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Science China Chemistry 2024年第6期67卷 1922-1928页

作者： Shasha zhang Wei Yao Anqi Lv Kun Liu yusheng zhang Chifeng Zhou Huili Ma Huifang Shi Zhongfu An Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech UniversityNanjing211816China

High-efficiency long-wavelength phosphorescence emissions of large singlet-triplet energy gap(ΔE_(ST))materials are essential for applications in biology and ***,few long-wavelength phosphorescence emissions of largeΔE_(ST)materials have been reported due to the weak spin-orbit coupling(SOC)and strong non-radiative ***,we develop a strategy to achieve highly efficient long-wavelength room temperature phosphorescence(RTP)emission of largeΔE_(ST)materials,which display bright red RTP emission with above 400μs lifetime and 6.5%phosphorescent quantum *** experiments and theoretical calculations reveal that the fishbone-like packing and the zig-zag interactions provide favorable conditions for suppressing the non-radiative transitions of triplet state excitons,and heavy atoms effectively promote the intersystem crossing(ISC)process for highly efficient long-wavelength phosphorescence *** universality of the method for highly efficient long-wavelength RTP emission of largeΔE_(ST)materials was further investigated in various ***,these materials with largeΔE_(ST)manifest the advantages of large color contrast on the display and utilization potentiality in information *** strategy paves the way for the high contrast display and development of information encryption with RTP emission.

关键词： room temperature phosphorescence singlet-triplet energy gap host-guest doping heavy atom effect red phosphorescence

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Transient breathing dynamics during extinction of dissipative solitons in mode‑locked fiber lasers

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Frontiers of Optoelectronics 2024年第1期17卷 9-19页

作者： Zichuan Yuan Si Luo Ke Dai Xiankun Yao Chenning Tao Qiang Ling yusheng zhang Zuguang Guan Daru Chen Yudong Cui Hangzhou Institute of Advanced Studies Zhejiang Normal UniversityHangzhou 311231China State Key Laboratory of Modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Optical Information Detection and Display Technology of Zhejiang Zhejiang Normal UniversityJinhua 321004China School of Physics Northwest UniversityXi’an 710127China

The utilization of the dispersive Fourier transformation approach has enabled comprehensive observation of the birth process of dissipative solitons in fiber ***,there is still a dearth of deep understanding regarding the extinction process of dissipative *** this study,we have utilized a combination of experimental and numerical techniques to thoroughly examine the breathing dynamics of dissipative solitons during the extinction process in an Er-doped mode-locked fiber *** results demonstrate that the transient breathing dynamics have a substantial impact on the extinction stage of both steady-state and breathing-state dissipative *** duration of transient breathing exhibits a high degree of sensitivity to variations in pump *** simulations are utilized to produce analogous breathing dynamics within the framework of a model that integrates equations characterizing the population inversion in a mode-locked *** results corroborate the role of Q-switching instability in the onset of breathing ***,these findings offer new possibilities for the advancement of various operational frameworks for ultrafast lasers.

关键词： Breathing soliton Fiber laser Dispersive Fourier transform Q-switched instability

An innovative classification system for ranking the biological effects of marine aromatic hydrocarbons based on fish embryotoxicity

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Acta Oceanologica Sinica 2024年第6期43卷 153-162页

作者： Ronghui Zheng Chao Fang Fukun Hong Min zhang Fulong Gao yusheng zhang Jun Bo Key Laboratory of Marine Ecological Conservation and Restoration Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China Observation and Research Station of Coastal Wetland Ecosystem in Beibu Gulf Ministry of Natural ResourcesBeihai 536015China

Petroleum hydrocarbon pollution is a global concern,particularly in coastal *** aromatic hydrocarbons(PAHs) are regarded as the most toxic components of petroleum *** this study,the biomonitoring and ranking effects of petroleum hydrocarbons and PAHs on the marine fish model Oryzias melastigma embryos were determined in the Jiulong River Estuary(JRE) and its adjacent waters in *** results showed that the levels of petroleum hydrocarbons from almost all sites met the primary standard for marine seawater quality,and the concentrations of the 16 priority PAHs in the surface seawater were lower compared with those in other coastal areas worldwide.A new fish expert system based on the embryotoxicity of ***(OME-FES) was developed and applied in the field to evaluate the biological effects of petroleum hydrocarbons and *** selected physiological index and molecular indicators in OME-FES were appropriate biomarkers for indicating the harmful effects of petroleum hydrocarbons and *** outcome of OME-FES revealed that the biological effect levels of the sampling sites ranged from level Ⅰ(no stress) to level Ⅲ(medium stress),which is further corroborated by the findings of nested analysis of variance(ANOVA) *** results suggest that the OME-FES is an effective tool for evaluating and ranking the biological effects of marine petroleum hydrocarbons and *** method may also be applied to evaluate other marine pollutants based on its framework.

