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有机化学萃取与洗涤实验基本操作规范建议 被引量:4
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作者 刘占祥 袁呈山 +12 位作者 韩杰 蔡双莲 张奇涵 吴琳 郑媛 孙兴文 刘庆文 熊英 余广鳌 杜欣 李厚金 张剑荣 张树永 《大学化学》 2025年第5期55-65,共11页
萃取、洗涤及干燥实验是有机化学实验的基本内容。熟练掌握并运用萃取和洗涤操作分离和纯化有机化合物是高校化学类专业学生必须掌握的基本实验技能。由于缺乏统一明确的操作规范,在实际的教学与实验过程中,可能造成实验结果的偏差、试... 萃取、洗涤及干燥实验是有机化学实验的基本内容。熟练掌握并运用萃取和洗涤操作分离和纯化有机化合物是高校化学类专业学生必须掌握的基本实验技能。由于缺乏统一明确的操作规范,在实际的教学与实验过程中,可能造成实验结果的偏差、试剂的浪费,甚至可能引发安全事故。本文针对有机化学中的萃取、洗涤及后续干燥实验提出了基本操作与规范建议,希望能为国内同行开展实验教学以及科研实践提供参考。 展开更多
关键词 有机化学实验 萃取 洗涤 干燥 操作规范
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有机化学回流实验基本操作规范建议 被引量:4
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作者 郑媛 李厚金 +12 位作者 刘占祥 吴琳 蔡双莲 熊英 余广鳌 孙兴文 刘庆文 韩杰 杜欣 袁呈山 张奇涵 张剑荣 张树永 《大学化学》 2025年第5期84-92,共9页
回流是有机化学实验的基本内容,大多数有机化学反应和操作(如重结晶)都是在回流条件下完成的。熟练掌握并运用回流操作是高校化学类专业学生必须掌握的基本实验技能。在有机化学实验中,如果回流操作不规范,可能导致实验产率低下,或者实... 回流是有机化学实验的基本内容,大多数有机化学反应和操作(如重结晶)都是在回流条件下完成的。熟练掌握并运用回流操作是高校化学类专业学生必须掌握的基本实验技能。在有机化学实验中,如果回流操作不规范,可能导致实验产率低下,或者实验失败,甚至还可能引发安全事故。本文对有机化学实验中的各种回流操作提出了基本操作规范建议,希望能为国内同行开展实验教学以及科研实践提供参考。 展开更多
关键词 有机化学实验 回流 操作规范
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有机化学升华实验基本操作规范建议 被引量:1
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作者 袁呈山 刘占祥 +12 位作者 杜欣 韩杰 郑媛 熊英 刘庆文 余广鳌 吴琳 蔡双莲 孙兴文 张奇涵 李厚金 张剑荣 张树永 《大学化学》 2025年第5期76-83,共8页
升华是一种重要的固体物质分离纯化技术,广泛应用于天然产物和合成化合物的精制。由于实验内容、实验条件以及所参考的教材对操作的描述存在差异,实验人员在进行升华实验时往往存在操作不规范的问题,导致产品纯度不合要求、产率降低,实... 升华是一种重要的固体物质分离纯化技术,广泛应用于天然产物和合成化合物的精制。由于实验内容、实验条件以及所参考的教材对操作的描述存在差异,实验人员在进行升华实验时往往存在操作不规范的问题,导致产品纯度不合要求、产率降低,实验结果偏差较大,甚至存在安全隐患。本文结合有机化学实验教学与科研实践经验,系统分析了常压升华和减压升华的适用范围和操作要点,提出了规范操作建议,以确保实验的安全性、高效性和可重复性,为同行提供参考。 展开更多
关键词 有机化学实验 升华 操作规范
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Development of an automatic measurement system using atmospheric pressure photoionization ultrahigh-resolution mass spectrometry and application for on-line analysis of particulate matter
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作者 Yayuan Dong Ranran Liu +4 位作者 ling Xie Xiaole Pan Yele Sun lin wu ZifaWang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第4期516-530,共15页
On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real tim... On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real time.Here we describe the development and application of an automatic measurement system that incorporates PM_(2.5)sampling,thermal desorption,atmospheric pressure photoionization,and UHRMS analysis.Molecular formulas of detected organic compounds were deducted from the accurate(±10 ppm)molecular weights obtained at a mass resolution of 100,000,allowing the identification of small organic compounds in PM_(2.5).Detection efficiencies of 28 standard compounds were determined and we found a high sensitivity and selectivity towards organic amines with limits of detection below 10 pg.As a proof of principle,PM_(2.5)samples collected off-line in winter in the urban area of Beijing were analyzed using the Ionization Module and HRMS of the system.The automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 hr.The detected organic compounds comprised mainly CHON and CHN compounds below 350 m/z.Pronounced seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in winter.This result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in summer.Diurnal variation in signal intensity of each formula provides crucial information to reveal its source and formation pathway.In summary,the automatic measurement system serves as an important tool for the on-line characterization and identification of organic species in PM_(2.5). 展开更多
