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单层蓝磷带电点缺陷的结构稳定性及电子性质

物理学报 2024年第13期73卷 269-276页

作者：马荣荣马晨蕊葛梅郭世祺张均锋山西师范大学物理与信息工程学院太原030031 海南师范大学物理与电子工程学院海口571158

作为一种新型的二维材料,蓝磷因其具有较高的载流子迁移率和较大的禁带宽度引起了研究者们极大的研究兴趣.近年来已有研究讨论了蓝磷中的结构缺陷,但是关于其缺陷带电性质的研究尚未见报道.本文利用基于密度泛函理论的第一性原理计算,... 详细信息

作为一种新型的二维材料,蓝磷因其具有较高的载流子迁移率和较大的禁带宽度引起了研究者们极大的研究兴趣.近年来已有研究讨论了蓝磷中的结构缺陷,但是关于其缺陷带电性质的研究尚未见报道.本文利用基于密度泛函理论的第一性原理计算,讨论了蓝磷SW(Stone Wales)缺陷、单空位(SV)缺陷、两种双空位缺陷(DV-1和DV-2)以及两种替位缺陷(OP和CP)的带电性质.利用带电缺陷体系能量依赖于晶胞尺寸的渐进表达式进行外推的方法,修正了蓝磷带电缺陷体系的形成能.研究结果表明,在所讨论的缺陷中,富O条件下OP具有最低的形成能,最稳定;而SV的离化能最小,最容易电离.引入的缺陷态会对蓝磷的禁带宽度产生影响.缺陷带电过程中,缺陷态位置变化导致绝大部分缺陷转变为深能级缺陷.本研究结果对缺陷工程在二维材料上的应用提供了一定的理论指导.

关键词：第一性原理计算蓝磷带电缺陷离化能

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基于特征金字塔网络的余弦四元组哈希图像检索方法

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计算机工程与设计 2024年第7期45卷 2127-2133页

作者：盖枚岭张辉辉秦琦冰潍坊学院计算机工程学院山东潍坊261061 中国海洋大学信息科学与工程山东青岛266000

为提高哈希图像检索的准确性,设计并提出一种基于特征金字塔网络的余弦四元组哈希图像检索方法,增强生成哈希编码的区分性。提出一种基于特征金字塔网络的特征提取器,提取到包含多层视觉信息和语义信息的图像特征描述符。设计基于余弦... 详细信息

为提高哈希图像检索的准确性,设计并提出一种基于特征金字塔网络的余弦四元组哈希图像检索方法,增强生成哈希编码的区分性。提出一种基于特征金字塔网络的特征提取器,提取到包含多层视觉信息和语义信息的图像特征描述符。设计基于余弦度量的四元组排序损失,使哈希码能够保持相似近邻关系;引入分类损失和二进制约束损失,使离散编码包含更多语义信息。实验结果表明,所提模型具有更好的检索性能。

关键词：深度哈希图像检索特征金字塔余弦度量四元组损失分类损失二进制约束损失

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拉曼光谱技术在脑胶质瘤检测中的应用研究

中国光学（中英文） 2024年第5期17卷 995-1013页

作者：葛梅兰王与烨李海滨徐德刚姚建铨天津大学精密仪器与光电子工程学院天津300072 天津大学光电信息技术教育部重点实验室天津300072

脑胶质瘤是一种常见的颅内原发性肿瘤,具有治愈率低、复发率高等特点。脑胶质瘤边界的精准识别是减少患者术后复发、改善愈后状况的重要前提。因此,发展快速、高灵敏度、无标记的脑胶质瘤诊断方法具有重要的临床意义。拉曼光谱技术作为... 详细信息

脑胶质瘤是一种常见的颅内原发性肿瘤,具有治愈率低、复发率高等特点。脑胶质瘤边界的精准识别是减少患者术后复发、改善愈后状况的重要前提。因此,发展快速、高灵敏度、无标记的脑胶质瘤诊断方法具有重要的临床意义。拉曼光谱技术作为一种指纹谱,能够在分子水平上反映物质的化学和结构信息,已经在脑胶质瘤的定性定位识别中表现出巨大的应用前景。本文首先介绍了不同种类的拉曼光谱技术,其次梳理了拉曼光谱技术在脑胶质瘤中的研究现状,最后对拉曼光谱技术在脑胶质瘤检测中的未来发展进行展望。

关键词：拉曼光谱脑胶质瘤检测识别

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Optical polarization characteristics for AlGaN-based light-emitting diodes with AlGaN multilayer structure as well layer

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Chinese Physics B 2021年第4期30卷 535-541页

作者： Lu Xue Yi Li mei ge mei-Yu Wang You-Hua Zhu School of Information Science and Technology&Tongke School of Microelectronics Nantong UniversityNantong 226019China

The optical properties of AlGaN-based quantum well(QW)structure with two coupled thin well layers are investigated by the six-by-six K-P *** with the conventional structure,the new structure,especially the one with lower Al-content in the barrier layer,can enhance the TE-/TM-polarized total spontaneous emission rate due to the strong quantum confinement and wide recombination *** the conventional QW structure,the reduction of well thickness can lead the degree of polarization(DOP)to decrease and the internal quantum efficiency(IQE)to *** using the coupled thin well layers,the DOP for the structure with high Al-content in the barrier layer can be improved,while the DOP will further decrease with low Al-content in the barrier *** can be attributed to the band adjustment induced by the combination of barrier height and well layer *** IQE can also be further enhanced to 14.8%-20.5%for various Al-content of barrier layer at J=100 A/cm^(2).In addition,the efficiency droop effect can be expected to be suppressed compared with the conventional structure.

