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Journal of Environmental Sciences 2024年第7期141卷 194-204页

作者： Tingting Xie liming cao Jinyi Zheng Peng Xuan Xiaofeng Huang Laboratory of Atmospheric Observation Supersite School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China

Effective density(ρ_(eff))is one of the most important physical properties of atmospheric particles,providing important references in exploring the emissions and aging processes of fresh *** this study,a combined system of differential mobility analyzer,centrifugal particle mass analyzer,and condensation particle counter was used to periodically measure theρ_(eff)of atmospheric particles in Shenzhen from Oct.2021 to *** showed that theρ_(eff)of particles with various size presented a bimodal distribution,which could be divided into main density(ρ_(m),main peak,corresponding to relatively dense particles after aging)and sub density(ρ_(s),sub peak,corresponding to fresh particles).The occurrence frequencies ofρ_(s)of particles with diameters of 50 and 80 nm were less than 20%,but were as high as about 40%of that with diameters from 120 to 350 ***ρ_(m)showed increasing trend with the size of particles,whileρ_(s)decreased as the increasing of the size of ***ρ_(eff)on pollution day varied significantly with chemical *** increasing of the proportion of sulfate could promote the increasing ofρ_(eff),while black carbon and organic matter caused opposite effects,which may be related to various factors,including the difference of the material density and morphology of various chemical ***ρ_(eff)of 50,80 and 120 nm particles decreased considerably during the new particle formation event,indicating that organic condensation was an important contributor to new particle growth.

关键词： DMA-CPMA-CPC Effective density Main/sub density Size distribution

Computational fluid dynamics simulation and experimental study on mixing performance of a three-dimensional circular cyclone-type microreactor

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Chinese Chemical Letters 2024年第4期35卷 382-388页

作者： Shiyu Hou Maolin Sun liming cao Chaoming Liang Jiaxin Yang Xinggui Zhou Jinxing Ye Ruihua Cheng School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China School of Pharmacy East China University of Science and TechnologyShanghai 200237China

Microchannels enable the fast and efficient mixing of multiphase *** this study, a millimeter-scale three-dimensional(3D) circular cyclone-type microreactor was designed for the *** flow characteristics and mixing intensity were simulated by computational fluid dynamics simulations at a flow rate range of 12–96 m L/min using a water/ethyl acetate *** the 3D variable-diameter structure,the microreactor induced paired opposite vortices and abruptly changed the local pressure to achieve a stable turbulent effect within the theoretical range of laminar *** injection simulations indicated that sufficient mixing units successfully promote fluid ***-coupling experiments showed a segregation index of X_S= 0.00,039 within a residence time of 9 *** experiments on the nbutanol/succinic acid/water system showed that the 3D circular cyclone-type microreactor achieved 100%extraction efficiency(E) in 4.25 s, and the overall volume mass transfer coefficient(K_La) reached 0.05–1.5s^(-1) in 12–96 m L/*** isolated yield of the phase transfer alkylation and oxidation reactions in the 3D circular cyclone-type microreactor achieved 99% within 36 s, which was superior to the coil microreactor and batch reactor.

关键词： Microfluidics Passive microreactor CFD simulation Extraction Liquid-liquid biphase reaction

A sequential continuous flow synthesis and purification process of calcium dibutyryladenosine cyclophosphate

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Chinese Chemical Letters 2024年第2期35卷 402-406页

作者： liming cao Maolin Sun Chaoming Liang Lei Yang Yueyue Ma Ruihua Cheng Yanxiong Ke Wei Yu Jinxing Ye Engineering Research Center of Pharmaceutical Process Chemistry Ministry of EducationSchool of PharmacyEast China University of Science and TechnologyShanghai 200237China School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China Shanghai No.1 Biochemical& Pharmaceutical Co. Ltd.Shanghai 200080China

Calcium dibutyryladenosine cyclophosphate is a widely used cardiovascular *** traditional batch synthesis process suffers from long reaction times,tedious operations,and unstable ***,a sequential continuous flow synthesis combined with a multistage in-line purification process of calcium dibutyryladenosine cyclophosphate was *** acylation reaction was completed in a continuous coil reactor at 160℃ in 20 *** the high toxic solvent pyridine was replaced by ***,the multistage in-line purification process was integrated into the homemade 3D circular cyclone-type micromixer *** with the membrane phase separators,the residence time of the purification step was 30 *** isolated yield of this sequential continuous process was 92%with 99%purity.

