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Ionospheric vertical total electron content prediction model in low-latitude regions based on long short-term memory neural network

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Chinese Physics B 2022年第8期31卷 347-358页

作者： Tong-Bao Zhang hui-jian liang Shi-Guang Wang Chen-Guang Ouyang Department of Precision Instrument Tsinghua UniversityBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instrument Tsinghua UniversityBeijing 100084China Department of Electronic Engineer Tsinghua UniversityBeijing 100084China

Ionosphere delay is one of the main sources of noise affecting global navigation satellite systems, operation of radio detection and ranging systems and very-long-baseline-interferometry. One of the most important and common methods to reduce this phase delay is to establish accurate nowcasting and forecasting ionospheric total electron content models. For forecasting models, compared to mid-to-high latitudes, at low latitudes, an active ionosphere leads to extreme differences between long-term prediction models and the actual state of the ionosphere. To solve the problem of low accuracy for long-term prediction models at low latitudes, this article provides a low-latitude, long-term ionospheric prediction model based on a multi-input-multi-output, long-short-term memory neural network. To verify the feasibility of the model, we first made predictions of the vertical total electron content data 24 and 48 hours in advance for each day of July 2020 and then compared both the predictions corresponding to a given day, for all days. Furthermore, in the model modification part, we selected historical data from June 2020 for the validation set, determined a large offset from the results that were predicted to be active, and used the ratio of the mean absolute error of the detected results to that of the predicted results as a correction coefficient to modify our multi-input-multi-output long short-term memory model. The average root mean square error of the 24-hour-advance predictions of our modified model was 4.4 TECU, which was lower and better than5.1 TECU of the multi-input-multi-output, long short-term memory model and 5.9 TECU of the IRI-2016 model.

关键词： long-short-term memory neural network equatorial ionosphere vertical total electron content vertical total electron content(vTEC)

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Real-time frequency transfer system over ground-to-satellite link based on carrier-phase compensation at 10-16 level

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Chinese Physics B 2021年第8期30卷 260-268页

作者： hui-jian liang Shi-Guang Wang Yu Bai Si-Chen Sun Li-Jun Wang Department of Electronic Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua UniversityBeijing 100084China Department of Precision Instruments Tsinghua UniversityBeijing 100084China Department of Physics Tsinghua UniversityBeijing 100084China

We demonstrate a novel and stable frequency transfer scheme over ground-to-satellite link based on real-time carrier-phase detection and *** performed a zero-baseline measurement with the designed system,an uninterrupted frequency standard signal is recovered in the reception station without additional post-correction of delay error caused in the route,which is because the phase error of the entire route is tracked and compensated continuously in *** achieve this goal,we employed two carriers in the system and the differential signal is transferred in order to eliminate the instability results from the local oscillator at the satellite transponder as well as the common-mode noise induced in the transfer route and microwave *** stability of 3×10^(-16) with an integration time of 1 day was achieved and the time fluctuation during one day was measured to be about±20 *** sources and possible solutions are *** zero-baseline method shows a promising result for real-time satellite-based time and frequency transfer and deserves further research to find whether it works between long-baseline stations.

关键词： frequency transfer ground-to-satellite link carrier-phase compensation

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Interface interaction between SiO_(2) and magnetite under high temperature:particle migration and inhibition mechanism

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Journal of Iron and Steel Research International 2024年第3期31卷 561-572页

作者： Yao-zu Wang jian-liang Zhang Qiang Cheng hui-qing jiang Zheng-jian Liu Yu-bo Tan School of Intelligent Science and Technology University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Advanced Engineering University of Science and Technology BeijingBeijing 100083China

