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Hierarchical FeO_(χ)H_(y)@Ni_(3)B hybrid for efficient alkaline oxygen evolution at high current density
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作者 Fuxi Liu Qing Liang +5 位作者 Zhenyu Li Meiqi Liu Nailin Yue Zizhun Wang Xu Zou Wei Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期599-607,共9页
Electrocatalysts with high activity and long-term durability are vital toward large-scale hydrogen pro-duction from electrocatalytic water splitting.Here,the self-supported electrode(FeO_(χ)H_(y)@Ni_(3)B/NF)with hier... Electrocatalysts with high activity and long-term durability are vital toward large-scale hydrogen pro-duction from electrocatalytic water splitting.Here,the self-supported electrode(FeO_(χ)H_(y)@Ni_(3)B/NF)with hierarchical heterostructure was simply prepared by using Ni_(3)B chunks grown on nickel foam as sub-strate to in situ form vertical FeO_(χ)H_(y)nanosheets.Such hybrid shows efficient oxygen evolution reaction activity with overpotentials as low as 267 and 249 mV at 100 mA cm^(-2)in 1 M KOH solution and 30 wt%KOH solution,respectively.Meanwhile,it also exhibits excellent catalytic stability,sustaining catalysis at 500 mA cm^(-2)in 1 M KOH solution for 200 h,and even for 200 h at 1000 mA cm^(-2)in 30 wt%KOH solution.Further experimental results reveal that the FeO_(χ)H_(y)@Ni_(3)B/NF is endowed with superhydrophilic and superaerophobic surface properties,which not only provide more mass transport channels,as well as facilitated the diffusion of reaction intermediates and gas bubbles.Also,it holds faster reaction kinetics,more accessible active sites and accelerated electron transfer rates due to strong synergistic interactions attheheterogeneous interface. 展开更多
关键词 FeO_(χ)H_(y)@Ni_(3)B/NF hybrid Heterostructure Oxygen evolution reaction ELECTROCATALYTIC
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水稻不育系泰丰A创制及其优良品质性状遗传基础研究 被引量:2
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作者 王丰 刘迪林 +8 位作者 朱满山 廖亦龙 李金华 付崇允 曾学勤 马晓智 霍兴 孔乐 柳武革 《中国稻米》 北大核心 2024年第4期24-32,共9页
针对杂交稻“高产难优质”的瓶颈问题,基于杂种优势群与优势模式,选择华南地区高配合力、高异交率保持系博B和优质丝苗米亲本米31以及长江流域优质抗病早稻浙9248作为育种亲本进行复合杂交,通过穿梭种植生态加压表型鉴定与室内品质鉴定... 针对杂交稻“高产难优质”的瓶颈问题,基于杂种优势群与优势模式,选择华南地区高配合力、高异交率保持系博B和优质丝苗米亲本米31以及长江流域优质抗病早稻浙9248作为育种亲本进行复合杂交,通过穿梭种植生态加压表型鉴定与室内品质鉴定相结合的方法,育成了粒型细长、整精米率高、食味佳的“三高一优”不育系及其保持系泰丰A/B。截至2023年,用泰丰A配组育成泰丰优208、泰优390、泰优1002和泰优398等优质杂交稻共计92个。其中,80.4%的米质达到国(部)标优质3级以上标准,18个品次获得国家或省级优质稻食味鉴评金奖和银奖,2个品种被农业农村部认定为超级稻,较好解决了杂交稻“高产难优质”的“卡脖子”问题。此外,对控制泰丰A/B重要品质性状的QTLs(基因)进行了分析,发现位于第3、5、6和7号染色体上的gs3、GW5TFB、WxTFB和GW7TFB基因或其所在的染色体区段是泰丰A/B品质表现优异的重要遗传基础。 展开更多
关键词 杂交稻 不育系 保持系 泰丰A/B 稻米品质 遗传基础
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面向科技文献多维语义组织的混合倒排索引构建方法
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作者 张敏 李唯 范青 《现代情报》 CSSCI 北大核心 2024年第2期107-114,129,共9页
[目的/意义]为满足科研人员对科技文献内部细粒度语义信息进行高效查询的迫切需求,前期研究提出了面向科技文献的多维语义索引体系,然而基于HashMap的常见倒排索引会导致查询效率低下。本文旨在通过面向不同维度语义特征建立混合倒排索... [目的/意义]为满足科研人员对科技文献内部细粒度语义信息进行高效查询的迫切需求,前期研究提出了面向科技文献的多维语义索引体系,然而基于HashMap的常见倒排索引会导致查询效率低下。本文旨在通过面向不同维度语义特征建立混合倒排索引,以改进语义查询性能。[方法/过程]本文以Treap、B+树等多种数据结构探索适合不同语义维度的倒排索引构建方法,并将其组合形成多种适用于科技文献多维语义组织的混合倒排索引构建方法,并通过对比实验,在排序查询和布尔查询条件下分析验证不同类型倒排索引构建方法的查询性能。[结果/结论]实验结果表明,组合形成的8种混合倒排索引构建方法中,表2所示的C3(HHHB)被证明在排序查询条件下具有最高的效率,而C4(TTTB)则在布尔查询条件下被证明最为高效。本文的方法能有效解决单一索引结构导致的查询效率问题。 展开更多
