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Journal of Environmental Sciences 2024年第2期136卷 615-625页

作者： Zhi-Ang Zhao Jingyun Mao chengjing Lu Shuangqiao Yang Qingrong Qian qinghua chen Hun Xue Xiaoli Sun Min-Quan Yang College of Environmental and Resource Sciences College of Carbon Neutral Modern IndustryFujian Key Laboratory of Pollution Control and Resource ReuseFujian Normal UniversityFuzhou 350007China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu 610065China

The design and synthesis of self-suspending photocatalyst device with easy recyclability is important for practical application.Here,this work utilizes aluminum-plastic package waste as raw material to prepare an aluminum-plastic supported TiO_(2)(AP-TiO_(2))photocatalyst device through 3D printing design and surface deposition method.A series of characterizations were carried out to explore the structure,morphology and performance of the AP-TiO_(2)device.Under UV light illumination,the AP-TiO_(2)-50 efficiently degrade 93.6%tetracycline hydrochloride(THC)after 4 hr,which increases by 8.3%compared with that of TiO_(2)powder suspension system with the same catalyst amount.Based on it,AP-ZnO,AP-CdS,AP-g-C_3N_4and AP-Pt-TiO_(2)are also fabricated,and applied in photocatalytic degradation and hydrogen evolution,which all exhibit higher photoactivities than powder suspension systems.This work provides a new avenue for the fabrication of advanced recyclable photocatalyst device.Moreover,the work offers a novel sight for the high-value utilization of aluminum-plastic package waste,which has positive implications for environmental protection.

关键词： TiO_(2) Self-suspending Photocatalyst device Aluminum plastic

Leucine regulates lipid metabolism in adipose tissue through adipokine-mTOR-SIRT1 signaling pathway and bile acid—microbe axis in a finishing pig model

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Animal Nutrition 2024年第1期16卷 158-173页

作者： Yunju Yin Saiming Gong Mengmeng Han Jingzun Wang Hanjing Shi Xianji Jiang Liu Guo Yehui Duan Qiuping Guo qinghua chen Fengna Li Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesHunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic ProcessHunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production College of Animal Science and Technology Hunan Agricultural University College of Modern Agricultural Sciences University of Chinese Academy of Sciences College of Life Science and Engineering Northwest Minzu University

This study was conducted to explore the regulatory mechanism of leucine (Leu) on lipid metabolism of finishing pigs.Twenty-four Duroc×Landrace×Large cross pigs with an average body weight of68.33±0.97 kg were randomly allocated into 3 treatment groups with 8 replicates per group (1 pig per replicate).The dietary treatments were as follows:control group (CON),0.25%Leu group and 0.50%Leu group.The experimental period was 42 d.The results showed as follows.(1) Compared with the CON,0.25%and 0.50%Leu increased (P<0.01) the average daily gain (ADG),while the average backfat thickness (ABT) and the ratio of feed intake to body weight gain (F:G ratio) were decreased (P<0.05).(2)In the 0.25%Leu group,the relative mRNA expression levels of sterol regulatory element binding protein-1c (SREBP1c),recombinant fatty acid transport protein 1 (FATP1),chemerin and peroxisome proliferatoractivated receptor γ (PPARγ) were decreased but the level of fatty acid binding protein 4 (FABP4) and fatty acid translocase (FAT/CD36) were increased in backfat tissue.In the 0.25%Leu group,the protein levels of p-Rictor,p-Raptor,p-eIF4E-binding protein 1 (p-4EBP1),p-silent mating type information regulator 2homolog 1 (p-SIRT1) and acetylation ribosome s6 protein kinase 1 (Ac—S6K1) were increased (P<0.05).(3) Compared to the CON,the diversity of gut microbiota in the 0.25%Leu group was increased.Principal component analysis showed that the relative abundance of Bacteroidetes,Lactobacillus and Desulfovibrio was higher in the 0.25%Leu group than the CON,but the relative abundance of Firmicutes,Treponema and Shigella was lower than in the CON (P<0.05).(4) Four different metabolites were screened out from the serum of finishing pigs including allolithocholic acid (alloLCA),isolithocholic acid (isoLCA),ursodeoxycholic acid (UDCA) and hyodeoxycholic acid (HDCA),which correlate to various degrees with the above microorganisms.In conclusion,Leu could promote adipose tissue lipolysis of finishing pigs through the mTOR-SIRT1 signaling pathway,and S6K1 is a

