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Combined effects of climate and land-use changes on the alpha and beta functional diversities of terrestrial mammals in China

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Science China Life Sciences 2024年第10期67卷 2224-2233页

作者： Chao Zhang Yumei Li Wei Wang Zexuan Gao Hanqing Liu yonggang Nie Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of Sciences College of Life Sciences Hebei University University of Chinese Academy of Sciences

Climate and land-use changes are predicted to impact biodiversity, threatening ecosystem services and functions. However, their combined effects on the functional diversity of mammals at the regional scale remain unclear, especially at the beta level. Here, we use projected climate and land-use changes in China to investigate their potential effects on the alpha and beta functional diversities of terrestrial mammals under low-and high-emission scenarios. In the current projection, we showed strong positive spatial correlations between functional richness and species richness. Functional evenness(FEve), functional specialization(FSpe), and functional originality(FOri)decreased with species richness, and functional divergence(FDiv) increased first and then plateaued. Functional beta diversity was dominated by its nestedness component, in contrast to the taxonomic facet. Potential changes in species richness are more strongly influenced by land-use change under the low-emission scenario, while under the high-emission scenario, they are more strongly influenced by climate change. Changes in functional richness(FRic) were inconsistent with those in species richness, with a magnitude of decreases greater than predicted from species richness. Moreover, mammal assemblages showed potential functional differentiation(FD) across the country, and the trends exceeded those towards taxonomic differentiation(TD). Our findings help us understand the processes underlying biodiversity responses to global changes on multiple facets and provide new insight for conservation plans.

关键词： climate change land-use change functional diversity terrestrial mammals biodiversity conservation

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乙烯基笼型倍半硅氧烷/聚丙烯纳米复合材料热降解动力学

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高分子材料科学与工程 2011年第6期27卷 106-109页

作者：曹新鑫高俊刚杜永刚河北大学化学与环境科学学院河北保定071002 河南理工大学材料学院河南焦作454000

用热重分析(TGA)法研究了乙烯基笼型倍半硅氧烷(V-POSS)/聚丙烯纳米复合材料的热降解动力学。采用Kim-Park,Flynn-Wall-Ozawa和Friedman三种方法计算了共混物的降解反应活化能,结果说明,当V-POSS加入质量分数分别为4%、8%、12%和16%、... 详细信息

用热重分析(TGA)法研究了乙烯基笼型倍半硅氧烷(V-POSS)/聚丙烯纳米复合材料的热降解动力学。采用Kim-Park,Flynn-Wall-Ozawa和Friedman三种方法计算了共混物的降解反应活化能,结果说明,当V-POSS加入质量分数分别为4%、8%、12%和16%、升温速率为5℃/min时材料热降解起始温度分别提高了27.1℃、29.3℃、52.6℃和66.9℃,热降解反应活化能E_a提高了10 kJ/mol～50 kJ/mol,反应级数n也随V-POSS加入量增多有所提高,材料热稳定性得到了改善。

关键词：笼型聚倍半硅氧烷聚丙烯热重分析降解动力学

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Safety and efficacy of Yupingfeng granules in children with recurrent respiratory tract infection:A randomized clinical trial

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Pediatric Investigation 2022年第2期6卷 75-84页

作者： Baoping Xu Xinmin Li Siyuan Hu Yixiao Bao Fengmei Chen Zhimin Chen yonggang du Enmei Liu Yufeng Liu Qinghui Mou Baoling Su Bo Wang Jianwen Xu Guiping Xu Qiaozhi Yang Liwei Gao Xiaohui Liu Lei Li Rong Ma Kunling Shen China National Clinical Research Center of Respiratory Diseases Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina The First Teaching Hospital of Tianjin University of Traditional Chinese Medicine TianjinChina Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine ShanghaiChina Guangdong Women and Children Hospital and Health Institute GuangzhouGuangdongChina Children’s Hospital of Zhejiang University School of Medicine ZhejiangChina Changzhi People’s Hospital ChangzhiShanxiChina Children’s Hospital of Chongqing Medical University ChongqingChina The Fourth Affiliated Hospital of Liaoning University of Traditional Chinese Medicine ShenyangLiaoningChina Qilu Children’s Hospital of Shandong University JinanShandongChina Heji Hospital Affiliated to Changzhi Medical College ChangzhiShanxiChina The Third Affiliated Hospital of Xinxiang Medical College XinxiangHenanChina Huizhou Traditional Chinese Medicine Hospital GuangdongChina Liaocheng People’s Hospital ShandongChina Beijing Children’s Hospital Capital Medical UniversityNational Center for Children’s HealthBeijingChina Drug Research and Evaluation Technology Center Chinese Assocaiation of Traditional Chinese MedicineBeijingChina

