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Vertical Distribution Characteristics of PM2.5 Observed by a Mobile Vehicle Lidar in Tianjin, China in 2016

Journal of Meteorological Research 2018年第1期32卷 60-68页

作者： Lihui LYU Yunsheng DONG Tianshu ZHANG Cheng liu wenqing liu Zhouqing XIE Yan XIANG Yi ZHANG Zhenyi CHEN Guangqiang FAN Leibo ZHANG Yang liu Yuchen SHI Xiaowen SHU Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 University of Science and Technology of China Hefei 230026 Tianjin Academy of Environmental Sciences Tianjin 300191 Chinese Academy of Sciences Wuxi Photonics Co. Ltd. Wuxi 214135 The AirForce Military Representative's Office in Beijing Beijing 100086

We present mobile vehicle lidar observations in Tianjin, China during the spring, summer, and winter of 2016. Mobile observations were carried out along the city border road of Tianjin to obtain the vertical distribution characteristics of PM2.5. Hygroscopic growth was not considered since relative humidity was less than 60% during the observation experiments. PM2.5 profile was obtained with the linear regression equation between the particle extinction coefficient and PM2.5 mass concentration. In spring, the vertical distribution of PM2.5 exhibited a hierarchical structure. In addition to a layer of particles that gathered near the ground, a portion of particles floated at 0.6–2.5-km height. In summer and winter, the fine particles basically gathered below 1 km near the ground. In spring and summer, the concentration of fine particles in the south was higher than that in the north because of the influence of south wind. In winter, the distribution of fine particles was opposite to that measured during spring and summer. High concentrations of PM2.5 were observed in the rural areas of North Tianjin with a maximum of 350 μg m^–3 on 13 December2016. It is shown that industrial and ship emissions in spring and summer and coal combustion in winter were the major sources of fine particles that polluted Tianjin. The results provide insights into the mechanisms of haze formation and the effects of meteorological conditions during haze–fog pollution episodes in the Tianjin area.

关键词： mobile vehicle lidar vertical concentration profile fine particle

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Review of Environmental Governance Research since the 18th CPC National Congress—Based on Bibliometric Analysis

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Contemporary Social Sciences 2021年第5期6卷 42-54页

作者： liu wenqing Zhou Wei School of Marxism Hainan University

Since the 18th CPC National Congress in 2012,the“ecological civilization”concept has been steadily *** has shown great resolution in green development and has achieved significant *** awareness of environmental governance has been deeply rooted in the hearts of the people;the reform continues to accelerate,and the ecological and environmental governance work has been *** paper takes CNKI(China National Knowledge Infrastructure)as the research database and analyzes published ecological and environmental governance documents since *** draws scientific conclusions and suggestions through data analysis,providing references for people to understand the current situation and hot spots of ecological and environmental governance research since the 18th CPC National Congress in 2012.

关键词： environmental protection the 18th CPC National Congress CiteSpace

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信息披露监管模式变更影响企业投资效率吗?——基于双重差分模型的实证检验

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财经理论与实践 2022年第4期43卷 67-77页

作者：林钟高刘文庆安徽工业大学商学院安徽马鞍山243002

基于制度变迁理论考察信息披露监管模式由“辖区监管”变更为“分行业监管”对投资效率的影响。研究发现:分行业信息披露监管模式的实施有效抑制了上市公司非效率投资行为,且对于低质量信息披露以及高盈余管理行为的上市公司抑制效应更... 详细信息

基于制度变迁理论考察信息披露监管模式由“辖区监管”变更为“分行业监管”对投资效率的影响。研究发现:分行业信息披露监管模式的实施有效抑制了上市公司非效率投资行为,且对于低质量信息披露以及高盈余管理行为的上市公司抑制效应更加明显;提高会计信息可比性,降低代理成本是其发挥抑制作用的重要路径。在排除了替代性解释和内生性问题以及通过安慰剂检验后,研究结论仍然成立。

关键词：信息披露监管模式分行业监管投资效率制度变迁

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Combustion Synthesis and Luminescent Properties of CaO: Eu^(3+), M^+ (M=Li, Na, K) Phosphor

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Journal of Wuhan University of Technology(Materials Science) 2010年第2期25卷 179-183页

作者：康明 College of Material Science and Engineering Southwest University of Science and Technology

Li ^＋ , Na^ ＋ , or K ^＋ co-doped CaO： Eu^3＋ phosphors were prepared by the combustion synthesis method and characterized by X-ray diffraction （XRD）, photoluminescence and photolumi-nescence excitation （PL-PLE） spectra. The experimental results show that, upon excitation with 250 nm xenon light, the emission spectrum of the CaO： Eu^3＋ consists of 4f-4f emission transitions from the 5D0 excited level to the 7FJ （J=1, 2, 3） levels with the mainly electric dipole transition 5D0→7F2 of Eu3＋, indicating that the Eu^3＋ occupies a low symmetry. The charge-transfer band （CTB） shows somewhat red shift with the decreasing ionic radii of co-doped alkali metal ions. The PL and PLE intensities are significantly enhanced, especially the strongest intensity of luminescent is CaO： Eu^3＋, Li ＋ phosphor, when alkali metal ions are incorporated. The strongest peak of emission is slightly shifted from 614 to 593 nm, indicating that the Eu^3＋ ion locates in a symmetric position （Oh） when alkali metal ions are incorporated.

关键词： luminescence CaO: Eu^3+ combustion method

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Cu对Fe-NiAlMn合金析出强化过程的影响

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材料工程 2022年第10期50卷 87-92页

作者：翟乾坤肖亚姣李嘉宝刘文庆上海大学材料科学与工程学院上海200444

将Fe-NiAlMn和Fe-CuNiAlMn合金在900℃固溶2 h后水淬,并在500℃时效不同时间。利用显微硬度测试和原子探针层析技术(APT)研究Cu的添加对Fe-NiAlMn合金析出强化过程的影响。结果表明:Cu的添加增强了时效初期的析出强化效果,加快了整个析... 详细信息

将Fe-NiAlMn和Fe-CuNiAlMn合金在900℃固溶2 h后水淬,并在500℃时效不同时间。利用显微硬度测试和原子探针层析技术(APT)研究Cu的添加对Fe-NiAlMn合金析出强化过程的影响。结果表明:Cu的添加增强了时效初期的析出强化效果,加快了整个析出强化进程。时效过程中,Cu元素首先偏聚形核成为富Cu相,并促使Ni,Al,Mn元素在富Cu相与基体界面处偏聚形核形成Ni(Al,Mn)相,两相为核壳结构。随着时效时间的延长,富Cu相由BCC结构转变为FCC结构,与Ni(Al,Mn)相逐渐分离。

关键词：富Cu相 Ni(Al,Mn)相析出强化原子探针层析技术

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肛门失禁的诊断及外科治疗研究进展

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医学综述 2024年第6期30卷 719-723页

作者：刘文庆刘世博邹博远唐茂盛苗成利北京大学国际医院腹膜后肿瘤肛肠外科北京102206

肛门失禁可严重影响患者身心健康、日常生活及社会交往,还可能合并严重并发症,增加家庭和社会负担。目前,肛门失禁的诊断主要依赖于病史、体格检查、生理检查及影像学检查等综合方案,这为该疾病的诊断提供了有价值的参考信息,并有利于... 详细信息

肛门失禁可严重影响患者身心健康、日常生活及社会交往,还可能合并严重并发症,增加家庭和社会负担。目前,肛门失禁的诊断主要依赖于病史、体格检查、生理检查及影像学检查等综合方案,这为该疾病的诊断提供了有价值的参考信息,并有利于后续治疗方案的制订。当前,肛门失禁的治疗以手术为主,如肛门括约肌修补手术、股薄肌成形术,在临床中应用广泛且疗效显著,但各术式也有不足之处。相信未来随着临床科学技术的不断发展,神经电刺激、人工括约肌植入术、股薄肌成形术等可获得更好的效果,并提高患者生活质量。

关键词：肛门失禁诊断外科治疗

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基于显著目标提取和泊松重建的红外与可见光图像融合方法

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激光与光电子学进展 2023年第16期60卷 175-184页

作者：刘文清王任华刘晓文杨馨中国人民公安大学信息网络安全学院北京100038

针对低照度环境下红外与可见光图像融合过程中存在显著目标不完整、边缘模糊和对比度不足等问题,提出一种基于显著目标提取和泊松重建的融合方法。针对红外图像像素之间强度显著性的差异,首先利用显著性检测、阈值分割和伽马校正的关联... 详细信息

针对低照度环境下红外与可见光图像融合过程中存在显著目标不完整、边缘模糊和对比度不足等问题,提出一种基于显著目标提取和泊松重建的融合方法。针对红外图像像素之间强度显著性的差异,首先利用显著性检测、阈值分割和伽马校正的关联性提取显著目标,从而实现红外图像中目标与背景的分离;其次考虑了源图像的视觉显著特征和梯度显著性,在梯度域上通过求解泊松方程重建融合图像;最后为提高低照度环境下融合图像的质量,利用红外图像的统计量均值和标准差优化融合结果。实验结果表明,所提方法在定性和定量分析方面均优于其他对比方法,能较好地突出红外目标信息,保留丰富的背景信息,视觉效果显著。

关键词：图像处理图像融合红外图像可见光图像泊松重建低照度

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Effectiveness and safety of combined nimotuzumab and S-1 chemotherapy with concurrent radiotherapy for locally advanced esophageal cancer in malnourished and elderly patients:A prospective phaseⅡstudy

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Chinese Journal of Cancer Research 2024年第3期36卷 270-281页

