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On the Mechanism of a Terrain-Influenced Snow Burst Event during Midwinter in Northeast China

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Advances in Atmospheric Sciences 2021年第5期38卷 800-816页

作者： na LI Baofeng JIAO Lingkun RAN Xinyong SHEN Yanbin QI Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China Jilin Weather Modification Office Changchun 130062China

Short-duration snow bursts with heavy snow represent one type of hazardous weather in winter which can be easily missed by the winter weather warnings but often results in great *** this paper,the mechanism for the occurrence of such events was investigated with the aid of a localized terrain-influenced snow burst event in Northeast *** snow burst was produced by an eastward-moving cold-frontal snowband which encountered the downstream complex terrain of the Changbai Mountains and *** ascertain the role of orography on the snow burst,numerical experiments,together with a parallel sensitivity experiment removing Changbai Mountains,were performed to attempt to distinguish the contributions of cold-frontal system and orographic effects to produce the heavy *** showed that without the influence of Changbai Mountains,the release of conditional instability(CI)and inertial instability(II)within a weak frontogenetical environment was responsible for the snowband *** effects played important roles in enhancing the snowband and increasing the snowfall *** enhancement mechanism was related to the interactions of the cold-frontal snowband and the *** the one hand,orographic frontogenesis and persistent ascent,created by orographic gravity waves over the terrain,greatly enhanced the orographic *** intensification of the lifting promoted the release of CI and thus enhanced the *** the other hand,pre-existing orographic instabilities were released due to the passing of the cold-frontal snowband,which could also serve to intensify the snowband over terrain and thus increase the snowfall.

关键词： terrain-influenced snow burst snowband instability lifting

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嵌段共聚物电解质的制备及其电化学性能

材料工程 2024年第6期52卷 69-77页

作者：张锟刘娜田君梁晓嫱陈光海高洪波胡道中佟蕾田崔钧王浩辰中国北方车辆研究所北京100072 北京卫蓝新能源科技有限公司北京102402

通过设计聚合物分子结构,采用热引发自由基聚合方法合成聚乙二醇甲醚甲基丙烯酸酯(PEGMEMA)和甲基丙烯酸缩水甘油酯(GMA)的二嵌段共聚物电解质PEGMEMAm-GMAn-Br(PGA-Br),并研究其电化学性能。结果表明:将PGA嵌段或接枝到聚合物电解质上... 详细信息

通过设计聚合物分子结构,采用热引发自由基聚合方法合成聚乙二醇甲醚甲基丙烯酸酯(PEGMEMA)和甲基丙烯酸缩水甘油酯(GMA)的二嵌段共聚物电解质PEGMEMAm-GMAn-Br(PGA-Br),并研究其电化学性能。结果表明:将PGA嵌段或接枝到聚合物电解质上,可提高聚合物电解质的离子电导率,室温下的离子电导率达1.05×10^(−4)S·cm^(−1)。同时,PGA-Br嵌段共聚物电解质具有较低的玻璃化转变温度(-65℃)、较高的热分解温度、较宽的电化学稳定窗口(5.1 V)和阻燃特性。PGA-Br共聚物电解质组装下的固态Li|Li对称电池具有增强的电极/电解质固-固界面,可实现金属锂均匀沉积,有效抑制锂枝晶的生长。在0.1 C倍率下,基于PGA-Br嵌段共聚物电解质组装的LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)|PGA-Br|Li固态全电池可实现较高的首周放电比容量(160.1 mAh·g^(−1)),且循环100周次后容量保持率高达91.5%,库仑效率稳定在98.5%以上。

关键词：固态锂金属电池嵌段共聚物电解质锂金属负极锂枝晶热引发聚合

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Preparation of sol-gel derived microcrystalline corundum abrasives with hexagonal platelets

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International Journal of Minerals,Metallurgy and Materials 2013年第1期20卷 71-75页

作者： na Li Yu-Mei Zhu Kai Gao Zhi-Hong Li Key Laboratory of Advanced Ceramics and Machining Technology School of Materials Science and Engineering Tianjin University