Importance:Recurrent respiratory tract infection(RRTI)is common in *** RRTI treatment will lead to asthma and other diseases,thereby seriously affecting the growth and physical health of *** function modulation can prevent and alleviate childhood ***(YPF),a patented traditional Chinese medicine(TCM),has immunomodulatory effects and is widely used in China to treat children with ***:To evaluate the safety and efficacy of YPF monotherapy in treating children with ***:This multicenter,randomized,double-blind,double-simulation,noninferiority clinical trial was conducted from January 2015 to August 2017,with an 8-week treatment period and 52-week follow-up after the drug *** aged 2–6 years with RRTI meeting the inclusion and exclusion criteria were enrolled in 13 hospitals in China and divided randomly into three groups(2:2:1 ratio)to receive YPF,pidotimod,or *** primary outcome was the proportion of RRTI returning to normal standard level during the *** secondary outcomes were reduction in the number of RRTI recurrences,effect on clinical symptoms(in accord with TCM practice),effect per symptom,and *** trial was registered at the Chinese Clinical Trials Registry(***)under the unique identifier ***:Three hundred and fifty-one children were enrolled and randomly assigned to 3 groups;124,125,and 61 children in the YPF,pidotimod,and placebo groups,respectively,had completed the *** the follow-up,the proportion of RRTI returning to normal standard level was 73.13%,67.15%,and 38.81%with YPF,pidotimod,and placebo,respectively(P<0.0001).The proportion of cases who returned to normal standard level in the YPF group was 34.32%higher than that in the placebo *** safety profile did not significantly differ among the ***:YPF granules were noninferior to the active control drug pidotimod oral solution for the tr

关键词： Pidotimod Recurrent childhood respiratory tract infection Traditional Chinese medicine Yupingfeng

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Extraction of weak values in the process of retrieving quantum entanglement state

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Optoelectronics Letters 2024年第10期20卷 636-640页

作者： du Shaojiang FENG Hairan ZHANG Lu YANG Lianwu PENG yonggang School of Physical Science and Intelligent Engineering Jining University School of Physics Shandong University

A reversible operation protocol is provided for a weak-measured quantum entanglement state. The evolution of weak values is studied under different parameter conditions. The weak values can be extracted from the entanglement state and the weak-measured quantum entanglement state can be revived to its initial state theoretically by weak measurement and reversibility operation respectively. We demonstrate the reversible operation protocol by taking Bell's state as an example. The negativity is used to analyze the initial state, the weak-measured state and the reversed state in order to describe the evolution of quantum entanglement degree. Weak values are detected from the quantum entanglement state by weak measurement and the degree of the weak-measured quantum entanglement state can be revived to its initial state through reversible operation. The information of quantum entanglement state would be extracted from weak values detected in the process of the scheme.

关键词： A

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Halogenated Thienoacene Derivatives with Improved Emission Properties

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Chemical Research in Chinese Universities 2024年第4期40卷 699-703页

作者： ZHANG Jingmei MENG Zhihao ZHEN yonggang HE Ping YU Panpan HU Wenping Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic CompositesBeijing University of Chemical TechnologyBeijing100029P.R.China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan430074P.R.China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian116024P.R.China Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province China West Normal UniversityNanchong637000P.R.China Key Laboratory of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education Jiangxi Normal UniversityNanchang330022P.R.China MOE Key Laboratory of Organic Integrated Circuits&Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of SciencesTianjin UniversityTianjin300072P.R.China

Thienoacenes is one of most important groups of semiconducting materials due to the high stability and superior ***,there are scarce studies on the emission properties of thienoacenes to ***,we synthesized fluorinated and chlorinated dibenzo[d,d’]thieno[3,2-b;4,5-b’]dithiophenes(DBTDTs)derivatives F6-DBTDT and Cl6-DBTDT by sulfoxide cyclization,significantly lowering the energy levels relative to the parent compound *** to single crystal structure analysis,F6-DBTDT molecules adopt one-dimensional slipped stacking with closeπ-πinteractions of 3.43Å(1Å=0.1 nm),which is different from the parent compound DBTDT with herringbone stacking ***,the halogenated DBTDT derivatives exhibit enhanced emission properties both in solution and in the solid state,opening up possiblities to improve photoluminescence of thienoacences by halogenation.

