Preliminary Study of Photometric Redshifts Based on the Wide Field Survey Telescope

The Wide Field Survey Telescope(WFST)is a dedicated time-domain multi-band(u,g,r,i,and z)photometric survey facility under construction.In this paper,we present a preliminary study that assesses the quality of photometric redshifts based on WFST by utilizing mock observations derived with the galaxy catalog in the COSMOS/UltraVISTA field.We apply the template fitting technique to estimate photometric redshifts by using the ZEBRA photometric-redshift code and adopting a modified set of adaptive templates.We evaluate the bias(median relative offset between the output photometric redshifts and input redshifts),normalized median absolute deviation(σ_(NMAD))and outlier fraction(f_(outlier))of photometric redshifts in two typical WFST observational cases,the single 30 s exposure observations(hereafter shallow mode)and co-added 50 minutes exposure observations(hereafter deep mode).We find bias≲0.006,σ_(NMAD)≲0.03,and f_(outlier)≲5%in the shallow mode and bias≈0.005,σ_(NMAD)≈0.06,and f_(outlier)≈17%–27%in the deep mode,respectively,under various lunar phases.Combining the WFST mock observational data with that from the upcoming CSST and Euclid surveys,we demonstrate that the zphot results can be significantly improved,with f_(outlier)≈1%andσ_(NMAD)≈0.02.

紫外分光光度法测定电镀锡板表面涂油量

涂油量是电镀锡板产品关键指标之一。通过对有机萃取剂、吸收波长、校准曲线等研究,建立了紫外光度法测定电镀锡板表面涂油量检测方法。选择正庚烷作为有机萃取剂,吸收波长为270 nm,油质量浓度在10.00~100.00 mg/L范围内,吸光度与涂油质量呈线性关系,线性回归方程为y=121.710 x+0.965。应用该方法检测电镀锡板表面涂油量,检测结果相对标准偏差为-2.81%~2.57%%,加标回收实验回收率为97.2%~103.2%。该方法与重量法比对,检测结果无显著性差异,完全满足电镀锡板表面涂油量指标监控要求。

搜寻第二个地球——系外地球(ET)巡天计划

系外地球科学卫星(ET)将通过采用空间大视场超高精度测光这一关键技术在国际上率先突破生命起源中的系外地球存在及其演化这一重大前沿科学问题. ET卫星将在日地拉格朗日L2点晕(Halo)轨道部署由6台广角凌星望远镜和1台微引力透镜望远镜构成的空间天文台,结合凌星法和微引力透镜法,利用空间超大视场和超高精度的光学测光观测,首次发现富有重要意义、被广泛关注的系外地球,并确定其发生率,对目前了解甚少的类地行星和流浪行星进行国际上第一次大规模的种群普查,首次发现流浪地球,并确定其发生率,揭示类地行星和流浪行星起源,为地外生命探寻提供候选者和新方向. ET卫星的观测结果、统计研究以及和对理论的检验将回答系外地球在宇宙中有多普遍,类地行星是如何形成和演化的,流浪行星又是如何起源的这些亟待解决的前沿科学问题.对ET卫星发现的系外地球样本的后随观测,将精确测量其质量、密度和大气成分,有助于深入分析宜居性特征.此外,对ET新发现的大量各种系外行星样本的研究,以及对理论的检验将推动这些种类的行星形成和演化规律的更深入认识, ET的大量高精度、高频次和长基线测光数据将推动星震学、银河系考古学、时域天文学、双星和双星黑洞等领域的研究.

近场分布式光度计的研究进展及应用

亮度计成像精度、存储器数据容量和计算机运算能力决定了近场分布式光度计的探测能力。随着成像技术和计算机技术的发展,近场分布式光度计的测量性能有了革命性的提升。介绍了近场分布式光度计的工作原理,归纳了近场分布式光度计相对于远场分布式光度计的优势。综述了国内外近场分布式光度计的研究进展,对比了部分国内外产品的性能指标。针对近场分布式光度计元数据精度不足、扫描重构速度偏慢和溯源装置适应性受限的现状,从部件、软件和系统等方面归纳了相应的解决方案。结合近场分布式光度计的特点和优势,展望了其在照明显示、交通运输、工业视觉和文物保护等领域的应用。

基于反射光度法的干化学检测技术的研究

针对反射光度法的干化学检测中,因检测样品反射光信号的发散和多层膜干片试纸内部存在多重内反射,导致检测稳定性和准确性不足的问题,设计了一种基于积分球的干化学反射光度法检测系统。首先,增设积分球装置,可减少信号的发散与流失并均匀检测样品的反射光信号,提高检测的稳定性;其次,进行Light Tools光学仿真分析,并建立积分球检测模型;再次,基于Williams-Clapper方程对多重内反射导致的反射密度的误差进行修正以提高检测的准确性。实验验证:所开发的基于积分球的干化学反射光度法检测系统提高了检测系统的稳定性和准确性。

