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101.
Four ZnII/CdII coordination polymers (CPs) based on 2‐(4‐carboxy‐phenyl)imidazo[4, 5‐f]‐1, 10‐phenanthroline (HNCP) and different derivatives of 5‐R‐1, 3‐benzenedicarboxylate (5‐R‐1, 3‐BDC) (R = NO2, H, OH), [Zn(HNCP)(5‐NO2‐1, 3‐BDC)]n ( 1 ), [Cd(HNCP)(5‐NO2‐1, 3‐BDC)]n ( 2 ), [Zn(HNCP)(1, 3‐BDC)(H2O)2]n ( 3 ), and {[Zn(HNCP)(5‐OH‐1, 3‐BDC)(H2O) · H2O}n ( 4 ) were synthesized under hydrothermal conditions. Compounds 1 – 4 were determined by elemental analyses, IR spectroscopy, and single‐crystal and powder X‐ray diffraction. Compounds 1 and 2 are isomorphous, presenting a 4‐connected uninodal (4, 4)‐sql 2D framework with threefold interpenetration, which are further extended into the three‐dimensional (3D) supramolecular architecture through π ··· π stacking interactions between the aryl rings of 5‐NO2‐1, 3‐BDC. Compared to compound 1 , 3 is obtained by using different reaction temperatures and metal‐ligand ratios, generating a 3D framework with –ABAB– fashion via π ··· π stacking interactions. Compound 4 is a 1D chain, which is further extended into a 3D supramolecular net by hydrogen bonds and π ··· π stacking interactions. The thermogravimetric and fluorescence properties of 1 – 4 were also explored.  相似文献   
102.
采用液相色谱串联质谱法(LC/MS/MS)测定含藻水氯消毒产生7种亚硝胺类(NAms)消毒副产物(NDMA,NMEA,NDEA,NDPA,NDBA,NPyr,NPip).方法检出限分别为5.0,14,8.6,3.6,2.9,6.3和4.9 ng/L,相关系数r>0.999.除NDBA回收率(60%)较低外,其余6种亚硝胺回收率均在80%~120%之间,相对标准偏差为1.4%~12.6%.分别以藻原液和消毒后藻液配制基质标准曲线,采用其与纯水标准曲线斜率之比评估基质效应.藻原液的基质效应为0.79 ~0.94,藻液消毒后NDMA基质效应为0.36,其他亚硝胺为0.63~0.96.应用此方法检测了自来水、富营养江河水、景观水及藻类悬浮液氯消毒后的亚硝胺含量.  相似文献   
103.
With the calorimetric (adsorption heat versus coverage) curve also measured together with the adsorption isotherm, the simultaneous use of both curves showed that there were two phases of adsorption in the adsorption of methanol, dimethyl ether, ethene and propane in SAPO-34. The dual-site Langmuir equation gave good fits to the adsorption data to support the interpretation that a second (type 2) adsorption phase occurred in the high-pressure region in addition to a first (type 1) adsorption phase on the acid sites at lower pressures. Adsorption experiments and calculations using binary gas mixtures showed that due to the existence of two types of adsorption, the multicomponent Langmuir isotherm equation (Langmuir competitive adsorption model) calculated incorrect surface concentrations when the concentrations were high. In contrast, the ideal adsorbed solution theory (IAST) calculated correct surface concentrations in the adsorption of mixtures.  相似文献   
104.
Poly(1,5‐diaminoanthraquinone) is synthesized by oxidative polymerization of diaminoanthraquinone monomers and investigated as an organic host for Li‐storage reaction. Benefiting from its high density of redox‐active, Li+‐associable benzoquinone groups attached to conducting polyaniline backbones, this polymer undergoes its cathodic reaction predominately through Li+‐insertion/extraction processes, delivering a very high reversible capacity of 285 mAh g?1. In addition, the PDAQ polymer cathode exhibits an excellent rate capability (125 mAh g?1 at 800 mA g?1) and a considerable cyclability with a capacity retention of ~160 mAh g?1 over 200 cycles, possibly serving as a sustainable, high capacity Li+ host cathode for Li‐ion batteries. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 235–238  相似文献   
105.
相变材料因为其优良的热性能,被广泛应用于纺织品、航空航天、交通运输、农业、国防、建材、太阳能系统和医疗设备等领域。近年来,开发应用新型相变材料已经成为研究热点。本文首先概括介绍了相变材料发展进程,着重介绍了有机相变材料,包括它的分类、性能和应用。详细介绍了有机相变材料在纺织行业的应用,以及对调温纺织品测试手段的研究和建立的相关数学模型的建立。  相似文献   
106.
A series of adsorbents were studied for removal efficiency of carbon disulfide (CS2) under micro-oxygen conditions. It was found that activated carbon modified by Cu and cobalt sulfonated phthalocyanine (CoSPc) denoted as ACCu–CoSPc showed significantly enhanced adsorption ability. Reaction temperature was found to be a key factor for adsorption, and 20 °C seems to be optimal for CS2 removal. Samples were analyzed by N2-BET, XRD, XPS, SEM–EDS and CO2-TPD. The characterization results demonstrated that large quantities of SO4 2? anions were formed and adsorbed in the reaction process. SO2, CS2 and COS were detected in the effluent gas generated from the temperature programmed desorption of ACCu–CoSPc–CS2. Therefore, it can be concluded that ACCu–CoSPc most likely acted as a catalyst in the adsorption/oxidation process on the surface of the impregnated sample. The generated sulfide and sulfur oxide can cover the active sites of adsorbents, resulting in pronounced reduction of adsorbent activity. Finally, the exhausted ACCu–CoSPc can be regenerated by thermal desorption.  相似文献   
107.
Fluorenes are a commonly encountered structural motif in materials science, pharmaceutical chemistry, and organic synthesis. Among various strategies towards the synthesis of this unique structure, transition metal‐catalyzed functionalization has emerged as one of the most efficient methods. This Minireview presents an overview of the recent advances in this emerging area by highlighting the reactions’ specificity and applicability and, where possible, provides a mechanistic rationale.  相似文献   
108.
An unprecedented remote construction of chiral vicinal tertiary and quaternary centers by a catalytic asymmetric 1,6‐conjugate addition of prochiral carbon nucleophiles to cyclic dienones has been developed. Both 5H‐oxazol‐4‐ones and 2‐oxindoles were found to be very efficient carbon nucleophiles in this reaction at a remote position, giving products with excellent enantio‐ and diastereoselectivities (up to 99 % ee and >19:1 d.r. for 5H‐oxazol‐4‐ones and up to 97 % ee and >19:1 d.r. for 2‐oxindoles).  相似文献   
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