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辐射研究与辐射工艺学报 1989年第2期7卷 51-56页

作者：刘立明唐传道彭光剑蓝俊明湖南省原子能农业应用研究所

本文采用^(60)Coγ射线辐照“尾张”品种的果实,于1983～1986年连续进行了贮藏效果、辐照工艺以及果实品质等方面的研究,结果表明用厚度为0.015mm的聚乙烯膜单果包装、20—50Gy剂量辐照处理温州蜜柑有较好的贮藏保鲜效果。

关键词：蜜柑钻辐射 γ射线贮藏保鲜

150 mm×150 mm小方坯超低碳钢H1T生产实践

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特殊钢 2024年第6期45卷 17-22页

作者：陈军彭光健林丹黄振华湖南华菱湘潭钢铁有限公司湘潭410111

针对超低碳钢H1T传统的预处理-转炉-RH-大方坯连铸/模铸-开坯工艺生产成本高,以及连铸浇注过程中容易发生堵塞水口导致生产中断的问题,开发了150 mm×150 mm方坯连铸生产工艺,重点针对连铸水口结瘤堵塞进行工艺控制,并对生产过程中化学... 详细信息

针对超低碳钢H1T传统的预处理-转炉-RH-大方坯连铸/模铸-开坯工艺生产成本高,以及连铸浇注过程中容易发生堵塞水口导致生产中断的问题,开发了150 mm×150 mm方坯连铸生产工艺,重点针对连铸水口结瘤堵塞进行工艺控制,并对生产过程中化学成分、渣系、夹杂物变化进行分析。工业生产表明,采用转炉出钢加铝脱氧、LF渣碱度>10,顶渣(FeO+MnO)≤2%,搅拌氩气流量>600 L/min确保脱硫、RH工序在65 Pa以下吹氧深脱碳、钢水钙处理等工艺优化,成功生产出超低碳钢H1T产品,并且连浇炉数达到10炉次。

关键词：超低碳钢炉外精炼顶渣改质钙处理方坯

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耐蚀冷镦钢X08NH的钢坯加热工艺研究

金属材料与冶金工程 2019年第4期47卷 24-30页

作者：罗卫国彭光健杨瑞文陈立湖南华菱湘潭钢铁有限公司

Cu元素能提高钢材的耐蚀性,但会使钢材产生铜脆缺陷。对耐蚀冷镦钢X08NH钢坯高温加热时铜脆缺陷影响因素进行研究,为找到铜脆缺陷产生的原因,采用金相检验、能谱分析、冷镦检验等手段对缺陷试样进行了观察和分析。结果表明:由于Cu的熔点... 详细信息

Cu元素能提高钢材的耐蚀性,但会使钢材产生铜脆缺陷。对耐蚀冷镦钢X08NH钢坯高温加热时铜脆缺陷影响因素进行研究,为找到铜脆缺陷产生的原因,采用金相检验、能谱分析、冷镦检验等手段对缺陷试样进行了观察和分析。结果表明:由于Cu的熔点低,钢坯加热时,过高的钢坯出炉温度、过长的加热时间容易使钢坯表面形成Cu富集,降低晶间强度,产生晶间开裂,形成铜脆缺陷。通过对钢坯加热工艺的研究,最终解决了钢坯加热过程中产生铜脆缺陷的问题。

关键词： X08NH 铜脆冷镦钢加热工艺

大规格SCM440钢冷镦开裂原因分析及改进

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金属材料与冶金工程 2018年第4期46卷 27-32,42页

作者：罗卫国杨瑞文彭光健陈立湖南华菱湘潭钢铁有限公司湖南湘潭411101

针对国内某用户在使用某公司的大规格中碳合金冷镦钢SCM440盘条生产12.9级高强内六角螺栓时出现螺栓头部开裂的不良情况,我们采用金相检验、能谱分析等手段对开裂试样进行了观察和分析。结果表明:冷镦开裂是由于盘条表面划伤、裂纹、折... 详细信息

