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2017 Volume 80 Issue 12
2017, 80(12): 1083-1092
Abstract:
The natural nacre possesses organic-inorganic hierarchical layered structure and abundant synergistic interface interactions resulting in extraordinary mechanical properties. This layered architecture is built by the aragonite platelets which are glued by the biopolymer with a volume fraction of 5%. Inspired by the relevance between the microstructure and properties of nacre, various building blocks such as nanoclay, carbon nanotube and graphene oxide can be used to construct nacre-like layered structure. Besides, applying multiple interface interactions, synergistic effect from interface interactions as well as building blocks can be achieved leading to high-performance polymer nanocomposites. The bioinspired strategy to fabricate polymer nanocomposites opens up a new avenue for future research work and broadens the application of polymer nanocomposites.
The natural nacre possesses organic-inorganic hierarchical layered structure and abundant synergistic interface interactions resulting in extraordinary mechanical properties. This layered architecture is built by the aragonite platelets which are glued by the biopolymer with a volume fraction of 5%. Inspired by the relevance between the microstructure and properties of nacre, various building blocks such as nanoclay, carbon nanotube and graphene oxide can be used to construct nacre-like layered structure. Besides, applying multiple interface interactions, synergistic effect from interface interactions as well as building blocks can be achieved leading to high-performance polymer nanocomposites. The bioinspired strategy to fabricate polymer nanocomposites opens up a new avenue for future research work and broadens the application of polymer nanocomposites.
2017, 80(12): 1093-1103
Abstract:
Crystal structure and surface characteristics of transition metal oxide Co3O4 are closely related to its morphology, size and microstructure. In this paper, different morphology Co3O4 nanomaterial could be divided into several dimensions through scale, including 0D of nanospheres, cubes, polyhedral, 1D of nanowires, nanorods, nanotubes, nanocolumns and others, 2D of nanometer film, nano flakes and 3D of microscale superstructure constituted by nano-element such as urchin, micron ball etc. We discussed the influencing factors in formation of morphology, focused on the hydrothermal synthesis process and summarized the possible mechanism, to facilitate the deeply understanding of preparation of different dimension materials. Accordingly, it would provide a guidance for the synthesis of materials with specific dimension and morphology.
Crystal structure and surface characteristics of transition metal oxide Co3O4 are closely related to its morphology, size and microstructure. In this paper, different morphology Co3O4 nanomaterial could be divided into several dimensions through scale, including 0D of nanospheres, cubes, polyhedral, 1D of nanowires, nanorods, nanotubes, nanocolumns and others, 2D of nanometer film, nano flakes and 3D of microscale superstructure constituted by nano-element such as urchin, micron ball etc. We discussed the influencing factors in formation of morphology, focused on the hydrothermal synthesis process and summarized the possible mechanism, to facilitate the deeply understanding of preparation of different dimension materials. Accordingly, it would provide a guidance for the synthesis of materials with specific dimension and morphology.
2017, 80(12): 1104-1109
Abstract:
The development of modern analytical science has set a higher requirement for the sensitivity, selectivity and response speed of analytical methods. The detection and control of target molecules at the single molecule level is a challenging field that chemists have long dreamed of, and also a frontier for the development of analytical science in recent years. One of the challenges for direct analysis of single molecule by electrochemical methods is that the current caused by electron exchange of a single molecule during the redox process is too small to be detected by modern instruments. The direct electrochemical single-molecule analysis can be achieved through current amplification from massive repeat of electron exchange process on the electrode surface during redox reaction. This review summarized and compared the recent techniques and equipments for direct detection of single molecule electrochemically through amplification cycle. The future direction of development of single molecule electrochemistry was prospected too.
The development of modern analytical science has set a higher requirement for the sensitivity, selectivity and response speed of analytical methods. The detection and control of target molecules at the single molecule level is a challenging field that chemists have long dreamed of, and also a frontier for the development of analytical science in recent years. One of the challenges for direct analysis of single molecule by electrochemical methods is that the current caused by electron exchange of a single molecule during the redox process is too small to be detected by modern instruments. The direct electrochemical single-molecule analysis can be achieved through current amplification from massive repeat of electron exchange process on the electrode surface during redox reaction. This review summarized and compared the recent techniques and equipments for direct detection of single molecule electrochemically through amplification cycle. The future direction of development of single molecule electrochemistry was prospected too.
