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P-wave Ω_(b) states:masses and pole residues

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Chinese Physics C 2022年第4期46卷 23-33页

作者： yong-Jiang Xu yong-lu liu Ming-Qiu Huang Department of Physics College of Liberal Arts and SciencesNational University of Defense TechnologyChangsha 410073China

In this study,we consider all P-wave Ω_(b) states represented by interpolating currents with a derivative and calculate the corresponding masses and pole residues using the QCD sum rule *** of the large uncertainties in our calculation compared with the small difference in the masses of the excited Ω_(b) states observed by the LHCb collaboration,it is necessary to study other properties of the P-wave Ω_(b) states represented by the interpolating currents investigated in the present work to gain a better understanding of the four excited Ω_(b) states observed by the LHCb collaboration.

关键词： excited baryon state mass QCD sum rule

Small World Effects in a Harmonious Unifying Hybrid Preferential Model Networks

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Communications in Theoretical Physics 2007年第2X期48卷 377-383页

作者： FANG Jin-Qing BI Qiao LI yong lu Xin-Biao liu Qiang China Institute of Atomic Energy P.O. Box 275-81 Beijing 102413 China

Small worm effects in the harmonious unifying hybrid preferential model （HUHPM） networks are studied both numerically and analytically. The idea and method of the HUHPM is applied to three typical examples of unweighted BA model, weighted BBV model, and the TDE rnodel, so-called HUHPM-BA, HUHPM-BBV and HUHPM- TDE networks. Comparing the HUHPM with current typical models above, it is found that the HUHPM networks has the smallest average path length and the biggest average clustering coefficient. The results demonstrate that the HUHPM is more suitable not only for the un-iveighted models but also for the weighted models.

关键词： harmonious unifying hybrid preferential model small world effect network science

Cytological Behavior of Hybridization Barriers Between Oryza sativa and Oryza officinalis

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Agricultural Sciences in China 2011年第10期10卷 1489-1500页

作者： FU Xue-lin lu yong-gen liu Xiang-dong LI Jin-quan ZHAO Xing-juan Key Laboratory of Plant Molecular Breeding Guangdong Province/College of Agriculture South China Agricultural University Guangzhou510642 P.R. China

Oryza officinalis is one of the important wild species in the tertiary gene pool of Oryza sativa. It has a number of elite genes for rice breeding in resistance or tolerance. However, breeding barriers are so serious that the gene transfer is much difficult by sexual cross method between O. sativa and O. officinalis. Characteristics of the breeding barriers were systemically studied in this paper. When both the diploid （AA, 2n=2x=24） and autotetraploid （AAAA, 2n=4x=48） cultivated rice were crossed as maternal parents with O. officinalis （CC, 2n=2x=24）, none F1 hybrid seeds were obtained. The young hybrid ovaries aborted at 13-16 d after pollinations （DAP）. By rescuing hybrid embryos, in vitro F1 plantlets were obtained in 2x×2x combinations with the crossabilities lower than 0.5%. Lower rates of double-fertilization and abnormal development of hybrid embryo and endosperm were mainly observed in both combinations of 2x×2x and 4x×2x. Free endosperm nuclei in hybrid degenerated early at 1 DAP in a large scale. Almost no normal endosperm cells formed at 3 DAP. Development of a lot of embryos ceased at globularor pear-shaped stage as well as some degenerated gradually. The hybrid plantlets were both male and female sterility. Due to the abnormal development, a diversity of abnormal embryo sacs formed in hybrids, and hybrid pollen grains were typically abortive. It showed that conflicts of genome A and C in hybrid induced abnormal meioses of meiocytes.

关键词： breeding barriers interspecific hybridization crossability hybrid sterility Oryza sativa Oryza officinalis

Detection of Distorted Segregation in Genotype of Pollen Calli Derived from Hybrid F_1 of Cultivated Rice (Oryza sativa L.) Using SSR Markers

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Agricultural Sciences in China 2006年第6期5卷 412-416页

作者： YAO Yan lu yong-gen liu Xiang-dong FENG Jiu-huan ZHANG Gui-quan Guangdong Provincial Key Laboratory of Plant Molecular Breeding South China Agricultural University Guangzhou 510642 P.R.China

