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Gas compression and likely triggered star formation in the infrared bubble N107

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Research in Astronomy and Astrophysics 2018年第10期18卷 49-64页

作者： hao Li Jin-Zeng Li Jing-Hua Yuan Ya-Fang huang Zhi-Yuan Ren National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Science University of Chinese Academy of Sciences

The expansion of HII regions can regulate the evolution of their natal clouds and the star for-mation therein. Infrared dust bubbles, which are frequently associated with HII regions, are ideal labora-tories to test whether impulse（s） driven by the expanding bubbles enhances or suppresses star-formation. In this work, we present a comprehensive study of a 20-pc scale infrared bubble N107 to reveal the com- pression of the neutral gas and associated star-forming activities. We obtain column density （NH2） and dust temperature （Tdust） maps via fitting modified blackbodies to multi-band far-infrared Herschel data. The shell structure can be recognized on the column density map. The molecular gas along the rim of N107 fragments into 94 dense clumps at an angular resolution of 18＂. Besides, based on the GLIMPSE point source catalog, we have identified 228 young stellar objects （YSOs） which are categorized into 55 Class I objects, 127 Class II objects and 46 transition disks （TDs）. The 94 clumps and 55 Class I type YSOs are mainly distributed along the shell, which may suggest triggered star formation exists in N107. In addition, analysis of NH2 probability density functions （PDFs） helps us reveal the condition of natal clouds. The two lognormal profiles of PDFs suggest that the surrounding molecular gas has been compressed due to expansion of the bubble. This compression may trigger the star formation process. Moreover, we find the shape of the PDFs changed after removing the background. Taken together, this big bubble seems to compress the surrounding gas and strongly regulate star formation therein.

关键词： ISM HII regions - ISM clouds - stars formation - ISM structure - methods observational

血能铁制剂对哺乳母猪生产性能及生理生化指标的影响

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农业生物技术学报 2025年第1期33卷 116-123页

作者：胡国明黄昌巧周淑棉韦玉衡谢小东胡庭俊胡永浩甘肃农业大学动物医学院广西大学动物科学技术学院贵港市动物疫病预防控制中心

铁作为一种关键的微量元素，对动物的生长具有重大的意义，铁缺乏将会导致发育障碍、繁殖性能不佳、贫血和腹泻等多种不良影响。本研究以产前7 d至产后21 d的哺乳母猪(Sus scrofa domestica)为对象，探讨饲料中添加血能铁制剂对哺乳母... 详细信息

铁作为一种关键的微量元素，对动物的生长具有重大的意义，铁缺乏将会导致发育障碍、繁殖性能不佳、贫血和腹泻等多种不良影响。本研究以产前7 d至产后21 d的哺乳母猪(Sus scrofa domestica)为对象，探讨饲料中添加血能铁制剂对哺乳母猪生产性能、生理生化指标及仔猪相关指标的影响。结果显示，与空白对照组相比，以1 kg/t饲料添加剂量添加血能铁制剂后，连续饲喂28 d能够显著降低母猪助产率、提高断配率，改善母猪产程，增加仔猪初生窝重、仔猪平均体重、断奶窝重，降低仔猪腹泻率、畸形率、死胎率，从而提高母猪生产性能和仔猪生长性能；同时血能铁制剂可以提高第7天哺乳仔猪血清铁和总铁结合力，起到预防仔猪贫血的作用。本研究为兽医临床应用血能铁制剂提高母猪生产性能提供参考和依据。

关键词：血能铁制剂生产性能血液指标

青藏高原东南缘三江并流区植被物候时空变化及其影响因素分析

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嘉应学院学报 2023年第6期41卷 78-87页

作者：谢作轮肖冬梅黄浩鸿蒋娜陈志云刘友存嘉应学院地理科学与旅游学院广东梅州514015

气候变化可以通过影响植被物候来影响生态系统过程,但气候变化过程对区域尺度物候影响尚未达成共识,特别是地形起伏较大、生态系统多样性丰富度较高的区域.基于MODISEVI数据,运用Savitzky-Golay(S-G)滤波、动态阈值、Anusplin插值、Thei... 详细信息

