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X射线偏振探测器中的极化光电过程模拟

光学学报 2024年第3期44卷 321-328页

作者：郑人洲强鹏飞盛立志闫永清中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室陕西西安710119

采用蒙特卡罗程序Geant4模拟2~10 keV线偏振X射线光子在几种常用工作气体中的极化光电过程,明确了光电子出射位置、方位角分布与入射光子偏振方向、能量之间的响应关系。光电子的出射方向在入射光子偏振方向上的分布概率最高,且出射光... 详细信息

采用蒙特卡罗程序Geant4模拟2~10 keV线偏振X射线光子在几种常用工作气体中的极化光电过程,明确了光电子出射位置、方位角分布与入射光子偏振方向、能量之间的响应关系。光电子的出射方向在入射光子偏振方向上的分布概率最高,且出射光电子的方位角分布可近似为余弦平方函数。光子能量增大时,各角度光电子计数不同程度地减少,但都呈现出在方位角为0或π(-π)时有极大值的统计规律。此外,揭示并量化了气体厚度、气体组成、气体体积分数之比和光子能量对探测效率的影响规律。气体厚度越大、平均原子序数越大,则探测效率越高。光子能量增大会导致探测效率降低,而对于由Xe或Ar组成的工作气体,当光子能量大于某壳层电子结合能时,由于相应壳层电子开始被弹射出,探测效率会有一定程度的提高。这些结果可为X射线偏振探测器的结构设计提供理论依据和数据支持。

关键词： X射线光学 X射线偏振探测气体探测器极化光电过程探测效率

负载型Fe-Ni纳米合金的制备及其催化丁二烯选择性加氢性能

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石油学报（石油加工） 2024年第1期40卷 83-92页

作者：严永情王朝刘思明连天王伟豪金顺敬陈丽华苏宝连武汉理工大学材料复合新技术国家重点实验室湖北武汉430070 襄阳职业技术学院湖北襄阳441050 那慕尔大学无机材料化学实验室那慕尔B-5000比利时

采用尿素沉积-沉淀法制备了负载型Fe-Ni纳米合金催化剂,通过调变Fe/Ni摩尔比,研究了金属组分对其还原温度、合金结构及催化丁二烯选择性加氢性能的影响。结果表明:Fe-Ni复合能有效降低Fe、Ni单金属催化剂的还原温度;随着Fe摩尔分数由0... 详细信息

采用尿素沉积-沉淀法制备了负载型Fe-Ni纳米合金催化剂,通过调变Fe/Ni摩尔比,研究了金属组分对其还原温度、合金结构及催化丁二烯选择性加氢性能的影响。结果表明:Fe-Ni复合能有效降低Fe、Ni单金属催化剂的还原温度;随着Fe摩尔分数由0增加至100%,金属相结构逐渐由面心立方向体心立方结构转变;在催化加氢过程中,Fe的引入降低了Ni基催化剂活性,但丁烯选择性得到大幅提高;当Fe/Ni摩尔比为25/75时,Fe_(25)Ni_(75)/TiO_(2)-R催化剂中富Ni的Ni3Fe相在丁二烯催化活性(完全转化温度T_(100%)约95℃)和单烯烃选择性(>93%)最佳。

关键词：非贵金属催化剂 Fe-Ni合金催化剂丁二烯选择性加氢低碳烯烃活性位点

Strong anisotropy of thermal transport in the monolayer of a new puckered phase of PdSe

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Frontiers of physics 2024年第3期19卷 143-151页

作者： Zheng Shu Huifang Xu Hejin yan yongqing Cai Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoTaipaMacao 999078China

We examine the electronic and transport properties of a new phase PdSe monolayer with a puckered structure calculated by first-principles and Boltzmann transport *** spin−orbit coupling is found to play a negligible effect on the electronic properties of PdSe *** lattice thermal conductivity of PdSe monolayer exhibits remarkable anisotropic characteristic due to anisotropic phonon group velocity along different directions and its intrinsic structure *** compromised electronic mobility despite a relatively low thermal conduction results in a moderate ZT value but significantly anisotropic thermoelectric performance in single-layer *** present work suggests that the remarkable thermal transport anisotropy of PdSe monolayer can be used for thermal management,and enhance the scope of possibilities for heat flow manipulation in PdSe based *** sizeable puckered cages and wiggling lattice implies it an ideal platform for ionic and molecular engineering for thermoelectronic applications.

