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SAR regional all-azimuth observation orbit design for target 3D reconstruction
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作者 WANG Yanan ZHOU Chaowei +1 位作者 LIU Aifang MAO Qin 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期609-618,共10页
Three-dimensional(3D) synthetic aperture radar(SAR)extends the conventional 2D images into 3D features by several acquisitions in different aspects. Compared with 3D techniques via multiple observations in elevation, ... Three-dimensional(3D) synthetic aperture radar(SAR)extends the conventional 2D images into 3D features by several acquisitions in different aspects. Compared with 3D techniques via multiple observations in elevation, e.g. SAR interferometry(InSAR) and SAR tomography(TomoSAR), holographic SAR can retrieve 3D structure by observations in azimuth. This paper focuses on designing a novel type of orbit to achieve SAR regional all-azimuth observation(AAO) for embedded targets detection and holographic 3D reconstruction. The ground tracks of the AAO orbit separate the earth surface into grids. Target in these grids can be accessed with an azimuth angle span of360°, which is similar to the flight path of airborne circular SAR(CSAR). Inspired from the successive coverage orbits of optical sensors, several optimizations are made in the proposed method to ensure favorable grazing angles, the performance of 3D reconstruction, and long-term supervision for SAR sensors. Simulation experiments show the regional AAO can be completed within five hours. In addition, a second AAO of the same area can be duplicated in two days. Finally, an airborne SAR data process result is presented to illustrate the significance of AAO in 3D reconstruction. 展开更多
关键词 synthetic aperture radar(SAR) orbit design all-azimuth observation(AAO) three-dimensional(3D)reconstruction successive coverage
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(1-3)-β-D葡聚糖联合降钙素原、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究
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作者 黄强 王宇 +5 位作者 江渊 梁道斌 黄锐洁 秦小超 潘燕妮 和鹰 《中国真菌学杂志》 CSCD 2024年第1期21-24,29,共5页
目的探讨(1-3)-β-D葡聚糖联合降钙素原(procalcitonin,PCT)、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究。方法回顾性选取我院2020年1月—2022年6月住院的120例艾滋病患者为研究对象。依据实验室结果,将... 目的探讨(1-3)-β-D葡聚糖联合降钙素原(procalcitonin,PCT)、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究。方法回顾性选取我院2020年1月—2022年6月住院的120例艾滋病患者为研究对象。依据实验室结果,将其分为马尔尼菲篮状菌感染确诊组(血或组织液培育养出马尔尼菲篮状菌),简称A组(62例),及马尔尼菲篮状菌感染临床诊断组[根据临床症状、体征、血常规及(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞多指标诊断],简称B组(58例)。检测患者(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞的表达水平,采用受试者工作特征(receiver-operating characteristic,ROC)曲线下面积(area under the curve,AUC)评估上述指标联合检测对艾滋病患者感染马尔尼菲篮状菌的诊断效能。结果A组的(1-3)-β-D葡聚糖和PCT水平均高于B组,CD4^(+)T淋巴细胞个数低于B组(P<0.05);(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞联合检测的AUC为0.933,(1-3)-β-D葡聚糖单独检测的AUC是0.812,PCT单独检测的AUC为0.883,CD4^(+)T淋巴细胞单独检测的AUC是0.810,(1-3)-β-D葡聚糖、PCT和CD4^(+)T淋巴细胞联合检测的AUC皆优于三项单独检测,表明(1-3)-β-D葡聚糖、PCT和CD4^(+)T淋巴细胞联合检测的诊断价值皆优于单一指标诊断,且联合检测的特异度、约登指数分别为92.43%和0.580,均高于三项单独检测。结论(1-3)-β-D葡聚糖联合PCT和CD4^(+)T淋巴细胞多指标对艾滋病马尔尼菲篮状菌感染具有非常高的临床诊断价值,能够帮助医生分析出高危风险患者,及时制定治疗方案,同时也承担预后效果的判断依据,对治疗艾滋病马尔尼菲篮状菌感染具有非常重要的研究价值。 展开更多
关键词 (1-3)-β-d葡聚糖 PCT CD4^(+)T淋巴细胞 艾滋病 马尔尼菲篮状菌感染