气候变化可以通过影响植被物候来影响生态系统过程,但气候变化过程对区域尺度物候影响尚未达成共识,特别是地形起伏较大、生态系统多样性丰富度较高的区域.基于MODISEVI数据,运用Savitzky-Golay(S-G)滤波、动态阈值、Anusplin插值、Theil-Sen斜率、Mann-Kendall检验和偏相关分析等方法,分析了2001—2019年的三江并流区植被物候的时空分布特征及植被物候与气候要素变化之间的关系.结果表明:(1)三江并流区植被物候的生长季始期(SOS)主要集中在第80—140d,生长季末期(EOS)集中在第290—330d,生长季长度(LOS)介于180—240d之间;整体上东北部高海拔区域生长季始期和末期早于西南河谷区域,河谷区域的生长季长度大于东北部高海拔区域.2001年以来呈现出生长季长度增加、生长季始期提前、生长季末期延迟的趋势.(2)植物生长季始期主要受降水和气温影响,温度对生长季始期的影响也表现为正相关.(3)生长季末期受气温和降水的影响表现出明显的区域差异,东北部高海拔区域主要受到气温的正向影响,西南部河谷区域则主要受降水的负向影响.(4)生长季长度与6—9月份的气温和降水呈正相关关系,其中6月份和9月份的气温为主导因子,7—8月份降水的影响高于气温.

关键词：植被物候气候变化 Anusplin插值偏相关分析三江并流区

Unveiling the promotion of accelerated water dissociation kinetics on the hydrogen evolution catalysis of NiMoO_(4) nanorods

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Journal of Energy Chemistry 2022年第4期31卷 805-813页

作者： Tuzhi Xiong Bowen huang Jingjing Wei Xincheng Yao Ran Xiao Zhixiao Zhu Fang Yang Yongchao huang hao Yang M.-Sadeeq(Jie Tang)Balogun College of Materials Science and Engineering Hunan UniversityChangsha 410082HunanChina Institute of Environmental Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006GuangdongChina Guangxi Key Laboratory of Electrochemical Energy Materials School of Chemistry&Chemical EngineeringGuangxi UniversityNanning 530004GuangxiChina Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy Hunan UniversityChangsha 410082HunanChina

Nickel molybdate(NiMoO_(4))attracts superior hydrogen desorption behavior but noticeably poor for efficiently driving the hydrogen evolution reaction(HER)in alkaline media due to the sluggish water dissociation ***,we successfully accelerate the water dissociation kinetics of NiMoO_(4)for prominent HER catalytic properties via simultaneous in situ interfacial engineering with molybdenum dioxide(MoO_(2))and doping with phosphorus(P).The as-synthesized P-doped NiMoO_(4)/MoO_(2)heterostructure nanorods exhibit outstanding HER performance with an extraordinary low overpotential of-23 m V at a current density of 10 m A cm^(-2),which is highly comparable to the performance of the state-of-art Pt/C coated on nickel foam(NF)*** density functional theory(DFT)analysis reveals the enhanced performance is attributed to the formation of MoO_(2)during the in situ epitaxial growth that substantially reduces the energy barrier of the Volmer pathway,and the introduction of P that provides efficient hydrogen desorption of Ni MoO_(2).This present work creates valuable insight into the utilization of interfacial and doping systems for hydrogen evolution catalysis and beyond.

关键词： NiMoO_(4)/MoO_(2) Water dissociation kinetics Interfacial and doping Density functional theory Hydrogen evolution reaction

Impact of gasoline engine deposits on light duty vehicle emissions： in-use case study in Beijing, China

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Frontiers of Environmental Science & Engineering 2012年第5期6卷 717-724页

作者： Xin YUE Ye WU Xianjiang huang Yao MA Yuan PANG Xiaofeng BAO Jiming hao School of Environment Tsinghua UniversityBeijing 100084China Chinese Research Academy of Environmental Sciences Beijing 100012China

