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Effects of Light Time, Light Intensity and Light Color on the Growth and Quality of Cordyceps militaris
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作者 Wei HUANG Niu CHENG +3 位作者 Han HE Daobo WANG Xujian CHEN Xiuying HUANG 《Asian Agricultural Research》 2020年第2期62-64,共3页
Cordyceps militaris,which is a precious edible fungus,contains effective ingredients such as cordycepin and adenosine,and can treat a variety of diseases.However,light has the greatest effect on the growth of C.milita... Cordyceps militaris,which is a precious edible fungus,contains effective ingredients such as cordycepin and adenosine,and can treat a variety of diseases.However,light has the greatest effect on the growth of C.militaris in the process of artificial cultivation.In this study,the effects of light time,light intensity and light color on the growth,physiology,yield and quality of C.militaris were discussed to provide reference for the efficient artificial cultivation of C.militaris. 展开更多
关键词 light time light INTENSITY light COLOR CORDYCEPS militaris QUALITY
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Consistent nighttime light time series in 1992–2020 in Northern Africa by combining DMSP-OLS and NPP-VIIRS data 被引量:1
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作者 Xiaotian Yuan Li Jia +1 位作者 Massimo Menenti Min Jiang 《Big Earth Data》 EI 2022年第4期603-632,共30页
Human activities modulate the impact of environmental forcing in general and of climate in particular.Information on the spatial and temporal patterns of human activities is in high demand,but scarce in sparsely popul... Human activities modulate the impact of environmental forcing in general and of climate in particular.Information on the spatial and temporal patterns of human activities is in high demand,but scarce in sparsely populated and data-poor regions such as Northern Africa.The intensity and spatial distribution of nighttime lights provide useful information on human activities and can be observed by space-borne imaging radiometers.Our study helps to bridge the gap between the DMSP-OLS data available until 2013 and the NPP-VIIRS data available since 2013.The approach to calibrate the OLS data includes three steps:a)inter-calibrate the OLS DN data acquired by different sensors in 1992-2013;b)cali-brate the OLS DN data using VIIRS data in 2013;c)generate syn-thetic OLS radiance data by degrading the VIIRS data in 2013-2020.We generated a)a time series of calibrated OLS nighttime light radiance data(1992-2013);b)mean annual VIIRS radiance on stable lights at the OLS spatial resolution for 2013-2020;c)synthetic OLS radiance data generated using VIIRS radiance data degraded to match the radiometric specifications of OLS for 2013-2020.The evaluation of these data products in 2013 documented their accu-racy and consistency. 展开更多
关键词 Nighttime light time series DMSP-OLS NPP-VIIRS median calibration model human activity northern equatorial Africa SAHEL
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Development of the real-time double-ring fusion neutron time-of-flight spectrometer system at HL-2M 被引量:3
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作者 Bo-Wen Zheng Wei Zhang +5 位作者 Tong-Yu Wu Si-Cheng Huang Yi-Po Zhang Xiu-Feng Xu Shi-Biao Tang Ze-Jie Yin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第12期22-30,共9页
