Direct observation of the hysteretic Fermi level modulation in monolayer MoS2 field effect transistors

Yuhang Wang,Dongyong Li,Xubo Lai,Boyang Liu,Yibao Chen,Fengping Wang,Rongming Wang,Liuwan Zhang 한국물리학회 2020 Current Applied Physics Vol.20 No.2

The hysteresis in the transfer curve of MoS2 has significant impact on the device performance. However, the hysteresis mechanism is still not clear. Here, we investigate the hysteresis of the monolayer MoS2 by probing the local Fermi level variations as a function of the back gate voltage in different atmosphere using the Kelvin probe microscopy. While the Fermi level of the MoS2 in air is much lower than that in vacuum, both the MoS2 devices in vacuum and air show large Fermi level hysteresis. The Fermi level hysteresis direction is clock-wise, identical to that observed in the transfer curves. Both the hysteresis in Fermi level and transfer curve can be explained consistently by taking into account the charge trapping. Our findings confirm that carrier density modulation in MoS2 plays a vital role in the hysteresis, and provide insight into the hysteresis mechanism for the optimization of the device performance.

Sequential Prediction of the TBM Tunnelling Attitude Based on Long-Short Term Memory with Mechanical Movement Principle

Ruirui Wang,Yuhang Xiao,Qian Guo,Hai Wang,Lingli Zhang,Yaodong Ni 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.2

TBM tunnelling attitude controlling is a significant issue for guaranteeing the tunnel fitting the expected tunnel axis, with directly influence the tunnel quality. The key to solve the problem is to establish the relationship between the tunnelling attitude and the controlling parameters and to predict the tunnelling attitude accordingly. For this, this paper introduced a TBM tunnelling attitude predicting method. In detail, using Long-Short Term Memory (LSTM), the initial tunnelling attitude and the controlling parameters of each later ring are taken as input, while the tunnelling attitude of each later rings are regarded as the output, and the relationship between the input and output is established. Meanwhile, for avoid the over-fitting and error accumulation risk of LSTM, the theoretical relationship between the input and output is also built based on the TBM mechanical movement principle, and it is also involved into the LSTM-based relationship as constraints. The proposed method is verified by the field data collected from the 6th Section of the Qingdao Metro Project, and the results reveal that the proposed LSTM-based method is accurate and acceptable.

Ink Landscape - Tea Set Design

Zhenxing Wang,Yuhang Jiang 한국디자인학회 2020 한국디자인학회 국제초대전도록 Vol.2020 No.11

An Accurate Isotope Dilution Liquid Chromatography-Tandem Mass Spectrometry Method for Serum C-Peptide and Its Use in Harmonization in China

Deng Yuhang,Zhang Chao,Wang Jing,Zeng Jie,Zhang Jiangtao,Zhang Tianjiao,Zhao Haijian,Zhou Weiyan,Zhang Chuanbao 대한진단검사의학회 2023 Annals of Laboratory Medicine Vol.43 No.4

Background: Serum C-peptide results from various routine methods used in China are highly variable, warranting well-performing methods to serve as an accuracy base to improve the harmonization of C-peptide measurements in China. We developed an accurate isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC–MS/MS) method for serum C-peptide measurement and explored its use in harmonization. Methods: After protein precipitation with ZnSO4 solution, C-peptide was extracted from serum samples by anion-exchange solid-phase extraction and quantified by ID-LC–MS/MS in positive ion mode. The precision and analytical recovery of the ID-LC–MS/MS method were assessed. Seventy-six serum samples were analyzed using the ID-LC–MS/MS method and six routine immunoassays. Ordinary linear regression (OLR) and Bland-Altman (BA) analyses were conducted to evaluate the relationship between the ID-LC–MS/MS method and routine immunoassays. Five serum pool samples assigned using the ID-LC–MS/MS method were used to recalibrate the routine assays. OLR and BA analyses were re-conducted after recalibration. Results: The within-run, between-run, and total precision for the ID-LC–MS/MS method at four concentrations were 1.0%–2.1%, 0.6%–1.2%, and 1.3%–2.2%, respectively. The analytical recoveries for the ID-LC–MS/MS method at three concentrations were 100.3%–100.7%, 100.4%–101.0%, and 99.6%–100.7%. The developed method and the immunoassays were strongly correlated, with all R2 >0.98. The comparability among the immunoassays was substantially improved after recalibration. Conclusions: The performance of the ID-LC–MS/MS method was carefully validated, and this method can be used to improve the harmonization of serum C-peptide measurements in China.

