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The mid-infrared variability of the SDSS optical quasars

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Research in Astronomy and Astrophysics 2020年第2期20卷 67-74页

作者： Hong-Tao Wang yong shi School of Astronomy and Space Science Nanjing UniversityNanjing 210093China The School of Science Langfang Normal UniversityLangfang 065000China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityNanjing 210023China

Based on the Seventh Data Release(DR7) quasar catalog from the Sloan Digital Sky Survey,we investigate the variability of optical quasars in W1,W2,W3 and W4 bands of the Wide-field Infrared Survey Explorer(WISE) and the Near-Earth Object Wide-field Infrared Survey Explorer(NEOWISE).Adopting the structure function(SF) method,we calculate the SF(δt = 1 yr) which shows no obvious correlations with the bolometric luminosity,the black hole mass and the Eddington *** ensemble SFs in W1 and W2 bands show that the SF slopes are steeper than those in previous studies which may be caused by different cadence and observational epoch *** further investigate the relation of variability amplitude σmbetween mid-infrared band and optical band,but no obvious correlation is *** correlation is found between W1–W2 and g-r *** think that the mid-infrared emission of quasars may be smoothed out by the extended dust distribution,thus leading to no obvious *** the radio-loud quasar sub-sample,we further analyze the relation between the variability amplitude in the mid-infrared band and the radio luminosity at 6 cm,but no obvious correlations are found,which indicate the mid-infrared emission contributed from the synchrotron radiation of the relativistic jet is very weak.

关键词： quasar:variability quasar:mid-IR quasar:characteristics

Nonconforming Finite Element Methods for the Constrained Optimal Control Problems Governed by Nonsmooth Elliptic Equations

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Acta Mathematicae Applicatae Sinica 2020年第2期36卷 471-481页

作者： Hong-bo GUAN Dong-yang shi College of Mathematics and Information Sciences Zhengzhou University of Light IndustryZhengzhou 450002China School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

In this paper,nonconforming finite element methods(FEMs)are proposed for the constrained optimal control problems(OCPs)governed by the nonsmooth elliptic equations,in which the popular EQr1 ot element is employed to approximate the state and adjoint state,and the piecewise constant element is used to approximate the ***,the convergence and superconvergence properties for the nonsmooth elliptic equation are obtained by introducing an auxiliary ***,the goal-oriented error estimates are obtained for the objective function through establishing the negative norm error ***,the methods are extended to some other well-known nonconforming elements.

关键词： nonconforming finite element supercloseness and superconvergence optimal control problems nonsmooth elliptic equations goal-oriented error estimate

Dielectronic Recombination for the Self-Consistent-Field Average Ions

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Chinese Physics Letters 1996年第9期13卷 664-667页

作者： ZHAO Li-bo LI shi-chang Institute of Applied Physics and Computational Mathematics Beijing 100088

A self-consistent-field theoretical method has been developed to treat the dielectronic recombination(DR)of average ions with *** on the method,the rate coefficients for DR into a special state can be *** an example,t... 详细信息

关键词： population method presented

Nitrogen application levels based on critical nitrogen absorption regulate processing tomatoes productivity, nitrogen uptake, nitrate distributions, and root growth in Xinjiang, China

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Journal of Arid Land 2023年第10期15卷 1231-1244页

作者： JING bo shi Wenjuan DIAO Ming Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization of Xinjiang Production and Construction Corps Department of HorticultureAgricultural CollegeShihezi UniversityShihezi 832003China State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi'an University of TechnologyXi'an 710048China

