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861.
862.
Caiyun Lin Yuying Li Weishan Tang Shufeng Zhou Xiaoping Rao 《Molecules (Basel, Switzerland)》2021,26(21)
Supramolecular hydrogels have attracted great attention due to their special properties. In this research, bio-based supramolecular hydrogels were conveniently constructed by heating and ultrasounding two components of dehydroabietic acid with a rigid tricyclic hydrophenanthrene skeleton and morpholine. The microstructures and properties of hydrogels were investigated by DSC, rheology, SAXS, CD spectroscopy, and cryo-TEM, respectively. The critical gel concentration (CGC) of the hydrogel was 0.3 mol·L−1 and the gel temperature was 115 °C. In addition, the hydrogel showed good stability and mechanical properties according to rheology results. Cryo-TEM images reveal that the microstructure of hydrogel is fibrous meshes; its corresponding mechanism has been studied using FT-IR spectra. Additionally, oil-in-water gel emulsions were prepared by the hydrogel at a concentration above its CGC, and the oil mass fraction of the oil-in-water gel emulsions could be freely adjusted between 5% and 70%. This work provides a convenient way to prepare bio-based supramolecular hydrogels and provides a new method for the application of rosin. 相似文献
863.
溶液电导率的绝对测量方法 总被引:2,自引:0,他引:2
概括论述了三种溶液电导率绝对测量方法:基于精确测量电导池几何参数的测量方法、基于电容测量的溶液电导率测量方法和基于Van Der Pauw方法的溶液电导率测量方法。前一种方法用于许多国家的溶液电导率基准测量,后两种方法可发展为溶液电导率测量的基;住方法。 相似文献
864.
An equivalent basis of icosahedral molecules is introduced in which the basis functions can be transformed under the operations in the icosahedral group (Ih). In this equivalent basis, the irreducible representation basis (IRB) of Ih, including the double‐valued IRB of I, is deduced analytically based on the method introduced in the literature [J. Comput. Chem. 17 , 851 (1996)]. Therefore the concepts of symmetry‐matrix and symmetry‐supermatrix can be used in the single‐ and multiconfiguration self‐consistent field methods (including relativistic effects) to reduce the storage of two‐electron integrals and calculations of Fock matrix during iterations by a factor of ca. 10,000. In addition, the equivalent basis of Ih can also be used to reduce the calculations of atoms and representations of rank ≥ 2 tensors. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 77: 615–624, 2000 相似文献
865.
Yue Wu Hong Gang Zhao Xiaoping Liu Jiping Li Kaihai Yang Hong Bin He 《International journal of quantum chemistry》2000,78(4):237-244
The three evaluative methods of the moment by means of the coefficient ak of the HMO characteristic polynomial, the tree graph, and walk graph have been studied. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 78: 237–244, 2000 相似文献
866.
Computational fluid dynamics(CFD)has become a valuable tool to study the complex gas-solid hydrodynamics in the circulating fluidized bed(CFB).Based on the two fluid model(TFM)under the Eulerian-Eulerian framework and the dense discrete phase model(DDPM)under the Eulerian-Lagrangian framework,this work conducts the comparative study of the gas-solid hydrodynamics in a CFB riser by these two different models.Results show that DDPM could be used to predict gas-solid hydrodynamics in the circulating fluidized bed,and there are differences between TFM and DDPM,especially in the radial distribution profiles of solid phase.Sensitivity analysis results show that the gas-solid drag model exhibits significant effects on the results for both the two models.The specularity coefficient and the restitution coefficient in the TFM,as well as the reflection coefficient and the parcel number in the DDPM,exhibit less impact on the simulated results. 相似文献
867.
A method of multi-channel receiving for high bit rate heterodyne direct-detection optical orthogonal frequency-division-multiplexing (OOFDM) system is proposed to reduce the sampling rate demand of analog-to-digital converter (ADC). The sampling rate of ADCs can be reduced to 1/N that of the original signal bandwidth in an N-channel receiving system. Aided by a succeeding digital signal processing (DSP) at the receiver, aliasing free signal can be recovered. A back-to-back experimental result is given for a 4-channel system, based on which, a down conversion process for heterodyne can be reduced. The signal rebuilding algorithm is given and analyzed in its complexity and noise tolerance. 相似文献
868.
矩形微槽道饱和沸腾临界热流密度特性 总被引:2,自引:2,他引:2
对矩形微槽中的流动沸腾临界热流密度进行了实验研究。研究CHF随质量流速、进口过冷度和出口干度的增加而出现的变化趋势,以及槽道尺寸对CHF的影响。搭建试验平台,在不同槽道当量直径、较大范围的质量流速和不同进口过冷度条件下,获得以去离子水为工质两相沸腾传热的实验数据。由于常规尺寸槽道CHF预测关联式并不具有普遍性,所以提出了一个适用于微槽道饱和沸腾CHF的预测模型。并通过与该文以及参考文献中实验数据进行对比,验证了该模型的适用性。 相似文献
869.
增强UV-B辐射和多效唑对绿豆光合作用的影响 总被引:1,自引:1,他引:1
使用TPS-1便携式光合仪结合Farquhar和Sharkey的理论测定或计算增强UV-B辐射、多效唑(PP333)及其复合处理幼苗的相关光合指标,并同时测定核酮糖-1,5-二磷酸羧化/加氧酶(Rubisco)含量.发现UV-B辐射降低净光合速率(Pn)、气孔限制值(Ls)和气孔导度(Gs),但使胞间隙CO2浓度(Ci)增加;PP333提高Pn、Gs和Ci,却使Ls下降;与PP333处理相较,UV-B+PP333诱导Pn、Gs和Ci降低,却促进Ls增加;UV-B对Pn、叶肉细胞光合能力(Ao)、表观量子效率(AQY)、羧化效率(dPn/dCi)和Rubisco含量的降低程度大于PP333对上述指标的提高程度,亦大于PP333处理下UV-B对上述指标的抑制程度.结果表明,UV-B降低Pn的主要原因为叶肉细胞光合活性的抑制,而PP333促进Pn及PP333减轻UV-B对Pn的抑制效应主要是通过调节Gs实现的. 相似文献
870.