Silicon is one of the main gangue components in iron ore,usually in the form of quartz and *** studies have shown that SiO_(2) has a two-sided effect on the consolidation of pellets during high-temperature oxidation roasting of ***,it is very difficult to capture the structural evolution and migration mechanisms during high-tem-perature roasting process by existing experimental ***,the influence of SiO_(2) on the consolidation behavior of magnetite was studied through a series of roasting experiments and molecular dynamic *** results show that the consolidation index and particle growth index decrease with the increase in SiO_(2) content in the *** 1573 K,the liquid phase promotes the recrystallization growth of hematite at high *** dynamic study shows that it is difficult for quartz SiO_(2) to form sintering neck with Fe_(2)O_(3).When the calcination temperature is higher than 1400 K,the Fe_(2)O_(3)-Fe_(2)SiO_(4) system produces a considerable sintering neck structure after *** atomic migration ability of Fe_(2)SiO_(4) is much higher than that of Fe_(2)O_(3).The higher atomic migration ability of Fe_(2)SiO_(4) is the main reason for the formation of the sintering neck.

关键词： Sintering neck Crystal growth Consolidation Molecular dynamics SiO_(2)

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O_(2) adsorption on Fe_(3)O_(4) (110) surface and effect of gangue element Al doping: combined study of binding experiment and ab initio molecular dynamics

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Journal of Iron and Steel Research International 2024年第4期31卷 810-827页

作者： Zheng-jian Liu hui-qing jiang Yao-zu Wang jian-liang Zhang Hong-mei Qiao An-yang Zheng Fang-yu Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Beijing Shougang Co. Ltd.Qian'an 064404HebeiChina Department of Physics National University of Defense TechnologyChangsha 410128HunanChina

At high temperature,the chemical reaction mechanism at the interface of magnetite and the influence mechanism of gangue element Al on the oxidation performance of magnetite are not *** addition,due to the limitation of existing experimental equipment,it is difficult to clarify the interface reaction mechanism in the oxidation process and the influence mechanism of Al on the surface oxidation reaction of Fe_(3)O_(4) at an atomic scale at high *** surface oxidation reaction mechanism of magnetite and the influence mechanism of Al on the oxidation of magnetite were studied by experiments and AIMD(ab initio molecular dynamics).The experimental results show that the existence of Al_(2)O_(3) will reduce the initial oxidation temperature and comprehensive oxidation performance of *** AIMD results show that aluminum can accelerate the interface reaction rate of Fe_(3)O_(4) in the high-temperature oxidation atmosphere,but the strong Al-O binding ability is not conducive to the transfer of O atoms in the oxidation process.

关键词： Ironmaking Magnetite oxidation Interface reaction Adsorption-Gangue aluminum AIMD

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Sutureless Intestinal Anastomosis with a Novel Device of Magnetic Compression Anastomosis

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Chinese Medical Sciences Journal 2011年第3期26卷 182-189页

作者： Chao Fan Jia Ma Hong-ke Zhang Rui Gao jian-hui Li liang Yu Zheng Wu Yi Lv Department of Hepatobiliary Surgery the First Affiliated HospitalMedical School of Xi＇an Jiaotong UniversityXi＇an 710061China

Objective To explore the feasibility and efficiency of a novel magnetic compression anastomats(MCAs) in intestinal *** A total of 36 male mongrel canines underwent intestinal anastomosis using traditional hand-sewn(n=18) or a novel MCAs(n=18).We compared the anastomosis time,postoperative complications,bursting strength of anastomoses,gross appearance,and pathology between two groups at each time-point of *** The mean anastomosis time with MCAs was significantly less than that with hand-sewn(8.50±1.95 vs.31.1±4.32 minutes,P<0.001).The blood stools and intussusceptions occurred in both groups during follow-up *** 1 mongrel canine receiving intestinal anastomosis by MCAs experienced anastomotic *** average bursting pressure of anastomoses obtained from mongrel canines undergoing intestinal anastomosis by MCAs was significantly higher than that by traditional hand-sewn at 1 week's follow-up time(P<0.05).Gross appearance of the anastomoses constructed by MCAs was relatively smoother and *** evalution of anastomoses revealed that general inflammation was greater in hand-sewn anastomoses than magnetic *** The magnetic compression anastomat is a safe and effective device of sutureless intestinal anastomosis in canine models.