关键词： Flow chemistry Calcium dibutyryladenosine cyclophosphate Continuous flow synthesis In-line purification 3D circular cyclone-type micromixer chip

Two-step continuous flow process of sodium tanshinone ⅡA sulfonate using a 3D circular cyclone-type microreactor

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Chinese Chemical Letters 2024年第1期35卷 290-294页

作者： Maolin Sun Chaoming Liang liming cao Yaguo Wang Jiasheng Yang Shiyu Hou Wei Yu Yueyue Ma Ruihua Cheng Jinxing Ye School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China School of Pharmacy East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Shanghai No.1 Biochemical&Pharmaceutical Co. Ltd.Shanghai 200080China

A sustainable and practical process is presented for the direct synthesis of sodium tanshinone IIA sulfonate(STS).Our approach was inspired by the well-established and industrially applied batch synthetic route for STS *** constructed a telescoped two-step continuous flow *** involved a continuous tanshinone IIA sulfonation and in-line salt *** the setup,we constructed a 3D circular cyclone-type microreactor using femtosecond laser *** to the 68%yield for 2 h in batch,the two-step continuous flow had an STS yield of 90%,achieved for a total residence time of<3.0 min under optimal *** proposed continuous flow method vastly simplified the operation and improved procedural safety,while significantly reducing the required acid content and wastewater production.

关键词： Continuous flow Sodium tanshinone IIA sulfonate Cardiovascular Microreactor Green chemistry

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米勒循环汽油机燃烧噪声诊断与优化

应用声学 2024年第2期43卷 301-307页

作者：肖九长王毅曾小春曹黎明江铃汽车股份有限公司南昌330001 江西省汽车噪声与振动重点实验室南昌330001

对某搭载米勒循环增压汽油机的SUV在低速高负荷区域出现的“哒哒”异响进行诊断、分析及优化。噪声振动信号经傅里叶变换、滤波及燃烧压力频谱对比分析,确认异响为1~3.5 kHz的燃烧噪声。通过对米勒循环结构分析,确认异响产生根本原因为... 详细信息

对某搭载米勒循环增压汽油机的SUV在低速高负荷区域出现的“哒哒”异响进行诊断、分析及优化。噪声振动信号经傅里叶变换、滤波及燃烧压力频谱对比分析,确认异响为1~3.5 kHz的燃烧噪声。通过对米勒循环结构分析,确认异响产生根本原因为小升程进气凸轮进气时间短、阻力大和增压器低速性能不足,在低速中高负荷节气门全开下,采用了过大的点火提前角,导致气缸压力急剧升高诱发高压力升高率,带来燃烧噪声。通过对异响工况点火提前角优化,最高压力升高率及1~3.5 kHz燃烧压力频谱成分优化明显,异响消除,且发动机性能变化不大。

关键词：米勒循环燃烧噪声压力频谱点火提前角

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不同因素对公猪精液品质和母猪繁殖性能的影响

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畜牧与兽医 2024年第4期56卷 16-23页

作者：郑智伟曹立明郭伟闫之春德州市现代生猪养殖技术创新中心山东德州253000 山东新希望六和集团有限公司养猪研究院山东青岛266000

为了探究不同因素对公猪精液品质和母猪繁殖性能的影响,选取广西某种公猪站62头加系杜洛克公猪、74头长白公猪、221头大白公猪以及288头杜洛克母猪、247头长白母猪、1951头大白母猪为试验群体,通过混合线性模型与方差分析探究品种、采... 详细信息

为了探究不同因素对公猪精液品质和母猪繁殖性能的影响,选取广西某种公猪站62头加系杜洛克公猪、74头长白公猪、221头大白公猪以及288头杜洛克母猪、247头长白母猪、1951头大白母猪为试验群体,通过混合线性模型与方差分析探究品种、采精月份、采精月龄和采精间隔等因素对采精量、精液密度、精子活力、有效精子数的影响,并分析情期有效精子输入量、精子活力、配种季节、品种、母猪胎次对母猪受胎率、窝产总仔数的影响。结果:大白公猪采精量和有效精子数均高于长白公猪与杜洛克公猪(P0.05)。综上,品种、采精月份、采精月龄和采精间隔均会影响公猪精液质量,提高情期内有效精子输入量可提高杜洛克母猪受胎率和窝产总仔数,提升精子活力可提升杜洛克、大白和长白母猪受胎率与窝产总仔数。

关键词：公猪精液质量母猪分娩率产仔数

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现状、挑战和展望:中国卒中急救地图

中国卒中杂志 2024年第4期19卷 474-480页

作者：曹黎明廖雨琦池枫任力杰深圳大学第一附属医院神经内科深圳518025 深圳大学医学部深圳市第二人民医院神经内科

卒中是中国居民致死致残的主要原因,给社会带来了极重的负担。面对这一严峻的卒中救治形势,卒中急救地图应运而生。卒中急救地图通过地理信息系统和人工智能等先进技术整合医疗资源,构建了涵盖急救、转运、治疗到康复全流程的卒中救治网... 详细信息