作者： Guojie Feng Jiao Li Nuo Yu Ziyu Zheng Xiongtao Yang Lei Deng Tao Zhang wenqing Wang Wenyang liu Jianyang Wang Qinfu Feng Jima Lyu Zefen Xiao Zongmei Zhou Nan Bi Jianjun Qin Xin Wang Department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100021China Department of Thoracic Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100021China

Objective:Definitive chemoradiotherapy(dCRT)is the standard treatment for unresectable locally advanced esophageal ***,this treatment is associated with substantial toxicity,and most malnourished or elderly patients are unable to complete this ***,there is a need for a more suitable radiotherapy combination regimen for this *** study was aimed to evaluate the efficacy and safety of a combination regimen comprising chemotherapy with nimotuzumab and S-1 and concurrent radiotherapy for patients with fragile locally advanced esophageal cancer with a high Nutritional Risk Screening 2002(NRS-2002)***:Eligible patients with unresectable esophageal carcinoma who had an NRS-2002 score of 2 or higher were *** were treated with S-1 and nimotuzumab with concurrent radiotherapy,followed by surgery or definitive *** primary endpoint was the locoregional control(LRC)***:A total of 55 patients who met the study criteria were *** completion of treatment,surgery was performed in 15 patients and radiotherapy was continued in 40 *** median follow-up period was 33.3[95%confidence interval(95%CI,31.4−35.1)]*** LRC rate was 77.2%(95%CI,66.6%−89.4%)at 1 year in the entire *** overall survival(OS)rate and event-free survival(EFS)rate were 57.5%and 51.5%at 3 years,*** was associated with better LRC[hazard ratio(HR)=0.16;95%CI,0.04−0.70;P=0.015],OS(HR=0.19;95%CI,0.04−0.80;P=0.024),and EFS(HR=0.25;95%CI,0.08−0.75;P=0.013).Most adverse events were of grade 1 or 2,and no severe adverse events ***:For malnourished or elderly patients with locally advanced esophageal cancer,radiotherapy combined with nimotuzumab and S-1 is effective and has a good safety profile.

关键词： Esophageal carcinoma squamous cell carcinoma nutritional risk score nimotuzumab S-1 definitive chemoradiotherapy

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Re effects in model Ni-based superalloys investigated with first-principles calculations and atom probe tomography

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Chinese Physics B 2020年第4期29卷 232-241页

作者：王殿武王崇愚于涛刘文庆 Central Iron and Steel Research Institute Beijing 100081China Department of Physics Tsinghua UniversityBeijing 100084China Key Laboratory for Microstructures Shanghai UniversityShanghai 200444China

The phase partition and site preference of Re atoms in a ternary Ni-Al-Re model alloy,including the electronic structure of different Re configurations,are investigated with first-principles calculations and atom probe *** Re distribution of single,nearest neighbor(NN),next-nearest neighbor(NNN),and cluster configurations are respectively designed in the models withγandγ*** results show that the Re atoms tend to enteringγphase and the Re atoms prefer to occupy the Al sites inγ*** Re cluster with a combination of NN and NNN Re-Re pair configuration is not preferred than the isolated Re atom in the Ni-based superalloys,and the configuration with isolated Re atom is more preferred in the ***,the electronic states are analyzed and the energetic parameters are *** electronic structure analyses show there exists strong Ni-Re electronic interaction and it is mainly contributed by the d-d *** characteristic features of the electronic states of the Re doping effects are also *** is also found that Re atoms prefer the Al sites inγside at the *** density of states at or near the Fermi level and the d-d hybridizations of NN Ni-Re are found to be important in the systems.

关键词： Re distribution first-principles calculations atom probe tomography Ni-based superalloys

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Prospect Analysis of the United States' Crude Oil Exports to the Asia-Pacific Region

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China Oil & Gas 2018年第2期25卷 41-48页

作者： Chen Bo Wang Pei liu wenqing China International United Petroleum & Chemicals Co. Ltd.

At the end of 2015, the United States lifted a 40-year ban on crude oil exports, which has far-reaching implications for the global crude oil market and crude oil trade patterns. Since the release of crude oil exports, with the recovery of crude oil production and improved export infrastructure in the United States, U.S. crude oil exports have been growing rapidly, with an average of about one million barrels/day in 2017, making the U.S one of the major global crude oil exporters. Currently, the AsiaPacific region has replaced North America as the first major destination for U.S. crude oil exports. In light of future trends in the oil refining industry of the Asia-Pacific region, it will usher in a new wave of refinery operations around 2020 and crude oil imports will continue to grow rapidly. The American region, represented by the United States, will replace West Africa as the second largest source of crude oil imports to the Asia-Pacific region, and that energy trade cooperation between the Asia-Pacific region and the United States will continue to grow. In particular, for China, the United States will become an important source of crude oil imports for our country in the future, and the two countries will shift from the past of energy competition to energy cooperation. Sino-US energy trade will play a more active role in economic and trade cooperation between the two countries.

关键词：原油出口美国勘探原油进口贸易合作原油贸易亚太区原油市场

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