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曼氏无针乌贼(Sepiella japonica)在不同盐度胁迫下的生理生化和组织学响应特征分析

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海洋与湖沼 2024年第4期55卷 951-959页

作者：郝晴崔闻博谷敏李双周旭迟长凤浙江海洋大学海洋科学与技术学院、海洋生物种质资源发掘利用国家地方联合工程研究中心浙江舟山316022

盐度是影响海洋生物代谢和渗透调节最重要的生态因子之一,它的变化会影响头足类动物的能量收支、胚胎发育、个体生长、免疫能力、繁殖能力等多个方面,还会直接影响血清渗透压、离子浓度、抗氧化能力和游离氨基酸含量。为探究盐度胁迫对... 详细信息

盐度是影响海洋生物代谢和渗透调节最重要的生态因子之一,它的变化会影响头足类动物的能量收支、胚胎发育、个体生长、免疫能力、繁殖能力等多个方面,还会直接影响血清渗透压、离子浓度、抗氧化能力和游离氨基酸含量。为探究盐度胁迫对成体曼氏无针乌贼(Sepiella japonica)生理生化和组织学的影响,分别利用高盐(32)和低盐(18)对乌贼进行胁迫处理。结果显示,低盐胁迫6、12和24 h后,乌贼血淋巴中的Na^(+)、Cl^(-)、K^(+)、Ca^(2+)浓度相较于正常盐度组均显著性下降。高盐胁迫12和24 h后,血淋巴中的Na+浓度相较于正常盐度组显著性上升;Ca^(2+)浓度在12 h后显著性上升。肝脏中SOD活力和CAT的表达量在盐度胁迫6 h后显著下降。鳃中Na^(+)/K^(+)-ATP酶α亚基和Ca^(2+)-ATP酶的表达量在低盐胁迫24 h后显著下降。此外,H.E染色显示,低盐胁迫会造成乌贼鳃和肾组织核质比降低以及肝脏的病理性损伤,而在高盐胁迫后无变化。研究结果从生理生化水平和组织学水平解析曼氏无针乌贼成体在不同盐度胁迫下的响应特征,为曼氏无针乌贼和头足类的盐度响应研究提供了形态学支撑和理论依据,也对乌贼养殖过程中应对盐度波动具有一定的参考价值。

关键词：曼氏无针乌贼盐度胁迫生理生化特征酶活性组织学分析

Synthesis and Properties of Reversible Disulfide Bond-based Self-healing Polyurethane with Triple Shape Memory Properties

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Chinese Journal of Polymer Science 2019年第11期37卷 1119-1129页

作者： Han Jia Kun chang Shu-Ying gu Department of Polymeric Materials School of Materials Science and Engineering Tongji University Shanghai 201804 China Key Laboratory of Advanced Civil Engineering Materials Ministry of Education Tongji University Shanghai 201804 China

A reversible disulfide bond-based self-healing polyurethane with triple shape memory properties was prepared by chain extending of random copolymer poly(lactide-co-caprolactone)(PCLA), hexamethylene diisocyanate (HDI), polytetrahydrofuran (PTMEG), and 4,4,-aminophenyl disulfide. The chemical structures were characterized using 1H nuclear magnetic resonance (^1H-NMR) spectroscopy, Fourier transform infrared spectroscopy (FTIR), and gel permeation chromatography (GPC). The thermal properties, selfhealing properties, triple-shape memory effect, and quantitative shape memory response were evaluated by differential scanning calorimetry (DSC), tensile tests, two-step programming process thermal mechanical experiments, and subsequent progressive thermal recovery. The self-healing mechanism and procedures were investigated using polarizing optical microscopy (POM) and an optical profiler. It was concluded that self-healing properties (up to 60%) and triple-shape memory properties around 35 and 50℃(with shape fixation ratios of 94.3% and 98.3%, shape recovery ratios of 76.6% and 85.1%, respectively) were integrated to the shape memory polyurethane. As-prepared polyurethane is expected to have potential applications in multi-shape coatings, films, and step-by-step deploying structures.