关键词 科技文献 语义组织 混合倒排索引 HashMap Treap B+树
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Phytogenetic Studies on Intergeneric Hybridization Between Brassica napus and Matthiola incana 被引量:13
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作者 罗鹏 傅华龙 +3 位作者 蓝泽蘧 周颂东 周洪芳 罗晴 《Acta Botanica Sinica》 CSCD 2003年第4期432-436,共5页
The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of ra... The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of rape seed, ovaries of B. napus pollinated with pollen of M. incana, were cut off and inoculated onto MS media supplemented with various plant hormones at the 7th day after pollination. Two mature embryos were obtained from 750 pollinated ovaries cultured in vitro. The percentage of seed set was 0.26%. The mature embryos were transferred onto the MS media supplemented with 2.0 mg/L 6-BA + 0.1 mg/L NAA, and a compound bud was produced later. The compound bud was then cut into a number of single buds, which were transferred onto fresh media. Twenty-two plantlets in vitro were developed from the above single buds. The hybrid plants (F-1) were basically intermediate between the two parents in many,characters with a few showing hybrid vigor. The fertility of hybrid plants (F-1) was poor. Cytological studies revealed that the hybrid plants (F-1) were mixoploid. in nature. The chromosome number of many somatic cells was 2n = 26, which was the sum of the chromosome number of the two parents. The chromosome number of other somatic cells was 2n = 38, similar to that of B. napus. The hybrid offspring (F-2) from the selfed hybrid plants (F-1) showed polymorphism. Among the hybrid offspring (F-2) some were nearly matroclinous and fertile, similar to B. napus. some others were intermediate between the two parents and less fertile, and a few were poorly developed and nearly infertile. From the hybrid offspring a few plants with improved seed-oil quality were obtained. 展开更多
关键词 Brassica napus Matthiola incana intergeneric hybridization phytogenetic studies
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双低油菜湘油15(B.napus)对菌核病抗性的研究 被引量:16
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作者 官春云 李方球 +3 位作者 李栒 陈社员 王国槐 刘忠松 《作物学报》 CAS CSCD 北大核心 2003年第5期715-718,T003,共5页
经苗期菌丝块接种鉴定和花期带菌牙签鉴定表明 ,双低油菜湘油 15对菌核病有高抗性。当病原危害后 ,湘油15体内酚类物质含量和几丁质酶活性迅速升高 ,且维持时间长 ,湘油 15与感病品种 98C4 0和中抗品种中油 82 1杂交后代抗性表现为双亲... 经苗期菌丝块接种鉴定和花期带菌牙签鉴定表明 ,双低油菜湘油 15对菌核病有高抗性。当病原危害后 ,湘油15体内酚类物质含量和几丁质酶活性迅速升高 ,且维持时间长 ,湘油 15与感病品种 98C4 0和中抗品种中油 82 1杂交后代抗性表现为双亲平均值 。 展开更多
关键词 双低油菜 “湘油15” b.napus 菌核 病抗性 苗期 菌丝块 接种鉴定
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Analysis of Correlation between Yield and Quality Traits of Quality Hybrid Rapeseed 被引量:3
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作者 高志宏 赵继献 +1 位作者 任廷波 程国平 《Agricultural Science & Technology》 CAS 2013年第12期1737-1741,1771,共6页