关键词： Al Ga N-based quantum well K-P method internal quantum efficiency degree of polarization

Enhanced valley splitting of WSe_(2)in twisted van der Waals WSe_(2)/CrI_(3)heterostructures

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npj Computational Materials 2022年第1期8卷 277-283页

作者： mei ge Han Wang Jizheng Wu Chen Si Junfeng Zhang Shengbai Zhang School of Physics and Information Engineering Shanxi Normal UniversityTaiyuanChina Chemical Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCAUSA School of Materials Science and Engineering Beihang UniversityBeijingChina Department of Physics Applied Physicsand AstronomyRensselaer Polytechnic InstituteTroyNYUSA

Van der Waals(vdW)heterostructures composed of different two-dimensional(2D)materials offer an easily accessible way to combine properties of individual materials for *** to the discovery of a set of unanticipated physical phenomena,the twisted 2D vdW heterostructures have gained considerable attention ***,we report enhanced valley splitting in twisted 2D vdW WSe_(2)/CrI_(3)*** particular,the splitting can be 1200%(or 5.18 meV)of the value for a non-twisted *** to the k·p model,this value is equivalent to a~20 T external magnetic field applied perpendicular to the 2D *** thermodynamic stability of 2D vdW WSe_(2)/CrI_(3)heterostructures,on the other hand,depends linearly on the interlayer twisting angle.

关键词： twisted splitting gained

利培酮联用叶酸对精神分裂症患者脑源性神经营养因子与炎性细胞因子的影响

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中国现代药物应用 2024年第15期18卷 96-99页

作者：柯龙婷孙美鸽李益群福建省泉州市第三医院精神科第七病区 362000福建省泉州市第三医院精神科第七病区362000

目的观察利培酮联用叶酸对精神分裂症患者脑源性神经营养因子与炎性细胞因子的影响。方法85例首发精神分裂症患者,按照随机平行对照法分为对照组(42例)与研究组(43例)。对照组使用利培酮治疗,研究组使用叶酸+利培酮治疗。比较两组治疗... 详细信息

目的观察利培酮联用叶酸对精神分裂症患者脑源性神经营养因子与炎性细胞因子的影响。方法85例首发精神分裂症患者,按照随机平行对照法分为对照组(42例)与研究组(43例)。对照组使用利培酮治疗,研究组使用叶酸+利培酮治疗。比较两组治疗前后炎性细胞因子[白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)]、脑源性神经营养因子(BDNF)、同型半胱氨酸(Hcy)、精神分裂程度[阳性与阴性症状量表(PANSS)评分]、暴力行为[外显攻击行为量表(MOAS)评分]、认知功能[韦氏成人智力量表(WAIS-RC)评分]、社会功能[住院精神患者社会功能评定量表(SSPI)评分]。结果治疗3个月后,研究组患者的IL-6、TNF-α水平分别为(33.86±3.07)、(26.93±2.38)pg/ml,显著低于对照组的(38.15±3.56)、(32.67±2.93)pg/ml(P<0.05)。治疗3个月后,研究组的BDNF水平(593.18±56.02)pg/ml高于对照组的(527.46±49.37)pg/ml,Hcy水平(28.76±2.54)μmol/L低于对照组的(34.13±3.15)μmol/L(P<0.05)。治疗3个月后,研究组患者的PANSS、MOAS评分分别为(53.62±5.04)、(8.95±0.86)分,均显著低于对照组的(60.97±5.75)、(10.27±0.98)分(P<0.05)。治疗3个月后,研究组患者的WAIS-RC、SSPI评分分别为(206.91±17.85)、(33.25±3.01)分,均高于对照组的(185.26±15.37)、(28.07±2.54)分(P<0.05)。结论利培酮联用叶酸治疗精神分裂症,有利于改善BDNF与炎性细胞因子水平,减轻患者的临床症状和暴力行为,改善其认知功能和社会功能,具有较好的治疗效果。

关键词：利培酮叶酸精神分裂症脑源性神经营养因子炎性细胞因子

Assessment of the potential toxicity of insecticidal compounds to Peristenus spretus,a parasitoid of mirid bugs

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Journal of Integrative Agriculture 2022年第5期21卷 1424-1435页

