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富硒食品中元素硒检测技术的应用研究进展

盐科学与化工 2024年第4期53卷 9-13页

作者：吕洪亮张美燕张永和刘欣刘文彬和布克赛尔蒙古自治县宏达盐业有限责任公司新疆塔城834406

硒在人体中具有重要作用,参与人体抗氧化、免疫调节、甲状腺功能等多个生理过程。因此,科学检测富硒食品中的硒含量对于保障人们的营养和健康至关重要。文章主要介绍了富硒食品中元素硒含量常用的检测方法:氢化物发生—原子荧光光谱法... 详细信息

硒在人体中具有重要作用,参与人体抗氧化、免疫调节、甲状腺功能等多个生理过程。因此,科学检测富硒食品中的硒含量对于保障人们的营养和健康至关重要。文章主要介绍了富硒食品中元素硒含量常用的检测方法:氢化物发生—原子荧光光谱法、电感耦合等离子体发射光谱法、电感耦合等离子体质谱法、原子吸收光谱法、荧光分光光度法等测试方法的原理、应用及特点,指出未来硒测试朝着多方法集成的方向发展,以期为富硒食品中元素硒的检测提供借鉴。

关键词：富硒食品硒元素检测方法

聚吡咯-苯胺/石墨烯/二氧化硅复合薄膜的制备及其防腐性能研究

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广东化工 2024年第12期51卷 17-20,10页

作者：李东东张永合李芸菲李文雅兰州资源环境职业技术大学甘肃兰州730021

本文利用电化学制备了三元复合薄膜P(ANI/Py)/RGO/SiO_(2),找到了一种电化学制备三元复合薄膜的方法。同时对比一元薄膜P(ANI/Py)、二元P(ANI/Py)/SiO_(2)薄膜研究其抗腐蚀性能,发现在量0.025 mo1/L苯胺0.075 mo1/L吡咯得到的三元复合... 详细信息

本文利用电化学制备了三元复合薄膜P(ANI/Py)/RGO/SiO_(2),找到了一种电化学制备三元复合薄膜的方法。同时对比一元薄膜P(ANI/Py)、二元P(ANI/Py)/SiO_(2)薄膜研究其抗腐蚀性能,发现在量0.025 mo1/L苯胺0.075 mo1/L吡咯得到的三元复合薄膜有较好的防腐蚀性能。测试腐蚀电位为-0.535 V,腐蚀电流1.828×10^(-9)A·cm^(-2)。

关键词：电化学聚合导电聚合物防腐

Numerical simulation of flow field deposition and erosion characteristics around bridge-road transition section

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Journal of Mountain Science 2024年第5期21卷 1491-1508页

作者： zhang Kai WANG Zhenghui WANG Tao TIAN Jianjin zhang Hailong LIU yonghe College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Wind-sand flow generates erosion and deposition around obstacles such as bridges and roadbeds, resulting in sand damage and endangering railway systems in sandy regions. Previous studies have mainly focused on the flow field around roadbeds, overlooking detailed examinations of sand particle erosion and deposition patterns near bridges and roadbeds. This study employs numerical simulations to analyze the influence of varying heights and wind speeds on sand deposition and erosion characteristics at different locations: the bridge-road transition section(side piers), middle piers, and roadbeds. The results show that the side piers, experience greater accumulation than the middle piers. Similarly, the leeward side of the roadbed witnesses more deposition compared to the windward side. Another finding reveals a reduced sand deposition length as the vertical profile, in alignment with the wind direction, moves further from the bridge abutments at the same clearance height. As wind speeds rise, there’s a decline in sand deposition and a marked increase in erosion around the side piers, middle piers and roadbeds. In conclusion, a bridge clearance that’s too low can cause intense sand damage near the side piers, while an extremely high roadbed may lead to extensive surface sand deposition. Hence, railway bridges in areas prone to sandy winds should strike a balance in clearance height. This research provides valuable guidelines for determining the most suitable bridge and roadbed heights in regions affected by wind and sand.