[Objective] This study aimed to investigate the correlation between yield and quality traits of rape. [Method] Taking "Sanbei 98" and "Youyan 599" as ex- periment materials, correlation between yield and quality t... [Objective] This study aimed to investigate the correlation between yield and quality traits of rape. [Method] Taking "Sanbei 98" and "Youyan 599" as ex- periment materials, correlation between yield and quality traits of Brassica napus L. cultivars was explored by orthogonal rotation method. [Result] The results showed that: 1 In both the two varieties-Sanbei98 and Youyan599, erucic acid content had the largest coefficient of variation, but its average content was lower than 2% in both the two varieties (0.90% in Sanbei98 and 1.24% in Youyan599), and the palmitic acid content had the smallest coefficient of variation. 2 In terms of the dif- ferences in quality traits at different yield levels, only the mean of eicosenoic acid content revealed significant difference in Sanbei98, and only the mean of seed-pro- tein content revealed significant difference in Youyan599, and there was no signifi- cant difference in any combined quality traits in both the two varieties. 3 The yield was negatively correlated with the erucic acid content or oil content, and posi- tively correlated with the content of seed-protein, linoleic acid, or linolenic acid, and the coefficient of correlation between the yield and either of the contents of glucosi- nolates, oleic acid, palmitic acid, stearic acid, and eicosenoic acid was smaller. ~, when the yield of a variety increased considerably, there was a certain decreasing trend in erucic acid content, oil content, the total amount of erucic chain fatty acids (El & Er), while there was an increasing trend in seed-protein content, linoleic acid content, linolenic acid content, saturated fatty acids (SFA), the total amount of fat and protein (P & F), unsaturation index (IUFA), unsaturated fatty acids (UFA), the total amount of 18 carbon fatty acids (18-C FA), unsaturated fatty acids [UFA/(Ei & Er) ], and the sum of oleic acid and linoleic acid (OI & Li). 5 When the seed-pro- tein content is increased, the quality of rape oil cake is also improved; when the unsaturated index is increased, the oil stability is decreased. The increase in the total amount of unsaturated fatty acids, oleic acid and linoleic acid helps to increase in the total amount of fatty acids absorbed by human bodies. [Conclusion] This study provides a theoretical foundation for the cultivation of high-yielding and top- quality hybrid rape cultivars. 展开更多
关键词 Brassica napus L. rape cultivars Top-quality hybrid rape Quality traits YIELD Correlation analysis
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强冬性和春性甘蓝型油菜变种间杂种优势分析
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作者 王莹 郑国强 +5 位作者 董小云 李辉 魏家萍 崔俊美 武泽峰 刘自刚 《核农学报》 CAS CSCD 北大核心 2024年第5期833-841,共9页
为了研究甘蓝型强冬性与春性油菜变种间亲本组配的杂交组合之间的杂种优势表现,选用8个强冬性甘蓝型油菜和4个春性甘蓝型油菜作为研究材料,组配杂交组合,分析亲本及F1的杂种优势强/弱。结果表明,冬×春组合的F1生育期较冬性亲本明... 为了研究甘蓝型强冬性与春性油菜变种间亲本组配的杂交组合之间的杂种优势表现,选用8个强冬性甘蓝型油菜和4个春性甘蓝型油菜作为研究材料,组配杂交组合,分析亲本及F1的杂种优势强/弱。结果表明,冬×春组合的F1生育期较冬性亲本明显缩短;在冬×春组合中,株高、分枝部位、主花序长度、角果长度和单株有效角果数等方面有较强的杂种优势,其中角果长度(超亲优势:10.61%,杂种优势指数:128.81%)和单株有效角果数(超亲优势:17.31%,杂种优势指数:143.92%)杂种优势最为明显。结合杂种表现和杂种优势结果,说明甘蓝型油菜变种间杂交比种内杂交具有更明显的杂种优势表现,并且角果长度和单株有效角果数的超亲优势和杂种优势指数最高。本研究结果为今后研究甘蓝型油菜变种间杂种优势的研究利用提供了基础。 展开更多
关键词 甘蓝型油菜 杂种优势 变种间杂种 农艺性状
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Hybrid手术在复杂Stanford B型夹层中的临床应用 被引量:7
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作者 王贤灿 尚玉强 +4 位作者 李炳 易凡 戴仕林 吴伟 程龙 《转化医学杂志》 2018年第5期294-297,共4页
