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Comparative study on transport properties of N-, P-, and As-doped SiC nanowires: Calculated based on first principles

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Chinese Physics B 2020年第3期29卷 369-374页

作者： ya-lin li Pei Gong Xiao-Yong Fang Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China

According to the one-dimensional quantum state distribution, carrier scattering, and fixed range hopping model, the structural stability and electron transport properties of N-, P-, and As-doped SiC nanowires(N-SiCNWs, P-SiCNWs, and As-SiCNWs) are simulated by using the first principles calculations. The results show that the lattice structure of NSiCNWs is the most stable in the lattice structures of the above three kinds of doped SiCNWs. At room temperature,for unpassivated SiCNWs, the doping effect of P and As are better than that of N. After passivation, the conductivities of all doped SiCNWs increase by approximately two orders of magnitude. The N-SiCNW has the lowest conductivity. In addition, the N-, P-, As-doped SiCNWs before and after passivation have the same conductivity–temperature characteristics,that is, above room temperature, the conductivity values of the doped SiCNWs all increase with temperature *** results contribute to the electronic application of nanodevices.

关键词： N-,P-,As-doped SiC nanowires transport properties first-principles theory

First Principle Study on Optical Properties of Tri-Group Doped(6,6) SiC Nanotubes

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Chinese Physics Letters 2018年第11期35卷 80-82页

作者： Pei GONG ya-lin li ya-Hui JIA Xiao-Yong FANG Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan University

The optical properties of tri-group（B, Al, Ga, In） doped（6,6） SiC nanotubes（SiCNTs） are studied from first principles. The results show that the main absorption and dispersion of SiCNTs caused by the intrinsic transition appear in the ultraviolet-visible region（below 500 nm）, and the tri-group doping increases the minimum dielectric constant value resulting in enhanced transmittance. In addition, the tri-group doping can introduce a weak absorption and dispersion region in the near-mid-infrared region, and the response peak blue shifts as the diameter of the doping atom increases. Comparative studies of reflectance, absorptivity, and transmittance show that the key factors affecting the transmittance of SiCNTs are reflectance（or refractive index） rather than absorption coefficient.

关键词： Ga Al Ts First Principle Study on Optical Properties of Tri-Group Doped SiC Nanotubes

Conductance and dielectric properties of hydrogen and hydroxyl passivated SiCNWs

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Chinese Physics B 2021年第10期30卷 609-616页

作者： Wan-Duo Ma ya-lin li Pei Gong ya-Hui Jia Xiao-Yong Fang Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China

Based on the transport theory and the polarization relaxation model,the effects of hydrogen and hydroxyl passivation on the conductivity and dielectric properties of silicon carbide nanowires(SiCNWs)with different sizes are numerically *** results show that the variation trend of conductivity and band gap of passivated SiCNWs are opposite to the scenario of the size effect of bare *** the influencing factors of conductivity,the carrier concentration plays a leading *** the dielectric properties,the bare SiCNWs have a strong dielectric response in the blue light region,while passivated SiCNWs show a more obvious dielectric response in the far ultraviolet-light *** particular,hydroxyl passivation produces a strong dielectric relaxation in the microwave band,indicating that hydroxyl passivated SiCNWs have a wide range of applications in electromagnetic absorption and shielding.

关键词： silicon carbide nanowires passivation conductance properties dielectric relaxation

Expression and functional characterization of platelet-derived growth factor receptor-like gene

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World Journal of Gastroenterology 2010年第12期16卷 1465-1472页

作者： Guo, Feng-Jie Zhang, Wei-Jia li, ya-lin liu, yan li, Yue-Hui Huang, Jian Wang, Jia-Jia Xie, Ping-li li, Guan-Cheng Cent S Univ Xiangya Sch Med Canc Res Inst Changsha 410078 Hunan Peoples R China

AIM:To investigate the role of platelet-derived growth factor receptor-like gene(PDGFRL)in the anti-cancer therapy for colorectal cancers(CRC).METHODS:PDGFRL mRNA and protein levels were measured by reverse transcription-polymerase chain reaction(RT-PCR)and immunohistochemistry in CRC and colorectal normal *** prokaryotic expression vector was carried out in Escherichia coli(***),and purified by immobilized metal affinity *** effect of PDGFRL protein on CRC HCT-116 cells was detected by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide(MTT),clone counting,cell cycle,and wound healing ***:Both RT-PCR and immunohistochemistry showed that the expression of PDGFRL in colorectal normal tissues was higher than in cancer *** pET22b-PDGFRL prokaryotic expression vector was successfully expressed in ***,and the target protein was expressed in the form of inclusion *** purification and refolding,recombinant human PDGFRL(rhPDGFRL)could efficiently inhibit the proliferation and invasion of CRC HCT-116 cells detected by MTT,clone counting and wound healing ***,rhPDGFRL arrested HCT-116 cell cycling at the G0/G1 ***:PDGFRL is a potential gene for application in the anti-cancer therapy for CRC.

