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粉煤灰改良粉砂土动静力学特性研究

科学技术与工程 2024年第4期24卷 1619-1626页

作者：周桓锐崔高航程卓李琦张永珍闵子桐东北林业大学土木工程学院哈尔滨430070 河北工业大学土木与交通学院天津300401

为探究不同粉煤灰掺量粉砂土的动力特性和粉煤灰改良粉砂土的改性机理,以绥化—大庆高速公路路基填土为研究对象,开展无侧限压缩试验和动三轴试验,分析粉煤灰掺量对粉砂土静力学特征影响情况,以及围压、动荷载加载次数和粉煤灰掺量对改... 详细信息

为探究不同粉煤灰掺量粉砂土的动力特性和粉煤灰改良粉砂土的改性机理,以绥化—大庆高速公路路基填土为研究对象,开展无侧限压缩试验和动三轴试验,分析粉煤灰掺量对粉砂土静力学特征影响情况,以及围压、动荷载加载次数和粉煤灰掺量对改良粉砂土动强度的影响规律。结果表明:围压相同的情况下,土体的无侧限压缩强度和动强度,均随粉煤灰掺量增加先升高后降低;加载次数相同时,围压越大,土体动强度越大;选取加载次数为100次动强度进行拟合分析,得出粉煤灰掺入量与动剪切强度对应关系的经验公式。为改善路基强度,加快粉煤灰综合利用进程,结合试验结果与数据分析,建议在粉砂土路基掺加质量比15%粉煤灰进行路基施工。15%粉煤灰掺入量的改良粉砂土对比素土,存在颗粒紧凑,孔隙更小,结构相对致密,骨架更强等优点,可为东北地区粉砂土改良等工程建设提供参考。

关键词：粉煤灰改良粉砂土动静荷载综合作用动强度道路路基土定性分析

乙烯-乙酸乙烯酯共聚物热熔胶黏剂在长期热退火过程中的结晶行为

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高分子学报 2024年第11期55卷 1538-1548页

作者：陈阁王小黎梁晓凡张欢陈晓彤沈雷侯磊赵月史伟超南开大学功能高分子材料教育部重点实验室、化学学院高分子化学研究所天津300071 航天材料及工艺研究所北京100076

乙烯-乙酸乙烯酯共聚物(EVA)热熔胶黏剂(简称EVA热熔胶)是一种环保、综合性能优良的高分子材料,其储存和使用条件,尤其是温度和湿度等因素,影响着热熔胶黏剂中的晶体结构,最终影响其力学性能.为了探究结晶与力学性质之间的关系,本文中... 详细信息

乙烯-乙酸乙烯酯共聚物(EVA)热熔胶黏剂(简称EVA热熔胶)是一种环保、综合性能优良的高分子材料,其储存和使用条件,尤其是温度和湿度等因素,影响着热熔胶黏剂中的晶体结构,最终影响其力学性能.为了探究结晶与力学性质之间的关系,本文中选用热熔胶黏剂分别在干热、湿热等条件下进行长期热退火实验.研究发现,短时间热退火会导致热熔胶黏剂力学性能的缓慢提升.结合示差量热扫描分析实验结果表明,热熔胶黏剂的力学性能变化主要源于热退火对热熔胶黏剂结晶行为的促进作用.小角X射线散射实验表明,热退火对于晶区厚度并没有显著影响,但通过广角X射线散射实验,发现热退火主要促进晶体在(110)晶面的生长,对于(200)晶面的影响可以忽略.进一步地,通过偏振小角激光散射实验发现,热熔胶黏剂的球晶结构主要由热稳定形较好的片晶构成,在80℃以上的较高温度才能完全熔融.相比较而言,不完善的细小晶体在60℃以下就可以完全熔融,长期热退火可以有效消除热熔胶黏剂中的细小晶体.本文工作研究了热熔胶黏剂在高温或湿热环境中的结晶和力学性能关系,为优化热熔胶黏剂的储存和服役条件提供了实验依据.

关键词：乙烯-乙酸乙烯酯共聚物热熔胶黏剂热退火结晶散射

Denoising for satellite laser altimetry full-waveform data based on EMD-Hurst analysis

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International Journal of Digital Earth 2020年第11期13卷 1212-1229页

作者： Zhijie Zhang huan Xie Xiaohua tong Hanwei Zhang Yang Liu Binbin Li School of Surveying and Land Information Engineering Henan Polytechnic UniversityJiaozuoPeople’s Republic of China College of Surveying and Geo-Informatics and State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghaiPeople’s Republic of China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghaiPeople’s Republic of China College of Marine Science Shanghai Ocean UniversityShanghaiPeople’s Republic of China

Full-waveform decomposition is crucial for obtaining accurate satelliteground distance,the accuracy of which is severely affected by ***,the traditional filters all depend on filtering *** paper presents a new and adaptive method for denoising based on empirical mode decomposition(EMD)and Hurst analysis(EMD-Hurst).The noisy full-waveforms are first decomposed into their intrinsic mode functions(IMFs),and the Hurst exponent of each IMF is established by the detrended fluctuation *** IMF is regarded as the highfrequency noise and is deleted if its Hurst exponent is≤*** simulated and real full-waveforms were conducted to validate and evaluate the method by comparing with six other IMF selection methods via metrics like waveform decomposition consistency ratio(CR),average error of decomposition parameters,and ICESat/GLAS waveformparameter product *** comparisons show that:(1)under different SNR conditions,EMD-Hurst performs robustly and obtains a higher CR than other EMD based methods;(2)obtains the highest average CR and a relatively lower average error for the echo parameters;and(3)peak numbers and fitting accuracy for GLAH01 are more reasonable and precise than those of GLAH05,which could offer a good reference for the processing on future space-borne full-waveform data.