目的探讨Hybrid手术治疗累及主动脉弓部分支血管的Stanford B型主动脉夹层的临床效果及并发症。方法回顾分析2014年1月—2016年1月武汉市中心医院收治87例行Hybrid手术治疗复杂Stanford B型主动脉夹层的患者,观察其术后疗效及并发症发... 目的探讨Hybrid手术治疗累及主动脉弓部分支血管的Stanford B型主动脉夹层的临床效果及并发症。方法回顾分析2014年1月—2016年1月武汉市中心医院收治87例行Hybrid手术治疗复杂Stanford B型主动脉夹层的患者,观察其术后疗效及并发症发生情况。累及Z0区9例,行头臂干(brachiocephalic trunk,BCT)-左颈总动脉(left common carotid artery,LCCA)+BCT-左锁骨下动脉(left subclavian artery,LSA)+胸主动脉腔内修复术(thoracic endovascular aortic repair,TEVAR)术;累及Z1区23例,行BCT-LCCA-LSA+TEVAR术;累及Z2、3区55例,行LCCA-LSA+TEVAR术;颈部血管旁路选用8 mm Gore-Tex人工血管,TEVAR选用美敦力或先健覆膜血管支架。结果无病例死亡,术后即刻造影无病例内漏,61例术毕苏醒拔管,26例术后次日顺利脱机拔管;术后出现肾衰3例,脑梗1例;随访6~48个月,出现内漏1例,无截瘫发生,恢复良好。结论Hybrid手术治疗复杂Stanford B型主动脉夹层患者,具有微创、安全、有效的临床疗效,具有低风险、低并发症发生率的策略优势;根据患者的夹层解剖学范围以及患者的综合条件,选择个性化的Hybrid手术策略是手术成功的关键。 展开更多
关键词 hybrid手术 STANFORD B型主动脉夹层 颈部转流 主动脉腔内修复术
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Effect of Main Cultivation Factors on Oil Quality and Stability of Brassica napus Hybrids 被引量:1
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作者 赵继献 杜才富 +2 位作者 任廷波 程国平 王仙萍 《Agricultural Science & Technology》 CAS 2014年第5期795-800,共6页
[Objective] This study aimed to analyze the influence of five cultivation factors: sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount and potash fertilizer amount on oil quality and ... [Objective] This study aimed to analyze the influence of five cultivation factors: sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount and potash fertilizer amount on oil quality and stability of Brassica napus hybrids. [Method] Statistical analysis was carried out based on the data from previous studies and our work. [Result] Sowing date had no significant influence on oil quality and stability of B. napus hybrids. The plant density shared a positive correlation with 18-C fatty acid (FA) content, unsaturated fatty acid (UFA) content, total content of linoleic acid and linolenic acid, index of unsaturated fatty acid (IUFA), so a large plant density can improve the oil quality (by increasing18-C FA content, UFA content, total content of linoleic acid and linolenic acid), but reduce the oil stability (by increasing IUFA). The amount of nitrogen fertilizer had no significant influence on the contents of 18-C FA and UFA, but significant positive correlations with the total content of linoleic acid and linolenic acid and IUFA. So, the total content of linoleic acid and linolenic acid can be reduced by increasing nitrogen amount, meanwhile the oil stability was also decreased. Phosphate fertilizer amount did not affect 18-C FA significantly, but was negatively correlated with the UFA content, total content of linoleic acid and linolenic acid, and IUFA. So, increasing the amount of applied phosphate fertilizer can reduce UFA content, total content of linoleic acid and linolenic acid, thereby improving oil stability. Potash fertilizer had no significant influence on the IUFA, a significant positive correlation with 18-C FA content, an insignificant positive correlation with the the UFA content, and a negative correlation with the total content of linoleic acid and linolenic acid. The oil content of rapeseed shared an extremely significant positive correlation with 18-C FA content and UFA content, an negative correlation with the total content of linoleic acid and linolenic acid, and no significant correlation with IUFA. [Conclusion] This study identified the effects of five main cultivation factors on oil quality and stability of B. napus hybrids, and the correlations of oil content with 18-C FA content, UFA content, total content of linoleic acid and linolenic acid, and IUFA. 展开更多