A real-time double-ring neutron time-of-flight(TOFII) spectrometer system has been proposed to achieve plasma diagnosis on HL-2M tokamak with a relatively high count rate and sufficient energy resolution.The TOFII sys... A real-time double-ring neutron time-of-flight(TOFII) spectrometer system has been proposed to achieve plasma diagnosis on HL-2M tokamak with a relatively high count rate and sufficient energy resolution.The TOFII system is in its development stage,and this work describes its characteristics in terms of design principle,system structure,electronic system design,preliminary tests,and neutron transport simulation.The preliminary test results illustrate that the TOFII system can demonstrate the realtime dynamic spectrum every 10 ms.The results also show that based on the support vector machine method,the n-γ discrimination algorithm achieves the discrimination accuracy of 99.1%with a figure of merit of 1.30,and the intrinsic timing resolution of the system is within 0.3%.The simulated flight time spectrums from 1 to 5 MeV are obtained through the Monte Carlo tool Geant4,which also provide the reasonable results.The TOFII system will then be calibrated on mono-energetic neutron sources for further verification. 展开更多
关键词 time-of-light NEUTRON SPECTROMETER GEANT4 HL-2M
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Real-time Audio &Video Transmission System Based on Visible Light Communication 被引量:3
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作者 Yingjie He Liwei Ding +1 位作者 Yuxian Gong Yongjin Wang 《Optics and Photonics Journal》 2013年第2期153-157,共5页
With the increasing popularity of solid sate lighting devices, Visible Light Communication (VLC) is globally recognized as an advanced and promising technology to realize short-range, high speed as well as large capac... With the increasing popularity of solid sate lighting devices, Visible Light Communication (VLC) is globally recognized as an advanced and promising technology to realize short-range, high speed as well as large capacity wireless data transmission. In this paper, we propose a prototype of real-time audio and video broadcast system using inexpensive commercially available light emitting diode (LED) lamps. Experimental results show that real-time high quality audio and video with the maximum distance of 3 m can be achieved through proper layout of LED sources and improvement of concentration effects. Lighting model within room environment is designed and simulated which indicates close relationship between layout of light sources and distribution of illuminance. 展开更多
关键词 VISIBLE light Communications LED REAL-time Video and AUDIO BROADCAST System light Source Arrangement ILLUMINANCE Distribution
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USING TWO-DIMENSIONAL TIME RESOLVED LIGHT SCATTERING TO STUDY THE CURE REACTION INDUCED PHASE SEPARATION PROCESS OF EPOXY-AMINE-POLYETHERSULFONE BLEND WITH SECONDARY PHASE SEPARATION 被引量:1
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作者 唐晓林 张红东 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第1期63-68,共6页
