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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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Pt nanoclusters modified porous g-C_(3)N_(4)nanosheets to significantly enhance hydrogen production by photocatalytic water reforming of methanol
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作者 Yi-Fei Liang Jin-Rong Lu +2 位作者 Shang-Kun Tian Wen-Quan Cui Li Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期40-50,共11页
For the use of green hydrogen energy,it is crucial to have efficient photocatalytic activity for hydrogen generation by water reforming of methanol under mild conditions.Much attention has been paid to gC_(3)N_(4)as a... For the use of green hydrogen energy,it is crucial to have efficient photocatalytic activity for hydrogen generation by water reforming of methanol under mild conditions.Much attention has been paid to gC_(3)N_(4)as a promising photocatalyst for the generation of hydrogen.To improve the separation of photogenerated charge,porous nanosheet g-C_(3)N_(4)was modified with Pt nanoclusters(Pt/g-C_(3)N_(4))through impregnation and following photo-induced reduction.This catalyst showed excellent photocatalytic activity of water reforming of methanol fo r hydrogen production with a 17.12 mmol·g^(-1)·h^(-1)rate at room temperature,which was 311 times higher than that of the unmodified g-C_(3)N_(4).The strong interactions of Pt-N in Pt/g-C_(3)N_(4)constructed effective electron transfer channels to promote the separation of photogenerated electrons and holes effectively.In addition,in-situ infrared spectroscopy was used to investigate the intermediates of the hydrogen production reaction,which proved that methanol and water eventually turn into H_(2)and CO_(2)via formaldehyde and formate.This study provides insights for understanding the photocatalytic hydrogen production in the water reforming of methanol. 展开更多
关键词 Water reforming of methanol Photocatalysis g-C_(3)N_(4) Pt nanoclusters Hydrogen production
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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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以生物样本库为基础的“5+3”临床医学科研教学改革探索
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作者 谢波 许斌 《中国高等医学教育》 2024年第6期15-16,共2页
面对日益增长的高质量医疗服务需求与医学生培养质量低下、培养周期长的矛盾,国家和学界提出“5+3”一体化临床医学专业培养模式。在近7年的培养实践中,该模式孕育了大批基础扎实、临床技能娴熟的规培医生,但也暴露其科研创新思维和能... 面对日益增长的高质量医疗服务需求与医学生培养质量低下、培养周期长的矛盾,国家和学界提出“5+3”一体化临床医学专业培养模式。在近7年的培养实践中,该模式孕育了大批基础扎实、临床技能娴熟的规培医生,但也暴露其科研创新思维和能力的匮乏,这表明“5+3”一体化教育模式需要对科研能力方面进行深化改革。文章探索了以生物样本库为基础的“5+3”一体化临床医学科研思维和能力的改革方案。 展开更多
关键词 “5+3”一体化 临床医学 生物样本库 科研素质 教学改革
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基于3D打印技术的甲烷水蒸气重整研究
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作者 李聪 余冉 +3 位作者 刘太楷 邓春明 邓畅光 刘敏 《材料导报》 EI CAS CSCD 北大核心 2024年第10期36-44,共9页
天然气(主要成分为甲烷)重整是天然气高效清洁利用的重要途径,重整获得富含氢气的重整气,可供固体氧化物燃料电池进行高效发电。甲烷水蒸气重整需要反应器以及负载其上的重整催化剂,基于3D打印技术的多孔结构具有良好的耐高温、抗氧化... 天然气(主要成分为甲烷)重整是天然气高效清洁利用的重要途径,重整获得富含氢气的重整气,可供固体氧化物燃料电池进行高效发电。甲烷水蒸气重整需要反应器以及负载其上的重整催化剂,基于3D打印技术的多孔结构具有良好的耐高温、抗氧化和结构稳定性等特点,负载Ni基催化剂用于甲烷催化重整可有效提升反应器稳定性,但相关研究较少。采用浸渍法将Ni-CeO_(2)/γ-Al_(2)O_(3)催化剂负载于3D打印制备的多孔结构和金属泡沫反应器,通过催化剂形貌、分布规律、相结构以及热稳定性的表征,研究了重整反应温度、浆料配比、反应器结构等因素对甲烷水蒸气重整效果的影响。结果显示,催化剂的最佳配比是PVA含量为3.5%(若无特殊说明,均为质量分数),Ni含量为19%,CeO_(2)和γ-Al_(2)O_(3)的含量分别为16%和2.5%。重整测试结果表明,负载催化剂前,重整反应温度低于700℃时,Inconel625和泡沫Ni多孔反应器重整得到的氢气浓度均低于13%(体积分数),而重整反应温度高于800℃时,Inconel625和泡沫Fe多孔反应器重整效果接近,但Inconel625稳定性优于泡沫Fe;负载催化剂后,NCA-I(Inconel625)样品始终表现出低于NCA-N(泡沫Ni)和NCA-F(泡沫Fe)的重整性能,这主要是因为NCA-I含有较多的Cr元素,高温下Cr氧化生成Cr2O3氧化膜,阻碍了反应气和Ni的接触,但测试后NCA-I样品表现出优异的稳定性,无明显脆化和断裂现象,可有效提升重整反应器的稳定性。 展开更多
