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The gamma-ray spectral index changes for blazars

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Science China(Physics,Mechanics & Astronomy) 2012年第11期55卷 2179-2185页

作者： YANG JiangHe FAN JunHui nie jianjun YANG RuShu Department of Physics and Electronics Science Hunan University of Arts and ScienceChangde 415000China Center for Astrophysics Guangzhou UniversityGuangzhou 510405China

Based upon Fermi 1FGL and EGRET 3EG samples, a sample including 79 blazars （53 FSRQs, 26 BL Lacs） is presented. It is investigated that the correlations between the ratio of EGRET to Fermi blazars g-ray flux densities and the spectral index differ for EGRET to Fermi blazars for three subclasses of high-frequency peaked BL Lacertae objects-HBL, low-frequency peaked BL Lacertae objects-LBL, and flat spectrum radio quasars-FSRQs. There is a consistent relationship between the ratio of the two γ-ray flux densities and the spectral index difference for the three subclasses. It suggests that the spectrum changed with the source brightness in the gamma-ray band. Both the spectral index difference and the correlation slopes follow a continuous sequence from FSRQs to LBLs to HBLs, which is consistent with the noted blazar sequence.

关键词： active galactic nuclei (AGN) blazars gamma-ray emission spectral index

Some statistical correlation analyses for Fermi/LAT Blazars

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Science China(Physics,Mechanics & Astronomy) 2014年第10期57卷 2007-2014页

作者： nie jianjun FAN JunHui YANG RuShu YANG JiangHe Department of Physics and Electronics Science Hunan University of Arts and Science Center for Astrophysics Guangzhou University

A sample including 664 blazars （301 Flat Spectrum Radio Quasars and 363 BL Lacs） with ）γ-ray data in both 1FGL and 2FGL catalogues were selected. The average values of both y-photon average energy and the photon spectral index for FSRQs, LBLs, IBLs and HBLs, follow the blazars sequence, FSRQs → LBLs →IBLs → HBLs. The slopes of correlation between photon spectral index and ）,-ray luminosity for 4 the sub-classes of blazars also follow the blazars sequence. Also, there was close an- ti-correlations between the difference of two ）,-ray photon spectral indices and the logarithm of the ratio of two y-ray luminosities from 2FGL and 1FGL catalogs. It implies that the spectrum becomes flat when the source becomes brighter in high energetic γ-ray band. Lastly, the Kolmogolov-Smirnov test （KS test） of the average γ-photon energy showed that HBLs differs from LBLs and FSRQs, while there was no clear difference between LBLs and FSRQs, which implied that the γ-ray emissions in LBLs and FSRQs may be a result of the same emission mechanism.

关键词： Fermi blazars gamma-ray emission spectral index

Effective spectral index properties for Fermi blazars

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Science China(Physics,Mechanics & Astronomy) 2018年第5期61卷 46-52页

作者： JiangHe Yang JunHui Fan Yi Liu YueLian Zhang ManXian Tuo jianjun nie YuHai Yuan Department of Physics and Electronics Science Hunan University of Arts and Science Changde 415000 China Center for Astrophysics Guangzhou University Guangzhou 510006 China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006 China Mathematics and Computational Science Hunan University of Arts and Science Changde 415000 China

Blazars are a special subclass of active galactic nuclei with extreme observation properties. This subclass can be divided into two further subclasses of flat spectrum radio quasars(FSRQs) and BL Lacertae objects(BL Lacs) according to their emission line features. To compare the spectral properties of FSRQs and BL Lacs, the 1.4 GHz radio, optical R-band, 1 keV X-ray, and 1 GeVy-ray flux densities for 1108 Fermi blazars are calculated to discuss the properties of the six effective spectral indices of radio to optical(α_(RO)), radio to X-ray(α_(RX)), radio to y ray(α_(Ry)), optical to X-ray(α_(OX)), optical to y ray(α_(Oy)), and X-ray to y ray(α_(Xy)).The main results are as follows: For the averaged effective spectral indices, α_(OX_> α_(Oy)> α_(Xy)> α_(Ry)> α_(RX)> α_(RO) for samples of whole blazars and BL Lacs; α_(Xy)≈α_(Ry)≈α_(RX) for FSRQs and low-frequency-peaked BL Lacs(LBLs); and α_(OX)≈α_(Oy)≈α_(Xy) for high-synchrotron-frequency-peaked BL Lacs(HBLs). The distributions of the effective spectral indices involving optical emission(α_(RO), α_(OX), and α_(Oy)) for LBLs are different from those for FSRQs, but if the effective spectral index does not involve optical emission(α_(RX), α_(Ry), and α_(Xy)), the distributions for LBLs and FSRQs almost come from the same parent population. X-ray emissions from blazars include both synchrotron and inverse Compton (IC) components; the IC component for FSRQs and LBLs accounts for a larger proportion than that for HBLs; and the radiation mechanism for LBLs is similar to that for FSRQs, but the radiation mechanism for HBLs is different from that for both FSRQs and LBLs in X-ray bands. The tendency of α_(Ry) decreasing from LBLs to HBLs suggests that the synchrotron self-Compton model explains the main process for highly energetic y rays in BL Lacs.