The unreasonable nitrogen(N)supply and low productivity are the main factors restricting the sustainable development of processing *** addition,the mechanism by which the N application strategy affects root growth and nitrate distributions in processing tomatoes remains *** this study,we applied four N application levels to a field(including 0(N0),200(N200),300(N300),and 400(N400)kg/hm^(2))based on the critical N absorption ratio at each growth stage(planting stage to flowering stage:22%;fruit setting stage:24%;red ripening stage:45%;and maturity stage:9%).The results indicated that N300 treatment significantly improved the aboveground dry matter(DM),yield,N uptake,and nitrogen use efficiency(NUE),while N400 treatment increased nitrate nitrogen(NO_(3)^(-)-N)residue in the 20–60 cm soil *** variations of total root dry weight(TRDW)and total root length(TRL)showed a single-peak ***,N300 treatment improved the secondary root parameter of TRDW,while N400 treatment improved the secondary root parameter of *** grey correlation coefficients indicated that root dry weight density(RDWD)in the surface soil(0–20 cm)had the strongest relationship with yield,whereas root length density(RLD)in the middle soil(20–40 cm)had a strong relationship with *** path model indicated that N uptake is a crucial factor affecting aboveground DM,TRDW,and *** above results indicate that N application levels based on critical N absorption improve the production of processing tomatoes by regulating N uptake and root ***,the results of this study provide a theoretical basis for precise N management.

关键词： critical N absorption nitrogen use efficiency(NUE) beta model total root dry weight(TRDW) root growth processing tomato

Connectivity differences between adult male and female patients with attention deficit hyperactivity disorder according to resting-state functional MRI

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Neural Regeneration Research 2016年第1期11卷 119-125页

作者： bo-yong Park Hyunjin Park Department of Electronic Electrical and Computer Engineering Sungkyunkwan University School of Electronic Electrical Engineering Sungkyunkwan University Center for Neuroscience Imaging Research (CNIR) Institute for Basic Science

Attention deficit hyperactivity disorder（ADHD） is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have explored the differences. The purpose of this study was to quantify differences between adult male and female patients with ADHD based on neuroimaging and connectivity analysis. Resting-state functional magnetic resonance imaging scans were obtained and preprocessed in 82 patients. Group-wise differences between male and female patients were quantified using degree centrality for different brain regions. The medial-, middle-, and inferior-frontal gyrus, superior parietal lobule, precuneus, supramarginal gyrus, superior- and middle-temporal gyrus, middle occipital gyrus, and cuneus were identified as regions with significant group-wise differences. The identified regions were correlated with clinical scores reflecting depression and anxiety and significant correlations were found. Adult ADHD patients exhibit different levels of depression and anxiety depending on sex, and our study provides insight into how changes in brain circuitry might differentially impact male and female ADHD patients.

关键词： neural regeneration connectivity attention deficit hyperactivity disorder sex difference functional magnetic resonance imaging depression anxiety network analysis degree centrality diagnostic and statistical manual score

Crystallization of a Ti-based Bulk Metallic Glass Induced by Electropulsing Treatment

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Journal of Iron and Steel Research International 2016年第1期23卷 69-73页

作者： yong-jiang HUANG Xiang CHENG Hong-bo FAN shi-song GUAN Zhi-liang NING Jian-fei SUN National Key Laboratory of Precision Hot Processing of Metals Harbin Institute of Technology School of Materials Science and Engineering Harbin Institute of Technology

The effect of electropulsing treatment（EPT）on the microstructure of a Ti-based bulk metallic glass（BMG）has been *** maximum current density applied during EPT can exert a crucial role on tuning the microstructure of the *** the maximum current density is no more than 2 720A/mm^2,the samples retains amorphous nature,whereas,beyond that,crystalline phases precipitate from the glassy *** EPT,the maximum temperature within the samples EPTed at the maximum current densities larger than 2 720A/mm^2 is higher than the crystallization temperature of the BMG,leading to the crystallization event.

关键词： bulk metallic glass electropulsing transmission electron microscopy crystallization microstructure

On Proof of the C^1 Stability Conjecture

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Acta Mathematica Sinica,English Series 2005年第3期21卷 533-540页

作者： yong ZHANG Shao bo GAN School of Mathematical Sciences Soochow University Suzhou 215006 P. R. China School of Mathematical Sciences Peking University Beijing 100084 P. R. China

It seems that in Mane＇s proof of the C^1 Ω-stability conjecture containing in the famous paper which published in I. H. E. S. （1988）, there exists a deficiency in the main lemma which says that for f ∈F^1 （M） there exists a dominated splitting TMPi（f） =Ei^s the direlf sum of E and F Fi^u（O 〈 i 〈 dim M） such that if Ei^s is contracting, then Fi^u is expanding. In the first part of the paper, we give a proof to fill up this deficiency. In the last part of the paper, we, under a weak assumption, prove a result that seems to be useful in the study of dynamics in some other stability context.

