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2020 Volume 83 Issue 10
2020, 83(10): 866-874, 918
Abstract:
DNA mechanical technology has been widely concerned and deeply studied in recent years. Mechanical DNA devices have been enabled by the unique molecular structure and physical and chemical properties of DNA. More complex mechanical behavior or function can be achieved by designing more elaborate mechanisms. DNA mechanical technology has played important role in studies of the fundamental properties of the biomolecules that sense, transmit, and generate pN forces. Studies of the mechanics of these biomolecules are essential to revealing their functions. Here, we reviewed the latest progress in the study of DNA mechanical technology. First, the mechanical basis of DNA was briefly described. Especially several types of mechanical DNA devices were focused on. Finally, the challenges and prospects of DNA mechanical technology were discussed.
DNA mechanical technology has been widely concerned and deeply studied in recent years. Mechanical DNA devices have been enabled by the unique molecular structure and physical and chemical properties of DNA. More complex mechanical behavior or function can be achieved by designing more elaborate mechanisms. DNA mechanical technology has played important role in studies of the fundamental properties of the biomolecules that sense, transmit, and generate pN forces. Studies of the mechanics of these biomolecules are essential to revealing their functions. Here, we reviewed the latest progress in the study of DNA mechanical technology. First, the mechanical basis of DNA was briefly described. Especially several types of mechanical DNA devices were focused on. Finally, the challenges and prospects of DNA mechanical technology were discussed.
2020, 83(10): 875-882
Abstract:
Cells are the main tool in whole cell biocatalysis. Cell membranes has the disadvantage of resistance to mass transfer, so the efficiency of cell catalysis is much lower than that of free enzyme catalysis. Improving mass transfer to intensify the reaction process is a key issue to be solved in whole cell biocatalysis. Herein, we summarize recent progresses in this field from the perspective of process intensification, which includes improving cell membrane permeability and using microfluidic tools. Moreover, the mechanisms and characteristics of these methods are analyzed. In addition, the challenges and perspectives for further advancing whole cell biocatalysis process intensification are proposed, which provides a reference for the development in this field.
Cells are the main tool in whole cell biocatalysis. Cell membranes has the disadvantage of resistance to mass transfer, so the efficiency of cell catalysis is much lower than that of free enzyme catalysis. Improving mass transfer to intensify the reaction process is a key issue to be solved in whole cell biocatalysis. Herein, we summarize recent progresses in this field from the perspective of process intensification, which includes improving cell membrane permeability and using microfluidic tools. Moreover, the mechanisms and characteristics of these methods are analyzed. In addition, the challenges and perspectives for further advancing whole cell biocatalysis process intensification are proposed, which provides a reference for the development in this field.
The Application of Core-Shell MOFs and Their Derivatives as Anode Materials in Lithium-Ion Batteries
2020, 83(10): 883-890
Abstract:
Metal-organic frameworks (MOFs) materials are widely used in the field of electrochemical energy conversion and storage, with the advantages of large specific surface area, adjustable pore size, easy preparation, structural and functional diversity. Among them, the unique core-shell materials often show more synergy between the core and shell due to the surface modification. This article introduces the development status of core-shell MOFs as anode materials for lithium-ion batteries, and focuses on the preparation methods of their derivatives (porous carbon, metal oxides, metal sulfur/selenide, metal/metal oxides) and their applications. MOFs can produce traditional inorganic electrode materials with adjustable structure and exhibit more excellent electrochemical performance by calcining at high temperature or changing the chemical reaction conditions. Finally, the problems and challenges of core-shell MOFs as anode materials for lithium-ion battery are summarized, and possible solutions and future application prospects are proposed.
Metal-organic frameworks (MOFs) materials are widely used in the field of electrochemical energy conversion and storage, with the advantages of large specific surface area, adjustable pore size, easy preparation, structural and functional diversity. Among them, the unique core-shell materials often show more synergy between the core and shell due to the surface modification. This article introduces the development status of core-shell MOFs as anode materials for lithium-ion batteries, and focuses on the preparation methods of their derivatives (porous carbon, metal oxides, metal sulfur/selenide, metal/metal oxides) and their applications. MOFs can produce traditional inorganic electrode materials with adjustable structure and exhibit more excellent electrochemical performance by calcining at high temperature or changing the chemical reaction conditions. Finally, the problems and challenges of core-shell MOFs as anode materials for lithium-ion battery are summarized, and possible solutions and future application prospects are proposed.
2020, 83(10): 891-896, 939
Abstract:
Aqueous zinc-ion batteries (AZIBs) have been paid increasing attention by researchers because of its advantages of low cost, high safety and environmental friendliness. In recent years, vanadium-based oxides have been considered as potential cathode materials for AZIBs due to their wide variety of oxides, high theoretical capacity and excellent rate performance. In this paper, the structural characteristics and advance of vanadium-based oxides mainly encompassing V2O5 and VO2 as cathode materials for AZIBs are reviewed. The key problems faced by vanadium-based oxides in AZIBs and the corresponding solutions are highlighted. Also, the future research trends of vanadium-based oxides as zinc storage materials was prospected.
Aqueous zinc-ion batteries (AZIBs) have been paid increasing attention by researchers because of its advantages of low cost, high safety and environmental friendliness. In recent years, vanadium-based oxides have been considered as potential cathode materials for AZIBs due to their wide variety of oxides, high theoretical capacity and excellent rate performance. In this paper, the structural characteristics and advance of vanadium-based oxides mainly encompassing V2O5 and VO2 as cathode materials for AZIBs are reviewed. The key problems faced by vanadium-based oxides in AZIBs and the corresponding solutions are highlighted. Also, the future research trends of vanadium-based oxides as zinc storage materials was prospected.
2020, 83(10): 897-908
Abstract:
In recent years, Fe3S4 magnetic nanoparticles have displayed huge potential in environmental treatment, energy storage, catalysts and biomedical application etc. due to its unique physicochemical properties such as quantum size effect, electromagnetism characteristic. In this review, the methods for preparing Fe3S4 nanoparticles, mainly including precipitation method, hydrothermal method (solvothermal method), thermal decomposition method and template method, and the advantages/disadvantages of various methods are summarized. Then the application of Fe3S4 nanomaterials in environmental governance, energy storage, biomedicine, etc. are introduced. Finally, some problems in the preparation of Fe3S4 nanomaterials are analyzed, and their development direction is prospected.
In recent years, Fe3S4 magnetic nanoparticles have displayed huge potential in environmental treatment, energy storage, catalysts and biomedical application etc. due to its unique physicochemical properties such as quantum size effect, electromagnetism characteristic. In this review, the methods for preparing Fe3S4 nanoparticles, mainly including precipitation method, hydrothermal method (solvothermal method), thermal decomposition method and template method, and the advantages/disadvantages of various methods are summarized. Then the application of Fe3S4 nanomaterials in environmental governance, energy storage, biomedicine, etc. are introduced. Finally, some problems in the preparation of Fe3S4 nanomaterials are analyzed, and their development direction is prospected.
2020, 83(10): 909-918
Abstract:
Heavy metal wastewater has attracted more and more attention because of its serious environmental pollution and harm to human health. Acrylic-based polymer hydrogels, as they contain multiple functional groups and a large number of active adsorption sites, play an important role in the adsorption of heavy metals. This article mainly reviewed the research progress of acrylic-based polymer hydrogels in the treatment of heavy metal wastewater, summarized the preparation methods and classification of polyacrylic acid-based polymer hydrogels, and analyzed the existing problems of using it as adsorbent in the treatment of heavy metal wastewater. Its future application and research were also prospected in the paper.
Heavy metal wastewater has attracted more and more attention because of its serious environmental pollution and harm to human health. Acrylic-based polymer hydrogels, as they contain multiple functional groups and a large number of active adsorption sites, play an important role in the adsorption of heavy metals. This article mainly reviewed the research progress of acrylic-based polymer hydrogels in the treatment of heavy metal wastewater, summarized the preparation methods and classification of polyacrylic acid-based polymer hydrogels, and analyzed the existing problems of using it as adsorbent in the treatment of heavy metal wastewater. Its future application and research were also prospected in the paper.
2020, 83(10): 919-922
Abstract:
In this paper, the industrial technology approach of CO2 resource utilization was discussed from the source of CO2, raw material, reaction process and product property. The research results showed that it is the most feasible industrial technology to make the CO2 directly into sym-triazinetriol (C3H3N3O3) with the highest fixed amount of CO2, less process energy consumption and stable properties of reaction products. It is an environmentally friendly energy technology to generate sym-triazinetriol from fossil fuels under certain technological conditions, and utilize the energy released in the process and the remaining hydrogen as energy sources.
In this paper, the industrial technology approach of CO2 resource utilization was discussed from the source of CO2, raw material, reaction process and product property. The research results showed that it is the most feasible industrial technology to make the CO2 directly into sym-triazinetriol (C3H3N3O3) with the highest fixed amount of CO2, less process energy consumption and stable properties of reaction products. It is an environmentally friendly energy technology to generate sym-triazinetriol from fossil fuels under certain technological conditions, and utilize the energy released in the process and the remaining hydrogen as energy sources.
2020, 83(10): 923-928
Abstract:
Ascorbic acid (AA) is a significant small biomolecule involved in many biochemical processes. Profiting from the oxidizability of cobalt oxyhydroxide nanoflakes(CNFs) and strong chelating interactions between Co2+ and SCN-, a novel colorimetric assay of AA was reported based on the Co2+-mediated signal transformation. In the presence of AA, CNFs were reduced into Co2+, then strongly chelated with SCN- to form a stable blueish anion complex ([Co(NCS)4]2-), resulting in a visible absorption signal at 625nm. Under the optimal conditions, the maximum absorbance was linear with AA concentration from 0.03 to 0.45 mmol/L. The regression equation is A625nm=0.638c(mmol/L) +0.042 with a correlation coefficient of 0.993 and a limit of detection of 1.5 μmol/L (3S/N).
Ascorbic acid (AA) is a significant small biomolecule involved in many biochemical processes. Profiting from the oxidizability of cobalt oxyhydroxide nanoflakes(CNFs) and strong chelating interactions between Co2+ and SCN-, a novel colorimetric assay of AA was reported based on the Co2+-mediated signal transformation. In the presence of AA, CNFs were reduced into Co2+, then strongly chelated with SCN- to form a stable blueish anion complex ([Co(NCS)4]2-), resulting in a visible absorption signal at 625nm. Under the optimal conditions, the maximum absorbance was linear with AA concentration from 0.03 to 0.45 mmol/L. The regression equation is A625nm=0.638c(mmol/L) +0.042 with a correlation coefficient of 0.993 and a limit of detection of 1.5 μmol/L (3S/N).
2020, 83(10): 929-934
Abstract:
In this paper, d-4-terpineol (d-4-TER) and butyric acid were used as raw materials to synthesize d-4-methyl-1-(1-methylethyl)-3-cyclohexen-1-yl butanoate (d-4-T-C4) by esterification method, and the structure of the product was characterized by MS and 1H NMR. The penetration promoting activity of d-4-T-C4 on SR-FP was investigated, and its penetration mechanism was studied using infrared spectroscopy and molecular docking technology. When d-4-T-C4 was added, the accumulative 24h premeation amount (Q24h) of SR-FP was 383.5±48.75 μg·cm-2, which was 3.12 and 1.34 times of the control group and d-4-TER group, respectively. However, the promoting ability of d-4-T-C4 on S-FP and R-FP were almost identical. Mechanism research showed that d-4-T-C4 insertes into the stratum corneum lipid domain, disrupting the hydrogen bonding interaction between the drug and ceramide, increasing lipid mobility and the free energy of the drug, thereby promoting drug penetration. d-4-T-C4 had a significant enhancing effect on the permeation of SR-FP through the skin and is expected to be widely used as a new type of penetration enhancer in transdermal drug delivery system.
In this paper, d-4-terpineol (d-4-TER) and butyric acid were used as raw materials to synthesize d-4-methyl-1-(1-methylethyl)-3-cyclohexen-1-yl butanoate (d-4-T-C4) by esterification method, and the structure of the product was characterized by MS and 1H NMR. The penetration promoting activity of d-4-T-C4 on SR-FP was investigated, and its penetration mechanism was studied using infrared spectroscopy and molecular docking technology. When d-4-T-C4 was added, the accumulative 24h premeation amount (Q24h) of SR-FP was 383.5±48.75 μg·cm-2, which was 3.12 and 1.34 times of the control group and d-4-TER group, respectively. However, the promoting ability of d-4-T-C4 on S-FP and R-FP were almost identical. Mechanism research showed that d-4-T-C4 insertes into the stratum corneum lipid domain, disrupting the hydrogen bonding interaction between the drug and ceramide, increasing lipid mobility and the free energy of the drug, thereby promoting drug penetration. d-4-T-C4 had a significant enhancing effect on the permeation of SR-FP through the skin and is expected to be widely used as a new type of penetration enhancer in transdermal drug delivery system.
2020, 83(10): 935-939
Abstract:
Based on the comparative molecular field analysis(CoMFA) method, three dimensional quantitative structure-activity relationships (3D-QSAR) between the molecular structures and the in vitro anti-cancer activity (pM) of 24 pefloxacin isotriazole sulfide derivatives against human liver cancer cells (SMMC-7721) were established. Twenty compounds in the training set were served to build the predicting model, and the test set of ten compounds(containing template molecule and newly designed 5 molecules) were used to validate the model. The coefficient of the cross-validation (Rcv2) and non cross-validation (R2) for CoMFA model established in this study were 0.705 and 0.940, respectively. The results showed that the model has strong stability and good predictability. In this model, the contributions of the steric and electrostatic fields were 74.8% and 25.2%, respectively, indicating that the main factor to impact on pM was the hydrophobic factor and steric fit of substituted groups, followed by Coulomb force, hydrogen bonds and coordination of substituted groups. Base on the CoMFA contour maps, we also designed five novel molecules with satisfied prediction activity for the further experimental validation.
