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Serendipitous discovery of warm absorbers in the Seyfert 2 galaxy IRAS 18325-5926

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Research in Astronomy and Astrophysics 2011年第10期11卷 1171-1184页

作者： shui-Nai Zhang qiu-Sheng Gu Li Ji Zhi-Xin Peng Department of Astronomy Nanjing University Nanjing 210093 China Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry ofEducation Nanjing 210093 China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory ChineseAcademy of Sciences Nanjing 210008 China

Warm absorption is a common phenomenon in Seyfert 1 s and quasars, but is rare in Seyfert 2s. We report the detection of warm absorbers with high energy resolution in the Seyfert 2 galaxy IRAS 18325-5926 for the first time with Chandra HETGS spectra. An intrinsic absorbing line system with an outflow velocity - 400 km s^-1 was found, which is contributed by two warm absorbers with FWHM of 570 km s^-1 and 1360 km s^-1, respectively. The two absorbers were adjacent, and moving transversely across our line of sight. We constrained the distance between the center and the absorbers to be a small value, suggesting that the absorbers may originate from the highly ionized accretion disk wind ejected five years ago. The perspective of this type 2 Seyfert provides the best situation in which to investigate the vertical part of the funnel-like outflows. Another weak absorbing line system with zero redshift was also detected, which could be due to Galactic absorption with very high temperature or an intrinsic outflow with a very high velocity - 6000 km s^-1.

关键词： galaxies Seyfert -- galaxies absorption lines -- X-rays galaxies -- galaxies individual IRAS 18325-5926

Spatial-temporal Analysis and Prediction of Precipitation Extremes: A Case Study in the Weihe River Basin, China

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Chinese Geographical Science 2022年第2期32卷 358-372页

作者： qiu Dexun WU Changxue mu Xingmin ZHAO Guangju GAO Peng State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest Agriculture and Forestry UniversityYangling 712100China

Extreme precipitation events bring considerable risks to the natural ecosystem and human *** the spatial-temporal characteristics of extreme precipitation and predicting it quantitatively are critical for the flood prevention and water resources planning and *** this study,daily precipitation data(1957–2019)were collected from 24 meteorological stations in the Weihe River Basin(WRB),Northwest China and its surrounding *** first analyzed the spatial-temporal change of precipitation extremes in the WRB based on space-time cube(STC),and then predicted precipitation extremes using long short-term memory(LSTM)network,auto-regressive integrated moving average(ARIMA),and hybrid ensemble empirical mode decomposition(EEMD)-LSTM-ARIMA *** precipitation extremes increased as the spatial variation from northwest to southeast of the *** were two clusters for each extreme precipitation index,which were distributed in the northwestern and southeastern or northern and southern of the *** precipitation extremes in the WRB present a strong clustering ***,the pattern of only high-high cluster and only low-low cluster were primarily located in lower reaches and upper reaches of the WRB,*** spots(25.00%–50.00%)were more than cold spots(4.17%–25.00%)in the *** spots were mainly concentrated in the northwestern part,while hot spots were mostly located in the eastern and southern *** different extreme precipitation indices,the performances of the different models were *** accuracy ranking was EEMD-LSTM-ARIMA>LSTM>ARIMA in predicting simple daily intensity index(SDII)and consecutive wet days(CWD),while the accuracy ranking was LSTM>EEMD-LSTM-ARIMA>ARIMA in predicting very wet days(R95 P).The hybrid EEMD-LSTM-ARIMA model proposed was generally superior to single models in the prediction of precipitation extremes.

关键词： precipitation extremes space-time cube(STC) ensemble empirical mode decomposition(EEMD) long short-term memory(LSTM) auto-regressive integrated moving average(ARIMA) Weihe River Basin,China

BOUNDEDNESS AND ASYMPTOTIC STABILITY IN A PREDATOR-PREY CHEMOTAXIS SYSTEM WITH INDIRECT PURSUIT-EVASION DYNAMICS

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Acta Mathematica Scientia 2022年第3期42卷 1035-1057页

作者： Shuyan qiu Chunlai mu Hong YI School of Sciences Southwest Petroleum UniversityChengdu 610500China College of Mathematics and Statistics Chongqing UniversityChongqing 401331China School of Mathematics and Statistics Chongqing Technology and Business UniversityChongqing 400067China