关键词 甲烷水蒸气重整 反应器 催化剂 Ni-CeO_(2)/γ-Al_(2)O_(3) 3D打印
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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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Al_(2)O_(3)前驱体对Cu/ZnO/Al_(2)O_(3)催化甲醇重整制氢性能的影响
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作者 黄敏 薄其飞 +5 位作者 李娟 乔靖萱 袁善良 张彪 陈洪林 蒋毅 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第10期1443-1452,共10页
采用共沉淀法制备了一系列Cu/ZnO/Al_(2)O_(3)催化剂,通过XRD、BET、H_(2)-TPR、N_(2)O化学吸附、XPS表征技术,研究了Al_(2)O_(3)前驱体对催化剂结构的影响,同时对其在甲醇重整制氢中的性能进行了考察。结果表明,当Al^(3+)与Cu^(2+)、Zn... 采用共沉淀法制备了一系列Cu/ZnO/Al_(2)O_(3)催化剂,通过XRD、BET、H_(2)-TPR、N_(2)O化学吸附、XPS表征技术,研究了Al_(2)O_(3)前驱体对催化剂结构的影响,同时对其在甲醇重整制氢中的性能进行了考察。结果表明,当Al^(3+)与Cu^(2+)、Zn^(2+)同时共沉淀时,Al^(3+)对碱式碳酸盐中Cu^(2+)-Zn^(2+)部分取代生成类水滑石结构,增强了Zn-Al之间的相互作用。相反,在Cu^(2+)、Zn^(2+)完成共沉淀后,引入Al_(2)O_(3)前驱体对消除Al^(3+)对碱式碳酸盐中Cu-Zn取代的不良影响具有积极作用,有利于促进Cu-ZnO间的相互作用、CuO物种的分散和催化剂的还原,进一步促进表面Cu的分散,有利于其活性的提升。其中,以拟薄水铝石为铝源制备的催化剂呈现出优异的活性。在水醇物质的量比为1.2,反应温度为493 K的条件下,甲醇转化率可达94.8%,H_(2)时空收率可达97.5 mol/(kg·h),并且连续运行25 h其活性仍保持相对稳定。在反应条件下,经过723 K的10 h热处理后,该催化剂的活性损失率仅为5.37%。 展开更多
关键词 Al_(2)O_(3)前驱体 Cu/ZnO/Al_(2)O_(3)催化剂 甲醇水蒸气重整 热稳定性
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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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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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Ni/ZrO_(2)-Al_(2)O_(3)催化剂催化沼气蒸汽重整制氢性能研究
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作者 张中亮 刘吉 +5 位作者 马宗虎 胡锶菡 冯冰 胡斌 李凯 陆强 《低碳化学与化工》 CAS 北大核心 2024年第9期19-25,32,共8页
沼气蒸汽重整是重要的制氢方式,开发高效稳定的催化剂是其规模化应用的重要环节。基于此,采用连续浸渍法制备了一系列基于ZrO_(2)-Al_(2)O_(3)复合载体的Ni基催化剂,对其进行了沼气蒸汽重整制氢催化性能测试。利用N_(2)吸/脱附、XRD等... 沼气蒸汽重整是重要的制氢方式,开发高效稳定的催化剂是其规模化应用的重要环节。基于此,采用连续浸渍法制备了一系列基于ZrO_(2)-Al_(2)O_(3)复合载体的Ni基催化剂,对其进行了沼气蒸汽重整制氢催化性能测试。利用N_(2)吸/脱附、XRD等表征方法,分析了催化剂的织构性质、晶相组成等。探究了催化剂的物理结构和化学性质对沼气蒸汽重整制氢的影响机制,并探讨了焙烧温度与金属助剂Fe对催化剂催化性能的影响。结果表明,在700°C、空速12000 h^(-1)条件下,焙烧温度为550°C制得的Ni/ZrO_(2)-Al_(2)O_(3)表现出突出的催化性能,CH_(4)转化率和H_(2)产率分别稳定在89.94%和81.49%。ZrO_(2)-Al_(2)O_(3)复合载体相比于Al_(2)O_(3)载体增大了催化剂的比表面积,促进了平均粒径较小的Ni在载体表面的高度分散,进而提高了催化剂的催化沼气蒸汽重整制氢性能。焙烧温度可以调控催化剂的比表面积和孔体积,焙烧温度为550°C制得的Ni/ZrO_(2)-Al_(2)O_(3)的比表面积和孔体积比焙烧温度为700°C制得的Ni/ZrO_(2)-Al_(2)O_(3)大。Fe与ZrO_(2)的耦合改性提升了催化剂的还原性能,生成了更多高活性Ni^(0),有利于甲烷干重整制氢反应的发生,调控了气体产物中的n_(H_(2))/n_(CO)。 展开更多
关键词 沼气 重整制氢 ZrO_(2)-Al_(2)O_(3)复合载体 NI基催化剂
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Void Morphology in 3-D Braided Preform/phenolic Composites 被引量:1
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作者 吴晓青 郭启微 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期539-543,共5页
Improved Resin Transfer Molding (RTM) technology and equipment were established.Void content and morphology of the 3-D braided preform/phenolic composite were investigated using different RTM processes.The results sho... Improved Resin Transfer Molding (RTM) technology and equipment were established.Void content and morphology of the 3-D braided preform/phenolic composite were investigated using different RTM processes.The results showed that void content of the vacuum and compression co-assisted RTM process was the lowest.Void morphologies of the specimen cross-section were analyzed with