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Morphological Assessment of the Small Intestine of Broilers Fed Dietary Natural Zeolite Including Plant Extract 被引量:2
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作者 T. Incharoen O. Khambualai K. Yamauchi 《Journal of Agricultural Science and Technology(A)》 2011年第8期1284-1287,共4页
Many kinds of feed additives (e.g., probiotics, prebiotics, antibiotics, etc.) can be used in chicken diets to stimulate intestinal morphological maturation and, consequently, intestinal function. The aim of this tr... Many kinds of feed additives (e.g., probiotics, prebiotics, antibiotics, etc.) can be used in chicken diets to stimulate intestinal morphological maturation and, consequently, intestinal function. The aim of this trial was to investigate the possibility that natural zeolite including plant extract (ZEM) could encourage the hypertrophy of intestinal villi and the absorptive function of epithelial cells in broiler chickens. At 7 days old, 64 male Marshall Chunky broilers were divided into four groups, each with four replicates of four chickens. The birds were fed a basal mash diet supplemented with ZEM at 0% (control), 0.05%, 0.1%, and 0.2% for 42 days. At 49 days old, four chickens from each treatment were killed to obtain intestinal samples. Morphological intestinal assessment was conducted using both a light and a scanning electron microscope. A tendency to increased villus height and cell area could be observed throughout the intestinal segments of the broilers fed ZEM. Particularly, the villus height in the duodenum was significantly increased (P 〈 0.05) in the 0.05% ZEM group when compared with the control group. The area of the villus cells tended to be higher in the ZEM groups in all intestinal regions and showed a significant increase (P 〈 0.05) in the ileal part of the 0.2% ZEM group. Also, the assessment of cells mitosis in the intestinal crypts showed significantly higher numbers (P 〈 0.05) in all levels of ZEM groups in the duodenum and a tendency to increase in value in the jejunum and ileum, as compared with the control group. More protuberated cells and multi-cell clusters were found in the ZEM groups than in the control group, resulting in a rough cellular surface. In conclusion, the present study might suggest that the intestinal villi and epithelial cells on the villus apical surface are hypertrophied in the ZEM groups, and that intestinal villi adapt to enhance their absorption capacity by increasing the absorptive surface area. These results are indicated that ZEM can provide effective nutritive value when used as a feed additive. 展开更多
关键词 Broiler chicken natural zeolite including plant extract intestinal morphology
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A Precise Description of the Electronic Structures and Spin-Allowed Transition Properties of PF and Its Cation:All-Electron Configuration-Interaction Investigations Including Relativistic Effect 被引量:1
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作者 李奇楠 赵书涛 +3 位作者 张晓美 罗旺 李瑞 闫冰 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期42-46,共5页
The electronic structures of PF and PF+ are calculated with the high-level configuration interaction method. To improve the precision of calculations, the spin-orbit coupling effect, the scalar relativistic effect, a... The electronic structures of PF and PF+ are calculated with the high-level configuration interaction method. To improve the precision of calculations, the spin-orbit coupling effect, the scalar relativistic effect, and the Davidson correction(q-Q) are also considered. The spectroscopic parameters of bound states are derived by the electronic structures of PF and PF+, which are in good accordance with the measurements. The transition dipole moments of spin-allowed transitions are evaluated, and the radiative lifetimes of several A S states of PF and PF+ are obtained. 展开更多
关键词 A Precise Description of the Electronic Structures and Spin-Allowed Transition Properties of PF and Its Cation:All-Electron Configuration-Interaction Investigations including Relativistic Effect PF TDM
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Anterior transhepatic approach for total caudate lobectomy including spigelian lobe,paracaval portion and caudate process:A Brazilian experience 被引量:1