关键词 Brassica napus hybrids Cultivation factors Oil quality Oil stability INFLUENCE
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Morphological and Cytogenetic Analysis on the Advanced Generations of Generic Hybrids between Brassica napus and Orychophragmus violaceu
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作者 赵志刚 杜德志 李再云 《Agricultural Science & Technology》 CAS 2012年第7期1410-1414,1446,共6页
[Objective] This study aimed to reveal the genetic changes of advanced generation hybrids between Brassica napus and Orychophragmus violaceus. [Method] The morphological characteristics such as the plant shape, branch... [Objective] This study aimed to reveal the genetic changes of advanced generation hybrids between Brassica napus and Orychophragmus violaceus. [Method] The morphological characteristics such as the plant shape, branching sites, leaf shape, leaf color, primary branches and secondary branches, as well as the cytological characteristics of the advanced generation hybrids (F8-F10) between B. napus and O. violaceus were observed. [Result] The morphology analysis revealed that the hybrid progeny was more like B. rapa in leaf shape, leaf color, plant shape and early flowering phenotype, whereas more like B. napus in number of secondary branches, silique length and 1 000-seed weight. Analysis on the cytogenetics characteristics showed that these advanced inbred progenies were hypoploids with less than 38 chromosomes; moreover, all the chromosomes from O. violaceus had been lost. Chromosome pairings at meiotic diakinesis of hybrids between the advanced inbred progenies and B. rapa revealed that chromosomes lost in hypoploids possibly belonged to the C genome of B. oleracea. With generations developing, chromosomes number of plants from two populations gradually increased and developed into the number of B. napus (2n=38). [Conclusion] This study will provide reference to reveal the source of chromosome lost in hypoploids and the morphological change of hybrids. 展开更多
关键词 BRASSICA NAPUS Orychophragmus VIOLACEUS Sexual hybridS Hypoploid
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五轴混联机构时间最优速度规划及精准插补
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作者 陈迪赛 高健 +1 位作者 罗于恒 张揽宇 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2024年第8期112-123,共12页
为提高五轴混联机构对复杂曲面及其特征的加工质量,提出一种准确识别曲率点的时间最优速度规划及精准插补方法。首先,采用向心法生成路径节点参数,作密集化处理生成速度节点参数;其次,用B样条描述速度曲线,通过伪加加速度将三阶约束模... 为提高五轴混联机构对复杂曲面及其特征的加工质量,提出一种准确识别曲率点的时间最优速度规划及精准插补方法。首先,采用向心法生成路径节点参数,作密集化处理生成速度节点参数;其次,用B样条描述速度曲线,通过伪加加速度将三阶约束模型转变为线性模型;然后,以速度节点参数为分段点,构造各段路径的时间积分函数,采用自适应辛普森积分法求解;最后,将所得离散点信息输入到运动控制卡进行轨迹加工。实验结果表明:本方法可快速收敛到全局最优,降低曲率点速度并迅速回升其邻域速度;计算所得路径总时间仅有3.5μs的波动,与常规插补方法收敛后的精度一致,且收敛时间更短;位置和角度的最大插补误差分别为0.76×10^(-3) mm和0.9×10^(-3)°,小于编码器分辨率,符合加工需求,特别是极大曲率处相比一般方法降低95.37%。因此,在路径曲线基础上生成的速度节点参数具备更好的曲率识别性,通过构造各段路径的时间积分函数求解路径总时间具备更高的鲁棒性与效率。 展开更多
关键词 五轴混联机构 时间最优速度规划 曲率 B样条 插补
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Comparions of Required Nitrogen Fertilizers by Hybrid Cultivar and Conventional Cultivar of Rapeseed(Brassica napus L.)
