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Two new kind of energy transfer donor-acceptor dyads consisting of α-naphthoic acid moiety and 9-aminoacridine units linked by tetraethylene glycol or triethylene glycol flexible chain have been synthesized.

本工作分别用聚三乙二醇及聚四乙二醇柔性链将α-萘甲酸酯与9-氨基吖啶连接起来,合成了两种新型二元发色团分子体系,在两个体系中,选择激发α-萘甲酸酯,都可以发生从α-萘甲酸酯到9-氨基吖啶的高效率的单重态-单重态能量传递。

The mechanisms of intramolecular biaryl nonphenolic coupling were explored by reactions of different 1,4-biaryl substituted butanes with DDQ in TFA.

通过对含不同取代基的芳环化合物、1,4-二芳基丁烷链上含不同取代基化合物与DDQ在TFA中进行非酚氧化偶合和重排反应的研究,对分子内的二芳基非酚氧化偶合反应机理作了深刻的探讨。

By use of titration analysis, the thesis investigated various factors such as isocyanate, PE molecular weight, reacting substance molecular ratio, reacting temperature and time etc. influencing upon prepolymerization step. It was found that 2, 4-tolulene diisocyanate and 4, 4'diphenylmethane diisocyanate is more rapidly reacted with PE600 than HDI. With PE molecular weight increasing, the reacting temperature or time should be raised or extended relevantly. Thus PE2000+2HDI pre-polymerization should be better carried out under some catalyst, for example, Triethylene diamine , Dibutyltin dilaurate and Tin octoate were used.

首先采用滴定分析方法对WRPU预聚反应的影响因素进行了研究:芳香族二异氰酸酯TDI、MDI比脂肪族二异氰酸酯HDI反应活性高,其中TDI在反应初始阶段的反应速率比MDI快,不过随着反应的进行,MDI比TDI反应速率加快,这主要是因为TDI分子中的两个-NCO反应活性差异大所致;二元醇分子量越大,反应速度越慢;聚醚二元醇比聚酯二元醇的反应速度快;当分子量超过2000的二元醇与HDI进行预聚反应时,需借助适当的催化剂来加快反应速度,从而使预聚反应能够顺利进行,分别选择DABCO、TOA和DBDTL三种催化剂进行催化反应,发现不同的催化剂,其催化效果相差较大。

This paper discussed the synthesis of different plasticizers of DONTP by using DMT,octyl alcohol,octanol,low molecular weight emtrol and others as raw materials. And the effect of process and catalysts on plasticizers was also discussed.

以对苯二甲酸二甲酯、辛醇、丁醇等低分子质量脂肪醇为原料,采用酯交换法合成出DONTP等增塑剂品种,并就合成工艺条件、催化剂种类等因素对增塑剂性能影响进行了讨论。

The reaction of cyclic b-keto esters with CF3CO2ZnCH2I provides the corresponding ring-expanded products with the advantage of mild condition in moderate to good yields. A simple and efficient procedure has been developed for a variety of 1,3-diketones converted into the corresponding 1,4-diketones and trans-1,2-disubstituted cyclopropanols in high yields. In conclusion, this new type of organozinc reagents has been developed for many useful reaction in organic synthesis.

利用有机锌试剂所具有的双重特性,在新型的Baylis-Hillman反应中,可以直接与炔基酮和醛反应一锅制得多官能团的三取代的顺式烯;在b-酮酯化合物的扩环反应中,取得了重要进展,得到了增加一个碳的扩环产物,&一步法&合成,反应条件温和、环境友好;在1,3-二酮分子中成功地插入1个碳,合成出1,4-二酮和环丙醇,为现代有机合成提供了新的合成方法,具有良好的应用前景。

Absorption spectra indicate that there is little or no interaction between chromphores in the ground state. However, the fluorescence emission of oxadiazole and triphenylamine moieties are almost quenched, which shows that in the excited ground state there exists very effective intramolecular singlet-singlet energy transfer .

研究发现,这些多发色团化合物在基态发色团之间没有作用或作用很小,而其中噁二唑和三苯基胺单元的荧光被严重的猝灭,这说明在激发态下,萘酰亚胺发色团与噁二唑、三苯胺功能团之间发生了分子内单线态—单线态能量转移。

Absorption spectra indicate that there is little or no interaction between chromphores in the ground state. However, the fluorescence emission of oxadiazole and triphenylamine moieties are almost quenched, which shows that in the excited ground state there exists very effective intermolecular singlet-singlet energy transfer.

研究发现,这些多发色团化合物在基态发色团之间没有作用或作用很小,而其中恶二唑和三苯基胺单元的荧光被严重的猝灭,这说明在激发态下,萘酰亚胺发色团与恶二唑、三苯胺功能团之间发生了分子内单线态-单线态能量转移。

The results showed that the LUMO values are -3.19eV for organic oxadiazole,-3.16eV for macromolecular oxadiazole and -3.21eV for Poly(1,3,4-oxadiazole) and their HOMO values are all under -6.0eV, hinting that they show good hole-blocking characteristics.

利用循环伏安法测定了三种不同类型衍生物的带隙和HOMO、LUMO能级,噁二唑类小分子、大分子、聚合物衍生物的LUMO能级分别为-3.19eV、-3.16eV、-3.21eV,有利于电子的注入,三种噁二唑衍生物的HOMO能级都在-6.0eV以下,对空穴也有很好的阻挡作用。

But no electron transfer was found from the excited porphyrin moiety to the oxadiazole moiety. Moreover, cyclic voltammetric studies of the dyads 5a , 3b and 4b further indicated that electron transfer from the oxadiazole moiety to the porphyrin moiety was possible.

nm激发下不存在分子内卟啉基团向噁二唑基团的电子回传竞争;电化学性能测定进一步表明从噁二唑基团向卟啉基团的电子传递是可能的。

The mechanism of the dehydrogenation reaction of OsO〓 with methane For the reaction, OsO〓+CH〓→OOs〓+H〓, the minimum energy reaction path involves two PESs of quartet and doublet states.

因此整个反应的速率决定步骤是分子氢从二重态的亚甲基二氢化物中还原消去,能垒大约为30.4kcal/mol.c。

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