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1例RHD-CE(3-7)-D基因重组与RHCE变异型患者的血清学与分子生物学分析
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作者 唐炳娣 蔡仲仁 +1 位作者 邓泳诗 伍昌林 《分子诊断与治疗杂志》 2024年第6期1183-1186,1190,共5页
目的 研究分析1例Rh血型弱D、弱cE患者的血清学与分子生物学特征,为该类患者的临床安全输血提供实验依据。方法 采用微柱凝胶卡法对患者红细胞进行ABO、RhDCcEe抗原的鉴定,同时采用试管法进行血型复核,抗人球蛋白卡法筛查不规则抗体;采... 目的 研究分析1例Rh血型弱D、弱cE患者的血清学与分子生物学特征,为该类患者的临床安全输血提供实验依据。方法 采用微柱凝胶卡法对患者红细胞进行ABO、RhDCcEe抗原的鉴定,同时采用试管法进行血型复核,抗人球蛋白卡法筛查不规则抗体;采用PCR-SSP法对RhDCcEe(RhD、RhC、Rhc、RhE、Rhe)基因型进行检测;三代全长测序技术对RHD/RHCE基因序列进行测序分析。结果 微柱凝胶卡法鉴定ABO、RhD、RhCcEe血型抗原的结果为:A抗原(-)、B抗原(-)、RhD(1+)、RhC(4+)、Rhc(1+)、RhE(1+)、Rhe(4+)、对照孔(-);试管法ABO、RhD、RhCcEe抗原鉴定该患者表型为:A抗原(-)、B抗原(-)、RhD(w+)、RhC(4+)、Rhc(w+)、RhE(w+)、Rhe(4+),对照管(-);抗人球蛋白卡法筛查患者不规则抗体阴性;PCR-SSP法血型基因分型RhDCcEe结果:RhD(+)、RhC(+)、Rhc(+)、RhE(+)、Rhe(+);RHD/RHCE基因结果:RHD单倍体1为外显子1-10全缺失,而单倍体2为外显子RHD-CE基因重组融合,且确认其重组类型为RHD-CE(3-7)-D,起点在外显子2(g.20238-20312之间),终点在外显子8(g49184-50480之间),同时RHCE基因第6外显子存在新碱基点突变RHCE*cE(827C>A)。结论RHD-CE(3-7)-D基因重组融合与RHCE*cE(827C>A)新等位基因突变可能引起D、cE血型抗原弱表达,为临床安全输血提供了重要的实验数据支持。 展开更多
关键词 RhD/cE弱抗原 RHD-CE(3-7)-d重组 RHCE*cE(827C>A) 三代全长测序
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The First Global Map of Atmospheric Ammonia(NH_(3)) as Observed by the HIRAS/FY-3D Satellite
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作者 Minqiang ZHOU Zhili DENG +6 位作者 Charles ROBERT Xingying ZHANG Lu ZHANG Yapeng WANG Chengli QI Pucai WANG Martine De MAZIÈRE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期379-390,共12页
Atmospheric ammonia(NH_(3)) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH_(3) concentra... Atmospheric ammonia(NH_(3)) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH_(3) concentration based on the absorption lines of NH_(3) in the thermal infrared region. In this study, we establish a retrieval algorithm to derive the NH_(3)column from the Hyperspectral Infrared Atmospheric Sounder(HIRAS) onboard the Chinese Feng Yun(FY)-3D satellite and present the first atmospheric NH_(3) column global map observed by the HIRAS instrument. The HIRAS observations can well capture NH_(3) hotspots around the world, e.g., India, West Africa, and East China, where large NH_(3) emissions exist. The HIRAS NH_(3) columns are also compared to the space-based Infrared Atmospheric Sounding Interferometer(IASI)measurements, and we find that the two instruments observe a consistent NH_(3) global distribution, with correlation coefficient(R) values of 0.28–0.73. Finally, some remaining issues about the HIRAS NH_(3) retrieval are discussed. 展开更多
关键词 AMMONIA HIRAS/FY-3D satellite thermal-infrared observation remote sensing optimal estimation method
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基于二萘并[2,3-B∶2′,3′-D]呋喃基团的高效窄发射蓝光OLED器件
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作者 王小伟 袁江波 +4 位作者 马佩兰 闫自强 崔志远 孙军 彭其明 《发光学报》 EI CAS CSCD 北大核心 2024年第9期1503-1510,共8页
高效率窄光谱蓝色有机电致发光器件(OLED)是柔性显示领域的研究重点之一。本文以二萘并[2,3-B∶2′,3′-D]呋喃为弱电子受体、N-(4-联苯基)-1-萘胺作为电子给体设计合成了一种D-A-D型蓝光分子DPF-NA,其在正己烷溶液中的发射峰位于441 n... 高效率窄光谱蓝色有机电致发光器件(OLED)是柔性显示领域的研究重点之一。本文以二萘并[2,3-B∶2′,3′-D]呋喃为弱电子受体、N-(4-联苯基)-1-萘胺作为电子给体设计合成了一种D-A-D型蓝光分子DPF-NA,其在正己烷溶液中的发射峰位于441 nm。理论计算与光物理测试结果显示DPF-NA具有杂化局域电荷转移激发态(HLCT)特性,兼具局域态(LE)高发光效率与电荷转移态(CT)高激子利用率特征,在二氯甲烷溶液中的光致发光量子效率(PLQY)为81.2%。基于质量分数3%DPF-NA掺杂浓度的OLED器件电致发光(EL)峰位于455 nm,半峰宽(FWHM)仅为26 nm,CIE(x,y)坐标为(0.14,0.08),最大外量子效率(EQEmax)为6.76%。 展开更多