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作者 李银水 余常兵 +4 位作者 谢立华 胡小加 秦璐 廖祥生 廖星 《Agricultural Science & Technology》 CAS 2015年第10期2231-2237,共7页
[Objective] The aim of this study was to understand the difference of N fertilizer requirement between hybrid rapeseed and conventional rapeseed. [Method] Two hybrid cultivars, ZY5628 and ZY7819, and the conventional ... [Objective] The aim of this study was to understand the difference of N fertilizer requirement between hybrid rapeseed and conventional rapeseed. [Method] Two hybrid cultivars, ZY5628 and ZY7819, and the conventional cultivar ZS10, were compared through two field experiments. In Experiment 1, seed yield and optimum N application rate were assessed in the field with five N application treatments. In Expedment 2, N was applied uniformly at 180 kg/hm2, and plant biomass and N accumulation were measured at several developmental stages, while N use efficien- cy was calculated for rape at maturity. [Results] The experiment 1 results showed that seed yields of ZY5628 and ZY7819 were both significantly higher than that of ZS10, and compared to ZS10, optimum yield (plateau yield) was higher by 18.7% and 20.2%, while the recommended N application rate was lower by 9.5% and 9.6% for ZY5628 and ZY7819, respectively. The experiment 2 results showed that during vegetative development, all three cultivars exhibited similar accumulations of plant biomass and N, but through flowering and maturity ZY5628 and ZY7819 pro- duced more biomass, acquired more N, and utilized acquired N more efficiently to- wards seed production than ZS10. [Conclusion] With equivalent inputs, the hybrid rapeseed cultivars ZY5628 and ZY7819 tested herein yield more seed with higher N use efficiency than the conventional rapeseed ZS10. This information will be valu- able for growers seeking to improve efficiency while reducing costs of rape production in China. 展开更多
关键词 Rapeseed (Brassica napus. L) hybrid cultivars Yield Nitrogen applica- tion rate Nitrogen use efficiency
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FISH信号类型和染色体核型分析在ETV6/RUNX1阳性B-ALL患儿中的诊疗价值评估
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作者 高雨晴 徐鸥 胡绍燕 《临床与实验病理学杂志》 CAS 北大核心 2024年第1期40-43,共4页
目的探讨FISH信号类型和染色体核型分析对ETV6/RUNX1阳性B系急性淋巴细胞白血病(B-acute lymphoblastic leukemia,B-ALL)的诊疗价值。方法收集164例ETV6-RUNX1融合阳性B-ALL患者的临床病理资料,对其染色体核型和FISH的结果进行回顾性分... 目的探讨FISH信号类型和染色体核型分析对ETV6/RUNX1阳性B系急性淋巴细胞白血病(B-acute lymphoblastic leukemia,B-ALL)的诊疗价值。方法收集164例ETV6-RUNX1融合阳性B-ALL患者的临床病理资料,对其染色体核型和FISH的结果进行回顾性分析。结果164例患者中FISH检出163例阳性,其中61例为经典阳性信号2F1R1G;102例为非经典信号,其中2F1G和1F1R2G信号类型最多,提示ETV6缺失;164例患者中有8例患儿未做染色体核型分析,31例患儿因无核分裂象未能进行染色体核型分析,可以进行核型分析的125例患儿中,正常核型106例,异常核型19例,且均未检出t(12;21)易位。结论FISH技术检测ETV6/RUNX1融合基因敏感度高,且多表现为包括ETV6缺失在内的非经典信号类型;染色体核型分析有助于发现复杂核型和超倍体,但不利于t(12;21)融合的检出。因此FISH信号类型和染色体核型分析在ETV6/RUNX1阳性B-ALL中具有不可或缺的作用。 展开更多
关键词 儿童B淋巴细胞白血病 染色体核型分析 荧光原位杂交 ETV6/RUNX1融合基因
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硼氮共掺杂海藻酸钠基多孔炭及其快速高效储锌
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作者 卢亚平 王红星 +2 位作者 刘澜涛 庞伟伟 陈晓红 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第3期506-514,共9页
近年来,锌离子电容器(ZIHCs)因其环境友好性和优异的电化学性能而备受关注。然而,ZIHCs的研究体系尚不成熟,为改善ZIHCs的储能动力学和循环稳定性等问题,亟需研发出低成本和高性能的碳基电极材料。本工作以海藻酸钠为碳前驱体,五硼酸铵... 近年来,锌离子电容器(ZIHCs)因其环境友好性和优异的电化学性能而备受关注。然而,ZIHCs的研究体系尚不成熟,为改善ZIHCs的储能动力学和循环稳定性等问题,亟需研发出低成本和高性能的碳基电极材料。本工作以海藻酸钠为碳前驱体,五硼酸铵为氮源和硼源,采用一步水热活化策略合成了氮/硼含量较高的分级多孔炭(NBSPC)。这种策略可以有效重塑炭的多孔结构,产生大量的活性位点,贡献额外的赝电容,从而提高其电化学性能。以NBSPC为正极构建了锌离子电容器,其在40 A g^(-1)的超高电流密度下,可以实现85.4 mAh g^(-1)优异的倍率性能,并在10 A g^(-1)的电流密度下可以稳定循环15000次,容量保持率高达94.5%。 展开更多
关键词 海藻酸钠衍生多孔炭 氮/硼共掺杂 一步水热活化 锌离子电容器
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一种混合仿生机械手轨迹规划优化方法研究
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作者 刘军 吴鹏涛 《机械设计与制造》 北大核心 2024年第5期199-207,213,共10页
针对某串并联混合仿人机器人机械手,提出了多目标机械手最优轨迹的优化方法。首先采用归一化雅可比条件数作为静态指标,得到关节速率分布的路径,在获得轨迹规划所需的路径后,通过建立五次B样条插值轨迹进行规划,采用NSGA-II程序对轨迹... 针对某串并联混合仿人机器人机械手,提出了多目标机械手最优轨迹的优化方法。首先采用归一化雅可比条件数作为静态指标,得到关节速率分布的路径,在获得轨迹规划所需的路径后,通过建立五次B样条插值轨迹进行规划,采用NSGA-II程序对轨迹进行优化,通过定义目标的权值来确定最优解,包括行程时间、能量消耗和力矩波动。在此基础上采用牛顿-欧拉法的平衡方程和小变形叠加原理的变形协调方程组合得到混合仿生机器人的动态全解。最后通过ADAMS仿真验证了混合仿生机器人动力学模型的正确性。 展开更多
关键词 混合仿生机械手 轨迹优化 雅可比条件 B样条插值
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Carbon Nanotube-hybridized Supramolecular Hydrogel Based on PEG-b-PDMAEMA/α-cyclodextrin
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作者 吴智明 吴文文 +1 位作者 李玉金 赵昕 《科技信息》 2011年第5期I0168-I0168,I0419,共2页
