Graphene–Ferroelectric Hybrid Structure for Flexible Transparent Electrodes

Ni, Guang-Xin,Zheng, Yi,Bae, Sukang,Tan, Chin Yaw,Kahya, Orhan,Wu, Jing,Hong, Byung Hee,Yao, Kui,Ö,zyilmaz, Barbaros American Chemical Society 2012 ACS NANO Vol.6 No.5

<P>Graphene has exceptional optical, mechanical, and electrical properties, making it an emerging material for novel optoelectronics, photonics, and flexible transparent electrode applications. However, the relatively high sheet resistance of graphene is a major constraint for many of these applications. Here we propose a new approach to achieve low sheet resistance in large-scale CVD monolayer graphene using nonvolatile ferroelectric polymer gating. In this hybrid structure, large-scale graphene is heavily doped up to 3 × 10<SUP>13</SUP> cm<SUP>–2</SUP> by nonvolatile ferroelectric dipoles, yielding a low sheet resistance of 120 Ω/□ at ambient conditions. The graphene–ferroelectric transparent conductors (GFeTCs) exhibit more than 95% transmittance from the visible to the near-infrared range owing to the highly transparent nature of the ferroelectric polymer. Together with its excellent mechanical flexibility, chemical inertness, and the simple fabrication process of ferroelectric polymers, the proposed GFeTCs represent a new route toward large-scale graphene-based transparent electrodes and optoelectronics.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2012/ancac3.2012.6.issue-5/nn3010137/production/images/medium/nn-2012-010137_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn3010137'>ACS Electronic Supporting Info</A></P>

Generation of Hydrogen Peroxide by Single-Atom Clusters Pd Anchored on t-BaTiO3 for Piezoelectric Degradation of Tetracycline

Xin Ni,Yuan Liang,Quanzi Pan,Hengjie Guo,Kai Chen,Bo Zhang,Shaocong Ni,Bin Sheng,Zeda Meng,Shouqing Liu,오원춘 한국재료학회 2023 한국재료학회지 Vol.33 No.11

Single-atom Pd clusters anchored on t-BaTiO3 material was synthesized using hydrothermal and ultrasonic methods for the effective piezoelectric catalytic degradation of pollutants using vibration energy. XRD patterns of BaTiO3 loaded with monoatomic Pd were obtained before and after calcining, and showed typical cubic-phase BTO. TEM and HAADF-STEM images indicated single-atom Pd clusters were successfully introduced into the BaTiO3. The piezoelectric current density of the prepared Pd-BaTiO3 binary composite was significantly higher than that of the pristine BaTiO3. Under mechanical vibration, the nanomaterial exhibited a tetracycline decomposition rate of ~95 % within 7 h, which is much higher than the degradation rate of 56.7 % observed with pure BaTiO3. Many of the piezo-induced electrons escaped to the Pd-doped BaTiO3 interface because of Pd’s excellent conductivity. Single-atom Pd clusters help promote the separation of the piezo-induced electrons, thereby achieving synergistic catalysis. This work demonstrates the feasibility of combining ultrasonic technology with the piezoelectric effect and provides a promising strategy for the development of ultrasonic and piezoelectric materials.

Quasi-Periodic Nanoripples in Graphene Grown by Chemical Vapor Deposition and Its Impact on Charge Transport

Ni, Guang-Xin,Zheng, Yi,Bae, Sukang,Kim, Hye Ri,Pachoud, Alexandre,Kim, Young Soo,Tan, Chang-Ling,Im, Danho,Ahn, Jong-Hyun,Hong, Byung Hee,Ö,zyilmaz, Barbaros American Chemical Society 2012 ACS NANO Vol.6 No.2

<P>The technical breakthrough in synthesizing graphene by chemical vapor deposition methods (CVD) has opened up enormous opportunities for large-scale device applications. To improve the electrical properties of CVD graphene grown on copper (Cu-CVD graphene), recent efforts have focused on increasing the grain size of such polycrystalline graphene films to 100 μm and larger. While an increase in grain size and, hence, a decrease of grain boundary density is expected to greatly enhance the device performance, here we show that the charge mobility and sheet resistance of Cu-CVD graphene is already limited within a single grain. We find that the current high-temperature growth and wet transfer methods of CVD graphene result in quasi-periodic nanoripple arrays (NRAs). Electron-flexural phonon scattering in such partially suspended graphene devices introduces anisotropic charge transport and sets limits to both the highest possible charge mobility and lowest possible sheet resistance values. Our findings provide guidance for further improving the CVD graphene growth and transfer process.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2012/ancac3.2012.6.issue-2/nn203775x/production/images/medium/nn-2011-03775x_0005.eps'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn203775x'>ACS Electronic Supporting Info</A></P>