关键词： Leu Lipid metabolism Gut microbiota Bile acid

Fabrication of Silane and Desulfurization Ash Composite Modified Polyurethane and Its Interfacial Binding Mechanism

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 288-297页

作者：吴旺华 chen Shuichang YE Haodong 李世迁 LIN Yuanzhi 陈庆华 XIAO Liren College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117China College of Materials and Package Engineering Fujian Provincial Key Lab of Coastal Basin EnvironmentFujian Polytechnic Normal UniversityFuqing 350300China College of Agriculture Guangxi UniversityGuangxi 530004China

Polyurethane/desulfurization ash(PU/DA)composites were synthesized using"one-pot method",with the incorporation of a silane coupling agent(KH550)as a"molecular bridge"to facilitate the integration of DA as hard segments into the PU molecular chain.The effects of DA content(φ)on the mechanical properties,thermal stability,and hydrophobicity of PU,both before and after the addition of KH550,were thoroughly examined.The results of microscopic mechanism analysis confirmed that KH550 chemically modified the surface of DA,facilitating its incorporation into the polyurethane molecular chain,thereby significantly enhancing the compatibility and dispersion of DA within the PU matrix.When the mass fraction of modified DA(MDA)reached 12%,the mechanical properties,thermal stability,and hydrophobicity of the composites were substantially improved,with the tensile strength reaching 14.9 MPa,and the contact angle measuring 100.6°.

关键词： polyurethane silane coupling agent desulfurization ash modification mechanical property hydrophobicity thermal stability

Quantification of Methane Fluxes from Hydrocarbon Seeps to the Ocean and Atmosphere:Development of an in situ and Online Gas Flux Measuring System

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Journal of Ocean University of China 2017年第3期16卷 447-454页

作者： DI Pengfei chen qinghua chen Duofu CAS Key Laboratory of Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of Sciences Shanghai Engineering Research Center of Hadal Science and Technology College of Marine SciencesShanghai Ocean University

Natural hydrocarbon seeps in the marine environment are important contributors to greenhouse gases in the atmosphere. Such gases include methane, which plays a significant role in global carbon cycling and climate change. To accurately quantify the methane flux from hydrocarbon seeps on the seafloor, a specialized in situ and online gas flux measuring(GFM) device was designed to obtain high-resolution time course gas fluxes using the process of equal volume exchange. The device consists of a 1.0-m diameter, 0.9-m tall, inverted conical tent and a GFM instrument that contains a solenoid valve, level transducer, and gas collection chamber. Rising gas bubbles from seeps were measured by laboratory-calibrated GFM instruments attached to the top of the tent. According to the experimental data, the optimal anti-shake time interval was 5 s. The measurement range of the device was 0–15 L min^(-1), and the relative error was ± 1.0%. The device was initially deployed at an active seep site in the Lingtou Promontory seep field in South China Sea. The amount of gas released from a single gas vent was 30.5 m^3 during the measurement period, and the gas flow rate ranged from 22 to 72 Lh^(-1), depending on tidal period, and was strongly negatively correlated with water depth. The measurement results strongly suggest that oceanic tides and swells had a significant forcing effect on gas flux. Low flow rates were associated with high tides and vice versa. The changes in gas volume escaping from the seafloor seeps could be attributed to the hydrostatic pressure induced by water depth. Our findings suggest that in the marine environment, especially in the shallow shelf area, sea level variation may play an important role in controlling methane release into the ocean. Such releases probably also affect atmospheric methane levels.

关键词：烃渗出 GFM 设备在 situ 等于体积交换甲烷流动华南海

福州市骑行通勤环境PM_(2.5)中重金属污染特征及健康风险评估

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环境科学学报 2024年第6期44卷 300-307页

作者：胡海滨陈庆华福建理工大学建筑与城乡规划学院福州350118 福建师范大学资源与环境学院福建省污染控制与资源循环利用重点实验室福州350117

日益增大的城市骑行通勤群体面临着暴露于交通污染的风险,为研究福州市骑行通勤环境PM_(2.5)中重金属的暴露污染特征及健康风险,于2021年3—5月通勤高峰期间,在福州市典型道路上设置采样点,在骑行者呼吸高度上采集PM_(2.5)样品,对其所... 详细信息