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作者 Eduardo de Souza Martins Fernandes Carlo Alberto Pacilio +1 位作者 Felipe Pedreira Tavares de Mello Camila Liberato Girão 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第4期371-373,共3页
To the Editor:Nowadays,because of the infiltration of cholangiocarcinoma to the parenchyma and/or bile ducts of the caudate lobe,the inclusion of caudate lobe combined with a major hepatectomy remains the gold standar... To the Editor:Nowadays,because of the infiltration of cholangiocarcinoma to the parenchyma and/or bile ducts of the caudate lobe,the inclusion of caudate lobe combined with a major hepatectomy remains the gold standard approach for a resectable hilar cholangiocarcinoma.Since the last years of the 20th century,some authors have begun to report isolated caudate lobe resection for hepatocellular. 展开更多
关键词 HCC Anterior transhepatic approach for total caudate lobectomy including spigelian lobe paracaval portion and caudate process:A Brazilian experience
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Geometric Scaling Analysis of Deep Inelastic Scattering Data Including Heavy Quarks
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作者 吴庆东 曾吉 +3 位作者 胡元元 李权波 周代翠 向文昌 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期31-35,共5页
An analytic massive total cross section of photon proton scattering is derived, which has geometric scaling. A geometric scaling is used to perform a global analysis of the deep inelastic scattering data on inclusive ... An analytic massive total cross section of photon proton scattering is derived, which has geometric scaling. A geometric scaling is used to perform a global analysis of the deep inelastic scattering data on inclusive structure function F2 measured in lepton-hadron scattering experiments at small values of Bjorken x. It is shown that the descriptions of the inclusive structure function F2 and longitudinal structure function FL are improved with the massive analytic structure function, which may imply the gluon saturation effect dominating the parton evolution process at HERA. The inclusion of the heavy quarks prevent the divergence of the lepton-hadron cross section, which plays a significant role in the description of the photoproduction region. 展开更多
关键词 of on in Geometric Scaling Analysis of Deep Inelastic Scattering Data including Heavy Quarks that IS DATA been HAVE THAN from
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Specific Heat of a Unitary Fermi Gas Including Particle-Hole Fluctuation
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作者 阮小霞 宫昊 +1 位作者 石远美 宗红石 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第11期25-27,共3页
We investigate the particle-hole fluctuation correction to the specific heat of an ultracold Fermi gas at unitarity within the framework of the non-self-consistent T-matrix approximation in the normal phase. We find g... We investigate the particle-hole fluctuation correction to the specific heat of an ultracold Fermi gas at unitarity within the framework of the non-self-consistent T-matrix approximation in the normal phase. We find good agreement between our theoretical predictions and the experimental data measured by the MIT group, apart from discrepancies near the transition temperature. At high temperature, our calculated specific heat has the tendency to approach the specific heat of the Boltzmann gas. 展开更多
关键词 of in is Specific Heat of a Unitary Fermi Gas including Particle-Hole Fluctuation BEC BCS from heat
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Theoretical Study on the Spectroscopic Parameters and Transition Properties of MgH Radical Including Spin-orbit Coupling
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作者 伍冬兰 谭彬 +4 位作者 曾学锋 万慧军 谢安东 闫冰 丁大军 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期12-16,共5页
An accurate theoretical study on the MgH radical is reported by adopting the high-level relativistic MRCI+Q method with a quintuple-zeta quality basis set. The reliable potential energy curves of the five A-S states ... An accurate theoretical study on the MgH radical is reported by adopting the high-level relativistic MRCI+Q method with a quintuple-zeta quality basis set. The reliable potential energy curves of the five A-S states of MgH are derived. Then the associated spectroscopic parameters are determined and found to be in good accordance with the available experimental results. The permanent dipole moments (PDMs) and the spin-orbit (SO) matrix elements of A-S states are computed. The results show that the abrupt changes of PDMs and SO matrix elements are attributed to the variations of electronic configurations at the avoided crossing point. The SOC effect leads to the five A-S states split into ten Ω states and results in the double potential well of (2)1//2 state. Finally, the transition properties from the (2)1//2, (1)3//2 and (3)1//2 states to the ground state X2∑+1//2 transitions are obtained, including the transition dipole moments, Franck-Condon factors and radiative lifetimes. 展开更多