关键词： EMD-Hurst satellite laser altimetry full-waveform denoising IMF selection

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生物质汽化联产乙醇工艺路径研究

现代化工 2024年第2期44卷 32-36页

作者：莫志朋佟淑环宋庆坤张春悦贾伟北京首钢朗泽科技股份有限公司北京100043 河北首朗新能源科技有限公司河北省工业尾气发酵制乙醇技术创新中心河北唐山063200

介绍了生物质汽化制合成气在不同汽化剂条件下的主要气体组分,对合成气化学合成法及生物发酵法制乙醇路径进行了分析及比较,指出新型合成气发酵技术是具有工业化应用前景的生物质汽化合成气制乙醇工艺路径。

关键词：生物质汽化合成气乙醇发酵

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紫楠天然群落优势物种生态位与种间联结性

林业科学研究 2024年第3期37卷 61-67页

作者：陆云峰杨安娜王豪刘伟张俊红楼炉焕童再康浙江农林大学省部共建亚热带森林培育国家重点实验室浙江杭州311300 宁波市农业技术推广总站浙江宁波315012 丽水市森林资源保护管理总站浙江丽水323000

[目的]探究紫楠天然群落优势物种种间关系和群落稳定性。[方法]基于野外样地调查,从物种组成、重要值、生态位宽度、生态位重叠指数、方差比率法和χ^(2)检验等方面研究紫楠群落乔木层、灌木层各优势物种的生态位特征和种间联结性。[结... 详细信息

[目的]探究紫楠天然群落优势物种种间关系和群落稳定性。[方法]基于野外样地调查,从物种组成、重要值、生态位宽度、生态位重叠指数、方差比率法和χ^(2)检验等方面研究紫楠群落乔木层、灌木层各优势物种的生态位特征和种间联结性。[结果]紫楠在调查群落中的重要值最大,且其Levins指数生态位宽度和Shannon指数生态位宽度均最大,说明在群落中资源利用程度较高,竞争优势强;紫楠群落乔木层优势物种间总体呈不显著正联结(VR=1.247,χ^(2)_(0.95)(12)>W>χ^(2)_(0.05)(12)),而灌木层总体呈不显著负联结(VR=0.674,χ^(2)_(0.95)(36)>W>χ^(2)_(0.05)(36)),说明乔木层稳定性较高,且高于灌木层;χ^(2)检验结果显示乔木层、灌木层优势物种间正联结种对数均多于负联结,正负联结比分别为1.8∶1和1.5∶1,且绝大部分种对联结性均不显著,表明紫楠群落大多数优势物种间的生态特征较一致。[结论]紫楠群落总体稳定性较好,但仍可进行适当的人工抚育,促进紫楠种群自然更新。

关键词：紫楠天然群落优势物种生态位种间联结性

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Anthropogenic emission inventories in China:a review

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National Science Review 2017年第6期4卷 834-866页

作者： Meng Li huan Liu Guannan Geng Chaopeng Hong Fei Liu Yu Song Dan tong Bo Zheng Hongyang Cui Hanyang Man Qiang Zhang Kebin he Ministry of Education Key Laboratory for Earth System Modeling Department for Earth System Science Tsinghua University now at Max-Planck Institute for Chemistry State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University StateKey Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental SciencePeking University

The development of reliable anthropogenic emission inventories is essential for both understanding the sources of air pollution and designing effective air-pollution-control measures in China. However, it is challenging to quantify emissions in China accurately, given the variety of contributing sources, the complexity of the technology mix and the lack of reliable measurements. Over the last two decades,tremendous efforts have been made to improve the accuracy of emission inventories, and significant improvements have been realized. More reliable statistics and survey-based data have been used to reduce the uncertainties in activity rates and technology distributions. Local emission factors and source profiles covering various sources have been measured and reported. Based on these local databases, improved emission inventory models have been developed for power plants, large industrial plants and the residential,transportation and agricultural sectors. In this paper, we review the progress that has been made in developing inventories of anthropogenic emissions in China. We first highlight the major updates that have been made to emission inventory models and the underlying data by source category. We then summarize the sector-based estimates of emissions of different species contained in current inventories. The progress that has been made in the development of model-ready emissions is also presented. Finally, we suggest future directions for further improving the accuracy of emission inventories in China.

