检索结果-南通市图书馆

Unraveling the morphological evolution mechanism of solid sulfur species in lithium-sulfur batteries with operando light microscopy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2022年第10期31卷 460-468,I0012页

作者： Jingqiang Zheng Chaohong Guan Huangxu Li yangyang xie Junxian Hu Kai Zhang Bo Hong Yanqing Lai Jie Li Zhian Zhang School of Metallurgy and Environment Hunan Province Key Laboratory of Nonferrous Value-Added MetallurgyCentral South UniversityChangsha 410083HunanChina University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai 200240China Department of Chemistry City University of Hong KongKowloonHong Kong 999077China

Solid-liquid phase conversion between various sulfur species in lithium-sulfur(Li-S)batteries is a fundamental reaction of the sulfur cathode.Disclosing the morphological evolution of solid sulfur species upon cycling is of great significance to achieving high energy densities.However,an in-depth investigation of the internal reaction is still lacking.In this work,the evolution process of solid sulfur species on carbon substrates is systematically studied by using an operando light microscope combined with in situ electrochemical impedance spectra technology.The observation of phenomena such as bulk solid sulfur species can form and dissolve independently of the conductive substrates and the transformation of supercooled liquid sulfur to crystalline sulfur.Based on the phenomena mentioned above,a possible mechanism was proposed in which the dissolution reaction of solid sulfur species is a spatially free reaction that involves isotropic physical dissolution,diffusion of molecules,and finally the electrochemical reaction.Correspondingly,the formation of solid sulfur species tends to be a form of crystallization in a saturated solution rather than electrodeposition,as is commonly believed.Our findings offer new insights into the reaction of sulfur cathodes and provide new opportunities to design advanced sulfur cathodes for Li-S batteries.

关键词： Lithium-sulfur batteries Morphological evolution Supercooled liquid sulfur Operando light microscopy Liquid sulfur droplets

在线全文

学校读者我要写书评

暂无评论

水下爆炸多气泡耦合形态及载荷分布特性

兵器装备工程学报 2024年第6期45卷 10-18页

作者：谢洋洋孙岩青岛哈尔滨工程大学创新发展中心山东青岛266000

多爆源水下爆炸产生的气泡在相互耦合作用后,其形态演化以及脉动载荷分布特性与单个气泡相比存在着显著差异。基于超算工作站,由LS-DYNA有限元软件,建立了自由场中爆源中心距离为一个气泡最大半径R的三气泡及四气泡水平阵列三维模型,使... 详细信息

多爆源水下爆炸产生的气泡在相互耦合作用后,其形态演化以及脉动载荷分布特性与单个气泡相比存在着显著差异。基于超算工作站,由LS-DYNA有限元软件,建立了自由场中爆源中心距离为一个气泡最大半径R的三气泡及四气泡水平阵列三维模型,使用ALE算法计算分析了多气泡融合发展形态演变过程和融合气泡空间载荷分布情况。研究表明,多气泡融合后射流发生在气泡水平两端;融合气泡局部坍塌的不一致造成了三气泡融合气泡上方坍塌载荷较四气泡融合气泡坍塌载荷大,但是三气泡融合气泡总冲量始终小于四气泡融合气泡;对比单气泡,多气泡脉动周期增大,三气泡、四气泡第1次脉动周期与单气泡比值分别为137%、147%;多气泡脉动载荷显著增强,三气泡、四气泡中心上方距离R处脉动载荷峰值与单气泡同样位置处的脉动载荷峰值比值分别为400%、263%。

关键词：水下爆炸融合气泡气泡脉动载荷分布特性数值仿真

Nitrogen doping and graphitization tuning coupled hard carbon for superior potassium-ion storage

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2020年第10期29卷 327-334页

作者： Junxian Hu yangyang xie Meng Yin Zhian Zhang School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina

Hard carbon material is one of the most promising anode materials for potassium ion batteries(PIBs)due to its distinct disordered and non-expandable framework.However,the intrinsically disordered microarchitecture of hard carbon results in low electric conductivity and poor rate capability.Herein,nitrogendoped and partially graphitized hard carbons(NGHCs)derived from commercial coordination compound precursor-ethylenediaminetetraacetic acid(EDTA)disodium cobalt salt hydrate are designed and prepared as high-performance PIBs anode materials.By means of a facile annealing method,nitrogen elements and graphitic domains can be controllably introduced to NGHCs.The resulting NGHCs show structural merits of mesoporous construction,nitrogen doping and homogeneous graphitic domains,which ensures fast kinetics and electron transportation.Applying in anode for PIBs,NGHCs exhibit robust rate capability with high reversible capacity of 298.8 m Ah g^-1 at 50 m A g^-1,and stable cycle stability of 137.6 mAh g^-1 at 500 m A g^-1 after 1000 cycles.Moreover,the ex situ Raman spectra reveal a mixture"adsorption-intercalation mechanism"for potassium storage of NGHCs.More importantly,full PIBs by pairing with perylenetetracarboxylic dianhydride(PTCDA)cathode demonstrate the promising potential of practical application.In terms of commercial precursor,facile synthesis and long cycle lifespan,NGHCs represent a brilliant prospect for practical large-scale applications.

关键词： Hard carbon Nitrogen doping Graphitic domains Potassium ion batteries Adsorption-intercalation mechanism

Spatiotemporal variations of PM_(2.5) and PM_(10) concentrations between31 Chinese cities and their relationships with SO_2,NO_2,CO and O_3

在线全文

学校读者我要写书评

暂无评论

Particuology 2015年第3期13卷 141-149页

作者： yangyang xie Bin Zhao Lin Zhang Rong Luo Department of Building Science School of ArchitectureTsinghua University Department of Electronic Engineering Tsinghua University

The variations of mass concentrations of PM2.5, PMl0, SO2, NO2, CO, and 03 in 31 Chinese provincial capital cities were analyzed based on data from 286 monitoring sites obtained between March 22, 2013 and March 31,2014. By comparing the pollutant concentrations over this length of time, the characteristics of the monthly variations of mass concentrations of air pollutants were determined. We used the Pearson correlation coefficient to establish the relationship between PM2.5, PM10, and the gas pollutants. The results revealed significant differences in the concentration levels of air pollutants and in the variations between the different cities. The Pearson correlation coefficients between PMs and NO2 and SO2 were either high or moderate （PM2.s with NO2： r = 0.256-0.688, mean r = 0,498：PM10 with NO2： r = 0.169-0.713, mean r=0.493; PM2.5 with SO2： r=0.232-0.693, mean r=0.449; PM10 with SO2： r=0.131-0.669, mean r = 0.403）. The correlation between PMs and CO was diverse （PM2.5： r = 0.156-0.721, mean r = 0.437; PMl0： r= 0.06-0.67, mean r= 0.380）. The correlation between PMs and 03 was either weak or uncorrelated （PM2.s： r= -0,35 to 0.089, mean r= -0.164; PM10： r= -0.279 to 0.078, mean r= -0.127）, except in Haikou （PM2.5： r=0.500; PM10： r=0,509）.

关键词： PM2.5PM40 Atmospheric air pollutantIndoor environmentOutdoor environment

Unveiling nanoplates-assembled Bi2MoO6 microsphere as a novel anode material for high performance potassium-ion batteries

在线全文

学校读者我要写书评

暂无评论

Nano Research 2020年第10期13卷 2650-2657页

作者： Junxian Hu yangyang xie Jingqiang Zheng Yanqing Lai Zhian Zhang School of Metallurgy and Environment Central South Universityy Changsha 410083China