关键词： The C^1 stability conjecture Dominated splitting Shadowing property Axiom A No-cycle condition

Response of porcine hepatocytes in primary culture to plasma from severe viral hepatitis patients

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World Journal of Gastroenterology 2005年第48期11卷 7585-7590页

作者： yong-bo Cheng Ying-Jie Wang shi-Chang Zhang Jun Liu Zhi Chen Jia-Jia Li Institute of Infectious Diseases Southwest Hospital Third Military Medical University Chongqing 400038 China

AIM： To observe the effects of plasma from patients with severe viral hepatitis （SVHP） on the growth and metabolism of porcine hepatocytes and the clinical efficiency of bioartificial liver device.METHODS： Hepatocytes were isolated from male porcines by collagenase perfusion. The synthesis of DNA and total protein, leakages of AST and LDH, changes in glutathione （GSH）, catalase and morphology of porcine hepatocytes exposed to SVHP were investigated to indicate the effect of plasma from patients with severe hepatitis on the growth, injury, detoxification, and morphology of porcine hepatocytes.RESULTS： The synthesis of DNA and protein was inhibited in the medium containing 100% SVHP compared to the controls. The leakages of LDH and AST increased in porcine hepatocytes following exposure to 100% SVHP for 5 h. The difference between 100% SVHP and 10% newborn calf serum （NCS） was significant in t-test （LDH： t = 24.552, P = 0.001; AST： t = 4.169, P = 0.014）. After exposure to SVHP for 24 h, alterations in GSH status were significant （F = 2.746, P〈0.05） between porcine hepatocytes in 100% SVHP and 10% NCS, but no alteration occurred in the culture medium after 48 h （F = 4.378, ,P〈0.05）. A similar profile was observed in catalase activity. Many round vacuoles were observed in porcine hepatocytes cultured in SVHR The membranes of these cells became indistinct and almost all the cells died on d 5.CONCLUSION： Plasma from patients with severe hepatitis inhibits the growth, injures membrane, disturbs GSH homeostasis and induces morphological changes of porcine hepatocytes, It is suggested that SVHP should be pretreated to reduce the toxin load and improve the performance of porcine hepatocytes in extracorporeal liver-support devices.

关键词： Bioartificial liver Porcine hepatocytes Cellculture Plasma toxicity

Formation Mechanism of Biomass Aromatic Hydrocarbon Tar on Quantum Chemistry

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Journal of Renewable Materials 2022年第12期10卷 3491-3504页

作者： bo Chen bo Liu yong Chao Chao Zhong School of Mechanical Engineering Hunan Institute of EngineeringXiangtan411104China School of Electrical and Information Engineering Hunan Institute of EngineeingXiangtan411104China Hunan Shuanghuan Fiber Forming Equipment Co ItdXiangtan411100China

The formation process of aromatic hydrocarbon tar during the pyrolysis process of biomass components of cel-lulose and lignin was carried out by quantum chemical calculation based on density functional theory method B3LYP/6-31G++(d,p).5 Hydroxymethylfurfural was chosen as the model compound of cellulose and hemicel-lulose,and syringa ldehyde was chosen as the model compound of *** calculation results show that the formation process of cellulose monocyclic aromatic hydrocarbon tar is the conversion process of benzene ring from furan ring,and the highest reaction energy barrier appears in the process of decarbonylation,which is 370.8 kJ/*** formation of lignin monocyclic aromatic hydrocarbon tar is mainly the process of side chains removal and the formation of phenol,The highest reaction energy barrier appears in the process of decarbonyla-tion,which is 374.9 kJ/*** reaction mechanism of phenanthrene formation from naphthalene was selected as the formation of cellulose and lignin polycydic aromatic hydrocarbon *** calculation results show that he total barrier of the pathway that naphthalene dehydrogenates to form naphthalene free radicals and then reacts with ethylene twice by addition action,finally occurs cydization reactions and isomerizes to produce phenan-threne is lowest,that is 38.6 kJ/*** it is proved that the evolution of tar is the process of deoxygenation and cyclization with the increase of the temperature from a theoretical point of view.

关键词： Cellulose lignin tar aromatic hydrocarbon quantum chemistry