关键词 PM_(2.5) Chemical composition On-line measurement technique High resolution mass spectrometry
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First-line immunotherapy for advanced non-small cell lung cancer:current progress and future prospects
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作者 Jingyi Wang lin wu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第2期117-124,共8页
Global Cancer Statistics 2022 reported the prevalence and high mortality rate of lung cancer.Notably,non-small cell lung cancer(NSCLC)accounts for the majority of the histologic types1.Precision therapy for lung cance... Global Cancer Statistics 2022 reported the prevalence and high mortality rate of lung cancer.Notably,non-small cell lung cancer(NSCLC)accounts for the majority of the histologic types1.Precision therapy for lung cancer has progressed rapidly and immune checkpoint inhibitors(ICIs)have become a leading research topic.Indeed,ICI therapy has been shown to improve the prognosis of lung cancer patients. 展开更多
关键词 LUNG CANCER MORTALITY
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有机化合物的物理常数测定基本操作规范建议
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作者 熊英 余广鳌 +12 位作者 吴琳 刘庆文 李厚金 蔡双莲 刘占祥 孙兴文 郑媛 韩杰 杜欣 袁呈山 张奇涵 张剑荣 张树永 《大学化学》 2025年第5期106-121,共16页
物理常数作为鉴定有机化合物及其纯度的重要依据,其准确测定也是有机化学实验教学的主要内容。本文主要介绍物理常数中熔点、沸点、折射率和比旋光度测定的作用、基本原理、常用方法、操作规范及实验注意事项等,并简要介绍了一些新的仪... 物理常数作为鉴定有机化合物及其纯度的重要依据,其准确测定也是有机化学实验教学的主要内容。本文主要介绍物理常数中熔点、沸点、折射率和比旋光度测定的作用、基本原理、常用方法、操作规范及实验注意事项等,并简要介绍了一些新的仪器测定方法,希望能为从事化学实验教学及科研的国内同行提供参考。 展开更多
关键词 有机化学实验 物理常数测定 操作规范
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有机化学色谱学实验基本操作规范建议 被引量:3
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作者 李厚金 吴琳 +12 位作者 孙兴文 郑媛 刘占祥 蔡双莲 熊英 余广鳌 刘庆文 韩杰 杜欣 袁呈山 张奇涵 张剑荣 张树永 《大学化学》 2025年第5期93-105,共13页
薄层色谱、柱色谱、纸色谱实验是有机化学实验的基本内容。熟练掌握并运用色谱技术分析、纯化、鉴定有机化合物是高校化学类专业学生必须掌握的基本实验技能。目前各高校色谱学实验的训练内容、要求和标准各不相同,达成的教学效果也存... 薄层色谱、柱色谱、纸色谱实验是有机化学实验的基本内容。熟练掌握并运用色谱技术分析、纯化、鉴定有机化合物是高校化学类专业学生必须掌握的基本实验技能。目前各高校色谱学实验的训练内容、要求和标准各不相同,达成的教学效果也存在较大差距。本文针对薄层色谱、柱色谱、纸色谱实验提出了基本操作与规范建议,希望能为国内同行开展实验教学以及科研实践提供参考。 展开更多
关键词 有机化学实验 薄层色谱 柱色谱 纸色谱 操作规范
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有机化学蒸馏实验基本操作规范建议 被引量:3
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作者 李厚金 蔡双莲 +12 位作者 郑媛 刘占祥 袁呈山 吴琳 余广鳌 韩杰 刘庆文 杜欣 熊英 张奇涵 孙兴文 张剑荣 张树永 《大学化学》 2025年第5期40-54,共15页
分析比较了常压普通蒸馏、空气冷凝的蒸馏、低沸点易燃易爆有机物的蒸馏、减压蒸馏、分馏、水蒸气蒸馏、旋转蒸发等蒸馏操作的共性及各自特点,明确不同实验操作的适用范围和条件,给出了各蒸馏实验的详细规范操作建议,同时指出了常见的... 分析比较了常压普通蒸馏、空气冷凝的蒸馏、低沸点易燃易爆有机物的蒸馏、减压蒸馏、分馏、水蒸气蒸馏、旋转蒸发等蒸馏操作的共性及各自特点,明确不同实验操作的适用范围和条件,给出了各蒸馏实验的详细规范操作建议,同时指出了常见的不规范或者错误操作。本蒸馏操作规范建议具有科学性、合理性,有助于提高实验效率和成功率,提升实验的本质安全,适用性强。 展开更多
关键词 有机化学实验 蒸馏 操作规范
