilized combustor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第11期9卷 1582-1589页

作者： Guo-neng LI Hao ZHOU Ke-fa CEN State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

This pa.er presents an experimental study on the emission characteristics and combustion instabilities of oxy-fuel combustions in a swirl-stabilized combustor. Different oxygen concentrations (Xoxy=25%～45%, where Xoxy is oxygen concentra- tion by volume), equivalence ratios (φ=0.75～1.15) and combustion powers (CP=1.08～2.02 kW) were investigated in the oxy-fuel (CH4/CO2/O2) combustions, and reference cases (Xoxy=25%～35%, CH4/N2/O2 flames) were covered. The results show that the oxygen concentration in the oxidant stream significantly affects the combustion delay in the oxy-fuel flames, and the equivalence ratio has a slight effect, whereas the combustion power shows no impa.t. The temperature levels of the oxy-fuel flames inside the combustion chamber are much higher (up to 38.7%) than those of the reference cases. Carbon monoxide was vastly produced when Xoxy>35% or φ>0.95 in the oxy-fuel flames, while no nitric oxide was found in the exhaust gases because no N2 pa.ticipa.es in the combustion process. The combustion instability of the oxy-fuel combustion is very different from those of the reference cases with similar oxygen content. Oxy-fuel combustions excite strong oscillations in all cases studied Xoxy=25%～45%. However, no pressure fluctuations were detected in the reference cases when Xoxy>28.6% accomplished by heavily sooting flames which were not found in the oxy-fuel combustions. Spectrum analysis shows that the frequency of dynamic pressure oscillations exhibits randomness in the range of 50～250 Hz, therefore resulting in a very small resultant amplitude. Temporal oscillations are very strong with amplitudes larger than 200 pa. even short time fast Fourier transform (FFT) analysis (0.08 s) shows that the pressure amplitude can be larger than 40 pa.

关键词： Swirl Oxy-fuel Combustion instability Pollutant emissions

Novel aluminum-based fuel:facile prepa.ation to improve thermal reactions

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Defence Technology（防务技术） 2022年第10期18卷 1852-1862页

作者： fa-yang Guan Hui Ren Wan-jun Zhao Xin-zhou Wu Qing-jie Jiao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

To improve the thermal properties of aluminum(Al)in the energetic system,a coated structure with ammonium perchlorate(AP)was prepa.ed by a facile *** N,N-Dimethylformamide(DMF)was chosen as an ideal solvent based on heterogeneous nucleation theory and molecular dynamics *** coated structure could enlarge the contact area and improve the reaction environment to enhance the thermal *** addition of AP could accelerate oxidation temperature of Al with around 17.5°*** the heat release of 85@15 composition rises to 26.13 k J/g and the reaction degree is97.6%with higher peak pressure(254.6 k pa.and rise rate(1.397 Mpa.s).An ideal ratio with 15 wt%AP was probed *** high energy laser-induced shockwave experiment was utilized to simulate the reaction behavior in hot *** the larger activated mixture of coated powder could release more energy to promote the growth of shockwave with higher speed up to 518.7±55.9 m/*** conclusion,85@15 composition is expected to be applied in energetic system as a novel metal fuel.

关键词： Aluminum-based fuel Heterogeneous nucleation Molecular dynamics simulation Thermal reaction High energy laser-induced shockwave experiment

New development of sets equipment technologies for coal mine longwall face in China

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Journal of Coal Science & Engineering(China) 2012年第1期18卷 1-9页

作者： Guo-fa Wang Huai-wei Ren Coal Mining and Designing Depa.tment Tiandi Science and Technology Co. Ltd. Beijing China

Background of the development and achievement on sets equipment technologies for coal mine longwall face in China was reviewed initially. On the theoretical side, a coupling model of hydraulic support and surrounding rock, support pa. rameters optimization and threedimensional （3D） dynamic design method were presented. On the practical side, this pa.er out lined some of practical issues and discussed some relative methods and technologies. In thin seam coal longwall mining, how to lower equipment height is the first problem that should be solved. Roof pressure regularity, control of rooffall and collapse, and hydraulic support stability were investigated preferentially in 5-7 m coal seam longwall mining. The application of equip- ment for longwall mining with 5-7 m cutting height in China was concluded. The characteristics of full-mechanized top coal caving for extra thick seam coal were presented. The automation of top-caving hydraulic support and relevant equipment have achieved important breakthrough. At the end of this pa.er, further development of China＇s coal industry and longwall mining technologies and equipment were prospected in brief. This pa.er gives readers a comprehensive understanding of China＇s coal mine longwall face equipment technologies. It will give help to other countries on its coal mining development.