关键词 有机电致发光器件 二萘并[2 3-B∶2′ 3-d]呋喃 蓝光 激子利用 外量子效率
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New 4-imino-4H-Chromeno[2,3-d]Pyrimidin-3(5H)-Amine: Synthesis, Cytotoxic Effects on Tumoral Cell Lines and in Silico ADMET Properties
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作者 Marwa Dhiabi Sirine Karoui +7 位作者 Mehdi Fakhfakh Souhir Abid Emmanuelle Limanton Rémy Le Guével Thierry Charlier Ludovic Paquin Jean-Pierre Bazureau Houcine Ammar 《International Journal of Organic Chemistry》 2024年第3期107-122,共16页
The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was establishe... The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was established according to their spectroscopic analysis, such as FT-IR, NMR and mass spectroscopy. These new compounds were tested for their antiproliferative activities on seven representative human tumoral cell lines (Huh7 D12, Caco2, MDA-MB231, MDA-MB468, HCT116, PC3 and MCF7) and also on fibroblasts. Among them, only the compounds 6c showed micromolar cytotoxic activity on tumor cell lines (1.8 50 50 > 25 μM). Finally, in silico ADMET studies ware performed to investigate the possibility of using of the identified compound 6c as potential anti-tumor compound. 展开更多
关键词 2-Amino-4H-Chromene 4H-Chromeno[2 3-d]Pyrimidin-3(5H)-Amine Microwave Irradiation Tumoral Cell Line in Silico ADMET
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血浆(1-3)-β-D葡聚糖诊断新生儿侵袭性真菌感染的价值
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作者 邵碧波 刘思佳 李益廷 《中文科技期刊数据库(文摘版)医药卫生》 2024年第3期0001-0004,共4页
探讨在针对新生儿侵袭性真菌感染的诊断中使用血浆(1-3)-β-D葡聚糖能够产生的诊断效能。方法 选取2021年1月到2022年2月因为侵袭性真菌感染于医院寻求医疗干预的新生儿总共60例作为本次研究的一部分研究对象记为1组;另外选取60例健康... 探讨在针对新生儿侵袭性真菌感染的诊断中使用血浆(1-3)-β-D葡聚糖能够产生的诊断效能。方法 选取2021年1月到2022年2月因为侵袭性真菌感染于医院寻求医疗干预的新生儿总共60例作为本次研究的一部分研究对象记为1组;另外选取60例健康婴儿作为2组;统计、对比两组患者的血浆(1-3)-β-D葡聚糖水平、CD4+T淋巴细胞数水平;整理PCR技术针对1组患者诊断结果,将其与血浆(1-3)-β-D葡聚糖诊断侵袭性真菌感染的诊断效能进行对比。结果 研究结果显示1组患者的血浆(1-3)-β-D葡聚糖水平、CD4+T淋巴细胞数水平较之于2组患者存在明显差异,1组患者血浆(1-3)-β-D葡聚糖水平更高,而CD4+T淋巴细胞数水平明显更低;P<0.05。在针对诊断效能的考察上,血浆(1-3)-β-D葡聚糖诊断效能和PCR诊断结果之间在灵敏度、特异度方面差异不大,P>0.05。结论 针对罹患侵袭性真菌感染的新生儿使用血浆(1-3)-β-D葡聚糖进行检查,一定程度上能够确保诊断结果的严谨程度,可使用。 展开更多
关键词 侵袭性真菌感染 诊断 血浆(1-3)-β-d葡聚糖
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血浆(1,3)-β-D葡聚糖检测在侵袭性真菌感染诊断中的价值分析
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作者 王珍珍 《中国科技期刊数据库 医药》 2024年第9期0150-0153,共4页
研究血浆(1,3)-β-D葡聚糖检测技术(G实验)应用于侵袭性真菌感染(IFI)诊断中的应用价值。方法 选择我院在2023年1月至2024年1月期间收治的100例高危型侵袭型真菌感染患者,应用MB-80微生物快速检测动态系统以及对应的试剂对患者的血浆(1,... 研究血浆(1,3)-β-D葡聚糖检测技术(G实验)应用于侵袭性真菌感染(IFI)诊断中的应用价值。方法 选择我院在2023年1月至2024年1月期间收治的100例高危型侵袭型真菌感染患者,应用MB-80微生物快速检测动态系统以及对应的试剂对患者的血浆(1,3)-β-D葡聚糖进行检测,分析真菌培养、G实验和联合检测结果;三种方法的诊断效能;三种方法的ROC曲线。结果 确诊IFI阳性共28例,阴性共72例;联合检测的诊断效能高于真菌培养或者G实验。联合检测面积高于单一检测。结论 在侵袭性真菌感染的诊断中,应用血浆(1,3)-β-D葡聚糖检测,诊断效能良好,在和传统真菌培养技术联合检测下,可进一步提升诊断效能。 展开更多
关键词 血浆(1 3)-β-d葡聚糖检测技术 侵袭性真菌感染 诊断效能
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泰山夏季O_(3)和PM_(2.5)污染特征及成因分析 被引量:1
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作者 乜艳秋 朱玉姣 +10 位作者 张吉 赵勇 国兆新 刘玉虹 李洪勇 吴迪 高健 李红 王新锋 薛丽坤 王文兴 《环境科学研究》 CAS CSCD 北大核心 2024年第3期427-438,共12页
