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用于中国散裂中子源多功能反射谱仪的高气压多丝正比室探测器的研制

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物理学报 2018年第7期67卷 108-116页

作者：温志文祁辉荣张余炼王海云刘凌王艳凤张建李玉红孙志嘉兰州大学核科学与技术学院兰州730000 核探测与核电子学国家重点实验室北京100049 中国科学院高能物理研究所北京100049 中国科学院大学北京100049

中国散裂中子源需要建设一台多功能反射谱仪中子探测器,满足在10年运行期间内,50%(@2A)以上的探测效率、好于2 mm的二维位置分辨、200 mm×200 mm的灵敏面积、3倍的n/γ分辨能力及良好的二维成像性能.基于此要求,探测器因此采用基于高气... 详细信息

中国散裂中子源需要建设一台多功能反射谱仪中子探测器,满足在10年运行期间内,50%(@2A)以上的探测效率、好于2 mm的二维位置分辨、200 mm×200 mm的灵敏面积、3倍的n/γ分辨能力及良好的二维成像性能.基于此要求,探测器因此采用基于高气压~3He气体的多丝正比室,并以满足反射谱仪的探测效率、位置分辨、长期稳定工作和n/y分辨能力为目标进行探测器的设计.本文经过模拟和实验计算得出:以9 mm厚的铝合金入射窗、铝丝密封的高气压腔体和6 bar^3He+2.5 bar C_3H_8的工作气体的设计,可满足探测器对2 A中子10年运行期间内54%以上的探测效率要求;探测器对中子的位置分辨可达到1.4 mm左右;设计的气体净化系统,拥有2 L/min的气流速度可有效去除探测器内的负电性杂质气体,气体循环净化后可提高探测器约27%的气体增益,保证探测器长期稳定的运行;通过对^(252)Cf中子源的能谱测量和成像测量,得出探测器的n/γ分辨能力在5倍以上和均匀的成像结果.研制的探测器满足反射谱仪需求,并已在中国散裂中子源反射谱仪靶站就位联调.

关键词：多丝正比室探测器效率位置分辨 n/γ分辨

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凡纳滨对虾盐碱水养殖池塘沉积物-水界面氮元素交换通量的研究

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水生生物学报 2024年第7期48卷 1183-1192页

作者：杜彦秋吴文广张子军吴桃冯旭张继红上海海洋大学水产与生命学院上海201306 中国水产科学研究院黄海水产研究所青岛海洋科学与技术试点国家实验室海洋渔业科学与食物产出过程功能实验室青岛266071 鄂尔多斯市农牧技术推广中心鄂尔多斯017000

为探究凡纳滨对虾(Litopenaeus vannamei)盐碱水养殖池塘沉积物-水界面中氮元素的转化规律,于2019年5—7月测定了山东省滨州市3个不同盐度(28、45和55)的池塘上覆水和沉积物间隙水中各种形态氮的含量。利用Fick第一定律估算了池塘沉积物... 详细信息

为探究凡纳滨对虾(Litopenaeus vannamei)盐碱水养殖池塘沉积物-水界面中氮元素的转化规律,于2019年5—7月测定了山东省滨州市3个不同盐度(28、45和55)的池塘上覆水和沉积物间隙水中各种形态氮的含量。利用Fick第一定律估算了池塘沉积物-水界面氮元素交换通量,分析了环境因素与交换通量的相关性。结果表明:(1)总体来讲,DIN、DON、TN由沉积物向水体扩散,即沉积物为DIN、DON和TN的源;NO_(3)^(-)-由水体向沉积物扩散,沉积物为NO_(3)^(-)的汇。在养殖期间,盐度28、45和55组,DIN总交换通量分别为1.69、23.07和19.36 mg/m^(2),DON总交换通量分别为36.60、27.90和19.98 mg/m^(2),TN总交换通量分别为38.09、43.66和32.56 mg/m^(2)。(2)从季节变化来看,DIN、DON、TN在养殖初期(5月)的交换通量显著高于养殖末期(7月);从盐度组来看,在5月,盐度28、45和55组,DIN平均交换通量分别为2.08、6.37和12.47 mg/(m^(2)·d),7月分别为-0.48、0.06和1.47 mg/(m^(2)·d),盐度55组显著大于其他两组(P13.91、5.32和6.79 mg/(m^(2)·d),盐度28组显著大于其他两组(P2、10.94和5 mg/(m^(2)·d),盐度45组显著大于其他两组(P15.9、8.79和19.16 mg/(m^(2)·d),盐度45组显著小于其他两组(P1、9.1和3.28 mg/(m^(2)·d),盐度45组显著大于盐度55组(P2)^(-)-N、NO_(3)^(-)-N、NH_(4)^(+)-N交换通量显著正相关;有机质与NH_(4)^(+)、TN通量显著正相关;温度与NH_(4)^(+)交换通量显著负相关;含水率、孔隙度与NO_(3)^(-)-N、DON交换通量显著正相关。综上所述,沉积物是氮的潜在污染源,此污染潜力在养殖末期显著小于养殖初期;高盐度组有利于释放DIN,中低盐度组有利于释放DON。研究结果将有助于认识盐碱水养殖池塘的氮交换通量,为该种养殖模式的科学管理提供数据支撑。