日益增大的城市骑行通勤群体面临着暴露于交通污染的风险,为研究福州市骑行通勤环境PM_(2.5)中重金属的暴露污染特征及健康风险,于2021年3—5月通勤高峰期间,在福州市典型道路上设置采样点,在骑行者呼吸高度上采集PM_(2.5)样品,对其所含部分有毒痕量元素的浓度水平、污染程度和健康风险进行了分析.结果表明:所测9种元素中,Zn的浓度较高(246.0 ng·m^(-3)),其次为Cu、Pb、Cr、Mn、Ni(13.8~47.2 ng·m^(-3)),As、Cd、Co的浓度水平较低(1.0~2.3 ng·m^(-3));除Mn外,所有元素的骑行通勤环境浓度值均高于背景对照值并超过污染阈值,Cd、Cu和Zn属于严重污染水平,Pb、Ni为强-严重污染,Cr、As和Co为中等污染到强污染;健康风险评价结果显示,Mn对骑行通勤者存在潜在的非致癌风险;Cr和As具有一定的致癌风险.

关键词：福州骑行 PM_(2.5) 重金属健康风险

Retransmission Number Aware Channel Access Scheme for IEEE 802.11ax Based WLAN

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Chinese Journal of Electronics 2020年第2期29卷 351-360页

作者： ZHENG Yuan WANG Jiabin chen qinghua ZHU Yihua School of Computer Science and Technology Zhejiang University of Technology

The IEEE 802.11 ax amendment for the next generation of Wireless local area network(WLAN)provides the Orthogonal frequency division multiple access(OFDMA) mechanism. The Uplink OFDMAbased random access(UORA) supports multiple users to transmit uplink data simultaneously in different Resource units(RUs). With UORA, Access point(AP) uses trigger frame to dynamically announce eligible Random access RUs(RA-RUs) for the associated mobile stations(STAs),and a STA is allowed to select an RU to transmit when it picks an OFDMA-based random access backoff(OBO)counter no more than the number of the eligible RARUs. The UORA requires the STA with an unsuccessful transmission to double its OFDMA contention window(OCW) size for the followed retransmission, which causes the STA to endure a longer delay for retransmission(s).We propose the Retransmission number aware channel access(RNACA) scheme for IEEE 802.11 ax-based WLAN.In the RNACA, a failed STA makes decision on whether to double its OCW size or not by using a probability that considers the number of retransmissions, number of RUs,and number of STAs. Simulation results show that the proposed RNACA can gain a higher throughput and a lower packet delay.

关键词： IEEE 802.11ax WiFi WLAN OFDMA UORA

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中国式现代化德治建设的逻辑理路与实践路径

南京社会科学 2024年第4期 11-19页

作者：陈浦秋杭陈清华南京大学新闻传播学院南京210023 江苏省社会科学院哲学与文化研究所南京210004

中国式现代化语境下的德治建设具有深厚的传统文化渊源。但治理理念的创新和社会转型的张力使得传统德治遭遇现代挑战,这对新时代德治建设提出新要求。一方面,要求革新传统德治,依托法治、平等、自由的现代价值观,推动个体不仅要做一个... 详细信息

中国式现代化语境下的德治建设具有深厚的传统文化渊源。但治理理念的创新和社会转型的张力使得传统德治遭遇现代挑战,这对新时代德治建设提出新要求。一方面,要求革新传统德治,依托法治、平等、自由的现代价值观,推动个体不仅要做一个好公民,还要成为有新时代治理能力的主体;另一方面,要求社会不同主体在平等参与的前提下广泛深度互动,打造上下一体联动的居民自治共治的新型治理模式。此外,新时代德治在理论上同国家治理体系深度契合,推动其融入国家治理体系具有充分合理性和必要性。因此,深化新时代德治建设实践路径,在个体层面要以社区文化空间建构为抓手,推进新时代公民道德建设;在社区层面要以新时代精神文明建设为依托,促进党建引领与社区道德教育相结合;在社会层面要以城镇德育文明空间为载体,融合新时代德治建设与文化建设“三位一体”系统发展。

关键词：中国式现代化德治建设传统德治新时代德治国家治理体系

Application of modified amino acid as a chiral building block in asymmetric synthesis

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Chinese Science Bulletin 2001年第23期46卷 1952-1956页

作者： WANG Jianping ZHANG Xiyun chen qinghua Department of Chemistry Beijing Normal UniversityBeijing 100875China Department of Chemistry Luoyang Teacher’s CollegeLuoyang 471022China