S-a, S-b and S-c are three loci for F1 pollen sterility in cultivated rice （Oryza sativa L.）. Taichung 65 （T65） is all Sj/Sj at these three loci, while its F1 pollen sterile near-isogenic lines, TISL2 （S-b）, TISL4 （S-a） and TISL5 （S-c） is Sj/Sj according to their respective sterility locus. Using SSR molecular marker to detect the segregation of the allele Si and Sj in pollen calli population induced from different hybrid F1, which have different pollen sterility locus, showed that the segregation of allele Si and Sj was distorted. The distorted direction of pollen calli population in vitro was not the same as F2 population in vivo. The quantities of pollen callus carrying Sj were much more than that of carrying Siat S-a and S-c locus, the ratio of Si and Sj were 1：4.81 and 1：1.96 respectively. But the opposite tendency was observed at S-b locus, the ratio of Si and Sj being 1：0.35. At the same time, all these results were undisturbed by either culture medium or culture period.

关键词： rice (Oryza sativa L.) pollen sterility pollen callus distorted segregation SSR marker

The Effect of CaAl2O4 Spinel on Ni/Al2O3 Catalyst for CH4/O2-to-Syngas Reaction

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分子催化 1997年第3期 6-7页

作者： lu yong liu Yu SHEN Shikong (Lanzhou Institute of Chemical Physics The Chinese Academy of Sciences Lanzhou 730000)

ＴｈｅＥｆｅｃｔｏｆＣａＡｌ２Ｏ４ＳｐｉｎｅｌｏｎＮｉ／Ａｌ２Ｏ３ＣａｔａｌｙｓｔｆｏｒＣＨ４／Ｏ２－ｔｏ－ＳｙｎｇａｓＲｅａｃｔｉｏｎ１）ＬＵＹｏｎｇＬＩＵＹｕＳＨＥＮＳｈｉｋｏｎｇ（ＬａｎｚｈｏｕＩｎｓｔｉｔｕｔ... 详细信息

ＴｈｅＥｆｅｃｔｏｆＣａＡｌ２Ｏ４ＳｐｉｎｅｌｏｎＮｉ／Ａｌ２Ｏ３ＣａｔａｌｙｓｔｆｏｒＣＨ４／Ｏ２－ｔｏ－ＳｙｎｇａｓＲｅａｃｔｉｏｎ１）ＬＵＹｏｎｇＬＩＵＹｕＳＨＥＮＳｈｉｋｏｎｇ（ＬａｎｚｈｏｕＩｎｓｔｉｔｕｔｅｏｆＣｈｅｍｉｃａｌＰｈｙｓｉｃ...

关键词： Methane Partial oxidation Syngas CaAl 2O 4 spinel Ni catalyst

Progress on Transferring Elite Genes from Non-AA Genome Wild Rice into Oryza sativa through Interspecific Hybridization

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Rice science 2008年第2期15卷 79-87页

作者： Fu Xue-lin lu yong-gen liu Xiang-dong LI Jin-quan Guangdong Provincial Key Laboratory of Plant Molecular Breeding South China Agricultural University Guangzhou 510642 China

The progress of research on transferring elite genes from non-AA genome wild rice into Oryza sativa through interspecific hybridization are in three respects, that is, breeding monosomic alien addition lines （MAALs）, constructing introgression lines （ILs） and analyzing the heredity of the characters and mapping the related genes. There are serious reproductive barriers, mainly incrossability and hybrid sterility, in the interspecific hybridization of O. sativa with non-AA genome wild rice. These are the ＇bottleneck＇ for transferring elite genes from wild rice to O. sativa. Combining traditional crossing method with biotechnique is a reliable way to overcome the reproductive barriers and to improve the utilizing efficiency of non-AA genome wild rice.

