Effects of Ce and Nb additives on the de-NOx performance of SCR/CDPF system based on Cu-beta zeolite for diesel vehicles

Zhao, Yingying,Choi, Byungchul,Kim, Daeseok Elsevier 2017 Chemical engineering science Vol.164 No.-

<P><B>Abstract</B></P> <P>In this study, the de-NOx performance of the Cu-beta zeolite (BEA) selective catalytic reduction (SCR) catalyst with Ce and Nb as additives was investigated for the diesel catalytic reduction catalyzed diesel particulate filter (SCR/CDPF) system. The Cu-BEA catalyst with the Ce and Nb additives improved the NOx conversion, compared to the Cu-BEA catalyst without additives, under conditions of both standard and fast SCR reaction. This result is related to the strength of the intensity ratio as (Cu2p3 B peak)/(Cu2p3 A peak) for the Ce and Nb added catalysts. At the aging temperature of >650°C, the Cu-BEA-Nb catalyst showed better de-NOx performance than the other catalysts, because the Nb<SUB>2</SUB>O<SUB>5</SUB> (Nb<SUP>5+</SUP>) of the aged Cu-BEA-Nb catalyst remained. The Cu-BEA-CeNb catalyst was most affected by HC, and the addition of Nb to the Cu-BEA catalyst improved the oxidation ability and inhibited the HC poison at a high temperature.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ce and Nb additives improved the NOx conversion of pristine Cu-BEA. </LI> <LI> Addition of Nb to Cu-BEA improved oxidation ability and inhibited HC poisoning. </LI> <LI> Cu-BEA-Nb was the most promising catalyst for application in diesel SCR/CDPF. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Improvement of NOx conversion with different additives into Cu based SCR/CDPF catalyst

Yingying Zhao(조영영),Byungchul Choi(최병철),Wooseog Kang(강우석) 한국자동차공학회 2015 한국자동차공학회 학술대회 및 전시회 Vol.2015 No.11

Shaking Table Test on Composite Isolation System of High-speed Railway Station with Integrated Station-Bridge Structure

Yingying Zhang,Penghao Yu,Baorui Sun,Yi Zhou,Peijian Chen,Junhao Xu,Yushuai Zhao 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.2

This paper investigated the seismic performance of a typical “Integrated Station-Bridge high-speed railway station structure with a composite isolation system. The influential mechanism of the structure with isolation system was analyzed based on shaking table tests, mainly investigating on the failure mode, acceleration response and displacement response. Besides, a parameter optimization method of isolation layer for long-span structures was proposed based on genetic algorithm to better enhance the isolation performance of the large-span structure. The research revealed that there was no obvious damage to the composite isolation system under the PGA = 0.82 g. The nature frequency of the structure with isolation system is only 12.5% of that of non-isolation structure. The first three natural vibration frequency of the structure with isolation system only reduce 3.4%, 3.2%, 6.14% after the PGA = 1.27 g, that of the non-isolation structure reduce by more than 20%. The acceleration amplification factor of each layer of composite isolation system is less than 1, in particular, that of truss is about 0.3. The displacement response and acceleration response of the structure with isolation system have been reduced by about 90%. The proposed optimization method of isolation layer parameters provides an important reference for the isolation design for high-speed railway stations.

Research on the Multi-channel P-persistent CSMA Protocol with Monitoring Function

Yingying Guo,Jing Nan,Hongwei Ding,Yifan Zhao,Shengjie Zhou 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.5

This paper presents a new sensor network MAC protocol: the multi-channel p - persistent CSMA protocol with monitoring function (ACKPPCMA) from the perspective of improving the channel utilization and meeting the demand of the high QoS for high priority. Analyze the model by using the average cycle method. The Computer simulation results verify the correctness of the theory. Has some practical significance.

UBE2W Interacts with FANCL and Regulates the Monoubiquitination of Fanconi Anemia Protein FANCD2

Yingying Zhang,Peitang Huang,Xiaowei Zhou,Lixia Zhao,Chao Li,Hengqi Zhu,Long Xu,Liran Shan,Xiang Liao,Zekun Guo 한국분자세포생물학회 2011 Molecules and cells Vol.31 No.2

Fanconi anemia (FA) is a rare cancer-predisposing ge-netic disease mostly caused by improper regulation of the monoubiquitination of Fanconi anemia complementation group D2 (FANCD2). Genetic studies have indicated that ubiquitin conjugating enzyme UBE2T and HHR6 could regulate FANCD2 monoubiquitination through distinct mechanisms. However, the exact regulation mechanisms of FANCD2 monoubiquitination in response to different DNA damages remain unclear. Here we report that UBE2W, a new ubiquitin conjugating enzyme, could regulate FANCD2 monoubiquitination by mechanisms different from UBE2T or HHR6. Indeed, UBE2W exhibits ubiquitin conjugating enzyme activity and catalyzes the monoubiquitination of PHD domain of Fanconi anemia complementation group L (FANCL) in vitro. UBE2W binds to FANCL, and the PHD domain is both necessary and sufficient for this interaction in mammalian cells. In addition, over-expression of UBE2W in cells promotes the monoubiquitination of FANCD2 and down-regulated UBE2W markedly reduces the UV irradia-tion-induced but not MMC-induced FANCD2 monoubiquiti-nation. These results indicate that UBE2W regulates FANCD2 monoubiquitination by mechanisms different from UBE2T and HRR6. It may provide an additional regulatory step in the activation of the FA pathway.