The effects of different additives on the mechanical properties, microstructures, and wear behavior of corundum abra- sives were investigated. When the number of additive phases increases, the sintering temperature and wear rate decrease, while the densification and mechanical properties increase. The additive SiO2 is responsible for the development of equiaxed grains, whereas both CaO and MgO promote the development of platelike grains. By controlling the molar ratio of additives, it is pos- sible to obtain different microstructures. With SiO2-MgO-CaO （molar ratio, 2：1：1） as the additives and nano a-Al203 powders as the seed, microcrystalline corundum abrasives with hexagonal platelets were obtained using sol-gel process by sintering at 1300℃ for 0.5 h. The average diameter and thickness of hexagonal platelets are 1.38 μm and 360 nm respectively, the sin- gle-particle compressive strength is 26.44 N, and the wear rate is （3.06±=0.21）× 10^-7 mm^3/（N.m）.

关键词： additives corundum microcrystals sol-gel process platelets compressive strength wear

Defect energetics and magnetic properties of 3d-transition-metal-doped topological crystalline insulator SnTe

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Science China(Physics,Mechanics & Astronomy) 2016年第8期59卷 16-21页

作者： na Wang JianFeng Wang Chen Si Bing-Lin Gu WenHui Duan Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics Tsinghua University School of Materials Science and Engineering Beihang University Institute for Advanced Study Tsinghua University Collaborative Innovation Center of Quantum Matter Tsinghua University

The introduction of magnetism in SnTe-class topological crystalline insulators is a challenging subject with great importance in the quantum device applications. Based on the first-principles calculations, we have studied the defect energetics and magnetic properties of 3d transition-metal(TM)-doped SnTe. We find that the doped TM atoms prefer to stay in the neutral states and have comparatively high formation energies, suggesting that the uniform TMdoping in SnTe with a higher concentration will be difficult unless clustering. In the dilute doping regime, all the magnetic TMatoms are in the high-spin states, indicating that the spin splitting energy of 3d TM is stronger than the crystal splitting energy of the SnTe ligand. Importantly, Mn-doped SnTe has relatively low defect formation energy, largest local magnetic moment, and no defect levels in the bulk gap, suggesting that Mn is a promising magnetic dopant to realize the magnetic order for the theoretically-proposed large-Chern-number quantum anomalous Hall effect(QAHE) in SnTe.

关键词： topological crystalline insulator transition metal doping SnTe defect formation energy magnetic moment

Effect of organic amendment amount on soil nematode community structure and metabolic footprints in soybean phase of a soybean-maize rotation on Mollisols

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Pedosphere 2020年第4期30卷 544-554页

作者： Fengjuan PAN Xiaozeng HAN na LI Jun YAN Yanli XU national Observation Station of Hailun Agro-ecology System Key Laboratory of Mollisols AgroecologyNortheast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081(China)

It has been well documented that organic amendment affects soil nematode community ***,little is known about the effect of organic amendment amount on soil *** assess the effect of the amount of organic amendments on soil nematode community structure and metabolic activity,the community composition,abundance,and metabolic footprints of soil nematodes were determined in a long-term field experiment with various amounts of organic amendment in Northeast *** treatments included an unfertilized control(CK),chemical fertilizer without manure amendment(OM0),manure applied at 7.5 Mg ha^-1 plus chemical fertilizer(OM1),and manure applied at 22.5 Mg ha^-1 plus chemical fertilizer(OM2).A total of 46 nematode genera were *** with the largest amount of organic amendment had the smallest number of plant parasite genera(5),but a largest number of dominant genera(7).Soil nematodes,bacterivores,and fungivores were the most abundant in OM2,followed by OM1,and the lowest in OM0 and *** amendment increased the enrichment index(EI),and the large amount of organic amendment increased the metabolic footprints of bacterivore(Baf)and fungivore(Fuf)and enrichment footprint(Ef).The relationships between Baf(or Fuf)and the increases in soil organic carbon(?SOC)and total nitrogen(?TN)were stronger than those of bacterivore(or fungivore)abundance with?SOC and?TN,except for the relationship between bacterivore abundance and ?*** EI and Ef were positively correlated with ?SOC and ?*** findings suggest that the amount of organic amendment affects soil nematode activity and function at entry levels in soil food web,and that metabolic footprints of soil nematodes may be better indicators than their abundances in assessing their relationships with soil nutrients.