华北地区是我国空气污染最严重的地区之一.泰山为华北平原最高峰,可代表华北地区背景大气的环境特征.本研究利用2021年6−8月在泰山顶的强化观测数据,开展了基于观测的化学盒子模型模拟,结合位于泰山下国控站点(泰安市监测站)同期监测数... 华北地区是我国空气污染最严重的地区之一.泰山为华北平原最高峰,可代表华北地区背景大气的环境特征.本研究利用2021年6−8月在泰山顶的强化观测数据,开展了基于观测的化学盒子模型模拟,结合位于泰山下国控站点(泰安市监测站)同期监测数据的对比分析,探究了泰山顶夏季PM_(2.5)和O_(3)的污染特征及成因机制.结果表明:①观测期间,泰山顶NO2、SO2、CO的日均浓度均明显低于泰山下,而泰山顶O_(3)浓度相对更高.泰山顶O_(3)浓度超标天数为61 d,超标率为67.0%,最长连续超标天数达23 d;泰山顶PM_(2.5)日均浓度亦略高于泰山下.②泰山顶日间(07:00−17:00)O_(3)浓度主要来源于光化学反应,而夜间主要来源于区域传输.观测期间,泰山顶O_(3)的生成主要处于NO_(x)控制区.③随PM_(2.5)小时平均浓度的增加,其中二次无机盐(硫酸盐、硝酸盐和铵盐)浓度增加的比例大于有机物;与清洁时段(PM_(2.5)小时浓度小于35μg/m^(3)的时段)相比,PM_(2.5)污染时段(PM_(2.5)小时浓度大于35μg/m^(3)的时段)二次无机盐浓度占比增加了13.1%.④泰山顶PM_(2.5)日均浓度和O_(3)日最大8 h平均浓度(MDA8 O_(3)浓度)呈显著正相关(R=0.73,P<0.01).观测期间共发生50次PM_(2.5)和O_(3)小时浓度同步升高的现象,O_(3)浓度平均升速为(10.1±5.3)μg/(m^(3)·h),PM_(2.5)浓度平均升速为(9.5±6.4)μg/(m^(3)·h),二者同步升高的持续时间为2~14 h.PM_(2.5)和O_(3)小时浓度同步升高的过程倾向于发生在静风时段,与地面污染物向山顶输送、光化学反应、液相反应及残留层中的传输过程有关.研究显示,泰山O_(3)和PM_(2.5)污染防控需关注周边地区污染物排放及残留层传输的影响. 展开更多
关键词 泰山 PM_(2.5) O_(3) VOCS 基于观测的模型(OBM)
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Parallel computing approach for efficient 3-D X-ray-simulated image reconstruction 被引量:1
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作者 Ou-Yi Li Yang Wang +1 位作者 Qiong Zhang Yong-Hui Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第7期122-136,共15页
Accurate 3-dimensional(3-D)reconstruction technology for nondestructive testing based on digital radiography(DR)is of great importance for alleviating the drawbacks of the existing computed tomography(CT)-based method... Accurate 3-dimensional(3-D)reconstruction technology for nondestructive testing based on digital radiography(DR)is of great importance for alleviating the drawbacks of the existing computed tomography(CT)-based method.The commonly used Monte Carlo simulation method ensures well-performing imaging results for DR.However,for 3-D reconstruction,it is limited by its high time consumption.To solve this problem,this study proposes a parallel computing method to accelerate Monte Carlo simulation for projection images with a parallel interface and a specific DR application.The images are utilized for 3-D reconstruction of the test model.We verify the accuracy of parallel computing for DR and evaluate the performance of two parallel computing modes-multithreaded applications(G4-MT)and message-passing interfaces(G4-MPI)-by assessing parallel speedup and efficiency.This study explores the scalability of the hybrid G4-MPI and G4-MT modes.The results show that the two parallel computing modes can significantly reduce the Monte Carlo simulation time because the parallel speedup increment of Monte Carlo simulations can be considered linear growth,and the parallel efficiency is maintained at a high level.The hybrid mode has strong scalability,as the overall run time of the 180 simulations using 320 threads is 15.35 h with 10 billion particles emitted,and the parallel speedup can be up to 151.36.The 3-D reconstruction of the model is achieved based on the filtered back projection(FBP)algorithm using 180 projection images obtained with the hybrid G4-MPI and G4-MT.The quality of the reconstructed sliced images is satisfactory because the images can reflect the internal structure of the test model.This method is applied to a complex model,and the quality of the reconstructed images is evaluated. 展开更多
关键词 Parallel computing Monte Carlo Digital radiography 3-d reconstruction