针对国内某用户在使用某公司的大规格中碳合金冷镦钢SCM440盘条生产12.9级高强内六角螺栓时出现螺栓头部开裂的不良情况,我们采用金相检验、能谱分析等手段对开裂试样进行了观察和分析。结果表明:冷镦开裂是由于盘条表面划伤、裂纹、折叠等表面质量缺陷所致。针对盘条表面存在的质量缺陷问题,通过优化炼钢保护渣性能、改善炼钢工艺、改造高线工艺设备、加强对高线导卫和导槽等工艺设备的监管检查和更换、增加头尾的剪切量,最终解决了盘条冷镦开裂的问题。

关键词：大规格 SCM440 冷镦开裂表面质量缺陷

窦口鼻道复合体变异与鼻中隔偏曲及鼻旁窦炎相关性的CT影像研究

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中华放射学杂志 2018年第4期52卷 252-256页

作者：杨晓霞唐光健南喜文彭泰松于萍武金龙贾夏青赵丽丽杨生伟山西省大同市第三人民医院放射科 037008 北京大学第一医院放射科

目的探讨窦口鼻道复合体（OMC）变异与鼻中隔偏曲、鼻旁窦炎的相关性。方法回顾性分析2015年6月1日至2016年5月30日行鼻与鼻旁窦CT检查的256例患者的临床与影像资料，鼻旁窦骨折、肿瘤及图像有伪影者不纳入研究，于半月裂水平行冠状面... 详细信息

目的探讨窦口鼻道复合体（OMC）变异与鼻中隔偏曲、鼻旁窦炎的相关性。方法回顾性分析2015年6月1日至2016年5月30日行鼻与鼻旁窦CT检查的256例患者的临床与影像资料，鼻旁窦骨折、肿瘤及图像有伪影者不纳入研究，于半月裂水平行冠状面多平面重建进行观察。将患者先按有无鼻中隔偏曲分为两组，采用两独立样本χ2检验分析两组间OMC变异的发生率、单双侧变异的发生率及鼻旁窦炎发生率、单双侧鼻旁窦炎发生率的差异，再按有无OMC变异分为两组，比较两组间鼻旁窦炎发生率、单双侧鼻旁窦炎发生率的差异。结果鼻中隔偏曲组96例，鼻中隔无偏曲组160例，两组间OMC变异率的差异有统计学意义（χ2=38.40，P〈0.05），且两组间单、双侧OMC变异率的差异有统计学意义（χ2=13.70，P〈0.05），单侧OMC变异位于偏曲同侧者92.6%（50/54）；两组间鼻旁窦炎发生率的差异无统计学意义（χ2=0.50，P〉0.05），且两组间单、双侧鼻旁窦炎发生率的差异亦无统计学意义（χ2=2.25，P〉0.05）。256例中，OMC变异者128例，无OMC变异者128例，两组间鼻旁窦炎发生率的差异无统计学意义（χ2=0.56，P〉0.05），且两组间单、双侧鼻旁窦炎发生率的差异亦无统计学意义（χ2=3.57，P〉0.05）。结论鼻中隔偏曲鼻腔增宽侧OMC变异可能是对鼻腔增宽的一种代偿，而不是鼻旁窦炎发生的阻塞因素。

关键词：窦口鼻道复合体鼻中隔偏曲鼻旁窦炎

中国文化情境下价值感知对农户混农林低碳增汇措施采纳的影响

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西北农林科技大学学报（社会科学版） 2025年第1期25卷 78-88页

作者：薛彩霞侯广健西北农林科技大学经济管理学院陕西杨凌712100

混农林是高效利用自然资源、减缓气候变化的生态农业模式,农户的混农林低碳增汇措施对其贡献“双碳”目标具有重要影响。基于陕南秦巴山区864份调研数据,运用多元Probit模型以及调节效应模型探讨中国文化情境下价值感知对农户混农林低... 详细信息