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有机化学实验重结晶基本操作规范建议 被引量:2
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作者 钱雪伟 孙兴文 +13 位作者 李厚金 刘占祥 郑媛 吴琳 蔡双莲 熊英 余广鳌 刘庆文 韩杰 杜欣 袁呈山 张奇涵 张树永 张剑荣 《大学化学》 2025年第5期66-75,共10页
对有机化学实验中常用的重结晶基本操作进行了全面深入的剖析,涵盖重结晶原理、溶剂选择、基本操作步骤以及注意事项等方面。通过理论阐述以及实际案例中的情况分析,详细探讨了各因素对重结晶效果的影响,旨在为有机化学实验提供一套系... 对有机化学实验中常用的重结晶基本操作进行了全面深入的剖析,涵盖重结晶原理、溶剂选择、基本操作步骤以及注意事项等方面。通过理论阐述以及实际案例中的情况分析,详细探讨了各因素对重结晶效果的影响,旨在为有机化学实验提供一套系统、科学且实用的重结晶操作标准指南,实现有机化合物的高效、高质量纯化。 展开更多
关键词 有机化学实验 纯化 重结晶 操作规范
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Efficacy of Ulinastatin Combined with Continuous Renal Replacement Therapy in the Treatment of Sepsis Acute Kidney Injury and Its Effects on Systemic Inflammation, Immune Function and miRAN Expression
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作者 Yudong Guan lin wu Yang Xiao 《Open Journal of Nephrology》 CAS 2022年第3期323-331,共9页
Objective: To research the effectiveness of ulinastatin in combination with continuous renal replacement therapy in treating sepsis acute kidney injury and its effect on systemic inflammation, immune function and miRA... Objective: To research the effectiveness of ulinastatin in combination with continuous renal replacement therapy in treating sepsis acute kidney injury and its effect on systemic inflammation, immune function and miRAN expression. Methods: The 84 patients who were diagnosed with sepsis complicated by acute kidney injury in our hospital between May 2020 and June 2022 were chosen and randomly assigned to the study group (n = 42) and the control group (n = 42). Ulinastatin in combination with continuous renal replacement therapy was administered to the study group, whereas the control group was administered with continuous renal replacement therapy alone. Both groups’ clinical effects were observed. The levels of blood urea nitrogen (BUN), serum creatinine (SCr), tumor necrosis factor-α (TNF-α), high sensitivity Creactive protein (hs-CRP), vascular cell adhesion molecule-1 (VCAM-1), IgG, IgA, IgM, expression levels of miR-233 and miR-10a were compared among both the groups, pre-, and post-treatment. Results: The study group’s overall effectiveness rate was higher that is 95.24%, in comparison to the control group’s 78.57%, and this difference was statistically significant (P α, hs-CRP, VCAM-1, and miR-233 and miR-10a expression levels in both the study and control groups were decreased, however, the study group had reduced levels in comparison to the control group, with statistically significant differences (P P Conclusion: Ulinastatin in combination with continuous renal replacement therapy for treating sepsis acute kidney injury exhibits a positive effect and can significantly improve the systemic inflammation and immune function in patients. 展开更多
关键词 ULINASTATIN Immune Function Continuous Renal Replacement Therapy Systemic Inflammation Sepsis Acute Kidney Injury miRAN
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基于虚拟教研开展有机化学实验基本操作规范建设的探索与实践
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作者 李厚金 刘占祥 +12 位作者 郑媛 蔡双莲 韩杰 熊英 孙兴文 袁呈山 余广鳌 刘庆文 吴琳 张奇涵 杜欣 张剑荣 张树永 《大学化学》 2025年第5期230-237,共8页