Tailpipe emissions from light-duty gasoline vehicles usually deteriorate over time. The accumulation of engine deposits due to inadequate gasoline detergency is considered to be one of the major causes of such emission deterioration. Six in-use light-duty gasoline vehicles in Beijing were tested to investigate the impact of engine deposits on emissions of hydrocarbons （HC）, carbon monoxide （CO） and nitrogen oxides （NOx）. Emissions under cold start and hot running test conditions from the six light duty vehicles were measured before and after engine deposits were removed. Results show that although individual vehicles reacted differently for each of the pollutants, elimination of engine deposits on average reduced HC emissions under hot running conditions by 29.4%, CO emissions under cold start conditions by 23.0% and CO emissions under hot running conditions by 35.5% （t 〈 0.05 in all cases）. No pollutant emissions increased with statistical significance （t 〈 0.05） after the removal of engine deposits. Variations of emission changes upon removal of engine deposits were observed. Such variations are in line with previous studies, implying that the impact patterns of engine deposits on vehicle emissions may be subject to many influencing factors that are not fully understood and difficult to control under all conditions. A statistical view of the impact of engine deposits on vehicle emissions may be appropriate for evaluation of emissions reductions across a city or a country. It is necessary to maintain sufficient and effective gasoline fuel detergency in practice to keep the engines clean and in tum reduce vehicle emissions.

关键词： engine deposit fuel quality detergency,vehicle emission

Avalanche activity and characteristics of its triggering factors in the western Tianshan Mountains,China

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Journal of Mountain Science 2018年第7期15卷 1397-1411页

作者： hao Jian-sheng huang Fa-rong LIU Yang Amobichukwu Chukwudi AMANAMBU LI Lan-hai State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences No. 818 South Beijing Road Urumqi 830011 China. University of Chinese Academy of sciences Bering 100049 China Yili Station for Watershed Ecosystem Research Chinese Academy of Sciences No. 818 South Beijing Road Urumqi 830011 China. Xinjiang Regional Center of Resources and Environmental Science Instrument Chinese Academy of Sciences Urumqi 830011 China CAS Research Center for Ecology and Environment in Central Asia No. 818 South Beijing Road Urumqi Xinjiang 830011 China

Snow avalanche is a serious threat to the safety of roads in alpine mountains. In the western Tianshan Mountains, large scale avalanches occur every year and affect road safety. There is an urgent need to identify the characteristics of triggering factors for avalanche activity in this region to improve road safety and the management of natural hazards. Based on the observation of avalanche activity along the national road G218 in the western Tianshan Mountains, avalanche event data in combination with meteorological, snowpack and earthquake data were collected and analyzed. The snow climate of the mountain range was examined using a recently developed snow climate classification scheme, and triggering conditions of snow avalanche in different snow climate regions were compared. The results show that snowfall is the most common triggering factor for a natural avalanche and there is high probability of avalanche release with snowfall exceeding 20.4 mm during a snowfall period. Consecutive rise in temperature within three days and daily mean temperature reaching 0.5℃ in the following day imply a high probability of temperaturerise-triggered avalanche release. Earthquakes have a significant impact on the formation of large size avalanches in the area. For the period 2011-2017, five cases were identified as a consequence of earthquake with magnitudes of 3.3≤M_L≤5.1 and source-to-site distances of 19~139 km. The Tianshan Mountains are characterized by a continental snow climate with lower snow density, lower snow shear strength and high proportion depth hoar, which explains that both the snowfall and temperature for triggering avalanche release in the continental snow climate of the Tianshan Mountains are lower than that in maritime snow climate and transitional snow climate regions. The findings help forecast avalanche release for mitigating avalanche disaster and assessing the risk of avalanche disaster.

关键词： Snow avalanche Snow properties Snow climate Triggering conditions Risk management

Reductive Amination of Carbonyl Compounds with Ammonia and Hydrogenation of Nitriles to Primary Amines with Heterogeneous Cobalt Catalysts

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Chemical Research in Chinese Universities 2019年第3期35卷 457-462页

作者： LIU Junmei GUO Wanwan SUN hao LI Ruyue FENG Zhipeng ZHOU Xuyang huang Jun State Key Laboratory ofMaterials-ori ented Chemical Engineering College of Chemical Engineering Nanjing Tech UniversityNanjing 210009P.R.China

Reductive amination of aldehydes/ketones with aqueous NH3 and hydrogenation of nitriles to primary amines with Co catalysts were reported. Co@NC-700 exhibited remarkable activity and high selectivity for the reductive amination of aldehydes/ketones with aqueous NH3 and the hydrogenation of nitriles to primary amines. Several primary amines can be obtained with good to excellent yields via the reductive amination of aldehydes/ketones and the hydrogenation of nitriles. The nitrogen-doped carbon(C)-supported Co@NC-700 metal catalyst was prepared via the pyrolysis of bioMOF Co/adenine in activated C. Co@NC-700 can be reused five times without evident loss of activity.