关键词： community composition ecosystem function enrichment footprint enrichment index metabolic activity soil food web trophic group

改良T组合复苏器与鼻导管吸氧用于婴儿电子支气管镜检查的安全性比较:一项前瞻性随机对照研究

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中国当代儿科杂志 2024年第1期26卷 37-41页

作者：宁俊杰左智惠喻志东李雪梅乔莉娜自贡市第一人民医院儿科四川自贡643000 四川大学华西第二医院儿童重症医学科四川成都610041 国家卫生健康委员会时间生物学重点实验室(四川大学) 四川成都610041 出生缺陷与相关妇儿疾病教育部重点实验室四川成都610041

目的优化肺部疾病婴儿接受支气管镜检查时的氧疗方案。方法该研究是一项前瞻性随机、对照的单中心临床试验。前瞻性选择2019年7月—2021年7月42例接受电子支气管镜检查的婴儿为研究对象。按照随机数字表法分为鼻导管吸氧(nasal cannula ... 详细信息

目的优化肺部疾病婴儿接受支气管镜检查时的氧疗方案。方法该研究是一项前瞻性随机、对照的单中心临床试验。前瞻性选择2019年7月—2021年7月42例接受电子支气管镜检查的婴儿为研究对象。按照随机数字表法分为鼻导管吸氧(nasal cannula oxygen,NC)组及改良T组合复苏器(T-piece resuscitator,TPR)组。记录两组术中最低血氧饱和度结果作为主要指标,术中心率及呼吸结果作为次要指标。结果改良TPR组术中最低血氧饱和度高于NC组,低氧血症发生率低于NC组(P0.05)。结论改良TPR可以显著减少肺部疾病婴儿接受电子支气管镜时发生低氧血症的风险;与传统NC相比,TPR可明显改善低氧血症的严重程度,且减少呼吸节律异常的发生率。

关键词： T组合复苏器鼻导管吸氧电子支气管镜临床效果婴儿

Epigenetic changes in the regulation of carotenoid metabolism during honeysuckle flower development

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Horticultural Plant Journal 2023年第3期9卷 577-588页

作者： Hang Yu na Cui Kun Guo Wen Xu Haifeng Wang State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangxi Key Lab of Sugarcane BiologyCollege of AgricultureGuangxi UniversityNanningGuangxi 530005China Institute of Medicinal Plant Development Chinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100193China Innovation and Transformation Center of Science and Technology College of PharmacyFujian University of Traditional Chinese MedicineFuzhouFujian 350122China

Flower development is one of the most vital pathways in plant development, during which the epigenetic regulation of gene expression is essential. Dna methylation, the most conserved epigenetic modification, participates in gene expression regulation and transposable element silencing. Honeysuckle(Lonicera japonica) is an important medicinal plant renowned for its colorful and fragrant flowers. Honeysuckle flowers change color from white to gold as a result of carotenoid accumulation during development. However, the role of Dna methylation in flower color changes is not well understood in L. japonica. Here, we performed whole-genome bisulfite sequencing and transcriptome sequencing during flowering development in honeysuckle. The results showed that a decrease in the levels of genome-wide average Dna methylation during flower development and changes in Dna methylation were associated with the expression of demethylase genes. Moreover, many genes involved in carotenoid biosynthesis and degradation, such as Lj PSY1, LjPDS1, LjLCYE, and LjCCD4, have altered expression levels because of hypomethylation, indicating that Dna methylation plays an important role in flower color changes in honeysuckle. Taken together, our data provide epigenetic insights into flower development and color change in honeysuckles.