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血清25-羟维生素-D3 超敏C反应蛋白及心电图参数与ST段抬高型心肌梗死患者介入治疗后发生恶性心律失常的关系 被引量:12
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作者 李永慧 王小玲 +2 位作者 原文龙 王蕾 屈艳玲 《河北医学》 CAS 2023年第2期265-270,共6页
目的:探讨血清25-羟维生素-D3(25-hydroxyvitamin D3,25-(OH)-D3)、超敏C反应蛋白(High sensitivity C-reactive protein,hs-CRP)、心电图参数变化与ST段抬高型心肌梗死(ST segment elevation myocardial infarction,STEMI)患者经皮冠... 目的:探讨血清25-羟维生素-D3(25-hydroxyvitamin D3,25-(OH)-D3)、超敏C反应蛋白(High sensitivity C-reactive protein,hs-CRP)、心电图参数变化与ST段抬高型心肌梗死(ST segment elevation myocardial infarction,STEMI)患者经皮冠脉介入术(Percutaneous coronary intervention,PCI)后发生恶性心律失常的关系。方法:选取我院2020年1月至2022年6月实施PCI治疗的193例STEMI患者作为研究对象,根据患者术后72h内是否发生恶性心律失常分为心律失常组38例、对照组155例,对比两组患者入院12h内的25-(OH)-D3、hs-CRP、血清电解质、血常规指标、血脂指标、心肌酶学指标,并对患者PCI术后实施连续动态心电图监测,对比两组患者心电图碎裂QRS波、校正Tp-e间期(Corrected Tp-e interval,Tp-ec)、QT离散度(QT dispersion,Qtd),并采用Logistic回归模型分析上述指标与STEMI患者PCI术后发生恶性心律失常的关系。结果:心律失常组患者的血清25-(OH)-D3水平低于对照组,心律失常组患者的血清hs-CRP、Tp-ec测定值、Qtd测定值、碎裂QRS波检出率均高于对照组,上述指标组间差异均具有统计学意义(P<0.05);心律失常组患者的白细胞(White blood cell,WBC)、肌钙蛋白I(Troponin I,cTnI)、肌酸激酶同工酶(Creatine kinase isoenzyme,CK-MB)、肌红蛋白(Myoglobin,MYO)、K+、Mg 2+水平均高于对照组患者,差异具有统计学意义(P<0.05);Logistic回归模型结果显示:cTnI、CK-MB、K+、hs-CRP、Tp-ec、Qtd增高,碎裂QRS波阳性会显著增大STEMI患者PCI后发生恶性心律失常的风险(P<0.05);血清25-(OH)-D3水平增高会降低STEMI患者PCI后发生恶性心律失常的风险(P<0.05)。结论:STEMI患者血清25-(OH)-D3水平降低、hs-CRP增高、PCI术后Tp-ec、Qtd增高、出现碎裂QRS波会增大患者出现恶性心律失常的风险。 展开更多
关键词 25-羟维生素-d3 超敏C反应蛋白 动态心电图 ST段抬高型心肌梗死 经皮冠脉介入术 恶性心律失常
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Fe_(3)O_(4)/BiOBr/BiOI的制备及降解2,4-D的性能研究 被引量:2
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作者 刘家豪 张梦朝 +5 位作者 文斯捷 谢剑锋 董丽 杨代琼 党晶晶 卢昶雨 《应用化工》 CAS CSCD 北大核心 2023年第1期47-52,共6页
采用水热法制备了微米球花状结构的Fe_(3)O_(4)/BiOBr/BiOI复合材料,通过SEM、XRD、XPS和UV-Vis等手段对催化剂进行表征分析。结果表明,该催化剂对2,4-D具有高效的光降解性能和光催化效率(80 min,88%)。降解速率常数为2.498×10^(-2... 采用水热法制备了微米球花状结构的Fe_(3)O_(4)/BiOBr/BiOI复合材料,通过SEM、XRD、XPS和UV-Vis等手段对催化剂进行表征分析。结果表明,该催化剂对2,4-D具有高效的光降解性能和光催化效率(80 min,88%)。降解速率常数为2.498×10^(-2)min^(-1),分别是Br∶I=5∶5(K=2.004×10^(-2)min^(-1))、BiOBr(K=1.289×10^(-2)min^(-1))和BiOI(K=6.98×10-3min-1)的1.25倍、1.94倍与3.58倍。这是由于Fe_(3)O_(4)/BiOBr/BiOI复合材料内部形成了异质结,利于光生载流子的分离。此外,5次循环实验后,降解效率保持在82.9%,证明该催化剂稳定、可回收、可磁分离。 展开更多
关键词 Fe_(3)O_(4)/BiOBr/BiOI 光催化 2 4-d 复合材料
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50W800无取向硅钢中Al_(2)O_(3)和Al_(2)O_(3)-MnS夹杂物的腐蚀行为研究 被引量:3
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作者 向继明 周和荣 《热加工工艺》 北大核心 2024年第8期107-112,共6页
采用无取向硅钢退火样进行原位腐蚀实验,对试样表面腐蚀形貌进行OM表征、SEM表征、EDS分析、拉曼光谱表征。结果表明,无取向硅钢的腐蚀源自夹杂物的局部腐蚀,其中包含金属氧化物夹杂Al_(2)O_(3)、金属氧硫化物夹杂Al_(2)O_(3)-MnS。无... 采用无取向硅钢退火样进行原位腐蚀实验,对试样表面腐蚀形貌进行OM表征、SEM表征、EDS分析、拉曼光谱表征。结果表明,无取向硅钢的腐蚀源自夹杂物的局部腐蚀,其中包含金属氧化物夹杂Al_(2)O_(3)、金属氧硫化物夹杂Al_(2)O_(3)-MnS。无取向硅钢初期腐蚀时圆形锈斑内腐蚀产物主要为γ-FeOOH和α-Fe_(2)O_(3),且γ-FeOOH含量高于α-Fe_(2)O_(3)。随着腐蚀产物的颜色加深,α-Fe_(2)O_(3)含量逐渐增多。 展开更多
关键词 无取向硅钢 夹杂物 Al_(2)O_(3) Al_(2)O_(3)-MnS 原位观察
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南京地区局地积累型和外来输送型O_(3)污染模拟研究
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作者 裴宇儇 彭薇 +5 位作者 王红磊 卢文 赵天良 刘思晗 武自豪 可玥 《地球与环境》 CAS CSCD 北大核心 2024年第2期154-165,共12页
