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Development of a high-speed digital pulse signal acquisition and processing system based on MTCA for liquid scintillator neutron detector on EAST

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Nuclear Science and Techniques 2023年第10期34卷 60-72页

作者： Yong-qiang Zhang Li-Qun Hu guo-qiang Zhong hong-Rui Cao Jin-Long Zhao Li Yang qiang Li Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Institute of Energy Hefei Comprehensive National Science CenterHefei 230031China

In this experimental study, involving deuterium–deuterium fusion neutron emission spectroscopy measurement on the experimental advanced superconducting tokamak(EAST), a liquid scintillator detector(BC501 A) was employed. This decision was based on the detector's superior sensitivity, optimal time-response, and its exceptional n–γ discrimination capability. This detector emits fast pulse signals that are as narrow as 100 ns, with high count rates that can peak at several Mcps. However, conventional nuclear circuits faced challenges in performing pulse height analysis, n–γ pulse shape discrimination, and in recording the entire pulse waveform under such high count rate conditions. To address these challenges, a high-speed digital pulse signal acquisition and processing system was designed. The system was developed around a micro-telecommunications computing architecture. Within this structure, a signal acquisition and processing(SAQP) module communicated through PCI Express links, achieving a bandwidth of up to 1.6 GB/s. To accurately capture the detailed shape of the pulses, four channels of analog-to-digital converters were used, each with a 500-MSPS sampling rate and a 14-bit resolution, ensuring an accuracy that surpassed 11 bits. An n–γ discrimination algorithm, based on the two-gate integral method, was also developed. Implemented within field programmable gate arrays, this algorithm provided a real-time n–γ discrimination spectrum for pulse height analysis. The system underwent rigorous testing in a laboratory setting and during an EAST experiment. The results confirmed that the innovative SAQP system can satisfy the demanding requirements of high-parameter experiments, manage count rates of up to 2 Mcps, execute real-time n–γ discrimination algorithms, and record entire pulse waveforms without any data loss.

关键词： EAST NES High-speed MTCA n–γdiscrimination Entire pulse waveform

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泡沫混凝土填充双箭头结构的准静态压缩性能

复合材料学报 2025年第1期42卷 403-414页

作者：周宏元郭春燕王小娟张宏北京工业大学城市与工程安全减灾教育部重点实验室北京100124 北京理工大学爆炸科学与安全防护全国重点实验室北京100081

为提高三明治结构的力学和能量吸收性能,提出一种泡沫混凝土填充双箭头结构。制作双箭头结构并填充不同强度的低密度泡沫混凝土,通过试验得到准静态压缩下填充泡沫混凝土双箭头结构的变形模式、力学性能和能量吸收性能,并使用经试验验... 详细信息

为提高三明治结构的力学和能量吸收性能,提出一种泡沫混凝土填充双箭头结构。制作双箭头结构并填充不同强度的低密度泡沫混凝土,通过试验得到准静态压缩下填充泡沫混凝土双箭头结构的变形模式、力学性能和能量吸收性能,并使用经试验验证的数值模型进一步分析了胞壁厚度与泡沫混凝土强度、胞元角度等重要因素对此填充结构压缩性能的影响。结果表明:双箭头结构可约束泡沫混凝土,双箭头结构和泡沫混凝土的合理匹配可有效利用两者间的相互作用,优化能量吸收性能。泡沫混凝土填充双箭头结构平均压缩强度的增量随填充泡沫混凝土强度的升高而升高,胞壁厚度为0.2 mm时,填充强度为0.46 MPa泡沫混凝土的结构比吸能最大;胞壁厚度为0.4 mm时,填充强度为1.02 MPa泡沫混凝土的结构比吸能最大。增加胞壁厚度可提高平均压缩强度的增量,提高比吸能。调整胞元角度,可实现对平均压缩强度增量和比吸能的调控。

关键词：泡沫混凝土双箭头结构负泊松比准静态压缩变形模式能量吸收

形变热处理对Incoloy 800合金组织及耐腐蚀性能的影响

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塑性工程学报 2025年第1期32卷 228-234页

作者：江鸿刘航强雨霖张子旭上海理工大学材料与化学学院上海200093

以95%冷轧获得的纳米晶Incoloy 800合金为对象,研究了不同退火温度下纳米晶材料的微观组织及在模拟Cl-的腐蚀环境中电化学腐蚀行为。结果表明:冷轧态合金微观组织得到显著细化,500℃退火后合金得到初步回复,温度升高至600℃晶界变得清晰... 详细信息

以95%冷轧获得的纳米晶Incoloy 800合金为对象,研究了不同退火温度下纳米晶材料的微观组织及在模拟Cl-的腐蚀环境中电化学腐蚀行为。结果表明:冷轧态合金微观组织得到显著细化,500℃退火后合金得到初步回复,温度升高至600℃晶界变得清晰,同时出现析出相TiC及Cr_(23)C_(6)。700℃退火后合金发生明显的再结晶,析出相Cr_(23)C_(6)大量增加,弥散分布于基体。冷轧态Incoloy 800合金耐腐蚀性能最好,高密度位错为表面钝化膜的形成提供位点,进入活化阶段钝化膜能降低腐蚀速率。其中,600℃退火合金相较其他温度的耐腐蚀性能较好。700℃退火后,Cr_(23)C_(6)相大量析出,耐腐蚀性能最差。

