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Frontiers of Environmental Science & Engineering 2020年第4期14卷 189-199页

作者： Yulu Qiu Zhiqiang Ma Weili Lin Weijun Quan Weiwei Pu Yingruo Li Liyan Zhou qingfeng shi Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China Beijing Shangdianzi Regional Atmosphere Watch Station Beijing 101507China Environmental Meteorology Forecast Center of Beijing-Tianjin-Hebei Beijing 100089China College of Life&Environmental Science Minzu University of ChinaBeijing 100081China

Peroxyacetyl nitrate(PA N)is one of the most important photochemical pollutants and has aroused much concern in China in recent ***,few studies described the long-term variations in PAN in *** this study,we continuously monitored the PAN,03 and NOx concentrations at a regional background site near Beijing from August 2015 to February *** on the observed concentrations and climate data,w e analyzed the seasonal PAN *** results revealed that the monthly mean PAN concentration ranged from 0.33-2.41 ppb,with an average value of 0.94 *** PAN concentration exhibited a distinct seasonal variation,with high values in spring and low values in *** analyzing the corresponding meteorological data,we found that stronger ultraviolet(UV)radiation,a relatively longer lifetime and a higher background PAN concentration contributed to the high PAN concentrations in *** addition,with the utilization of the WRF-Chem(Weather Research and Forecasting with Chemistry)model,the cause of the extremely high PAN concentration in spring 2018 wa s *** model results demonstrated that an anomalously low pressure and the southwesterly winds in northern China might be the main causes of the increased PAN concentration in Beijing and its surrounding area in spring 2018.

关键词： PAN Ozone Beijing WRF-Chem

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大型核电汽轮机推力轴承油膜失稳振动研究

动力工程学报 2019年第6期39卷 512-516页

作者：史庆峰中核核电运行管理有限公司

针对某些机型核电汽轮机出现轴向振动与径向振动耦合的现象,采用大型核电汽轮发电机组推力轴承可倾瓦块模型,对运行中油膜失稳引起的自激振动进行了机理分析。通过建立转子轴向运动方程,对某650 MW核电机组启机过程中推力轴承载荷进行... 详细信息

针对某些机型核电汽轮机出现轴向振动与径向振动耦合的现象,采用大型核电汽轮发电机组推力轴承可倾瓦块模型,对运行中油膜失稳引起的自激振动进行了机理分析。通过建立转子轴向运动方程,对某650 MW核电机组启机过程中推力轴承载荷进行了测量,计算得出不同轴向载荷和推力轴承间隙比条件下的油膜刚度和阻尼,并分析了推力轴承油膜失稳引起的转子轴向自激振动的频率特点。结果表明:轴向载荷、转速和油膜阻尼是引起推力轴承可倾瓦块轴向自激振动的主要因素;减小推力轴承间隙和增大润滑油压可以抑制转子轴向自激振动。

关键词：推力轴承可倾瓦块油膜失稳轴向自激振动

Variation in Sunshine Duration and Related Aerosol Influences at Shangdianzi GAW Station, China: 1958–2021

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Journal of Meteorological Research 2023年第4期37卷 551-563页

作者： Weijun QUAN Zhiqiang MA Ziming LI Xiaolan LI Yingruo LI Xiangao XIA Huaigang ZHOU Hujia ZHAO Zhenfa WANG Weiwei PU Fan DONG Di HE Liyan ZHOU qingfeng shi Wenyan WANG Fang JIA Beijing Weather Forecast Center Beijing Meteorological ServiceBeijing 100097 Environmental Meteorology Forecast Center of Beijing–Tianjin–Hebei Beijing Meteorological ServiceBeijing 100097 Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089 Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110116 Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029

Sunshine duration(SD) is adopted widely to study global dimming/brightening. However, long-term simultaneous measurements of SD and closely related impact factors require further analysis to elucidate how and why SD has varied during the past decades. In this study, a long-term(1958–2021) SD data series obtained from the Shangdianzi Global Atmosphere Watch(GAW) station in China was analyzed to detect linear trends, climatic jumps, and climatic periods in SD using linear fitting, the Mann–Kendall trend test, and the continuous wavelet transform method. Annual SD exhibited steady dimming(-67.3 h decade-1) before 2010, followed by a period of brightening(189.9 h decade-1)during 2011–2020. An abrupt jump in annual SD occurred in 1995, and the annual SD anomaly exhibited significant oscillation with ~3-yr periodicity during 1960–1978. Partial least squares analysis revealed that annual SD anomaly was associated with variations in relative humidity, gale days, cloud cover, and black carbon(BC). Further analysis of the clear-sky daily sunshine percentage(DSP) and simultaneous measurements of aerosol properties, including aerosol optical depth, aerosol extinction coefficient, single scattering albedo(SSA), BC, and total suspended particulates, suggested that variation in DSP was affected primarily by aerosol scattering and absorption. Furthermore, the hourly clear-sky SD at high aerosol loading was approximately 60% and 56% of that at middle and low aerosol loadings, respectively. The pattern of diurnal variation in clear-sky hourly SD, as well as the actual values, can be affected by the fine particulate concentration, aerosol extinction coefficient, and SSA.