2017, 80(12): 1110-1115
Abstract:
In-situ chlorinating graft copolymerization is a new method of modified polymer based on free radical reaction. The properties of polymer modified by this method are improved obviously, and the characteristics of weak influence and strong response are shown. In this paper, the process and mechanism of in-situ chlorinating graft reaction are briefly introduced, and the structural characteristics of in-situ graft products are analyzed, also the relationship between the structure and performance of the graft copolymers is summarized. The different uses of various grafting products, such as thermoplastic elastomers, wood adhesive, toughening modifier, film coating and so on are introduced in detail. The application and future development trend of in-situ chlorinating grafting are prospected.
In-situ chlorinating graft copolymerization is a new method of modified polymer based on free radical reaction. The properties of polymer modified by this method are improved obviously, and the characteristics of weak influence and strong response are shown. In this paper, the process and mechanism of in-situ chlorinating graft reaction are briefly introduced, and the structural characteristics of in-situ graft products are analyzed, also the relationship between the structure and performance of the graft copolymers is summarized. The different uses of various grafting products, such as thermoplastic elastomers, wood adhesive, toughening modifier, film coating and so on are introduced in detail. The application and future development trend of in-situ chlorinating grafting are prospected.
2017, 80(12): 1116-1122
Abstract:
The problem of global soil contamination has become increasingly serious. Surfactant foam technology was paid much attention because of foam flow in porous media is controlled mainly by the injection pressure instead of gravity, thus avoiding the expanding of contaminated area. This paper gives a comprehensive overview of surfactant foam technology, and describes the general procedure of foam washing, its advantages and limitations, and analyzes the major factors that impact the efficiency and cost of this treatment technology.
The problem of global soil contamination has become increasingly serious. Surfactant foam technology was paid much attention because of foam flow in porous media is controlled mainly by the injection pressure instead of gravity, thus avoiding the expanding of contaminated area. This paper gives a comprehensive overview of surfactant foam technology, and describes the general procedure of foam washing, its advantages and limitations, and analyzes the major factors that impact the efficiency and cost of this treatment technology.
2017, 80(12): 1123-1127
Abstract:
Cobalt incorporated manganese octahedral molecular sieves (OMS-2) were synthesized using a one-step hydrothermal method with the mixture of KMnO4, MnSO4, Co (NO3)2·6H2O and H2SO4 as precursors. The structure, morphology, textural properties, redox properties and the surface hydrophobicity of the synthesized Co doped K-OMS-2 were measured by XRD, FT-IR, SEM, N2 sorption, H2-TPR and XPS. The results showed that the incorporation of Co didn't change or destroy the crystal structure of OMS-2. Depending on the extent of Co incorporation, their morphology changed from nanorods into nanofibers. Moreover, the incorporation of Co into OMS-2 structure increased the activity of active oxygen species, and improved their catalytic performance.
Cobalt incorporated manganese octahedral molecular sieves (OMS-2) were synthesized using a one-step hydrothermal method with the mixture of KMnO4, MnSO4, Co (NO3)2·6H2O and H2SO4 as precursors. The structure, morphology, textural properties, redox properties and the surface hydrophobicity of the synthesized Co doped K-OMS-2 were measured by XRD, FT-IR, SEM, N2 sorption, H2-TPR and XPS. The results showed that the incorporation of Co didn't change or destroy the crystal structure of OMS-2. Depending on the extent of Co incorporation, their morphology changed from nanorods into nanofibers. Moreover, the incorporation of Co into OMS-2 structure increased the activity of active oxygen species, and improved their catalytic performance.