关键词： petroleum hydrocarbons polycyclic aromatic hydrocarbons fish expert system integrated biomarker response nested one-way analysis of variance

Health risks and sources of trace elements and black carbon in PM_(2.5)from 2019 to 2021 in Beijing

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Journal of Environmental Sciences 2024年第8期142卷 69-82页

作者： Chenjie Hua Wei Ma Feixue Zheng yusheng zhang Jiali Xie Li Ma Boying Song Chao Yan Hongyan Li Zhen Liu Qian Liu Markku Kulmala Yongchun Liu Aerosol and Haze Laboratory Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Institute for Atmospheric and Earth System Research Faculty of ScienceUniversity of HelsinkiHelsinki 00014Finland School of Environment and Safety Taiyuan University of Science and TechnologyTaiyuan 030024China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

A comprehensive health risk assessment of PM_(2.5)is meaningful to understand the current status and directions regarding further improving air quality from the perspective of human *** this study,we evaluated the health risks of PM_(2.5)as well as highly toxic inorganic components,including heavy metals(HMs)and black carbon(BC)based on longterm observations in Beijing from 2019 to *** results showed that the relative risks of chronic obstructive pulmonary disease,lung cancer,acute lower respiratory tract infection,ischemic heart disease,and stroke decreased by 4.07%-9.30%in 2020 and 2.12%-6.70%in2021 compared with ***,they were still at high levels ranging from 1.26 to 1.77,in particular,stroke showed the highest value in *** had the highest hazard quotient(HQ,from 2.18 to 2.56)for adults from 2019 to 2021,while Ni,Cr,Pb,As,and BC showed high carcinogenic risks(CR>1.0×10^(-6))for *** HQ values of Mn and As and the CR values of Pb and As showed constant or slight upwards trends during our observations,which is in contrast to the downward trends of other HMs and PM_(2.5).Mn,Cr,and BC are crucial toxicants in PM_(2.5).A significant shrink of southern region sourcesof HMs and BCshrank suggests the increased importance of local ***,dust,and biomass burning are the major contributors to the non-carcinogenic risks,while traffic emissions and industry are the dominant contributors to the carcinogenic risks in Beijing.

关键词： PM_(2.5) Heavy metals Black carbon Health risk Source apportionment

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航天器复合材料产品关键工序质量控制研究

航天器工程 2024年第3期33卷 74-81页

作者：李莺歌张璇姚双张玉生中国空间技术研究院通信与导航卫星总体部北京100094 北京卫星制造厂有限公司北京100094

针对航天器复合材料产品系统复杂,研制技术难度大、成本高,以及多品种、小批量的生产模式导致可用于关键工序识别的样本数过少问题,从解决逐层分解法对关键工序识别和统计过程控制技术对工序质量控制的局限性出发,提出航天器复合材料产... 详细信息

针对航天器复合材料产品系统复杂,研制技术难度大、成本高,以及多品种、小批量的生产模式导致可用于关键工序识别的样本数过少问题,从解决逐层分解法对关键工序识别和统计过程控制技术对工序质量控制的局限性出发,提出航天器复合材料产品的关键工序识别思路,构建关键工序识别指标体系,规定指标量化数值的计算方法。采用因果图法,从人、机、料、法、环、测6个方面逐一梳理关键工序质量的影响因素,明确设计工艺性审查、工艺方案设计、工装设计、工艺规程设计、过程实施、过程检验、成品检验和检验信息反馈应用的质量控制措施。将上述措施应用于航天器复合材料载荷适配结构的研制,产品各项关键/重要特性均得到有效控制,实现以预防为主的质量控制与管理要求,研究结果可为航天器制造工序质量控制提供参考。

