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铁磁物质中有杂质势时束缚磁极化子产生的讨论
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作者 刘涛 黄书文 +1 位作者 范云霞 汪克林 《中国科学技术大学学报》 CAS CSCD 北大核心 2006年第7期747-754,共8页
对铁磁物质中束缚极化子的存在与介质中有无杂质势密切相关的规律进行了系统的变分计算.在变分计算前,用Schwinger的角动量谐振子理论将其变换为载流子与两类玻色子耦合的问题,计算后得到的结论与普遍的看法一致.计算结果给出了杂质势... 对铁磁物质中束缚极化子的存在与介质中有无杂质势密切相关的规律进行了系统的变分计算.在变分计算前,用Schwinger的角动量谐振子理论将其变换为载流子与两类玻色子耦合的问题,计算后得到的结论与普遍的看法一致.计算结果给出了杂质势的强弱对束缚极化子形成的影响、半宽度的变化规律和用有限格点数的晶体代替实际晶体作近似计算的条件. 展开更多
关键词 束缚极化子 杂质势 模拟退火 铁磁物质
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掺杂反式聚乙炔中Site-type杂质势的唯象模型
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作者 贾荣谊 阎立根 王德民 《北京大学学报(自然科学版)》 CAS CSCD 北大核心 1996年第1期55-60,共6页
利用SSH模型讨论了Site-type杂质势对反式聚乙炔(trans-PA)电子态的影响。具体计算表明:对各向同性情况,Site-fype杂质势破坏了电子能谱的对称性,并使孤子能级发生移动,随着杂质离子与反式聚乙炔链间距的变化,它将引起孤子能级的变动。... 利用SSH模型讨论了Site-type杂质势对反式聚乙炔(trans-PA)电子态的影响。具体计算表明:对各向同性情况,Site-fype杂质势破坏了电子能谱的对称性,并使孤子能级发生移动,随着杂质离子与反式聚乙炔链间距的变化,它将引起孤子能级的变动。但不影响孤子局域化程度;而各向异性Site-type杂质势的不均匀性对trans-PA的电子能谱及孤子局域化程度影响较大。 展开更多
关键词 反式聚乙炔链 SSH模型 杂质势 聚乙炔 唯象模型
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浅杂质势与窄量子阱的耦合作用 被引量:1
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作者 朱嘉麟 《物理学报》 SCIE EI CAS CSCD 北大核心 1989年第7期1093-1102,共10页
本文采用一种新的变分波函数描述GaAs/Ga_(1-x)Al_xAs窄量子阱中的浅施主基态,并计算了杂质基态波函数和结合能。计算所得数值结果表明正确考虑窄量子阱与杂质势间的耦合作用是极为重要的。
关键词 量子阱 杂质势 耦合作用 半导体
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非对称高斯受限势量子阱中强耦合极化子基态的杂质效应 被引量:2
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作者 苗秀娟 梁志辉 肖景林 《内蒙古民族大学学报(自然科学版)》 2017年第5期374-377,共4页
采用Huybrechts的线性组合算符方法,从理论上研究了非对称高斯受限势量子阱中强耦合极化子的基态能量的杂质效应.然后导出了极化子的基态能量随着电子-类氢杂质之间的库仑杂质势强度、电子-声子耦合强度、非对称高斯受限势的高度和受限... 采用Huybrechts的线性组合算符方法,从理论上研究了非对称高斯受限势量子阱中强耦合极化子的基态能量的杂质效应.然后导出了极化子的基态能量随着电子-类氢杂质之间的库仑杂质势强度、电子-声子耦合强度、非对称高斯受限势的高度和受限势宽度的依赖关系.取通常的极化子单位进行数值计算,研究结果表明:高斯受限势量子阱中强耦合极化子的基态能量的绝对值是库仑杂质势的强度、电子-声子耦合强度、高斯受限势的高度和高斯受限势的宽度的增函数. 展开更多
关键词 非对称高斯受限量子阱 库仑杂质势 线性组合算符 基态能量
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非对称高斯势量子阱中强耦合极化子平均声子数的杂质效应 被引量:1
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作者 何颖卓 梁志辉 肖景林 《内蒙古民族大学学报(自然科学版)》 2017年第5期378-381,共4页
采用线性组合算符研究了非对称高斯受限势量子阱中强耦合极化子的平均声子数的杂质效应.导出了平均声子数随库仑杂质势强度、电子-声子耦合强、非对称高斯受限势的高度和受限势宽度的依赖关系.应用极化子单位进行数值计算,计算结果表明... 采用线性组合算符研究了非对称高斯受限势量子阱中强耦合极化子的平均声子数的杂质效应.导出了平均声子数随库仑杂质势强度、电子-声子耦合强、非对称高斯受限势的高度和受限势宽度的依赖关系.应用极化子单位进行数值计算,计算结果表明:平均声子数是库仑杂质势强度、电子-声子耦合强度和高斯势的高度的增函数,而它是受限势宽度的减函数. 展开更多
关键词 非对称高斯受限量子阱 库仑杂质势 线性组合算符 平均声子数
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用平面波法计算Si—nipi掺杂超晶格的电子态
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作者 陈积伟 黄和鸾 《辽宁大学学报(自然科学版)》 CAS 1988年第4期28-33,共6页
本文用平面波法自洽地计算了Si-nipi掺杂超晶格的电子态。当di→0时,对称性较高的<100>、<110>和<111>方向计算的结果与在正空间用各向同性模型计算的结果相比较,其有效带隙的变化规律基本一致,说明用平面波法计算Si-... 本文用平面波法自洽地计算了Si-nipi掺杂超晶格的电子态。当di→0时,对称性较高的<100>、<110>和<111>方向计算的结果与在正空间用各向同性模型计算的结果相比较,其有效带隙的变化规律基本一致,说明用平面波法计算Si-nipi超晶格的电子态是行之有效的。 展开更多
关键词 掺杂超晶格 SI nipi 电子态 面波法 自洽 简并度 矩阵元 杂质势 电子空穴
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Genetic Improvement Progress and Productive Effect of Rapeseed in Henan Province 被引量:1
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作者 朱家成 张书芬 +8 位作者 张书法 王建平 文雁成 何俊平 曹金华 蔡东芳 赵磊 王东国 隋天显 《Agricultural Science & Technology》 CAS 2017年第6期979-983,1006,共6页