Well-dispersed multi-walled cabon nanotubes(MWCNTs) were successfully incorporated into a supramolecular hydrogel through combining dual roles of poly(ethylene glycol)-block-poly[(2-dimethylamino) ethyl methacrylate](... Well-dispersed multi-walled cabon nanotubes(MWCNTs) were successfully incorporated into a supramolecular hydrogel through combining dual roles of poly(ethylene glycol)-block-poly[(2-dimethylamino) ethyl methacrylate](PEG-b-PDMAEMA) copolymer in dispersing MWCNTs and forming inclusion complexes with α-cyclodextrin(α-CD).Rheological behaviors of supramolecular hydrogels were investigated.The resultant hybrid hydrogels were found to be shear thinning and could be applied as a promising injectable drug delivery system.The mechanical strength of the hybrid hydrogels was greatly improved in comparison with that of the corresponding native hydrogels. 展开更多
关键词 碳纳米管 超分子水凝胶 药物输送系统 机械强度
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Abortive Process of a Novel Rapeseed Cytoplasmic Male Sterility Line Derived from Somatic Hybrids Between Brassica napus and Sinapis alba 被引量:5
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作者 WANG Juan GAO Ya-nan +4 位作者 KONG Yue-qin JIANG Jin-jin LI Ai-min ZHANG Yong-tai WANG You-ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第4期741-748,共8页
Somatic hybridization is performed to obtain significant cytoplasmic male sterility (CMS) lines, whose CMS genes are derived either from the transfer of sterile genes from the mitochondrial genome of donor parent to... Somatic hybridization is performed to obtain significant cytoplasmic male sterility (CMS) lines, whose CMS genes are derived either from the transfer of sterile genes from the mitochondrial genome of donor parent to the counterpart of receptor or production of new sterile genes caused by mitochondrial genome recombination of the biparent during protoplast fusion. In this study, a novel male sterile line, SaNa-IA, was obtained from the somatic hybridization between Brassica napus and Sinapis alba. The normal anther development of the maintainer line, SaNa-IB, and the abortive process of SaNa-IA were described through phenotypic observations and microtome sections. The floral organ of the sterile line SaNa-IA was sterile with a shortened filament and deflated anther. No detectable pollen grains were found on the surface of the sterile anthers. Semi-thin sections indicated that SaNa-IA aborted in the pollen mother cell (PMC) stage when vacuolization of the tapetum and PMCs began. The tapetum radically elongated and became highly vacuolated, occupying the entire locule together with the vacuolated microspores. Therefore, SaNa-IA is different from other CMS lines, such as ogu CMS, pol CMS and nap CMS as shown by the abortive process of the anther. 展开更多
关键词 Brassica napus anther abortion cytoplasmic male sterility (CMS) semi-thin sections somatic hybridization
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Relationship Between Hybrid Performance and Genetic Diversity Based on SSRs and ISSRs in Brassica napus L. 被引量:3
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作者 FUTing-dong YANGGuang-sheng SHENJin-xiong 《Agricultural Sciences in China》 CAS CSCD 2003年第10期1083-1090,共8页
To investigate the relationship between genetic distance (GD) and hybrid performance, two types of molecular markers, microsatellites (simple sequence repeats, SSRs) and intro-simple sequence repeats (ISSRs), were emp... To investigate the relationship between genetic distance (GD) and hybrid performance, two types of molecular markers, microsatellites (simple sequence repeats, SSRs) and intro-simple sequence repeats (ISSRs), were employed to detect the genetic diversity of 3 double low self-incompatible lines and 22 male parental varieties of Brassica napus from different geographical origins. Hybrids were produced in a NCⅡ mating design by hand-pollination. The result indicated that 25 parental varieties (lines) could be divided into six groups by Un-weighted Pair Group Mathematics Average (UPGMA) clustering based on GDs. SI-1300 and SI-1320 could be singly clustered into one group, respectively. Varieties from China could be separated into another group, SI-1310 and varieties from foreign countries could be separated into other three groups. The grouping was generally consistent with parental pedigrees and geographical origins. Significant differences in yield, quality and phenological period traits were observed among these parent groups. Although hybrid yield/plant showed significantly positive correlation with genetic distance based on SSR and ISSR markers, but the determination coefficient was low. It appeared to be unsuitable for using the genetic distance based on SSR and ISSR markers to predict heterosis and hybrid performance in Brassica napus. 展开更多