This work explores the predator-prey chemotaxis system with two chemicals {u_(t) = Δu + ∇ ・ (u∇v) + μ_(1)u(1 − u − α_(1)w), x ∈ Ω, t > 0,v_(t )= Δv −α_(1)v + β_(1)w, x ∈ Ω, t > 0,w_(t) = Δw − ξ∇ ・ (w∇z) + μ_(2)w(1 + α_(2)u − w), x ∈ Ω, t > 0,z_(t) =Δz −α_(2)z +β_(2)u, x ∈ Ω, t > 0, in an arbitrary smooth bounded domainΩ■R^(n) under homogeneous Neumann boundary *** parameters in the system are *** first prove that if n≤3,the corresponding initial-boundary value problem admits a unique global bounded classical solution,under the assumption thatχ,ξ,μ_(i),a_(i),α_(i) andβ_(i)(i=1,2)satisfy some suitable ***,we also analyse the asymptotic behavior of solutions to the above system and show that·when a_(1)1 andμ_(2)/ξ_(2) is sufficiently large,the global bounded classical solution(u,v,w,z)of this system exponentially converges to(0,α_(1)/β_(1),1,0)as t→∞;·when a1=1 andμ_(2)/ξ_(2) is sufficiently large,the global bounded classical solution(u,v,w,z)of this system polynomially converges to(0,α_(1)/β_(1),1,0)as t→∞.

关键词： Chemotaxis predator-prey boundedness stabilization

Theil Utility Based multi-Device Cooperation Mechanism for Service Quality Equilibrium in Ubiquitous Stub Environments

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China Communications 2014年第6期11卷 140-150页

作者： RUI Lanlan mu Nan GUO Shaoyong qiu Xuesong ZHANG Jie State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications AsiaInfo-Linkage Inc.

An approach to make heterogeneous devices cooperate with each other to provide ubiquitous service remains a longstanding challenge in ubiquitous environments. In addition, when multi-user request ubiquitous services simultaneously, the arbitrariness in resource allocation process easily leads to non-equilibrium of qualities of multiuser's services. Thus, How to design an effective heterogeneous devices cooperation mechanism that meet the QoS requirements and also equilibrate QoS among multi-user's services becomes a very tough problem. In the paper, Equilibrium Index and Theil Utility function are imported to establish a multidevice equilibrium cooperation model, which is benefit for resource allocation in ubiquitous environments. Then a Theil-Equilibrium based Cooperation Mechanism for multi-service is proposed. Firstly, in order to simplify calculating, a dimensionless processing is introduced. After that, a cooperation approach with Theil-Utility Heuristic algorithm is designed to choose the best solution for the simplified model. At last, the mechanism is simulated in a smart home scenario. The simulation results show that this mechanism outperforms non-equilibrium method by improving almost 40% in internal equilibrium with just reducing 0-2% in the total utility ofall the requested ubiquitous services. These data show that the proposed mechanism performs well in equilibrating qualities of multi-user's ubiquitous services.

关键词： ubiquitousstub environments cooperation among multi-device QoS equilibrium equilibrium index theil utility

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选区激光熔化制备高熵合金的研究进展

金属加工(热加工) 2025年第1期 1-12+26页

作者：邱翔宇穆永坤贾延东上海大学材料研究所

高熵合金（HEAs）凭借其多主元特性，展现出远超传统合金的优异性能，然而传统制备方法在高熵合金的生产过程中存在诸多限制。随着先进制造技术的快速发展，选区激光熔化（Selective Laser Melting,SLM）技术在高熵合金的制备中展现出... 详细信息

高熵合金（HEAs）凭借其多主元特性，展现出远超传统合金的优异性能，然而传统制备方法在高熵合金的生产过程中存在诸多限制。随着先进制造技术的快速发展，选区激光熔化（Selective Laser Melting,SLM）技术在高熵合金的制备中展现出显著优势，例如，SLM能够高精度地成形复杂几何结构的高熵合金零件，其独特的高冷却速率特性可显著提升高熵合金的力学性能，因而受到研究者的广泛关注。通过系统介绍了SLM技术的基本原理以及高熵合金粉末的制备方法，总结了SLM制备高熵合金过程中的关键问题，包括缺陷形成、工艺参数优化、合金成分设计，以及后处理手段对材料微观组织和力学性能的影响，研究成果为高熵合金及SLM技术领域的进一步探索提供了理论参考与实践指导。

关键词：选区激光熔化高熵合金微观组织力学性能

Mechanism of vanadic titanomagnetite solid-state reduction

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Rare Metals 2020年第11期39卷 1348-1352页

作者： shui-Shi Liu Yu-Feng Guo Guan-Zhou qiu Tao Jiang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083China

The influence mechanism of vanadic titanomagnetite solid-state reduction was studied in this *** microscopy(OM),scanning electron microscope(SEM),and X-ray diffraction(XRD)were used to characterize the structure and phases of the *** results show that the dense structure is not the reason that limits the reducibility of Panxi vanadic *** rate of 93%was achieved when it was reduced at 1100℃for 100 *** pre-oxidation,Fe_(9)TiO_(15)and Fe_(2)O_(3)are the main phases of ***-oxidation could destroy the dense structure of vanadic titanomagnetite and increase the specific surface area of ***,reducibility of vanadic titanomagnetite is not improved obviously by pre-oxidation,with metallization rate increasing only 1%under the same reduction conditions,and the generated metallic iron grains are *** transformation of vanadic titanomagnetite at different reduction temperatures shows that the presence of FeTi_(2)O_(5)is the main reason that limits the reducibility of Panxi vanadic titanomagnetite.