关键词： Thienoacene Halogenation Photoluminescence Aggregation structure

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Extrusion 3D printing of carbon nanotube-assembled carbon aerogel nanocomposites with high electrical conductivity

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Nano Materials Science 2024年第3期6卷 312-319页

作者： Lukai Wang Jing Men Junzong Feng yonggang Jiang Liangjun Li Yijie Hu Jian Feng Science and Technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense Technology109 De Ya RdChangshaHunan410073PR China

Carbon nanotubes(CNTs)with high aspect ratio and excellent electrical conduction offer huge functional improvements for current carbon ***,there remains a major challenge for achieving the on-demand shaping of carbon aerogels with tailored micro-nano structural textures and geometric ***,a facile extrusion 3D printing strategy has been proposed for fabricating CNT-assembled carbon(CNT/C)aerogel nanocomposites through the extrusion printing of pseudoplastic carbomer-based inks,in which the stable dispersion of CNT nanofibers has been achieved relying on the high viscosity of carbomer *** extrusion printing,the chemical solidification through polymerizing RF sols enables 3D-printed aerogel nanocomposites to display high shape fidelity in macroscopic *** from the micro-nano scale assembly of CNT nanofiber networks and carbon nanoparticle networks in composite phases,3D-printed CNT/C aerogels exhibit enhanced mechanical strength(fracture strength,0.79 MPa)and typical porous structure characteristics,including low density(0.220 g cm^(-3)),high surface area(298.4 m^(2)g^(-1)),and concentrated pore diameter distribution(~32.8nm).More importantly,CNT nanofibers provide an efficient electron transport pathway,imparting 3D-printed CNT/C aerogel composites with a high electrical conductivity of 1.49 S cm^(-1).Our work would offer feasible guidelines for the design and fabrication of shape-dominated functional materials by additive manufacturing.

关键词： Carbon aerogel Extrusion 3D printing Carbon nanotube Electrical conductivity Rheology

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Tuning exciton dynamics by the dielectric confinement effect in quasi-two-dimensional perovskites

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Photonics Research 2024年第3期12卷 563-570页

作者： MINGHUAN CUI CHAOCHAO QIN YUANZHI JIANG SHICHEN ZHANG CHANGJIU SUN MINGJIAN YUAN yonggang YANG YUFANG LIU Henan Key Laboratory of Infrared Materials&Spectrum Measures and Applications Henan Normal UniversityXinxiang 453007China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China Institute of Physics Henan Academy of SciencesZhengzhou 450046China

The dielectric confinement effect plays an essential role in optoelectronic *** studies on the relationship between the dielectric confinement and the photoelectric properties are ***,three organic spacers with different dielectric constants are employed to tune the exciton dynamics of quasi-two-dimensional(quasi-2D)Ruddlesden–Popper perovskite *** transient absorption spectroscopy reveals that the small dielectric constant ligand enables a weak dynamic disorder and a large modulation depth of the coherent phonons,resulting in a more complete energy transfer and the inhibition of a trap-mediated nonradiative ***,the increase in the bulk-ligand dielectric constant reduces the corresponding exciton binding energy and then suppresses the Auger recombination,which is beneficial for high-luminance lightemitting *** work emphasizes the importance of dielectric confinement for regulating the exciton dynamics of layered perovskites.

关键词： dielectric perovskite quasi

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综采工作面巡检机器人柔性轨道设计与运动学仿真

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煤炭科学技术 2022年第12期50卷 240-246页

作者：张旭辉杜永刚霍鑫健王川伟西安科技大学机械工程学院陕西西安710054 陕西省矿山机电装备智能监测重点实验室陕西西安710054

煤矿井下综采工作面空间狭小、设备动作频繁,位置关系复杂等问题,导致常规巡检机器人难以直接在工作面运行,自动化监测难度大。根据工况需求,结合环境及设备群动作特点,提出工作面巡检轨道设计要求,采用模块化设计、仿真模拟和样机试验... 详细信息

