四氢β-咔啉类化合物的13C NMR研究

测定了四对新合成的四氢β-咔啉化合物的¹³C NMR谱,通过APT、HETCOR和HETCOLOC谱指认了所有碳的归属.所确定的化学位移规律可以用来确定它们的构型.     

α,α'-二氧代烯酮环二硫代缩酮的NMR研究

报道标题化合物的NMR谱,利用¹H,¹³C NMR和DEPT等技术确定新化合物的化学结构,并归属了所有质子和碳的化学位移.     

新型萘酰亚胺衍生物的13C NMR研究

报道了四种新的萘酰亚胺衍生物的¹³C NMR谱. 应用¹H、¹³C、DEPT、HMQC、HMBC 等谱确定了这四种化合物的分子结构,并对全部谱峰进行了归属,探讨了分子结构对¹³C NMR化学位移的影响.     

筋骨草甾酮C的谱学特征

筋骨草甾酮C是分布于植物中的植物甾酮类化合物,具有抗氧化的作用.本文标定了该化合物中所有的碳信号,并通过¹³C-¹H COSY和¹H-¹H COSY技术纠正了文献中氢信号归属的错误.     

三苯基锡苯氧乙酸酯化合物的13C NMR研究

测定了14种三苯基锡苯氧乙酸酯化合物的¹³CNMR谱,利用模型化合物对比及化学位移计算比较等方法.对全部谱线进行了归属,确定了化合物的分子结构.首次求得对苯环碳的取代基化学位移值(SCS):C_ipso=30.2,C_ortho=-13.5,C_meta=1.0,C_para=-7.5.     

原伊鲁烷型倍半萜醇芳香酸酯的碳谱研究

作者自人工发酵得到的蜜环菌Armillaria mellea (Vahl.ex Fr.) Quel.菌丝体中分离出十七个原伊鲁烷型倍半萜醇芳香酸翻,在研究这些化合物的化学结构中,对其全去偶碳谱,偏共振谱或INEPT谱,C-H COSY谱和远程C-H COSY谱进行比较仔细地分析,指定了每个化合物各碳的归属,讨论了其碳谱的特征,并指出¹³C NMR谱是对新的该类型化合物结构测定的有效方法.     

羰基化合物分子距边矢量与其13C NMR δC的关系

通过对155个羰基化合物中羰基碳原子的¹³C NMR谱与其分子距离-边数矢量(MDE)、立体效应参数(γ 效应)关系的研究，发现羰基化合物羰基碳的¹³C NMR谱化学位移可表示为：
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δ_C=a+bμ₅₁+cμ₅₂+dμ₅₃+eμ₅₄+fγ
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此式不仅在一定程度上表明了羰基化合物¹³C NMR谱化学位移与其分子结构信息之间的关系，同时也提供了一种计算羰基化合物¹³C NMR化学位移的新方法，并对解析和预测其¹³C NMR谱提供了理论依据.      

Fe(Ⅲ)对脂肪酸13C NMR信号的影响

研究了Fe (Ⅲ)对脂肪酸¹³C NMR信号的影响.结果表明,Fe (Ⅲ)对脂肪酸¹³C NMR信号的影响的机理是电子自旋弛豫对核自旋弛豫的影响;产生这种影响的必要条件是Fe (Ⅲ)与脂肪酸之间的缔合.该影响沿化学键传递并随距离的增加而迅速衰减.破坏Fe (Ⅲ)与脂肪酸之间的缔合,可使这种影响消失.利用该现象可帮助某些化合物¹³C NMR信号的归属,并可对某些分子在溶液中的状态进行研究.     