关键词：盐碱水池塘沉积物-水界面氮凡纳滨对虾

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Cr_(3)C_(2)/WC的添加对Stellite 12熔覆层耐磨耐蚀性的影响

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表面技术 2024年第1期53卷 135-142页

作者：赵菲张亮吴志生温保安太原科技大学材料科学与工程学院太原030024

目的提高Stellite 12熔覆层的耐磨耐蚀性能。方法将Stellite 12合金粉末与碳化物(Cr_(3)C_(2)、WC)混合,采用激光熔覆技术在H13钢板上制备复合熔覆层。通过超景深显微镜和XRD分析其显微组织和物相,通过显微硬度测试、摩擦磨损试验和电... 详细信息

目的提高Stellite 12熔覆层的耐磨耐蚀性能。方法将Stellite 12合金粉末与碳化物(Cr_(3)C_(2)、WC)混合,采用激光熔覆技术在H13钢板上制备复合熔覆层。通过超景深显微镜和XRD分析其显微组织和物相,通过显微硬度测试、摩擦磨损试验和电化学腐蚀试验,分别评价熔覆层的硬度、耐磨性和耐蚀性,并通过超景深显微镜对磨痕形貌进行分析。结果添加碳化物后,熔覆层的微观组织以柱状晶和树枝晶为主,物相主要由γ-Co固溶体和碳化物(M23C6、M7C3)组成;Cr_(3)C_(2)的添加使得熔覆层的硬度降低,由610HV0.2降至530HV0.2,但耐磨性得到提高,磨损量由0.45 mm^(3)降至0.33 mm^(3),下降了28%,耐蚀性得到提高,腐蚀电位由-0.385 V增加到-0.264 V,腐蚀电流密度由9.269×10^(-10)A/cm^(2)降至1.496×10^(-10)A/cm^(2),极化电阻由3.982×10^(7)Ω·cm^(2)提升至2.424×10^(8)Ω·cm^(2),提高了1个数量级;WC的添加使其硬度由610HV0.2提高至750HV0.2,磨损深度变浅,磨损量由0.45 mm3降至0.19 mm^(3),下降了43%,但耐腐蚀性有所降低。3种熔覆层的磨损机制主要为磨粒磨损和黏着磨损。结论WC的添加可以有效提高熔覆层的硬度和耐磨性,但耐腐蚀性有所降低;添加Cr_(3)C_(2)后,耐蚀性得到显著提高,耐磨性略微提升,但硬度降低。

关键词：激光熔覆复合熔覆层显微硬度摩擦磨损行为磨损机制电化学腐蚀行为

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Dynamic 3D shape reconstruction under complex reflection and transmission conditions using multi-scale parallel single-pixel imaging

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Light(Advanced Manufacturing) 2024年第3期5卷 93-104页

作者： Zhoujie wu Haoran Wang Feifei Chen Xunren Li Zhengdong Chen Qican zhang School of Electronics and Information Engineering Sichuan UniversityChengduSichuan Province 610065China

Depth measurement and three-dimensional(3D)imaging under complex reflection and transmission conditions are challenging and even impossible for traditional structured light techniques,owing to the precondition of point-to-point *** recent progress in addressing this problem,there is still no efficient and general ***,a Fourier dual-slice projection with depth-constrained localization is presented to separate and utilize different illumination and reflection components efficiently,which can significantly decrease the number of projection patterns in each sequence from thousands to ***,multi-scale parallel single-pixel imaging(MS-PSI)is proposed based on the established and proven position-invariant theorem,which breaks the local regional assumption and enables dynamic 3D *** methodology successfully unveils unseen-before capabilities such as(1)accurate depth measurement under interreflection and subsurface scattering conditions,(2)dynamic measurement of the time-varying high-dynamic-range scene and through thin volumetric scattering media at a rate of 333 frames per second;(3)two-layer 3D imaging of the semitransparent surface and the object hidden behind *** experimental results confirm that the proposed method paves the way for dynamic 3D reconstruction under complex optical field reflection and transmission conditions,benefiting imaging and sensing applications in advanced manufacturing,autonomous driving,and biomedical imaging.

