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A synthesis of 2-pentylidene cyclopentanone starting from cyclopentanone and n-valeraldehyde through aldol condensation, followed by dehydration, was studied, and the yield reached 85.6%. 2-Pentenyl cyclopentanone was prepared in a yield of 95.0% from 2-pentylidene cyclopentanone with a hydrogenation methodology. Through Baeyer-villiger oxidation,δ-decalactone was synthesized in a yield of 63.9% from 2-pentenyl cyclopentanone with hydrogen peroxide.

研究了以正戊醛和环戊酮为起始原料，经羟醛缩合、脱水反应合成2-戊叉环戊酮，产率达到85.6%，2-戊叉环戊酮加氢制备2-戊基环戊酮，产率为95.0%，2-戊基环戊酮在双氧水作用下经Baeyer-villiger氧化重排反应合成δ-癸内酯，反应产率为63.9%，合成δ-癸内酯的总产率为52.0%，气相色谱分析纯度为98.7%。

Highly significant differences were observed between the locations and years for fresh yield, defoliated yield and dry yield.

结果显示，在南非纳塔尔地区，红麻产量的基因型和环境相互作用显著。

Tumorous stem yield was only significantly hereditarily positively correlated with vegetative duration, developmental duration, ratio of stem and leaf, horizontal length and whole plant fresh weight, negatively fur percentage and tumorous stem index. There were close relation and harmonies among the quantities characters that were significantly hereditarily correlated with tumorous stem yield. High yield breeding combining with strong ecological adaptability and good quality should be largely based on later maturity, tumorous stem diameter, whole plant weight and higher ratio of stem and leaf.

瘤茎产量与营养生长期、瘤茎膨大期、瘤茎横径、茎/叶、株鲜重呈极显著遗传正相关，与菜形指数、菜皮百分率呈极显著遗传负相关，与其余性状相关均未达显著水平；与瘤茎产量显著相关的性状间关系密切，有很好的协同性，分析提出茎瘤芥育种选择熟性晚、瘤茎横径大、茎/叶高和植株个体较大的品种，可实现品种产量高、生态适应性强和瘤茎品质较佳等三者的协调统一。

Amino-6-nitrobenzodifuroxan was prepared through a three-step reaction from starting material 3, 5-dinitrobenzoic acid:(1)3, 5-dinitroaniline (1) was synthesized from the reaction of DNBA and hydrazoic acid in inert solvent 1, 2-dichioroethane through Schmidt rearrangement with yield of 89.6%;(2) 1 was subjected to nitration to prepare pentanitroaniline (2) with yield of 51.1%;(3) The title compound was prepared from 2 and sodium azide in acetic acid through denitrogenation and then Schmidt rearrangement with yield of 86.8%, m.p.204℃～206℃.

以3，5-二硝基苯甲酸为原料经过3步反应合成了7-氨基6-硝基苯并二氧化吠咱：第1步反应，在二氯乙烷惰性溶剂中，DNBA与叠氮酸反应并发生Schmidt重排反应生成3，5-二硝基苯胺(1)，产率89.6%；第2步反应，1在含100%硫酸的硝硫混酸中硝化生成五硝基苯胺(2)，产率51.1%；第3步反应，2与叠氮酸反应，不经分离直接进行热解脱氮、Schmidt重排反应，得到目标化合物， m.p.204℃~ 206℃，产率86.8%。

The effect of harvesting height on the grass yield and quality of two varieties of Lolium multiflorum was studied and the result showed that the different harvesting height greatly affected the fresh yield, dry mater yield, quality and growth characteristics.

多花黑麦草Lolium multifolium具有很强的再生性和耐刈性，为了确定最佳的刈割利用方式，在有限的耕地中获得较高的产量和效益，采用小区试验的方法，研究了不同刈割高度对多花黑麦草特高和杰威产草量和品质的影响。

Meteorologic data and rice yield data were analyzed in Xinyang from 1991 to 2004, and the reason of yield's decreasing was intense change of sunlight and temperature from July to September, and the rice yield was reduced by 28.28% compared with average of recent five years.

通过对信阳地区1991—2004年的气象数据和水稻产量数据的分析，发现2003年水稻的减产是由于7—9月光温条件的剧烈变化所造成，产量相比近五年平均（2000—2004年）降低了28.28%。

Bis-imidazoline was prepared from triethylene tetraamine and N,N-dimethylformamide dimethyl acetal at 85℃ for 2 h with toluene as solvent, with a yield of 90.4%. The reaction of bis-imidazoline with 1,2-dibromoethane and potassium carbonate in acetonitrile provided with a monobromide salt yield of 78.7%. Hydrolysis of monobromide salt under aqueous causic solution formed 1,4,7,10-tetraazzcyclododecane in a 74.2% yield.

用甲苯作溶剂，使三乙烯四胺和N，N-二甲基甲酰胺二甲基缩醛在85℃反应2 h，得到中间体双咪唑啉，产率90.4%，在乙腈溶剂中，碳酸钾存在下，双咪唑啉和1，2-二溴乙烷进行扩环反应，得到环状中间体一溴盐，产率78.7%，一溴盐经碱性水解2 h，得到1，4，7，10-四氮杂十二烷，产率74.2%。

In order to provide theoretical basis and technological for high-quality and high-yield cultivation of a strong gluten wheat variety,Jimai 20,the experiment studied effects of the radio of nitrogenous fertilizer and potassic fertilizer on yield and qualitly of Jimai 20 under the field conditions with High-yield cultivation.

为了给强筋小麦品种济麦20优质高产配套栽培提供理论依据及技术支撑，在大田高产栽培条件下，研究了氮钾肥施用量及其配比对强筋小麦品种济麦20产量和品质的影响。

The final yield showed that the yield of plastic ridging and furrow drilling increased yield of conventional flat planting 1472.10 kg/hm^2, increased by 19.3%; increased 1844.79 kg/hm^2 compared with ridging and furrow drilling, increased by 25.4%, differences between different treatments were up to super remarkable level.

最终产量测定，起垄覆膜沟播冬小麦极显著的高于传统平作，比传统平作栽培高1472.10 kg/hm^2，增产幅度19.3%；比起垄沟播冬小麦最终产量高1 844.79 kg/hm^2，增产25.4%，差异均达到极显著水平。

The thermal property studies indicate that the mass loss of compound B was 54.39% at 242.2~750℃, and when the temperature was 1000℃, there was 25.11% char residue left, which showed that the title compound has a good thermal stability and char forming capability. Using acetonitrile as the solvent instead of trichloromethane or 1, 2-dichloethane gave higher yield. During the synthesis, the yield was very low when triethylamine was used as acid acceptor alone, and when a little amount of 4-dimethylaminopyridine was added at the same time, the yield could be 81%.

结果表明，所合成的化合物B的结构与预期的结构一致；热性能研究表明，化合物B在242.2~750℃质量损失为54.39%，1000℃时仍有25.11%的炭残渣，显示出优异的热稳定性和成炭性；在相同反应条件下，用乙腈作为溶剂的反应产率比使用氯仿和二氯乙烷为溶剂的高，并且在合成过程中，单独使用三乙胺作为缚酸剂时产率很低，而当同时加入少量4-二甲氨基吡啶时，产率可达81%。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