First-principle study on catalytic activity of functionalized Ti3C2 MXene as cathode catalyst for Li–O2 batteries

Yang Yingying,Chen Jian,Gao Qiqian,Feng Yu,Xing Fei,Yao Man 한국물리학회 2022 Current Applied Physics Vol.34 No.-

Two-dimensional layered Ti3C2, one representative MXene, is notable as promising cathode catalyst for rechargeable lithium-oxygen (Li–O2) batteries. Using first-principles calculations, we construct cathode electrochemical interface catalytic model to simulate the structural evolution during discharging and charging processes, and the calculated ORR, OER and TOT overpotentials are used to quantitatively assess the catalytic activity of Ti3C2 MXene with and without O, F and OH functional groups. Interestingly, we find that the catalytic activity follows such a trend: Ti3C2O2>Ti3C2F2>Ti3C2(OH)2>Ti3C2, which suggests that O-terminated Ti3C2 MXene has great advantages and potentiality for catalyzing ORR and OER in Li–O2 batteries. This is caused by Ti3C2O2 surface shows stronger oxidation capability toward O22 compared to Ti3C2F2, Ti3C2(OH)2 and Ti3C2. The present study may provide a guideline to accelerate ORR and OER reactions of Ti3C2 MXene as cathode catalyst in Li–O2 batteries, with O-terminated group being taken into consideration.

In situ Copolymerized Toughened Polymethyl Methacrylate (PMMA) with Highly Transparency for Support Film of Polarizers

Yingying Wang,Bin Yang,Liangyong He,Yuqing Yang,Nuo Zhang,Yang Wang,Zhiqiang Shi,Yuchao Ke,Lifen Su,Jia-Sheng Qian,RU XIA,Tao Jiang 한국고분자학회 2022 폴리머 Vol.46 No.5

In this study, a series of poly(methyl methacrylate) (PMMA) copolymer films were prepared via solutionpolymerization of methyl methacrylate (MMA) with butyl acrylate (BA) and lauryl methacrylate (LMA) as monomers. Mechanical properties, hydrophobic properties, and optical properties of the films were intensively investigated. The rheological results showed that the fluidity of the copolymer was considerably enhanced. When the monomer ratio ofMMA:BA:LMA was 100:30:10, the copolymer film S4 showed the best overall performance with perfect optical transparency maintained. The results of the dynamic mechanical and thermal analysis suggested that the glass transition temperature (Tg) moved towards lower temperature, with enhanced ductility of the PMMA films. A large number of yieldfolds and crazes appeared on the cross-sectional surface of copolymer films through morphological observations, displaying the obvious characteristics of toughness fracture and obeying the energy dissipation mechanism of cracks shearband. The present study provided a facile way of preparing PMMA films with high toughness and light transmittanceby appropriate selection of the monomers, which will be of practical significance for further studies on the replacementof triacetyl cellulose as a support film of polarizers.

Improving the charge transfer performance of Si nanomaterial through C surface modification: A first-principles study

Yingying Yang,Xiaowan Xue,Yuan Qin,Hao Huang,Xudong Wang,Man Yao 한국물리학회 2019 Current Applied Physics Vol.19 No.7

Models of oxidized Si (111) surface under different C coverage were established to study the charge transfer ability of Si nanomaterial from strategy of C surface modification using first-principles calculation. The calculated formation energies show that structures of C surface-modified oxidized Si (111) surface are stable. The electronic properties present that the interaction between C and Si atoms is mainly contributed by the hybridization of C-2p and Si-3p states. And the interaction between C and Si atoms increases firstly and then decreases with the increasing C coverage rate. The transfer charge between C and Si reaches a maximum when C coverage rate is 0.5. We speculate that the conductivity of experimentally prepared Si nanomaterial does not monotonously enhance with the increasing C concentration, which would reach a maximum at a certain C concentration, and then decreases.

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.

Bone Morphogenetic Protein 9 Overexpression Reduces Osteosarcoma Cell Migration and Invasion

Zilan Lv,Ya-guang Weng,Dandan Yang,Jie Li,Min Hu,Min Luo,Xiaoqin Zhan,Peipei Song,Chen Liu,Huili Bai,Baolin Li,Yang Yang,Yingying Chen,Qiong Shi 한국분자세포생물학회 2013 Molecules and cells Vol.36 No.2

Transforming growth factor- (TGF-) is known to pro-mote tumor migration and invasion. Bone morphogenetic proteins (BMPs) are members of the TGF- family expressed in a variety of human carcinoma cell lines. The role of bone morphogenetic protein 9 (BMP9), the most powerful osteogenic factor, in osteosarcoma (OS) progression has not been fully clarified. The expression of BMP9 and its receptors in OS cell lines was analyzed by RT-PCR. We found that BMP9 and its receptors were expressed in OS cell lines. We further investigated the influence of BMP9 on the biological behaviors of OS cells. BMP9 overexpression in the OS cell lines 143B and MG63 inhibited in vitro cell migration and invasion. We further investigated the ex-pression of a panel of cancer-related genes and found that BMP9 overexpression increased the phosphorylation of Smad1/5/8 proteins, increased the expression of ID1, and reduced the expression and activity of matrix metalloproteinase 9 (MMP9) in OS cells. BMP9 silencing induced the opposite effects. We also found that BMP9 may not affect the chemokine (C-X-C motif) ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) axis to regulate the invasiveness and metastatic capacity of OS cells. Interestingly, CXCR4 was expressed in both 143B and MG63 cells, while CXCL12 was only detected in MG63 cells. Taken together, we hypothesize that BMP9 inhibits the migration and invasiveness of OS cells through a Smad-dependent pathway by downregulating the expression and activity of MMP9.

