此前,我们曾到域丰音响位于广州番禺的陈列室中试听了naim最新推出的Uriiti Nova PE多功能一体机搭配Focal的Scala Utopia Evo落地式音箱,这套系统让笔者体验到了Uniti Nova PE的强劲推力,毕竟搭配Scala Utopia Evo属于越级挑战了。文...此前,我们曾到域丰音响位于广州番禺的陈列室中试听了naim最新推出的Uriiti Nova PE多功能一体机搭配Focal的Scala Utopia Evo落地式音箱,这套系统让笔者体验到了Uniti Nova PE的强劲推力,毕竟搭配Scala Utopia Evo属于越级挑战了。文章发布后也有读者朋友留言问到,naim Uniti Nova PE搭配和其价格相仿的Focal Sopra N°2会不会更好?于是我们再次来到域丰音响的试音室,试听这套系统的搭配。展开更多
Novae are found to have GeV to TeVγ-ray emission,which reveals the shock acceleration from the white dwarfs.Recently,V1405 Cas was reported to radiate suspiciousγ-ray by Fermi-LAT with low signi?cance(4.1σ)after th...Novae are found to have GeV to TeVγ-ray emission,which reveals the shock acceleration from the white dwarfs.Recently,V1405 Cas was reported to radiate suspiciousγ-ray by Fermi-LAT with low signi?cance(4.1σ)after the optical maximum.Radio observations reveal that it is one of the?ve brightest novae surrounded by low-density ionized gas columns.Here we report a continuous search for GeVγ-ray from Fermi-LAT.Noγ-ray was found.For V1405 Cas the?ux level is lower than other well-studied Fermi novae,and theγ-ray maximum appears at t0+145 days.γ-ray of V1405 Cas is used to search potentialγ-ray periodicity.Noγ-ray periodicity was found during the time of observation.By comparing multi-wavelength data,theγ-ray upper limit to optical?ux ratio with a value at around 10^(-4)is obtained to constrain the shock acceleration.Long-term analysis from Swift-XRT gets X-ray spectral in the post-shock phase,which indicates that V1405 Cas became a super-soft source.The best-?t black body temperature at the super soft state is 0.11-0.19 keV.展开更多
目前电厂烟囱变形监测主要利用传统测量或GPS技术,通过布置监测点达到监测的目的。但传统的监测方法容易受场地、天气、温度及风力等因素的影响,且观测周期较长。为此,进行快速高精度及无接触变形监测成为研究的热点。本文利用Leica Nov...目前电厂烟囱变形监测主要利用传统测量或GPS技术,通过布置监测点达到监测的目的。但传统的监测方法容易受场地、天气、温度及风力等因素的影响,且观测周期较长。为此,进行快速高精度及无接触变形监测成为研究的热点。本文利用Leica Nova MS50全站扫描仪高速点云扫描、高分辨率图像采集及长距离免棱镜测距的功能,进行烟囱倾斜及挠度变化的监测分析。展开更多
文摘此前,我们曾到域丰音响位于广州番禺的陈列室中试听了naim最新推出的Uriiti Nova PE多功能一体机搭配Focal的Scala Utopia Evo落地式音箱,这套系统让笔者体验到了Uniti Nova PE的强劲推力,毕竟搭配Scala Utopia Evo属于越级挑战了。文章发布后也有读者朋友留言问到,naim Uniti Nova PE搭配和其价格相仿的Focal Sopra N°2会不会更好?于是我们再次来到域丰音响的试音室,试听这套系统的搭配。
基金supported by the National Natural Science Foundation of China(NSFC,grant No.12393853)the Scientific Research Foundation of Hunan Provincial Education Department(21C0343)+1 种基金the Science Research Project of the University(Youth Project)of the Department of Education of Guizhou Province(QJJ[2022]348)the Science and Technology Foundation of Guizhou Province(QKHJC-ZK[2023]442)。
文摘Novae are found to have GeV to TeVγ-ray emission,which reveals the shock acceleration from the white dwarfs.Recently,V1405 Cas was reported to radiate suspiciousγ-ray by Fermi-LAT with low signi?cance(4.1σ)after the optical maximum.Radio observations reveal that it is one of the?ve brightest novae surrounded by low-density ionized gas columns.Here we report a continuous search for GeVγ-ray from Fermi-LAT.Noγ-ray was found.For V1405 Cas the?ux level is lower than other well-studied Fermi novae,and theγ-ray maximum appears at t0+145 days.γ-ray of V1405 Cas is used to search potentialγ-ray periodicity.Noγ-ray periodicity was found during the time of observation.By comparing multi-wavelength data,theγ-ray upper limit to optical?ux ratio with a value at around 10^(-4)is obtained to constrain the shock acceleration.Long-term analysis from Swift-XRT gets X-ray spectral in the post-shock phase,which indicates that V1405 Cas became a super-soft source.The best-?t black body temperature at the super soft state is 0.11-0.19 keV.
文摘目前电厂烟囱变形监测主要利用传统测量或GPS技术,通过布置监测点达到监测的目的。但传统的监测方法容易受场地、天气、温度及风力等因素的影响,且观测周期较长。为此,进行快速高精度及无接触变形监测成为研究的热点。本文利用Leica Nova MS50全站扫描仪高速点云扫描、高分辨率图像采集及长距离免棱镜测距的功能,进行烟囱倾斜及挠度变化的监测分析。