卒中是中国居民致死致残的主要原因,给社会带来了极重的负担。面对这一严峻的卒中救治形势,卒中急救地图应运而生。卒中急救地图通过地理信息系统和人工智能等先进技术整合医疗资源,构建了涵盖急救、转运、治疗到康复全流程的卒中救治网络,可较为显著地提升卒中的急救效率并改善患者预后。作为创新技术平台,卒中急救地图在提升卒中急救效率和治疗效果方面至关重要。目前,中国卒中急救地图取得初步成效,且发展态势良好,然而在实际应用中,仍然面临一些重要挑战。为了更好地发挥地图的作用,未来的研究应着眼于如何完善这一平台,加强推广,提升应用效果,才能更好地应对我国严峻的卒中救治形势,减轻卒中为社会带来的沉重负担。

关键词：卒中急救地图地理信息系统现状挑战展望

不同方式联合TACE治疗原发性肝癌合并上消化道出血的临床疗效

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介入放射学杂志 2024年第1期33卷 33-37页

作者：曹莉明张勇学梁志会李亮崔进国任伟强联勤保障部队第九八〇(白求恩国际和平)医院介入治疗科河北石家庄050082 邯郸市中心医院血管介入二科

目的比较经颈内静脉肝内门体分流术(transjugular intrahepatic portal systemic shunt TIPS)、内镜治疗及药物治疗3种不同方式联合经肝动脉化疗栓塞术(transhepatic arterial chemoembolization TACE)对原发性肝癌合并门静脉高压、上消化道出血的临床疗效。方法纳入2014年1月至2020年6月联勤保障部队第九八〇医院原发性肝癌合并门静脉高压、上消化道出血患者105例,根据治疗方式分为TIPS联合TACE组25例,内镜联合TACE组30例,药物联合TACE组50例。比较3种不同治疗方式联合TACE治疗肝癌合并上消化道出血的临床疗效、出血复发率、肝性脑病发生率及生存率。结果3组患者治疗后6、12和24个月出血复发率差异有统计学意义(均P0.05)。TIPS组6个月和12个月肝性脑病发生率高于内镜组及药物组,差异有统计学意义(P0.05);3组患者24个月肝性脑病发生率差异无统计学意义(P>0.05)。TIPS组与内镜组6个月病死率差异无统计学意义(P>0.05),两组均低于药物组,且差异有统计学意义(P0.05)。结论TIPS联合TACE治疗原发性肝癌合并上消化道出血可降低上消化道出血复发率,有效控制肿瘤进展,延长生存期。

关键词：原发性肝癌内镜上消化道出血肝硬化经肝动脉化疗栓塞术经颈内静脉肝内门体分流术门静脉高压

Solid-state molecular dynamics of a torsion-variable ammonium embedded in a deformable supramolecular framework

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Chinese Journal of Structural Chemistry 2023年第2期42卷 23-28页

作者： Hui Xiao Liwen Ding Jingyan Liu Zhihui Jia liming cao Ziyi Du Chunting He College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China College of Chemistry Fuzhou UniversityFuzhou350108China

Accompanied by solid-state structural phase transitions,the switchable molecular dynamics(MD)and order-disorder transformation of(i-PrNHMe2)^(+)cation embedded in a deformable{[Ni(NCS)_(6)]^(4-)}_(∞)supramolecular framework are in-depth investigated by variable-temperature tests of single-crystal X-ray diffraction,dielectric measurement,and MD ***,it is found that the confined swinging or flipping of the(i-PrNHMe_(2))^(+)cation as a whole is assisted by a synergistic change of its torsion *** research provides a helpful insight into the solid-state MD of moderate-sized quasi-spherical molecules/ions that feature a flexible inner core.

关键词： Solid-state molecular dynamics Supramolecular framework Phase transition Dielectric

Flashover Characteristics of Dry Band-water band on Hydrophobic Surfaces

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 392-400页

作者： Xiaohan Wu Fanghui Yin Bin cao Daiming Yang Shichao Shao liming Wang Tsinghua-Berkeley Shenzhen Institute(TBSI) Shenzhen 518055China Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Shenzhen Polytechnic School Shenzhen 518055China

Due to their outstanding anti-flashover characteristics,composite insulators have been extensively applied in power systems.A lot of research has investigated flashover characteristics of hydrophobic specimens with artificial water ***,the phenomenon is not consistent with that of the contaminated composite *** the test specimens covered with water droplets,there is no obvious leakage current before the flashover and no obvious relationship between flashover voltage and the conductivity of water *** the contaminated composite insulator surface,there are short continuous arcs on the insulators before critical flashover,making insulators look like a luminous *** that under these two conditions,the proportion of water along the insulation distance is different,the flashover characteristic of“dry band-water band”on a hydrophobicity surface is analyzed in the present *** influence of the water band parameter(including length,width,and conductivity)as well as the length of dry band is *** this basis,the arc generation and development process of the surface covered with“dry band-water band”is *** research results improve the understanding of the flashover process on contaminated composite insulators.

关键词： Flashover characteristics hydrophobicity partial arc water band