关键词： Self-healing Reversible disulfide bond Triple shape memory Polyurethane

Mastering lanthanide energy states for next-gen photonic innovation

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中国科学:化学英文版 2023年第9期66卷 2460-2479页

作者： Yuyang gu chang gu Yuxiang Zhang Zhen Mu Xiaogang Liu Department of Chemistry National University of SingaporeSingapore 117543Singapore Institute of Materials Research and Engineering Agency for ScienceTechnology and ResearchSingapore 138634Singapore

Lanthanide-based photonic materials have been extensively explored for use in laser crystals,lighting,fiber-optic communications,bioimaging,diagnostics,and many other *** recent years,they have enabled numerous breakthroughs in areas such as single-particle spectroscopy,super-resolution imaging,micro-lasing,lifetime multiplexing,and ***,we summarize recent advances in lanthanide photonic materials from an energy state perspective,focusing on the interplay between energy state manipulation and advanced photonic *** then discuss the challenges and prospects for controlling energy states at the single-particle *** wish to highlight the importance of quantifying and understanding the energy states of lanthanides for future innovations.

关键词： lanthanide nanomaterials super-resolution lifetime lasing

10B-doped MCP detector developed for neutron resonance imaging at Back-n white neutron source

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Nuclear Science and Techniques 2024年第8期35卷 58-68页

作者： Qiang Li Li‑Jiao Wang Jing‑Yu Tang Xiang‑Biao Qiu Zhen Chen Mao‑Yuan Zhao chang‑Jun Ning Kai Pan Wei Xu Tao Li Su‑Peng Lu Han Yi Rui‑Rui Fan chang‑Qing Feng Rong Zhang Xiao‑Yang Sun Qi An Hao‑Fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Yong‑Hao Chen Zeng‑Qi Cui An‑Chuan Fan Fan‑Zhen Feng Min‑Hao gu chang‑Cai Han Zi‑Jie Han guo‑Zhu He Yong‑Cheng He Yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang Bo Li Gong Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Yi‑Na Liu guang‑Yuan Luan Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song Kang Sun Zhi‑Xin Tan Sheng‑Da Tang Jin‑Cheng Wang Peng‑Cheng Wang Zhao‑Hui Wang Zhong‑Wei Wen Xiao‑guang Wu Xuan Wu Cong Xia Yong‑Ji Yu guo‑Hui Zhang Hang‑chang Zhang Lin‑Hao Zhang Qi‑Wei Zhang Xian‑Peng Zhang Yu‑Liang Zhang Yue Zhang Zhi‑Yong Zhang Zhi‑Hao Zhou Ke‑Jun Zhu Chong Zou Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China North Night Vision Science and Technology(Nanjing)Research Institute Co.Ltd Nanjing 211106China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Modern Physics Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China China Academy of Engineering Physics Institute of Nuclear Physics and ChemistryMianyang 621900China USTC archaeometry lab University of Science and Technology of ChinaHefei 230026China Northwest Institute of Nuclear Technology Xi’an 710024China University of Chinese Academy of Sciences Beijing 100049China China Shipbuilding Trading Co. LtdBeijing 100044China

Neutron resonance imaging(NRI)has recently emerged as an appealing technique for neutron *** complexity surpasses that of conventional transmission imaging,as it requires a high demand for both a neutron source and ***,the progression of NRI technology has been sluggish since its inception in the 1980s,particularly considering the limited studies analyzing the neutron energy range above *** white neutron source(Back-n)at the China Spallation Neutron Source(CSNS)provides favorable beam conditions for the development of the NRI technique over a wide neutron energy range from eV to ***-sensitive microchannel plates(MCP)have emerged as a cutting-edge tool in the field of neutron detection owing to their high temporal and spatial resolutions,high detection efficiency,and low *** this study,we report the development of a 10B-doped MCP detector,along with its associated electronics,data processing system,and NRI experiments at the *** heavy elements such as gold,silver,tungsten,and indium can be easily identified in the transmission images by their characteristic resonance peaks in the 1–100 eV energy range;the more difficult medium-weight elements such as iron,copper,and aluminum with resonance peaks in the 1–100 keV energy range can also be *** particular,results in the neutron energy range of dozens of keV(Aluminum)are reported here for the first time.