关键词 of on in Theoretical Study on the Spectroscopic Parameters and Transition Properties of MgH Radical including Spin-orbit Coupling SOC been that MRCI
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First Report of Late Miocene Mammals Including Chilotherium in the Xining Basin,NE Tibetan Plateau,China
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作者 HAN Jianen SHAO Zhaogang +6 位作者 XU Biao ZHANG Qianqian YU Jia MENG Qingwei MENG Xiangang ZHU Dagang WANG Jin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期1135-1136,共2页
Objective Xining basin is located in the northeastern Qinghai- Tibetan Plateau, which tectonic location belongs to a junction of the Kunlun and Qilian mountains. The southern, northern and western parts of the basin a... Objective Xining basin is located in the northeastern Qinghai- Tibetan Plateau, which tectonic location belongs to a junction of the Kunlun and Qilian mountains. The southern, northern and western parts of the basin are restricted by the Laji, Daban and Riyue mountains fault zones, and go eastward into the Longzhong basin in Gansu Province. A succession of Cenozoic lacustrine sedimentary strata has been well developed in the Xining basin, with sediments over 800 m thick. 展开更多
关键词 of as In on in First Report of Late Miocene Mammals including Chilotherium in the Xining Basin NE Tibetan Plateau China
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AROMATIC BOND INCLUDING METALLIC ATOM IN COORDINATE COMPOUNDS AND SOME OF ITS PROPERTIES
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作者 Jing Jiang LIU Yun Ti CHENDepartment of Chemistry,Nankai University,Tianjin,300071R.Kent MURMANNDepartment of Chemistry,University of Missouri Columbia MO 65211,U.S.A 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第5期363-366,共4页
Aromatic bond including metallic atom (Ni) is investigated by EHMO calculation.The NMR spectra and the mechanism for hydrolysis are discussed on the ground of results of computation.
关键词 Ni PN AROMATIC BOND including METALLIC ATOM IN COORDINATE COMPOUNDS AND SOME OF ITS PROPERTIES ITS
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Constraining Equation of State of Dark Matter:Including Weak Gravitational Lensing
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作者 杨磊 杨维强 徐立昕 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第5期183-187,共5页
Usually the equation of state (EoS) of dark matter is zero when it is cold, however there exists the possibility of a (effective) nonzero EoS of dark matter due to its decay and interaction with dark energy. In th... Usually the equation of state (EoS) of dark matter is zero when it is cold, however there exists the possibility of a (effective) nonzero EoS of dark matter due to its decay and interaction with dark energy. In this work, we try to constrain the EoS of dark matter/JAdm using the currently available cosmic observations which include the geometrical and dynamical measurements. For the geometrical measurements, the luminosity distance of type Ia supernovae, the angular diameter distance and comoving sound horizon from baryon acoustic oscillations and the cosmic microwave background radiation will be employed. The data points from the redshift-space distortion and weak gravitational lensing will be taken as dynamical measurements. Using the Markov chain Monte Carlomethod, we obtain a very tight constraint on the-EoS of dark matter:wdm=0.0000532 +0.000692+0.00136+0.00183 -0.000686-0.00136-0.00177. 展开更多
关键词 In Constraining Equation of State of Dark Matter:including Weak Gravitational Lensing PLANCK
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Polymorphic multiple hepatocellular adenoma including a non-steatotic HNF1α-inactivated variant
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作者 Kayvan Mohkam Benjamin Darnis +5 位作者 Jean-Baptiste Cazauran Agnès Rode Anne-Frédérique Manichon Christian Ducerf Brigitte Bancel Jean-Yves Mabrut 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2017年第5期552-555,共4页
