Evolution of the effect of sulfur confinement in graphene-based porous carbons for use in Li-S batteries

Jia, Xiangling,Zhang, Chen,Liu, Juanjuan,Lv, Wei,Wang, Da-Wei,Tao, Ying,Li, Zhengjie,Zheng, Xiaoyu,Yu, Jong-Sung,Yang, Quan-Hong The Royal Society of Chemistry 2016 Nanoscale Vol.8 No.8

<P>A controllable drying strategy is proposed for the precise and non-destructive control over the structure of a 3D graphene assembly. Such an assembly is used as a model carbon material to investigate the pore structure-dependent shuttle effect and cycling performance of the cathode of a Li-S battery.</P>

Quantum Public-key Cryptosystem without Quantum Channels between Any Two Users using Non-orthogonal States

Xiaoyu Li,Yuwen Chen 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.9

A quantum public-key cryptosystem without quantum channels between any two users using non-orthogonal states is provided in this paper. Every user keeps a set of quantum particles in non-orthogonal states in a key management center (KMC) as the public key while he or she keeps the states of them as the private key. By the help of KMC users can accomplish secret communication and message authentication. The laws of quantum physics guarantee the unconditional security of this cryptosystem. No entangled states or complex quantum operations are needed. On the other hand there are no quantum channels needed to connecting any two users. So the public-key cryptosystem is easier to carry out and more robust in practice.

Ozone infusiblization and curing mechanism of polysilazane ceramic precursor fibers

Li Xiaohong,Luo Xiaoyu,Li Jing,Li Jinxia,Yang Jiahao,Ahmad Zahoor,Bao Zhihao,Zhang Xiao,Chen Jianjun 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.5

An appropriate infusible method plays a vital role as one of the key processes of the fabrication of polymer-derived ceramic fibers. In this work, ozone curing, a novel room temperature controllable curing strategy was used to prepare SiCN ceramic fibers. Some circular pores were observed on the surface of the obtained SiCN ceramic fibers. The tensile strength of the fibers was also investigated. To reveal the ozone-curing mechanisms of the PSZ fibers and the formation process of the circular pores, the FT-IR, SEM, OM, XRD and TG were characterized. The results showed that the Si–H bonds and Si-CH3 groups in the PSZ molecule were oxidized gradually to form oxygen-containing groups such as Si–OH, Si–O-Si and C = O in the ozone curing process, which contributed to the curing and weight gain of the PSZ fibers. Moreover, a hydrolysis reaction between Si-NH-Si and H2O might further accelerate the curing of the PSZ fibers. An unexpected result of the hydrolysis reaction is the formation of some circular pores on the surface layer of the PSZ fibers. This strategy provides a method to design, adjust and control the microstructure and composition of silicon-based ceramic fibers, and the obtained SiCN fibers may be used as catalyst support, bacterial culture and other fields.

Effect of Red Pepper (Capsicum frutescens) Powder or Red Pepper Pigment on the Performance and Egg Yolk Color of Laying Hens

Li, Huaqiang,Jin, Liji,Wu, Feifei,Thacker, Philip,Li, Xiaoyu,You, Jiansong,Wang, Xiaoyan,Liu, Sizhao,Li, Shuying,Xu, Yongping Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.11