The generalized two-dimensional correlation analysis based on time-resolved light scattering patterns (2D TRLS) has been employed to study the phase separation process of an epoxy-amine-polyethersulfone blend in whi... The generalized two-dimensional correlation analysis based on time-resolved light scattering patterns (2D TRLS) has been employed to study the phase separation process of an epoxy-amine-polyethersulfone blend in which the secondary phase separation takes place. The results of the 2D TRLS provided more detailed information that was not readily observed in the 1D TRLS patterns. (i) During the first process of phase separation, the sequential order of coarsening in size of the domains among the larger and smaller ones has been reversed between the diffusion regime and the hydrodynamic regime. (ii) The change of the larger domains in size, due to the hydrodynamic flow in the late stage of the first phase separation process, keeps on taking place earlier than that of the new domains appeared in the secondary phase separation process. (iii) During the secondary phase separation process the size growth of the smaller domains takes place earlier than that of the larger ones, probably due to the assumption that the coarsening mode could decrease the interface tension more quickly. 展开更多
关键词 Two-dimensional (2D) correlation analysis time-resolved light scattering (TRLS) Phase separation BLEND
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The Effect Density Has on the Speed of Light, Time, and the Dimensions of the Multiverse 被引量:1
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2022年第4期935-939,共5页
We show that as the dimensions of the Multiverse increase so does its density. This increase in density has the effect of decreasing the speed of light, slowing down time, and increasing the life span of each higher d... We show that as the dimensions of the Multiverse increase so does its density. This increase in density has the effect of decreasing the speed of light, slowing down time, and increasing the life span of each higher dimension and the life span of human beings occupying that higher dimension. We use the tenth dimension as the highest dimension as a special case but show that it is not possible to exactly determine its value because of varying factors that can end the Multiverse, sending all the Energy back into the original levels of the Quantum of the void that started the creation process. 展开更多
关键词 DENSITY GRAVITY time Speed of light Higher Dimensions
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Light Pollution Associated with Delayed Sleep Time: A Major Hygienic Problem in Saudi Arabia
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作者 Hussain Gadelkarim Ahmed Saleh Ahmed Alogla +4 位作者 Rayan Mohsen Ismael Abdulkarim Ali Alqufayi Saleh Othman Alamer Hamoud Khalid Alshaya Abdulsalam Eisa Mazyad Alshammari 《Journal of Behavioral and Brain Science》 2017年第3期125-136,共12页
Background: It was well established that exposure to nighttime light was responsible of a diverse negative health effect. Therefore, the aim of this study was to assess the epidemiologic exposure to artificial light a... Background: It was well established that exposure to nighttime light was responsible of a diverse negative health effect. Therefore, the aim of this study was to assess the epidemiologic exposure to artificial light at night time and negative health consequences that associated with prolonged