To the Editor:Hepatocellular adenomas(HCAs)consist of benign liver tumors favored by the use of oral contraceptives,which preferentially occur in women.[1,2]They expose to the risk of hemorrhage(20%of cases)and more r... To the Editor:Hepatocellular adenomas(HCAs)consist of benign liver tumors favored by the use of oral contraceptives,which preferentially occur in women.[1,2]They expose to the risk of hemorrhage(20%of cases)and more rarely,to the risk of malignant transformation(4%-10%of cases).[3,4]Multiple HCAs,which are defined by the presence of 10 or more 展开更多
关键词 HNF Polymorphic multiple hepatocellular adenoma including a non-steatotic HNF1 HCA
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INTRALUMINAL ELASTIC CIRCULAR LIGATION FOR ESOPHAGOGASTRIC ANASTOMOSIS(INCLUDING THE CLINICAL ANALYSES OF 100 CASES)
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作者 张毓德 杜喜群 +1 位作者 王其彰 张增强 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第2期51-55,共5页
Between 1981 and 1988, 234 cases of cancerof the esophagus or gastric cardia were treatedby resection and intraluminal elastic circularligation for esophagogastric anastomosis. Thispresent study advances the results d... Between 1981 and 1988, 234 cases of cancerof the esophagus or gastric cardia were treatedby resection and intraluminal elastic circularligation for esophagogastric anastomosis. Thispresent study advances the results described inour earlier study. The details of technicalrefinements are here reported, based on the 展开更多
关键词 INTRALUMINAL ELASTIC CIRCULAR LIGATION FOR ESOPHAGOGASTRIC ANASTOMOSIS including THE CLINICAL ANALYSES OF 100 CASES
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From Neglecting to Including Cultivar-Specific Per Se Temperature Responses:Extending the Concept of Thermal Time in Field Crops
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作者 Lukas Roth Martina Binder +5 位作者 Norbert Kirchgessner Flavian Tschurr Steven Yates Andreas Hund Lukas Kronenberg Achim Walter 《Plant Phenomics》 SCIE EI CSCD 2024年第3期547-562,共16页
Predicting plant development,a longstanding goal in plant physiology,involves 2 interwoven components:continuous growth and the progression of growth stages(phenology).Current models for winter wheat and soybean assum... Predicting plant development,a longstanding goal in plant physiology,involves 2 interwoven components:continuous growth and the progression of growth stages(phenology).Current models for winter wheat and soybean assume species-level growth responses to temperature.We challenge this assumption,suggesting that cultivar-specific temperature responses substantially affect phenology.To investigate,we collected field-based growth and phenology data in winter wheat and soybean over multiple years.We used diverse models,from linear to neural networks,to assess growth responses to temperature at various trait and covariate levels.Cultivar-specific nonlinear models best explained phenology-related cultivar-environment interactions.With cultivar-specific models,additional relations to other stressors than temperature were found.The availability of the presented field phenotyping tools allows incorporating cultivar-specific temperature response functions in future plant physiology studies,which will deepen our understanding of key factors that influence plant development.Consequently,this work has implications for crop breeding and cultivation under adverse climatic conditions. 展开更多
关键词 temperature SPECIFIC CONCEPT CROPS field time from CULTIVAR EXTENDING including
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Period–luminosity and Period–luminosity–metallicity Relations forδScuti Stars
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作者 Yan-Qi Liu Xiao-Dian Chen +3 位作者 Shu Wang Kun Wang Qi Jia Li-Cai Deng 《Research in Astronomy and Astrophysics》 2025年第5期257-268,共12页
