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Valley excitons in two-dimensional semiconductors

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National Science Review 2015年第1期2卷 57-70页

作者： Hongyi Yu xiaodong cui xiaodong Xu Wang Yao Department of Physics The University of Hong Kong Center of Theoretical and Computational Physics The University of Hong Kong Department of Physics University of Washington Department of Material Science and Engineering University of Washington

Monolayer group-VIB transition-metal dichalcogenides have recently emerged as a new class of semiconductors in the two-dimensional limit. he atractive properties include the visible range direct band gap ideal for exploring optoelectronic applications; the intriguing physics associated with spin and valley pseudospin of carriers which implies potentials for novel electronics based on these internal degrees of freedom; the exceptionally strong Coulomb interaction due to the two-dimensional geometry and the large efective masses. he physics of excitons, the bound states of electrons and holes, has been one of the most actively studied topics on these two-dimensional semiconductors, where the excitons exhibit remarkably new features due to the strong Coulomb binding, the valley degeneracy of the band edges and the valley-dependent optical selection rules for interband transitions. Here, we give a brief overview of the experimental and theoretical indings on excitons in two-dimensional transition-metal dichalcogenides,with focus on the novel properties associated with their valley degrees of freedom.

关键词： exciton valley physics two-dimensional semiconductor transition metal dichalcogenides

Surface organic modification of Fe_3O_4 nanoparticles by silane-coupling agents

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Rare Metals 2006年第z1期25卷 426-430页

作者： cui Sheng SHEN xiaodong LIN Benlan College of Material Science and Technology Nanjing University of Technology Nanjing 210009 China College of Material Science and Technology Nanjing University of Technology Nanjing 210009 China College of Material Science and Technology Nanjing University of Technology Nanjing 210009 China

Fe3O4 nanoparticles were prepared by chemistry co-precipitation and the mean crystal size was 17.9 nm measured by XRD. After it had been treated by silane-coupling agents KH570, magnetic micro-spheres dispersed in organic medium glycol were gained and the mean size of Fe3O4 nanopowders was 33.7 nm. So it can be concluded that magnetic micro-sphere is made of a few Fe3O4 crystals. Many factors of modification were researched, such as the time of ball milling, the content of Fe3O4 and the content of KH570. The modification of Fe3O4 is relative to the time of ball milling, but the dominant function is affected by the content of Fe3O4 and KH570. When the content of Fe3O4 is known, there is a suitable content of KH570. Different content of Fe3O4 will make the different suitable content of KH570, but the range of latter is less than former, which is relative to the distribution of KH570 on Fe3O4 surface or in the solution.

关键词： Fe3O4 nanoparticles organic modification silane-coupling agents

基于改进EMD方法与11/2谱的DEMON谱提取方法

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声学技术 2024年第2期43卷 260-267页

作者：高博超张群飞李岳珩崔晓东西北工业大学航海学院陕西西安710072 西北工业大学电子信息学院陕西西安710072

噪声的包络调制检测(Detection of Envelope Modulation on Noise,DEMON)谱分析技术已被广泛应用于特征提取领域,但经典DEMON谱提取中高频信号频段的选取会影响DEMON谱的提取效果。针对这一问题,文中首先运用经验模态分解(Empirical Mod... 详细信息

噪声的包络调制检测(Detection of Envelope Modulation on Noise,DEMON)谱分析技术已被广泛应用于特征提取领域,但经典DEMON谱提取中高频信号频段的选取会影响DEMON谱的提取效果。针对这一问题,文中首先运用经验模态分解(Empirical Mode Decomposition,EMD)方法获得一系列固有模态函数(Intrinsic Mode Function,IMF),依据各阶模态函数与原信号的相关程度,筛选出更具代表性的几阶固有模态函数进行解调,再对解调的结果运用11/2维谱分析方法进行谱分析以抑制高斯噪声,通过这种方法获得的DEMON谱信噪比优于传统方法。实测湖试数据分析结果表明,该改进方法可以有效地进行特征提取,结果优于经典DEMON谱分析方法;该改进方法具有一定的实用性,有利于进行后续目标分类识别。

关键词：特征提取经验模态分解(EMD) 固有模态函数 11/2维谱分析

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基于多尺度纹理特征的海底底质样本增强方法

海洋测绘 2024年第2期44卷 31-35页

作者：张少华胡海洋王朋程崔晓东王亚雪山东省第三地质矿产勘查院山东烟台264004 山东科技大学测绘与空间信息学院山东青岛266590

针对多波束海底底质分类模型构建受限于样本和特征对海底底质类型表征不足、模型稳定性差等问题,利用多尺度滑动窗口法提取声学纹理特征,结合K-均值聚类分析其精度,实现了多尺度纹理特征的优选,并利用多尺度纹理特征并辅以地形特征结合S... 详细信息