关键词： sunshine duration global dimming/brightening multitemporal-scale variation partial least squares Shangdianzi

不同地膜覆盖对春玉米生长发育及水分利用效率的影响

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干旱区资源与环境 2017年第2期31卷 173-177页

作者：胡敏苗庆丰史海滨于庆峰内蒙古农业大学职业技术学院包头014109 内蒙古农业大学水利与土木建筑工程学院呼和浩特010018

为研究不同类型地膜覆盖在河套灌区农业生产中的适用性,同时筛选出适宜灌区玉米种植的地膜覆盖类型。试验设置普通地膜、生物地膜、液态地膜和不覆膜4个处理,研究了不同覆盖处理对玉米出苗率、生长状况、产量及水分利用效率的影响。结... 详细信息

为研究不同类型地膜覆盖在河套灌区农业生产中的适用性,同时筛选出适宜灌区玉米种植的地膜覆盖类型。试验设置普通地膜、生物地膜、液态地膜和不覆膜4个处理,研究了不同覆盖处理对玉米出苗率、生长状况、产量及水分利用效率的影响。结果表明:生物地膜覆盖条件下各指标与普通地膜覆盖差异性不显著(P>0.05),但出苗率平均较液态地膜和不覆膜处理高7.65%和8.24%,差异性达到显著或极显著水平。生物地膜覆盖玉米地上部干物质累积量、株高和叶面积指数均显著高于液态地膜和不覆膜处理(P<0.05),且在玉米生育前、中期差异性更为显著。生物地膜覆盖玉米产量平均较液态地膜和不覆膜处理高12.63%和14.69%,水分利用效率高13.55%和20.47%,差异性显著(P<0.05)。综合分析,河套灌区春玉米种植适宜采用生物地膜覆盖的方式。

关键词：地膜覆盖出苗率干物质累积株高叶面积指数水分利用效率

Ferric sulphate catalysed O-glucosylation using acetyl glucal in organic solvents

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Ferric sulphate catalysed O-glucosylation using acetyl gluca...

第七届全国磷化学化工暨第四届海峡化学生物学、生物技术与医药发展讨论会

作者： qingfeng Liu, Lei shi, Guisheng Zhang (College of Chemical and Environmental Science, Henan Normal University, Xinxiang, 453007)

Glycosidation of organic compounds have attracted considerable attention in current synthetic organic chemistry related to both biomolecules and functional *** acid catalyzed allylic rearrangement of glycals, known as the Ferrier rearrangement, is the method of choice for the synthesis of 2,.3-unsaturated *** have proven to be versatile intermediates in the synthesis of glycopeptide building blocks, uronic acids, modified

关键词： Lewis Ferric sulphate catalysed O-glucosylation using acetyl glucal in organic solvents

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汽轮机可倾瓦轴承低频振动诊断与处理

核动力工程 2016年第S1期37卷 38-42页

作者：王大成史庆峰王苗苗张精干中核核电运行管理有限公司浙江海盐314300

某600 MW核电汽轮机组在运行期间可倾瓦轴承上发生了非稳态振动。根据振动与负荷、润滑油量、转速等变量关系,从振动特征上判明可倾瓦轴承上出现的低频振动的主要原因是由于推力轴承油膜振荡和振动探头支架安装不佳导致的低频共振。提... 详细信息

某600 MW核电汽轮机组在运行期间可倾瓦轴承上发生了非稳态振动。根据振动与负荷、润滑油量、转速等变量关系,从振动特征上判明可倾瓦轴承上出现的低频振动的主要原因是由于推力轴承油膜振荡和振动探头支架安装不佳导致的低频共振。提出了改进处理建议,通过这些措施实施有效降低或消除轴承低频振动。