关键词： Neutron resonance imaging 10B doped MCP detector White neutron source Sample nuclide identification

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水利工程混凝土冬季施工浇筑及养护技术研究

东北水利水电 2024年第1期42卷 11-13,40,71页

作者：顾介昌钟琦连云港市赣榆区班庄镇水利管理服务站江苏赣榆222100 连云港市赣榆区厉庄镇水利管理服务站江苏赣榆222100

本文针对冬季施工混凝土浇筑出现实际高程与设计高程不一致,延长工程施工工期的问题,设计了水利工程混凝土冬季施工浇筑及养护技术。通过安装劲性骨架,悬臂浇筑混凝土,围绕劲性骨架进行浇筑施工,快速成型,避免混凝土浇筑出现冰冻现象。... 详细信息

本文针对冬季施工混凝土浇筑出现实际高程与设计高程不一致,延长工程施工工期的问题,设计了水利工程混凝土冬季施工浇筑及养护技术。通过安装劲性骨架,悬臂浇筑混凝土,围绕劲性骨架进行浇筑施工,快速成型,避免混凝土浇筑出现冰冻现象。应用冬季相变养护材料及蓄热储能材料,及时对浇筑完成的混凝土进行控温补偿,从而保证冬季混凝土浇筑施工的有效性。通过实例验证,可为其他类似工程提供借鉴。

关键词：水利工程混凝土冬季施工浇筑养护技术劲性骨架

Impacts of the COVID-19 pandemic on vegetable production and countermeasures from an agricultural insurance perspective

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Journal of Integrative Agriculture 2020年第12期19卷 2866-2876页

作者： gu Hai-ying WANG chang-wei Antai College of Economics and Management Shanghai Jiao Tong UniversityShanghai 200030P.R.China Institute of Industry Research Shanghai Jiao Tong UniversityShanghai 200030P.R.China Institute of Finance and Economics Shanghai University of Finance and EconomicsShanghai 200433P.R.China

In the face of the corona virus disease 2019(COVID-19)pandemic,it is essential to stabilize the security of urban“shopping baskets”.Through a survey and interviews with 46 agricultural cooperatives in Shanghai,this paper analyzes the impact of the pandemic on vegetable production and offers suggestions on agricultural *** research results show that:(1)the pandemic has impacted almost all stages of the vegetable supply chain but has had a greater impact on the sales stage;(2)the market risks of vegetable production have increased significantly,and the gap between the field price and the market price has *** sales price difference between traditional channels and e-commerce is notable;(3)farmers’incomes have generally declined due to the COVID-19 pandemic,and traditional small-scale farmers have suffered more losses;and(4)agricultural insurance plays an important role in stabilizing the supply of vegetables to the *** minimize the impact of the pandemic on vegetable production and to stabilize both urban“shopping baskets”and farmers’incomes,it is necessary to further improve agricultural insurance,especially to provide insurance against market risks.

关键词： COVID-19 vegetable supply chain agricultural insurance market risks

夜晚蓝光和白光暴露对肝脏生物钟节律和肝脏炎症反应影响的差异

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光谱学与光谱分析 2024年第10期44卷 2865-2872页

作者：梁昕悦曾晶艾常鹏罗杰承范晓静吴胜男顾瑛解放军医学院北京100853 解放军总医院第一医学中心激光医学科北京100853 北京理工大学医学技术学院北京100081 解放军总医院第五医学中心内分泌科北京100071

光对昼夜节律的调控属于非成像视觉功能,以自主感光视神经节细胞为主的非成像视觉效应细胞对机体的生物节律、代谢和认知等有显著影响,主要由蓝光介导。该研究探索夜晚蓝光和白光暴露对肝脏生物钟节律以及肝脏炎症反应的影响。将沙鼠每... 详细信息

光对昼夜节律的调控属于非成像视觉功能,以自主感光视神经节细胞为主的非成像视觉效应细胞对机体的生物节律、代谢和认知等有显著影响,主要由蓝光介导。该研究探索夜晚蓝光和白光暴露对肝脏生物钟节律以及肝脏炎症反应的影响。将沙鼠每晚暴露在蓝光或白光中1或3 h,持续10周,采用实时荧光定量PCR检测肝脏生物钟基因表达节律,采用转录组学分析肝脏全部基因表达水平,采用H&E染色和免疫荧光法观察肝脏组织形态及炎症因子水平。研究结果显示,夜晚光照对肝脏多种生物钟基因Arntl、Clock、Cry1、Nr1d1、Per2和Ror-α表达节律均造成显著破坏。夜晚光照对肝脏免疫系统基因表达的影响最显著。夜晚光照可引起肝细胞水肿,上调促炎因子白介素17A和粒细胞-巨噬细胞集落刺激因子的表达。夜晚光照暴露扰乱了肝脏生物钟节律并引发肝脏炎症反应。该研究凸显了非成像视觉通路在肝脏代谢稳态中的关键作用。

