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对于氢原子谱线(可见区)的波长数据,能否用实验数据处理方法,合乎逻辑地导出巴尔末公式,本文给予肯定,把波长与序数关联起来,并用多项式表示,则有4个待定常量,用序数的正整数条件及曲线拟合及最小二乘法来确定它们,可得到巴尔末公式,其相关系数为1。 相似文献
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第Ⅳ副族金属的双环戊二烯基二卤化物及取代双环戊:二烯基二卤化物的13C NMR谱已有一些报道.但关于双环戊二烯基二(芳氧基)钛、锫、铪类型化合物的13C NMR谱则尚未见系统报道.我们研究其13C NMR谱,目的在于探讨第Ⅳ副族的不同金属以及芳环对位不同取代基对13C化学位移的影响.我们发现环戊二烯环的13C化学位移随金属周期数的增加而有规律地移向高场.同时,在钛、锆、铪三个系列的化合物中,不论是芳环还是环戊二烯环,其相应碳原子的13C化学位移之间存在着非常好的线性关系,相关系数等于或优于0.99. 相似文献
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本文测量了CH_3CH_2O-iPrNH=P(S)OC_6H_4R-4(R=MeO、Bu、Me、H、Cl、Br、I和NO_2)、类型化合物~1H、~(31)P和~(13)C NMR谱化学位移值。结果指出:磷-31NMR化学位移值,随R取代基拉电子能力的增加而减小,其顺序是:MeO>Me>H>Br>NO_2;而苯环质子平均化学位移值则相反,随R取代基拉电子能力的增加而增大,即NO_2>Br>H>Me>MeO;但碳—13NMR化学位移值则没有上述规律性。并根据上述现象进行了简单的讨论。 相似文献
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测定了19个2-硫代-2-(二乙基氨基)-3-取代苯甲(磺)酰基-1,3,2-氧氮磷杂环戊烷的13C NMR参数.在苯甲酰类化合物中,邻位有非氢取代基时,非环的2J(PNC)随温度而变化(0~6.1Hz),这是因羧基与苯环空间位置(构象)随温度变化所致. 相似文献
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<正> 大连钢厂是一个产品种类繁多,产品结构复杂的特殊钢厂.近年来,随着国民经济的调整,产品结构发生了大幅度的变化.另一方面,部份产品降价,原材料涨价,能源(主要是电力)不足等原因对该厂生产有很大的影响,使得经济效益明显下降.于是,产生了如下的有待解决的问题:在一定的能源、一定的原材料供应、一定的设备能力、一定的人力等情况下,如何安排产品的品种及产量,使总的利润最高.我们把这个问题称为产品结构优化设计问题. 相似文献
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The five-coordinate bicycloazastannoxides (1—6) in the presence of Et_3N has been investigated by~1H NMR spectrograph. It has been found that the deuterium exchange of αCH of five-coordinate bicycloazastannoxides with CD_3OD takes place, which is catalyzed by Et_3N. In the presence of Et_3N (2μL), the apparent rate constants (k_(obs)) for the deuterium exchange in CD_3OD is determined by~1H NMR method, and the value of k_(obs) is in the range of (2.05--10.8)×10~(-4) s~(-1). The effect of the substitutes on the rates and the kinetic mechanism are discussed. 相似文献
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In this paper the reaction of substituted β-nitrostyrene with O,O-dialkyl phosphite under cocatalysis of trimethylsilyl chloride (TMS-C1) and triethylamine (or other acidbinding agent) has been first studied and the new cyclization reaction leading to the formation of product Ⅱ, as a new class of derivatives of 1-hydroxyindoles, difficultly accessible or inaccessible with usual methods has been observed. In the related reaction it is surprising that when the Arbuzov rearrangement occurs under mild conditions, the addition, reduction and cyclization as a one-pot reaction take place simultaneously with the formation of products Ⅰ, Ⅱ, Ⅲ. By controlling the reaction conditions the products were formed almost in specificity, and thus the most interesting cyclic products Ⅱ_(a-h) containing phosphorus-carbon bond were obtained. Their structures were confirmed by elemental analysis, IR, ~1H or ~(31)p NMR and MS spectra. The crystal structure of representative compound Ⅱ_h was determined by X-ray diffract 相似文献