关键词： Computational imaging 3D shape reconstruction 3D imaging Single-pixel imaging Light transport coefficient

Polaron interfacial entropy as a route to high thermoelectric performance in DAE-doped PEDOT:PSS films

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National science Review 2024年第3期11卷 259-270页

作者： Jiajia zhang Caichao Ye Genwang Wei Liang Guo Yuhang Cai Zhi Li Xinzhi wu Fangyi Sun Qikai Li Yupeng Wang Huan Li Yuchen Li Shuaihua Wang Wei Xu Xuefeng Guo wenqing zhang Weishu Liu Department of Materials science and Engineering Southern University of Science and Technology Academy for Advanced Interdisciplinary Studies and Guangdong Provincial Key laboratory of Computational science and Material Design Southern University of Science and Technology Department of Mechanical and Energy Engineering Southern University of Science and Technology beijing National laboratory for Molecular sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences College of Chemistry and Molecular Engineering National Biomedical Imaging Centre Peking University Guangdong Provincial Key laboratory of Functional Oxide Materials and Devices Southern University of Science and Technology

Enhancing the thermoelectric transport properties of conductive polymer materials has been a long-term challenge, in spite of the success seen with molecular doping strategies. However, the strong coupling between the thermopower and the electrical conductivity limits thermoelectric performance. Here, we use polaron interfacial occupied entropy engineering to break through this intercoupling for a PEDOT:PSS(poly（3,4-ethylenedioxythiophene）-poly（4-styrenesulfonate）) thin film by using photochromic diarylethene（DAE） dopants coupled with UV-light modulation. With a 10-fold enhancement of the thermopower from 13.5 μV K-1to 135.4 μV K-1and almost unchanged electrical conductivity, the DAE-doped PEDOT:PSS thin film achieved an extremely high power factor of 521.28 μW m-1K-2from an original value of 6.78 μW m-1K-2. The thermopower was positively correlated with the UV-light intensity but decreased with increasing temperature, indicating resonant coupling between the planar closed DAE molecule and PEDOT. Both the experiments and theoretical calculations consistently confirmed the formation of an interface state due to this resonant coupling. Interfacial entropy engineering of polarons could play a critical role in enhancing the thermoelectric performance of the organic film.

关键词： thermoelectric PEDOT: PSS interfacial occupied entropy resonant coupling UV-light modulation

MRI-guided photothermal/photodynamic immune activation combined with PD-1 inhibitor for the multimodal combination therapy of melanoma and metastases

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Regenerative Biomaterials 2024年第4期3卷 38-51页

作者： Changqiang wu Wei Chen Shuang Yan Jie Zhong Liang Du Chenwu Yang Yu Pu Yang Li Jiafu Lin Mei Zeng Xiaoming zhang Medical imaging Key laboratory of Sichuan Province and School of Medical imaging North Sichuan Medical CollegeNanchong 637000P.R.China Department of Radiology Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000P.R.China Antibiotics Research and Re-evaluation Key laboratory of Sichuan Province Sichuan Industrial Institute of AntibioticsSchool of PharmacyChengdu UniversityChengdu 610106P.R.China Institute of Basic Medicine and Forensic Medicine North Sichuan Medical College and Institute of Rheumatology and ImmunologyThe Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000P.R.China

Non-invasive image-guided precise photothermal/photodynamic therapy(PTT/PDT)has been proven to be an effective local treatment modality but incompetent against ***,the combination of local PTT/PDT and systemic immunotherapy would be a promising strategy for tumor ***,a magnetic resonance imaging(MRI)-visualized PTT/PDT agent(SIDP NMs)was constructed,and the efficacy of its multimodal combination with a programmed cell death 1(PD-1)inhibitor in the treatment of melanoma and metastases was *** to the hydrophobic encapsulation of indocyanine green within the micellar core,SIDP NMs exhibited excellent photothermal/photodynamic properties and stability under an 808 nm near-infrared *** vitro cell experiments showed that SIDP NMs had a good killing *** incubating with B16-F10 cells for 24 h and irradiating with an 808-nm laser for 10 min,cell viability decreased *** resonance imaging experiments in melanoma-bearing mice have shown that the dynamic distribution of SIDP NMs in tumor tissue could be monitored by T2WI and T2-MAP non-invasively due to the presence of superparamagnetic iron oxide nanocrystal in SIDP *** the 808 nm laser was irradiated at the maximum focusing time point shown by MRI,the temperature of the tumor area rapidly increased from 32℃to 60.7℃in 5 *** mouse melanoma ablation and distant tumor immunotherapy studies,SIDP NMs provided excellent MRI-guided PTT/PDT results and,when combined with PD-1 inhibitor,have great potential to cure primary tumors and eradicate metastases.

