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“南”、“北”为什么可与东、西“通”? 被引量:2
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作者 阿尔丁夫 《内蒙古大学学报(哲学社会科学版)》 2015年第1期34-38,共5页
清人顾祖禹在回答阎若璩提出的有关历史地理的问题时说:"凡地理,言‘南’可与东通,言‘北’可与西通……余自是触处洞然。"可是"南"、"北"为什么可与东、西相通呢?阎若璩没有进一步问,即便问,估计顾祖禹... 清人顾祖禹在回答阎若璩提出的有关历史地理的问题时说:"凡地理,言‘南’可与东通,言‘北’可与西通……余自是触处洞然。"可是"南"、"北"为什么可与东、西相通呢?阎若璩没有进一步问,即便问,估计顾祖禹也不一定能回答上来。何新先生试图回答这个问题,但也不得要领。其实,北半球回归线以北的人类主要族群都曾使用过一种依照面对日出方向朝阳者的体位确定四方的方式及其确定的A、B两种类型四方概念。其中,B种类型四方概念恰好以"南"(即今之东)为四方之首,连称则为"南"(=东)、"西"(=南)、"北"(=西)、"东"(=北),故"南"、"北"可与东、西通。 展开更多
关键词 依照面向日出方向朝阳者 体位 确定四方方式 B种类型 ”(=东) “西”(=) “北”(=西) “东”(=北)
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20世纪以来湘西南汉语方言研究述评 被引量:3
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作者 胡萍 《中南林业科技大学学报(社会科学版)》 2007年第4期67-70,共4页
湘西南20世纪以来在汉语方言研究方面取得了不少成果,但湘西南仍是湖南汉语方言研究的薄弱地带,无论在田野调查的力度上还是研究内容和领域的广度上都亟待加强和拓展。
关键词 西汉语方言 述评
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Boehmeria nivea var. strigosa (Urticaceae), a new variety from Southwest China 被引量:1
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作者 ZHAO Ying Richard I.MILNE +2 位作者 LI Zhipeng Amos KIPKOECH WU Zengyuan 《广西植物》 CAS CSCD 北大核心 2024年第9期1617-1624,I0001-I0006,共14页
Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly charact... Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly characterized by its green abaxial leaf blade,partly connate stipules,and densely patent strigose hairs on stems and potioles.The phylogenetic analysis based on rbc L,nrDNA and rbc L+nrDNA datasets,revealed that all individuals of B.nivea var.strigosa formed a monophyletic group.The conservation status of B.nivea var.strigosa is assessed as“Near Threatened”(NT)according to IUCN evaluation criteria.The discovery of this new variety is not only crucial for the taxonomy of ramie,but also provides reference for the exploration and utilization of ramie. 展开更多
关键词 Boehmeria nivea MORPHOLOGY molecular phylogeny new variety Southwest China YUNNAN
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Preparation of Total DNA from "Recalcitrant Plant Taxa 被引量:34
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作者 曾杰 邹喻苹 +1 位作者 白嘉雨 郑海水 《Acta Botanica Sinica》 CSCD 2002年第6期694-697,共4页
Contamination problems on DNA isolation from 'recalcitrant plant taxa' which is rich in polysaccharides have been commonly encountered in a wide range of research fields such as plant population biology, biodi... Contamination problems on DNA isolation from 'recalcitrant plant taxa' which is rich in polysaccharides have been commonly encountered in a wide range of research fields such as plant population biology, biodiversity, and molecular marker-assisted breeding. Here we present an improved protocol to extract DNA efficiently from dry or fresh leaves of a 'recalcitrant plant taxa', Betula alnoides Buch. Ham. ex D. Don in which three key steps are involved: 1) washing out most of polysaccharides and other secondary compounds with CTAB-free buffer from homogenate; 2) adoption of 3% CTAB rather than 2% CTAB in the exaction medium; and 3) using of high concentration of salt prior to DNA precipitation with isopropanol to remove residual polysaccharides. The isolated DNA has been proved suitable for RAPD-PCR amplification and restriction digestion. This modified procedure is simple, inexpensive and reliable, and is also applicable to many other plant taxa with high polysaccharides. 展开更多
关键词 Betula alnoides POLYSACCHARIDE DNA preparation RAPD restriction digestion
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Study on Urban Construction Land Suitability Evaluation in Southwestern Mountainous Areas of Yunnan Province Based on the Strategy of "Protecting Farmland in Flatland Areas and Constructing Mountainous Cities" : A Case in Lianghe County 被引量:4
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作者 贺一梅 杨子生 +2 位作者 张博胜 邓有旺 张德省 《Agricultural Science & Technology》 CAS 2014年第10期1774-1777,1780,共5页