关键词：汽轮机可倾轴瓦低频幅值波动

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泥水盾构开挖面泥膜渗透特性与压力传递机制

岩土工程学报 2023年第9期45卷 1878-1887页

作者：徐涛史庆锋章定文徐敬民刘义怀东南大学交通学院江苏南京211189 南京东大岩土工程勘察设计研究院有限公司江苏南京210096

泥膜可以将泥浆压力传递到开挖面土体骨架上,转化为土体有效应力,因此泥膜的渗透特性是保持泥水盾构开挖面稳定的关键因素。采用泥浆渗透试验,研究了开挖面水力梯度、地层土体粒径和泥浆渣土含量等对泥膜形成的影响规律。试验结果显示,... 详细信息

泥膜可以将泥浆压力传递到开挖面土体骨架上,转化为土体有效应力,因此泥膜的渗透特性是保持泥水盾构开挖面稳定的关键因素。采用泥浆渗透试验,研究了开挖面水力梯度、地层土体粒径和泥浆渣土含量等对泥膜形成的影响规律。试验结果显示,水力梯度越小,越不利于泥膜形成。细砂地层有利于泥膜形成,但泥膜和渗透带很薄,易被破坏;中砂和粗砂地层虽不利于泥膜形成,较厚的渗透带却有利于开挖面稳定。泥膜的渗透系数比渗透带的渗透系数低100倍以上,渗透带的渗透系数介于10-7~10-5m/s,而泥膜的渗透系数的小于10-8m/s;泥膜或渗透带的渗透系数越小,地层超静孔压的影响范围越小,孔压下降得越快。当泥浆中掺有渣土时,泥浆的渗透速度高于未掺渣土的泥浆;渗透带的渗透系数随泥浆密度增大而增大,且地层超静孔压下降速率随泥浆密度增大而减小。

关键词：泥水盾构泥膜泥浆渗透带水力梯度土体粒径压力传递

A practical systematic strategy for preparation of uncommon sugars from rhamnal and glucal

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A practical systematic strategy for preparation of uncommon ...

第七届全国磷化学化工暨第四届海峡化学生物学、生物技术与医药发展讨论会

作者： Guisheng Zhang, Lei shi, qingfeng Liu (College of Chemistry and Environmental Science, Henan Normal University, Xinxiang, Henan 453007)

Uncommon sugars which are derived from common sugars (e.g. D-glucose) by replacement of at least one hydroxyl group or hydrogen atom with another functionnal group. They are often found in the structure of bioactive drugs. By analyzing varies glycosylated natural products and drugs, it was found that the majority of uncommon sugars are 2,6-deoxysugars. Due to their biologically importance in natural products, many efforts focused on the total synthesis of

关键词： A practical systematic strategy for preparation of uncommon sugars from rhamnal and glucal

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基于测量机器人的跨河高程测量应用研究

测绘与空间地理信息 2024年第4期47卷 180-182,185页

作者：施青峰杭州市勘测设计研究院有限公司浙江杭州310061

远距离跨河高程测量在水利基建工程项目中是被广为关注的问题,本文利用高精度测量机器人自动照准测量功能,采用四边形法精密三角高程测量方法进行远距离跨河高程测量作业,对其作业原理、测量步骤以及主要误差因素进行分析研究,并通过工... 详细信息

远距离跨河高程测量在水利基建工程项目中是被广为关注的问题,本文利用高精度测量机器人自动照准测量功能,采用四边形法精密三角高程测量方法进行远距离跨河高程测量作业,对其作业原理、测量步骤以及主要误差因素进行分析研究,并通过工程实例对该方法的高程控制测量成果精度进行综合分析,验证了四边形法精密三角高程测量能够满足二等水准测量精度要求,为远距离跨河高程测量提供了较为可靠的解决方案。

关键词：测量机器人四边形法三角高程测量高差闭合差

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道德与法治教学融入情感教育探究

成才之路 2022年第2期 133-135页

作者：施庆丰江苏省南通市海门区海南中学江苏南通226000

基于提升学生综合能力的教学目标,教师在道德与法治课程教学中,要改变传统的教学方式,积极融入情感教育内容。情感教育是一种新颖的教学模式,能够使学生与所学内容产生情感互动,从而形成正确的价值观。在具体教学中,教师要积极更新教育... 详细信息

基于提升学生综合能力的教学目标,教师在道德与法治课程教学中,要改变传统的教学方式,积极融入情感教育内容。情感教育是一种新颖的教学模式,能够使学生与所学内容产生情感互动,从而形成正确的价值观。在具体教学中,教师要积极更新教育理念,完善教学设计,应用案例教学法、小组探究法、故事教学法以及多媒体技术等,实现课堂组织的多样化,同时,增加社会实践内容,开展科学教学评价,以此不断提高情感教育应用于道德与法治课堂的教学效率,促进学生健康成长,全面发展。

关键词：道德与法治情感教育价值观案例教学法故事教学法

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