Close Major-merger Pairs at z=0: Star-forming Galaxies with Pseudobulges

We present a study of star-forming galaxies (SFGs) with pseudobulges (bulges with Sérsic index n<2) in a loca close major-merger galaxy pair sample (H-KPAIR).With data from new aperture photometries in the optical and near-infrared bands (aperture size of 7 kpc) and from the literature,we find that the mean Age of central stellar populations in Spirals with pseudobulges is consistent with that of disky galaxies and is nearly constant against the bulge-to-total ratio (B/T).Paired Spirals have a slightly lower fraction of pure disk galaxies (B/T≤0.1) than their counterparts in the control sample.Compared to SFGs with classical bulges,those with pseudobulges have a higher (>2σ) mean of specific star formation rate (sSFR) enhancement (sSFR_(enh)=0.33±0.07 versus sSFR_(enh)=0.12±0.06) and broader scatter (by~1 dex).The eight SFGs that have the highest sSFR_(enh)in the sample all have pseudobulges.A majority (69%) of paired SFGs with strong enhancement (having sSFR more than5 times the median of the control galaxies) have pseudobulges.The Spitzer data show that the pseudobulges in these galaxies are tightly linked to nuclear/circum-nuclear starbursts.Pseudobulge SFGs in S+S and in S+E pairs have significantly (>3σ) different sSFR enhancement,with the means of sSFR_(enh)=0.45±0.08 and-0.04±0.11respectively.We find a decrease in the sSFR enhancements with the density of the environment for SFGs with pseudobulges.Since a high fraction (5/11) of pseudobulge SFGs in S+E pairs are in rich groups/clusters (loca density N_(1Mpc)≥7),the dense environment might be the cause for their low s SFR_(enh).

催化动力学光度法测定痕量亚硝酸根

在冰乙酸介质中,利用亚硝酸根催化条件下,溴酸钾氧化茜素红的褪色反应,建立催化动力学光度法,对痕量NO_(2)^(-)进行测定.通过单因素实验得到了各种成分的加入量、反应温度和反应时间等最佳条件.结果发现,在反应体系中,茜素红浓度与NO_(2)^(-)含量之间线性关系良好,在0.02~0.14μg/mL范围内,线性回归方程为ln(A_(0)/A)=1.43 c NO_(3)^(-)(μg/mL)+0.00859,相关系数r^(2)为0.9970,检出限为5.25×10^(-3)μg/mL.该方法操作简单、稳定性好.

Increased excitatory amino acid transporter 2 levels in basolateral amygdala astrocytes mediate chronic stress–induced anxiety-like behavior

The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with emotions.Specifically, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal mice.After knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was obviously mitigated. Additionally, administration of an excitatory amino acid transporter 2 inhibitor in the basolateral amygdala yielded a notable reduction in anxiety level among mice subjected to stress. These results suggest that basolateral amygdala astrocytic excitatory amino acid transporter 2 plays a role in in the regulation of unpredictable chronic mild stress-induced anxiety-like behavior by impacting the activity of local glutamatergic neurons, and targeting excitatory amino acid transporter 2 in the basolateral amygdala holds therapeutic promise for addressing anxiety disorders.

GIS盆式绝缘子表面微弱放电的光学检测方法研究

气体绝缘全封闭式组合电器(gas insulated switchgear,GIS)是电力系统不可缺少的电气设备,但目前对于其盆式绝缘子表面微弱缺陷放电仍缺乏可靠的监测手段。光测法作为非电检测手段在GIS内部弱光环境下对放电具有较好的检测效果。该文首先利用LED光源验证光路追迹仿真的准确性;其次以仿真作为基础,以试验作为依托研究了GIS内部绝缘子表面缺陷放电光信号随距离变化的传播规律,提出了检测GIS内部微弱放电时光学传感器的要求和布置方法;最后探索光测法对于微弱放电信号的检测灵敏度。研究结果表明:光路追迹仿真与LED光源试验呈现相同规律,其最大误差小于10%;绝缘子正面与侧面缺陷放电光信号随传感器布置距离增大具有明显的衰减规律,而背面缺陷放电光信号不具有衰减规律;光学传感器检测时其对波长的要求为300~550nm,其最小检测光强应大于1.43×10-11W,响应时间应小于局部放电单次脉冲时间;布置在GIS内壁中部的光电倍增管对盆式绝缘子表面不同位置缺陷的检测效果最佳;对于微弱放电的检测光测法灵敏度高于脉冲电流法。该文研究结论对光学传感器应用于检测GIS内部缺陷放电具有参考价值。