利用观测资料和WRF-Chem空气质量模式对南京地区局地积累型和外来输送型O_(3)污染过程的时空分布特征和潜在机制进行了研究。结果表明:(1)水平分布特征,在两次O_(3)污染整体过程中,外来输送型O_(3)污染浓度高值区分布范围相比局地积累... 利用观测资料和WRF-Chem空气质量模式对南京地区局地积累型和外来输送型O_(3)污染过程的时空分布特征和潜在机制进行了研究。结果表明:(1)水平分布特征,在两次O_(3)污染整体过程中,外来输送型O_(3)污染浓度高值区分布范围相比局地积累型更大且较为分散。但在两次O_(3)污染过程中最严重的白天,局地积累型O_(3)污染浓度高值区分布范围大且集中,O_(3)浓度大部分均超过160μg/m^(3);而外来输送型O_(3)污染浓度高值区分布范围更小且更为分散,O_(3)浓度在120~160μg/m^(3)的地区范围显著大于局地积累型O_(3)污染;(2)垂直分布特征,在污染过程前期,局地积累型O_(3)污染在2 km以下高度处有着高浓度O_(3),浓度最高超250μg/m^(3),而外来输送型O_(3)污染浓度高值区主要集中在2~2.5 km高度处,且高值区浓度最高不超过200μg/m^(3);在污染过程中期,局地积累型O_(3)污染浓度高值区集中在2 km高度下,且在1 km左右高度处O_(3)浓度出现最大值;而外来输送型O_(3)污染浓度高值区最高可达到2.6 km左右,并且浓度最大值集中在1.5 km高度以下,均超过250μg/m^(3);在污染过程后期,局地积累型O_(3)污染浓度高值区逐渐消散,但外来输送型O_(3)污染在0.5~3 km高度内仍出现大范围O_(3)浓度高值区;(3)在生成机理方面,近地面O_(3)的高浓度在局地积累型O_(3)污染中主要依赖于垂直混合,96h内总贡献为451.7μg/m^(3),在总过程量中占比为66.2%,而在外来输送型O_(3)污染中主要依赖于水平平流和垂直混合,72h内总贡献分别为1050.2μg/m^(3)和799.1μg/m^(3),总量在总过程量中占比为61.5%。在500 m高度处,局地积累型O_(3)污染前期O_(3)的高浓度主要依赖于垂直平流和化学过程,中期只依赖于化学过程,后期则主要依赖于水平平流和化学过程。但在外来输送型O_(3)污染前中后期中高O_(3)浓度均主要依赖于水平平流和化学过程。在1000 m高度处,两个过程中O_(3)浓度的正贡献均主要受化学过程控制。 展开更多
关键词 O_(3) 观测分析 WRF-Chem 过程分析 南京
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Building 3-D Human Data Based on Handed Measurement and CNN
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作者 Bich Nguyen Binh Nguyen +3 位作者 Hai Tran Vuong Pham Le Nhi Lam Thuy Pham The Bao 《Computers, Materials & Continua》 SCIE EI 2023年第2期2431-2441,共11页
3-dimension(3-D)printing technology is growing strongly with many applications,one of which is the garment industry.The application of human body models to the garment industry is necessary to respond to the increasin... 3-dimension(3-D)printing technology is growing strongly with many applications,one of which is the garment industry.The application of human body models to the garment industry is necessary to respond to the increasing personalization demand and still guarantee aesthetics.This paper proposes amethod to construct 3-D human models by applying deep learning.We calculate the location of the main slices of the human body,including the neck,chest,belly,buttocks,and the rings of the extremities,using pre-existing information.Then,on the positioning frame,we find the key points(fixed and unaltered)of these key slices and update these points tomatch the current parameters.To add points to a star slice,we use a deep learning model tomimic the form of the human body at that slice position.We use interpolation to produce sub-slices of different body sections based on the main slices to create complete body parts morphologically.We combine all slices to construct a full 3-D representation of the human body. 展开更多
关键词 3-d human model deep learning INTERPOLATION
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The first quantitative joint observation of typhoon by Chinese GF-3 SAR and HY-2A microwave scatterometer 被引量:7
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作者 LIN Mingsen YE Xiaomin YUAN Xinzhe 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第11期1-3,共3页
The typhoon, as a mature tropical cyclone that develops in the western part of the North Pacific Ocean with high wind speed and heavy rainfall, is one of the most lethal and costly of natural disasters for the densely... The typhoon, as a mature tropical cyclone that develops in the western part of the North Pacific Ocean with high wind speed and heavy rainfall, is one of the most lethal and costly of natural disasters for the densely populated countries of East Asia. It can be easily detected by space-borne sensors