烷基极化效应与羰基13C化学位移

对羰基化合物中羰基碳的¹³C NMR化学位移与烷基（R）极化效应的内在关系 进行了研究. 结果表明：分子中R的极化效应增加使羰基碳的¹³C化学位移值升 高,其关系可表示为δ=a+b·ΣPEI(R),其中a、b为系数,PEI（R）为R极化效应指数.
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含手性轴的季戊四醇双缩醛的NMR研究

采用1D和2D梯度场NMR技术(包括1D ¹H NMR, ¹³C NMR, DEPT, 2D ¹H-¹H COSY, HSQC, HMBC),对3,3′-二（2,4-二氯苯基）-2,4,2′,4′-四氧杂螺[5.5]十一烷的4个亚甲基呈现的4组裂分峰进行了明确的归属,也对化合物中其它¹H和¹³C NMR谱信号进行了全归属,为四氧杂螺双缩醛类化合物的结构鉴定提供了充分依据.     

四氯蔗糖及其衍生物的NMR碳氢化学位移完全解析及结构研究

4,6,1′,6′-四氯蔗糖及其两个单酯化衍生物4,6,1′,6′-四氯蔗糖-3-乙酯和4,6,1′,6′-四氯蔗糖-2-乙酯是在合成三氯蔗糖的过程中得到的3种副产物，应用质谱（MS）和核磁共振（NMR）中的¹H-¹H COSY、HSQC等多种二维谱技术对它们的结构进行了研究，报道了四氯蔗糖及其两个单酯衍生物的合成及NMR碳氢化学位移完全解析，并对其氯化产物的立体化学进行了讨论.     

8-O-4′型异木脂素立体构型的测定方法

综述了关于8-O-4′型异木脂素的立体化学方面的研究. 总结了测定8-O-4′型异木脂素的相对构型和绝对构型的常用方法. ¹H NMR谱是研究C-7 和C-8间相对构型的常用方法, 若H-7的偶合常数较小，在2.7～5.0 Hz范围内，为赤式；若H-7的偶合常数较大，在6.0～8.6 Hz范围内，则为苏式. 结合NOE差谱以及CD谱的测定，或者Mosher's法，可进一步阐明其绝对构型.     

管壁厚度对紧凑型荧光灯特性的影响

研究了环境温度改变时,对两种不同管壁厚度的紧凑型荧光型灯的光学、电学特性的影响,以及不同的折叠尺寸、电特性受环境温度改变的影响;推荐了合适的电流密度(0.27A/cm²)和薄管(0.65mm)紧凑荧光灯.     

川射干中点地双梅糖苷的结构研究

采用95 %乙醇提取,硅胶柱层析,以及重结晶等方法从川射干中分离其化学成分,并通过各种光谱进行结构鉴定. 从川射干正丁醇部位分离得到一个酚二糖苷类化合物点地双梅糖苷（Tectoruside）,通过包括2D NMR在内的各种光谱首次阐明了它的结构,归属了所有碳与氢的化学位移,其结构为1-{3′-甲氧基-4′-[O-β-D-吡喃葡萄糖基(1→6)-β-D-吡喃葡萄糖基\]苯基}乙酮.     

The ρ-π Puzzle of J/φ and φ′ Decays

The recent BES Collaboration data on φ →PV, particularly the isospin violating mode φ′ → π^oω^o and finding of a finite number for B(φ′ → K^*OK^O), enable us now to deal more precisely about the challenges to theory concerning this extraordinary and remarkableso-called ρ-π puzzle of J/φ and φ′ decays. In terms of the existing data and deploying the simplest phenomenology, measurement of φ′ → π⁺π^- and whether a finite number for the K^*+K^- mode might require a significantly large accumulation of data remain interesting questions.     