不同余氯监测仪在泳池水中的应用研究

构建泳池水循环系统以模拟现场余氯监测,以哈希便携式余氯仪的测量值为基准,比较恒压式余氯传感器、隔膜式余氯传感器和DPD比色法在线监测仪的测量结果,找出最适合应用于泳池水余氯在线监测的仪表,并研究了导致3种余氯在线监测仪测量结果差异性的因素。结果表明,DPD比色法在线监测仪在测量准确性及稳定性上表现最好,最适合应用于泳池水余氯在线监测。泳池水中存在的结合氯引起恒压式余氯传感器测量结果偏高,水样高浊度引起隔膜式余氯传感器的测量稳定性变差。

Upgraded photometric system on the 85-cm telescope at Xinglong station

The 85-cm telescope at Xinglong station is a prime focus system that operates well with high science outputs. The telescope has been upgraded since 2014 with a new corrector, and new filters and camera, which are provided by Beijing Normal University. The filter set is the Johnson-Cousins UBV RI system. We report the test results of the new system including bias, dark current, linearity, gain and readout noise of the CCD camera. Then we derive accurate instrumental calibration coefficients in UBV RI bands with Landolt standard stars during photometric nights. Finally, we give the limiting magnitudes with various exposure times and signal-to-noise ratios for observers as references.

Inductively coupled plasma emission spectroscopic and flame photometric analysis of goat epididymal fluid

Aim: The elemental composition of the epididymal luminal fluid (ELF) in adult goat ( Capra indica) was investigat-ed. Methods: ELF was collected by micropuncture from twelve sites along the epididymal duct. The elementalcontents was analyzed with inductively coupled plasma (ICP) emission spectroscopy, a microanalytical technique thatcan simultaneously measure many elements in minute volumes of sample. The Na and K concentrations were determinedby flame photometry. Results: ICP spectroscopy showed the presence of copper, calcium, nickel, iron, magne-sium, chromium, titanium and zinc in ELF, with fluctuating levels at different sites along the length of the epididymis.Cadmium, cobalt, lead and manganese were not fotmd. The Na^+ / K^+ ratio was seen to be higher at the initial seg-ments of the epididymis and lower at the distal. Conclusion: It is proposed that the observed characteristic distribu-tion of elements in ELF may have far reaching implications in sperm maturation and storage known to occur in the epi-didymis. (Asian J Androl 2000 Dec; 2: 288-292)

The wide-field photometric system of the Nanshan One-meter Telescope

The Nanshan One-meter Wide-field Telescope is a prime focus system that is located at Nanshan Station of Xinjiang Astronomical Observatories.The field of view was designed to 1.5°× 1.5°,and the Johnson-Cousins UBVRI system was chosen as the main filter set.The telescope has been providing observation services for astronomers since September 2013.Variable source searching and time-domain surveys are the main scientific goals.The system’s test results are reported including linearity,dark current,bias,readout noise and gain of the CCD camera.The accurate instrumental calibration coefficients in UBVRI bands were driven with Landolt standard stars during photometric nights.Finally,the limiting magnitudes are given with signal-to-noise ratios and various exposure times for observers.

Photometric Survey of Galactic Open Clusters

We present a progress of a long term project to obtain UBVI CCD photometry of open clusters which were little studied before, using the Doyak 1.8 m telecope of Bohyunsan Optical Astronomy Observatory operated by the Korea Astronomical Observatory, in Korea. The primary goals of this project are (1) to make a catalog of UBVI photometry of open clusters, (2) to make an atlas of open clusters, and (3) to survey and monitor variable stars in open clusters.

Charge coupled devices （CCD） photometry and long-term optical variability of gamma-ray-loud BL Lacertae object Mkn 421

Evidence for the long-term optical curve variability and colour behaviour of the BL Lac object Mkn 421 is presented. Our results show that the amplitude of the optical variations of Mkn 421 is only about △B=4.7 magnitude in the B-band for its photometric history from 1899 to 2002. The results of optical photometric monitoring of the Mkn 421 from April 2000 to Jan 2002 are provided. During our observation, Mkn 421 shows significant rapid variations and exhibits short time variability of 2.42 hours in the B band. A strong correlation between the B - V colour index and the magnitude in the B band is found. Our charge coupled device （CCD） photometry of Mkn 421 shows that the measured results are in good agreement with the predicted optical variability period of about 23 years.