nighttime lighting exposure. Methodology: This is a cross-sectional survey, involving a total of 266 Saudi residents living in the city of Hail, Northern KSA. Essential information regarding exposure to light at night time was obtained. Results: The overall incidence of nighttime light exposure in the present study was 65.8% for general population, was 61.5% males and was 38.5% for females. About 75.6% persons used to sleep for Conclusion: Prolonged exposure to the light at nighttime is prevalent in Saudi Arabia. This exposure usually results from late sleep in the nighttime and the late awake in the daytime. 展开更多
关键词 NIGHTtime SLEEP time light POLLUTION SAUDI ARABIA
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New approach for obtaining the time-evolution law of a chaotic light field in a damping gaining-process
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作者 龚黎华 周南润 +1 位作者 胡利云 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期31-33,共3页
A new approach for studying the time-evolution law of a chaotic light field in a damping-gaining coexisting process is presented. The new differential equation for determining the parameter of the density operator p(... A new approach for studying the time-evolution law of a chaotic light field in a damping-gaining coexisting process is presented. The new differential equation for determining the parameter of the density operator p(t) is derived and the solution of f for the damping and gaining processes are studied separately. Our approach is direct and the result is concise since it is not necessary for us to know the Kraus operators in advance. 展开更多
关键词 chaotic light field damping gaining process time evolution law quantum communication
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Phase Time of P-Polarized Light Pulses Passing through a Glass Plate
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作者 LI Chun-fang, HUANG Xin-hua, YAN Ai-min Department of physics, College of Sciences, Shanghai University Shanghai 200436, China 《Advances in Manufacturing》 SCIE CAS 2000年第S1期34-37,共4页
The phase time of p-polarized light pulses passing through a glass plate is investigated. We do this by converting the problem into a l-dimensional quantum-mechanical counterpart, a potential well with a position-depe... The phase time of p-polarized light pulses passing through a glass plate is investigated. We do this by converting the problem into a l-dimensional quantum-mechanical counterpart, a potential well with a position-dependent effective mass. We find that the phase time and the lateral shift have the negative characteristics. 展开更多
关键词 phase time potential well p-polarized light pulses
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A method to measure transit time spread of photomultiplier tubes with Cherenkov light
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作者 WU Chong DONG Huasong SUN Zhijia 《Nuclear Science and Techniques》 SCIE CAS CSCD 2009年第6期344-348,共5页