关键词： Primary amine Cobalt Reductive amination Aldehyde Hydrogenation Nitrile

Crustal P-wave velocity structure of the Longmenshan region and its tectonic implications for the 2008 Wenchuan earthquake

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Science China Earth Sciences 2011年第9期54卷 1386-1393页

作者： LI ZhaWei XU Yi huang RunQiu hao TianYao XU Ya LIU JingSong LIU JianHua Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

The P-wave velocity structure of the crust in the Longmenshan region has been imaged by seismic travel time tomography us ing local and regional first P-wave arrivals recorded from 2000 to 2008. The tomographic model provides a way to analyze the deep tectonics of the Longmenshan fault belt and the tectonic implications for the 2008 Ms8.0 Wenchuan earthquake. The P-wave velocity images indicate that the initial rupture site and focal depth of the Wenchuan earthquake, together with the di rection of rupture propagation, closely relate to the crustal structure of the Longmenshan region. The Pengguan massif to the west of the Longmenshan fault belt is characterized by high velocity anomalies, suggesting that the crust has a strong strain strength that can accumulate large stresses over a long period. The Ms8.0 Wenchuan earthquake is located at the southwestern end of the Pengguan massif and the western edge of the Sichuan Basin. The collision between the Pengguan massif and the Sichuan Basin becomes the primary reason for the occurrence of the Ms8.0 Wenchuan earthquake. To the north of Wenchuan, the occurrence and propagation of rupture benefit from low velocity anomalies along the Longmenshan fault belt; whereas to the south of Wenchuan, the brittle rupture can occur with more difficulty in relatively weak crust with low velocities. This may be one of the reasons for the absence of aftershocks to the south of Wenchuan, and the rupture induced by the Ms8.0 Wenchuan earthquake propagating from the north to the south along the Longmenshan fault belt. The deep geodynamics of the Ms8.0 Wenchuan earthquake may occur due to the discrepancy of crustal structures on the two sides of the Longmenshan fault belt. Ductile deformation and crustal flow can easily occur in the weak middle-lower crust beneath the Songpan-Garze orogenic belt. The eastward movement of the Tibetan Plateau is obstructed by the rigid lithosphere of the Sichuan Basin, and then the thick ening of the middle-

关键词： Longmenshan orogenic belt Wenchuan earthquake P-wave velocity crustal structure travel time tomography

Dead lithium formation in lithium metal batteries:A phase field model

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Journal of Energy Chemistry 2022年第8期31卷 29-35,I0002页

作者： Rui Zhang Xin Shen Yu-Tong Zhang Xia-Lin Zhong hao-Tian Ju Tian-Xiao huang Xiang Chen Jun-Dong Zhang Jia-Qi huang Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Lithium metal batteries are the most promising choices for next-generation high-energy–density batteries. However, there is little mechanism understanding on lithium dendrite growth during lithium plating and the dead lithium(the main component of inactive lithium) formation during lithium stripping. This work proposed a phase field model to describe the lithium stripping process with dead lithium *** coupling of galvanostatic conditions enables the phase field method to accurately match experimental results. The factors influencing the dead lithium formation on the increasing discharge polarization are revealed. Besides, the simulation of the battery polarization curve, the capacity loss peak, and the Coulomb efficiency is realized. This contribution affords an insightful understanding on dead lithium formation with phase field methods, which can contribute general principles on rational design of lithium metal batteries.

关键词： Lithium metal batteries Lithium metal anodes Lithium dendrites Dead lithium Lithium stripping Phase field methods Finite element methods