According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat ... According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat area. Then this study deter- mined single evaluation factors index and comprehensive suitability index using "ex- treme conditions method" and "suitability index method", and analyzed and assessed the constructive land suitability on each evaluation unit polygons and its suitability level by using GIS software. Taking Lianghe County of Dehong Dai-Jingpo Au- tonomous Prefecture as an example to evaluate land suitability in Lianghe County's main towns around the gentle slope, the results show, in the evaluation area, the area of land suitable for construction and unsuitable for construction respectively ac- count 73.58% and 26.42%. And first-class, second and third-class of land suitable for construction should be composited at the ratio of about 11:49:40. The suitability evaluation index system and method developed in this paper is applicable for evalu- ating the construction land suitability in mountainous areas of southwest Yunnan Province, and will provide theoretical and technical support for land policy measures which strengthen the protection of farmland and promote the scientific development of urbanization in Yunnan Province and even similar mountainous areas of the whole China. 展开更多
关键词 Mountainous area Constructive land Suitability evaluation Comprehensive suitability index Southwestern Yunnan Province
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Discussion Abiotic Stress Tolerance and Corresponding Strategies for Maize Breeding in Southwest Region of China 被引量:1
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作者 汤玲 袁亮 +4 位作者 杨华 张亚勤 周汝平 赖军 邱正高 《Agricultural Science & Technology》 CAS 2017年第11期2037-2044,共8页
Maize is an important food crop, as well as the irreplaceable feed and industrial materials, having huge market demand in China. Southwestern region of China is the third largest main maize producing zone, and the fre... Maize is an important food crop, as well as the irreplaceable feed and industrial materials, having huge market demand in China. Southwestern region of China is the third largest main maize producing zone, and the frequent occurrence of abiotic stress conditions such as drought, heat, cold, wet shaded stress have severely affected the development of maize production, causing low and unstable corn yields, severely restricting the maize industry development in the southwest of China. This paper preliminarily describes the maize resistance to abiotic stresses in southwestem region of China, putting forward the countermeasures and the key research direction in the practice of breeding in order to provide reference for the cultivation of new varieties with high yield and stress resistance, and improving the levels of maize stress resistance breeding in southwestern region of China. 展开更多
关键词 Southwestern region of China MAIZE DROUGHT Heat Wet shaded Stress tolerance BREEDING
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The Impact of Arid Climate Change on Agriculture of Dry Valley in Southwest China and Its Adaptive Countermeasures 被引量:7
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作者 鲍文 《Agricultural Science & Technology》 CAS 2011年第5期737-740,共4页
The eco-environmental vulnerability and underdevelopment of the agriculture in Southwest China would strengthen its disadvantage conditions further on the condition of arid climate change.It is necessary to deal with ... The eco-environmental vulnerability and underdevelopment of the agriculture in Southwest China would strengthen its disadvantage conditions further on the condition of arid climate change.It is necessary to deal with the relations between resource utilization and eco-environment finely and ascertain the adaptive principles on the dry valley agriculture to the arid climate change in order to change the extensive utilization of the special agricultural resources.The paper gave some adaptive countermeasures that develop modern rangeland husbandry,strengthening the special agriculture and agricultural industrialization,emphasis on the ecological agriculture development,constructing the extension system of water-saving modern agriculture,encouraging the service industry related to "agriculture,peasants and the countryside",constructing water utilization facilities,and exploiting the renewable energies. 展开更多
关键词 ARID Climate change Southwest China Dry valley AGRICULTURE Adaptive countermeasures.