混农林是高效利用自然资源、减缓气候变化的生态农业模式,农户的混农林低碳增汇措施对其贡献“双碳”目标具有重要影响。基于陕南秦巴山区864份调研数据,运用多元Probit模型以及调节效应模型探讨中国文化情境下价值感知对农户混农林低碳增汇措施采纳的影响,并分析不同措施之间的关联效应以及社会权威的调节作用。结果表明:(1)农户的减少含碳要素投入与减少非合意产出、减少含碳要素投入与提高经营强度、减少含碳要素投入与加强森林保护以及提高经营强度与加强森林保护措施之间均存在互补效应;(2)功利感知对各低碳增汇措施均具有显著正向影响,合群感知对减少含碳要素投入具有显著正向影响,颜面感知对减少含碳要素投入和提高经营强度具有显著正向影响;(3)社会权威在合群感知、颜面感知与减少含碳要素投入,功利感知、颜面感知与提高经营强度,功利感知与加强森林保护的关系中起负向调节作用。建议政府从中国本土文化特征入手,激发农户响应“双碳”目标的内生力量,同时发挥不同措施与技术之间的协同效应,推动农林减排增汇的长效开展。

关键词：陕南秦巴山区价值感知中国农村社会特征混农林关联效应

湘钢汽车用XSWRCH10A-Q冷镦钢的开发

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金属材料与冶金工程 2018年第2期46卷 18-23页

作者：彭光健杨瑞文罗卫国陈立陈煜海湖南华菱湘潭钢铁有限公司湖南湘潭411101 安徽工业大学材料科学与工程学院安徽马鞍山243002

XSWRCH10A牌号冷镦钢在汽车行业当中主要用来生产底盘管类金属配件,鼓型件等异形件。产品变形量大,要求原材料具有较好的冷镦性能以及表面质量。本文介绍了湘钢汽车用XSWRCH10A-Q冷镦钢的开发,通过设计合适的XSWRCH10A-Q化学成分与生产... 详细信息

XSWRCH10A牌号冷镦钢在汽车行业当中主要用来生产底盘管类金属配件,鼓型件等异形件。产品变形量大,要求原材料具有较好的冷镦性能以及表面质量。本文介绍了湘钢汽车用XSWRCH10A-Q冷镦钢的开发,通过设计合适的XSWRCH10A-Q化学成分与生产工艺路线,最终生产的盘条冷镦性能良好,表面质量稳定。用户使用结果表明,汽车用XSWRCH10A-Q冷镦钢盘条能够满足生产汽车异形件的各项指标要求。

关键词：冷镦钢 XSWRCH10A-Q 冷镦性能表面质量

Quantification of occlusions influencing the tree stem curve retrieving from single-scan terrestrial laser scanning data

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Forest Ecosystems 2019年第4期6卷 285-297页

作者： peng Wan Tiejun Wang Wuming Zhang Xinlian Liang Andrew K.Skidmore guangjian Yan State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of Sciences Beijing Engineering Research Centre for Global Land Remote Sensing Products Institute of Remote Sensing Science and Engineering Faculty of Geographical Science Beijing Normal University

Background: The stem curve of standing trees is an essential parameter for accurate estimation of stem *** study aims to directly quantify the occlusions within the single-scan terrestrial laser scanning(TLS) data,evaluate its correlation with the accuracy of the retrieved stem curves, and subsequently, to assess the capacity of single-scan TLS to estimate stem ***: We proposed an index, occlusion rate, to quantify the occlusion level in TLS data. We then analyzed three influencing factors for the occlusion rate: the percentage of basal area near the scanning center, the scanning distance and the source of occlusions. Finally, we evaluated the effects of occlusions on stem curve estimates from single-scan TLS ***: The results showed that the correlations between the occlusion rate and the stem curve estimation accuracies were strong(r = 0.60–0.83), so was the correlations between the occlusion rate and its influencing factors(r = 0.84–0.99). It also showed that the occlusions from tree stems were the main factor of the low detection rate of stems, while the non-stem components mainly influenced the completeness of the retrieved stem ***: Our study demonstrates that the occlusions significantly affect the accuracy of stem curve retrieval from the single-scan TLS data in a typical-size(32 m × 32 m) forest plot. However, the single-scan mode has the capacity to accurately estimate the stem curve in a small forest plot(< 10 m × 10 m) or a plot with a lower occlusion rate, such as less than 35% in our tested datasets. The findings from this study are useful for guiding the practice of retrieving forest parameters using single-scan TLS data.