关键词： emission inventory atmospheric chemistry China chemical transport model air pollution

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基于动力吸振器的微耕机扶手架减振设计

农机化研究 2024年第3期46卷 92-97页

作者：刘欢尹宜勇王通王国强朱文佳齐林山李浩张伯伦中国农业大学工学院北京100083

微耕机的扶手架结构较为简单,在田间作业时会造成扶手架的强烈振动,长时间的强烈振动会给操作者身心带来不适甚至严重伤害,针对此问题,对微耕机扶手架进行了减振设计。对于结构相对简单的构件,振动问题大多是由于主振动系统自身结构阻... 详细信息

微耕机的扶手架结构较为简单,在田间作业时会造成扶手架的强烈振动,长时间的强烈振动会给操作者身心带来不适甚至严重伤害,针对此问题,对微耕机扶手架进行了减振设计。对于结构相对简单的构件,振动问题大多是由于主振动系统自身结构阻尼的不足导致的。为此,结合微耕机实际情况,将动力吸振器的设计方法应用于微耕机扶手架上,对动力吸振器进行结构设计并试制样件。最后,对动力吸振器样件的减振效果进行试验测试,结果表明:在安装动力吸振器样件后,其手把处的振动强度在空挡和耕作状态下分别降低了13.9%和11.2%。

关键词：微耕机扶手架减振设计动力吸振器

基于中医四诊仪探讨ARCOⅠ期激素性股骨头坏死患者的舌象特征

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内蒙古中医药 2024年第2期43卷 139-141页

作者：王欢郑志永赵杰董兴童山东中医药大学第一临床医学院山东济南250014 山东省中医院关节肿瘤科山东济南250014

目的:基于中医四诊仪客观探讨激素性股骨头坏死患者的高发舌象特征。方法:选取符合纳入标准的119例ARCOⅠ期激素性股骨头坏死患者作为观察组,利用中医四诊仪获取舌象信息,同样措施获取132例健康体检者的舌象信息作为对照组。比较两组舌... 详细信息

目的:基于中医四诊仪客观探讨激素性股骨头坏死患者的高发舌象特征。方法:选取符合纳入标准的119例ARCOⅠ期激素性股骨头坏死患者作为观察组,利用中医四诊仪获取舌象信息,同样措施获取132例健康体检者的舌象信息作为对照组。比较两组舌象信息。结果:本次共收集观察组119例,对照组132例。经过统计学检验,ARCOⅠ期激素性股骨头坏死患者与健康体检者相比,舌色、苔色、苔质具有统计学意义,有无瘀斑瘀点差异不具有统计学意义。与对照组相比,实验组的舌色偏于紫色,苔色偏于黄白相兼,苔质偏于厚腻。结论:本次研究发现ARCOⅠ期激素性股骨头坏死患者的舌象与健康体检者的舌象存在统计学差异。ARCOⅠ期激素性股骨头坏死患者的舌象与患者性别、年龄无明显相关性。

关键词：激素股骨头坏死舌象中医四诊仪

Recombinant helicoverpa armigera nucleopolyhedrovirus with arthropod-specific neurotoxin gene RjAa 17f from Rhopalurus junceus enhances the virulence against the host larvae

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Insect Science 2017年第3期24卷 397-408页

作者： huan Yu Bin Zhou Jiao Meng Jian Xu tong-Xian Liu Dun Wang State Key Laboratory of Crop Stress Biology for Arid Areas Northwest A&F UniversityYangling Shaanxi China Key Laboratory of Applied Entomology Northwest A&F UniversityYangling Shaanxi China

A recombinant helicoverpa armigera nucleopolyhedrovirus （hearNPV） ex- pressing the insect-selective neurotoxin （RjAalTjO from Cuban scorpion Rhopalurus junceus was constructed by replacing the UDP-glucosyltransferase gene （egt） using ）^- red homologous recombination system. Another egt deleted control hearNPV was con- structed in a similar way by inserting egfp gene into the egt locus. One-step viral growth curve and viral DNA replication curve analysis confirmed that the recombination did not affect the viral growth and DNA replication in host cells. There is no discernable differ- ence in occlusion-body morphogenesis between RjAalTf-hearNPV,, Egfp-hearNPV and HZ8-hearNPV, which was confirmed by transmission electron microscopy analysis. How- ever, the insecticidal activity of RjAal 7f-hearNPV is enhanced against the third instar H. armigera larvae according to the bioassay on virulence comparison. There is a dramatic reduction （56.9%） in median lethal dose （LD50） and also a reduction （13.4%） in median sur- vival time （ST50） for the recombinant RjAalTf-hearNPV compared to the HZ8-hearNPV, but only a 27.5% reduction in LD50 and 10.1% reduction in ST50 value when Egfp- hearNPV is compared with HZ8-hearNPV. The daily diet consumption analysis showed that the RjAal 7f-hearNPV was able to inhibit the infected larvae feeding compared with the egt minus hearNPV. These results demonstrated that this novel recombinant RjAa17f- hearNPV could improve the insecticidal effect against its host insects and RjAa17fcould be a considerable candidate for other recombinant baculovirus constructions.

关键词： hearNPV recombinant baculovirus RjAal 7f, virulence improvement