2017, 80(12): 1128-1132
Abstract:
The reaction mechanism of La-catalyzed C2H4 dehydrogenation was studied on doublet and quartet potential energy surface in the gas phase by density functional theory B3LYP method. The geometries of all species were fully optimized. The transition states of the reaction were confirmed by the vibration frequency calculation and the intrinsic reaction coordinate (IRC) analysis. The bonding properties of the species involved in the reaction were discussed by AIM (atoms in molecules) theory and NBO (natural bond oribtal) analysis methods. 2IM1 and 2IM3 were analyzed by density of states (DOS). The results showed that there are two possible paths for the reaction of La and C2H4. The reactions are carried out on the double potential surface and both are exothermic. The bonding analysis indicated that the interaction is a covalent character between the La and C2H4.
The reaction mechanism of La-catalyzed C2H4 dehydrogenation was studied on doublet and quartet potential energy surface in the gas phase by density functional theory B3LYP method. The geometries of all species were fully optimized. The transition states of the reaction were confirmed by the vibration frequency calculation and the intrinsic reaction coordinate (IRC) analysis. The bonding properties of the species involved in the reaction were discussed by AIM (atoms in molecules) theory and NBO (natural bond oribtal) analysis methods. 2IM1 and 2IM3 were analyzed by density of states (DOS). The results showed that there are two possible paths for the reaction of La and C2H4. The reactions are carried out on the double potential surface and both are exothermic. The bonding analysis indicated that the interaction is a covalent character between the La and C2H4.
2017, 80(12): 1133-1137, 1147
Abstract:
Eight benzisothiazolin-3-one derivatives were synthesized through reaction of alkyl alcohol with 1, 2-benzisothiazol-2(3H)-one. The bioassay results showed that all compounds (2a~2h, 2mg/L) possess good anti-algae activities. The molecular models were constructed by software Chemoffice 2010, and the geometric configuration was optimized by employing semiempirical quantum chemical method (AM1). In this way, quantum chemistry and physical chemistry parameters was calculated. The primary study of quantitative structure activity relationship showed the anti-algae activities is related to LogP, and the relation model was established.
Eight benzisothiazolin-3-one derivatives were synthesized through reaction of alkyl alcohol with 1, 2-benzisothiazol-2(3H)-one. The bioassay results showed that all compounds (2a~2h, 2mg/L) possess good anti-algae activities. The molecular models were constructed by software Chemoffice 2010, and the geometric configuration was optimized by employing semiempirical quantum chemical method (AM1). In this way, quantum chemistry and physical chemistry parameters was calculated. The primary study of quantitative structure activity relationship showed the anti-algae activities is related to LogP, and the relation model was established.
2017, 80(12): 1138-1142
Abstract:
With carbazole as raw material, the intermediate N-ethyl-3, 6-diaminocarbazole was synthesized through N-alkyl substitution, nitration and reduction reaction successively. Then a novel bis-Schiff base N-ethyl-3, 6-bis(2-furalideneimino)carbazole was synthesized from 2-furaldehyde and N-ethyl-3, 6-diaminocarbazole with a yield of 72.36%. Its structure was characterized by elemental analysis, FTIR, UV-Vis, 1H NMR and EIS-MS. Solution fluorescence, solid fluorescence spectroscopy, cyclic voltammetry (CV) and TG-DTA thermal analysis were used to study its optical properties, electrochemical properties and thermal stability. The results showed that the target compound has a strong and wide UV absorption band from 200nm to 400nm in the dilute solution of DMF, and a deep blue fluorescence emission peak at 446nm excited by 365nm. Solid fluorescence spectroscopy indicated that the Schiff base has an emission peak at 467nm, with a 21nm red shift compared to the solution fluorescence. The optical band gap (Eg), ionization potential (Ip) and electron affinity (EA) of the target compound are 2.19, 4.99 and 2.80 eV, respectively, calculated from UV-Vis and CV test, which indicated that it has excellent hole and electron transporting performance. TG-DTA analysis showed that the target compound possess good thermal stability. This compound has potential applications in organic luminescence, hole injection and transport materials and electron transport materials.