With the technology of coincidence method, transit time spreads (TTSs) of PMTs are measured with Cherenkov light on the photocathode window of photomultiplier tube (PMT) produced by cascade γ radiation source, 60Co. ... With the technology of coincidence method, transit time spreads (TTSs) of PMTs are measured with Cherenkov light on the photocathode window of photomultiplier tube (PMT) produced by cascade γ radiation source, 60Co. TTSs with single and multi-photoelectron which are analyzed by convolution of Poisson and Gaussian are obtained. The study to XP2020 and XP2020Q PMTs shows that TTSs are consistent with data supplied by Philips. TTSs are inversely proportional to the square roots of number of photoelectrons. The method is feasible when single and multi-photoelectron can be distinguished. 展开更多
关键词 光电倍增管 通过时间 并联机床 机床技术 钴-60 辐射源 PMT 卷积和
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Manpower Systems Operating under Heavy and Light Tailed Inter-Exit Time Distributions
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作者 R. Sivasamy P. Tirupathi Rao K. Thaga 《Applied Mathematics》 2014年第2期285-291,共7页
This paper considers a Manpower system where “exits” of employed personnel produce some wastage or loss. This system monitors these wastages over the sequence of exit epochs {t0 = 0 and tk;k = 1, 2,…} that form a r... This paper considers a Manpower system where “exits” of employed personnel produce some wastage or loss. This system monitors these wastages over the sequence of exit epochs {t0 = 0 and tk;k = 1, 2,…} that form a recurrent process and admit recruitment when the cumulative loss of man hours crosses a threshold level Y, which is also called the breakdown level. It is assumed that the inter-exit times Tk = tk-1 - tk, k = 1, 2,… are independent and identically distributed random variables with a common cumulative distribution function (CDF) B(t) = P(Tk t) which has a tail 1 – B(t) behaving like t-v with 1 v as t → ∞. The amounts {Xk} of wastages incurred during these inter-exit times {Tk} are independent and identically distributed random variables with CDF P(Xk X) = G(x) and Y is distributed, independently of {Xk} and {tk}, as an exponentiated exponential law with CDF H(y) = P(Y y) = (1 - e-λy)n. The mean waiting time to break down of the system has been obtained assuming B(t) to be heavy tailed and as well as light tailed. For the exponential case of G(x), a comparative study has also been made between heavy tailed mean waiting time to break down and light tailed mean waiting time to break down values. The recruitment policy operating under the heavy tailed case is shown to be more economical in all types of manpower systems. 展开更多
关键词 Manpower System Recruitment Policy Inter-Exit time Wastage Waiting time to Breakdown HEAVY TAILED Inter-Exit time Distribution and light TAILED Distribution
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白酒包装印刷品的耐光性研究
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作者 胡陈 杜娟 +5 位作者 梁艳 杨杰 卢振霞 姜育恒 刘星 黄敏 《包装工程》 北大核心 2026年第1期178-186,共9页
目的研究白酒包装印刷品在紫外光照射下的颜色变化,并在此基础上进行耐光性能预测。方法搜集4款18种常见酒包装印刷品,在氙灯耐气候试验箱下开展加速老化实验。用CIELAB和CIEDE2000色差值评价印刷品在不同老化时间下的耐光性。使用人工... 目的研究白酒包装印刷品在紫外光照射下的颜色变化,并在此基础上进行耐光性能预测。方法搜集4款18种常见酒包装印刷品,在氙灯耐气候试验箱下开展加速老化实验。用CIELAB和CIEDE2000色差值评价印刷品在不同老化时间下的耐光性。使用人工神经网络的方法预测酒包装产品在不同老化时间的光谱信息,进而预测其耐光性能。结果印刷品在紫外光照射下会出现颜色褪变现象,红色印刷品会变亮变淡,对应明度增加饱和度降低。来自不同印刷企业的同一款酒包装产品的颜色变化有较大差异,在本次实验的加速老化条件下,一般在90h后才出现不同产品的颜色变化。结论结果表明,训练样本的老化时间应不少于90h,才能进行样品的后期老化程度预测。实验结果也可为企业的印刷品油墨配方选取、光老化性能预测提供指导建议。 展开更多
关键词 白酒包装 印刷品 耐光性 色差 光老化时间
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应用SYBR GreenI的Real-time PCR方法定量检测空肠弯曲杆菌 被引量:10