Phenylglycine 1 as a representative of natural resourceful a-amino acid was modified by reduction and protection of functional group to afford the amino alcohol as a chiral building block 3. A new chiral compound, the chiral building block/spiro-cyclopropane derivative containing four stereogenic centers, compound 7, has been obtained in 52% yield with de≥98% via the tandem double Michael addition/internal nucleophilic substitution under mild condition of 5-l-menthyloxy-3-bromo-2-(5H)-furanone 4 with the nucleophilic reagent, the amino alcohol 3. The new chiral compound 7 is identified on the basis of its analytical data and spectroscopic data, such as UV, IR, 1H NMR, 13C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes 7 was established by X-ray crystallography. This result can provide new route and method for the introduction of chiral building block and the important synthetic strategy in synthesis of some complex molecules containing

关键词： modified α-amino acid phenylglycine amino alcohol chiral building block spiro-cyclopropane derivative stereochemistry and absolute configuration.

Numerical prediction of thermo-hydrodynamics on the gas-lubricated film in wedge-shaped microchannel

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排灌机械工程学报 2019年第8期37卷 692-698页

作者： ZHANG Xueqing ZHANG Yangang chen qinghua LIU Juanfang School of Energy and Power Engineering North University of ChinaTaiyuanShanxi 030051China Key Laboratory of Low-grade Energy Utilization Technologists and Systems of Ministry of Education College of Power EngineeringChongqing UniversityChongqing400030China

One wedge-shaped microchannel was established,and the hydrodynamic properties of the wedge-shaped gas film were comprehensively investigated.The Navier-Stokes equations coupled with the full energy equation were adopted to mainly analyze the lubrication hydrodynamics of the gas film,as the horizontal plate was viewed as the adiabatic wall or the horizontal plate temperature was equal to the tilt plate temperature.A higher gas film temperature strengthened the rarefaction effect,and the more rarefied gas weakened the squeeze.Meanwhile,the vertical flow across the gas film could indicate the relation between the velocity vector and the gas film squeeze and expansion.The adiabatic horizontal plate could resist the heat conduction and enhance the rarefaction effect,and thus the direction of motion of the gas molecules was easier to be changed.

关键词： thermo-hyrodynamics Navier-Stokes equations adiabatic horizontal plate wedge-shaped gas-lubricated film

ZnO-chitosan/Rectorite Nanocomposite Exhibiting High Photocatalytic Activities under Visible-light Irradiation

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 310-319页

作者： LI Shiqian Pen-Chi Chiang DING Ling Kinjal JShah chen qinghua chen Sheng College of Ocean and Bio-chemical Engineering Fujian provincial Key Lab of Coastal Basin EnvironmentFuqing Branch of Fujian Normal UniversityFuqing 350300China Graduate Institute of Environmental Engineering National Taiwan UniversityTaipei City 10673TaiwanChina College of Chemistry and Chemical Engineering Wuhan University of Science and TechnologyWuhan 430081China College of Urban Construction Nanjing Tech UniversityNanjing 211800China Engineering Research Center of Polymer Green Recycling Ministry of Education(Fujian Normal University)Fuzhou 350007China

Chitosan(CS),hydrated zinc acetate,and rectorite(REC) were used as raw materials to prepare CS-embedded zinc oxide(ZnO) nanoparticle by a chemical precipitation process.Hydrogen-bonded REC-loaded ZnO-CS nanoparticle was to form ZnO-CS/REC nanocomposite photocatalyst,its morphology and structure were analyzed by means of FTIR,XRD,TGA,SEM,and TEM.The effects of the catalyst dosage,methyl orange(MO) initial concentration and solution pH on photocatalytic performance were also discussed.The experimental results show that the ZnO-CS/REC nanocomposite has a particle size of 100 nm with good dispersion and uniformity.Under irradiation of visible light,0.6 g/L photocatalyst was used to degrade MO in solution for 90 min at pH 6,then the MO solution(10 mg/L) was decolored by more than 99%,indicating that the ZnO-CS/REC nanocomposite exhibited highly photocatalytic degradation activity.Therefore,the photodegradation kinetic mechanism of MO in aqueous solution is presumed.

关键词： ZnO-Chitosan/rectorite nanocomposite visible-light methyl orange photodegradation