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Assessment of Genetic Diversity of Yunnan,Tibetan,and Xinjiang Wheat Using SSR Markers 被引量:25
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作者 王海燕 王秀娥 +1 位作者 陈佩度 刘大钧 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第7期623-633,共11页
A total of 206 SSR (Simple Sequence Repeats) primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were d... A total of 206 SSR (Simple Sequence Repeats) primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were detected in 31 Yunnan, 15 Tibetan and 6 Xinjiang wheat accessions with an average of PIC values 0.2764, 0.3082, and 0.1944, respectively. Substantial differences in allelic polymorphisms were detected by SSR markers in all the 21 chromosomes, the 7 homoeologous groups, and the three genomes (A, B, and D) in Yunnan, Tibetan, and Xinjiang wheat. The highest and lowest allelic polymorphisms in all the 21 chromosomes were observed in 3B and 1D chromosomes, respectively. The lowest and highest allelic polymorphisms among the seven homoeologous groups was observed in 6 and 3 homoeologous groups, respectively. Among the three genomes, B genome showed the highest, A the intermediate, and D the lowest allelic polymorphism. The genetic distance (GD) indexes within Yunnan, Tibetan, and Xinjiang wheat, and between different wheat types were calculated. The GD value was found to be much higher within Yunnan and Tibetan wheat than within Xinjiang wheat, but the GD value between Yunnan and Tibetan wheat was lower than those between Yunnan and Xinjiang wheat, and between Tibetan and Xinjiang wheat. The cluster analysis indicated a closer relationship between Yunnan and Tibetan wheat than that between Yunnan and Xinjiang wheat or between Tibetan and Xinjiang wheat. 展开更多
关键词 Yunnan wheat Tibetan wheat Xinjiang wheat genetic diversity SSR markers
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A new distribution site of the Asian Open-billed Stork (Anastomus oscitans) in southwestern China 被引量:3
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作者 蒋爱伍 宁宇新 《Chinese Birds》 2010年第4期259-260,共2页
An adult Asian Open-billed Stork (Anastomus oscitans) was observed in the Longjing reservoir of Baise City, northwestern Guangxi Zhuang Autonomous Region on 3 October 2010. It is the first record of this big stork in ... An adult Asian Open-billed Stork (Anastomus oscitans) was observed in the Longjing reservoir of Baise City, northwestern Guangxi Zhuang Autonomous Region on 3 October 2010. It is the first record of this big stork in Guangxi, southwestern ChinaThe Longjing reservoir is located in the 展开更多
关键词 Asian Open-billed Stork southwestern China
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Breeding and Cultivation Technique of Recessive Genic Male Sterility Hybrid Wheat New Variety Xinan 112
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作者 阮仁武 李中安 +5 位作者 易泽林 张建奎 傅大雄 胡丹 刘星贝 杨宇衡 《Agricultural Science & Technology》 CAS 2016年第9期2067-2069,2141,共4页
Xinan 112 is the hybrid combination(11S12) by wheat recessive genic male sterility line 2011Z1 (08L5070) and restoring line K152-2, particpating in the regional test of 2011-2012, 2012-2013 and production test of ... Xinan 112 is the hybrid combination(11S12) by wheat recessive genic male sterility line 2011Z1 (08L5070) and restoring line K152-2, particpating in the regional test of 2011-2012, 2012-2013 and production test of 2013-2014 in Chongqing. The results showed that 3 years average yield was 4 167.5 kg/hm2, which was increased 10.5% compared with CK Yumai 7, 1 000-grain weight was 45.8 g, which was 1.7 g heavier than the control; grain number per ear was 39.3, more than 1.6 grains compared with CK. The results of 2 years quality determination were: bulk density of 811 g/L, falling number of 353 s, crude protein of 15.15%, wet gluten of 31.2%, water adsorption of 62.9 ml/100 g, formation time of 5.5 min, stable time of 6.5 min, softening degree of 90 F.U., and powder quality coefficient of 96 mm. Therefore, Xinan 112 is a high yield and high protein gluten wheat variety and is suitable for cultivated in Chongqing and climate contion similar areas. 展开更多