metallographic microscope.In traditional RTM process,the crack of cross-section was in evidence.In vacuum assisted RTM process,the void shape was divided into three categories:irregular crack,triangle,rotundity and ellipse.The most voids distributed in resin rich areas and were observed as large void based on equivalent diameter.In compression assisted RTM,vacuum and compression co-assisted RTM process,the polygonal voids mostly existed inter tows.Void size was mainly intermediate and small based equivalent diameter separately. 展开更多
关键词 3-d braided preform phenolic resin void morphology RTM
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A"messenger zone hypothesis"based on the visual three-dimensional spatial distribution of motoneurons innervating deep limb muscles
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作者 Chen Huang Shen Wang +3 位作者 Jin Deng Xinyi Gu Shuhang Guo Xiaofeng Yin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1559-1567,共9页
Coordinated contraction of skeletal muscles relies on selective connections between the muscles and multiple classes of the spinal motoneuro ns.Howeve r,current research on the spatial location of the spinal motoneuro... Coordinated contraction of skeletal muscles relies on selective connections between the muscles and multiple classes of the spinal motoneuro ns.Howeve r,current research on the spatial location of the spinal motoneurons innervating differe nt muscles is limited.In this study,we investigated the spatial distribution and relative position of different motoneurons that control the deep muscles of the mouse hindlimbs,which were innervated by the obturator nerve,femoral nerve,inferior gluteal nerve,deep pe roneal nerve,and tibial nerve.Locations were visualized by combining a multiplex retrograde tracking technique compatible with three-dimensional imaging of solvent-cleared o rgans(3DISCO)and 3-D imaging technology based on lightsheet fluorescence microscopy(LSFM).Additionally,we propose the hypothesis that"messenger zones"exist as interlaced areas between the motoneuron pools that dominate the synergistic or antagonist muscle groups.We hypothesize that these interlaced neurons may participate in muscle coordination as messenger neurons.Analysis revealed the precise mutual positional relationships among the many motoneurons that innervate different deep muscles of the mouse.Not only do these findings update and supplement our knowledge regarding the overall spatial layout of spinal motoneurons that control mouse limb muscles,but they also provide insights into the mechanisms through which muscle activity is coordinated and the architecture of motor circuits. 展开更多
关键词 3-d imaging MOTONEURONS multiple retrograde tracing muscle coordination skeletal muscle spatial distribution optical tissue clearing
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关于“5+3”一体化模式下口腔医学本科生科研能力及培养现状的问卷调查分析与研究
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作者 鲁译暄 周泽堃 +4 位作者 苏楷欣 聂倩 潘小曼 张帆 刘欧胜 《中国高等医学教育》 2024年第7期31-33,共3页
口腔医学专业“5+3”一体化是我国近年来主要的教学模式。“双轨合一”的制度下,专业型研究生由于临床实践要求提高,科研培养时间被压缩。如何提高学生科研能力是“5+3”一体化口腔医学教学改革的难点。通过调查问卷的方式,以7所高校中... 口腔医学专业“5+3”一体化是我国近年来主要的教学模式。“双轨合一”的制度下,专业型研究生由于临床实践要求提高,科研培养时间被压缩。如何提高学生科研能力是“5+3”一体化口腔医学教学改革的难点。通过调查问卷的方式,以7所高校中“5+3”一体化学生为调研对象,综合评估其科研认知、科研能力、科研经历等,根据问卷结果结合实际提出教学模式改革建议。 展开更多
关键词 “5+3”一体化 口腔医学 科研 问卷调查 教学改革
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