煤矿井下综采工作面空间狭小、设备动作频繁,位置关系复杂等问题,导致常规巡检机器人难以直接在工作面运行,自动化监测难度大。根据工况需求,结合环境及设备群动作特点,提出工作面巡检轨道设计要求,采用模块化设计、仿真模拟和样机试验的方法,设计一种新型跨座式巡检机器人柔性轨道,实现在工作面环境的安装调节及当安装设备发生动作变形时轨道自身的自适应补偿。首先设计了巡检机器人柔性轨道的机械结构并确定安装运行方式。其次,以轨道跨接在刮板输送机线缆槽一侧为例,分析刮板输送机在平直、弯曲和起伏3种工况下的弯曲和俯仰变形量,并对柔性轨道进行运动学仿真。在3种工况下,该轨道可随工作面设备完成水平弯曲0~5.4°、竖直倾斜0~6°、伸缩变形0~120 mm,满足实际工况要求。巡检机器人通过柔性轨道时,其主运动方向始终保持匀速直线运动,水平或竖直方向在柔性过度段存在波动,波动幅值均在安全允许范围内。最后搭建柔性轨道物理样机及工作面试验平台,对工作面巡检机器人柔性轨道进行性能验证。结果表明:新型跨座式巡检机器人柔性轨道结构设计合理,可以适应工作面巡检的不同工况,对实现煤矿井下综采工作面机器人巡检具有重要意义。

关键词：综采工作面柔性轨道巡检机器人刮板输送机运动学仿真

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Atomization characteristics of pyrolysis oil derived from waste tires

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Waste Disposal and Sustainable Energy 2024年第1期6卷 39-52页

作者： Hong Feng Zhitong Yin Qin Hong Yiming Hu Lintao Liu Jun Wang Qunxing Huang yonggang Zhou ZJMI Environmental Energy Co. LtdHangzhou310003China Tongxiang Taiaisi Environmental Protection Energy Co. Ltd.Jiaxing314500China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou310027China Key Laboratory of Clean Energy and Carbon Neutrality of Zhejiang Province Jiaxing Research InstituteZhejiang UniversityJiaxing314031China

The atomization characteristics play a key role in the highly efficient combustion of pyrolysis oil derived from waste *** this study,the fuel properties of tire pyrolysis oil(TPO)were initially studied,and then a high-speed camera and a phase Doppler particle analyzer were employed to characterize the atomization feature of *** influence of pressure and nozzle orifice diameter on atomization characteristics such as spray angle,droplet velocity,and droplet size distribution was *** results showed that TPO had a high calorific value of about 43.6 MJ/kg and a low viscosity of 3.84×10^(–6)m^(2)/s at 40℃,which made it have the potential to be used as an alternative *** pressure expanded the spray angle and extended the spray in both the axial and radial *** increasing pressure,spray angle and droplet velocity raised,and the increase in crushing effect of air reduced the Sauter mean diameter(SMD)of the *** obtain proper atomization quality for combustion,the pressure is expected to be higher than 1.25 *** increasing nozzle orifice diameter,droplet velocity increased,and the SMD of the droplets increased as well due to weakened crushing effect of the ***,the pressure must be increased to maintain the atomization quality when using a nozzle with a larger *** to the lower viscosity,the velocity and particle size distribution of TPO droplets after atomization were smaller than those of diesel *** extremely small carbon black contained in TPO also contributed to the breaking of droplets and played a certain role in the size reduction of the oil droplets,but it may cause the risk of nozzle *** summary,TPO showed great atomization characteristics for alternative fuel applications.

关键词： Pyrolysis oil Atomization characteristics Spray angle Droplet velocity Droplet size distribution

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一种多片舵同步展开模拟负载技术的可行性研究

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机床与液压 2021年第17期49卷 128-131页

作者：杜永刚于锟锟兰州空间技术物理研究所甘肃兰州730000

火工展开技术广泛应用在导弹折叠翼和折叠舵领域中,模拟负载技术是其测试过程中的关键技术之一。利用多组气缸实现多组模拟负载是一种较为新颖的方法,介绍了这种多组气缸驱动的模拟负载器的原理、组成等。在气缸加载的数学模型中加入气... 详细信息

火工展开技术广泛应用在导弹折叠翼和折叠舵领域中,模拟负载技术是其测试过程中的关键技术之一。利用多组气缸实现多组模拟负载是一种较为新颖的方法,介绍了这种多组气缸驱动的模拟负载器的原理、组成等。在气缸加载的数学模型中加入气缸质量、摆动影响因素,应用MATLAB进行编程和仿真计算。结果表明:该方法可以实现多片舵的模拟负载的加载,在模拟出大负载的同时,兼顾了机械加载快速响应的优点。该模拟负载器结构简单、成本低廉,具有很好的应用前景和经济效益。

关键词：模拟负载多片舵展开可行性研究

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