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植物硒多糖的研究与应用进展

中国野生植物资源 2024年第6期43卷 68-75页

作者：李施婵黄秀芳刘海晨湖北民族大学生物与食品工程学院湖北恩施445000

硒多糖是由硒和植物多糖通过共价键结合而成。由于其比单一的硒或多糖具有更强的生物活性和对人体健康的影响,目前已成为全球最热门的研究领域之一。然而,基于现有的研究成果,自然界中种类繁多、结构错综复杂的植物多糖难以考证。本文... 详细信息

硒多糖是由硒和植物多糖通过共价键结合而成。由于其比单一的硒或多糖具有更强的生物活性和对人体健康的影响,目前已成为全球最热门的研究领域之一。然而,基于现有的研究成果,自然界中种类繁多、结构错综复杂的植物多糖难以考证。本文通过简述近年来发现的植物硒多糖的提取方法、结构鉴定、生物活性等,并进行比较,初步推断植物硒多糖的共性和研究规律,为后续植物硒多糖的研究提供进一步的理论依据。

关键词：植物硒多糖制备方法生物活性

Enhancement of catalytic and anti-carbon deposition performance of SAPO-34/ZSM-5/quartz films in MTA reaction by Si/Al ratio regulation

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Chinese Journal of Chemical Engineering 2023年第4期56卷 314-324页

作者： Jiaxin Wu Chenxiao Wang Xianliang Meng haichen liu Ruizhi Chu Guoguang Wu Weisong Li Xiaofeng Jiang Deguang Yang School of Chemical Engineering and Technology China University of Mining&TechnologyXuzhou 221116China Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education Xuzhou 221116China

In order to further improve the catalytic performance of zeolite catalyst for methanol to aromatics(MTA)technology, the double-tier SAPO-34/ZSM-5/quartz composite zeolite films were successfully synthesized via hydrothermal crystallization. The Si/Al ratio of SAPO-34 film was used as the only variable to study this material. The composite zeolite material with 0.6Si/Al ratio of SAPO-34 has the largest mesoporous specific surface area and the most suitable acid distribution. The catalytic performance for the MTA process showed that 0.6-SAPO-34/ZSM-5/quartz film has as high as 50.3% benzene-toluenexylene selectivity and 670 min lifetime. The MTA reaction is carried out through the path we designed to effectively avoid the hydrocarbon pool circulation of ZSM-5 zeolite, so as to improve the aromatics selectivity and inhibit the occurrence of deep side reactions to a great extent. The coke deposition behavior was monitored by thermogravimetric analysis and gas chromatograph/mass spectrometer, it is found that with the increase of Si/Al ratio, the active intermediates changed from low-substituted methylbenzene to high-substituted methylbenzene, which led to the rapid deactivation of the catalyst. This work provides a possibility to employ the synergy effect of composite zeolite film synthesizing anti-carbon deposition catalyst in MTA reaction.

关键词： Composite zeolite film Methanol to aromatics Anti-carbon deposition Si/Al ratio Hydrocarbon pool circulation mechanism

弱交变磁场辅助晶界扩散增强烧结钕铁硼磁体矫顽力

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内蒙古大学学报（自然科学版） 2024年第3期55卷 273-280页

作者：吕燕武吕军刘海晨房漠楠黄二愿内蒙古工业大学材料科学与工程学院呼和浩特010051 内蒙古自治区薄膜与涂层重点实验室呼和浩特010051 内蒙古工业大学理学院呼和浩特010051 包头品高永磁材料有限公司内蒙古包头014030

采用物理气相沉积工艺在商用N35级烧结钕铁硼磁体表面沉积0.3 wt%的镝金属,并在910℃的热处理过程中施加频率为50 Hz的弱磁场,研究了弱交变磁场辅助晶界扩散对磁体矫顽力的影响。磁性能测试显示,相比于原始磁体,常规扩散和0.3 T弱交变... 详细信息

采用物理气相沉积工艺在商用N35级烧结钕铁硼磁体表面沉积0.3 wt%的镝金属,并在910℃的热处理过程中施加频率为50 Hz的弱磁场,研究了弱交变磁场辅助晶界扩散对磁体矫顽力的影响。磁性能测试显示,相比于原始磁体,常规扩散和0.3 T弱交变磁场辅助扩散的矫顽力分别增加了3.28 kOe和5.02 kOe。基于扫描电镜图像,使用ImageJ软件分析了扩散磁体中的粒径分布,发现与原始磁体的平均粒径相比,磁场辅助扩散过程中晶粒没有进一步长大,但常规扩散磁体的平均粒径却增长了约0.5μm。能量色散光谱仪线扫描结果显示,在距磁体镀镝表面400~1500μm范围内,磁场辅助扩散磁体的镝含量明显高于常规扩散。结果表明,弱交变磁场辅助晶界扩散能够有效抑制晶粒长大和增加镝元素沿晶界扩散的深度;磁体矫顽力的提升应归因于这些效应的叠加。实验结果为进一步优化烧结钕铁硼磁体晶界扩散工艺提供了新方案。