关键词： Oryza sativa non-AA genome wild rice interspecific hybridization monosomic alien addition line introgression line reproductive barrier gene mapping

Comparative Embryological Studies on Infertility of Interspecific Hybridizations Between Oryza sativa with Different Ploidy Levels and O. officinalis

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Rice science 2009年第1期16卷 58-64页

作者： FU Xue-lin lu yong-gen liu Xiang-dong LI Jin-quan ZHAO Xing-juan Guangdong Provincial Key Laboratory of Plant Molecular Breeding South China Agricultural University Guangzhou 510642 China

As maternal parents, diploid （L202-2x） and autotetraploid （L202-4x） of Oryza sativa cv. L2O2 were crossed with O. officinalis. Embryo development and fertilization in these two crosses were comparatively studied. There were no mature hybrid seeds obtained because all the hybridized spikelets died 30 days after pollination. The main reasons for no seed set were abnormal fertilization and development of the embryos and endosperms in the interspecific hybrids. There were doublefertilization, egg cell single-fertilization and non-fertilization in these crosses. Although 59.45% and 54.87% of hybrid embryos produced in the crosses of L202-2x/O. officinalis and L202-4x/O. officinalis, respectively, hybrid embryos ceased to develop or degenerated and plenty of free endosperm nuclei were in disaggregating state without developing cellular endosperms three days after pollination. Besides, some embryological differences in these two crosses were found, that is, the rate of double-fertilization and total rate of doubleand single-fertilization in L202-2x/O. officinalis were higher than those in L202-4x/O. officinalis. The embryo and endosperm of hybrids developed more slowly, and embryos and free endosperm nuclei were more severely degenerated in L202-4x/O. officinalis than in L202-2x/O. officinalis. Five days after pollination, a few of embryos in L202-2x/O. officinalis developed into pear-shaped ones, however, embryos in L202-4x/O. officinalis were all degenerated. Therefore, it is more difficult to obtain interspecific hybrids by wide crosses between autotetraploid of O. sativa and O. officinalis.

关键词： Oryza sativa Oryza officinalis diploid rice autotetraploid rice wild rice interspecific hybridization embryo development infertility

Abnormal Structure of Embryo Sac in Autotetraploid Rice

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Rice science 2006年第4期13卷 257-264页

作者： Guo Hai-bin FENG Jiu-huan lu yong-gen liu Xiang-dong Guangdong Provincial Key Laboratory of Plant Molecular Breeding South China Agricultural University Guangzhou 510642 China

The structures of mature embryo sacs in 13 genetic stock lines of autotetraploid rice （Oryza sativa L.）, including indica, japonica and javanica, were studied by using the whole-mount stain-clearing laser scanning confocal microscopy （WCLSM）. Among the 13 autotetraploid rice, the majority of ovaries possess normal polygonum-type embryo sacs, while a few ovaries were characterized by abnormal embryo sacs. The abnormalities of embryo sacs could be classified into six categories, i. e. no female germ unit, abnormal polar nuclei, embryo sac degeneration, no egg apparatus, small embryo sac and ＇double set＇ of embryo sacs. The frequency of abnormal embryo sac in japonica （26.6%） was higher than that in indica （19.34%）. In addition, the major abnormalities in each autotetraploid line varied, suggesting that the abnormalities may be related to the genotypes of the varieties.

关键词： autotetraploid rice structure anatomy embryo sac seed setting rate

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地铁车厢内乘客站立位置选择行为研究

交通运输系统工程与信息 2017年第2期17卷 142-147,159页

作者：史芮嘉毛保华丁勇刘路北京交通大学城市交通复杂系统理论与技术教育部重点实验室北京100044 扬州大学建筑科学与工程学院江苏扬州225127

基于地铁乘客在车厢内站立位置选择行为设计问卷并调查,引入信效度分析判断问卷及其结果的可靠性,分析乘客在车厢内站立位置的选择偏好和对座位的需求程度.针对乘客从车厢两端和车厢中部车门上车两种情景,将车厢内部站立区域划分为6部分... 详细信息

基于地铁乘客在车厢内站立位置选择行为设计问卷并调查,引入信效度分析判断问卷及其结果的可靠性,分析乘客在车厢内站立位置的选择偏好和对座位的需求程度.针对乘客从车厢两端和车厢中部车门上车两种情景,将车厢内部站立区域划分为6部分,建立考虑乘客出行距离和车厢内立席密度的乘客站立位置选择基线—类别Logit模型,采用调查数据对模型参数进行估计并验证.研究表明,模型标定结果与调查数据较为吻合,可较好地刻画乘客的选择行为.此外,乘客对车门前区的选择概率随车厢内立席密度的增大而增大,而坐席区域和侧边区域则相反;乘客出行距离较长时,乘客选择坐席区域的概率对车厢内立席密度的变化更为敏感.

关键词：城市交通地铁车厢 Logit模型乘客选择行为站立位置