关键词： active galactic nuclei (AGNs) blazars effective spectral index

Estimation of inverse Compton peak frequency for 4FGL Blazars

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Science China(Physics,Mechanics & Astronomy) 2023年第4期66卷 142-157页

作者： JiangHe Yang JunHui Fan Yi Liu ManXian Tuo ZhiYuan Pei WenXin Yang YuHai Yuan SiLe He ShengHui Wang XiaoHai Qu YueLian Zhang jianjun nie XiuHui Chen College of Mathematics and Physics Science Hunan University of Arts and ScienceChangde 415000China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China

This study uses a parabolic equation to fit the Inverse Compton (IC) spectral component of 3743 blazars (794 FSRQs,1432 BLLacs,and 1517 BCUs) from the 4FGL-DR3 *** mutual correlations are investigated,and a Bayesian classification is performed to the IC peak *** analyses draw the following conclusions:(1) The Bayesian classification shows two components with a dividing boundary of log(v_(p)^(IC)/Hz)pIC=***,the 3743 blazars are divided into low IC peak frequency(LCP) blazars and high IC peak frequency (HCP) blazars.(2) A strong linear correlation exists between IC peak frequency(logv_(p)^(IC)) and γ-ray photon spectral index (Γ).The IC peak frequency can be estimated by an empirical relation logv_(p)^(IC)=–4.5·Γ+32.8 for BL Lacs and logv_(p)^(IC)=4.0+31.4pICfor FSRQs,which is consistent with the result by Abdo et al.(3) The ICspectral curvature and IC peak frequency are not as closely related as the synchrotron curvature and the synchrotron peak frequency.(4) An anti-correlation exists between IC peak frequency and IC peak luminosity,implying that as the IC peak frequency in the γ-ray band decreases,the source becomes more *** beaming effect is stronger for the source with a lower IC peak frequency.(5) Positive correlations exist between IC and synchrotron components for both peak frequencies and peak fluxes,but no clear correlation exists between IC curvature and synchrotron curvature.

关键词： active galactic nuclei Fermi blazars spectral energy distribution inverse Compton emission

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实际联合动力循环有限时间热力学研究

中国机械工程 2007年第11期18卷 1273-1277页

作者：聂建军杜发荣高峰北京航空航天大学北京100083

基于有限时间内传热不可逆情况,用有限时间热力学方法建立了内可逆内燃机循环与斯特林循环相结合的联合动力装置的热力学模型,导出了以压缩比、温度比等循环参数表示的联合循环功率和效率表达式,通过对温度比(斯特林循环吸热温度与内燃... 详细信息

基于有限时间内传热不可逆情况,用有限时间热力学方法建立了内可逆内燃机循环与斯特林循环相结合的联合动力装置的热力学模型,导出了以压缩比、温度比等循环参数表示的联合循环功率和效率表达式,通过对温度比(斯特林循环吸热温度与内燃机循环初始放热温度的比值)的数值计算分析,验证了温度比对联合循环功率和效率的影响,以及联合循环功率与效率之间的关系。该分析结果对联合循环动力装置的性能研究具有实际指导意义。

关键词：有限时间热力学联合循环内燃机斯特林

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柴油机气道改进设计的现代设计流程及应用

农业机械学报 2006年第10期37卷 15-18页

作者：聂建军杜发荣高峰北京航空航天大学汽车工程系

分析了柴油机气道传统设计流程和现代设计方法的差异,并介绍了气道现代设计的关键技术。按照现代设计流程,改进设计了385型直喷式柴油机的气道,并对改进前后的气道进行了对比试验,取得了良好的效果。由此可知,现代设计方法是降低发动机... 详细信息