分析了当前有机化学实验操作规范教学中存在的问题及其原因,指出了进行实验操作规范建设的重要性与制订原则,详细介绍了目前已开展的有机化学实验基本操作规范的建设内容、方法、编写要求以及已取得的建设成效。有助于同行更全面了解有... 分析了当前有机化学实验操作规范教学中存在的问题及其原因,指出了进行实验操作规范建设的重要性与制订原则,详细介绍了目前已开展的有机化学实验基本操作规范的建设内容、方法、编写要求以及已取得的建设成效。有助于同行更全面了解有机化学实验基本操作规范,在教学中指导学生熟练掌握规范、安全的实验操作技能,培养高素质化学专业人才。 展开更多
关键词 有机化学实验 操作规范 探索与实践
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Impact behavior and strain rate effects of artificial limestone by MICP 被引量:1
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作者 Yaru Lv lin wu +2 位作者 Zhigang Duan Yuchen Su Dongdong Zhang 《Biogeotechnics》 2025年第2期72-80,共9页
Natural cemented calcareous sand and limestone are highly complex and not well understood in terms of the me-chanical behavior due to the difficulty of obtaining undisturbed samples from far sea.This paper proposes an... Natural cemented calcareous sand and limestone are highly complex and not well understood in terms of the me-chanical behavior due to the difficulty of obtaining undisturbed samples from far sea.This paper proposes an artificial method in a laboratory setting using microbial-induced carbonate precipitation(MICP)to simulate the natural process of cementation of limestone.The artificially cemented sand has a high degree of similarity with the natural weakly limestone in three aspects:(1)the mineral composition of the cemented material is also granular calcite and acicular aragonite;(2)the microstructure in interconnected open pore network can be gradually closed and contracted with cementation.The porosity reaches to approximately 9.2%;(3)both the stress-strain relationship and the unconfined strength closely resemble that of natural weakly limestone.Furthermore,both static and dynamic behaviors of artificial limestone were studied by quasi-static compression tests and Split Hopkinson Pressure Bar(SHPB)tests,finding that the unconfined strength of weakly artifical limestone exponentially increases with increasing strain rate.A rate-dependent bond strength was proposed and implemented in software to reveal the mechanism of strain rate effects.It is found that the loading velocity is too high to keep in sync with the initiation and propagation of cracks under impact loading.This delay-induced viscosity may restrict the movement of the surrounding balls,thus increasing resistance. 展开更多
关键词 Weakly limestone MICP artificial cementation Calcareous sand Limestone impact behavior Strain rate effects
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福建省中稻—再生稻—油菜高效模式及配套栽培技术 被引量:1
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作者 林武 郑莉 张善辉 《中国种业》 2025年第6期188-190,共3页
中稻—再生稻—油菜种植模式与传统中稻—油菜模式相比增收一季稻谷,较传统中稻—再生稻增收一茬油料作物,对光温资源、肥料、农药等的利用率明显提升,经济效益、社会效益和生态效益明显,应用前景广阔。通过对再生稻、油菜品种选择,种... 中稻—再生稻—油菜种植模式与传统中稻—油菜模式相比增收一季稻谷,较传统中稻—再生稻增收一茬油料作物,对光温资源、肥料、农药等的利用率明显提升,经济效益、社会效益和生态效益明显,应用前景广阔。通过对再生稻、油菜品种选择,种植茬口安排,配套栽培技术等方面的研究,初步形成了福建省中稻—再生稻—油菜高效栽培模式与配套栽培技术。 展开更多
关键词 福建省 中稻—再生稻—油菜 高效模式 栽培技术
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深耕红色文化沃土推动新时代党史和文献工作高质量发展
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作者 林武 《中共党史研究》 北大核心 2025年第3期11-13,共3页
