环
- 与 环 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Dicyclopentadiene ; Cyclopentadiene ; Raney Nickel ; Liquid hydrogenation ; Cyclopentene
双环戊二烯;环戊二烯;骨架镍;液相加氢;环戊烯
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In this research FGA was synthesized through total ten steps such as epoxidation via H2O2, carbonyl protection, LiAlH2 reduction、carbonyl deprotection, epoxidation and ring opening with HF, oxidation, bromination and debromination et al.
设想通过对蕃麻二烯物进行H2O2环氧化、羰基保护、LiAlH4还原、羧基脱保护、溴羟环氧、HF开环、氧化、上溴脱溴等一系列反应得到FGA。
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The preparation of grafted derivant of tertiary amine: it is prepared by the reacting of above (1) product and (2) product heated in water bath at 40℃ within 10min.
聚环氧氯丙烷乙二醇哌啶接支衍生物的制备:将上面制备的聚环氧氯丙烷乙二醇与0.25mol环氧丙基哌啶叔胺于40℃水浴条件下进行接支反应。
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In the second part of this thesis, a formal [2+2] cycloaddition ketenes and dialkyl azodicarboxylates was studied. We found that by adjusting the substituents in the diazenes, the reaction mode can be completely switched, and furnish four-membered-ring products, aza-b-lactams, the enantioselectivity was up to 91%.
经研究发现,通过对偶氮化合物取代基团的改变,我们可以实现[4+2]环加成反应到[2+2]环加成反应的转变,在手性氮杂环卡宾的作用下,对具有各种取代基的烯酮都可以很好的产率得到氮杂b-内酰胺,其对映选择性最高可以达到91%。
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In this paper, the host-guest relationship between a general cucurbit [n=7] uril (Q[7]) or a new ellipsoid-host-symmetric tetramethyl-cucurbituril (TMeQ[6]) with hydrochloride salts of 4,4'-dipyridyl (44) or N,N'-dimethyl-4,4'-dipyridyl(dm44) was examined for confirming the interaction between cucurbituril (Q[6]) and these guests.
以七元瓜环(Q[7])和新型椭圆型改性瓜环―对称四甲基取代六元瓜环(TMeQ[6])为主体,4,4'-联吡啶的盐酸盐(44)以及N,N'-二甲基4,4'-联吡啶的盐酸盐(dm44)为客体的主客体相互作用进行了考察。
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It has become the restrictive factor of economic development. The implement of water saving rebuild programming in northern droughty areas is an important measure for sustainable use of water.This study is based on the investigation of the type, step and method of SEA, and focuses on the water saving rebuild programming in Mongolia Hetao regions as a case. The SEA technique is applied to agricultural sustaining using of water. The contents and impact factors are summarized along with the objective and standards defined clearly. This paper also offers assessment indexs on water saving rebuild programming, which evaluates the subsequent environmental impacts and public benefits. Some measures avoiding the negative impact are also presented to ensure that this programming is in accordance with the principle of sustainable development.
本论文在对战略环评的类型、步骤和方法进行充分调研的基础上,针对内蒙河套灌区水资源可持续利用的节水改造规划,将战略环评的相关方法应用到灌区农业水资源的可持续利用战略中,概括其环境评价所涵盖的内容,分析总结相关的影响因子,明确评价目标和标准,尤其突出战略环评在节水改造规划应用中的评价指标,重点评价灌溉节水改造规划实施后,对环境产生的影响及其环境经济效益,并提出减缓负面影响的保护措施,使这一规划在实施过程中更加符合可持续发展的原则。
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An alicyclolic epoxy resin with endocyclic structure,namely hydrogenated terpinene-maleic ester type epoxy resin, was synthesized from the raw material hydrogenated terpinene-maleic anhydride.
以氢化萜烯马来酸酐为原料与环氧氯丙烷反应合成一种含桥环结构的饱和脂环基环氧树脂——氢化萜烯酯型环氧树脂。
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Other methyl nucleophiles includingMeMgBr, MeCeCl2, MeTiCl3, Me3Al, Me3ZnMgCl, MeMnClwere tried, but in all these cases no detectable amount of exo-C8-methylated product was obtained. Although protecting C3-carbonyl as 1,3-dioxolanes could be achieved, the serious enolization of C8-carbonyl was still problematic. Converting C9-furan ring to α,β-butenolide did depress the enolization, but desired C8-methylation was completely replaced by migration of the double bond of the butenolide.
在本论文的早期阶段,主要着眼于解决二环[3.2.1]-C8-羰基加成甲基所遇到的C9-呋喃环差向异构化和C3与C8两个羰基之间化学选择性的问题:通过引入不同金属降低甲基试剂的碱性并没有取得甲基化的成功;通过不同的方法将C3-羰基掩蔽,但是C8-羰基的烯醇化依然无法抑制;虽然通过将呋喃环转化为α,β-不饱和-γ-丁内酯可以抑制烯醇化,但内酯环上的双键迁移又成了新的竞争反应。
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Using butanediol as initiator, boron-trifluoride etherate as catalyst, 3-azidomethyl-3-methyloxetane homopolymer was synthesized by the cationic polymerization of 3-azidomethyl-3-methyloxetane which was carried out in dichlorometane.
以1,4-丁二醇为引发剂,以三氟化硼乙醚络合物为催化剂,以3-叠氮甲基-3-甲基氧丁环为单体,以CH2Cl2为溶剂,按阳离子开环聚合机理,合成了含能粘合剂3-叠氮甲基-3-甲基氧丁环均聚物。
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The PAHs in sediment core were mainly composed of phenanthrene and fluorene. The concentrations of phenanthrene and fluorene in sediment core were 236.1-417.9 ng/g and 91-130.8 ng/g,respectively. Both of them accounted for 47.2%-58.1% of the ∑PAH16 in sediments.
沉积物中多环芳烃的组成以3环的菲和芴为主,它们的含量分别为236.1~417.9 ng/g和91~130.8 ng/g,二者共占沉积物中多环芳烃总量(∑PAH16)的47.2%~58.1%。
- 推荐网络例句
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Do you know, i need you to come back
你知道吗,我需要你回来
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Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.
1〕 杨银书,王祥生,李德昌。安徽省首次发现嗜群血蜱。
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Chapter Three: Type classification of DE structure in Sino-Tibetan languages.
第三章汉藏语&的&字结构的类型划分。