Design of Integer Chaotic Key Generator for Wireless Sensor Network

Juan Wang,Taiheng Yang,Yuhang Li,Qun Ding 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.11

In the block encryption algorithm of wireless sensor network, the chaotic map is used as a key generator conform to the application requirements of security and efficiency. Due to the one-dimensional discrete chaotic map would appear the degradation of dynamic characteristics after integer quantization, the cascaded and disturbed integer chaotic key generator were constructed in view of the ideas of cascade and disturbance. The performances of dynamic characteristics and statistical randomness were simulated and analyzed for the cascaded and disturbed integer chaotic sequences, and the disturbed integer chaotic sequence whose disturbance position for 1-8 bits was proved to be more excellent, and it can not only meet the encryption requirements of wireless sensor network, but also reduce the computing power and hardware resources overhead of the processor.

Assessment of Secondary Organic Carbon in the Southeastern United States: A Review

Lee, Sangil,Wang, Yuhang,Rusell, Armistead G. Informa UK (Taylor Francis) 2010 Journal of the Air & Waste Management Association Vol.60 No.11

Cold-induced ginsenosides accumulation is associated with the alteration in DNA methylation and relative gene expression in perennial American ginseng (Panax quinquefolius L.) along with its plant growth and development process

Mengzhen Hao,Yuhang Zhou,Jinhui Zhou,Min Zhang,Kangjiao Yan,Sheng Jiang,Wenshui Wang,Xiaoping Peng,San Zhou 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.5

Background: Ginsenosides accumulation responses to temperature are critical to quality formation in cold-dependent American ginseng. However, the studies on cold requirement mechanism relevant to ginsenosides have been limited in this species. Methods: Two experiments were carried out: one was a multivariate linear regression analysis between the ginsenosides accumulation and the environmental conditions of American ginseng from different sites of China and the other was a synchronous determination of ginsenosides accumulation, overall DNA methylation, and relative gene expression in different tissues during different developmental stages of American ginseng after experiencing different cold exposure duration treatments. Results: Results showed that the variation of the contents as well as the yields of total and individual ginsenosides Rg1, Re, and Rb1 in the roots were closely associated with environmental temperature conditions which implied that the cold environment plays a decisive role in the ginsenoside accumulation of American ginseng. Further results showed that there is a cyclically reversible dynamism between methylation and demethylation of DNA in the perennial American ginseng in response to temperature seasonality. And sufficient cold exposure duration in winter caused sufficient DNA demethylation in tender leaves in early spring and then accompanied the high expression of flowering gene PqFT in flowering stages and ginsenosides biosynthesis gene PqDDS in green berry stages successively, and finally, maximum ginsenosides accumulation occurred in the roots of American ginseng. Conclusion: We, therefore, hypothesized that cold-induced DNA methylation changes might regulate relative gene expression involving both plant development and plant secondary metabolites in such cold-dependent perennial plant species.

Transition metal modified manganese-based catalysts for soot oxidation promoted by noncompetitive adsorption of oxygen: Experiments and DFT calculations

Congcong Li,Ruiqi Li,Yuhang Wang,Runhan Niu,Qilong Guo,Changsen Zhang 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.126 No.-

A series of manganese-based oxide catalysts were synthesized by the hydrothermal method. By adjustingthe doping amounts of W and Cu in the system to study the catalytic performance of transition metaldopedmanganese oxides on soot combustion. They were deeply studied through various characterizationsand theoretical calculations. The results show that Wand Cu doping modifications can significantlyimprove the activity of manganese-based oxides in soot oxidation. W-Cu0.1/MnOx prepared by comodificationofWand Cu at 395 C can convert 90% of soot into CO2. The multiple characterization resultsshow that by adjusting the doping amount of copper and tungsten, the nano-flower-like morphology canbe obtained and the crystal plane can be reconstructed, which is helpful to increase the specific surfacearea, Mn3+ content, and oxygen vacancy content. The theoretical calculation results show that the oxygenvacancy on the surface of the catalyst shows the ability to activate O2 and H2O, and they show noncompetitiveadsorption. In addition, W-Cu0.1/MnOx has a good application prospect in the catalytic oxidationof soot because of its excellent catalytic stability. This work provides a reference for the designand preparation of non-noble metal-based catalysts for the elimination of soot particles from dieselengine exhaust.