operated at microwave, visible or infrared bands (Liu et al., 2014). Synthetic Aperture Radar (SAR) is a kind of active imaging radar, which can detect the targets with high resolution at one-meter level. SARs can be used to extract the sea surface wind and the eyes of typhoons or hurricanes (Friedman and Li, 2000; Zhang and Perrie, 2012; Li, 2015; Jin et al., 2014; Liu et al., 2014). As a pioneer project of Haiyang-3 (HY-3), the Chinese C-band SAR satellite of Gaofen-3 (GF-3) was launched in August 2016 under China High-resolution Earth Observation System (CEOS). GF-3 carries a multi-polarized C-band SAR with a highest spatial resolution of one meter, the most imaging modes in the word of twelve and a long designed lifespan of 8 years. Haiyang-2A (HY-2A), which was launched in August 2011, is the first Chinese marine dynamic environment satellite with a main payload of Ku-band microwave scatterometer (Jiang et al., 2012; Ye et al., 2015). One of the objectives of HY-2A scatterometer (HY-2A SCAT) is monitoring sea surface wind field of global ocean. 展开更多
关键词 SAR The first quantitative joint observation of typhoon by Chinese GF-3 SAR and HY-2A microwave scatterometer GF HY
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Conical Sonic-Supersonic Solutions for the 3-D Steady Full Euler Equations
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作者 Yanbo Hu Xingxing Li 《Communications on Applied Mathematics and Computation》 2023年第3期1053-1096,共44页
This paper concerns the sonic-supersonic structures of the transonic crossflow generated by the steady supersonic flow past an infinite cone of arbitrary cross section.Under the conical assumption,the three-dimensiona... This paper concerns the sonic-supersonic structures of the transonic crossflow generated by the steady supersonic flow past an infinite cone of arbitrary cross section.Under the conical assumption,the three-dimensional(3-D)steady Euler equations can be projected onto the unit sphere and the state of fluid can be characterized by the polar and azimuthal angles.Given a segment smooth curve as a conical-sonic line in the polar-azimuthal angle plane,we construct a classical conical-supersonic solution near the curve under some reasonable assumptions.To overcome the difficulty caused by the parabolic degeneracy,we apply the characteristic decomposition technique to transform the Euler equations into a new degenerate hyperbolic system in a partial hodograph plane.The singular terms are isolated from the highly nonlinear complicated system and then can be handled successfully.We establish a smooth local solution to the new system in a suitable weighted metric space and then express the solution in terms of the original variables. 展开更多
关键词 Three-dimensional(3-d)full Euler equations Conical flow Conical-sonic Characteristic decomposition Classical solution
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Adaptive Window Based 3-D Feature Selection for Multispectral Image Classification Using Firefly Algorithm
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作者 M.Rajakani R.J.Kavitha A.Ramachandran 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期265-280,共16页