山东是人口大省、经济大省、文化大省,是中华文明的重要发祥地、儒家文化的发源地,素有“孔孟之乡、礼仪之邦”的美誉。习近平总书记对山东情深似海、厚望如山,党的十八大以来,先后6次到山东视察,去年5月再次亲临我省,赋予山东“走在前... 山东是人口大省、经济大省、文化大省,是中华文明的重要发祥地、儒家文化的发源地,素有“孔孟之乡、礼仪之邦”的美誉。习近平总书记对山东情深似海、厚望如山,党的十八大以来,先后6次到山东视察,去年5月再次亲临我省,赋予山东“走在前、挑大梁”的重大使命。我们牢记嘱托、感恩奋进,完整准确全面贯彻新发展理念,以进一步全面深化改革为动力,稳扎稳打、踏踏实实,加快建设绿色低碳高质量发展先行区,打造高水平对外开放新高地,现代化强省建设迈出坚实步伐。 展开更多
关键词 红色文化 党史 高质量发展 文献工作 新时代
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用于离子选择性电极的增塑剂/聚氯乙烯复合膜的表面润湿行为
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作者 吕桂芳 伍林 +5 位作者 石从云 李昊 陆自鹏 杜晨飞 周波 王小龙 《高分子材料科学与工程》 北大核心 2025年第2期126-133,共8页
以聚氯乙烯(PVC)为成膜基体材料,邻苯二甲酸二辛酯(DOP)、邻苯二甲酸二丁酯(DBP)、邻硝基苯辛基醚(o-NPOE)及癸二酸二辛酯(DOS)为增塑剂制备复合膜,增塑剂与PVC质量比范围为1.0~3.0,与前人制备离子选择电极膜中增塑剂/PVC质量比范围相... 以聚氯乙烯(PVC)为成膜基体材料,邻苯二甲酸二辛酯(DOP)、邻苯二甲酸二丁酯(DBP)、邻硝基苯辛基醚(o-NPOE)及癸二酸二辛酯(DOS)为增塑剂制备复合膜,增塑剂与PVC质量比范围为1.0~3.0,与前人制备离子选择电极膜中增塑剂/PVC质量比范围相近。通过接触角随时间变化研究了增塑剂用量和分子结构对膜表面结构和润湿性的影响。结果表明,复合膜表面接触角随时间的变化与体系中烷基链的偏转有关。质量比为1.5~3.0的DOP/PVC复合膜和质量比为1.0~3.0的DBP/PVC复合膜有陡降发生,且增塑剂含量越多,陡降发生得越早;不同质量比的o-NPOE/PVC和DOS/PVC复合膜中增塑剂分子很快发生了偏转,初始接触角与平衡接触角相差不大,60 s内减小2°左右。平衡接触角与增塑剂分子中非极性的脂肪碳原子数和极性基团个数的比值(A_(p)/P_(o))有关。增塑剂与PVC质量比为1.5~3.0时,DOP/PVC,o-NPOE/PVC和DOS/PVC体系A_(p)/P_(o)相等,平衡接触角基本接近,为88.0°;DBP/PVC体系A_(p)/P_(o)比前面三者小,平衡接触角小,仅有79.0°。 展开更多
关键词 增塑剂 聚氯乙烯复合膜 表面接触角 时间变化
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Expert consensus on the diagnosis and treatment of non-small cell lung cancer with MET alteration
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作者 Huijing Feng Yang Xia +106 位作者 Wenxian Wang Chunwei Xu Qian Wang Zhengbo Song Ziming Li Jinpu Yu Wenzhao Zhong Zhijie Wang Yongchang Zhang Jingjing Liu Shirong Zhang Xiuyu Cai Anwen Liu Wen Li Ping Zhan Hongbing Liu Tangfeng Lyu Liyun Miao lingfeng Min Gen lin Long Huang Jingping Yuan Zhansheng Jiang Xingxiang Pu Chuangzhou Rao DongqingLyu Zongyang Yu Xiaoyan Li Chuanhao Tang Chengzhi Zhou Qi Mei Hui Guo Qian Chu Rui Meng Xuewen Liu Jingxun wu Jin Zhou Zhengfei Zhu Weiwei Pan Fei Pang Meizhen Hu Kai Wang Fan wu Bingwei Xu ling Xu Liping Wang Youcai Zhu Jisheng Li Yanru Xie Xinqing lin Jing Cai lin Wang Yingying Du Wang Yao Xuefei Shi Xiaomin Niu Dongmei Yuan Yanwen Yao Jing Kang Jiatao Zhang Chao Zhang Wenbin Gao Jianhui Huang Yinbin Zhang Pingli Sun Hong Wang Mingxiang Ye Dong Wang Zhaofeng Wang Yue Hao Zheng Wang Bing Wan Donglai Lyu Xiaodong Jiao lin Shi Gang Lan Shengjie Yang Yanhong Shang Yina Wang Bihui Li Gang Jin Kang Zheng Jun Ma Wenfeng Li Zhang Zhang Zhongwu Li Yuan Li Zhefeng Liu Xuelei Ma Nong Yang lin wu Qiming Wang Guansong Wang Zhuan Hong Jiandong Wang Meiyu Fang Yong Fang Xixu Zhu Yi Shen Ke Wang Xiubao Ren Yiping Zhang Shenglin Ma Junping Zhang Yong Song Wenfeng Fang Yuanzhi Lu 《Cancer Biology & Medicine》 2025年第3期237-265,共29页