作者： ZHAO Man LI Yun-he NIU Lin-lin CHEN Lin LIANG ge-mei State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China College of Plant Protection Henan Agricultural UniversityZhengzhou 450002P.R.China

With the increased cultivation of Bt crops in China,Apolygus lucorum and other mirid bugs have emerged as important agricultural pests because they are insensitive to the Bt *** addition,the reduction of pesticide applications after planting Bt crops also increases the severity of mirid bug *** spretus is a parasitoid of mirid nymphs,but its sensitivity to Bt proteins is not *** the current study,we developed a dietary exposure assay to assess the effects of Bt proteins(Cry1Ab,Cry1Ac,Cry1F,Cry2Aa,and Cry2Ab)on *** adults using a diet consisting of a 10% honey solution with or without Bt proteins at 400μg g^(-1) *** results showed that the survival and reproduction of *** adults were reduced by the cysteine protease inhibitor E-64(a positive control)but were not affected by any of the five Bt *** activities of digestive,detoxifying,and antioxidant enzymes in *** were also unaffected by diets containing the Cry proteins,but they were significantly affected by the diet containing *** then developed a tritrophic bioassay to determine the effects of the five Bt proteins on *** larvae and *** this assay,*** nymphs fed an artificial diet containing Cry proteins were used as the hosts for *** results of the tri-trophic assay indicated that neither the pupation rate nor the eclosion rate of the *** parasitoids were significantly affected by the presence of high concentrations of Bt proteins in the parasitized *** *** overall results indicate that these two assays can be used to evaluate the toxicity of insecticidal compounds to *** and that the tested Cry proteins are not toxic to ***.

关键词： transgenic crops plant bugs parasitic natural enemy Cry proteins non-target risk assessment

Effect of surface plasmon coupling with radiating dipole on the polarization characteristics of AlGaN-based light-emitting diodes

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Chinese Physics B 2022年第7期31卷 573-578页

作者： Yi Li mei ge meiyu Wang Youhua Zhu Xinglong Guo School of Information Science and Technology&Tongke School of Microelectronics Nantong UniversityNantong 226019China

The optical polarization characteristics of surface plasmon(SP)coupled Al Ga N-based light emitting diodes(LEDs)are investigated theoretically by analyzing the radiation recombination process and scattering process *** the Al_(0.5)Ga_(0.5)N/Al/Al_(2)O_(3)slab structure,the relative intensity of TE-polarized and TM-polarized spontaneous emission(SE)rate into the SP mode obviously depends on the thickness of the Al *** calculation results show that TM dominated emission will be transformed into TE dominated emission with the decrease of the Al thickness,while the emission intensities of both TE/TM polarizations will decrease *** addition,compared with TM polarized emission,TE polarized emission is easier to be extracted by SP *** the Al_(0.5)Ga_(0.5)N/Al nano-particle structure,the ratio of transmittance for TE/TM polarized emission can reach~3.06,while for the Al free structure,it is only ***,the degree of polarization of SP coupled LED can be improved by the reasonable structural design.

关键词： surface plasmon AlGaN-based light emitting diodes FDTD K-P method

Performance of Three Adelphocoris spp.(Hemiptera: Miridae) on Flowering and Non-flowering Cotton and Alfalfa

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Journal of Integrative Agriculture 2014年第8期13卷 1727-1735页

作者： GAO Zhen PAN Hong-sheng LIU Bing LU Yan-hui LIANG ge-mei State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences

The genus Adelphocoris（Hemiptera： Miridae） is a group of key insect pests in cotton fields in China that includes three dominant species： A. suturalis（Jakovlev）, A. lineolatus（Goeze） and A. fasciaticollis（Reuter）. Previous field surveys have found that adults of these Adelphocoris species usually move onto specific host plants when the plants enter the flowering stage. To determine the potential trade-offs for this host-plant preference behavior, the performance of these three Adelphocoris spp. on flowering and non-flowering cotton and alfalfa were compared in the laboratory. The results showed that Adelphocoris spp. had significantly higher nymphal developmental and survival rates, along with increased adult longevity and fecundity on flowering cotton and alfalfa than on non-flowering plants of either species. In addition, compared with cotton plants, alfalfa generally promoted better performance of these three Adelphocoris species, especially for A. lineolatus. Simple correlation analysis indicated that female adult longevity was positively correlated to male adult longevity and female fecundity, and female fecundity was positively correlated to nymphal development and survival rates. This study demonstrated a positive correlation between adult preference and offspring/adult performance for all three Adelphocoris species, with no evidence of any trade-offs for this preference for flowering host plants. These findings support the hypothesis that hemimetabolous insects such as mirid bugs have positive adult preference-adult/nymphal performance relationships, which is likely due to the similar feeding habits and nutritional requirements of adults and nymphs.

关键词： Adelphocoris lineolatus Adelphocoris suturalis Adelphocoris fasciaticollis preference-performance relationship cotton alfalfa flowering stage