针对多波束海底底质分类模型构建受限于样本和特征对海底底质类型表征不足、模型稳定性差等问题,利用多尺度滑动窗口法提取声学纹理特征,结合K-均值聚类分析其精度,实现了多尺度纹理特征的优选,并利用多尺度纹理特征并辅以地形特征结合SLIC样本增强方法,实现了底质样本的有效扩充。同时,利用随机森林、BP神经网络、K最邻近、支持向量机等4种经典监督分类模型训练预测和评估所扩充的样本数据,最终总体分类精度均达到90%以上,kappa系数达到0.85以上。

关键词：海底底质分类反向散射强度多尺度纹理特征样本增强监督分类

Surface Organic Modification of Fe_3O_4 Magnetic Nanoparticles

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Journal of Wuhan University of Technology(Materials Science) 2008年第4期23卷 436-439页

作者： cui Sheng SHEN xiaodong LIN Benlan JIANG Guodong ZHANG Weihua College of Material Science and Technology Nanjing University of Technology Nanjing 210009 China

The surface organic modification of Fe3O4 nanoparticles with silane coupling reagent KH570 was studied. The modified and unmodified nanoparticles were characterized by FT-IR, XPS and TEM. The spectra of FT-IR and XPS revealed that KH570 was coated onto the surface of Fe3O4 nanoparticles to get Fe-O- Si bond and an organic coating layer also was formed. Fe3O4 nanoparticles were spheres partly with mean size of 18,8 nm studied by TEM, which was consistent with the result 17.9 nm calculated by Scherrer＇s equation. KH570 was adsorbed on surface and formed chemistry bond to be steric hindrance repulsion which prevented nanoparticles from reuniting. Then glycol-based Fe3O4 magnetic liquids dispersed stably was gained.

关键词： Fe3O4 nanoparticles KH570 surface organic modification chemical adsorb dispersivity

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原发于宫角的子宫内膜癌临床误诊原因探讨

临床误诊误治 2024年第16期37卷 21-23页

作者：崔晓东刘俊艳耿莉莉崔静静河北省沧州中西医结合医院麻醉科河北沧州061001 河北省沧州中西医结合医院妇科河北沧州061001

目的探讨原发于宫角的子宫内膜癌误诊为子宫肌瘤变性的原因及防范误诊措施,以降低误诊率。方法回顾分析2022年3月收治原发于宫角的子宫内膜癌误诊子宫肌瘤变性1例临床资料。结果本例因绝经3年、左下腹痛半年就诊,彩超提示左宫角囊实性... 详细信息

目的探讨原发于宫角的子宫内膜癌误诊为子宫肌瘤变性的原因及防范误诊措施,以降低误诊率。方法回顾分析2022年3月收治原发于宫角的子宫内膜癌误诊子宫肌瘤变性1例临床资料。结果本例因绝经3年、左下腹痛半年就诊,彩超提示左宫角囊实性占位性病变(子宫肌瘤变性?),查癌抗原125和癌胚抗原正常。后行宫腔刮出物病理学检查考虑子宫内膜样腺癌,手术病理示左宫角子宫内膜样腺癌Ⅲ级伴部分梭形细胞分化,结合免疫组化结果诊断为子宫内膜样腺癌Ⅲ期。误诊时间6 d。给予手术治疗,术后予紫杉醇联合卡铂化疗2个疗程,患者一般状态尚可,未见复发或转移,尚在随访中。结论原发于宫角的子宫内膜癌临床症状及影像学表现不典型,早期容易误诊为子宫肌瘤变性等疾病。对于绝经期宫角占位性病变者应考虑到多种疾病的可能,结合患者病史(包括现病史、既往史)、实验室检查、影像学检查及病理检查有助于降低误诊率。

关键词：子宫内膜癌腺癌子宫角误诊子宫肌瘤变性肿瘤标志物病理检查鉴别诊断

Boosting tribo-catalytic conversion of H_(2)O and CO_(2)by Co_(3)O_(4)nanoparticles through metallic coatings in reactors

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Journal of Advanced Ceramics 2023年第10期12卷 1833-1843页

作者： Xuchao Jia Hongbo Wang Hua Lei Chenyue Mao xiaodong cui Yong Liu Yanmin Jia Wenqing Yao Wanping Chen School of Physics and Technology Wuhan UniversityWuhan 430072China School of Science Xi’an University of Posts and TelecommunicationsXi’an 710061China Department of Chemistry Tsinghua UniversityBeijing 100084China