Cu2S nanocrystals incorporated highly efficient non-fullerene ternary organic solar cells

Here, we report Cu₂S nanocrystals based non-fullerene ternary polymer solar cells by incorporating Cu₂S in conjugated polymer (PBDB-T: poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b′]dithiophene))-alt-(5,5-(1′,3′-di-2-thienyl-5′,7′-bis(2-ethylhexyl) benzo[1′,2′-c:4′,5′-c′]dithiophene-4,8-dione))]) and small molecule non-fullerene compound (ITIC:3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene). The devices were fabricated in inverted configuration i.e. ITO/ZnO/PBDB-T: Cu₂S NCs: ITIC/MoO₃/Ag. Effect of concentration of Cu₂S nanocrystals on the performance parameters of PBDB-T: ITIC based organic solar cells is studied. An enhancement in the power conversion efficiency from 8.24% to 9.53% is achieved for the optimum concentration of Cu₂S nanocrystals in the organic photoactive blend. The cause of improvement in the performance parameters of the device is investigated by means of the light intensity dependent electrochemical impedance spectroscopy and atomic force microscopy. It is found that the devices with Cu₂S nanocrystals have less trap-assisted recombination.     

Molecular Structures of H2X and D2X(X=0, S,Se, Te)

There are two possible configurations for H₂O, linear(D_∞h) or bent(C_2v). For a C_2v′, the three bands ν_1′ ν₂ and ν₃ should appear in both Raman and infrared. For a D_∞h. however, the ν₁, band should appear in only Raman and the ν₂ and ν₃ bands, in only infrared, that is, a principle of mutual exclusion of Raman and infrared should hold. The present author concludes that H₂X and D₂X(X=O, S, Se, Te) have a linear D_∞h. structure, since the obtained spectra show mutual exclusion of Raman and infrared.     

Microstructures of a single-crystal nickel-base superalloy after thermo-mechanical fatigue

The microstructures of a single-crystal nickel-base superalloy were observed by transmission electron microscopy (TEM) before and after thermo-mechanical fatigue. Both dislocation configurations and γ′ precipitate morphologies under in-phase (IP) testing were found to be clearly different from those under out-of-phase (OP) testing. Under IP testing, dense hexagonal dislocation networks were found on the horizontal interfaces, and irregular dislocation networks on the vertical interfaces. With decreasing mechanical strain amplitude, rafting of γ′ precipitates was more pronounced. Under OP testing, no dislocation networks were found on the γ/γ′ interfaces; also, γ′ precipitates were sheared by superlattice stacking faults, and were not clearly rafted. The characteristic dislocation networks and partials of the stacking fault are analysed and the rafting mechanism of the γ′ precipitates is discussed.     

Temperature dependence of the excitonic spectra of monolayer transition metal dichalcogenides

We theoretically study the temperature dependence of the excitonic spectra of monolayer transition metal dichalcogenides using the O′Donnell equation, \({E_g}(T) = {E_g}(0) - S\langle \hbar \omega \rangle [cloth(\frac{{\hbar \omega }}{{2{k_B}T}} - 1)]\). We develop a theoretical model for the quantitative estimation of the Huang–Rhys factor S and average phonon energy \(\langle \hbar \omega \rangle \) based on exciton coupling with longitudinal optical and acoustic phonons in the Fröhlich and deformation potential mechanisms, respectively. We present reasonable explanations for the fitted values of the Huang–Rhys factor and average phonon energy adopted in experiments. Comparison with experimental results reveals that the temperature dependence of the peak position in the excitonic spectra can be well reproduced by modulating the polarization parameter and deformation potential constant.     

棉毛橐吾根茎中3个黄酮类化合物的NMR研究

从棉毛橐吾（Ligularia vellerea）根茎中分离得到2个查尔酮和1个黄酮类化合物：3,2′, 4′-三羟基-4-甲氧基-查尔酮（1）、4,2′,4′-三羟基-查尔酮（2）和7,3′-二羟基 4′-甲氧基黄酮（3）. 应用1D和2D NMR(包括¹H-¹H COSY、HSQC和 HMBC)对这3种化合物的结构进行了分析,确认了化合物1和3中甲氧基和羟基及化合物2中羟基的连接位置,并对它们的¹H和¹³C的化学位移进行了全归属. 