关键词：钕铁硼晶界扩散磁场辅助矫顽力

Single zircon dating by LAM-ICPMS technique

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Chinese Science Bulletin 1999年第2期44卷 182-186页

作者： haichen liu Bingquan Zhu Zhanxia Zhang Chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510640 Peoples R China Zhongshan Univ Dept Chem Guangzhou 510275 Peoples R China

A UV laser ablation microprobe-inductively coupled plasma mass spectrometry （LAMICPMS） is used to determine the Pb/Pb and Pb/U ages of several zircon grains whose ages have been measured by the conventional U-Pb thermal ionization mass spectrometry （TIMS） method. The mass fractionation factor of Pb isotope ratio was typically between 0.010--0.012 and corrected by NIST610 glass standard. Several factors that influence the stability of Pb/U ratio have been investigated and optimized. The precision of 207pb/206Pb and （206）pb/238U from each sampling crater is within 0.6%—2.4% and 1%—10% respectively, while the precision for the average of mean ratios from different craters is 0.7% and 6% correspondingly. The 207)Pb/206pb and 206pb/238U age differences compared with TIMS results are 《1% and <3% respectively.

关键词： laser ablation microprobe ICP-MS zircon geochronology.

嵌套高分辨率网格对我国东南沿海登陆台风模拟的影响

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东华大学学报（自然科学版） 2024年第2期50卷 181-189页

作者：邬贤文陈勇航魏煜郑运霞孙琳琳马骁骏辛渝赵兵科刘海晨李金乐李纤宁东华大学环境科学与工程学院上海中国气象局上海台风研究所上海复旦大学大气与海洋科学系上海中国气象局乌鲁木齐沙漠气象研究所新疆乌鲁木齐中山大学海洋工程与技术学院广东珠海

嵌套高分辨率网格对台风模拟有十分重要的影响。基于COAWST(coupled ocean atmosphere wave sediment transport)模式,针对登陆广东、海南的11个台风,设计了2组模拟方案。一组是在9 km分辨率下嵌套3 km分辨率网格,另一组是采用单层9 km... 详细信息

嵌套高分辨率网格对台风模拟有十分重要的影响。基于COAWST(coupled ocean atmosphere wave sediment transport)模式,针对登陆广东、海南的11个台风,设计了2组模拟方案。一组是在9 km分辨率下嵌套3 km分辨率网格,另一组是采用单层9 km分辨率网格。将模拟结果与中国气象局热带气旋资料中心发布的最佳路径数据进行对比,以探讨嵌套高分辨率网格是否可以提高台风模拟的准确性。从台风路径的模拟结果来看,在9 km分辨率下嵌套3 km分辨率网格对台风路径模拟的误差较小,而单层9 km分辨率网格模拟的台风路径误差较大。通过对比两组方案模拟的台风路径、强度和结构,在模拟区域中使用嵌套高分辨率网格方案的模拟准确性有所提高。两种方案模拟的风场以及副热带高压十分接近。相比于单层网格,嵌套了高分辨率网格方案模拟的台风路径、强度误差更小,台风眼更小,位涡更强。

关键词：高分辨率网格台风模拟 COAWST模式台风路径台风强度台风结构

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想象让感知得以流动——关于绘画的四个话题

美术 2022年第10期 62-65页

作者：刘海辰四川美术学院版画系

我的艺术道路是从创作铜版画开始的,本科和研究生阶段的创作都围绕铜版画展开。长时间对版画的学习,既让我不断深入探索了绘画本身,又通过媒介感知为我的创作提供了很多灵感。铜版画有别于绘画,具有强烈的工序性、间接性。一幅画的实现... 详细信息

我的艺术道路是从创作铜版画开始的,本科和研究生阶段的创作都围绕铜版画展开。长时间对版画的学习,既让我不断深入探索了绘画本身,又通过媒介感知为我的创作提供了很多灵感。铜版画有别于绘画,具有强烈的工序性、间接性。一幅画的实现,涉及技术性的把握、多重的反转和语言的想象。

关键词：铜版画研究生阶段一幅画绘画技术性间接性想象

叶面喷施钙肥对春玉米茎秆抗倒伏特性与产量形成的影响

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作物杂志 2024年第3期 223-230页

作者：徐荣琼张翼飞杜嘉瑞尹雪巍杨克军孙逸珊李泽松李桂彬陆雨欣刘海晨李伟庆李佳宇黑龙江八一农垦大学农学院/黑龙江省现代农业栽培技术与作物种质改良重点实验室黑龙江大庆163319 农业农村部东北平原农业绿色低碳重点实验室黑龙江大庆163319 北大荒现代农业产业技术省级培育协同创新中心黑龙江大庆163319

