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Frontiers of Environmental Science & Engineering 2010年第2期4卷 187-195页

作者： Qingyun CHANG Jingwen ZHANG Xin DU Jingjun MA jingci li Hebei Key Laboratory of Bioinorganic Chemistry College of ScienceAgricultural University of HebeiBaoding 071001China

A simple and efficient liquid-phase microextraction(LPME)technique was developed using ultrasound-assisted emulsification solidified floating organic drop microextraction(USAE-SFODME)combined with flame atomic absorption spectrometry,for the extraction and determination of trace copper in water samples.1-(2-Pyridylazo)-2-naphthol(PAN)was used as chelating *** efficiency factors(including extraction solvent type,extraction volume,time,temperature,and pH),the amount of the chelating agent,and salt effect were investigated and *** the optimum extraction conditions,figures of merit of the proposed method were *** calibration graph was linear in the range of 20–600 mg·L^(–1)with a detection limit of 0.76 mg·L^(–1).The relative standard deviation(R.S.D)for ten replicate measurements of 20 and 400 mg·L^(–1)of copper was 3.83%and 2.65%,***,the proposed method was applied to tap water,river water,and sea water,and accuracy was assessed through the analysis of certified reference water or recovery experiments.

关键词： ultrasound-assisted emulsification solidified floating organic drop microextraction flame atomic absorption spectrometry preconcentration copper

无溶剂、无催化剂条件下5-[(3-吲哚基)-芳甲基]-2,2-二甲基-1,3-二氧六环-4,6-二酮的合成

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有机化学 2003年第12期23卷 1416-1418页

作者：王春张英群李贵深李敬慈李晓陆河北农业大学理学院保定071001

在无溶剂和催化剂条件下 ,由芳香醛、吲哚、丙二酸亚异丙酯的三组分缩合反应 ,制备了 5 [( 3 吲哚基 ) 芳甲基 ] 2 ,2 二甲基 1,3 二氧六环 4,6 二酮 ,产率为 70 %～ 85 %,产物结构经1 HNMR 。

关键词： 5-[(3-吲哚基)-芳甲基]-2,2-二甲基-1,3-二氧六环-4,6-二酮缩合反应合成绿色化学固相有机反应

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无溶剂条件下5-亚烃基硫代巴比妥酸的合成

有机化学 2003年第8期23卷 858-860页

作者：李贵深王春李敬慈张英群李晓陆河北农业大学理学院保定071001

在无溶剂和催化剂条件下 ,采用室温研磨、加热和微波辐射的方法 ,由芳香醛和硫代巴比妥酸经Knoevenagel固相缩合反应高效率地制备了 5 亚烃基硫代巴比妥酸 ,产物结构经1HNMR ,13 CNMR和IR确证 .

关键词：无溶剂条件 5-亚烃基硫代巴比妥酸合成氮杂环化合物生物活性固相有机反应结构分析

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磷钨酸催化过氧化氢氧化环己烯合成己二酸

有机化学 2003年第1期23卷 104-105页

作者：张英群王春李贵深李敬慈河北农业大学理学院保定071001

报道了以苄基三乙基氯化铵为相转移催化剂 ,用磷钨酸催化过氧化氢氧化环己烯合成己二酸 ,在优化反应条件下 :即反应物摩尔比为环己烯∶H2 O2 ∶苄基三乙基氯化铵∶磷钨酸 =1∶4 5∶0 0 36∶0 0 0 15时 ,在 6 0～ 6 5℃反应 6h ,再将... 详细信息

报道了以苄基三乙基氯化铵为相转移催化剂 ,用磷钨酸催化过氧化氢氧化环己烯合成己二酸 ,在优化反应条件下 :即反应物摩尔比为环己烯∶H2 O2 ∶苄基三乙基氯化铵∶磷钨酸 =1∶4 5∶0 0 36∶0 0 0 15时 ,在 6 0～ 6 5℃反应 6h ,再将温度升至80℃反应 5h ,收率可达 87%.探讨了不同反应条件对产率的影响 .该方法避免了目前所常采用的对环境有污染的硝酸氧化方法所产生的氮氧化物及废酸 .

关键词：合成磷钨酸过氧化氢环己烯己二酸催化氧化苄基三乙基氯化铵催化剂

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芳香醛与硫代巴比妥酸固相缩合反应的研究

有机化学 2002年第11期22卷 905-908页

作者：李敬慈李贵深王春张英群李晓陆杨丽华河北农业大学理学院保定071001

研究了芳香醛与硫代巴比妥酸固态加热及室温下的缩合反应 ,两种反应条件得到同一产物——— 5 亚烃基硫代巴比妥酸 .由1 HNMR ,1 3CNMR ,IR ,UV等手段确定了产物的结构 .

关键词：芳香醛硫代巴比妥酸固相缩合反应 5—亚烃基硫代巴比妥酸

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铁路含油废水中油的形态和粒度分布

铁道劳动安全卫生与环保 1996年第1期23卷 8-10页

作者：陈泽昊李竞慈王玲铁科院金化所 100081

用重量法和紫外分光光度法研究了铁路内燃机务段、蒸汽机务段和车辆段含油废水中油的形态分布规律.废水中的油有15%～50%上浮至水面,40%～70%随悬浮物下沉,只有4%～30%的油滞留水中,此外使用显微镜计数法测定了油水乳状液中的油珠粒径,... 详细信息

用重量法和紫外分光光度法研究了铁路内燃机务段、蒸汽机务段和车辆段含油废水中油的形态分布规律.废水中的油有15%～50%上浮至水面,40%～70%随悬浮物下沉,只有4%～30%的油滞留水中,此外使用显微镜计数法测定了油水乳状液中的油珠粒径,废水中油珠粒径一般在30μm以下,并得出了油珠的粒度分布和质量分数.

关键词：含油废水形态分布粒度分布铁路

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He li li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei li Xiaoxiao Xu Xuan Wu Jiarui li Shiling Chen Danyang Chen Gaigai li Zhouping Tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke

Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 377-384页

作者： Yawei Xiao Qianqian Gu Haoyu li Mengyao li Yude Wang National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources School of Chemistry and Chemical Engineering Hainan University College of Chemical Engineering Fuzhou University Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies Yunnan University

Aqueous zinc-ion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion *** address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn2+diffusion *** employing electrodeposition to coat MoS2on the surface of BaV6O16·3H2O nanowires,the directional built-in electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn2+diffusion into the active *** optimized Zn2+diffusion coefficient in CC@BaV-6O16·3H2O@MoS2(7.5×10～8cm2s-1) surpasses that of most reported V-based ***,MoS2serving as a cathodic armor extends the cycling life of the Zn-CC@BaV6O16·3H2O@MoS2full batteries to over 10000 *** work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.

关键词： Internal electric field Cationic accelerator Ion diffusion kinetics Cathode modification strategy Aqueous zinc ion battery

Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： Lou Zhang Shuo li Fu Tang Jingkai Zhang Yuetong Kang Hean Zhang lidong li State Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing *** analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag *** prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial