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141.
142.
Five new ZnII complexes, namely [Zn3(L)6] ( 1 ), [Zn2(Cl)2(L)2(py)2] ( 2 ), [Zn2(Br)2(L)2(py)2] ( 3 ), [Zn(L)2(py)] ( 4 ), and [Zn2(OAc)2(L)2(py)2] ( 5 ), were prepared by the solvothermal reaction of ZnX2 (X?=Cl?, Br?, F?, and OAc?) salts with a 8‐hydroxyquinolinate ligand (HL) that contained a trifluorophenyl group. All of the complexes were characterized by elemental analysis, IR spectroscopy, and powder and single‐crystal X‐ray crystallography. The building blocks exhibited unprecedented structural diversification and their self‐assembly afforded one mononuclear, three binuclear, and one trinuclear ZnII structures in response to different anions and solvent systems. Complexes 1 – 5 featured four types of supramolecular network controlled by non‐covalent interactions, such as π???π‐stacking, C? H???π, hydrogen‐bonding, and halogen‐related interactions. Investigation of their photoluminescence properties exhibited disparate emission wavelengths, lifetimes, and quantum yields in the solid state.  相似文献   
143.
Wang  Litao  Cheng  Jianfeng  Bao  Chenyang  Wang  Yanhui  Jiang  Qiao  Pan  Yuelong  Liu  Yu  Hong  Tao  Tuo  Xianguo  Leng  Yangchun 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2159-2167
Journal of Radioanalytical and Nuclear Chemistry - Groundwater is the most important factor contributing to the diffusion and migration of radionuclides in the repository. In this paper, the...  相似文献   
144.
Qiao  Liangzhi  Liao  Yuxin  Wang  Xiawen  Wang  Shanshan  Du  Kaifeng 《Cellulose (London, England)》2022,29(13):7263-7276
Cellulose - Cellulose microspheres are commonly chromatographic media yet seriously limited in biomacromolecules separation and purification due to the slow mass transfer kinetics resulting from...  相似文献   
145.
Catechol adsorbed on TiO2 is one of the simplest models to explore the relevant properties of dye-sensitized solar cells. However, the effects of water and defects on the electronic levels and the excitonic properties of the catechol/TiO2 interface have been rarely explored. Here, we investigate four catechol/TiO2 interfaces aiming to study the influence of coverage, water, and defects on the electronic levels and the excitonic properties of the catechol/TiO2 interface through the first-principles many-body Green's function theory. We find that the adsorption of catechol on the rutile (110) surface increases the energies of both the TiO2 valence band maximum and conduction band minimum by approximately 0.7 eV. The increasing coverage and the presence of water can reduce the optical absorption of charge-transfer excitons with maximum oscillator strength. Regarding the reduced hydroxylated TiO2 substrate, the conduction band minimum decreases greatly, resulting in a sub-bandgap of 2.51 eV. The exciton distributions in the four investigated interfaces can spread across several unit cells, especially for the hydroxylated TiO2 substrate. Although the hydroxylated TiO2 substrate leads to a lower open-circuit voltage, it may increase the separation between photogenerated electrons and holes and may therefore be beneficial for improving the photovoltaic efficiency by controlling its concentration. Our results may provide guidance for the design of highly efficient solar cells in future.  相似文献   
146.
李超  乔瑶雨  李禹红  闻静  何乃普  黎白钰 《化学进展》2021,33(11):1964-1971
金属有机框架(MOFs)具有大量的孔隙结构和活性位点,在气体吸附、催化、医疗等领域均发挥了巨大的作用。MOFs是晶体粉末,具有脆性较大、在水中易分解和不易回收等缺点,从而限制了其应用。通过MOFs与柔性高分子的复合,特别是与水凝胶的复合,极大地改善了复合材料的柔顺性、可回收和可加工性等特性,进一步拓宽了MOFs的应用领域。本文详细阐述了基于水凝胶MOFs原位生成法、MOFs /水凝胶同时生成法和水凝胶包裹MOFs法等三种不同方法制备MOFs/水凝胶复合材料的研究进展,并对上述三种制备方法的特点及其产物特征进行了总结,进一步归纳了复合材料在生物医药、催化、废水处理和气体吸附等领域的应用。最后,对MOFs/水凝胶复合材料制备方法的改进和复合材料应用前景进行了深入讨论和展望。  相似文献   
147.
The O2 adsorption and dissociation on M‐doped (M = Cu, Ag, W) Al(111) surface were studied by density functional theory. The adsorption energy of adsorbate, the average binding energy and surface energy of Al surface, and the doping energy of doping atom were calculated. All the doped atoms can be stably combined with Al atoms, while being slightly embedded in the surface to a certain depth. The TOP‐type surfaces are the most stable doped surfaces for O2 adsorption, which is related to the orbital hybridization between the adsorbate and the surface atoms, the electronegativity, and the orbital energy level of the doping atoms. Moreover, the O atoms and doping atoms contribute significantly to the density of states (DOS), especially the O‐p orbital electrons and the d orbital electrons of doping atoms. The degree of O2 dissociation is related to the doping atoms on Al surfaces, and the doping atoms actually resist the dissociation of O2. W atoms have the best resistance effect on the O2 dissociation as compared with Cu and Ag atoms, especially W‐1NN surface, which has both large barrier energy and reaction energy.  相似文献   
148.
A series of 1,5-dihydro-4H-pyrrolo[3,2-c]pyridin-4-one derivatives with 3-(4-hydroxy-2-oxo-2H-pyran-3-yl) groups were synthesized via a one-pot three-component reaction of 4-aminopyridin-2(1H)-ones, 2,2-dihydroxy-1-arylethan-1-ones, and 4-hydroxy-2H-pyran-2-ones in water. This strategy not only provides a valuable tool in the design and synthesis of new hydrogenated pyrrolo[3,2-c]pyridines but also has the advantages of inexpensive starting materials, atom and step economy, environmental friendliness, good to excellent yields, and operational simplicity. A total of 14 examples were examined to show a broad substrate scope and high yields.  相似文献   
149.
Qiao  Liangzhi  Wang  Shanshan  Wang  Tao  Yu  Shasha  Guo  Shaohui  Du  Kaifeng 《Cellulose (London, England)》2021,28(14):9323-9333
Cellulose - Dye contamination of water supplies has a serious threat to human health, prompting the development of highly effective and eco-friendly adsorbents. In this work, polyelectrolyte...  相似文献   
150.
为了有效地从生物质衍生的乙酸中获得高氢气产率,通过水热法合成了一系列的NiMnY催化剂并用于乙酸自热重整(ATR)过程中,并采用X射线衍射(XRD)、N2吸附-脱附测试、H2程序升温还原(H2-TPR)探究催化剂中的内在联系。在Ni0.39Mn0.61YO3.11±δ催化剂中,经焙烧后形成了类钙钛矿型(Ni,Mn)YO3物相;经氢气还原后,转化为含有Mn O、Y2O3和高分散Ni纳米粒子的热稳定的Ni-Mn-Y-O物种。Ni0.39Mn0.61YO3.11±δ具有高效稳定的产氢催化性能,乙酸转化率高达100%,氢气产率达到2.68 mol_(H2)·molHAc-1。  相似文献   
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