关键词： 2D materials first-principles calculations phonon

Designing salt stress-resilient crops:Current progress and future challenges

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Journal of Integrative Plant Biology 2024年第3期66卷 303-329页

作者： Xiaoyan Liang Jianfang Li yongqing yang Caifu Jiang yan Guo State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100094China State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100194China Center for Crop Functional Genomics and Molecular Breeding China Agricultural UniversityBeijing 100094China Frontiers Science Center for Molecular Design Breeding China Agricultural UniversityBeijing 100193China

Excess soil salinity affects large regions of land and is a major hindrance to crop production ***,understanding the molecular mechanisms of plant salt tolerance has scientific importance and practical *** recent decades,studies have characterized hundreds of genes associated with plant responses to salt stress in different plant *** studies have substantially advanced our molecular and genetic understanding of salt tolerance in plants and have introduced an era of molecular design breeding of salt-tolerant *** review summarizes our current knowledge of plant salt tolerance,emphasizing advances in elucidating the molecular mechanisms of osmotic stress tolerance,salt-ion transport and compartmentalization,oxidative stress tolerance,alkaline stress tolerance,and the trade-off between growth and salt *** also examine recent advances in understanding natural variation in the salt tolerance of crops and discuss possible strategies and challenges for designing salt stress-resilient *** focus on the model plant Arabidopsis(Arabidopsis thaliana)and the four most-studied crops:rice(Oryza sativa),wheat(Triticum aestivum),maize(Zea mays),and soybean(Glycine max).

关键词： molecular design breeding salt stress-resilient crop salt tolerance

Insights into plant salt stress signaling and tolerance

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Journal of Genetics and Genomics 2024年第1期51卷 16-34页

作者： Huapeng Zhou Haifan Shi yongqing yang Xixian Feng Xi Chen Fei Xiao Honghui Lin yan Guo Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengduSichuan 610064China State Key Laboratory of Plant Environmental Resilience China Agricultural UniversityBeijing 100193China College of Grassland Science Nanjing Agricultural UniversityNanjingJiangsu 210095China Xinjiang Key Laboratory of Biological Resources and Genetic Engineering College of Life Science and TechnologyXinjiang UniversityUrumqiXinjiang 830046China

Soil salinization is an essential environmental stressor,threatening agricultural yield and ecological security *** soils accumulate excessive soluble salts which are detrimental to most plants by limiting plant growth and *** is of great necessity for plants to efficiently deal with the adverse effects caused by salt stress for survival and successful *** determinants of salt tolerance have been identified in plants,and the cellular and physiological mechanisms of plant salt response and adaption have been intensely *** respond to salt stress signals and rapidly initiate signaling pathways to re-establish cellular homeostasis with adjusted growth and cellular *** review summarizes the advances in salt stress perception,signaling,and response in plants.A better under-standing of plant salt resistance will contribute to improving crop performance under saline conditions using multiple engineering *** rhizosphere microbiome-mediated plant salt tolerance as well as chemical priming for enhanced plant salt resistance are also discussed in this review.

关键词： Salt stress Salt perception Salt response and signaling Plant salt tolerance Chemical priming Rhizosphere microbiome

Growth of C_(60)(111) single crystalline thin film on Ni_3Co(111) substrate

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Chinese Science Bulletin 1997年第18期42卷 1526-1529页

作者： HOU Jianguo, ZENG Jianlin, WANG yan, LI yongqing and WU ZiqinStructure Research Laboratory and Center for Fundamental Physics, University of Science and Technology of China, Hefei 230026, China Structure Research Laboratory anci Center for Fundamental Physics University of Science and Technology of China Hefei China

SINCE the discovery of a simple graphite-arc method which can produce grams of C60, the growth of high quality C60 films on various substrates has been one of the main subjects for fullerene research. It is reported that the growth behavior of C60 films is determined by geometrical matching and the bonding properties between C60 lattice and the surface of substrate. Much work has been done to investigate the growth and structure of C60 films on various nonmetallic substrates, such as graphite, MoS2, mica and NaCl. The interactions between C60 and nonmetallic substrates are van der Walls forces, so the growth of C60 on these

关键词： fullerene thin film growth metal substrate.