Feature extraction is the most critical step in classification of multispectral image.The classification accuracy is mainly influenced by the feature sets that are selected to classify the image.In the past,handcrafte... Feature extraction is the most critical step in classification of multispectral image.The classification accuracy is mainly influenced by the feature sets that are selected to classify the image.In the past,handcrafted feature sets are used which are not adaptive for different image domains.To overcome this,an evolu-tionary learning method is developed to automatically learn the spatial-spectral features for classification.A modified Firefly Algorithm(FA)which achieves maximum classification accuracy with reduced size of feature set is proposed to gain the interest of feature selection for this purpose.For extracting the most effi-cient features from the data set,we have used 3-D discrete wavelet transform which decompose the multispectral image in all three dimensions.For selecting spatial and spectral features we have studied three different approaches namely overlapping window(OW-3DFS),non-overlapping window(NW-3DFS)adaptive window cube(AW-3DFS)and Pixel based technique.Fivefold Multiclass Support Vector Machine(MSVM)is used for classification purpose.Experiments con-ducted on Madurai LISS IV multispectral image exploited that the adaptive win-dow approach is used to increase the classification accuracy. 展开更多
关键词 Multispectral image modifiedfirefly algorithm 3-d feature extraction feature selection multiclass support vector machine CLASSIFICATION
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Electron Microscopic In-situ Observation for Preparation of Ultrafine La_2O_3 Nanophase Powder 被引量:1
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作者 高愈尊 李永洪 张泰宋 《Journal of Rare Earths》 SCIE EI CAS CSCD 1996年第3期206-209,共4页
In-situ observation in high voltage electron microscope(HVEM) was used to investigate transformation from amorphous La(OH)3 to nanophase La2O3. Electron diffraction pattern indicates that the transition temperature fr... In-situ observation in high voltage electron microscope(HVEM) was used to investigate transformation from amorphous La(OH)3 to nanophase La2O3. Electron diffraction pattern indicates that the transition temperature from La(OH)3 to nanophase La2O3 is 400 ℃. Particle sizes for nanophase La2O3 are from 20 to 50 nm. 展开更多
关键词 La_2O_3 NANOPHASE Insitu observation High voltage electron microscope
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鼻炎3号方联合鼻负压置换治疗急性鼻窦炎(胆腑郁热证)的研究报告
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作者 刘静丹 谢梁震 +2 位作者 王嘉乐 赵雨奇 周凌 《中国中医急症》 2024年第8期1354-1357,1368,共5页
目的观察鼻炎3号方联合鼻负压置换治疗急性鼻窦炎(胆腑郁热证)患者的临床疗效。方法98例患者随机分为观察组与对照组各49例,对照组予鼻腔负压置换治疗,观察组在对照组基础上予鼻炎3号方治疗,治疗周期均为2周。观察中医证候疗效、中医证... 目的观察鼻炎3号方联合鼻负压置换治疗急性鼻窦炎(胆腑郁热证)患者的临床疗效。方法98例患者随机分为观察组与对照组各49例,对照组予鼻腔负压置换治疗,观察组在对照组基础上予鼻炎3号方治疗,治疗周期均为2周。观察中医证候疗效、中医证候积分、视觉模拟量表(VAS)评分、鼻腔鼻窦结局测试-20(SNOT-20)量表、Lund-Mackey评分、炎性指标、安全性评价。结果观察组总有效率为91.84%,高于对照组的71.43%(P<0.05)。疗程结束后,两组中医证候积分、VAS评分、SNOT-20量表、Lund-Mackey评分、炎性指标[C反应蛋白(CRP)、白细胞计数(WBC)、中性粒细胞百分比(NEUT%)]均较治疗前下降(P<0.05),其中中医证候积分鼻涕、头痛、鼻分泌物、鼻黏膜充血4项,VAS评分脓涕项两组间差异无统计学意义(P>0.05),其余各项观察组下降程度更明显(P<0.05)。两组安全性指标差异无统计学意义(P>0.05)。结论鼻炎3号方联合鼻负压置换治疗急性鼻窦炎(胆腑郁热证)疗效显著,可有效改善中医证候,提高生活质量,减轻炎症反应,安全性良好。 展开更多
关键词 急性鼻窦炎 鼻炎3号方 胆腑郁热证 负压置换 临床观察
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