关键词：夜晚光照炎症昼夜节律肝脏

基于租房数据的京津冀城市群跨城通勤特征及影响因素研究

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地理科学进展 2024年第5期43卷 841-853页

作者：张纯马畅北京交通大学建筑与艺术学院北京100044 北京交通大学国土空间与交通协同发展研究院北京100044 北京交通大学交通运输学院北京100044

近年来中国城市群都市圈尺度的跨城通勤现象愈加频繁。相对于国际大城市的通勤圈,国内跨城通勤特征与影响因素仍不明晰。论文以京津冀城市群为例,基于贝壳App租房者的双城通勤位置数据,采用基于GIS的OD(origin-destination)分析与空间... 详细信息

近年来中国城市群都市圈尺度的跨城通勤现象愈加频繁。相对于国际大城市的通勤圈,国内跨城通勤特征与影响因素仍不明晰。论文以京津冀城市群为例,基于贝壳App租房者的双城通勤位置数据,采用基于GIS的OD(origin-destination)分析与空间统计分析,考察跨城通勤现象的空间分布特征;并辅以个体通勤时间为因变量的普通最小二乘法(ordinary least squares,OLS)、地理加权回归(geographically weighted regression,GWR)模型,揭示空间变量和个人社会属性综合作用下的影响机制。结果表明:①京津冀城市群的跨城通勤呈现出明显的廊道分布特征,集中在东部、东南与西南三条通勤廊道上;②跨城通勤距离已经超越都市圈传统研究聚焦的30~50 km范围;③跨城通勤群体占租房总量20%以上的地区,位于廊坊燕郊开发区、固安县、保定涿州市等地,形成高频通勤的“环京通勤带”;④跨城通勤个体层面的GWR回归显示了职住两地工资差异、租房价格及居住地到高铁站距离等因素对通勤时间具有空间异质性影响。长时间跨城通勤动机存在差异,部分天津跨城通勤者主要为提高居住质量和工资,而部分廊坊、保定通勤者则为了提高工资和节省房租。研究结果可为新型城镇化战略下的城市群都市圈城镇空间合理布局与综合交通协同优化提供借鉴。

关键词：城市群跨城通勤空间分布职住空间关系 GWR 京津冀

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自生黄铁矿指示海底甲烷渗漏

地球科学进展 2024年第6期39卷 589-601页

作者：张企盈苗晓明常鑫孔凡兴谷玉刘喜停中国海洋大学海洋地球科学学院海底科学与探测技术教育部重点实验室山东青岛266100 青岛海洋科技中心海洋地质过程与环境功能实验室山东青岛266237

海底甲烷渗漏是海洋环境中甲烷的重要来源,对全球碳循环和极端环境生物地球化学循环具有重要影响,示踪和重建海底(古)甲烷渗漏活动具有重要的科学意义。在甲烷渗漏活动过程中,硫酸盐驱动的甲烷厌氧氧化作用普遍发育,从而改变孔隙水地球... 详细信息

海底甲烷渗漏是海洋环境中甲烷的重要来源,对全球碳循环和极端环境生物地球化学循环具有重要影响,示踪和重建海底(古)甲烷渗漏活动具有重要的科学意义。在甲烷渗漏活动过程中,硫酸盐驱动的甲烷厌氧氧化作用普遍发育,从而改变孔隙水地球化学特征,并导致自生矿物的形成。其中,自生黄铁矿是硫酸盐驱动的甲烷厌氧氧化作用的典型自生矿物之一,可作为记录甲烷渗漏活动的良好指标。综述了硫酸盐驱动的甲烷厌氧氧化作用衍生自生黄铁矿的地球化学特征和形貌特征,评估了其在示踪和重建海底(古)甲烷渗漏活动的潜力。结果表明,自生黄铁矿的硫和铁同位素及原位微量元素和同位素可以有效识别硫酸盐驱动的甲烷厌氧氧化作用过程,甲烷渗漏环境沉积物中自生黄铁矿的形貌和含量与正常海洋沉积物存在明显差异,彰显了自生黄铁矿示踪和重建海底(古)甲烷渗漏事件的巨大潜力。

关键词：甲烷渗漏自生黄铁矿硫同位素微量元素微生物硫酸盐还原