Alterations in the mesenchymal-epithelial transition factor(MET)gene are critical drivers of non-small cell lung cancer(NSCLC).In recent years advances in precision therapies targeting MET alterations have significant... Alterations in the mesenchymal-epithelial transition factor(MET)gene are critical drivers of non-small cell lung cancer(NSCLC).In recent years advances in precision therapies targeting MET alterations have significantly expanded treatment options for NSCLC patients.These alterations include MET exon 14 skipping mutations(MET exon 14 skipping),MET gene amplifications,MET point mutations(primarily kinase domain mutations),and MET protein overexpression.Accurate identification of these alterations and appropriate selection of patient populations and targeted therapies are essential for improving clinical outcomes.The East China Lung Cancer Group,Youth Committee(ECLUNG YOUNG,Yangtze River Delta Lung Cancer Cooperation Group)has synthesized insights from China’s innovative drug development landscape and clinical practice to formulate an expert consensus on the diagnosis and treatment of NSCLC patients with MET alterations.This consensus addresses key areas,such as optimal testing timing,testing methods,testing strategies,quality control measures,and treatment approaches.By offering standardized recommendations,this guidance aims to streamline diagnostic and therapeutic processes and enhance clinical decision-making for NSCLC with MET alterations. 展开更多
关键词 Mesenchymal-epithelial transition factor MET exon 14 skipping mutation MET amplification non-small cell lung cancer precision medicine targeted therapy tyrosine kinase
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Characterizations of air pollutants at roadside monitoring stations and traffic emission effects:A case study in Tianjin,China
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作者 Fangyuan Zheng Junxia Gao +8 位作者 lin wu Naixiu Sun Wentian Xu Qijun Zhang Hongjun Mao Jianfei Peng Liwei Li Ning Yang Bin Liu 《Journal of Environmental Sciences》 2025年第11期592-604,共13页
To investigate the response of Roadside Monitoring Stations(RSs)to traffic-related air pollution,traffic and pollutant characteristics,influencing factors,and potential source characterization in Tianjin,China were de... To investigate the response of Roadside Monitoring Stations(RSs)to traffic-related air pollution,traffic and pollutant characteristics,influencing factors,and potential source characterization in Tianjin,China were determined based on roadside monitoring of real-world data conducted at RSs in 2022.The diurnal variation trend of pollutants at RSs was consistent with that at the National Monitoring Station(NM),with notably higher pollutant fluctuations during the morning and evening peak traffic times at RSs,where the average diurnal concentration was 41.46%higher than that at the NM.The generalized additive model(GAM)for nitrogen oxides(NO_(x))and carbon monoxide(CO),responding to themultiple influencing factors,performed well at RSs,with deviance explained by 86.6%and 61.4%,respectively.The synergistic effects of wind direction and speed contributed to most of the variations in NO_(x) and CO,which were 14.74%and 12.87%,respectively.Pollutant concentrations were highest under windless conditions,with pollutants originating primarily from local vehicle emissions.The model results indicated that medium-duty truck(MDT)traffic flow predominantly contributed to the variability in NO_(x) emissions,whereas