Bismuth (Bi)-based electrode has aroused tremendous interest in potassium-ion batteries (PIBs) on account of its low cost, high electronic conductivity, low charge voltage and high theoretical capacity. However, the rapid capacity fading and poor lifespan induced by the normalized volume expansion (up to ~ 406%) and serious aggregation of Bi during cycling process hinder its application. Herein, bismuth molybdate (Bi2MoO6) microsphere assembled by 2D nanoplate units is successfully prepared by a facile solvothermal method and demonstrated as a promising anode for PIBs. The unique microsphere structure and the self-generated potassium molybdate (K-Mo-O species) during the electrochemical reactions can effectively suppress mechanical fracture of Bi-based anode originated from the volume variation during charge/discharge of the battery. As a result, the Bi2MoO6 microsphere without hybridizing with any other conductive carbon matrix shows superior electrochemical performance, which delivers a high reversible capacity of 121.7 mAh·g^−1 at 100 mA·g^−1 over 600 cycles. In addition, the assembled perylenetetracarboxylic dianhydride (PTCDA)//Bi2MoO6 full-cell coupled with PTCDA cathode demonstrates the potential application of Bi2MoO6 microsphere. Most importantly, the phase evolution of Bi2MoO6 microsphere during potassiation/depotassiation process is successfully deciphered by ex situ X-ray diffraction (XRD), X-ray photoemission spectroscopy (XPS), and transmission electron microscopy (TEM) technologies, which reveals a combination mechanism of conversion reaction and alloying/dealloying reaction for Bi2MoO6 anode. Our findings not only open a new way to enhance the performance of Bi-based anode in PIBs, but also provide useful implications to other alloy-type anodes for secondary alkali-metal ion batteries.

关键词： Bi2MoO6 microsphere potassium ion batteries mechanism anode

Six-day measurement of size-resolved indoor fluorescent bioaerosols of outdoor origin in an office

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2017年第2期15卷 161-169页

作者： yangyang xie Oscar A. Fajardo Weizhuo Yan Bin Zhao Jingkun Jiang Department of Building Science School of Architecture Tsinghua University Beijing 100084 China Beijing Key Laboratory oflndoorAir Quality Evaluation and Control Tsinghua University Beijing 100084 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084 China

Indoor airborne bioaerosols of outdoor origin play an important role in determining the exposure of humans to bioaerosols because people spend most of their time indoors. However, there are few studies focusing on indoor bioaerosols originating from outdoors. In this study, indoor versus outdoor size-resolved concentrations and particle asymmetry factors of airborne fluorescent bioaerosols in an office room were measured continuously for 6 days （144 h） using a fluorescent bioaerosol detector. The windows and door of this room were closed to ensure that there was only air infiltration; moreover, any human activities were ceased during sampling to inhibit effects of indoor sources. We focused on fine particles, since few coarse particles enter indoor environments, when windows and doors are closed. Both indoor and outdoor fluorescent bioaerosol size distributions were fit with two-mode lognormal distributions （indoor R2 = 0.935, outdoor R2 = 0.938）. Asymmetry factor distributions were also fit with lognormal distributions （indoor R2 = 0.992, outdoor R2 = 0.992）. Correlations between indoor and outdoor fluorescent bioaerosol concentrations show significant concentration-attenuation and a time lag during the study period. A two-parameter, semi-empirical model was used to predict concentrations of indoor fluorescent bioaerosols of outdoor origin. The measured and predicted concentrations had a linear relationship for the studied size fractions, with an R2 for all size fractions of larger than 0.83.

关键词： Fluorescent bioaerosols Indoor air Outdoor air Waveband integrated bioaerosol sensor（WIBS）Particle size distributions Concentrations

Optimal structure of joint inventory-pricing management with dual suppliers and different lead times

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Management Science and Engineering 2021年第1期6卷 1-24页

作者： Xiaoyi Feng yangyang xie Shouyang Wang Houmin Yan Department of Risk Strategy The Hongkong and Shanghai Banking Corporation LimitedHong KongChina International Institute of Finance School of ManagementUniversity of Science and Technology of ChinaHefeiAnhui230026China University of the Chinese Academy of Sciences Beijing100049China Department of Management Sciences College of BusinessCity University of Hong KongHong KongChina

