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江苏省农业后备资源数量构成及特点
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作者 青爱 《南京农专学报》 2002年第3期95-95,共1页
关键词 江苏 农业后备资源 数量构成 特点
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俄藏黑水城金代文献的数量、构成及其价值 被引量:2
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作者 孙继民 《敦煌研究》 CSSCI 北大核心 2012年第2期9-14,共6页
《俄藏黑水城文献·附录·叙录》标注的金代文献共有18个编号,其中若干编号已被证实不属于金代文献,而被认定为其他朝代的若干编号实际上是金代文献。根据目前掌握的材料,俄藏黑水城文献中至少应有20个编号的金代文献。这些文... 《俄藏黑水城文献·附录·叙录》标注的金代文献共有18个编号,其中若干编号已被证实不属于金代文献,而被认定为其他朝代的若干编号实际上是金代文献。根据目前掌握的材料,俄藏黑水城文献中至少应有20个编号的金代文献。这些文献对研究金代的历史、文化、宗教具有重要价值。本文着重介绍了几件社会文书对研究金代猛安谋克制度、兵役制度和军事制度等一些细节问题所蕴涵的独特资料价值。 展开更多
关键词 黑水城 金代文献 数量构成 文献价值
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大川河虎嘉鱼数量变动及其原因的探讨 被引量:6
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作者 吴万荣 《水产科技情报》 1988年第5期3-6,共4页
虎嘉鱼Hucho bleeker kimura是长江上游的濒危珍稀鱼类,数量极其稀少,分不布极为狭窄。十多年来。四川西部,陕西太白等地陆续发现虎嘉鱼。但是,其确切的分布区域却很少报道,数量资料更为少见。为此,本文就四川芦山虎嘉鱼的分布区... 虎嘉鱼Hucho bleeker kimura是长江上游的濒危珍稀鱼类,数量极其稀少,分不布极为狭窄。十多年来。四川西部,陕西太白等地陆续发现虎嘉鱼。但是,其确切的分布区域却很少报道,数量资料更为少见。为此,本文就四川芦山虎嘉鱼的分布区域,数量构成。产卵群体作一初步报道。并探讨其数量变动原因,为保护、繁殖虎嘉鱼提供科学依据。 展开更多
关键词 虎嘉鱼 分布区域 数量构成 大川河 产卵群体
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编辑基本规律研究的几个问题 被引量:3
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作者 禤胜修 《出版科学》 CSSCI 北大核心 2014年第1期31-34,共4页
通过对编辑基本规律已有研究的考察,对编辑基本规律的研究范畴、理论界定、数量构成、语言表述四个问题进行讨论,认为:编辑基本规律的研究范畴应限定在编辑活动本身;编辑基本规律是编辑活动的普遍规律,是运用各种编辑形式的总原则,决定... 通过对编辑基本规律已有研究的考察,对编辑基本规律的研究范畴、理论界定、数量构成、语言表述四个问题进行讨论,认为:编辑基本规律的研究范畴应限定在编辑活动本身;编辑基本规律是编辑活动的普遍规律,是运用各种编辑形式的总原则,决定各种编辑形式的具体规则并体现在各种编辑形式之中;"编辑基本规律只能有一条"的说法过于武断,无益于编辑基本规律的深入探讨;"内容+规律(律)"的格式是编辑基本规律的最优表述形式。 展开更多
关键词 编辑基本规律 研究范畴 理论界定 数量构成 语言表述
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雁门关农牧交错带娄烦县鼠类的分布和区系组成 被引量:1
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作者 邹波 张永丽 +2 位作者 王振华 侯玉 王庭林 《农业技术与装备》 2020年第5期158-160,共3页
文章以捕获实物标本为依据,对地处雁门关农牧交错带南端的太原市水源地-娄烦地区鼠类的分布和区系组成进行了调查。查明娄烦县12种鼠类,隶属四科九属,区系从属关系为古北界的种类9种,占75.00%;东洋界的种类1种,占8.33%;广布种的种类2种,... 文章以捕获实物标本为依据,对地处雁门关农牧交错带南端的太原市水源地-娄烦地区鼠类的分布和区系组成进行了调查。查明娄烦县12种鼠类,隶属四科九属,区系从属关系为古北界的种类9种,占75.00%;东洋界的种类1种,占8.33%;广布种的种类2种,占16.67%。该区鼠的种类占全国鼠的种类的5.56%,占整个黄土高原鼠种类的24.49%,占山西省鼠种类的52.17%,海拔高度1200~1500 m的黄土丘陵地带为鼠类的集中分布区,共有11种鼠类分布,海拔高度1200m以下的河谷地带分布的鼠种较少,只有4种鼠类分布。丘陵地带和河谷地带秋季捕鼠平均夹捕率为8.82%。 展开更多
关键词 鼠类 分布 区系 数量构成 雁门关农牧交错带
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禾本科草类在新疆天然草地中的地位 被引量:5
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作者 张国平 郭成 《草食家畜》 2001年第2期33-36,共4页
本文从新疆天然草地建群优势种的种类组成入手 ,从资源数量、构建草地型数量、建群优势种数量及草地类相关要素的分析等方面对禾本科草类进行了比较全面的分析 。
关键词 禾本科草类 新疆 天然草地 资源 优势种数量构成 草地型数量构成
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比较——教类同应用题的关键
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作者 徐必华 《湖北教育》 1996年第5期39-39,共1页
教材对应用题的 教学,是归类安排的。根据这一编排特点,引导学生对类同应用题进行比较是关键。比较异同,一是有利于强化学生的认知结构,二是有利于释疑,培养学生的观察和比较能力。 例如:1.绿化祖国采集树种,二年级有4个班,每班采集20千... 教材对应用题的 教学,是归类安排的。根据这一编排特点,引导学生对类同应用题进行比较是关键。比较异同,一是有利于强化学生的认知结构,二是有利于释疑,培养学生的观察和比较能力。 例如:1.绿化祖国采集树种,二年级有4个班,每班采集20千克,四年级有3个班,每班采集25千克。两个班一共采集树种多少千克?(解法:20×4+25×3) 展开更多
关键词 应用题 第二种解法 条件部分 作业本 比较异同 编排特点 第1题 比较能力 数量构成 认知结构
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Responses of Seed Yield and Economic Benefit of Winter Oilseed Rape(Brassica napus L.) to Different NPK Ratio and Dose 被引量:2
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作者 Yingzi WANG Chang TIAN +5 位作者 Xuan ZHOU Wenming WANG Jianwei PENG Zhenhua ZHANG Haixing SONG Chunyun GUAN 《Agricultural Science & Technology》 CAS 2015年第11期2361-2366,共6页
Field experiments were conducted during 2008-2010 to investigate the ef- fects of NPK fertilization on seed yield and economic benefit of a new hybrid cultivar of winter oilseed rape (Brassica napus L.) - Xiangzayou... Field experiments were conducted during 2008-2010 to investigate the ef- fects of NPK fertilization on seed yield and economic benefit of a new hybrid cultivar of winter oilseed rape (Brassica napus L.) - Xiangzayou763, and to determine the optimum NPK ratio and dose in Hunan, China. The results showed that NPK ratio (1:0.50:0.50) with 180 kg/hm2 N, 90 kg/hm2 P2O5 and 90 kg/hm2 K20 was the optimum combination for the highest seed yield (2 231.13 kg/hm2) and economic benefit (9 816.97 Yuan/hm2), of which 1 641.23 Yuan/hm2 being set for fertilizer in- vestment (VCR=4.11). Besides, the effects of N, P and K fertilizers on seed yield and oil production of winter oilseed rape were not identical. N had the greatest ef- fect on plant growth of winter oilseed rape, followed by P and K. Total leaf number, green leaf number, leaf length and width, rhizome diameter, branch number, dry weight per plant and other agronomic characters in high N treatments were higher than those in low N treatments. By correlation and path analysis of yield components, the contribution rate to seed yield was found: effective silique number per plant〉seed number per silique〉l 000-seed weight. 展开更多