All-fiber-transmission photometry for simultaneous optogenetic stimulation and multi-color neuronal activity recording

Manipulating and real-time monitoring of neuronal activities with cell-type specificity and precise spatiotemporal resolution during animal behavior are fundamental technologies for exploring the functional connectivity, information transmission, and physiological functions of neural circuits in vivo. However, current techniques for optogenetic stimulation and neuronal activity recording mostly operate independently. Here, we report an all-fiber-transmission photometry system for simultaneous optogenetic manipulation and multi-color recording of neuronal activities and the neurotransmitter release in a freely moving animal. We have designed and manufactured a wavelength-independent multi-branch fiber bundle to enable simultaneous optogenetic manipulation and multi-color recording at different wavelengths. Further, we combine a laser of narrow linewidth with the lock-in amplification method to suppress the optogenetic stimulation-induced artifacts and channel crosstalk. We show that the collection efficiency of our system outperforms a traditional epi-fluorescence system. Further, we demonstrate successful recording of dynamic dopamine(DA) responses to unexpected rewards in the nucleus accumbens(NAc) in a freely moving mouse. We also show simultaneous dual-color recording of neuronal Ca2+ signals and DA dynamics in the NAc upon delivering an unexpected reward and the simultaneous optogenetic activating at dopaminergic terminals in the same location. Thus, our multi-function fiber photometry system provides a compatible, efficient, and flexible solution for neuroscientists to study neural circuits and neurological diseases.

In vivo fiber photometry of neural activity in response to optogenetically manipulated inputs in freely moving mice

In vito fber photometry is a powerful technique to analyze the dy namics of population neurons during fiunctional study of neuroscience.Here,we introduced a detailed protocol for fiber photometry-based calciun reording in freely moving mice,covering from virus injection,fiber stub insertion,optogenetical stimulation to data procurement and analysis.Furthemnore,we applied this protocol to explore neuronal activity of mice latenal-posterior(LP)thalaric nucleus in response to optogenetical stimulation of primary visual cortex(V1)neurons,and explore axon clusters activity of optogenetically evoked V1 neurons.Final confirmation of virus-based protein expression in V1 and precise fber insertion indicated that the surgery procedure of this protocol is reliable for functional calcium recording.The scripts for data analysis and some tips in our protocol are provided in details.Together,this protocol is simple,low-cost,and effective for neuronal activity detection by fiber photometry,which will hep neuroscience researchers to carry out fiunctional and behavioral study in vivo.

The Simultaneous Three-channel Multicolor CCD Photometric System of the 1.2 m Telescope at Jilin Astronomical Observatory

We will introduce the construction and design of a new simultaneous three-channel multicolor CCD photometer.This photometer has been mounted on the 1.2 m telescope at Jilin Astronomical Observatory,and is applied to study space debris,gamma-ray burst afterglows,asteroids and other rapidly variable objects.As one of the ground follow-up telescopes of the Chinese-French Space-based multi-band astronomical Variable Objects Monitor(SVOM)mission,it appears very essential to evaluate the performance of the photometry system of this photometer,which can achieve simultaneous imaging within a field of view of 21’.5×21’.5,21’.5×21’.5 and21’.3×21’.3 in the Sloan Digital Sky Survey(SDSS)g’,r’,i’bands,respectively.Photometric calibrations were carried out by using plenty of SDSS standard stars,and the relationship between the photometric system and the Johnson-Bessel filter system was also studied.The results of the performance evaluation from observing open cluster M67 are presented.

Co-colouration Effects in the Systems of Metal(Ⅱ)-Rare Earth(Ⅲ)-Xanthene Dye and Their Influences on Photometric Determination of Metal Ions

After comparing the influences of each rare earth(Ⅲ),11 species of metal(Ⅱ)and 8 species of acidic triphenylmethane dye on the formation of coloured coordination compound in the system of Metal(Ⅱ)-RE (Ⅲ)-Dye,it was proven that the co-colouration effect can be caused only by the xanthene dyes(XD)con- taining substituting hydroxy.group on the ortho-position of etheric oxygen group.Besides,the radius of met- al(Ⅱ)must not be smaller than a definite limit;otherwise,no co-colouration appears.Furthermore,the acid- ity of medium is another important factor to affect co-colouration,Bromopyrogallol red causes co-colouration of Pb(Ⅱ)-RE(Ⅲ)only,owing to its higher chromophoric acidity;while alizarin violet causes co-colouration of M(Ⅱ)-RE(Ⅲ)(M=Pb,Ca,Sr and Ba),due to its lower chromophoric acidity.The condi- tions causing co-colouration,the regularities of co-colouration and the influences of co-colouration in photometric determination of metals were discussed.

Extraction-spectrophotometric Determination of Dicyanoaurate(Ⅰ) with Crystal Violet

Extraction spectrophotometric determination of dicyanoaurate (Ⅰ) with Crystal Violet is described. At pH 2.6～10.7, dicyanoaurate (Ⅰ) can react with Crystal Violet and form a complex which can be extracted into isoamylacetate. The apparent molar absorptivity is 8.37×10 4 L·mol -1 ·cm -1 at 605 nm. Beer′s law is obeyed for 0～15 μg of Au(Ⅰ) per 5 ml of isoamylacetate. The interference from Ag(Ⅰ) and Cu(Ⅱ) can be eliminated with thiourea and EDTA. The method is applied to the determination of dicyanoaurate (Ⅰ) in sample solution with satisfactory results.