分析了柴油机气道传统设计流程和现代设计方法的差异,并介绍了气道现代设计的关键技术。按照现代设计流程,改进设计了385型直喷式柴油机的气道,并对改进前后的气道进行了对比试验,取得了良好的效果。由此可知,现代设计方法是降低发动机设计成本、缩短产品开发周期的有效手段。

关键词：柴油机气道现代设计方法

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铸铁类零件精加工用PCBN刀具材料的制备

工具技术 2017年第10期51卷 88-91页

作者：聂建军李辉中原工学院河南金六方超硬材料有限公司

介绍了铸铁类零件精加工用细颗粒整体聚晶立方氮化硼刀具材料的组分配比和制备方法,并对制备过程中的关键技术进行了研究。为了解决细颗粒原料粉体的团聚问题,通过试验研究确定了湿式球磨工艺参数以及所用的分散介质和分散剂;采用XRD分... 详细信息

介绍了铸铁类零件精加工用细颗粒整体聚晶立方氮化硼刀具材料的组分配比和制备方法,并对制备过程中的关键技术进行了研究。为了解决细颗粒原料粉体的团聚问题,通过试验研究确定了湿式球磨工艺参数以及所用的分散介质和分散剂;采用XRD分析和显微硬度等先进检测手段确定了制备聚晶立方氮化硼刀具材料的最佳工艺参数;针对重度断续切削要求高冲击韧性的刀具材料的应用场合,试验研究了纳米晶须对刀具材料性能的影响情况。结果表明,纳米晶须能够提高刀具材料的抗冲击韧性,但其添加量具有最佳范围。对PCBN刀具材料的微观组织结构和性能进行的分析结果表明,制备的PCBN刀具材料微观组织结构均匀、致密,性能稳定,能够满足精加工铸铁类零件的表面粗糙度要求。

关键词：铸铁立方氮化硼高速精加工

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淬火钢高速精加工用PCBN刀具材料的研究

工具技术 2016年第6期50卷 60-63页

作者：聂建军李辉中原工学院河南金六方超硬材料有限公司

介绍了一种低CBN含量的淬火钢精加工用PCBN刀具新材料的制备方法,确定了由细粒度CBN微粉和陶瓷成分为主要结合剂的材料的组分配比、组装结构和合成工艺参数。通过SEM电镜扫描、硬度和致密度检测手段对PCBN刀具材料的微观组织结构和性能... 详细信息

介绍了一种低CBN含量的淬火钢精加工用PCBN刀具新材料的制备方法,确定了由细粒度CBN微粉和陶瓷成分为主要结合剂的材料的组分配比、组装结构和合成工艺参数。通过SEM电镜扫描、硬度和致密度检测手段对PCBN刀具材料的微观组织结构和性能进行了分析研究,分析结果表明制备的PCBN刀具材料具有很高的硬度和致密度,微观组织结构均匀、致密。最后通过切削加工试验验证了制备的PCBN刀具材料具备良好的耐磨性,工件表面加工质量说明本文制备的PCBN刀具材料适合淬火钢的精加工。

关键词：淬火钢立方氮化硼高速精加工

单光子纠缠态的纠缠转移和量子隐形传态(英文)

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光子学报 2006年第5期35卷 776-779页

作者：蔡新华聂建军郭杰荣湖南文理学院物理与电子科学系湖南415000

使用光学分束器和单光子源,利用单光子态和真空态制备出了纠缠单光子态.利用光学分束器作用和单光子探测,实现了三个通讯伙伴之间的纠缠转移.提出了一个关于纠缠单光子态的量子隐形传态方案.在这个方案中,被传送的是一个未知的单光子纠... 详细信息

使用光学分束器和单光子源,利用单光子态和真空态制备出了纠缠单光子态.利用光学分束器作用和单光子探测,实现了三个通讯伙伴之间的纠缠转移.提出了一个关于纠缠单光子态的量子隐形传态方案.在这个方案中,被传送的是一个未知的单光子纠缠态.通讯双方使用的量子信道是两个单光子纠缠态.通过使用分束器作用和对输出态进行光子测量以及在经典信息的帮助下,纠缠转移和量子隐形传态的过程被完成.

关键词：量子信息量子纠缠纠缠转移量子隐形传态