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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

Prediction of Th17/Treg cell balance on length of stay in intensive care units of patients with sepsis

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Journal of Intensive Medicine 2024年第2期4卷 240-246页

作者： Yu Wu Guosheng Wu Minyu Li yongqing Chang Miao Yu yan Meng Xiaojian Wan Department of Intensive Care Medicine Changhai HospitalNaval Medical UniversityShanghaiChina Department of Anesthesiology Bethune International Peace HospitalShijiazhuangHebeiChina Department of Burns Changhai HospitalNaval Medical UniversityShanghaiChina Department of Special Needs Clinic Changhai HospitalNaval Medical UniversityShanghaiChina

Background Prolonged length of stay(LOS)of sepsis can drain a hospital's material and human *** study investigated the correlations between T helper type 17(Th17)and regulatory T(Treg)balance with LOS in *** A prospective clinical observational study was designed in Changhai Hospital affiliated to Naval Medical University in Shanghai,China,from January to October *** patients diagnosed with sepsis and who met the inclusion and exclusion criteria were recruited and whether the levels of cytokines,procalcitonin,subtypes,and biomarkers of T cells in the peripheral blood were *** analyzed the correlation between these and *** Sixty septic patients were classified into two groups according to whether their intensive care unit(ICU)stay exceeded 14 *** patients with LOS≥14 days were older([72.6±7.5]years vs.[63.3±10.4]years,P=0.015)and had higher Sequential Organ Failure Assessment(SOFA)(median[interquartile range]:6.5[5.0–11.0]vs.4.0[3.0–6.0],P=0.001)and higher Acute Physiology and Chronic Health Evaluation(APACHE)II scores(16.0[13.0–21.0]vs.8.5[7.0–14.0],P=0.001).There was no difference in other demographic characteristics and cytokines,interleukin-6,tumor necrosis factor-α,and interleukin-10 between the two *** Th17/Treg ratio of sepsis with LOS<14 days was considerably lower(0.48[0.38–0.56]vs.0.69[0.51–0.98],P=0.001).For patients with LOS≥14 days,the area under the receiver operating characteristic curve for the Th17/Treg ratio was *** improved to 0.840 and 0.850 when combined with the SOFA and APACHE II scores,*** The Th17/Treg ratio was proportional to septic severity and can be used as a potential predictor of ICU stay in sepsis,presenting a new option for ICU practitioners to better care for patients with sepsis.

关键词： Sepsis Th17/Treg Length of stay Intensive care units

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软岩构造破碎带巷道支护技术应用

山东煤炭科技 2023年第4期41卷 52-53,57页

作者：闫永青长春兴煤业有限公司山西大同037101

基于长春兴煤矿西翼回风大巷掘进过断层期间巷道顶板破碎,分析了原支护设计主要存在的问题,提出了“注浆+锚索梁棚+自锁式锚杆”联合支护设计。通过实际应用效果来看,采取联合支护技术后围岩单轴抗压强度提高至45.6 MPa,顶板最大下沉量... 详细信息

基于长春兴煤矿西翼回风大巷掘进过断层期间巷道顶板破碎,分析了原支护设计主要存在的问题,提出了“注浆+锚索梁棚+自锁式锚杆”联合支护设计。通过实际应用效果来看,采取联合支护技术后围岩单轴抗压强度提高至45.6 MPa,顶板最大下沉量为0.12 m,取得了显著应用成效。

关键词：软岩巷道构造支护

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103综采面俯斜法过断层施工工艺

江西煤炭科技 2022年第4期 91-93,96页

作者：闫永青长春兴煤业有限公司山西大同037101

针对103工作面采用强行破岩法过F_(2)断层时回采效率低、设备故障率高、煤柱损失等技术难题,长春兴煤矿通过技术研究,采用“俯斜法”合理优化回采工艺,并在过断层期间采取“迈步式锚索梁棚+超前管棚”联合支护顶板,现场应用效果表明:采... 详细信息

针对103工作面采用强行破岩法过F_(2)断层时回采效率低、设备故障率高、煤柱损失等技术难题,长春兴煤矿通过技术研究,采用“俯斜法”合理优化回采工艺,并在过断层期间采取“迈步式锚索梁棚+超前管棚”联合支护顶板,现场应用效果表明:采取俯斜法回采工艺后,工作面过断层期间,减少了破岩量3177 m^(3),煤柱回采率提高了5%;同时采用联合支护技术后,保证了工作面俯斜回采安全,防止了端面破碎现象。

关键词：综采工作面过断层俯斜回采联合支护

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.