Research Progress in Glycine Betaine Improving Plant Salty Stressful Tolerance

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Journal of Northeast Agricultural University(English Edition) 2008年第4期15卷 58-62页

作者： ZHU Hong WANG Wenjie yan yongqing ZU Yuangang Department of Science and Technology Northeast Forestry University Harbin 150040 China Key Laboratory of Forestry Plant Ecology of Ministry of Education Northeast Forestry University Harbin 150040 China College of Horticulture Northeast Agricultural University Harbin 150030 China

Many plants accumulate compatible solutes in response to the imposition of environmental *** betaine, which is one of compatible solutes in cell of plants,has been shown to have surviving ability for plant from salt *** of glycine betaine on improving plant salt resistance was discussed in plants under salt *** accumulation of glycine betaine protects plants against the damaging effects of *** of glycine betaine against the damaging effects of stress were analyzed to clarify the roles of glycine betaine in salt stress tolerance of plants.

关键词： glycine betaine salt resistance environmental stress

Taxonomic Status of Daduhe Loquat （Eriobotrya prinoides var. dadunensis）

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Journal of Agricultural Science and Technology(B) 2012年第6期2卷 659-664页

作者： Wang yongqing yan Juan yang Qin Fu yan Luo Nan Lv Xiulan College of Horticulture Sichuan Agricultural University Ya'an 625014 Sichuan China

The taxonomic status of Daduhe loquat （E. prinoides var. dadunensis） was studied through analyzing genetic relationships among Oakleaf loquat （E. prinoides）, Daduhe loquat and Common loquat （E. japonica） using inter simple sequence repeats （ISSR） molecular marker and morphologic marker in this paper. Based on ISSR marker research, the similarity coefficient between Oakleaf loquat and Common loquat was lower than the similarity coefficient between Oakleaf loquat and Daduhe loquat while the similarity coefficient between Daduhe loquat and Common loquat was intermediate. The highest additivity was obtained when Daduhe loquat was regarded as the undetermined hybrid （45.8%）. The specific bands of Oakleaf loquat and Common loquat were present in Daduhe loquat. Based on morphologic traits research, Daduhe loquat was also between Oakleaf loquat and Common loquat but a little leaning to Oakleaf loquat. All the results support that Daduhe loquat was hybrid of Oakleaf loquat and Common loquat.

关键词： Common loquat Daduhe loquat genetic relationship ISSR marker morphologic traits Oakleaf loquat taxonomic status.

基于BIM的台风灾害后建筑施工关键链进度预测模型

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灾害学 2020年第2期35卷 39-43页

作者：闫永庆华北科技学院基建处河北沧州065201

及时完成台风灾害后施工项目建设,不仅可为灾区人民重建家园,也给施工企业带来一定经济效益。BIM具有强大的数据处理能力,为提高台风灾害后建筑施工关键链进度预测精度,构建基于BIM的台风灾害后建筑施工关键链进度预测模型。通过基于BI... 详细信息

及时完成台风灾害后施工项目建设,不仅可为灾区人民重建家园,也给施工企业带来一定经济效益。BIM具有强大的数据处理能力,为提高台风灾害后建筑施工关键链进度预测精度,构建基于BIM的台风灾害后建筑施工关键链进度预测模型。通过基于BIM的建筑信息子模型,提取有关台风灾害后建筑施工关键链数据,并将采集的建筑施工关键链数据实行融合,以此提高数据分析精度;再采用BIM多因素建筑施工关键链进度预测子模型,分析所获取的建筑施工关键链数据,预测台风灾害后建筑施工关键链进度。将所建立模型应用至某建筑施工关键链进度预测中,预测结果显示,该建筑施工关键链整体进度完成需要耗费14.05 d,此预测结果精准度大于0.9,预测结果有效。

关键词： BIM 台风灾害后建筑施工关键链进度预测模型