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作者 阳成波 蒋原 +1 位作者 黄克和 祝长青 《动物医学进展》 CSCD 2003年第1期74-78,共5页
空肠弯曲杆菌(Campylobacterjejuni)被认为是人类主要食源性病原菌之一。由于空肠弯曲杆菌特殊的生长条件和容易进入不可培养但存活的状态(Viablebutnonculturable,VNC),所以传统的生化鉴定结果不一定可靠,并且是一项费时而繁琐的工作... 空肠弯曲杆菌(Campylobacterjejuni)被认为是人类主要食源性病原菌之一。由于空肠弯曲杆菌特殊的生长条件和容易进入不可培养但存活的状态(Viablebutnonculturable,VNC),所以传统的生化鉴定结果不一定可靠,并且是一项费时而繁琐的工作。核酸检测方法的出现为空肠弯曲杆菌的检测带来了方便。本文基于LightCycler为平台,利用SYBRGreenI染料能特异与双链DNA结合而发荧光的特性,建立一种Real-timePCR方法来定量检测空肠弯曲杆菌。用该方法检测时,发现所有空肠弯曲杆菌(11株)都呈阳性,所有其它弯曲菌(3株)和其它菌株(5株)都是阴性。整个检测过程60min内可以完成,检测限度为5CFU,标准曲线的相关系数为1。结果表明基于SYBRGreenI的定量PCR方法既为空肠弯曲杆菌提供了一种特异、敏感、快速和简洁的定量检测方法,又为研究空肠弯曲杆菌致病机理提供了一种重要方法。 展开更多
关键词 空肠弯曲杆菌 定量检测 SYBRGreenI染料 Real-timePCR方法 致病机理 食源性病原菌
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稀土掺杂钙钛矿超快闪烁体探测器实现亚纳秒时间分辨与吉赫兹级重频探测能力
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作者 陆彦宇 陈振华 +7 位作者 张增艳 郭智 邹鹰 刘海岗 杨帆 丁栋舟 王勇 邰仁忠 《物理学报》 北大核心 2026年第5期302-312,共11页
本文成功研制了一种基于稀土掺杂铯铅氯(CsPbCl3)无机闪烁晶体的新型高性能探测器.该晶体具备亚纳秒量级的荧光上升时间、纳秒级衰减时间及通过掺杂优化的高荧光产额.通过将其与具有亚纳秒级渡越时间的微通道板光电倍增管(MCP-PMT)及自... 本文成功研制了一种基于稀土掺杂铯铅氯(CsPbCl3)无机闪烁晶体的新型高性能探测器.该晶体具备亚纳秒量级的荧光上升时间、纳秒级衰减时间及通过掺杂优化的高荧光产额.通过将其与具有亚纳秒级渡越时间的微通道板光电倍增管(MCP-PMT)及自研的2.5 GHz高速采集系统集成,构建了一套完整的超快探测系统.基于光学分频的等效GHz激光脉冲测试表明,该系统能够清晰分辨平均峰值间隔仅0.79 ns的连续荧光脉冲,成功实现了1.26 GHz量级的高重频探测能力,在高速辐射探测领域展现出显著优势.在上海光源软X射线自由电子激光(SXFEL)装置中的实地应用表明,其X射线脉冲响应宽度窄至4 ns以下,远优于LYSO对比晶体,为超快时间分辨探测提供了可靠的技术方案. 展开更多
关键词 CsPbCl_(3)晶体 GHz 时间分辨率 光产额
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基于多时间尺度的HVDC Light系统降阶模型 被引量:1
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作者 王书征 李先允 陈小虎 《电网与清洁能源》 2010年第1期60-64,共5页
建立了基于dq同步旋转坐标系的轻型高压直流输电系统的状态空间模型,利用多时间尺度系统理论对模型进行了简化,分解出快慢子系统,并利用状态反馈,推导出基于多尺度模型的输出反馈控制策略,利用MATLAB进行仿真,并比较了简化前后模型的一... 建立了基于dq同步旋转坐标系的轻型高压直流输电系统的状态空间模型,利用多时间尺度系统理论对模型进行了简化,分解出快慢子系统,并利用状态反馈,推导出基于多尺度模型的输出反馈控制策略,利用MATLAB进行仿真,并比较了简化前后模型的一致性,仿真结果表明,简化后的模型具有良好的精确性。 展开更多
关键词 电压源型换流器(vsc) 轻型高压直流输电 多时间尺度 状态反馈
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基于PLO-FMD-Informer的智能电网数据安全隐患预测研究
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作者 万俊 刘志兴 +2 位作者 陈卫刚 李健 冯宇凯 《电气自动化》 2026年第2期89-92,共4页
随着电力系统数字化程度的不断提升,新型网络攻击方式层出不穷,传统安全防护机制在应对智能电网多维度安全威胁时逐渐显现出局限性。为此,提出了一种融合深度学习和信号处理技术的新型模型,名为PLO-FMD-Informer。首先,通过构建混合智... 随着电力系统数字化程度的不断提升,新型网络攻击方式层出不穷,传统安全防护机制在应对智能电网多维度安全威胁时逐渐显现出局限性。为此,提出了一种融合深度学习和信号处理技术的新型模型,名为PLO-FMD-Informer。首先,通过构建混合智能模型来有效识别和预警电网数据安全风险。接着通过特征模式分解对数据在频段和时间角度实施多尺度分解。而后,将这些精细化的特征输入改进的Informer编码器—解码器结构,并结合ProbSparse自注意力机制提取输入数据的长期依赖性和动态。试验结果表明,所提模型在真实电网数据集中的状态检测在精确率、召回率、F1分数和准确率方面均优于传统CNN-LSTM及其改进版本,为智能电网的主动安全防护提供了新范式。 展开更多
关键词 智能电网 安全隐患 Informer模型 特征模式分解 极光优化算法 时序分析
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Cryptochromes mRNA Expression Under Mating and Black light Treatment on Helicoverpa armigera
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作者 倪慧 闫硕 +1 位作者 刘小侠 张青文 《Plant Diseases and Pests》 CAS 2011年第3期20-23,30,共5页