δScuti(δSct)stars are potential distance tracers for studying the Milky Way structure.We conduct a comprehensive analysis of the period-luminosity(PL)and period-luminosity-metallicity(PLZ)relations forδSct stars,in... δScuti(δSct)stars are potential distance tracers for studying the Milky Way structure.We conduct a comprehensive analysis of the period-luminosity(PL)and period-luminosity-metallicity(PLZ)relations forδSct stars,integrating data from the Zwicky Transient Facility,the Transiting Exoplanet Survey Satellite,Large Sky Area Multi-Object Fiber Spectroscopic Telescope,Apache Point Observatory Galactic Evolution Experiment,and Gaia.To mitigate the impact of the Gaia parallax zero point offset,we applied a correction method,determining the optimal zero point value to be zp(?)=35±2μas.Using the three best bands,by varying the parallax error threshold,we found that the total error of the PLR zero point was minimized to 0.9%at a parallax error threshold of 6%.With this threshold,we derived the PL and PLZ relations for nine bands(from optical to mid-infrared)and five Wesenheit bands.Through our analysis,we conclude that the influence of metallicity on the PLR ofδSct stars is not significant,and the differences across various bands are minimal. 展开更多
关键词 STARS distances-stars variables delta Scuti-stars oscillations(including pulsations)
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Peripheral nervous system and gut microbiota:Emerging evidence on increased mechanistic understanding to reveal innovative strategies for peripheral nerve regeneration
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作者 Giulia Ronchi Matilde Cescon +1 位作者 Giovanna Gambarotta Kirsten Haastert-Talini 《Neural Regeneration Research》 2026年第4期1560-1561,共2页
The gut microbiota:The human body is colonized by a diverse and complex microbial community–including bacteria,viruses,archaea,and unicellular eukaryotes–that plays a central role in human wellbeing.Indeed,microbiot... The gut microbiota:The human body is colonized by a diverse and complex microbial community–including bacteria,viruses,archaea,and unicellular eukaryotes–that plays a central role in human wellbeing.Indeed,microbiota is crucial for several functions,including host metabolism,physiology,maintenance of the intestinal epithelial integrity,nutrition,and immune function,earning it the designation of a“vital organ”(Guinane and Cotter,2013). 展开更多
关键词 unicellular eukaryotes human wellbeing gut microbiota peripheral nerve regeneration microbial community peripheral nervous system microbial community including host metabolism
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Four Total Eclipsing Contact Binary Systems:The First Photometric Light Curve Solutions Employing TESS and Gaia Surveys
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作者 Atila Poro Razieh Aliakbari +2 位作者 Hossein Azarara Asma Ababafi Sadegh Nasirian 《Research in Astronomy and Astrophysics》 2025年第3期131-140,共10页
We presented the first photometric light curve solutions of four W Ursae Majoris-type contact binary systems.This investigation utilized photometric data from the Transiting Exoplanet Survey Satellite and Gaia Data Re... We presented the first photometric light curve solutions of four W Ursae Majoris-type contact binary systems.This investigation utilized photometric data from the Transiting Exoplanet Survey Satellite and Gaia Data Release 3(DR3).We used the PHysics Of Eclipsing BinariEs Python code and the Markov Chain Monte Carlo method for these light curve solutions.Only TIC 249064185 among the target systems needed a cold starspot to be included in the analysis.Based on the estimated mass ratios for these total eclipse systems,three of them are categorized as low mass ratio contact binary stars.The absolute parameters of the systems were estimated using the Gaia DR3 parallax method and the orbital period and semimajor axis(P-a)empirical relationship.We ascertained that the TIC 318015356 and TIC 55522736 systems are A-subtypes,while TIC 249064185 and TIC 397984843 are W-subtypes,depending on each component’s effective temperature and mass.We estimated the initial masses of the stars,the mass lost by the binary system,and the systems’ages.We displayed star positions in the mass-radius,mass-luminosity,and total mass-orbital angular momentum diagrams.In addition,our findings indicate a good agreement with the mass-temperature empirical parameter relationship for the primary stars. 展开更多
关键词 (stars )binaries(including multiple) close-stars fundamental parameters-methods data analysis
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Reactive oxygen species generation by organic materials for efficient photocatalysis
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作者 Qing Liu Tangxin Xiao +1 位作者 Zhouyu Wang Leyong Wang 《Chinese Chemical Letters》 2025年第10期1-3,共3页