A novel hybrid compound fault pattern identification method for gearbox based on NIC, MFDFA and WOASVM

Xin Zhang,Jianmin Zhao,Xinghui Zhang,Xianglong Ni,Haiping Li,Fucheng Sun 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.3

Gearbox compound fault pattern recognition is challenging because of its complexity and non-stationarity of the vibration signal. In this study is proposed a novel hybrid method based on narrow band interference canceller (NIC), multifractal detrended fluctuation analysis (MFDFA) and support vector machine optimized by whale optimization algorithm (WOASVM) for compound fault pattern recognition of gearbox. Specifically, the raw signal is processed by NIC to filter the deterministic signal which interferes with the fault signal, and then the multifractal features are extracted from the residual signal via MFDFA. Finally, the compound fault pattern is identified via WOASVM. Compound fault experiments of a gearbox under fixed condition and variable condition were done to evaluate the performance of the proposed method. The results show that the proposed method can effectively identify the compound faults and it outperforms other methods mentioned in this paper.

Effects of Different Colored Light-quality Selective Plastic Films on Growth, Photosynthetic Abilities, and Fruit Qualities of Strawberry

Xin Peng,Bin Wang,Xile Wang,Binbin Ni,Zhaojiang Zuo 한국원예학회 2020 원예과학기술지 Vol.38 No.4

Light quality regulates plant growth and photosynthesis, the drivers of fruit quality, and light quality can be controlled by colored light-quality selective plastic films in field production. To identify the optimal color of plastic film for high-quality strawberry (Fragaria × ananassa) fruit production, plant growth, photosynthetic abilities, and fruit qualities were investigated under transparent (T), red (R), yellow (Y), green (G), blue (B), and purple (P) films. The R film showed the maximum promoting effects on leaf area, petiole length, leaf biomass, and shoot biomass. The R film improved photosynthetic abilities by increasing photosynthetic pigment content, quantum yield (φPo), electron transfer (Ψo and φEo), the density of reaction centers (RC/CSm), and the photosynthetic performance index (PIabs), and by decreasing the dissipation of absorbed solar energy as heat (φDo), while varied reverse effects were detected under other films. For fruit qualities, the R film also improved fruit weight and the content of total sugar, anthocyanin, and soluble protein. Therefore, the R light-quality selective plastic film should be suitable for strawberry production due to the promoting effects on plant growth, photosynthetic abilities, and fruit weight and quality.

Performance Comparison of Surface-Inset Machines With Two Layer Equal/Unequal Magnet-Arc Halbach Magnets

Ni Youyuan,Zhang Xin,Chen Qiuming,Huang Ya,Wang Qunjing 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.3

The electromagnetic performances of surface-inset machines with two layer equal/unequal magnet-arc Halbach magnets are compared. The magnetic feld distribution is analytically obtained by analyzing the outer/inner layer Halbach magnets separately. Through presented analytical technique, the magnetization angles of each layer Halbach magnets are analytically optimized. Considering the practical application of relatively large usage of magnets, the larger the outer layer magnet-arc ratio, the better the performances. The analytical predictions show that the optimal two layer unequal magnet-arc Halbach machine has a much higher sine degree of both the airgap fux density and the back-electromotive force and a much lower torque ripple than the optimal two layer equal magnet-arc Halbach machine. The fnite element analysis and analytical prediction results are compared.

Soil moisture retrieval in farmland using C-band SAR and optical data

Xin Zhao,Ni Huang,Zheng Niu,Venkatesh Raghavan,Xianfeng Song 대한공간정보학회 2017 Spatial Information Research Vol.25 No.3

Soil moisture retrieval in vegetation-covered area with space borne synthetic aperture radar is a challenging process due to the impact of vegetation on the multiple scattering of electromagnetic wave. In this paper, a semi-empirical method is proposed to estimate farmland soil moisture by active microwave remote sensing and optical remote sensing. By integrating the vegetation water content estimated from optical data and thermal infrared data into a coupling model based on a water–cloud model, the influence of vegetation on microwave backscattering coefficient was eliminated and thus soil moisture in vegetation-covered area was accurately retrieved. The experiment of soil moisture retrieval was carried out using Radarsat-2 and Landsat 8 datasets in western Great Khingan Mountains, Inner Mongolia, China. The research showed that the accuracy of the coupling model is high and the R2 is up to 0.69 using HH polarization. Moreover, the effects of crop types on soil moisture retrieval, particularly barley, could also be distinguished using the coupling model.