关键词： Platelet-derived growth factor receptorlike Colorectal cancer Prokaryotic expression Reverse transcription-polymerase chain reaction Immunohistochemistry

Polarization Mechanism of Oxygen Vacancy and Its Influence on Dielectric Properties in ZnO

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Chinese Physics Letters 2011年第2期28卷 179-182页

作者： WANG li-Na FANG Xiao-Yong HOU Zhi-ling li ya-lin WANG Kun YUAN Jie CAO Mao-Sheng School of Science Yanshan UniversityQinhuangdao 066004 School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081 School of Information Engineering Central University for NationalitiesBeijing 100081

We report on the mechanism of the dielectric properties of oxygen vacancy in ZnO,using ab initio numerical simulations of oxygen vacancy on the band structure and dielectric properties,to develop photoelectric material *** is revealed that the appearance of oxygen vacancies leads to wider energy band gap,obvious blue shift and increase in the peak of dielectric function as compared to the intrinsic ZnO *** explain these unusual phenomena and analyze the dielectric changes with the mechanism of polarization in the *** is shown that the main mechanism of influencing dielectric properties is the electron displacement *** result may be helpful for development of photoelectric materials.

关键词： materials dielectric vacancy

Dilated intercellular spaces in gastroesophageal reflux disease patients and the changes of intercellular spaces after omeprazole treatment

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Chinese Medical Journal 2008年第14期121卷 1297-1301页

作者： XUE yan ZHOU li-ya lin San-ren Department of Gastroenterology Peking University Third Hospital Beijing 100083 China

Background Gastroesophageal reflux disease （GERD） is a common disorder. Dilation of intercellular spaces of esophageal epithelium has been revealed at transmission electron microscopy both in the rabbit acid-perfused esophagus and in esophageal biopsies from GERD patients. This study aimed to observe the changes of the intercellular spaces of squamous epithelium of lower esophagus in patients with GERD and the changes of intercellular spaces of patients with erosive esophagitis （EE） before and after omeprazole treatment. Methods Outpatients having GERD symptoms for more than 3 months and volunteers were collected. All of them underwent gastroendoscopy and 24-hour ambulatory pH monitoring. Biopsies were taken from the lower esophagus （2 cm above Z-line） for electron microscope examination. Five healthy volunteers, six non-erosive reflux disease （NERD） patients, and five EE patients were enrolled. Intercellular spaces of GERD patients and controls were calculated. Then we selected 20 patients with EE diagnosed by gastroendoscopy. All of them were treated with omeprazole （Losec, 20 mg bid） for 4 weeks then underwent gastroendoscopy again. Biopsies were taken from 2 cm above Z-line for electron microscope examination. All the patients completed the questionnaire about reflux symptoms before and after treatment. Results Intercellular spaces of esophageal epithelial cell in volunteers, NERD patients and EE patients were （0.37±0.07）μm, （1.31±0.08）μm, and （1.33±0.14）μm, respectively, with significant differences between the control group and the NERD group （P=0.000）. In the 20 EE patients, the mean intercellular space before treatment was （1.14±0.15） μm After treatment the intercellular space was （0.51±0.18）μm, a significant difference compared with pre-treatment measurements （P=0.000）. Conclusions Dilated intercellular spaces （DIS） were seen in both NERD and EE cases. The dilated intercellular spaces of esophaaeal epithelium in EE patients could be recovered after a sh

关键词： gastro-esophageal reflux disease electron microscope dilated intercellular spaces omeprazole

Inhibition of Obtusifolin on retinal pigment epithelial cell growth under hypoxia

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International Journal of Ophthalmology(English edition) 2019年第10期12卷 1539-1547页

作者： li-Fei Wang Zhong-yang yan ya-lin li yan-Hui Wang Sheng-Juan Zhang Xin Jia Lu Lu yan-Xia Shang Xin Wang Yun-Huan li Shan-Yu li Fundus Surgery Ward Hebei Provincial Eye HospitalXingtai054001Hebei ProvinceChina Diabetic Eye Disease Ward Hebei Provincial Eye HospitalXingtai054001Hebei ProvinceChina Corneal Disease Ward Hebei Provincial Eye HospitalXingtai054001Hebei ProvinceChina