passenger car(PC)traffic flow was the primary source of CO emissions from traffic variables.MDTs should be the focus of urban NO_(x) traffic emissions control.Potential-source analysis validated the results obtained from the GAM,and both analyses showed that RSs can better characterize traffic-related air pollutants.Furthermore,more stringent emission standards have effectively mitigated the release of pollutants from motor vehicles and contributed to the modernization of vehicle fleet composition,effectively decreasing CO concentrations. 展开更多
关键词 Roadside monitoring station Traffic emissions Spatiotemporal variation Traffic-related air pollutants Generalized additive model(GAM)
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Carbon circular utilization and sequestration in depleted hydrocarbon reservoirs: Towards a carbon-neutral China
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作者 lin wu Zhengmeng Hou +5 位作者 Yang Li Weidong Wang Long Cheng Junzhang lin Zhifeng Luo Liangchao Huang 《Energy Geoscience》 2025年第1期101-112,共12页
The technology of carbon dioxide(CO_(2))enhanced hydrocarbon recovery is favored over other Carbon Capture,Utilization,and Sequestration(CCUS)methods for achieving the"double carbon"goal in China due to its ... The technology of carbon dioxide(CO_(2))enhanced hydrocarbon recovery is favored over other Carbon Capture,Utilization,and Sequestration(CCUS)methods for achieving the"double carbon"goal in China due to its ability to sequester CO_(2) geologically while enhancing the recovery rates of oil and gas resources.However,current technologies face significant challenges,such as limited recovery enhancement capacity,as well as high costs and low efficiency in carbon utilization and sequestration.To address these issues,an innovative carbon-negative technology termed Carbon Capture,Circular Utilization,and Sequestration(CCCUS)is proposed.This technology integrates CO_(2)-microbial enhanced hydrocarbon recovery,CO_(2) underground bio-methanation,and CO_(2) sequestration in depleted hydrocarbon reservoirs.Compared to conventional CCUS technologies,CCCUS stands out through both its modes of carbon utilization and the forms in which carbon exists,by cyclically biochemically converting endogenous and exogenous CO_(2) into renewable natural gas(RNG).A preliminary assessment indicates that CCCUS holds significant developmental potential in China,with 661 million tonnes of CO_(2) utilized per cycle and 3.47 billion tonnes ultimately sequestered.However,there is a significant lack of research on the core technology of CCCUS,specifically CO_(2) underground bio-methanation,in China.To bridge this gap and mitigate potential challenges during the development of CCCUS,targeted proposals have been formulated.This paper provides new insights into advancing the development of a circular carbon economy and accelerating the achievement of carbon neutrality in China. 展开更多
关键词 Carbon neutrality CCUS CCCUS Circular carbon economy Renewable natural gas(RNG)
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造林密度对黑木相思无性系人工林早期生长的影响