关键词： magnetic compression anastomosis bursting strength foreign body reaction

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Effects of protein synthesis inhibitors on the behavioral sensitization induced by a single morphine exposure in mice

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中国药理通讯 2008年第3期25卷 40-41页

作者： Juan Luo jian-hui liang Department of Neuropharmacology National Institute on Drug Dependence Peking University 38 Xueyuan Road Beijing 100191 PR China

Repeated exposure to psychoactive substance causes persistent behavioral sensitization and protein synthesis in brain, which is thought to play an important role in certain aspects of drug addiction。The present study was designed to evaluate whether long-lasting behavioral sensitization would also be evoked by a single exposure to morphine。Mice pretreated once with morphine (20mg/kg, intraperitoneal (i。p。)) and challenged with the lower dose (5mg/kg, i。p。) after 4, 7, 21 days, but not i, 2, 3 days of washout showed increased locomotor activity。

关键词：蛋白质分析方法致敏作用吗啡药物

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Magnesium-containing pellet regulating blast furnace ferrous burden interaction:softening-melting behavior and mechanism

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Journal of Iron and Steel Research International 2024年第7期31卷 1623-1635页

作者： Li-ming Ma jian-liang Zhang Yao-zu Wang Xiao-yong Ma Gui-lin Wang Zhuo Li hui-qing jiang Zheng-jian Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Lingyuan Iron and Steel Group Co. Lingyuan 122500LiaoningChina

MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed ***-containing pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance *** the structure of the ferrous burden is magnesium-containing pellets mixed with low-MgO sinter,the magnesium-containing pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the composition of the slag phase and improve the slag *** the structure of the ferrous burden is magnesium-containing pellets mixed with high-MgO sinter,the magnesium-containing pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the content of the high melting point solid-phase particles in the slag,lead to an increase in the viscosity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge ***,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO content of the sinter to 1.96 wt.%,increasing the MgO content of the pellets to 1.03-1.30 wt.%,controlling the MgO/Al_(2)O_(3) ratio of the mixed burden within 1.15-1.32,narrowing the position of the cohesive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.

关键词： Ironmaking Ferrous burden Softening-melting property Interaction Permeability Slag

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Shi-pi-xiao-ji formula suppresses hepatocellular carcinoma by reducing cellular stiffness through upregulation of acetyl-coA acetyltransferase 1

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2727-2741页

作者： hui-Ying jian Zi-Cheng liang Huan Wen Zhen Zhang Pu-Hua Zeng Graduate School Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Hunan Provincial Hospital of Integrated Traditional Chinese and Western Cancer Research Institute of Hunan Academy of Traditional Chinese MedicineHunan Academy of Chinese MedicineChangsha 410006Hunan ProvinceChina

BACKGROUND Previous studies have shown that the Shi-pi-xiao-ji(SPXJ)herbal decoction formula is effective in suppressing hepatocellular carcinoma(HCC),but the underlying mechanisms are not ***,this study investigated whether the antitumor effects of the SPXJ formula in treating HCC were mediated by acetyl-coA acetyltransferase 1(ACAT1)-regulated cellular *** a series of experiments,we concluded that SPXJ inhibits the progression of HCC by upregulating the expression level of ACAT1,lowering the level of cholesterol in the cell membrane,and altering the cellular stiffness,which provides a new idea for the research of traditional Chinese medicine against *** To investigate the anti-tumor effects of the SPXJ formula on the malignant progression of *** HCC cells were cultured in vitro with SPXJ-containing serum prepared by injecting SPXJ formula into wild-type *** apoptotic rate and proliferative,invasive,and migratory abilities of control and SPXJ-treated HCC cells were *** force microscopy was used to determine the cell surface morphology and the Young’s modulus values of the control and SPXJ-treated HCC *** membrane cholesterol levels in HCC cells were detected using the Amplex Red cholesterol detection ***1 protein levels were estimated using western *** Compared with the vehicle group,SPXJ serum considerably reduced proliferation of HCC cells,increased stiffness and apoptosis of HCC cells,inhibited migration and invasion of HCC cells,decreased plasma membrane cholesterol levels,and upregulated ACAT1 protein ***,treatment of HCC cells with the water-soluble cholesterol promoted proliferation,migration,and invasion of HCC cells as well as decreased cell stiffness and plasma membrane cholesterol levels,but did not alter the apoptotic rate and ACAT1 protein expression levels compared with the vehicle *** SPXJ formula inhibited proliferation,invasion,and migration