We consider a joint inventory-pricing control problem in a single-product,periodic-review,dual-supplier inventory system.The two suppliers have different lead times.One expedited supplier offers instantaneous replenishment,and one regular supplier requires an L-period lead time for delivery.The supply quantity is stochastic and the demand is price-dependent.For the expedited inventory replenishment,we characterize the optimal policy as a state-dependent almost-threshold policy by extending the stochastically linear in mid-point to a multidimensional setting.To investigate the optimal regular inventory replenishment and pricing policy,we propose the notions of partially stochastic translation(PST)and increasing partially stochastic translation(IPST),which help in obtaining the antimultimodularity preservation in dynamic programming problems.We provide properties,sufficient conditions,and examples for PST and IPST functions.By applying PST and IPST,we obtain the antimultimodularity of the profit functions.The antimultimodular profit functions ensure that the optimal regular ordering quantity and the optimal price are monotone in the current inventory level and outstanding order quantities.Moreover,we reveal that as the time interval increases,the effects of previous outstanding orders on the optimal regular ordering and pricing decisions are decreasing and increasing,respectively.PST and IPST also enable us to further characterize the optimal expedited ordering quantity as decreasing in the inventory level.However,the optimal expedited ordering quantity can be non-monotone with respect to the outstanding order quantities,as shown in the example.

关键词： Inventory-pricing control Dual supply Lead time Antimultimodularity

Ultra-stable K metal anode enabled by oxygen-rich carbon cloth

在线全文

学校读者我要写书评

暂无评论

Nano Research 2020年第11期13卷 3137-3141页

作者： yangyang xie Junxian Hu Zexun Han Hailin Fan Jingyu Xu Yanqing Lai Zhian Zhang School of Metallurgy and Environment Central South UniversityChangsha410083China Contemporary Amperex Technology Co. Ltd.Ningde352100China

The K metal batteries are emerged as promising alternatives beyond commercialized Li-ion batteries.However,suppressing uncontrolled dendrite is crucial to the accomplishment of K metal batteries.Herein,an oxygen-rich treated carbon cloth(TCC)has been designed as the K plating host to guide K homogeneous nucleation and suppress the dendrite growth.Both density function theory calculations and experimental results demonstrate that abundant oxygen functional groups as K-philic sites on TCC can guide K nucleation and deposition homogeneously.As a result,the TCC electrode exhibits an ultra-long-life over 800 cycles at high current density of 3.0 mA·cm^(−2)for 3.0 mA·h·cm^(−2).Furthermore,the symmetrical cells can run stably for 2,000 h with low over-potential less than 20 mV at 1.0 mA·cm^(−2)for 1.0 mA·h·cm^(−2).Even at a higher current of 5.0 mA·cm^(−2),the TCC electrode can still stably cycle for 1,400 h.

关键词： K metal anode dendrite oxygen-rich treated carbon cloth K-philic sites ultra-long-life

CAR-T cells for cancer immunotherapy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国化学快报:英文版 2023年第9期34卷 55-64页

作者： yangyang xie Xiaotong Li Jingyi Wu Huiling Zeng Hamza Boucetta Binru Wang Pei Yang Wei He School of Pharmacy China Pharmaceutical UniversityNanjing 210000China School of Science China Pharmaceutical UniversityNanjing 210000China Shanghai Skin Disease Hospital Tongji University School of MedicineShanghai 200443China

Adoptive immunotherapy expressing synthetic chimeric antigen receptors(CAR)on T cells through in vitro modifications represents a new and innovative strategy in cancer treatment.This new approach enables T cells to recognize and bind tumor antigens via a single-chain variable fragment recognition domain,circumventing the restriction of major histocompatibility complex.This review summarized the structure/design of CAR-T cells and the evolution process this technology went through,displaying the theoretical foundation for CAR-T therapy,the marketed products and the latest preclinical and clinical research progress.Finally,we provided perspectives on this technology’s development and potential future applications,especially for treating hematological malignant and solid tumors.

关键词： CAR-T cells Cancer Immunotherapy Therapeutic techniques Marketed drugs Universal CAR-T Cell Therapy