关键词： photothermal therapy photodynamic therapy immunotherapy magnetic resonance imaging multimodal treatment

Design of new intelligent street light control system

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Design of new intelligent street light control system

2009年中国智能自动化会议

作者： wu Yue~(1,2),SHI Changhong~3,LI Yan~1,zhang wen-dong~1 (1 National Key laboratory for Electronic Measurement technology, North University of china,Taiyuan 030051,china 2 The Mechanical and Electronic Engineering College, North University of china,Taiyuan 030051,china 3 The Quartermaster Institute of the General Logistics Department of the P.L.A, beijing 100010,china)

In china,the methods of time-control,optical-control and time-optical-control are in common used to control street lamp,particularly in small and medium-sized cities. But the precision is bad,and the result of work is also *** main reason is the backward lighting control and administrative method. Through many kinds of sensor combination sense environment’s change,the multi-sensor exhibition can combinatory logically control the new intelligent street light controller *** based on the degree of illumination control fixed time,in the automatic foundation fixed time,according to the multi-sensing exhibition survey data’s special combination change,to control the street light nimbly;the system can also realize the automatic timing control,by the preinstall time to control street light switch,ultimately, to control the street light timed;Simultaneously can also realize the automatic sunshine control,which may act according to the actual determination the sunlight degree of illumination and the degree of illumination control criterion,automatic control street light. On the basis of the merits both the regular control and the optical control,a new street smart controller is designed,with dual functions both timing control and automatic photoelectric *** allows street lamps automatic lit in the evening,lighting the road for a few hours(adjustable time).After 0:00,when few vehicles or pedestrians go past,it turn off *** terminal controller has wake-up *** the street light turn out automatically,when the vehicles or pedestrians are going through,street light will be waken up by terminal controller,When the vehicles or pedestrians past,the light *** of new intelligent street light control system does not only achieve energy-saving power but also extend the service life of lighting ***,it is controllable,ease of *** the same time,it is helpful to highlight the festive and other characteristics,an

关键词： Public street lighting intelligent controller

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大预准直狭缝的铬原子束一维多普勒激光准直

物理学报 2008年第9期57卷 5485-5490页

作者：张宝武张文涛马艳李同保同济大学物理系上海200092

介绍了横向尺寸为5 mm的大尺寸预准直狭缝前提下,铬原子束的一维多普勒激光准直实验,研究了激光功率和作用区域对铬原子束激光准直效果的影响.从激光驻波场中原子所受的力出发,利用适当步长的四阶Runge-Kutta算法对实验进行理论模拟.理... 详细信息

介绍了横向尺寸为5 mm的大尺寸预准直狭缝前提下,铬原子束的一维多普勒激光准直实验,研究了激光功率和作用区域对铬原子束激光准直效果的影响.从激光驻波场中原子所受的力出发,利用适当步长的四阶Runge-Kutta算法对实验进行理论模拟.理论结果和通过Matlab程序读取的实验结果都表明在这种大尺寸的预准直狭缝前提下,经激光准直后的原子束的横向分布被压缩的同时,峰值也被大大提高.在作用区域一定时,随着激光功率的增加准直原子束的半高宽有减小的趋势,峰值有增大的趋势;激光功率一定时,随着作用区域的增加激光功率的增加准直原子束的半高宽有减小的趋势,峰值有增大的趋势.

关键词：铬原子束光学粘胶激光准直激光稳频

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非均相催化一步合成碳酸二苯酯的研究 Ⅷ.Ce和Sn的添加量对Pd/La_(0.62)Pb_(0.38)MnO_3催化剂性能的影响

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天然气化工—C1化学与化工 2004年第4期29卷 33-37页

作者：张光旭吴元欣马沛生吴广文李定或武汉化工学院新型反应器与绿色化学工艺湖北省重点实验室武汉430074 天津大学化工学院天津300072

通过XRD对不同的Ce和Sn添加量所得催化剂的物相进行了表征,结果表明当Sn的负载量大于14 3%,Ce的添加量大于5%时,所得催化剂中主要物相仍为La0 62Pb0 38MnO3,同时也有物相CeXSn1-xO2少量存在,且其随Ce的负载量的增大而减少,x值也降低,此... 详细信息

通过XRD对不同的Ce和Sn添加量所得催化剂的物相进行了表征,结果表明当Sn的负载量大于14 3%,Ce的添加量大于5%时,所得催化剂中主要物相仍为La0 62Pb0 38MnO3,同时也有物相CeXSn1-xO2少量存在,且其随Ce的负载量的增大而减少,x值也降低,此外存在其他杂相。由SEM、TEM及ChemBET3000比表面仪测试结果可知,当Ce的添加量为5%,Sn的负载量为14 3%时,催化剂的比表面积、空隙率较大,粒度分布较好。用DPC的合成实验对不同催化剂的活性及催化剂的寿命进行评价,结果表明无论是催化剂的活性还是催化剂的寿命当Ce的添加量为5%,Sn的负载量为14 3%时所得的催化剂的活性和寿命都较好。

关键词：碳酸二苯酯 Pd负载催化剂 Ce添加量

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