关键词： Lonicera japonica Dna methylation Epigenetic regulation Gene expression Carotenoid metabolism

Blockage of ATPase-mediated energy supply inducing metabolic disturbances in algal cells under silver nanoparticles stress

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Journal of Environmental Sciences 2023年第9期131卷 141-150页

作者： Ruohua Qu Mi Chen Jingfu Liu Qiting Xie na Liu Fei Ge Department of Environment College of Environment and ResourcesXiangtan UniversityXiangtan 411105China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Adenosine triphosphate(ATP)generation of aquatic organisms is often subject to nanoparticles(NPs)stress,involving extensive reprogramming of gene expression and changes in enzyme activity accompanied by metabolic ***,little is known about the mechanism of energy supply by ATP to regulate the metabolism of aquatic organisms under NPs ***,we selected extensively existing silver nanoparticles(AgNPs)to investigate their implications on ATP generation and relevant metabolic pathways in alga(Chlorella vulgaris).Results showed that ATP content significantly decreased by 94.2%of the control(without AgNPs)in the algal cells at 0.20 mg/L AgNPs,which was mainly attributed to the reduction of chloroplast ATPase activity(81.4%)and the downregulation of ATPase-coding genes atpB and atpH(74.5%-82.8%)in *** dynamics simulations demonstrated that AgNPs competed with the binding sites of substrates adenosine diphosphate and inorganic phosphate by forming a stable complex with ATPase subunit beta,potentially resulting in the reduced binding efficiency of ***,metabolomics analysis proved that the ATP content positively correlated with the content of most differential metabolites such as D-talose,myo-inositol,and *** remarkably inhibited ATPinvolving metabolic pathways,including inositol phosphate metabolism,phosphatidylinositol signaling system,glycerophospholipid metabolism,aminoacyl-tRna biosynthesis,and glutathione *** results could provide a deep understanding of energy supply in regulating metabolic disturbances under NPs stress.

关键词： Adenosine triphosphate Metabolomics Molecular dynamics simulations nanoparticles Algae

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液态有机储氢技术研究现状与展望

化工进展 2024年第4期43卷 1731-1741页

作者：刘若璐汤海波何翡翡罗凤盈王金鸽杨娜李洪伟张锐明先进能源科学与技术广东省实验室佛山分中心(佛山仙湖实验室) 广东佛山528200 广东瀚锐氢能科技有限公司广东佛山528200 广东省武理工氢能产业技术研究院广东佛山528200

随着构建绿色氢能社会愿景的提出,氢能的需求量将会大规模增长,氢能的储运就成为了制约产业规模化发展的瓶颈。液态有机储氢技术在氢能大规模储存和长距离运输上具有成本低、安全性高等传统高压储氢无法比拟的优势,由于这项技术目前仍... 详细信息

随着构建绿色氢能社会愿景的提出,氢能的需求量将会大规模增长,氢能的储运就成为了制约产业规模化发展的瓶颈。液态有机储氢技术在氢能大规模储存和长距离运输上具有成本低、安全性高等传统高压储氢无法比拟的优势,由于这项技术目前仍处于发展初期,国内相关的报道较少。本文综述了芳香烃类和氮杂环芳香烃类等主要的液态有机储氢材料,并对其储氢性能、优势、存在问题及发展现状展开了分析;阐述了液态有机储氢技术中加氢和脱氢过程所涉及的各种金属催化剂的性能。基于目前的研究,对液态有机储氢技术在未来氢能规模化应用方面的发展前景进行了展望,同时指出液态有机储氢技术在诸多氢能应用领域的可行性及其极高的经济价值。但是若要实现大规模应用,则需选择更优的有机储氢材料,开发高选择性、高催化活性及低成本的新型催化剂,进一步优化加氢和脱氢技术。

关键词：液态有机储氢储氢材料芳香烃类氮杂环芳香烃类催化剂加氢脱氢氢

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