关键词 Xinan 112 Genic male sterility Hybrid wheat
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宋代江南西路基层区划——乡的调整及相关问题研究 被引量:1
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作者 王旭 《中国历史地理论丛》 CSSCI 北大核心 2016年第1期91-98,共8页
宋代基层区划的调整主要以"乡"为单位,乡的调整方式有割、分、并、换四种。乡的调整必须考虑地方特殊的自然、人文环境,否则就会造成税收不便、风俗杂乱等问题。乡不仅在地域上有较强的稳定性,而且在调整过程中表现出难以分... 宋代基层区划的调整主要以"乡"为单位,乡的调整方式有割、分、并、换四种。乡的调整必须考虑地方特殊的自然、人文环境,否则就会造成税收不便、风俗杂乱等问题。乡不仅在地域上有较强的稳定性,而且在调整过程中表现出难以分割的特性。以往认为乡在宋代已经完全"地域化"的观点是错误的,宋代的乡可以说是一个独立的"地域空间单元",它是维系其他基层区划运作的地理空间。 展开更多
关键词 宋代 基层区划调整 西
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Survey of the use by birds of various karst wetlands in southwestern Guangxi, southern China
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作者 舒晓莲 陆舟 +3 位作者 杨岗 蒙渊君 李肇天 周放 《Chinese Birds》 CSCD 2013年第4期291-305,共15页
The limestone area located in southwestern Guangxi in the south of China is part of a global biodiversity hotspot. As an important habitat of this limestone region, karst wetlands provide birds with necessary water co... The limestone area located in southwestern Guangxi in the south of China is part of a global biodiversity hotspot. As an important habitat of this limestone region, karst wetlands provide birds with necessary water conditions for their survival and reproduction. From 2007 to 2012, bird surveys were conducted in natural wetlands(pools, streams, springs and seasonal flows) in 14 nature reserves and 18 reservoirs in the limestone area of southwestern Guangxi. A total of 365 bird species were recorded in field investigations, including 103 water-dependent birds mainly seen in wetlands. Among these 103 birds, 10 species are globally threatened and 5 species have been placed under national key protection. The birds were selective in their use of the various types of karst wetlands. The number of bird species was the highest in pools and springs, with 304 and 266 respectively, followed by streams with 131 species. Reservoirs are the main wintering habitat for the large Natatores and in the rainy season the importance of seasonal flows is paramount. Seasonal changes in the utilization of karst wetlands by birds were obvious; the number of bird species in the dry season was much higher than during the rainy season. Bird migration and seasonal flows are the main reasons for seasonal variation in the number of water-dependent birds. These natural karst wetlands ensure the drinking water supply for more than 80% of the water-independent birds in the dry season. These karst wetlands are the wintering ground and stopover area for 58 species of migrant birds. At present, threats to the birds in the karst wetlands consist of illegal hunting, habitat changes and eucalyptus plantations. Karst wetlands are important for protecting biodiversity. More attention ought to be directed to these wetlands and protection efforts enhanced. 展开更多
关键词 karst wetlands limestone area BIRDS southwestern Guangxi conservation
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Study on Soil Erosion Model Under Different Slopes in Southwest Karst Mountain Area
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作者 高翔 王济 +1 位作者 蔡雄飞 胡丰青 《Agricultural Science & Technology》 CAS 2013年第12期1847-1851,共5页
The aim was to further research soil erosion characteristics and accurately predict soil erosion amount in karst areas. Based on field surveys and research achievements available, yellow soils, which are widely distri... The aim was to further research soil erosion characteristics and accurately predict soil erosion amount in karst areas. Based on field surveys and research achievements available, yellow soils, which are widely distributed, were chosen as test soil samples and slope, rain intensity, vegetation coverage and bare-rock ratio were taken as soil erosion factors. Artificial rain simulation instruments (needle-type) were made use of to simulate correlation of rain intensity, vegetation coverage, and bare-rock ratio with soil erosion quantity. Furthermore, multiple-factor linear regression analysis, stepwise regression analysis and multiple-factor non-linear regression analy- sis were made to establish a multiple-factor formula