The research progress and major achievements on genetic breeding, het- erosis utilization of rapeseed in Henan Province were summarized, with the aim to provide technical guidance for rapeseed genetic breeding in the ... The research progress and major achievements on genetic breeding, het- erosis utilization of rapeseed in Henan Province were summarized, with the aim to provide technical guidance for rapeseed genetic breeding in the future work. Faced with the problems of lack of special varieties, highly demand for healthy oil and high production cost in rapeseed production in recent years, the breeding goals of rapeseed have been adjusted from high yield, high quality and disease resistance to high oil, high oleic acid, adaptative to mechanization, late planting resistance. The breeding technologies mainly focused on the isolated microspore culture, molecular marker assisted selection, and the corresponding high efficiency technical systems were constructed. The innovative research on excellent germplasm resources were carried on, which created and established breeding populations and distinctive new germplasm resources with diverse variations such as high oil content, high oleic acid content and low linolenic acid, cold resistance, drought resistance, pod shatter resistance and different flower color variations. A series of rapeseed hybrids of dou- ble low varieties with strong heterosis and high oil contents were released and these hybrids significantly improved seed yield, quality and resistance. The average yield of rapeseed in Henan Province was 22.49% higher than the national average yield in 2003-2015. All of the achievements provided strong technical support for the upgrading of rapeseed varieties and increasing both production and income. 展开更多
关键词 RAPESEED Genetic improvement HETEROSIS Double low Germplasm in- novation
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Analysis of Heterosis, Combining Ability and Heritability of Cadmium Content in Brown Rice of Three-line Indica Hybrid Rice
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作者 游书梅 曹应江 +8 位作者 蒋开锋 郑家奎 吴先军 张涛 杨莉 杨乾华 万先齐 罗婧 李昭祥 《Agricultural Science & Technology》 CAS 2012年第11期2358-2362,共5页
Five cytoplasmic male sterile (CMS) lines were used as parents in an incomplete diallet cross and six restorer lines of rice design (Nc II design). Thirty hybrid combinations with the same growth period were selec... Five cytoplasmic male sterile (CMS) lines were used as parents in an incomplete diallet cross and six restorer lines of rice design (Nc II design). Thirty hybrid combinations with the same growth period were selected as experimental ma- terials to investigate the heterosis, combined ability and heredity of Cd content in brown rice of indica hybrid rice. According to the results, Cd content in brown rice showed a significantly negative heterosis; the general combining ability and specific combination ability of Cd content in CMS and restorer lines both reached extremely significant level (P〈0.01), indicating that both genetic improvement of parents and e- valuation of combinations are important to the breeding of hybrid combinations with low accumulation of Cd; the broad-sense heritabitity and narrow-sense heritability of Cd content were both relatively high with slight differences, which respectively reached 97.73% and 80.10%, indicating that Cd content in brown rice mainly de- pends on the additive action of genes; in addition, parent improvement showed bet- ter effect on the selection of early generation. 展开更多
