We substituted several environmentally friendly catalysts which included HY and H- β zeolites, various cation-exchanged β zeolites, and solid-supported ferric chloride for conventional catalysts for the synth...We substituted several environmentally friendly catalysts which included HY and H- β zeolites, various cation-exchanged β zeolites, and solid-supported ferric chloride for conventional catalysts for the synthesis of 3-(1-cyclohexenyl)-2-butanone from the reaction of ethylidenecyclohexane with acetic anhydride at room temperature. HY zeolite was found to be the most effective for this reaction, and gave the acylated product in a 72% yield under the conditions of n (ethylidenecyclohexane)/ n (acetic anhydride)/ m (HY zeolite)=1 mmol/10 mmol/0 100 g, reaction temperature 25 ℃ and reaction time 2 h. The used HY zeolite can be recovered, regenerated and gave almost the same yield as the fresh one. The lifetime of the HY zeolite is over 80 h. The effect of different factors on the reaction has also been investigated.展开更多
Bloomsbury Academic By 2025,China will have built 15 new＂super cities＂each with 25 million inhabitants.It will also have created 250＂eco-cities＂which will be clean,green,car-free,peoplefriendly and hi-tech urban c...Bloomsbury Academic By 2025,China will have built 15 new＂super cities＂each with 25 million inhabitants.It will also have created 250＂eco-cities＂which will be clean,green,car-free,peoplefriendly and hi-tech urban centers.The urban environmental turnaround experiment may provide valuable experience for cities worldwide.Austin Williams,a correspondent of the Architectural Review to China.展开更多
1.care about,care for,take care of (1)这三个动词短语均可表示"喜欢…‘关心"之意,后接n.或v.-ing形式作宾语。He cared nothing about/for skating.他对滑冰没有兴趣。In our class,we care for/about each other.
1.Complete the map of each site based on what you hear on the tape. 1)based on what you hear on the tape是过去分词短语,在句子中作定语,修饰site。be based on意为"以……为根据"。This novel is based on historica...1.Complete the map of each site based on what you hear on the tape. 1)based on what you hear on the tape是过去分词短语,在句子中作定语,修饰site。be based on意为"以……为根据"。This novel is based on historical facts.展开更多
一、重点单词1.spread【考纲释义】vt.& vi.传播;伸展;展开【备考实例】Papermaking began in China and from here it ____ to North Africa and Europe. A.grew B.carried C.spread D.developed【考点解析】句意"
January 18th,Bayer Material Science (BMS)and the Changzhou Research Institute (CRI)participated ina signing ceremony for cooperation to promote thewaterborne coatings
As a chain effect of its accelerated urbanizationand industrialization, the Chinesesociety is expecting a soaring demand onhousing for years ahead. The Powder Coatingsunit of AkzoNobel China not just readsthis as a si...As a chain effect of its accelerated urbanizationand industrialization, the Chinesesociety is expecting a soaring demand onhousing for years ahead. The Powder Coatingsunit of AkzoNobel China not just readsthis as a signal of enormous businessopportunities, but also an urge for takingprompt actions in delivering an eco-friendlyeducation to the local marketplace.展开更多
基金Supported by the National Natural Science Foundation of China( No.2 0 1730 14 )
文摘We substituted several environmentally friendly catalysts which included HY and H- β zeolites, various cation-exchanged β zeolites, and solid-supported ferric chloride for conventional catalysts for the synthesis of 3-(1-cyclohexenyl)-2-butanone from the reaction of ethylidenecyclohexane with acetic anhydride at room temperature. HY zeolite was found to be the most effective for this reaction, and gave the acylated product in a 72% yield under the conditions of n (ethylidenecyclohexane)/ n (acetic anhydride)/ m (HY zeolite)=1 mmol/10 mmol/0 100 g, reaction temperature 25 ℃ and reaction time 2 h. The used HY zeolite can be recovered, regenerated and gave almost the same yield as the fresh one. The lifetime of the HY zeolite is over 80 h. The effect of different factors on the reaction has also been investigated.
文摘Bloomsbury Academic By 2025,China will have built 15 new＂super cities＂each with 25 million inhabitants.It will also have created 250＂eco-cities＂which will be clean,green,car-free,peoplefriendly and hi-tech urban centers.The urban environmental turnaround experiment may provide valuable experience for cities worldwide.Austin Williams,a correspondent of the Architectural Review to China.
文摘1.care about,care for,take care of (1)这三个动词短语均可表示"喜欢…‘关心"之意,后接n.或v.-ing形式作宾语。He cared nothing about/for skating.他对滑冰没有兴趣。In our class,we care for/about each other.
文摘1.Complete the map of each site based on what you hear on the tape. 1)based on what you hear on the tape是过去分词短语,在句子中作定语,修饰site。be based on意为"以……为根据"。This novel is based on historical facts.
文摘一、重点单词1.spread【考纲释义】vt.& vi.传播;伸展;展开【备考实例】Papermaking began in China and from here it ____ to North Africa and Europe. A.grew B.carried C.spread D.developed【考点解析】句意"
文摘January 18th,Bayer Material Science (BMS)and the Changzhou Research Institute (CRI)participated ina signing ceremony for cooperation to promote thewaterborne coatings
文摘As a chain effect of its accelerated urbanizationand industrialization, the Chinesesociety is expecting a soaring demand onhousing for years ahead. The Powder Coatingsunit of AkzoNobel China not just readsthis as a signal of enormous businessopportunities, but also an urge for takingprompt actions in delivering an eco-friendlyeducation to the local marketplace.