Rutin alleviated lipopolysaccharide-induced damage in goat rumen epithelial cells

Zhan Jinshun,Gu Zhiyong,Wang Haibo,Liu Yuhang,Wu Yanping,Huo Junhong 아세아·태평양축산학회 2024 Animal Bioscience Vol.37 No.2

Objective: Rutin, also called vitamin P, is a flavonoids from plants. Previous studies have indicated that rutin can alleviate the injury of tissues and cells by inhibiting oxidative stress and ameliorating inflammation. There is no report on the protective effects of rutin on goat rumen epithelial cells (GRECs) at present. Hence, we investigated whether rutin can alleviate lipopolysaccharide (LPS)-induced damage in GRECs. Methods: GRECs were cultured in basal medium or basal medium containing 1 μg/mL LPS, or 1 μg/mL LPS and 20 μg/mL rutin. Six replicates were performed for each group. After 3-h culture, the GRECs were harvested to detect the relevant parameters. Results: Rutin significantly enhanced the cell activity (p<0.05) and transepithelial electrical resistance (TEER) (p<0.01) and significantly reduced the apoptosis rate (p<0.05) of LPSinduced GRECs. Rutin significantly increased superoxide dismutase, glutathione peroxidase, and catalase activity (p<0.01) and significantly decreased lactate dehydrogenase activity and reactive oxygen species and malondialdehyde (MDA) levels in LPS-induced GRECs (p<0.01). The mRNA and protein levels of interleukin 6 (IL-6), IL-1β, and C-X-C motif chemokine ligand 8 (CXCL8) and the mRNA level of tumor necrosis factor-α (TNF-α) and chemokine C-C motif ligand 5 (CCL5) were significantly increased in LPS-induced GRECs (p<0.05 or p<0.01), while rutin supplementation significantly decreased the mRNA and protein levels of IL-6, TNF-α, and CXCL8 in LPS-induced GRECs (p<0.05 or p<0.01). The mRNA level of toll-like receptor 2 (TLR2), and the mRNA and protein levels of TLR4 and nuclear factor κB (NF-κB) was significantly improved in LPS-induced GRECs (p<0.05 or p<0.01), whereas rutin supplementation could significantly reduce the mRNA and protein levels of TLR4 (p<0.05 or p<0.01). In addition, rutin had a tendency of decreasing the protein levels of CXCL6, NF-κB, and inhibitor of nuclear factor kappa-B alpha (0.05< p<0.10). Rutin could significantly decreased interferon regulatory factor 3 mRNA expression in LPS-induced GRECs (p<0.05), whereas interferon induced protein with tetratricopeptide repeats 3 (IFIT3) and toll-interacting protein (TOLLIP) mRNA expression was not significantly different between the groups. LPS reduced the tight junction protein zonula occludin 1 (ZO-1) level in GRECs whereas rutin enhanced it. Rutin significantly improved tight junction protein Claudin-1 mRNA expression in LPS-induced GRECs (p<0.01), but could not affect tight junction protein Occludin mRNA expression. Conclusion: Rutin alleviated LPS-induced barrier damage in GRECs by improving oxidation resistance and anti-inflammatory activity, which may be related to TLR/NF-κB signaling pathway inhibition.

Extended Gate Field Effect Transistor Using GaN/Si Hybrids Nanostructures for pH Sensor

Manchen Zhang,Ruzhi Wang,Zhen Shen,Yuhang Ji 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.9

The pH sensor of an extended gate field effect transistor (EGFET) with gallium nitride/silicon hybrid nanostructure is fabricated and analyzed. Si nanowires (NWs) are fabricated via the Ag-assisted electroless etching technique and are then covered by GaN NWs through plasma-enhanced chemical vapor deposition (PECVD). The GaN nanostructure is synthesized by introducing gallium oxide (Ga2O3) and nitrogen (N2) for the growth of NWs. The GaN nanowires supply a larger surface area than that of the pristine Si NWs, where there is a better sensitivity for pH sensor. The GaN/Silicon hybrid sensors exhibit a sensitivity higher (50.4 mV/pH) than that of pristine Si NWs sensors (41.2 mV/pH). This GaN/Si hybrid pH sensor prepared by simple and low-cost method may be potentially applied for cheap biosensor devices.