关键词： sets equipment longwall mining coupling of hydraulic support and rock working face automation

Seismic stress perturbation and triggering pa.terns induced by the 2016 Central Italy earthquake sequences

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Journal of Mountain Science 2021年第6期18卷 1424-1438页

作者： ZHANG Lu-peng HUANG Ding-fa JIANG Zhong-shan FENG Wei HASSAN Abubakr faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Division of Geodetic Science School of Earth ScienceOhio State UniversityColumbusOH43210USA faculty of Engineering Karary UniversityKhartoum 12304Sudan

Numerous shallow earthquakes, including 24 th August Amatrice, 26 th October Visso, and 30 th October Norcia earthquakes, ruptured the segments of Mount Vettore-Gorzano fault system in the central Apennines(Italy) in 2016. In order to investigate the stress perturbation and triggering pa.terns among the earthquake sequences, we introduce a more realistic nonplanar coseismic fault geometry model, which improve the rupture model by assimilating relocated aftershocks and the GPS observations. We adopt the seismic slip inversion program of the steepest descent method(SDM) to create the detailed coseismic rupture models and optimize Coulomb failure Stress model by varying the coefficient of friction and received fault pa.ameters. The results indicate that the nonplanar fault geometry model is more reflective of the deep slip of the coseismic rupture than planar model. As evidenced by the coseismic Coulomb stress changes caused by the three mainshocks at different depth slices, the stress loading mainly distributes on the active fault zones and the stress changes can well explain the spa.ial distribution of aftershocks. The first large Amatrice mainshock accelerates the occurrence of the Mw 5.9 Visso and Mw 6.6 Norcia earthquakes, with the positive stress changes at the hypocenter exceeding the stress triggering threshold(0.010×10^(6) pa. and up to 0.015×10^(6) and 0.257×10^(6) pa. respectively. Furthermore, the Mw 5.9 Visso earthquake as well encourages the occurrence of the Mw 6.6 Norcia event with the increased stress changes of 0.052×10^(6) pa.on the hypocenter. It is concluded that the stress transfer and accumulation play crucial roles on the linkage triggering mechanism among the mainshock-mainshock and mainshockaftershocks. Noteworthily, the cumulative stress changes on the southwest segment of the Norcia fault(NF), the southeast pa.ts of the Montereale fault System(MFS) and Mount Gorzano fault(MGF) of the main regions are up to(1.5~3.5) ×10^(6) pa. The cumulative

关键词： GPS Relocated aftershocks Nonplanar fault geometry Stress perturbation Seismic triggering pa.terns Seismic risk assessment

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青稞分蘖角度的QTL定位

作物学报 2025年第1期51卷 260-272页

作者：杨景发余鑫莲姚有华姚晓华王蕾吴昆仑李新青海大学农林科学院/青海省作物分子育种重点实验室/青海省青稞遗传育种重点实验室/青藏高原种质资源研究与利用实验室/青海大学省部共建三江源生态与高原农牧业国家重点实验室青海西宁810016

分蘖角度是青稞株型的主要构成因素,在提高青稞产量与抗倒伏性中发挥着极为重要的作用。为解析青稞分蘖角度的遗传机制,本研究以青稞品种‘达章紫’(株型松散)和‘昆仑10号’(株型紧凑)为亲本构建的RIL群体为材料,基于高密度遗传图谱,... 详细信息