Reactive oxygen species(ROS),including singlet oxygen(^(1)O_(2)),hydroxyl radicals(·OH),and superoxide anions(O_(2)^(·-)),are highly reactive molecules that play central roles in many chemical,biological,and... Reactive oxygen species(ROS),including singlet oxygen(^(1)O_(2)),hydroxyl radicals(·OH),and superoxide anions(O_(2)^(·-)),are highly reactive molecules that play central roles in many chemical,biological,and environmental processes due to their strong oxidative power[1].Generating ROS in a controlled manner under mild conditions is essential for achieving selective oxidation reactions.Light-driven methods are especially appealing for this purpose,as they offer precise control over where and when ROS are produced. 展开更多
关键词 superoxide anions o hydroxyl radicals superoxide anions reactive oxygen species singlet oxygen reactive oxygen species ros including selective oxidation reactionslight driven PHOTOCATALYSIS
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The FAST Galactic Plane Pulsar Snapshot Survey. Ⅶ. Six Millisecond Pulsars in Compact Orbits with Massive White Dwarf Companions
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作者 Z.L.Yang J.L.Han +12 位作者 T.Wang P.F.Wang W.Q.Su W.C.Chen C.Wang D.J.Zhou Y.Yan W.C.Jing N.N.Cai L.Xie J.Xu H.G.Wang R.X.Xu 《Research in Astronomy and Astrophysics》 2025年第1期64-74,共11页
Binary millisecond pulsars with a massive white dwarf(WD)companion are intermediate-mass binary pulsars(IMBPs).They are formed via the Case BB Roche-lobe overflow evolution channel if they are in compact orbits with a... Binary millisecond pulsars with a massive white dwarf(WD)companion are intermediate-mass binary pulsars(IMBPs).They are formed via the Case BB Roche-lobe overflow evolution channel if they are in compact orbits with an orbital period of less than 1 day.They are fairly rare in the known pulsar population;only five such IMBPs have been discovered before,and one of them is in a globular cluster.Here we report six IMBPs in compact orbits:PSRs J0416+5201,J0520+3722,J1919+1341,J1943+2210,J1947+2304 and J2023+2853,discovered during the Galactic Plane Pulsar Snapshot survey by using the Five-hundred-meter Aperture Spherical radio Telescope,doubling the number of such IMBPs due to the high survey sensitivity in the short survey time of 5 minutes.Follow-up timing observations show that they all have either a CO WD or an ONeMg WD companion with a mass greater than about 0.8M_(⊙)in a very circular orbit with an eccentricity in the order of10^(−5).PSR J0416+5201 should be an ONeMg WD companion with a remarkable minimum mass of 1.28M_(⊙).These massive WD companions lead to a detectable Shapiro delay for PSRs J0416+5201,J0520+3722,J1943+2210,and J2023+2853,indicating that their orbits are highly inclined.From the measurement of the Shapiro delay,the pulsar mass of J1943+2210 was constrained to be 1.84^(+0.11)_(-0.09)M_(⊙),and that of PSR J2023+2853 to be 1.28^(+0.06)_(-0.05)M_(⊙). 展开更多
关键词 (stars:)binaries(including multiple) close-stars evolution-(stars:)pulsars general
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Producing Type Ia Supernovae from Hybrid CONe White Dwarfs with Mainsequence Binary Companions at Low Metallicity of Z=0.0001
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作者 Boyang Guo Xiangcun Meng +2 位作者 Zhijia Tian Jingxiao Luo Zhengwei Liu 《Research in Astronomy and Astrophysics》 2025年第1期344-356,共13页
The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white... The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white dwarfs(CONe WDs)when they grow in mass to approach the Chandrasekhar mass limit by accreting matter from a binary main-sequence(MS)companion.In this work,we combine the results of detailed binary evolution calculations with population synthesis models to investigate the rates and delay times of SNe Ia in the CONe WD+MS channel at a low metallicity environment of Z=0.0001.For a constant star formation rate of 5M_(⊙)yr^(−1),our calculations predict that the SN Ia rates in the CONe WD+MS channel at low metallicity of Z=0.0001 is about 0.11−3.89×10^(−4) yr^(−1).In addition,delay times in this channel cover a wide range of 0.05−2.5 Gyr.We further compare our results to those given by a previous study for the CONe WD+MS channel with a higher metallicity of Z=0.02 to explore the influence of metallicity on the results.We find that these two metallicity environments give a slight difference in rates and delay times of SNe Ia from the CONe WD+MS channel,although SNe Ia produced at a low metallicity environment of Z=0.0001 have relatively longer delay times. 展开更多