为探究叶面喷施钙肥对玉米茎秆抗倒伏性能及产量形成的调控作用机制,选用盆栽试验,以玉米品种先玉335为供试材料,分别设置0(LCK)、3(LC1)、6(LC2)、9(LC3)和12 g/L(LC4)5个钙浓度处理,于玉米拔节期进行叶面喷施。结果表明,与LCK相比,LC... 详细信息

为探究叶面喷施钙肥对玉米茎秆抗倒伏性能及产量形成的调控作用机制,选用盆栽试验,以玉米品种先玉335为供试材料,分别设置0(LCK)、3(LC1)、6(LC2)、9(LC3)和12 g/L(LC4)5个钙浓度处理,于玉米拔节期进行叶面喷施。结果表明,与LCK相比,LC2处理可显著降低玉米穗位高和重心高度,拔节期喷施适量钙肥(LC2和LC3)显著增加了茎秆基部抗折力和穿刺强度。叶面施钙可促进硬皮组织和维管束的发育,并且能显著提高玉米第3节间茎秆可溶性糖、纤维素和半纤维含量,且均在LC3处理下达最大值。叶面喷施LC2~LC4水平的钙肥也可明显提升玉米籽粒产量,其中LC2穗行数最大,为16.35,LC3处理百粒重最高,达31.36 g。从玉米茎秆的各项抗倒伏性能指标、茎秆化学成分及籽粒产量构成等综合表现来看,玉米叶片喷施钙肥最佳浓度范围为6~9 g/L,可以有效缩短基部节间长度,降低穗位高,促使玉米重心高度下移,同时优化茎秆中的氮、钾含量和纤维结构,促进维管束的发育,有效提高节间密度和充实度,进而提升茎秆机械强度,同时也能促进果穗发育,增加穗行数和百粒重和玉米产量。

关键词：玉米钙肥叶面喷施抗倒伏特性产量

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High resolution Porites Mg/Ca thermometer for the north of the South China Sea

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Chinese Science Bulletin 1999年第3期44卷 273-276页

作者： Gangjian Wei Xianhua Li Baofu Nie Min Sun haichen liu Chinese Acad Sci Guangzhou Inst Geochem Canton 510640 Peoples R China Chinese Acad Sci S China Sea Inst Oceanol Guangzhou 510310 Peoples R China Univ Hong Kong Dept Earth Sci Hong Kong Peoples R China

High resolution Mg/Ca ratios in the skeleton of a Porites lutea from the coastal area in the North of the South China Sea were precisely analyzed by ICP-MS. Compared with the instrument measured SST records, the Mg/Ca ratios strongly correlate with the SSTs, even in time of 1982/83 EI N(?)io. Therefore, a coral Mg/Ca thermometer for the North of the South China Sea was *** on ICP-MS technique it can report sea surface temperatures to an accuracy of±0.5℃.

关键词： Porites lutea Mg/Ca thermometer North of the South China Sea.

Expert Experience and Data-Driven Based Hybrid Fault Diagnosis for High-SpeedWire Rod Finishing Mills

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1827-1847页

作者： Cunsong Wang Ningze Tang Quanling Zhang Lixin Gao haichen Yin Hao Peng Institute of Intelligent Manufacturing Nanjing Tech UniversityNanjing210009China Beijing Gaohuahan Intelligent Technology Co. Ltd.Beijing100084China BeijingWavelet Rhythm Technology Co. Ltd.Beijing100020China College of Mechanical and Power Engineering Nanjing Tech UniversityNanjing211816China

The reliable operation of high-speed wire rod finishing mills is crucial in the steel production *** complex system-level equipment,it is difficult for high-speed wire rod finishing mills to realize fault location and real-time *** solve the above problems,an expert experience and data-driven-based hybrid fault diagnosis method for high-speed wire rod finishing mills is proposed in this ***,based on its mechanical structure,time and frequency domain analysis are improved in fault feature *** approach of combining virtual value,peak value with kurtosis value index,is adopted in time domain *** adjustment and side frequency analysis are proposed in frequency domain analysis to obtain accurate component characteristic frequency and its corresponding ***,according to time and frequency domain characteristics,fault location based on expert experience is proposed to get an accurate fault ***,the proposed method is implemented in the equipment intelligent diagnosis *** taking an equipment fault on site,for example,the effectiveness of the proposed method is illustrated in the system.

关键词： High-speed wire rod finishing mills expert experience data-driven fault diagnosis