of soil erosion modulus with dif- ferent slopes and select regression models with high correlation coefficients. The re- sults show that a non-linear regression model reached extremely significant level or significant level (0.692〈FF〈0.988) and linear regression model achieved significant lev- el (0.523〈FF〈0.634). The effects of erosion modulus changed from decreasing to in- creasing and the erosion factors from high to low were rain intensity, vegetation cov- erage and bare-rock ratio when slope gradient was at 6~, 16~, 26~ and 36~. The mod- el is of high accuracy for predicting gentle slope and abtupt slope, which reveals correlation of erosion modulus with erosion factors in karst areas. 展开更多
关键词 Southwest karst mountain area SLOPE Soil erosion model
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试析史炤《资治通鉴释文》中的方言现象 被引量:1
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作者 陆华 《宝鸡文理学院学报(社会科学版)》 2004年第2期89-91,共3页
史炤《资治通鉴释文》三十卷是一本作于南宋时期的音义著作,其中大量的音切集中反映了宋代的语音特点,其中的方言现象反映着客家方言定型早期的特征,既保留唐时旧音,同时又含有近、现代客家方言的音韵特点。
关键词 资治通鉴释文 方言现象 客家方言 西官话
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Summer-autumn habitat use by Galliformes in a primary forest,southeastern Tibet 被引量:4
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作者 卢欣 《Chinese Birds》 2012年第2期113-117,共5页
Habitat use by Galliformes in an ornithologically unexplored region,a forest area in southeastern Tibet,was investigated during the summer and autumn periods of 1995.A total of seven species were recorded,most of whic... Habitat use by Galliformes in an ornithologically unexplored region,a forest area in southeastern Tibet,was investigated during the summer and autumn periods of 1995.A total of seven species were recorded,most of which preferred habitats on south-facing slopes and avoided those on north-facing slopes where conditions were relatively humid.A hybrid population of White (Crossoptilon crossoptilon) versus Tibetan Eared-pheasants (C.harmani) was predominant among the Galliforme community,followed by Blood Pheasants (Ithaginis cruentus) and Chinese Grouse (Bonasa sewerzowi).A further investigation in 2001 showed that on account of little human activity in the distant primary forests,the birds suffered less of a threat from hunting and habitat disturbance. 展开更多
关键词 CONSERVATION GALLIFORMES habitat use primary forest southeastern Tibet
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丙烯酸-2,4,6-三硝基苯乙酯的合成及热分解 被引量:2
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作者 刘强强 金波 +3 位作者 彭汝芳 舒远杰 楚士晋 董海山 《含能材料》 EI CAS CSCD 北大核心 2012年第5期579-582,共4页
以TNT、甲醛为原料,在弱碱性条件下反应合成得到2,4,6-三硝基苯乙醇(PicCH2CH2OH);PicCH2CH2OH在浓硫酸催化下和丙烯酸在甲苯中回流反应24h,合成得到丙烯酸-2,4,6-三硝基苯乙酯,产率为62%。采用紫外可见光谱(UV-Vis)、核磁共振氢谱(1HN... 以TNT、甲醛为原料,在弱碱性条件下反应合成得到2,4,6-三硝基苯乙醇(PicCH2CH2OH);PicCH2CH2OH在浓硫酸催化下和丙烯酸在甲苯中回流反应24h,合成得到丙烯酸-2,4,6-三硝基苯乙酯,产率为62%。采用紫外可见光谱(UV-Vis)、核磁共振氢谱(1HNMR)、红外光谱(FTIR)、质谱(MS)以及元素分析等对产物结构进行了表征。利用热重分析(TG)对产物热稳定性进行了研究,采用Kissinger方法和Ozawa方法计算其热分解活化能Ea分别为99.78,102.96kJ·mol-1。 展开更多
关键词 有机化学 2 4 6-三硝基苯乙醇 丙烯酸-2 4 6-三硝基苯乙酯 热稳定性 活化能
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场离子显微镜在析出强化微合金钢中的应用
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作者 朱晓勇 王晓姣 +2 位作者 钟柳明 刘庆冬 刘文庆 《材料热处理学报》 EI CAS CSCD 北大核心 2011年第7期51-56,共6页
将实验V-Nb-Mo微合金钢在1200℃固溶处理,在500℃回火不同时间,用场离子显微镜(FIM)研究实验钢中碳化物的析出过程。结果表明:回火0.5 h的样品中,碳化物处于形核长大时期,与基体的{110}呈共格关系;随着回火时间的延长,碳化物形成独立的... 将实验V-Nb-Mo微合金钢在1200℃固溶处理,在500℃回火不同时间,用场离子显微镜(FIM)研究实验钢中碳化物的析出过程。结果表明:回火0.5 h的样品中,碳化物处于形核长大时期,与基体的{110}呈共格关系;随着回火时间的延长,碳化物形成独立的晶体结构,与基体{110}之间呈半共格关系;回火100 h后,碳化物粗化长大,与基体呈非共格关系;形状系数随着回火时间的延长先变大再变小,析出相尺寸从1.6 nm逐渐增大至15 nm。500℃回火30 h的实验钢力学性能最佳,表明碳化物的析出强化效果最明显,相应的碳化物尺寸约为4 nm。 展开更多
关键词 场离子显微镜 回火 析出 V-Nb-Mo微合金钢
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Genetic Diversity of Gli-1,Gli-2 and Glu-1 Alleles Among Chinese Endemic Wheats 被引量:16
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作者 魏育明 郑有良 +4 位作者 周永红 刘登才 兰秀锦 颜泽洪 张志清 《Acta Botanica Sinica》 CSCD 2001年第8期834-839,共6页
Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 32 accessions of Chinese endemic wheat by using acid polyacrylamide gel electrophoresis (APAGE) and sodium dodecyl sulfate (SDS)_PAGE. There were 8 ... Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 32 accessions of Chinese endemic wheat by using acid polyacrylamide gel electrophoresis (APAGE) and sodium dodecyl sulfate (SDS)_PAGE. There were 8 gliadin and 3 high_molecular_weight (HMW)_glutenin patterns in 14 Yunnan hulled wheat ( Triticum aestivum ssp. yunnanese King) accessions, 9 gliadin and 4 HMW_glutenin patterns in 9 Tibetan weedrace ( T. aestivum ssp. tibetanum Shao ) accessions, and 9 gliadin and 5 HMW_glutenin patterns in 9 Xinjiang rice wheat ( T. petropavlovskyi Udacz. et Migusch.) accessions. One accession (i.e. Daomai 2) carried new subunits 2.1+10.1 encoded by Glu_D1. Among the three Chinese endemic wheat groups, a total of 10, 14 and 11 alleles at Gli_1 locus; 11, 14 and 12 alleles at Gli_2 locus; and 5, 6 and 8 alleles at Glu_1 locus were identified, respectively. Among Yunnan hulled wheat, Tibetan weedrace and Xinjiang rice wheat, the Nei's genetic variation indexes were 0.3798, 0.5625 and 0.5693, respectively. These results suggested that Tibetan weedrace and Xinjiang rice wheat had higher genetic diversity than Yunnan hulled wheat. 展开更多
关键词 Yunnan hulled wheat Tibetan weedrace Xinjiang rice wheat genetic diversity gliadin alleles high_molecular_weight (HMW)_glutenin alleles
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Studies on Rapid Extension of Guangxi Hybrid Rice Varieties in Vietnam
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作者 周行 刘百龙 +3 位作者 王威豪 伍豪 石瑜敏 韦善富 《Agricultural Science & Technology》 CAS 2016年第7期1551-1555,1576,共6页
Based on the similarity in geographic and climatic conditions between Guangxi and Vietnam, a new extension model, i.e., variety prescreening test in Nanning-variety screening tests in Vietnam-multi-location test and d... Based on the similarity in geographic and climatic conditions between Guangxi and Vietnam, a new extension model, i.e., variety prescreening test in Nanning-variety screening tests in Vietnam-multi-location test and demonstration in Vietnam-commercial production in Vietnam, was put forward for rapid extension of the hybrid rice varieties from Guangxi, China in Vietnam. Through practice, this model had a very good effect on a group of hybrid rice varieties like Teyou 136 selected for rapid extension in Vietnam. Besides, some suggestions were offered for the extension of Guangxi hybrid rice varieties in Vietnam. 展开更多
关键词 GUANGXI China hybrid rice VIETNAM
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Seasonal Dynamics of Photosynthetic Response for Young Tree of B. macrostachya in Seasonal Rain Forest
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作者 栗忠飞 郑征 《Agricultural Science & Technology》 CAS 2012年第6期1251-1253,1259,共4页
[Objective] The aim was to study on biological characteristics of photosynthetic response for young trees of B. macrostachya in seasonal rain forest, providing scientific reference for protection of tropical rain fore... [Objective] The aim was to study on biological characteristics of photosynthetic response for young trees of B. macrostachya in seasonal rain forest, providing scientific reference for protection of tropical rain forest under change of global climate. [Method] Young trees of B. macrostachya in Xishuangbanna tropical forest were chosen to research in foggy season, dry and hot season, and rainy season to measure dynamics of season changes. [Result] For young trees of B. macrostachya in Yunnan Province, Pn max was the biggest in rainy season, followed by dry and hot season and foggy season at 4.08, 2.89 and 1.81 μmol/(m·s) respectively; Gs and Tr in rainy season were the highest and WUE in dry season was the highest; Gi achieved peak in foggy season, of which the highest values were 0.18 and 1.59 mmol/(m 2 ·s), and 7.35 μmol/mmol and 455 mmol/(m 2 ·s); Ci showed an opposite trend with that of WUE, and Gs and Tr changed similarly. [Conclusion] Young trees of B. macrostachya in seasonal rain forest are of significant seasonal change in photosynthetic response, and young trees are shade tolerant. 展开更多
关键词 Seasonal forest Barringtonia macrostachya (B. macrostachya) Photosynthetic characteristics XISHUANGBANNA
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