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1.
以甲基丙烯酸甲酯、丙烯酸丁酯等为原料,采用乳液聚合法合成了弱溶剂墨水打印涂层用粘合剂.考察了交联剂种类及用量、致孔剂用量、单体质量比对吸墨性能及其它应用性能的影响.研究表明,当w(交联剂二乙烯基苯)=4%,w(致孔剂乙酸乙酯)=30%,m(硬单体甲基丙烯酸甲酯)∶m(软单体丙烯酸丁酯)=1∶2时,合成的粘合剂具有较好的应用性能.  相似文献   

2.
以咔唑为主要合成原料,通过N-烷基化、付克酰基化、硝化以及付克烷基化等反应合成了两个结构新颖的3,6-位不对称二取代咔唑衍生物.探讨了原料摩尔比、催化剂用量、反应温度及反应时间等因素对反应的影响,得到最佳反应条件:(1)傅克酰基化反应:n(N-乙基咔唑)∶n(三氯化铝)∶n(乙酰氯)=1∶1.2∶1.5,反应温度室温,反应时间4 h,产品收率82%;(2)硝化反应:n(N-乙基咔唑)∶n(65%硝酸)=1∶1.15,反应温度5~10℃,反应时间2 h,产品收率89%;(3)傅克烷基化反应:n(3-乙酰基-N-乙基咔唑)∶n(氯化锌)∶n(叔丁基氯)=1∶1.5∶1.5,反应温度室温,反应时间12 h,产品收率64%.所得产品结构经FTIR1、H NMR1、3C NMR、及MS表征.  相似文献   

3.
采用分散聚合法制备出粒径8.21μm,分散系数约为0.04,交联度约为12.6%的单分散聚合微球,考察了交联剂加入方式用量,加入时间及抗坏血酸用量等因素对合成聚合物PS微球粒径和分布的影响.实验结果表明,当单体St质量分数为28.8%~33.5%,引发剂用量m(AIBN)∶m(St)=0.03~0.06,稳定剂用量m(PVP)∶m(St)=0.5~0.8,采用交联剂DVB后滴入法,交联剂用量m(DVB)∶m(St)=0.02~0.08,在反应进行到6h后开始滴加DVB,2h滴加完,可合成出单分散性好、分散系数低、大粒径高交联的PS微球.  相似文献   

4.
压裂用疏水缔合型聚丙烯酰胺稠化剂的制备与表征   总被引:2,自引:0,他引:2  
采用反相乳液法、氧化还原引发体系,合成了压裂用两性聚丙烯酰胺稠化剂.应用FT-IR初步表征了产品的结构.研究发现,当引发剂质量分数为0.8%(对单体),乳化剂质量分数为10%(对油相),m(油)∶m(水)为1.4∶1.0,聚合反应温度为40℃,单体n(AM)∶n(DMC)∶n(AA)为1.0∶0.6∶0.3,制得的两性聚丙烯酰胺相对分子质量可达528万.  相似文献   

5.
以农业副产物稻壳为硅源、 硫酸铝为铝源, 通过炭化、 碱溶和水热合成工艺, 无需老化过程及添加晶种制备了洗涤助剂P型分子筛, 并考察了硅铝比、 碱度比、 反应时间和反应温度对合成分子筛的影响. 实验结果表明, 分子筛合成的最佳条件为: n(Na2O) ∶n(SiO2)=1.43, n(SiO2) ∶n(Al2O3)=4,  n(H2O) ∶n(Na2O)=18.3, 在85 ℃反应8 h. 产品的XRD和SEM表征表明, 上述条件下合成的P型分子筛产品具有较高的结晶度, 无杂相且晶粒细小, 其Ca2+交换容量可达330 mg/g.  相似文献   

6.
通过水热法合成新型Dawson结构磷钨钼杂多酸催化剂,对催化剂进行FT-IR、TG-DTA表征,并用于催化30%H2O2氧化环己酮制备己二酸.通过正交实验确定了优化工艺条件,并探讨了反应机理.结果表明,当n(环己酮)∶n(过氧化氢)∶n(草酸)∶n(催化剂)=100∶400∶1.00∶0.15,反应温度100℃,反应时间5h,进行3次平行实验,己二酸平均收率为71.6%,纯度为99.7%.经蒸发浓缩,催化体系可重复使用5次,收率为50.3%.  相似文献   

7.
考察氰酸钠合成工艺中溶剂种类、溶剂用量、原料物质的量之比、反应温度及反应时间对产品纯度和收率的影响,采用红外光谱确证产物的结构。在N,N-二基甲酰胺(DMF)和甲苯作溶剂下,n(碳酸钠)∶n(尿素)=1∶2.6,m(原料)∶m(DMF)∶m(甲苯)=1∶5∶1,反应温度140℃,反应时间13 h条件下,产品纯度可达98.7%,收率可达99.2%。  相似文献   

8.
硫酸氢钠催化合成己酸乙酯的研究   总被引:1,自引:0,他引:1  
利用硫酸氢钠作为催化剂合成了己酸乙酯,通过正交试验得出其最佳合成条件为:投料比n(己酸)∶n(乙醇)=1∶2;w(硫酸氢钠)∶w(反应物)=2:100;带水剂w(甲苯)∶w反应物=1∶4,反应时间2h,酯化率达95.0%以上.该催化剂催化效果好,无污染,易分离回收,可重复使用.  相似文献   

9.
MCM-49分子筛的合成及催化性能   总被引:2,自引:1,他引:1  
以六亚甲基亚胺(HMI)为模板剂, 采用水热合成法合成了MCM-49分子筛, 考察 了静态合成条件对合成的影响. 用XRD, IR和NH3-TPD等测试手段对合成产品的 物相和酸性进行分 析和表征, 结果表明: n(H2O)∶n(SiO2)=35~40, n(HMI)∶n( SiO2)=0.5和n(SiO2)∶n(Al2O3 )=20~35, 晶化72 h可以稳定合成出MCM-49分子筛, 合成的样品在1-丁烯骨架异构 化反应中表现出良好的催化性能.  相似文献   

10.
亲水性分子印迹纳米球的合成及药物识别与释放性能研究   总被引:1,自引:0,他引:1  
 以s-萘普生为模板分子(T),以甲基丙烯酸(MAA)为功能单体,甲基丙烯酸缩水甘油酯(GMA)为药物识别与释放的调节剂,二乙烯基苯(DVB)为交联剂,利用沉淀聚合法和环氧开环两步反应制备出亲水性的均匀球形纳米分子印迹聚合物。当n(T)∶n(MAA)∶n(GMA)∶n(DVB)=1∶4∶4∶24时制备的印迹聚合物粒径均一,单分散性好,平均粒径约832 nm,吸附实验表明该聚合物不仅可以在含水介质中对药物进行特异性识别,而且还具有良好的药物缓释性能。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

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