Two experiments were conducted to study the effects of red pepper (Capsicum frutescens) powder or red pepper pigment on the performance and egg yolk color of laying hens. In Exp. 1, 210, thirty-wk old, Hy-line Brown laying hens were fed one of seven diets containing 0.3, 0.6, 1.2, 2.0, 4.8 or 9.6 ppm red pepper pigment or 0.3 ppm carophyll red. Each diet was fed to three replicate batteries of hens with each battery consisting of a row of five cages of hens with two hens per cage (n = 3). In Exp. 2, 180, thirty-wk old, Hyline Brown laying hens, housed similarly to those in Exp. 1, were fed an unsupplemented basal diet as well as treatments in which the basal diet was supplemented with 0.8% red pepper powder processed in a laboratory blender to an average particle size of $300{\mu}m$, 0.8% red pepper powder processed as a super fine powder with a vibrational mill ($44{\mu}m$) and finally 0.8% red pepper powder processed as a super fine powder with a vibrational mill but mixed with 5% $Na_2CO_3$ either before or after grinding. A diet supplemented with 0.3 ppm carophyll red pigment was also included (n = 3). In both experiments, hens were fed the red pepper powder or pigment for 14 days. After feeding of the powder or pigment was terminated, all hens were fed the basal diet for eight more days to determine if the dietary treatments had any residual effects. In Exp. 1, there were no differences in egg-laying performance, feed consumption or feed conversion ratio due to inclusion of red pepper pigment in the diet. Average egg weight was higher (p<0.05) for birds fed 1.2, 2.4 or 9.6 ppm red pepper pigment than for birds fed the diet containing 0.3 ppm red pepper pigment. On d 14, egg color scores increased linearly as the level of red pepper pigment in the diet increased. In Exp. 2, feeding red pepper powder did not affect egg-laying performance, feed consumption or feed conversion ratio (p>0.05). However, compared with the control group, supplementation with all of the red pepper powder treatments increased egg weight (p<0.05). All the red pepper powder treatments also increased (p<0.05) the yolk color score compared with the control. The results of the present study suggest that both red pepper powder and pigment are effective feed additives for improving egg yolk color for laying hens.

D-stability of generalized homogeneous cooperative time-varying systems

Xiaoyu Li,Yuangong Sun 제어로봇시스템학회 2023 제어로봇시스템학회 국제학술대회 논문집 Vol.2023 No.10

Effect of Paecilomyces cateniannulatus on the adsorption of nickel onto graphene oxide

Xiaoyu Li,Fengbo Li,Lejin Fang 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.12

Graphene oxide (GO) was synthesized by chemical oxidation method and used to remove nickel (Ni(II)) from aqueous solutions in the presence of Paecilomyces cateniannulatus (P. cateniannulatus). Based on characteristic results, it was demonstrated that P. cateniannulatus was easily combined with carboxyl groups of GO by covalent bond. The adsorption results showed that P. cateniannulatus facilitated the adsorption of Ni(II) on GO over a wide range of pH. The maximum adsorption capacities of GO+P. cateniannulatus and GO calculated from Langmuir model at pH 4.0 and T=303 K were 104.2 and 81.3mg·g−1, respectively. According to the analysis of thermodynamic parameters, the adsorption of Ni(II) on GO+P. cateniannulatus was endothermic and spontaneous. The highlight of this study quantitatively assessed the effect of bacteria on the fate and transports of heavy metals in near-surface geologic systems.

Dynamic Event-triggered Control for Heterogeneous Leader-following Consensus of Multi-agent Systems Based on Input-to-state Stability

Xiaoyu Li,Dazhong Ma,Xuguang Hu,Qiuye Sun 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.2

By utilizing dynamic event-triggered control strategy, this paper deals with consensus problem of a class of heterogeneous leader-following multi-agent systems(MASs) consisting of a high-dimensional leader system but low-dimensional following systems. A kind of observer-based consensus controllers is put forward with a dynamic event-triggered function consisting of the measurement error and a threshold based on the neighbors’ discrete states to reduce unnecessary utilization of limited communication and computation resources. Meanwhile, a dynamic variable is used to generate the event-triggered law using Input-to-State Stability(ISS) criteria. Based on this criteria, the proposed control strategy ensures stability of MASs, which fully reflects of the relationship between the external control inputs of the following systems and the internal states of the leader system and fully considered the influence of disturbances or noises on the MASs. Furthermore, the Zeno behavior for triggering time sequence is excluded. At last, a numerical simulation is provided to demonstrate the feasibility and effectiveness of the theoretical results.