关键词 Brassica napus L. Genetic diversity hybrid performance SSR ISSR
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Genome-wide prediction for hybrids between parents with distinguished difference on exotic introgressions in Brassica napus 被引量:3
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作者 Dandan Hu Yusheng Zhao +7 位作者 Jinxiong Shen Xiangxiang He Yikai Zhang Yong Jiang Rod Snowdon Jinling Meng Jochen C.Reif Jun Zou 《The Crop Journal》 SCIE CSCD 2021年第5期1169-1178,共10页
Extensive exotic introgression could significantly enlarge the genetic distance of hybrid parental populations to promote strong heterosis.The goal of this study was to investigate whether genome-wide prediction can s... Extensive exotic introgression could significantly enlarge the genetic distance of hybrid parental populations to promote strong heterosis.The goal of this study was to investigate whether genome-wide prediction can support pre-breeding in populations with exotic introgressions.We evaluated seed yield,seed yield related traits and seed quality traits of 363 hybrids of Brassica napus (AACC) derived from two parental populations divergent on massive exotic introgression of related species in three environments.The hybrids presented strong heterosis on seed yield,which was much higher than other investigated traits.Five genomic best linear unbiased prediction models considering the exotic introgression and different marker effects (additive,dominance,and epistatic effects) were constructed to test the prediction ability for different traits of the hybrids.The analysis showed that the trait complexity,exotic introgression,genetic relationship between the training set and testing set,training set size,and environments affected the prediction ability.The models with best prediction ability for different traits varied.However,relatively high prediction ability (e.g.,0.728 for seed yield) was also observed when the simplest models were used,excluding the effects of the special exotic introgression and epistasis effect by5-fold cross validation,which would simplify the prediction for the trait with complex architecture for hybrids with exotic introgression.The results provide novel insights and strategies for genome-wide prediction of hybrids between genetically distinct parent groups with exotic introgressions. 展开更多
关键词 hybrid Genome-wide prediction Exotic introgression Brassica napus HETEROSIS
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Evaluation on Genetic Diversity of Hybrid Parents Developed in Brassic napus 被引量:1
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作者 LIU Ping wu, ZHOU Guo ling, YANG Guang sheng and FU Ting dong (National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University/ Research Center of National Rapeseed Improvement, Wuhan 430070, P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2003年第9期1054-1060,共7页
Genetic diversity of 50 Brassic napus varieties including 21 sterile lines, 16 restorer lines and 13 check cultivars was estimated by SSR and ISSR. The UPGMA results showed that 50 Brassica napus varieties wer... Genetic diversity of 50 Brassic napus varieties including 21 sterile lines, 16 restorer lines and 13 check cultivars was estimated by SSR and ISSR. The UPGMA results showed that 50 Brassica napus varieties were divided into 4 groups. The restorer lines tested were classified into groupsⅠⅢ respectively. The sterile lines tested were classified into groupⅣ. In addition, the sterile lines could be further divided into two subgroups: except 1471AB, all genic male sterile lines were in subgroupⅠ, 1471AB and all cytoplasmic male sterile lines were in the subgroupⅡ. The UPGMA results also indicated that the restorer lines had more genetic diversity than the sterile lines. 展开更多
关键词 Brassic napus hybrid parents Genetic diversity SSR ISSR
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