关键词 NPK ratio anddose Seed yield Economic benefit Winter oilseed rape
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Effects of Subsoiling on Some Soil Physical Properties and Wheat Yield in a Dry Land Ecological Condition
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作者 S. Afzalinia A. A. Solhjou I. Eskandari 《Journal of Agricultural Science and Technology(A)》 2011年第6期842-847,共6页
In order to evaluate the effect of subsoiling on the soil physical properties and wheat yield in dry land conditions, this research was conducted in Mamassani area of Fars province in Iran. The experiment was laid dow... In order to evaluate the effect of subsoiling on the soil physical properties and wheat yield in dry land conditions, this research was conducted in Mamassani area of Fars province in Iran. The experiment was laid down in the form of a complete block experimental design with four treatments and four replications for three years. Treatments included: (1) conventional tillage without using subsoiler which was control treatment (So); (2) using subsoiler with the shank space of 40 cm which was equal to the subsoiling depth (SO; (3) using subsoiler with the shank space of 60 cm which was 1.5 times of the subsoiling depth (S2); and (4) using subsoiler with the shank space of 80 cm which was 2 times of the subsoiling depth (S3). Subsoiling depth was set at 40 cm which was the lower limit of the hard pan depth in the soil. Soil cone index, soil bulk density, soil moisture content, wheat yield, and yield components were measured in this study and SAS software was used to analyze the collected data. Results showed that subsoiling decreased the soil bulk density and cone index, and increased water retention of the soil. Results also revealed that applying subsoiler increased wheat yield and yield components in our dry land conditions. Since subsoiling improved soil physical conditions and increases wheat yield, applying subsoiler in such a dry land conditions is therefore recommended. Results of this study also showed that subsoiling with the shank space of 40 cm and 60 cm had better performance compared to the shank space of 80 cm. On the other hand, shank space of 40 cm reduced the subsoiler effective working width and consequently effective field capacity. Therefore, subsoiler with a shank space of 60 cm is recommended for application in dry land soils of our type. 展开更多
关键词 SUBSOILING soil physical properties dry land conditions wheat yield.
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青海省饲用灌木半灌木植物及其利用评价 被引量:2
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作者 孙海松 《当代畜牧》 2004年第7期28-30,共3页
对青海省草地饲用灌木、半灌木植物的数量构成、分布及其在草地中的作用及饲用价值进行了统计分析,旨在为开辟牧业区的饲料资源提供资料。
关键词 青海 饲用灌木半灌木植物 利用评价 生态环境 数量构成
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Abelianness of the “missing part” from a sheaf category to a module category 被引量:2
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作者 CHEN JianMin LIN YaNan RUAN ShiQuan 《Science China Mathematics》 SCIE 2014年第2期245-258,共14页
This paper investigates the structure of the"missing part"from the category of coherent sheaves over a weighted projective line of weight type(2,2,n)to the category of finitely generated right modules on the... This paper investigates the structure of the"missing part"from the category of coherent sheaves over a weighted projective line of weight type(2,2,n)to the category of finitely generated right modules on the associated canonical algebra.By constructing a t-structure in the stable category of the vector bundle category,we show that the"missing part"is equivalent to the heart of the t-structure,hence it is abelian.Moreover,it is equivalent to the category of finitely generated modules on the path algebra of type An-1. 展开更多
关键词 tilting object torsion pair weighted projective line factor category T-STRUCTURE
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