关键词： Vanadic titanomagnetite Pre-oxidation Solid-state reduction Reduction process

Writing and erasing MYC ubiquitination and SUMOylation

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Genes & Diseases 2019年第4期6卷 359-371页

作者： Yingxiao Chen Xiao-Xin Sun Rosalie C.Sears mu-shui Dai Departments of Molecular&Medical Genetics School of MedicineOHSU Knight Cancer InstituteOregon Health&Science University3181 SW Sam Jackson Park RoadPortlandOR 97239USA

The transcription factor c-MYC(MYC thereafter)controls diverse transcription programs and plays a key role in the development of many human *** develop multiple mechanisms to ensure that MYC levels and activity are precisely controlled in normal physiological *** a short half-lived protein,MYC protein levels are tightly regulated by the ubiquitin proteasome *** a dozen of ubiquitin ligases have been found to ubiquitinate MYC whereas a number of deubiquitinating enzymes counteract this *** studies show that SUMOylation and deSUMOylation can also regulate MYC protein stability and ***,evidence suggests an intriguing crosstalk between MYC ubiquitination and *** of the MYC ubiquitination-SUMOylation regulatory network may contribute to *** review is intended to provide the current understanding of the complex regulation of the MYC biology by dynamic ubiquitination and SUMOylation and their crosstalk.

关键词： deSUMOylating enzymes Deubiquitinating enzymes MYC SUMO SUMOylation Ubiquitination

CONTINUOUS DEPENDENCE ON DATA UNDER THE LIPSCHITZ METRIC FOR THE ROTATION-CAMASSA-HOLM EQUATION

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Acta Mathematica Scientia 2021年第1期41卷 1-18页

作者： Xinyu TU Chunlai mu Shuyan qiu School of Mathematics and Statistics Southwest UniversityChongqing 400715China College of Mathematics and Statistics Chongqing UniversityChongqing 401331China

In this article,we consider the Lipschitz metric of conservative weak solutions for the rotation-Camassa-Holm *** on defining a Finsler-type norm on the tangent space for solutions,we first establish the Lipschitz metric for smooth solutions,then by proving the generic regularity result,we extend this metric to general weak solutions.

关键词： coriolis effect rotation-Camassa-Holm equation generic regularity Lipschitz metric

Bedside ultrasonic localization of the nasogastric tube in a patient with severe COVID-19:A case report

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World Journal of Clinical Cases 2022年第15期10卷 4911-4916页

作者： Xiao-Ju Zhu shui-Xia Liu qiu-Tang Li Yuan-Jing Jiang Cancer Center Daping HospitalArmy Medical UniversityChongqing 400042China Department of Neurology Daping HospitalArmy Medical UniversityChongqing 400042China

BACKGROUND The indwelling nasogastric tube is commonly used for supplying enteral nutrition to patients who are unable to feed themselves,and accurate positioning is essential in the indwelling nasogastric tube in the body of the aforementioned *** clinical practice,abdominal radiography,auscultation,and clinical determination of the pH of the gastric juice are routinely used by medical personnel to determine the position of the tube;however,those treatments have proved limitations in specific *** are few case reports on the precise positioning of the nasogastric tube in patients with coronavirus disease 2019(COVID-19),for whom a supply of necessary nutrition support is significant throughout the process of *** SUMMARY A 79-year-old patient,diagnosed with COVID-19 at the stage of combined syndromes with severe bacterial lung infection,respiratory failure,multiple comorbidities,and a poor nutritional status,was presented to us and required an indwelling nasogastric tube for enteral nutrition *** pre-treatment assessments including observation of the patient’s nasal feeding status and examination of the nasal septal deviation,inflammation,obstruction,nasal leakage of cerebrospinal fluid,and other disorders that might render intubation inappropriate,we measured and marked the length of the nasogastric tube to be placed and delivered the tube to the intended length in the standard *** further scrutiny was conducted to ensure that the tube was not coiled in the mouth,and gentle movements were made to avoid damage to the esophageal ***,back draw of the gastric juice using an empty needle failed,and the stethoscope could not be used for auscultation due to the specific condition presented by the internal organs of the patient,and the end of the tube was placed in saline with no bubbles spilling ***,it was not possible to determine whether the nasogastric tube was placed exactly in the stomach and no nutrient

关键词： Ultrasound Localization Nasogastric tube COVID-19 Nutrition supply Case report