In recent years,more and more metal oxides have been finding critical tribo-catalytic ***,we have explored the tribo-catalytic conversion of H_(2)O and CO_(2)using Co_(3)O_(4)nanoparticles and obtained some surprising *** an as-received 150 mL glass reactor enclosed with 10 mL of H_(2)O,0.10 g of Co_(3)O_(4)nanoparticles,1 atm of CO_(2),and a Teflon magnetic rotary disk,we observed the production of as much as 57.41μmol/L of H_(2),0.15μmol/L of CH_(4),and 0.21μmol/L of CO after 5 h of magnetic *** coatings of Cu,Ni,SUS316,Ti,Nb,Mo,and W were further introduced on reactor bottoms *** those coatings of Ni,SUS316,Ti,and Nb,the reduction of CO_(2)was dramatically enhanced,and C_(2+)products of C_(2)H_(6)and C_(2)H_(4)were *** for the Ti coating,the amounts of H_(2)and CH_(4)were increased by 2 and 26 times from those for the glass bottom,respectively,and the amounts of C_(2)H_(6)and C_(2)H_(4)were very *** Co_(3)O_(4)nanoparticles were proven chemically stable under magnetic stirring in water,and hydroxyl radicals and superoxide radicals have been detected for the Co_(3)O_(4)nanoparticles under magnetic stirring through fluorescence spectroscopy and electron paramagnetic resonance spectroscopy *** findings not only reveal outstanding capability of Co_(3)O_(4)to generate multicarbon products from H_(2)O and CO_(2)through tribo-catalysis but also highlight a promising potential of tribo-catalysis as a whole to harness mechanical energy for addressing energy shortages and environmental pollution.

关键词： tribo-catalysis water splitting CO_(2)reduction Co_(3)O_(4)

Micropeptides: origins, identification, and potential role in metabolism-related diseases

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第12期24卷 1106-1122页

作者： Yirui LU Yutong RAN Hong LI Jiao WEN xiaodong cui Xiaoyun ZHANG Xiumei GUAN Min CHENG School of Basic Medicine Sciences Weifang Medical UniversityWeifang 261053China

With the development of modern sequencing techniques and bioinformatics, genomes that were once thought to be noncoding have been found to encode abundant functional micropeptides(miPs), a kind of small polypeptides. Although miPs are difficult to analyze and identify, a number of studies have begun to focus on them. More and more miPs have been revealed as essential for energy metabolism homeostasis, immune regulation, and tumor growth and development. Many reports have shown that miPs are especially essential for regulating glucose and lipid metabolism and regulating mitochondrial *** are also involved in the progression of related diseases. This paper reviews the sources and identification of miPs, as well as the functional significance of miPs for metabolism-related diseases, with the aim of revealing their potential clinical applications.

关键词： Energy metabolism Micropeptides Mitochondria Noncoding RNA(ncRNA) Small open reading frame(sORF)

基于深度学习的冠状动脉CTA自动后处理技术诊断冠心病的价值研究

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同济大学学报（医学版） 2024年第1期45卷 66-74页

作者：罗月倪炯崔晓东吕礼胡琦王培军同济大学附属同济医院医学影像科上海200065 同济大学医学院医学影像人工智能研究所上海200065

目的探讨一种基于深度学习(deep learning,DL)的冠状动脉CT血管成像(coronary computed tomography angiography,CCTA)人工智能(artificial intelligence,AI)辅助诊断系统诊断冠心病(coronary artery disease,CAD)的临床价值。方法回顾性分析4周内先后完成CCTA和侵入性冠状动脉血管造影(coronary angiography,CAG)检查的69例患者,共462个冠状动脉近端血管节段。比较AI辅助诊断技术和CCTA人工分析影像数据所用时间。分别在患者水平、血管节段水平评估AI和CCTA对CAD的诊断效能;在各血管节段水平对AI、CCTA诊断结果进行误差分析。结果 AI耗时明显低于CCTA[(5.5±0.9) min vs(14.2±1.8) min]。在患者水平和总血管节段水平,AI识别显著狭窄(狭窄程度≥50%)的灵敏度分别为97.9%、79.6%,阴性预测值分别为90.9%、93.2%,准确性分别为82.6%、80.5%;CCTA识别显著狭窄的灵敏度分别为96.6%、85.9%,阴性预测值分别为81.8%、92.9%,准确性分别为94.2%、91.6%;CCTA识别显著狭窄的准确性较高,AUC分别为0.984(95%CI:0.959~1.000)、0.960(95%CI:0.942~0.977),与CAG差异无统计学意义(均P>0.05);AI识别显著狭窄有一定准确性,AUC分别为0.864(95%CI:0.748~0.979)、0.823(95%CI:0.780~0.865),与CAG差异有统计学意义(均P<0.05)。在各血管节段水平,AI检测显著狭窄的准确性分别为89.9%、78.3%、92.8%、69.6%、60.9%、88.4%、85.4%。对于钙化斑块、混合斑块、非钙化斑块、心肌桥及血管解剖异常,AI分别漏诊11、20、29、7、2段,误诊7、3、5、1、5段;CCTA分别漏诊2、5、6、2、2段,误诊9、3、4、4、2段。结论基于DL的CCTA自动后处理技术能高效完成CCTA数据分析,有较高的CAD诊断效能,具有成为临床诊断CAD辅助工具的潜力。而人机结合可能有望进一步提高CAD的诊断效能。

关键词：人工智能深度学习冠心病冠状动脉CT血管成像