[ Objective ] The paper was to confirm the effect of mating and black light treatment on cryptochromes mRNA expression of Hclicoverpa armigera. [ Method ] Quantitative real-time PCR ( SYBR Green) technique was appli... [ Objective ] The paper was to confirm the effect of mating and black light treatment on cryptochromes mRNA expression of Hclicoverpa armigera. [ Method ] Quantitative real-time PCR ( SYBR Green) technique was applied to detect the expression of cryptochromes gene ( cryl and cry2 ) of H. armigera under different conditions. Total RNA was extracted from the head of H. armigera, and carried out reverse transcription to synthesize cDNA after digested by DNase I. Specific primers were used to carry out quantitative real-time PCR on cryl, cry2 and EF-Ict gene, respectively. [ Result] The expression of cryl mRNA of H. ar- migera significantly decreased after exposure to black light for 2 h, the mRNA expression of cry2 was smaller than control, they had no significant difference with each other. Mating had significant effect on mRNA expression of cryl and cry2 of H. armigera, and the mRNA expression of cryl and cry2 of male and female adults showed decreasing trend with the prolongation of time after mating. [ Conclusion] The result had important significance for further studying on function of cry gene and the control of cotton bollwonn. 展开更多
关键词 Helicoverpa armigera cryl and cry2 Quantitative real-time PCR Black light MATING China
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2~12.5 MeV能区EJ301液体闪烁体探测器的光响应函数测量
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作者 刘颖一 阮锡超 +4 位作者 鲍杰 王金成 孙琪 任杰 吴鸿毅 《现代应用物理》 2026年第1期32-40,共9页
精确的光响应函数可为有机闪烁体中子探测器探测效率模拟提供关键输入参数。利用14.05 MeV的质子轰击Be靶,在0°方向产生能量范围为2~12.5 MeV连续中子,基于中国原子能科学研究院HI-13串列加速器的飞行时间谱仪,对Ф5.08 cm×5.... 精确的光响应函数可为有机闪烁体中子探测器探测效率模拟提供关键输入参数。利用14.05 MeV的质子轰击Be靶,在0°方向产生能量范围为2~12.5 MeV连续中子,基于中国原子能科学研究院HI-13串列加速器的飞行时间谱仪,对Ф5.08 cm×5.08 cm的EJ301液体闪烁体探测器的中子光响应函数进行了精确测量,系统能量分辨率优于5%。借助FLUKA模拟确定了^(137)Cs,^(207)Biγ射线的康普顿边缘位置,建立了光产额与等效电子能量之间的线性关系。采用电荷比较法实现n-γ脉冲形状甄别,有效剔除99%以上的γ本底。针对2~12.5 MeV能量范围的中子,以0.5 MeV间隔提取对应的脉冲高度分布,通过一阶导数与高斯拟合精确定位最大反冲质子边缘,得到反冲质子能量E_(p)与等效电子能量E_(e)的关系。分别使用Cecil和Kornilov提出的公式对光响应函数进行参数化拟合,给出了适用于Ф5.08 cm×5.08 cm的EJ301探测器解析表达式。该结果可直接用于蒙特卡罗模拟,为中子探测效率模拟提供可靠的数据支撑。 展开更多
关键词 液体闪烁体 EJ301 飞行时间 中子能谱 光响应
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复杂光照干扰下的结构光条纹中心提取方法
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作者 王漫琪 鲁大硕 孟祥翔 《激光与红外》 北大核心 2026年第3期381-386,共6页
为了解决高压软管内壁检测中传统算法难兼顾精度与实时性的问题,提出了一种复杂光照条件下快速、准确、实时的线结构光中心线提取的方法。采用高斯、中值滤波进行图像去噪,继而转换至HSV颜色空间,通过多区间阈值分割分离红色激光条纹与... 为了解决高压软管内壁检测中传统算法难兼顾精度与实时性的问题,提出了一种复杂光照条件下快速、准确、实时的线结构光中心线提取的方法。采用高斯、中值滤波进行图像去噪,继而转换至HSV颜色空间,通过多区间阈值分割分离红色激光条纹与高光区域;随后采用分区域自适应阈值处理与形态学优化,精确提取激光条纹的二值区域;接着经形态学优化后通过骨架化得到单像素宽的结构光条中心线;基于骨架化的点进行椭圆拟合,利用图像梯度计算法向量方向,并改进Steger算法实现亚像素级中心定位,实验表明,该算法在不同复杂光照背景下对红色激光条纹具有良好的提取能力,提取速度较传统steger算法提高了近五倍,提取精度与传统steger算法仅相差0.005像素,能够满足探测时高精度、实时性的要求。 展开更多
关键词 复杂光照 线结构光中心线提取 高精度 实时性 亚像素级
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基于夜间灯光数据的碳排放与土地利用效率时空相关性演进研究
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作者 邓因 王永超 杨可芯 《环境保护科学》 2026年第1期66-76,共11页
基于DMSP/OLS与NPP/VIIRS夜间灯光数据融合技术,反演并构建了285个地级市碳排放面板数据库,系统揭示了城市建设用地利用效率与碳排放的时空耦合机制。通过整合非期望产出超效率SBM模型、非参数核密度估计及双变量空间自相关分析方法,结... 基于DMSP/OLS与NPP/VIIRS夜间灯光数据融合技术,反演并构建了285个地级市碳排放面板数据库,系统揭示了城市建设用地利用效率与碳排放的时空耦合机制。通过整合非期望产出超效率SBM模型、非参数核密度估计及双变量空间自相关分析方法,结果表明:2000—2020年全国碳排放呈缓增态势,建设用地利用效率呈现“西部(0.823)>东北(0.718)>东部(0.694)>中部(0.681)”的空间分异格局;全局空间自相关检验表明两者存在显著负向关联,局部关联模式以L-L型(低效-低碳)、H-L型(高效-低碳)、L-H型(低效-高碳)为主导,H-H型(高效-高碳)集聚区占比不足12%;据此提出空间异质性调控策略:西部宜深化绿色能源枢纽功能,依托跨区域电力交易扩大清洁能源辐射范围;东部需构建产业-能源协同优化机制,通过技术创新降低单位用地能耗强度;东北与中部应建立产能置换-用地效率联动体系,在承接产业转移中实施用地碳效阈值管控。研究成果为协调国土空间开发与低碳转型目标提供了新的分析维度和政策工具。 展开更多
关键词 城市建设用地效率 超效率SBM模型 碳排放 时空相关性 夜间灯光
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