关键词：航天器复合材料产品关键工序质量控制影响因素

浅谈双碳背景下,包装如何更具功能性和便利性

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包装前沿 2024年第2期 8-9页

作者：章煜生广东丹青印务有限公司

本文主要介绍了包装更具功能性和便利性的几点措施。

关键词：包装几点措施便利性功能性

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高强耐压丁腈橡胶材料的制备与性能研究

安徽大学学报（自然科学版） 2024年第3期48卷 84-90页

作者：张雨生陈鹏左玉鑫杨斌安徽大学化学化工学院绿色高分子材料安徽省重点实验室安徽合肥230601 高性能橡胶材料及制品安徽省重点实验室安徽宁国242300

丁腈橡胶(NBR)在汽车零部件及密封圈领域应用广泛,为进一步提高丁腈橡胶的力学性能,笔者采用石墨烯纳米片(GNP)作为补强填料,制备环氧树脂(EP)包覆的添加剂GNP/EP,与白炭黑并用后制备得到环氧树脂包覆石墨烯/白炭黑/丁腈橡胶复合材料,... 详细信息

丁腈橡胶(NBR)在汽车零部件及密封圈领域应用广泛,为进一步提高丁腈橡胶的力学性能,笔者采用石墨烯纳米片(GNP)作为补强填料,制备环氧树脂(EP)包覆的添加剂GNP/EP,与白炭黑并用后制备得到环氧树脂包覆石墨烯/白炭黑/丁腈橡胶复合材料,以改善丁腈橡胶的拉伸和压缩形变性能.研究中,使用表面扫描电子显微镜(SEM)观察了复合填料和混炼胶的脆断截面形貌;使用橡胶加工分析仪(RPA)测试了复合材料的硫化时长、储能模量;使用万能试验机测试了橡胶材料的力学性能.研究结果表明:环氧包覆石墨烯/白炭黑复合填料在NBR中分散性提高,橡胶交联密度增大,力学性能提升.使用环氧包覆石墨烯与白炭黑并用增强NBR比使用原始石墨烯与白炭黑并用增强NBR可以取得更佳的断裂力学性能和耐压缩永久变形能力.

关键词：丁腈橡胶环氧树脂石墨烯纳米片白炭黑复合填料

基于体素形态学分析探讨脑梗死远隔丘脑和黑质损害研究

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中国神经精神疾病杂志 2024年第4期50卷 215-220页

作者：陈丹霞徐炳东皮凤玲张玉生梅州市人民医院神经内科暨南大学附属第一医院神经内科广州510630 暨南大学附属第一医院医学影像科广州510630

目的探讨颅脑核磁共振成像(magnetic resonance imaging,MRI)体素形态学分析(voxel-based mor⁃phometry,VBM)对检测脑梗死患者远隔丘脑和黑质继发性损害的临床价值。方法前瞻性招募19例首次单侧大脑中动脉(middle cerebral artery,MCA)... 详细信息

目的探讨颅脑核磁共振成像(magnetic resonance imaging,MRI)体素形态学分析(voxel-based mor⁃phometry,VBM)对检测脑梗死患者远隔丘脑和黑质继发性损害的临床价值。方法前瞻性招募19例首次单侧大脑中动脉(middle cerebral artery,MCA)供血区脑梗死患者,在发病后1周、1个月、3个月分别行MRI三维全脑扫描,应用VBM方法分析丘脑和黑质体积的变化。结果VBM结果显示,与发病1周时相比,脑梗死患者在发病1个月和3个月时同侧丘脑体积减小(体素值分别缩小637 mm^(3)、1488 mm^(3),P<0.01),且体积萎缩部位主要位于丘脑背内侧核。同样,与发病1周时相比,脑梗死患者在发病1个月和3个月时同侧黑质体积减小(体素值分别缩小64 mm^(3)、76 mm^(3),P<0.05)。结论VBM技术可在脑梗死后1~3个月检测MCA供血区脑梗死患者同侧丘脑和黑质体积缩小,可用于检测其继发性损害。