The Inhibition Effect of Triptolide on Human Endometrial Carcinoma Cell Line HEC-1B: a in vitro and in vivo Studies

Ni, Jing,Wu, Qiang,Sun, Zhi-Hua,Zhong, Jian,Cai, Yu,Huang, Xin-En Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.11

Background: To investigate the inhibitory effect and the underlying mechanism of triptolide on cultured human endometrial carcinoma HEC-1B cells and corresponding xenograft. Materials and Methods: For in vitro studies, the inhibition effect of proliferation on HEC-1B cell by triptolide was determined by MTT assay; cell cycle and apoptosis of the triptolide-treated and untreated cells were detected by flow cytometry. For in vivo studies, a xenograft tumor model of human endometrial carcinoma was established using HEC-1B cells, then the tumor-bearing mice were treated with high, medium, and low-dose ($8{\mu}g$, $4{\mu}g$ and $2{\mu}g/day$) triptolide or cisplatin at $40{\mu}g/day$ or normal saline as control. The mice were treated for 10-15 days, during which body weight of the mice and volume of the xenograft were weighted. Then expression of Bcl-2 and vascular endothelial growth factor (VEGF) was analyzed by SABC immunohistochemistry. Results: Cell growth was significantly inhibited by triptolide as observed by an inverted phase contrast microscope; the results of MTT assay indicated that triptolide inhibits HEC-1B cell proliferation in a dose and time-dependent manner; flow cytometry showed that low concentration (5 ng/ml) of triptolide induces cell cycle arrest of HEC-1B cells mainly at S phase, while higher concentration (40 or 80 ng/ml) induced cell cycle arrest of HEC-1B cells mainly at G2/M phase, and apoptosis of the cells was also induced. High-dose triptolide showed a similar tumor-inhibitory effect as cisplatin (-50%); high-dose triptolide significantly inhibited Bcl-2 and VEGF expression in the xenograft model compared to normal saline control (P<0.05). Conclusions: triptolide inhibits HEC-1B cell growth both in vitro and in mouse xenograft model. Cell cycle of the tumor cells was arrested at S and G2/M phase, and the mechanism may involve induction of tumor cell apoptosis and inhibition of tumor angiogenesis.

Functional Roles of Long Non-coding RNA in Human Breast Cancer

Ye, Ni,Wang, Bin,Quan, Zi-Fang,Cao, San-Jie,Wen, Xin-Tian,Huang, Yong,Huang, Xiao-Bo,Wu, Rui,Ma, Xiao-Ping,Yan, Qi-Gui Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

The discovery of long noncoding RNA (LncRNA) changes our view of transcriptional and posttranscriptional regulation of gene expression. With application of new research techniques such as high-throughput sequencing, the biological functions of LncRNAs are gradually becoming to be understood. Multiple studies have shown that LncRNAs serve as carcinogenic factors or tumor suppressors in breast cancer with abnormal expression, prompts the question of whether they have potential value in predicting the stages and survival rate of breast cancer patients, and also as therapeutic targets. Focusing on the latest research data, this review mainly summarizes the tumorigenic mechanisms of certain LncRNAs in breast cancer, in order to provide a theoretical basis for finding safer, more effective treatment of breast cancer at the LncRNA molecular level.

Studies of Extraction Techniques for Tea Volatile Compounds

Juan-Zhen Ni,Fang-Li Zhao,Jian Liang Lu,Xin-Qiang Zheng 한국차학회 2015 한국차학회지 Vol.- No.S

Hundred of kinds of volatiles have been found in tea products. Their characters are in low amounts, complex composition, volatile and unstable. Volatiles extraction process would easily give rise to oxidation or other numbers of physical and chemical reactions. Ten kinds of extraction techniques commonly used for tea volatile compounds are described in present paper, namely Brewed extraction, Ultrasonic-assisted extraction, Adsorptive column method, Organic solvents extraction, Simultaneous distillation extraction (SDE), Steam distillation under reduced pressure (SDR), Supercritical fluid extraction (SFE), Solid phase micro-extraction (SPME), Simultaneous multiple solid-phase, and Dynamic headspace extraction (DHE). For extracting tea volatiles, each of these techniques has advantages and limitation. Some proposals were provided for selecting a favorable extraction method for tea volatile compounds.