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作者 邓楠楠 林武 +4 位作者 林宝钦 陈宣霖 李夏 曾露阳 陈振生 《林业科技通讯》 2025年第7期109-111,共3页
为了解造林密度对黑木相思(Acacia melanoxylon)无性系人工林早期生长的调控机制,探索最佳造林密度,以组培苗SR-17为材料,在广西博白林场设置6种造林密度(1 000、1 100、1 250、1 333、1 560、1 667株/hm^(2)),连续监测1.7年生和2.4年... 为了解造林密度对黑木相思(Acacia melanoxylon)无性系人工林早期生长的调控机制,探索最佳造林密度,以组培苗SR-17为材料,在广西博白林场设置6种造林密度(1 000、1 100、1 250、1 333、1 560、1 667株/hm^(2)),连续监测1.7年生和2.4年生林分的树高、胸径及材积。结果表明:造林密度显著影响林木生长(P<0.05)。低密度(≤1 250株/hm^(2))通过减少资源竞争促进单株生长,1.7年生时1 560株/hm^(2)密度下胸径达8.11 cm,显著高于其他处理;2.4年生时1 250株/hm^(2)密度下树高(11.3 m)和单株材积(0.052 m^(3))最高。高密度(≥1 333株/hm^(2))通过株数补偿效应显著提升单位面积材积,2.4年生时1 333株/hm^(2)密度下材积累积量达67.42 m^(3)/hm^(2),较最低密度(1 000株/hm^(2))提升45.6%。研究表明,黑木相思人工林需根据经营目标选择密度:生态优先选择1 250株/hm^(2),经济优先选择1 333株/hm^(2)。 展开更多
关键词 黑木相思 Acaciamelanoxylon 造林密度 生长动态 资源竞争
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Investigating the Transport Mechanism of PM2.5 Pollution during January 2014 in Wuhan, Central China 被引量:15
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作者 Miaomiao LU Xiao TANG +9 位作者 Zifa WANG lin wu Xueshun CHEN Shengwen LIANG Hui ZHOU Huangjian wu Ke HU Longjiao SHEN Jia YU Jiang ZHU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第11期1217-1234,I0012-I0017,共19页
Severe haze pollution that occurred in January 2014 in Wuhan was investigated. The factors leading to Wuhan’s PM2.5 pollution and the characteristics and formation mechanism were found to be significantly different f... Severe haze pollution that occurred in January 2014 in Wuhan was investigated. The factors leading to Wuhan’s PM2.5 pollution and the characteristics and formation mechanism were found to be significantly different from other megacities, like Beijing. Both the growth rates and decline rates of PM2.5 concentrations in Wuhan were lower than those in Beijing, but the monthly PM2.5 value was approximately twice that in Beijing. Furthermore, the sharp increases of PM2.5 concentrations were often accompanied by strong winds. A high-precision modeling system with an online source-tagged method was established to explore the formation mechanism of five haze episodes. The long-range transport of the polluted air masses from the North China Plain (NCP) was the main factor leading to the sharp increases of PM2.5 concentrations in Wuhan, which contributed 53.4% of the monthly PM2.5 concentrations and 38.5% of polluted days. Furthermore, the change in meteorological conditions such as weakened winds and stable weather conditions led to the accumulation of air pollutants in Wuhan after the long-range transport. The contribution from Wuhan and surrounding cities to the PM2.5 concentrations was determined to be 67.4% during this period. Under the complex regional transport of pollutants from surrounding cities, the NCP, East China, and South China, the five episodes resulted in 30 haze days in Wuhan. The findings reveal important roles played by transregional and intercity transport in haze formation in Wuhan. 展开更多
关键词 HAZE POLLUTION regional transport WUHAN NORTH China PLAIN source-tagged method
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