关键词： Incoloy 800合金形变热处理微观组织耐腐蚀性

Nutrient Deficiency Affects Root Architecture of Young Seedlings of Malus hupehensis (Pamp) Rehd. Under Conditions of Artificial Medium Cultivation

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Agricultural Sciences in China 2007年第3期6卷 296-303页

作者： FAN Wei-guo YANG hong-qiang College of Horticulture Science and Engineering Shandong Agricultural University Taian 271018 P.R.China

What the researchers go in for is to establish models between root architecture （RA） changes and nutrition, mold ideal root architecture of apple trees, improve the nutrient uptake efficiency, and further explore the functional mechanism of nutrient elements during the course of RA construction. The cultivation system of filter paper is utilized to research the effect of nutrient deficiency on the RA of Malus hupehensis （Pamp.） Rehd. There may be eight types of RA. In complete Hogland solution, the main type of RA is ＂lateral roots clustering in the upper and middle regions of primary root＂. With the lack of P, K or Ca, the main type of RA is ＂lateral roots clustering in the upper region primary root＂, and the ＂lateral roots clustering in the upper and middle regions of primary root＂ types of RA decrease. But with shortage of P, the type of lateral roots clustering in the upper and lower regions of primary root increases, and the type of lateral roots clustering in the middle region of primary root decreases, with the types of RA diversified. Under the condition of K deficiency, the type of no lateral root increases and types of lateral roots clustering in the middle region of primary root decrease, and the percentage of such types as ＂no lateral root＂, ＂lateral roots clustering in the upper region of primary root＂, and ＂lateral roots clustering in the upper and middle regions of primary root＂ accounts for 97.9% in all, with the types of RA simplified. With lack of Fe, Mg or Zn, the main type of RA is ＂lateral roots clustering in the upper and middle regions of primary root＂, but the type of lateral roots evenly-distributed on primary root increases. The main type of RA is ＂lateral roots evenlydistributed on primary root＂, under the condition of N deficiency, and the types of RA turn out to be diversified. There exists a close relation between nutrient deficiency and RA changes. Owing to various forms of nutrient deficiency, correspondingly different types of RA hav

关键词： Malus hupehensis (Pamp.) Rehd. paper-culture root architecture (RA) nutrient deficiency

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农安油页岩热重及热物理性质试验研究

世界地质 2016年第4期35卷 1178-1184页

作者：周科孙友宏李强郭威吕士东韩婧吉林大学建设工程学院长春130026

对吉林农安油页岩进行了TG分析,发现在N2气氛下其热失重可分为低温失重段（30℃-300℃）、中温失重段（300℃-540℃）和高温失重段（540℃-800℃）,且中温失重段为主要失重阶段。对农安油页岩进行了热物理性质试验,发现其热物理性质具... 详细信息

对吉林农安油页岩进行了TG分析,发现在N2气氛下其热失重可分为低温失重段（30℃-300℃）、中温失重段（300℃-540℃）和高温失重段（540℃-800℃）,且中温失重段为主要失重阶段。对农安油页岩进行了热物理性质试验,发现其热物理性质具有各向异性,且水平层理方向的热物理性质系数更大;导热系数和体积比热容随温度升高变化趋势一致,而热扩散系数随温度升高变化不大。

关键词：油页岩热重实验导热系数热扩散系数比热容农安

钙生境对紫花苜蓿种子萌发生长特性影响及其耐钙综合评价研究

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草地学报 2025年第1期33卷 157-169页

作者：万晓梅杭红涛张运飞郭国玲贵州师范大学喀斯特研究院贵州贵阳550001 国家喀斯特石漠化防治工程技术研究中心贵州贵阳550001

为筛选出耐钙胁迫的紫花苜蓿(Medicago sativa)品种,本研究选取14个紫花苜蓿品种作为试验材料,配制不同Ca^(2+)浓度的霍格兰营养液模拟钙生境进行种子萌发试验,通过测定发芽指标、形态指标、生物量指标,基于隶属函数法综合评价紫花苜蓿... 详细信息

为筛选出耐钙胁迫的紫花苜蓿(Medicago sativa)品种,本研究选取14个紫花苜蓿品种作为试验材料,配制不同Ca^(2+)浓度的霍格兰营养液模拟钙生境进行种子萌发试验,通过测定发芽指标、形态指标、生物量指标,基于隶属函数法综合评价紫花苜蓿品种间种子萌发期的耐钙性。结果表明:在0~320 mmol∙L^(-1)钙浓度下,大多数紫花苜蓿品种的发芽率、胚芽长等指标随钙浓度提高先略微上升后呈下降趋势,且钙浓度越高下降幅度越大,其中在120 mmol∙L^(-1)钙浓度下各品种间发芽率产生显著差异(P<0.05),可视为拐点浓度;最适宜的发芽浓度为0.4~4 mmol∙L^(-1),半致死浓度为120~160 mmol∙L^(-1),致死浓度为160~200 mmol∙L^(-1)。通过聚类分析将14个品种的抗钙能力划分为5个类群。基于隶属函数综合评价结果筛选出耐钙能力最强的品种为‘WL525HQ’,最弱的为‘WL656HQ’。研究结果表明紫花苜蓿‘WL525HQ’品种在高钙胁迫下具有较强的耐钙性和生存能力,建议将该品种作为岩溶区紫花苜蓿牧草种植推广的首选品种。