关键词： Shi-pi-xiao-ji formula Hepatocellular carcinoma Cellular stiffness Plasma membrane cholesterol level AcetylcoA acetyltransferase 1

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Optimizing magnetoelastic properties by machine learning and high-throughput micromagnetic simulation

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Rare Metals 2024年第5期43卷 2251-2262页

作者： jian-Hu Gong Zheng-Ming Zhang Cheng-liang Zhang Peng-Qiang Hu Chao Zhou Dun-hui Wang Sen Yang Division of Microelectronic Materials and Devices Hangzhou Dianzi UniversityHangzhou 310018China School of Physics MOEKey Laboratory forNonequilibrium Synthesis and Modulation of Condensed Matter and State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an 710049China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing210093China

Magnetoelastic couplings in giant magnetostrictive materials(GMMs)attract significant interests due to their extensive applications in the fields of spintronics and energy harvesting *** the role of the selection of materials and the response to external fields is essential for attaining desired functionality of a ***,machine learning(ML)models are conducted to predict saturation magnetostrictions(λ_(s))in RFe_(2)-type(R=rare earth)GMMs with different *** to ML-predicted composition–λsrelations,it is discovered that the values ofλshigher than1100×10^(-6)are almost situated in the composition space surrounded by 0.26≤x≤0.60 and 1.90≤y≤2.00 for the ternary compounds of Tb_(x)Dy_(1-x)Fe_(y).Assisted by ML predictions,the compositions are further narrowed down to the space surrounded by 0.26≤x≤0.32 and 1.92≤y≤1.97 for the excellent piezomagnetic(PM)performance in the Tb_(x)Dy_(1-x)Fe_(y)based PM device through our developed high-throughput(HTP)micromagnetic simulation(MMS)***,high sensitivities up to10.22-13.61 m T·MPa^(-1)are observed in the optimized range within which the available experimental data fall *** work not only provides valuable insights toward understanding the mechanism of magnetoelastic couplings,but also paves the way for designing and optimizing highperformance magnetostrictive materials and PM sensing devices.

关键词： Magnetostriction Piezomagnetic effect Machine learning Micromagnetic simulation

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Processing of a low-costγ-γ'NiPtAl coating with improved oxidation resistance

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Rare Metals 2024年第6期43卷 2832-2841页

作者： Yan jiang liang-liang Wei jian He Hong-Bo Guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structural Materials and Protective Coatings Ministry of Industry and Information TechnologyBeihang UniversityBeijing 100191China

A novelγ-γ'(Ni solid solution—Ni_(3)Al)NiPtAl coating was produced on advanced single-crystal(SC)superalloy N5 by electroplating of a thin Pt coating with~3μm in thickness followed by heat treatment at 1000℃in *** comparison,a traditionalγ-γ'NiPtAl coating was also produced by electroplating of a thick Pt coating with~6μm in thickness followed by heat treatment at 1100℃in *** novel coating has a mass gain of~0.5 mg·cm^(-2)after 100 h 1-h cyclic oxidation at 1150℃,showing better oxidation resistance than the traditional *** oxide scale mostly consisting ofα-Al_(2)O_(3)grew on the novel coating because the element Cr from the SC alloy substrate contributes to the formation ofα-Al_(2)O_(3).Pt content in the novel coating has significant effect on the oxidation *** optimized Pt content in the coating is about 16 at%,which is helpful to reduce the diffusion of harmful elements from the substrate into the coating but also to reduce the cost of the coating.

关键词： γ-γ'NiPtAl coating Platinum Oxidation Al_(2)O_(3) Superalloy

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