关键词：体素形态学分析大脑中动脉脑梗死丘脑黑质远隔损害磁共振成像

Fe-PG紫外光辅助活化H_(2)O_(2)流化床高效降解水杨酸

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环境工程学报 2024年第1期18卷 110-120页

作者：刘营营张玉生王全勇谢海涛张文郁中国城市建设研究院有限公司北京100120 山东华城工程技术有限公司济南250101 齐鲁工业大学化学与化工学院济南250353

针对常规光催化技术催化剂回收困难,紫外/双氧水(UV/H_(2)O_(2))技术残余H_(2)O_(2)污染严重等问题,采用浸渍法制备了铁负载多孔发泡玻璃(Fe-PG)并将其用于紫外光辅助活化H_(2)O_(2)流化床降解水杨酸(SA)。结果表明,在相同实验条件下,Fe... 详细信息

针对常规光催化技术催化剂回收困难,紫外/双氧水(UV/H_(2)O_(2))技术残余H_(2)O_(2)污染严重等问题,采用浸渍法制备了铁负载多孔发泡玻璃(Fe-PG)并将其用于紫外光辅助活化H_(2)O_(2)流化床降解水杨酸(SA)。结果表明,在相同实验条件下,Fe-PG紫外光辅助活化H_(2)O_(2)(UV/H_(2)O_(2)/Fe-PG)流化床工艺对SA的降解率、矿化率和H_(2)O_(2)利用率均明显优于UV/H_(2)O_(2)工艺;在考虑运行成本的情况下,最佳水力停留时间(HRT)为40 min,最佳H_(2)O_(2)投加量为3 mmol·L^(-1),最佳Fe-PG膨胀率为30%;UV/H_(2)O_(2)/Fe-PG流化床工艺对SA溶液初始质量浓度、pH和盐离子具有很强的耐受性,连续运行30 d后对SA的降解率仍维持在98%以上,矿化率仍高达78.1%。UV/H_(2)O_(2)/Fe-PG流化床工艺降解SA的主要活性物质为·OH、O_(2)^(·-)和h^(+),降解过程符合一级动力学。以上研究结果可为光催化辅助活化H_(2)O_(2)流化床技术实现工程应用提供技术支撑。

关键词： Fe-PG 光催化流化床水杨酸活性物质

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氮肥前移对水稻镉吸收转运的影响

分子植物育种 2024年第9期22卷 2996-3004页

作者：向焱赟张小毅尹林芝张玉盛肖欢敖和军湖南农业大学农学院长沙410128 湖南农业大学南方粮油协同创新中心长沙410128

为探究氮肥前移对水稻镉吸收特性及糙米镉含量的影响,以早稻品种‘株两优819’(低镉品种)、‘陆两优996’(高镉品种)和晚稻品种‘湘晚籼13号’(低镉品种)、‘玉针香’(高镉品种)为试验材料,设3组不同的蘖肥施用方法,F1:不施氮肥、F2:氮... 详细信息

为探究氮肥前移对水稻镉吸收特性及糙米镉含量的影响,以早稻品种‘株两优819’(低镉品种)、‘陆两优996’(高镉品种)和晚稻品种‘湘晚籼13号’(低镉品种)、‘玉针香’(高镉品种)为试验材料,设3组不同的蘖肥施用方法,F1:不施氮肥、F2:氮肥作为蘖肥一次性施入、F3:氮肥以基肥:蘖肥为6:4施入。试验结果表明:与F1相比,F2与F3显著降低了早晚稻季孕穗期至成熟期根部镉含量,抑制茎叶中镉的含量,其中以F3效果最佳;在成熟期F2、F3处理显著降低了各部位镉含量和各部位间转运系数,糙米镉含量以‘株两优819’、‘陆两优996’、‘湘晚籼13号’和‘玉针香’在F3时最低,较F1显著降低了62.50%、41.67%、48.00%和55.00%。水稻DCB-Cd依不同稻季表现不同,早稻为齐穗期>孕穗期,晚稻为孕穗期>齐穗期;早晚稻DCB-Fe表现为齐穗期>孕穗期;在氮肥前移处理下,氮素促进了早稻季根表铁膜形成,且糙米镉含量与根表铁膜间呈负相关性,在晚稻季则相反,故晚稻季镉含量会高于早稻季。因此,在水稻生产中,氮肥前移可达到降低糙米镉含量的目的。

关键词：水稻镉氮根表铁膜不同生育期