关键词：紫花苜蓿岩溶钙生境种子萌发耐钙评价

β-Pb3P2S8: A new optical crystal with exceptional birefringence effect

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Chinese Chemical Letters 2025年第2期36卷 514-517页

作者： Weiping guo Ying Zhu hong-Hua Cui Lingyun Li Yan Yu Zhong-Zhen Luo Zhigang Zou Key Laboratory of Eco-materials Advanced Technology Key Laboratory of Advanced Materials Technologies International (HongKong Macao and Taiwan) Joint Laboratory on Advanced Materials Technologies College of Materials Science and Engineering Fuzhou University Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China Mechanical and Electrical Engineering Practice Center Fuzhou University Eco-materials and Renewable Energy Research Center College of Engineering and Applied Sciences Nanjing University

Birefringent crystals play an irreplaceable role in optical systems by adjusting the polarization state of light in optical *** work successfully synthesized a new thiophosphate phase of β-Pb3P2S8through the high-temperature solid-state spontaneous crystallization *** from the cubicα-Pb3P2S8,the β-Pb3P2S8crystallizes in the orthorhombic Pbcn space ***,β-Pb3P2S8shows a large band gap of 2.37 e V in lead-based chalcogenides,wide infrared transparent window （2.5-15μm）,and excellent thermal ***,the experimental birefringence shows the largest value of0.26@550 nm in chalcogenides,even larger than the commercialized oxide *** Barder charge analysis result indicates that the exceptional birefringence effect is mainly from the Pb2+and S2-in the[Pb S_n]***,the parallelly arranged polyhedral layers could improve the structural ***,this work supports a new method for designing chalcogenides with exceptional birefringence effect in the infrared region.

关键词： Birefringent crystals Chalcogenides Optical properties Structural anisotropic β-Pb3P2S8

结合PLC技术与参数特征提取的地面采油螺杆泵液压故障诊断研究

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液压气动与密封 2025年第2期45卷 118-123页

作者：韩国强中国石油塔里木油田分公司新疆库尔勒841000

为了实现采油螺杆故障诊断的常态化,提升作业设备的可靠性和安全性,首先基于可编程逻辑控制器(PLC)搭建了螺杆泵故障诊断系统架构,然后采用小波包变换以及Fisher判别分析设计了采油螺杆泵液压故障诊断模型。实验结果表明,基于Fisher判... 详细信息

为了实现采油螺杆故障诊断的常态化,提升作业设备的可靠性和安全性,首先基于可编程逻辑控制器(PLC)搭建了螺杆泵故障诊断系统架构,然后采用小波包变换以及Fisher判别分析设计了采油螺杆泵液压故障诊断模型。实验结果表明,基于Fisher判别分析的故障诊断模型在诊断误差上取值0.263,最大R-square取值为0.972。该方法对螺杆泵的故障误报率为0.064,漏报率为0.103,提高了油田的生产效率和经济效益,推动了螺杆泵采油系统的智能化发展。

关键词：可编程逻辑控制器 / 参数特征 / 螺杆泵 / 故障诊断 / 小波包

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我国生物制造底盘菌种现状、问题及对策

中国科学院院刊 2025年第1期40卷 2-13页

作者：陈国强吴赴清郑爽丁军盛君婷清华大学生命科学学院北京100084 清华大学化学工程系北京100084 清华大学合成与系统生物学中心北京100084

生物制造是新质生产力的重要组成部分,是继信息技术之后新一轮科技革命的制高点和产业变革的新引擎,在新能源、新材料、生物医药、绿色食品、环境保护等领域展现出巨大的应用前景。生物制造以底盘菌种为“芯片”,通过菌种设计构建、细... 详细信息

生物制造是新质生产力的重要组成部分,是继信息技术之后新一轮科技革命的制高点和产业变革的新引擎,在新能源、新材料、生物医药、绿色食品、环境保护等领域展现出巨大的应用前景。生物制造以底盘菌种为“芯片”,通过菌种设计构建、细胞规模化培养、产物分离提取等过程,生产各种生物产品。我国生物制造底盘菌种原始创新不足,无法支撑产业健康发展。文章总结了国内外常见底盘菌种类型和新型底盘菌种开发现状,分析了我国底盘菌种开发面临的主要问题和挑战,并针对新型极端微生物底盘菌种开发,从顶层设计、“十五五”布局、平台建设、政策制度、人才培养、审批机制、司法保护、评价体系等方面提出了推进我国自主知识产权底盘菌种开发的若干建议。

关键词：底盘菌种生物制造合成生物新质生产力极端微生物