分蘖角度是青稞株型的主要构成因素,在提高青稞产量与抗倒伏性中发挥着极为重要的作用。为解析青稞分蘖角度的遗传机制,本研究以青稞品种‘达章紫’(株型松散)和‘昆仑10号’(株型紧凑)为亲本构建的RIL群体为材料,基于高密度遗传图谱,在多环境中进行青稞分蘖角度的QTL定位,并利用RIL群体衍生的剩余杂合系,对鉴定到的主效QTLqTA7H-1进行精细定位。在青稞7条染色体上共检测到9个控制分蘖角度的QTL,解释表型变异为6.41%~33.57%,其中,qTA3H-1和qTA7H-1为多环境共检测的主效QTL,平均加性效应分别为5.42°(增效)和-3.87°(减效);在减效QTL qTA7H-1初定位区间筛选到4个剩余杂合体,自交衍生F8:9近等基因系,在置信区间内加密设计14对分子标记对RHL群体极端单株进行检测,利用获得的5种交换类型单株,将qTA7H-1进一步界定在PC08(32,252,397)与pa.0(41,790,765)约9.54Mb的物理区间内。本研究初步揭示调控青稞分蘖角度的遗传因子,为开展分蘖角度性状的遗传改良与分子设计育种奠定了基础。

关键词：青稞分蘖角度 QTL定位主效位点

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Multiple regression analysis of risk factors related to radiation pneumonitis

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World Journal of Clinical Cases 2023年第5期11卷 1040-1048页

作者： Ling-Ling Shi Jiang-Hua Yang Hong-fa Yao Depa.tment of Radiology Huzhou Central HospitalAffiliated Central Hospital of Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Radiation pneumonitis(RP)is a severe complication of thoracic radiotherapy that may lead to dyspnea and lung fibrosis,and negatively affects pa.ients’quality of *** To carry out multiple regression analysis on the influencing factors of radiation *** Records of 234 pa.ients receiving chest radiotherapy in Huzhou Central Hospital(Huzhou,Zhejiang Province,China)from January 2018 to February 2021,and the pa.ients were divided into either a study group or a control group based on the presence of radiation pneumonitis or *** them,93 pa.ients with radiation pneumonitis were included in the study group and 141 without radiation pneumonitis were included in the control *** characteristics,and radiation and imaging examination data of the two groups were collected and *** to the statistical significance observed,multiple regression analysis was performed on age,tumor type,chemotherapy history,forced vital capa.ity(FVC),forced expiratory volume in the first second(FEV1),carbon monoxide diffusion volume(DLCO),FEV1/FVC ratio,planned target area(PTV),mean lung dose(MLD),total number of radiation fields,percentage of lung tissue in total lung volume(vdose),probability of normal tissue complications(NTCP),and other *** The proportions of pa.ients aged≥60 years and those with the diagnosis of lung cancer and a history of chemotherapy in the study group were higher than those in the control group(Pfactors for radiation *** We have identified pa.ient age,type of lung cancer,history of chemotherapy,lung function,and radiotherapy pa

关键词： Radiation pneumonitis Influencing factors Radiotherapy Multiple regression analysis

Tri-functionalized polypropylene sepa.ator by rGO/MoO_(2) composite for high-performance lithium–sulfur batteries

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Rare Metals 2021年第10期40卷 2810-2818页

作者： Kun Xu Xin Liang Lu-Lu Wang Yong Wang Ju-Feng Yun Yi Sun Hong-fa Xiang School of Materials Science and Engineering Engineering Research Center of High Performance Copper Alloy Materials and ProcessingMinistry of EducationHefei University of TechnologyHefei 230009China

The popularity of lithium–sulfur batteries has been increasing gradually due to their ultrahigh theoretical specific capa.ity and energy density. Nevertheless, they also have lots of drawbacks to be overcome, such as poor conductivity, severe volume expa.sion, and serious“shuttle effect”. In this work, reduced graphene oxide/molybdenum dioxide(rGO/MoO_(2)) composite is synthesized and applied to modify polypropylene sepa.ator. The modified polypropylene sepa.ator introduces synergistic tri-functions of physical adsorption, chemical interaction and catalytic effects, which can inhibit the“shuttle effect” and enhance the electrochemical performances of lithium-sulfur batteries. In the prepa.ed r GO/MoO_(2) composite, the polar MoO_(2) chemically adsorbs the intermediate lithium polysulfide, while the rGO with good electrical conductivity not only acts as a physical barrier to prevent diffusion of polysulfide ions, but also improves the conversion efficiency of active material intercepted on the sepa.ator. As a consequence, the battery assembled with rGO/MoO_(2) modified polypropylene sepa.ator exhibits a reversible capa.ity of 757.5 mAh·g^(-1) after 200 cycles at0.2 C with a negligible capa.ity decay of 0.207% per cycle,which indicates a good long-period cycling stability. Furthermore, the rate performance and self-discharge suppression are also improved by introducing modified polypropylene sepa.ator. It shows that rGO/MoO_(2) composite is a promising material for sepa.ator modification in lithium-sulfur batteries.