关键词： Sandstorm Flow field Bridge-road transition section Sedimentation erosion Numerical simulation

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含硒结晶盐富硒实验研究

盐科学与化工 2024年第3期53卷 22-25页

作者：吕洪亮张永和张美燕毛旭林王雪枫和布克赛尔蒙古自治县宏达盐业有限责任公司新疆塔城834400 新疆煤炭清洁转化与化工过程重点实验室新疆大学化工学院新疆乌鲁木齐830017

硒对人体健康有着积极促进作用,天然盐湖产出的含硒盐硒含量达不到富硒盐标准,采用浸润法在80℃下含硒盐中分批加入浓缩含硒卤水并不断搅拌,在100℃下干燥,可明显减少团块的出现。含硒卤水加入量为10mL/100g时硒含量可达到富硒标准以上。

关键词：硒氯化钠含硒卤水

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结构突变航天器惯量参数在轨辨识方法

航天控制 2024年第4期42卷 71-77页

作者：许诺夏喜旺贺雄峰范城城李照雄张永合中国科学院微小卫星创新研究院上海201203 中国科学院卫星数字化技术重点实验室上海201203 中国科学院大学北京100049

针对在轨服务的航天器惯量参数突变情况,提出了基于卫星在轨姿态测量及控制信息实现惯量参数实时辨识的方法,设计了递推最小二乘(RLS)及扩展卡尔曼滤波(EKF)辨识算法。在RLS算法中引入自适应遗忘因子,每次递推过程中通过分配先验数据和... 详细信息

针对在轨服务的航天器惯量参数突变情况,提出了基于卫星在轨姿态测量及控制信息实现惯量参数实时辨识的方法,设计了递推最小二乘(RLS)及扩展卡尔曼滤波(EKF)辨识算法。在RLS算法中引入自适应遗忘因子,每次递推过程中通过分配先验数据和当前数据的权重确保产生突变后辨识值的及时跟踪;在EKF算法中明确先验预测协方差中参数变化的影响,将其代入更新预测协方差矩阵以应对惯量参数的突变。仿真结果表明,考虑惯量参数突变的场景,RLS算法和EKF算法的辨识精度可达1.5%和1%,辨识时间分别优于30 s和40 s;考虑惯量缓慢时变的场景,两种方法均可实现惯量参数的在轨实时辨识,辨识精度满足姿控系统需求。

关键词：结构突变航天器自适应递推最小二乘扩展卡尔曼滤波参数在轨辨识

Les droits de l'homme sont un concept ouvert

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今日中国（法文版） 2022年第7期60卷 40-42页

作者： zhang yonghe Institut de recherche sur les droits de l'homme relevant de l'Université des sciences politiques et du droit du Sud-Ouest

Le président chinois Xi Jinping a indiqué que les droits de l'homme sont historiques,concrets et réalistes,et qu’il ne faut pas les définir indépendamment des conditions sociopolitiques ainsi que des traditions historiques et culturelles des différents pays.C’est la meilleure explication de la logique de développement des droits de l’homme.

关键词： des son les

Orbital reference frame estimation with power spectral density constraints for drag-free satellites

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Chinese Journal of Aeronautics 2016年第6期29卷 1721-1729页

作者： zhang yonghe Wang Yamin Mao Qingyun Liang Xuwen Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China Shanghai Engineering Centre for Microsatellites Shanghai 201210China Joint Key Laboratory of Microsatellite Chinese Academy of SciencesShanghai 201210China

The drag-free satellites are widely used in the field of fundamental science as they enable the high-precision measurement in pure gravity fields. This paper investigates the estimation of local orbital reference frame(LORF) for drag-free satellites. An approach, taking account of the combination of the minimum estimation error and power spectral density(PSD) constraint in frequency domain, is proposed. Firstly, the relationship between eigenvalues of estimator and transfer function is built to analyze the suppression and amplification effect on input signals and obtain the eigenvalue range. Secondly, an optimization model for state estimator design with minimum estimation error in time domain and PSD constraint in frequency domain is established. It is solved by the sequential quadratic programming(SQP) algorithm. Finally, the orbital reference frame estimation of low-earth-orbit satellite is taken as an example, and the estimator of minimum variance with PSD constraint is designed and analyzed using the method proposed in this paper.