关键词 Indica hybrid rice Brown rice Cytoplasmic male sterile (CMS) line Re-storer line Cadmium HETEROSIS Combining ability HERITABILITY
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Progress and future development of hybrid rapeseed in China 被引量:10
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作者 Fu Tingdong Zhou Yongming 《Engineering Sciences》 EI 2013年第5期13-18,共6页
The hybrid growth of rapeseed now has reached to 4.7×106hm2,accounting for 70 % of total rapeseed growth area in China. Over the last 40 years,the researches and utilizations of hybrid rapeseed in China have sign... The hybrid growth of rapeseed now has reached to 4.7×106hm2,accounting for 70 % of total rapeseed growth area in China. Over the last 40 years,the researches and utilizations of hybrid rapeseed in China have significantly contributed to the development of rapeseed industry in China. The production of hybrid rapeseed mainly utilizes cytoplasmic male sterility(CMS),combined at the same time with nuclear male sterility and other pollinating-control systems in China. The hybrid rapeseed studies in China are also characterized by the improvement of quality and oil content in hybrid breeding. Future studies to enhance the heterosis of rapeseed will be focused on several important issues,including the combination of heterosis and ideotype breeding,further increase of oil content in hybrids,utilization of sub-genomic heterosis and resistance improvement. The paper will discuss the following perspectives in hybrid rapeseed studies:relationships among heterosis,quality and disease traits,solutions for excessive source and pool in hybrids compared with open-pollinated cultivars,and the importance of increasing harvest index of hybrids to achieve a better yield in hybrids. 展开更多
关键词 oil crops RAPESEED HETEROSIS plant breeding
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载流子与铁磁物质耦合系统的严格对角化解与相干态变分方法 被引量:1
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作者 黄书文 刘涛 +1 位作者 范云霞 汪克林 《物理学报》 SCIE EI CAS CSCD 北大核心 2007年第1期491-499,共9页
引用Schwinger的角动量谐振子理论将载流子与铁磁物质耦合系统变换为载流子与两类玻色子耦合的问题,对铁磁物质中束缚极化子的存在决定于介质中有无杂质势的规律进行了严格对角化求解.得到的结论与普遍的看法一致,与相干态变分方法计算... 引用Schwinger的角动量谐振子理论将载流子与铁磁物质耦合系统变换为载流子与两类玻色子耦合的问题,对铁磁物质中束缚极化子的存在决定于介质中有无杂质势的规律进行了严格对角化求解.得到的结论与普遍的看法一致,与相干态变分方法计算的基态能结果十分吻合,两种方法得到的波矢定性上也吻合,说明了相干态变分方法的可靠性和有较高的准确性,严格对角化解方法也可为其他的近似方法提供检验基础. 展开更多
关键词 束缚极化子 杂质势 铁磁物质 严格对角化解
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二维磁极化子的研究 被引量:2
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作者 刘涛 张怀红 +1 位作者 冯芒 汪克林 《中国科学(G辑)》 CSCD 2006年第4期346-355,共10页
运用系统的变分和模拟退火数值计算,对二维反铁磁物质中自陷磁极化子和铁磁物质中束缚磁极化子进行了研究.通过运用Schwinger角动量理论将原问题变换为载流子与两类Boson的耦合问题,计算得到二维自陷磁极化子具有单峰和多峰结构.计算表... 运用系统的变分和模拟退火数值计算,对二维反铁磁物质中自陷磁极化子和铁磁物质中束缚磁极化子进行了研究.通过运用Schwinger角动量理论将原问题变换为载流子与两类Boson的耦合问题,计算得到二维自陷磁极化子具有单峰和多峰结构.计算表明,对于铁磁物质,二维束缚极化子的性质与一维情形基本一致,但对于反铁磁物质,二维自陷磁极化子的结构比一维情形要丰富得多. 展开更多
关键词 自陷极化子 束缚极化子 杂质势 反铁磁物质
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