With carbazole as raw material, the intermediate N-ethyl-3, 6-diaminocarbazole was synthesized through N-alkyl substitution, nitration and reduction reaction successively. Then a novel bis-Schiff base N-ethyl-3, 6-bis(2-furalideneimino)carbazole was synthesized from 2-furaldehyde and N-ethyl-3, 6-diaminocarbazole with a yield of 72.36%. Its structure was characterized by elemental analysis, FTIR, UV-Vis, 1H NMR and EIS-MS. Solution fluorescence, solid fluorescence spectroscopy, cyclic voltammetry (CV) and TG-DTA thermal analysis were used to study its optical properties, electrochemical properties and thermal stability. The results showed that the target compound has a strong and wide UV absorption band from 200nm to 400nm in the dilute solution of DMF, and a deep blue fluorescence emission peak at 446nm excited by 365nm. Solid fluorescence spectroscopy indicated that the Schiff base has an emission peak at 467nm, with a 21nm red shift compared to the solution fluorescence. The optical band gap (Eg), ionization potential (Ip) and electron affinity (EA) of the target compound are 2.19, 4.99 and 2.80 eV, respectively, calculated from UV-Vis and CV test, which indicated that it has excellent hole and electron transporting performance. TG-DTA analysis showed that the target compound possess good thermal stability. This compound has potential applications in organic luminescence, hole injection and transport materials and electron transport materials.
2017, 80(12): 1143-1147
Abstract:
In this paper, the reaction conditions for the oxidation of aldehydes with sodium chlorite and hydrogen peroxide in neutral environment were optimized. The effects of solvent, amounts of sodium chlorite and hydrogen peroxide and reaction temperature on the yield of acids were investigated by orthogonal experimental design. The optimum conditions were as follows:ethanol as solvent, the molar ratio of sodium chlorite, hydrogen peroxide and aldehyde was 1.1:2:1. The adaptability of aldehydes was verified, and the industrial applicability was demonstrated by amplification experiments. It was proved that the method has the characteristics of high yield, simple post-processing, green by-products without pollution, etc.
In this paper, the reaction conditions for the oxidation of aldehydes with sodium chlorite and hydrogen peroxide in neutral environment were optimized. The effects of solvent, amounts of sodium chlorite and hydrogen peroxide and reaction temperature on the yield of acids were investigated by orthogonal experimental design. The optimum conditions were as follows:ethanol as solvent, the molar ratio of sodium chlorite, hydrogen peroxide and aldehyde was 1.1:2:1. The adaptability of aldehydes was verified, and the industrial applicability was demonstrated by amplification experiments. It was proved that the method has the characteristics of high yield, simple post-processing, green by-products without pollution, etc.
2017, 80(12): 1148-1151, 1127
Abstract:
A new strategy was developed to synthesize a series of homocamptothecin compounds starting from t-butyl bromoacetate. This way is quite straightforward and simple and the gross yield makes a great improvement without the use of the reported phosphate or other traditional protecting groups. It enhances the solubility of each camptothecin derivative, accelerates the reaction to completion and simplifies the workup and purification procedures. As a result, a lot of amides could be obtained conveniently.
A new strategy was developed to synthesize a series of homocamptothecin compounds starting from t-butyl bromoacetate. This way is quite straightforward and simple and the gross yield makes a great improvement without the use of the reported phosphate or other traditional protecting groups. It enhances the solubility of each camptothecin derivative, accelerates the reaction to completion and simplifies the workup and purification procedures. As a result, a lot of amides could be obtained conveniently.
2017, 80(12): 1152-1155, 1127
Abstract:
We developed the cyclization reactions of α-diaryl methyl-β-ketothioesters and hydrazine for the synthesis of functionalized 5-hydroxy pyrazolyl-containing triarylmethanes. The cyclization reactions of α-diaryl methyl-β-ketothioesters and hydrazine were performed in refluxing EtOH, affording functionalized 5-hydroxy pyrazolyl-containing triarylmethanes in excellent yield. Mild reaction conditions, easy work-up procedure, and excellent yields are some notable advantages of this method.
We developed the cyclization reactions of α-diaryl methyl-β-ketothioesters and hydrazine for the synthesis of functionalized 5-hydroxy pyrazolyl-containing triarylmethanes. The cyclization reactions of α-diaryl methyl-β-ketothioesters and hydrazine were performed in refluxing EtOH, affording functionalized 5-hydroxy pyrazolyl-containing triarylmethanes in excellent yield. Mild reaction conditions, easy work-up procedure, and excellent yields are some notable advantages of this method.