关键词： Drag-free satellite Orbital reference frame Power spectral density State estimation Transfer function

Concept of the Solar Ring mission: Preliminary design and mission profile

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Science China(Technological Sciences) 2021年第1期64卷 131-138页

作者： WANG YaMin CHEN Xin WANG PengCheng QIU ChengBo WANG YuMing zhang yonghe Innovation Academy for Microsatellites Chinese Academy of Sciences(CAS)Shanghai 201203China Key Lab of Microsatellite Chinese Academy of SciencesShanghai 201203China Shanghai Engineering Center for Microsatellites Shanghai 201203China CAS Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology University of Science and Technology of ChinaHefei 230026China

The Solar Ring mission, a concept to monitor the Sun and inner heliosphere from multiple perspectives, has been funded for prephase study by the Strategic Priority Program of Chinese Academy of Sciences in space sciences. The Solar Ring is comprised of 6 spacecraft, grouped in three pairs, moving around the Sun in an elliptical orbit in the ecliptic plane. The mission costs,including launch fee, deep-space maneuvers, and deployment time of the ring, are highly relevant to the working orbit, deepspace transfer, and phase angle within a group. The preliminary mission profile is analyzed and designed in this paper. The launch way, two spacecraft with one rocket, is adopted. The deployment time, phasing maneuvers, and C_(3) of launch energy are evaluated for the elliptical orbits with the perihelion between 0.7 and 0.9 AU using the rockets of Long March(LM) 3A and *** simulations show two candidate trajectories: fast deployment within 4 years by LM-3B, medium deployment more than 6 years by cheaper rocket of LM-3A. In order to obtain both fast deployment and low launch cost, another orbit profile is proposed by shortening the phase angle within a group. The suggested working orbits and the corresponding costs of launch,deployment time, and phasing maneuvers will strongly support the science objectives.

关键词： solar and heliospheric observations deep-space transfer orbit optimization

高比表面积3YSZ粉体注射成型工艺参数优化及制品力学性能

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内蒙古科技大学学报 2024年第1期43卷 20-25页

作者：高雄张永和包金小王青春阮飞李阳毛大伟宋希文内蒙古科技大学材料与冶金学院内蒙古包头014010

为解决高比表面积的3YSZ陶瓷粉末难以应用于注射成型工艺的问题,以比表面积为18 m^(2)/g的3YSZ陶瓷粉末为原料,以生坯质量为正交试验的评价标准,优化得到了最优注射参数,并对烧结制品的力学性能进行了研究。结果表明:参数影响力的顺序... 详细信息

为解决高比表面积的3YSZ陶瓷粉末难以应用于注射成型工艺的问题,以比表面积为18 m^(2)/g的3YSZ陶瓷粉末为原料,以生坯质量为正交试验的评价标准,优化得到了最优注射参数,并对烧结制品的力学性能进行了研究。结果表明:参数影响力的顺序为注射压力>保压时间>注射速度>注射温度,适用于该粉体的最优注射参数为注射温度165℃,注射压力110 kg,注射速度为85 g/s,在70 kg下保压1 s。将使用该工艺得到的生坯脱脂后,于1350℃下烧结即可得到相对密度为98.5%,维氏硬度为13.42 GPa,断裂韧性为6.47 MPa·m^(1/2)的四方多晶氧化锆陶瓷。

关键词：正交试验粉末比表面积陶瓷注射成型 3YSZ