A Global Optimization Algorithm Based on <tex> $C^{1}$</tex> Piecewise Response Surface Patches

Yingying Yao,Chang Seop Koh,Shiyou Yang,Guangzheng Ni IEEE 2007 IEEE transactions on magnetics Vol.43 No.4

<P>A new surrogate objective function is suggested for the global optimization of electromagnetic devices. The surrogate objective function is constructed using a C<SUP>1</SUP> piecewise response surface incorporated with the design sensitivities computed by using the finite-element method. The sampling data points used for constructing the response surface are adaptively inserted during the optimization process. After the surrogate objective function is constructed, the global optimum point is obtained by using a genetic algorithm. Applications to benchmark problems and the optimum design of a permanent magnet system show the effectiveness of the proposed algorithm</P>

Design and Evaluation of a Social Networking Site (SNS) Supported Collaborative Learning Environment for Vocabulary Learning

YANG Wanping,PAN Yingying 한국교육공학회 2022 Educational Technology International Vol.23 No.1

Vocabulary learning plays an important role in language learning. This study explored a new paradigm based on social networking site (SNS) supported collaborative learning for vocabulary learning. SNS supported collaborative learning (SSCL) can effectively promote learners’ engagement, interest and motivation by providing a more communicative and interactive environment. However, vocabulary learning studies on SSCL mainly focused on the effectiveness and influencing factors, lacking specific instructional strategies. Therefore, this study aims to develop instructional strategies that guide instructors to create an SSCL environment for facilitating vocabulary learning. The final instructional strategies are composed of three stages according to the course process, consisting of 8 general strategies and 21 specific guidelines. The content validity was ensured by four experts in the field of educational technology. The instructional strategies were then applied in an actual classroom with 16 students. The positive responses from the instructor and learners indicated that SSCL can be reasonably incorporated into the current curriculum to provide effective learning opportunities and to promote learners’ vocabulary learning.

An Adaptive Watermark Detection Algorithm for Vector Geographic Data

( Yingying Wang ),( Chengsong Yang ),( Na Ren ),( Changqing Zhu ),( Ting Rui ),( And Dong Wang ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.1

With the rapid development of computer and communication techniques, copyright protection of vector geographic data has attracted considerable research attention because of the high cost of such data. A novel adaptive watermark detection algorithm is proposed for vector geographic data that can be used to qualitatively analyze the robustness of watermarks against data addition attacks. First, a watermark was embedded into the vertex coordinates based on coordinate mapping and quantization. Second, the adaptive watermark detection model, which is capable of calculating the detection threshold, false positive error (FPE) and false negative error (FNE), was established, and the characteristics of the adaptive watermark detection algorithm were analyzed. Finally, experiments were conducted on several real-world vector maps to show the usability and robustness of the proposed algorithm.

Correlation analysis of muscle amino acid deposition and gut microbiota profile of broilers reared at different ambient temperatures

Yang, Yuting,Gao, Huan,Li, Xing,Cao, Zhenhui,Li, Meiquan,Liu, Jianping,Qiao, Yingying,Ma, Li,Zhao, Zhiyong,Pan, Hongbin Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.1

Objective: Temperature could influence protein and amino acid deposition as well as gut microbiota profile and composition. However, the specific effects of ambient temperature on amino acids deposition and gut microbiota composition remain insufficiently understood. Methods: A total of 300 one-day-old Avian broilers were randomly divided into three groups and reared at high, medium, and low temperature (HT, MT, and LT), respectively. Breast muscle and fecal samples were collected for amino acid composition analysis and 16S rRNA gene sequence analysis. Results: Our data showed that compared to the MT group, there was a decrease of muscle leucine and tyrosine (p<0.05), as well as an increase of methionine in the HT group (p<0.05) and a decrease of serine in the LT group. Examination of microbiota shift revealed that at genus level, the relative abundance of Turicibacter and Parabacteroides was increased in the HT group (p<0.05) and that the relative abundances of Pandoraea, Achromobacter, Prevotella, Brevundimonas, and Stenotrophomonas in the LT group were higher than those in the MT group (p<0.05). In addition, there were substantial correlations between microbes and amino acids. In the HT group. Turicibacter was negatively correlated with aspartic acid and tyrosine, whereas Parabacteroides was positively correlated with methionine (p<0.05). In the LT group, there were multiple positive correlations between Achromobacter and arginine, isoleucine or tyrosine; between Prevotella and cysteine or phenylalanine; between Brevundimonas and cysteine; and between Stenotrophomonas and cysteine as well as a negative correlation between Stenotrophomonas and serine. Conclusion: Our findings demonstrated that amino acid content of breast muscle and intestinal microbiota profile was affected by different ambient temperatures. Under heat exposure, augmented abundance of Parabacteroides was correlated with elevated methionine. Low temperature treatment may affect muscle tyrosine content through the regulation of Achromobacter.

Research on the mechanical properties of membrane connections in tensioned membrane structures

Yingying Zhang,Qilin Zhang,Yang Li,Lu Chen 국제구조공학회 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.49 No.6

As an important part, the connections generally are important for the overall behavior of the structure and the strength and serviceability of the connection should be ensured. This paper presents the mechanical properties of membrane connections in tensioned membrane structure. First, the details of common connections used in the membrane structure are introduced. Then, the common connections including membrane seam, membrane-flexible edge connection and membrane-rigid edge connection are tested and the corresponding failure mechanisms are discussed. Finally, the effects of connection parameters on the connection strength are investigated and proper connection parameters are proposed. The strength reduction factors corresponding to different connection types are proposed, which can be references for the design and analysis of membrane structures.