关键词 methods numerical-(stars:)binaries(including multiple) close-stars evolution-(stars:)supernovae general-(stars:)white dwarfs
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Jets are the Most Robust Observable Ingredient of Common Envelope Evolution
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作者 Noam Soker 《Research in Astronomy and Astrophysics》 2025年第2期232-238,共7页
I examine images of 50 planetary nebulae(PNe)with observable post-common envelope evolution(CEE)binary central stars and find that jets are about 40%more common than dense equatorial outflows.Because,in some cases,ene... I examine images of 50 planetary nebulae(PNe)with observable post-common envelope evolution(CEE)binary central stars and find that jets are about 40%more common than dense equatorial outflows.Because,in some cases,energetic jets can compress an equatorial outflow and because fast jets might disperse early in the PN evolution and avoid detection,the CEE process is likelier to launch jets than to eject a dense equatorial outflow by a larger factor than 1.4.In most cases,the companion,mainly a main sequence star,launches the jets as it accretes mass from the envelope of the giant star.By CEE jets,I also refer to jets launched shortly before the onset of the CEE,likely a grazing envelope evolution phase,and shortly after the CEE.The jets and the accretion of mass by the companion before,during,and after the CEE affect envelope mass removal and the final orbital separation.Most numerical simulations of the CEE ignore jets,and those that include jets omit other processes.Despite the considerable progress in the last decade with tens of hydrodynamical simulations of the CEE,we are still far from correctly simulating the CEE.Including jets in simulations of the CEE requires heavy computer resources,but it must be the next step. 展开更多
关键词 stars:jets stars:AGB and post-AGB (stars:)binaries(including multiple):close stars:winds outflows (ISM:)planetary nebulae:general
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O'Connell Effect and Period Variations on Solar-like Contact Binary EF Boo
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作者 Jing-Jing Wang Meng Guo +1 位作者 Xiao-Man Tian Bin Zhang 《Research in Astronomy and Astrophysics》 2025年第2期46-59,共14页
Using ground-based telescopes,the multi-color photometric observations of the contact binary EF Boo were obtained in 2020,2023,and 2024.Combining these with 7-sectors of light curves from TESS data,the variations of t... Using ground-based telescopes,the multi-color photometric observations of the contact binary EF Boo were obtained in 2020,2023,and 2024.Combining these with 7-sectors of light curves from TESS data,the variations of the O'Connell effect in continuous time and shapes of light curves over several years were identified.Three sets of typical light curves were analyzed to determine the photometric solutions via the Wilson-Devinney program.Considering the spectroscopic mass ratio of q=0.53,these photometric solutions suggest that EF Boo is a W-type W UMa contact binary with the averaged filling factor of f=22.26%,a small temperature difference,and a cool spot on the primary component.If the variations of the O'Connell effect are due to the magnetic activity of this cool spot,the longitudinal location varied from 50.4 to 302.7 over the time interval of 1434 days.Based on all CCD minimum times from ground-based telescope and TESS data,the O-C curve was also analyzed.A cyclic oscillation(A3=0.00575 days,T3=27.8 yr)superimposed on a secular increase(dP/dt=6.74×10^(-8)day yr^(-1))was discovered for the first time.The successive increase is possibly a result of mass transfer from the less massive star to the more massive one.The cyclic oscillations were possibly explained by the light-travel time effect via a third body or the magnetic activities.From the short cadence observations from TESS,we also calculated the value of the O'Connell effect and O-C value for each cycle and found no correlation between the O'Connell effect and O-C over nearly 30 days across different sectors. 展开更多
关键词 (stars:)binaries(including multiple):close (stars:)binaries:eclipsing stars:solar-type stars:individual(EF Boo)
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