AIM: To explore the effect of Obtusifolin on retinal pigment epithelial cell growth under ***: In vitro chemical hypoxia model of ARPE-19 cells was established using cobalt chloride(CoCl2). Cell viability was tested by cell counting kit-8(CCK-8) assay. Western blot and real-time quantitative polymerase chain reaction were applied to detect proteins and mRNAs respectively. Flow cytometry was used to examine the cell cycle. Secretion of vascular endothelial growth factor(VEGF) was tested by using enzyme linked immunosorbent assay(EliSA).RESULTS: Under the chemical hypoxia model established by CoCl2, hypoxia inducible factor-1α(HIF-1α) mRNA and protein levels was up-regulated. Cell viability was increased and the proportion of S phase was higher. Obtusifolin could reduce cell viability under hypoxic conditions and arrest cells in G1 phase. Obtusifolin reduced the expression of Cyclin D1 and proliferating cell nuclear antigen(PCNA) in the hypoxic environment and increased the expression of p53 and p21. The levels of VEGF, VEGFR2 and eNOS proteins and mRNA were significantly increased under hypoxia while Obtusifolin inhibited the ***: Obtusifolin can inhibit cell growth under hypoxic conditions and down-regulate HIF-1/VEGF/eNOS secretions in ARPE-19 cells.

关键词： retinal pigment epithelial cells Obtusifolin vascular endothelial growth factor hypoxia

Research and application of spectral inversion technique in frequency domain to improve resolution of converted PS-wave

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Applied Geophysics 2017年第2期14卷 247-257,323页

作者： Zhang Hua He Zhen-Hua li ya-lin li Rui He Guamg-Ming li Zhong State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu 610059 China College of Geophysics Chengdu University of Technology Chengdu 610059 China Geophysical Exploration Company Chuanqing Drilling Engineering Co.Ltd. CNPC Chengdu 610213 China Mountain Geophysical Technology Test Center CNPC Chengdu 610213 China

Multi-wave exploration is an effective means for improving precision in the exploration and development of complex oil and gas reservoirs that are dense and have low permeability. However, convened wave data is characterized by a low signal-to-noise ratio and low resolution, because the conventional deconvolution technology is easily affected by the frequency range limits, and there is limited scope for improving its resolution. The spectral inversion techniques is used to identify λ/8 thin layers and its breakthrough regarding band range limits has greatly improved the seismic resolution. The difficulty associated with this technology is how to use the stable inversion algorithm to obtain a high-precision reflection coefficient, and then to use this reflection coefficient to reconstruct broadband data for processing. In this paper, we focus on how to improve the vertical resolution of the converted PS-wave for multi-wave data processing. Based on previous research, we propose a least squares inversion algorithm with a total variation constraint, in which we uses the total variance as a priori information to solve under-determined problems, thereby improving the accuracy and stability of the inversion. Here, we simulate the Gaussian fitting amplitude spectrum to obtain broadband wavelet data, which we then process to obtain a higher resolution converted wave. We successfully apply the proposed inversion technology in the processing of high-resolution data from the Penglai region to obtain higher resolution convened wave data, which we then verify in a theoretical test. Improving the resolution of converted PS-wave data will provide more accurate data for subsequent velocity inversion and the extraction of reservoir reflection information.

关键词： spectral inversion resolution broadband wavelet thin reservoir

北羌塘托纳木地区上白垩统阿布山组沉积特征、物源分析及其构造意义

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地球学报 2022年第4期43卷 555-568,I0001-I0005页

作者：杜林涛李亚林中国地质大学(北京)地球科学与资源院北京100083

羌塘—拉萨碰撞造山作用是青藏高原中生代最为重要的构造事件,羌塘盆地内晚白垩世阿布山组是羌塘—拉萨碰撞造山作用的沉积记录。托纳木地区发育了北羌塘坳陷少有的晚白垩世阿布山组沉积,然而对其形成构造背景和动力学机制尚不清楚。本... 详细信息

羌塘—拉萨碰撞造山作用是青藏高原中生代最为重要的构造事件,羌塘盆地内晚白垩世阿布山组是羌塘—拉萨碰撞造山作用的沉积记录。托纳木地区发育了北羌塘坳陷少有的晚白垩世阿布山组沉积,然而对其形成构造背景和动力学机制尚不清楚。本文通过对托纳木地区阿布山组沉积环境、物源区详细表明,该地区阿布山组下部以冲积扇环境为主,中上部为辫状河环境。砾石成分、古水流、砂岩岩石学、砂岩重矿物、碎屑锆石U-Pb定年等物源综合分析显示中央隆起带和盆地内部均为阿布山组提供物源,结合邻区阿布山组对比,认为研究区物源来自盆地内西南方向下伏沉积、晚三叠世那底冈日组火山岩以及盆地基底,阿布山组沉积受盆地内构造控制。托纳木地区阿布山组物源区特征反映了北羌塘晚白垩世地体内部的逆冲事件,与羌塘—拉萨地体碰撞有关。

关键词：晚白垩世羌塘盆地沉积物源构造意义