2017, 80(12): 1156-1159
Abstract:
Seven novel penta-1, 4-diene-3-one oxime ether derivatives were synthesized by converting carbonyl groups in the 1, 4-pentadien-3-ones to an oxime ether groups, and their structures were confirmed by IR, 1H NMR, 13C NMR and ESI-MS. Antiviral bioassays at the concentration of 500mg/L indicated that compounds 4c, 4f, and 4g exhibite better curative activity against tobacco mosaic virus (TMV) (49.6%, 53.6% and 47.4%, respectively) than ribavirin (45.2%). The protective activities of compounds 4b, 4c, 4f and 4g against TMV are 57.2%, 58.4%, 58.9% and 59.0% respectively, which were lower than that of ribavirin (61.8%). The inactivition activities of compounds 4a, 4b, 4c and 4g against TMV are 95.5%, 92.6%, 95.0% and 89.5% respectively, which are superior to that of ribavirin (87.9%). These results indicated that penta-1, 4-diene-3-one oxime ether derivatives have good inhibitory effect against plant virus, and that some compounds with potent anti-plant viral activities can be obtained after appropriate modifications on structures of penta-1, 4-diene-3-one oxime ethers.
Seven novel penta-1, 4-diene-3-one oxime ether derivatives were synthesized by converting carbonyl groups in the 1, 4-pentadien-3-ones to an oxime ether groups, and their structures were confirmed by IR, 1H NMR, 13C NMR and ESI-MS. Antiviral bioassays at the concentration of 500mg/L indicated that compounds 4c, 4f, and 4g exhibite better curative activity against tobacco mosaic virus (TMV) (49.6%, 53.6% and 47.4%, respectively) than ribavirin (45.2%). The protective activities of compounds 4b, 4c, 4f and 4g against TMV are 57.2%, 58.4%, 58.9% and 59.0% respectively, which were lower than that of ribavirin (61.8%). The inactivition activities of compounds 4a, 4b, 4c and 4g against TMV are 95.5%, 92.6%, 95.0% and 89.5% respectively, which are superior to that of ribavirin (87.9%). These results indicated that penta-1, 4-diene-3-one oxime ether derivatives have good inhibitory effect against plant virus, and that some compounds with potent anti-plant viral activities can be obtained after appropriate modifications on structures of penta-1, 4-diene-3-one oxime ethers.
2017, 80(12): 1160-1171, 1175
Abstract:
Flat band potential (Efb) is an important concept for the system of semiconductor/electrolyte solution. It is a potential when the band is at flat state. It is special characteristics to semiconductors and it can be measured by experiments such as Mott-Schottky curve and the measurement the relationship of photocurrent and applied potentials. Besides, the semiconductor type and its carrier density can be induced from the measurement of Efb. The band structure including the conductive or valence band position of semiconductor can be obtained from Efb. This is important for the photocatalysis and photoelectrochemical process of semiconductors, which are related to the applications of solar energy. In this paper, energy band bending of semiconductor and its influence factors are analyzed in detail. It is proposed that the Fermi energy is bended in the interface of semiconductors. Furthermore, the meaning, measurements and applications of Efb are summarized in order to help the students to understand and use it.
Flat band potential (Efb) is an important concept for the system of semiconductor/electrolyte solution. It is a potential when the band is at flat state. It is special characteristics to semiconductors and it can be measured by experiments such as Mott-Schottky curve and the measurement the relationship of photocurrent and applied potentials. Besides, the semiconductor type and its carrier density can be induced from the measurement of Efb. The band structure including the conductive or valence band position of semiconductor can be obtained from Efb. This is important for the photocatalysis and photoelectrochemical process of semiconductors, which are related to the applications of solar energy. In this paper, energy band bending of semiconductor and its influence factors are analyzed in detail. It is proposed that the Fermi energy is bended in the interface of semiconductors. Furthermore, the meaning, measurements and applications of Efb are summarized in order to help the students to understand and use it.