Dendrite-like carbon nanotube-confined polymeric sulfur as cathode materials for lithium–sulfur battery

Li Xiaoyu,Zhang Zhehao,Zou Youlan,Li Zhaoyang,Duan Jinliang,Long Bo 한국탄소학회 2020 Carbon Letters Vol.30 No.5

We reported the synthesis of dendrite-like carbon nanotube-confned polymeric sulfur composite by modifying the surface of carbon nanotubes (CNTs) with trithiocyanuric acid (TTCA) and then copolymerizing with sulfur. DSC results show the successfully formation of robust chemical bonds between sulfur and TTCA modifed CNTs, which efectively avoid the dis-solution of polysulfde when used as cathodes for lithium–sulfur batteries. The composite with a high sulfur content of 78 wt% exhibits an initial charge capacity of 698 mAh g−1 and the residual capacity of 553 mAh g−1 after 1000 cycles at a rate of 1 C.

Performance of Mg-Ti modified iron-based catalyst in NH3-SCR of NO at the presence of arsenic: Influence of oxygen and temperature

Xiaoyu Li,Juan Chen,Shouyan Chen,Chunmei Lu,Guangqian Luo,Hong Yao 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.101 No.-

Impact of arsenic on the performance of Mg-Ti modified iron-based catalyst during selective catalyticreduction of NOx with ammonia was studied. The results indicated that Mg and Ti modification not onlyimproved the catalytic activity at 100–350 C, but also exhibited remarkable anti-arsenic ability. Mg wasdominant in the excellent anti-arsenic performance, and this role was firstly recognized. The anti-arsenicmechanism of Mg-Ti modified iron-based catalyst was ascribed to two aspects. One side, Mg exhibitedwell reactivity with arsenic which competed with Fe for the adsorption of arsenic and protected activeiron sites from arsenic occupation. The other side, presence of Mg promoted the formation of MgFe2O4in view of the strong interactions between Mg and Fe, suppressing the interactions between arsenicand Fe. Instead, gaseous arsenic turned to bond with Mg-O sites. Consequently, surface acid sites andfunction Fe-OH/ Fe = O bonds were preserved for de-NOx. Moreover, increase of oxygen content and temperatureweakened the deactivation of Mg-Ti modified iron-based catalyst by arsenic. It was due to theoxidation of As2O3 with oxygen content increase and the strengthened reactivity of non-active iron siteswith arsenic and Mg with arsenic as temperature elevation, inhibiting the interactions between activeiron sites with arsenic.

MECHANOCHEMICAL SYNTHESIS OF NiO NANOPARTICLES: INSIGHT INTO THE NATURE OF PREFERRED GROWTH ORIENTATION

XIAOYU LI,HUAMING YANG,LIANGJIE FU,TIANCHENG LIU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.4

Nickel oxide (NiO) nanoparticles were synthesized by calcination at 400?C to 700?C for 8 h of theprecursor obtained via mechanochemical reaction of Ni(NO 3 ) 2 ? 6 H 2 O with citric acid as a dis-persant. The nanoparticles were characterized by thermogravimetric-diferential scanningcalorimetry (TG-DSC), X-ray difraction (XRD) and transmission electron microscopy (TEM). The kinetics of diferent surfaces of the nanocrystals under nonisothermal conditions wasinvestigated. The activation energies for diferent lattice planes of NiO nanoparticles weredetermined using the Arrhenius equation, revealing their preferred orientation. The growth ofNiO obeyed the general theory that nanoparticles with the largest surface energy tend to form. XRD data reveal that the NiO nanoparticles possess preferred (111) or (200) orientations thatre°ect their complex activity. The nature of preferred growth orientation was found to benegative difusion activity among diferent lattice surfaces, which indicates that oxygen atomsdi®use from low oxygen concentration on the lattice surface to high concentration on the latticesurface.