关键词： Stem curve Stem volume Terrestrial laser scanning Scan mode

Simulation of Shallow Gas Invasion Process During Deepwater Drilling and Its Control Measures

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Journal of Ocean University of China 2022年第3期21卷 707-718页

作者： LEI Yani SUN Jin WANG guangjian Department of Energy and Chemical Engineering Qingdao University of Science and TechnologyQingdao266525China Laboratory of Marine Geophysics and Georesource Institute of Deep-Sea Science and EngineeringChinese Academy of SciencesSanya572000China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519080China

Shallow gas is considered one of the most serious geological hazards in deepwater drilling because it has the characteristics of suddenness and is difficult to deal *** perform a quantitative evaluation of shallow gas risk during deepwater drilling,a numerical model for calculating gas invasion volume is established based on gas-water two-phase flow *** model considers the effect of the dynamic drilling process,and the influencing factors which affect the gas invasion volume are *** indicate that the gas invasion rate and accumulated gas invasion volume increase with increasing bottom-hole pressure difference.A linear relationship exists between gas invasion volume and bottom-hole pressure *** duration of gas invasion increases as the shallow gas zone thickness increases,and the accumulated gas invasion volume grows as shallow gas zone thickness *** increase in formation permeability,water depth,and rate of penetration will enhance the gas invasion ***,these three factors can hardly affect the accumulated gas invasion *** gas flow rate increases significantly with increasing burial depth of shallow *** the basis of influencing factor analysis,a series of methods that consider different risk levels is proposed to control shallow gas,which can provide a reference for the prevention of shallow gas disasters during deepwater drilling.

关键词： shallow gas deepwater drilling dynamic drilling process gas invasion gas invasion rate

Characteristics of the Main Journal Bearings of an Engine Based on Non-linear Dynamics

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Chinese Journal of Mechanical Engineering 2009年第5期22卷 755-759页

作者： NI guangjian ZHANG Junhong CHENG Xiaoming State Key Laboratory of Engine Tianjin University Tianjin 300072 China Tianjin Internal Combustion Engine Research Institute Tianjin 300072 China

Many simple nonlinear main journal bearing models have been studied theoretically, but the connection to existing engineering system has not been equally investigated. The consideration of the characteristics of engine main journal bearings may provide a prediction of the bearing load and lubrication. Due to the strong non-linear features in bearing lubrication procedure, it is difficult to predict those characteristics. A non-linear dynamic model is described for analyzing the characteristics of engine main journal bearings. Components such as crankshaft, main journals and con rods are found by applying the finite element method. Non-linear spring/dampers are introduced to imitate the constraint and supporting functions provided by the main bearing and oil film. The engine gas pressure is imposed as excitation on the model via the engine piston, con rod, etc. The bearing reaction force is calculated over one engine cycle, and meanwhile, the oil film thickness and pressure distribution are obtained based on Reynolds differential equation. It can be found that the maximum bearing reaction force always occurs when the maximum cylinder pressure arises in the cylinder adjacent to that bearing. The simulated minimum oil film thickness, which is 3 μm, demonstrates the reliability of the main journal bearings. This non-linear dynamic analysis may save computing efforts of engine main bearing design and also is of good precision and close connection to actual engine main journal bearing conditions.

关键词： non-linear dynamics engine main journal bearings