Numerical study on tensioned membrane structures under impact load

Yingying Zhang,Yushuai Zhao,Mingyue Zhang,Yi Zhou,Qilin Zhang 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.71 No.2

This paper presents the numerical simulation of membrane structure under impact load. Firstly, the numericalsimulation model is validated by comparing with the test in Hao’s research. Then, the effects of the shape of the projectile, themembrane prestress and the initial impact speed, are investigated for studying the dynamic response and failure mechanism, basedon the membrane displacement, projectile acceleration and kinetic energy. Finally, the results show that the initial speed and thepunch shape are related with the loss of kinetic energy of projectiles. Meanwhile, the membrane prestress is an important factor thataffects the energy dissipation capacity and the impact resistance of membrane structures.

Understanding of crystallization behavior under low melt temperatures of propylene-ethylene copolymer with different initial polymorphs

Jiayi Zhao,Yingying Sun,Yongfeng Men 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

CDK1 promotes the proliferation of melanocytes in Rex rabbits

Dai Yingying,Hu Shuaishuai,Bai Shaocheng,Li Jiali,Yang Naisu,Zhai Pin,Zhao Bohao,Chen Yang,Wu Xinsheng 한국유전학회 2022 Genes & Genomics Vol.44 No.10

Background: The fur color constitutes one of the most important economic characteristics of fur animals and is determined by the content of melanin. A previous study has shown that the cyclin-dependent kinase 1 (CDK1) is a member of the protein kinase family, involved in forming the color of the fur in Rex rabbits. However, its effect on the melanocytes remains unclear. Objective: This study aimed to provide evidence for the role of CDK1 in melanogenesis. Methods: This study measured the expression of CDK1 in Rex rabbit skins of six coat colors using qRT-PCR. The CDK1-mediated regulation of the pigmentation-related genes and cyclin-dependent kinases were analyzed. The melanin content, proliferation, and apoptosis of the melanocytes were analyzed using the NaOH, CCK8, and Annexin V-FITC methods. Results: The CDK1 expression in the skin of the rex rabbits with different coat colors was found to be regular, and the expression level was found to be the highest in the skin of the black rex rabbits (P < 0.05). The overexpression/knockdown of CDK1 was found to significantly increase/decrease the melanin content in the melanocytes (P < 0.01). Besides, CDK1 was found to significantly promote the proliferation of the melanocyte and inhibit apoptosis (P < 0.01). Furthermore, the overexpression of CDK1 was found to significantly affect the expression of the other melanin-related genes like TYR, PMEL, DCT, as well as the mRNA expression of the cyclin-dependent kinases CDK4, CDK6, CDK8, CCNB1. Conclusions: The results indicated that CDK1 can serve as a key gene regulating melanogenesis, melanocyte proliferation, and apoptosis, providing a new theoretical basis for studying the mechanism by which the different colors of the fur evolve in mammals.

Microcapsules derived from Pickering emulsions as thermal latent curing accelerator for epoxy resins

Bowen Zhang,Yingying Zhao,Xin Sun,Xiaoma Fei,Weiwei Wang,Xiaojie Li,Xiaoya Liu 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.83 No.-

Organic-inorganic hybrid microcapsules encapsulating 2-phenylimidazole (2-PhIm) were prepared byPickering emulsion polymerization of styrene and divinyl benzene using methacryloyloxy silanemodifiedsilica particles as the stabilizer, and served as a thermal latent curing accelerator fordiglycidylether of bisphenol A epoxy/anhydride system. The one-component curing compositioncontaining 5 wt% of the microcapsules exhibited an excellent storage stability. The pot life at roomtemperature was as long as 30 days, while which of 2-PhIm curing system was only 2 days. At elevatedtemperature, the encapsulated 2-PhIm could be released from microcapsules effectively, and instantlyaccelerated the curing reaction. Meanwhile, the addition of microcapsules did not cause an adverse effecton the thermomechanical performance of the epoxy thermosets. In addition, the latency and curingbehavior could be facilely regulated at a wide range of temperature by adjusting monomer ratios of thepolymer matrix, to match different process temperatures. The microcapsules with robust cross-linkedpolystyrene matrix structure also showed good resistance to shearing forces, indicating their feasibilityfor high-speed mixing or kneading process in practical applications. It is suggested that the novel latentcuring accelerator is potential for high-performance one-pot epoxy formulations, particularlyrecommended for application in electronic packagingfields.

Simultaneous desulfurization and denitrogenation of model fuels by polyethylene glycol-modified resorcinol/formaldehyde resin-derived carbon spheres

Jie Wen,Dongdong Zhao,Yingying Lu,Jing Huang,Yanping Li,Hui Zhang,Airong Li 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.7

A series of resorcinol/formaldehyde (RF) resin-derived carbon spheres modified by polyethylene glycol (PEG) were prepared. The effects of PEG addition time during hydrothermal treatment and molecular weight on the pore structure, surface acidic groups, particle size, and adsorption performances of the obtained spherical activated carbons were investigated. Two types of model fuel containing indole, quinoline, and dibenzothiophene (DBT) as target adsorbates were prepared to evaluate the adsorption performances of the spheres, which increased in the order of DBT<quinoline<indole. Hydrogen bonding may be critical in the removal of indole. Both the surface area and oxygen- containing functional groups influenced the adsorption capacity, with the latter significantly influenced by PEG addition time. PEG addition during the RF resin cross-linking stage sharply reduced the total concentration of acidic groups on the carbon sphere surfaces. The adsorption thermodynamics and kinetics of nitrogen and sulfur compounds were also investigated. The adsorption isotherms of all S/N species were of the Freundlich type at 25 oC. The pseudo-second-order rate equation well described the adsorption kinetics. Both external diffusion and intra-particle diffusion controlled the rate of adsorption.