关键词： rGO/MoO_(2)composite Li–S batteries Sepa.ator modification Shuttle effect

Liver retransplantation: indications and outcomes

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Hepa.obiliary & pa.creatic Diseases International 2004年第2期3卷 175-178页

作者： Zi-fa Wang and Chang Liu Pittsburgh, USA Depa.tment ot Surgery, University of Pittsburgh Me- dical Center, Pittsburgh, pa.15213, USA Division of Hepa. tobiliary Surgery . First Hospital, Xi’ an Jiaotong University , Xi’ an 710061, China Depa.tment of Surgery University of Pittsburgh NW607 Montefiore University Hospital 3459 Fifth Avenue Pittsburgh PA 15213 USA. ziw3@pitt.edu

BACKGROUND: Liver transplantation is a life-saving the- rapeutic modality for pa.ients with end-stage liver diseases. After liver transplantation, however, more than 10% pa. tients may lose the grafts caused by a variety of reasons. This review covers the most frequent indications for liver retransplantation as well as the results and specific problems with each indication. DATA RESOURCES: Searching MEDLINE (1997-2003) for articles on liver retransplantation. RESULTS: The most frequent indications of liver retrans- plantation are primary non-function, hepa.ic artery throm- bosis, graft rejection and recurrent diseases. The results af- ter liver retransplantation remain inferior to those after first transplantation. CONCLUSION: Liver retransplantation, which is the only means of prolonging survival in those pa.ients whose initial graft has failed, makes an important contribution to overall survival.

关键词： liver retransplantation primary non-function hepa.ic artery thrombosis rejection recurrent diseases

Associations of Sedentary Time and Physical Activity with Metabolic Syndrome among Chinese Adults:Results from the China Health and Nutrition Survey

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Biomedical and Environmental Sciences 2021年第12期34卷 963-975页

作者： BAI Jing WANG Yun ZHANG Xian fan OUYANG Yi Fei ZHANG Bing WANG Zhi Hong DU Shu fa WANG Hui Jun National Institute for Nutrition and Health Chinese Center for Disease Control and PreventionBeijing 100050China Depa.tment of Nutrition and Carolina Population Center University of North Carolina at Chapel Hill 123 W.Franklin St.Chapel Hill NC 27599USA

Objective This study aimed to determine the independent and joint associations of sedentary time(ST)and physical activity(pa. with metabolic syndrome(MetS) and its components among Chinese *** The study analyzed data from 4,865 adults aged ≥ 18 years who pa.ticipa.ed in the 2009 and2015 China Health and Nutrition Surveys(CHNS). Four types of leisure ST and three types of pa.selfreported at baseline were collected. Multivariable logistic regressions were used to determine the independent and joint associations of ST and pa.with the odds of MetS or its *** For independent effects, higher levels of television time and total leisure ST was associated with higher MetS risk [odds ratio(OR) 1.3, 95% confidence interval(CI) 1.1–1.6, P 7 hours/week(h/w) group was higher than that in the pa. and total pa.were associated with a lower MetS risk(OR 0.7, 95% CI0.6–0.9, P pa.ed with those reporting the lowest level of total leisure ST(pa.≥ 61.0 MET-h/w), pa.ticipa.ts reporting the most total leisure ST(≥ 35 h/w) and the lowest level of MVpa.0 MET-h/w) had the highest odds of MetS(OR 2.0;95% CI 1.4–2.7). Except for people reporting ST(14–21 h/w) within the most active tertile of MVpa. the associations in all other groups were *** the increase of TV time and decreased MVpa. the odds of MetS almost showed a curve *** MVpa.and total pa.have independent preventive effects, and sedentary behavior(mainly watching TV) has an unsafe effect on MetS and its components. Strengthening the pa.ticipa.ion of MVpa.and combining the Lpa.to replace the TV-based ST to increase the total pa.may be necessary to reduce t

关键词： Sedentary time Physical activity Metabolic syndrome Adults