Based on the comparative molecular field analysis(CoMFA) method, three dimensional quantitative structure-activity relationships (3D-QSAR) between the molecular structures and the in vitro anti-cancer activity (pM) of 24 pefloxacin isotriazole sulfide derivatives against human liver cancer cells (SMMC-7721) were established. Twenty compounds in the training set were served to build the predicting model, and the test set of ten compounds(containing template molecule and newly designed 5 molecules) were used to validate the model. The coefficient of the cross-validation (Rcv2) and non cross-validation (R2) for CoMFA model established in this study were 0.705 and 0.940, respectively. The results showed that the model has strong stability and good predictability. In this model, the contributions of the steric and electrostatic fields were 74.8% and 25.2%, respectively, indicating that the main factor to impact on pM was the hydrophobic factor and steric fit of substituted groups, followed by Coulomb force, hydrogen bonds and coordination of substituted groups. Base on the CoMFA contour maps, we also designed five novel molecules with satisfied prediction activity for the further experimental validation.
2020, 83(10): 940-945
Abstract:
Phosphodiesterase 4b plays a key role in catalyzing the hydrolysis of the secondary signal messenger cyclic adenosine monophosphate (cAMP), which is able to regulate the function of airway smooth muscle, inflammatory cells and immune cells. Selective phosphodiesterase 4b (PDE4b) inhibitors received great attentions because they do not cause nausea and vomit while being used as anti-inflammatory drugs for asthma and chronic obstructive pulmonary disease (COPD). In this paper, a comparative molecular field (CoMFA) method was used to construct a reasonable three-dimensional quantitative structure-activity relationship (3D-QSAR) model for a series of pyrimidine derivatives PDE4b inhibitors. The molecular docking method was used to study the interactions between inhibitors and PDE4b. The results showed that the introduction of a five-membered cyclic hydrocarbon group with an electronegative group at the 2 position of the pyrimidine can increase the activity. Small substituent group at the 4 and 5 positions of the pyrimidine ring is suitable. The introduction of an aromatic hydrocarbon group with a hydrogen bond donor or hydrogen bond acceptor at the 6-position of pyrimidine helps to improve the activity of the compounds. This study provides theoretical guidance for the rational design of efficient PDE4b inhibitors.
Phosphodiesterase 4b plays a key role in catalyzing the hydrolysis of the secondary signal messenger cyclic adenosine monophosphate (cAMP), which is able to regulate the function of airway smooth muscle, inflammatory cells and immune cells. Selective phosphodiesterase 4b (PDE4b) inhibitors received great attentions because they do not cause nausea and vomit while being used as anti-inflammatory drugs for asthma and chronic obstructive pulmonary disease (COPD). In this paper, a comparative molecular field (CoMFA) method was used to construct a reasonable three-dimensional quantitative structure-activity relationship (3D-QSAR) model for a series of pyrimidine derivatives PDE4b inhibitors. The molecular docking method was used to study the interactions between inhibitors and PDE4b. The results showed that the introduction of a five-membered cyclic hydrocarbon group with an electronegative group at the 2 position of the pyrimidine can increase the activity. Small substituent group at the 4 and 5 positions of the pyrimidine ring is suitable. The introduction of an aromatic hydrocarbon group with a hydrogen bond donor or hydrogen bond acceptor at the 6-position of pyrimidine helps to improve the activity of the compounds. This study provides theoretical guidance for the rational design of efficient PDE4b inhibitors.
2020, 83(10): 946-950
Abstract:
3-Secondary amine substituted oxetane-3-carbonitrile derivatives (1a~1d) were synthesized by the reaction of secondary amines with oxetan-3-one and trimethylsilyl cyanide in absolute methanol without catalyst. Their structure was confirmed by 1H NMR, 13C NMR and ESI-MS. The effect of conditions on the yield of product 1a was investigated as model reaction. The optimal conditions on the reaction were as follows: the mole ratio of n (isoindoline):n (oxetan-3-one):n (trimethylsilyl cyanide)=2.0:1:2.5, absolute methanol as solvent, the reaction was at 65℃ for 6h. The product of 1a was obtained in 78.3% yield. The application of the target compound was also investigated. 2-(3-Phenyloxetan-3-yl)isoindoline and (3-(isoindolin-2-yl)oxetan-3-yl)(phenyl)methanone were obtained in a yield of 40.1% and 31.5% by the reaction of 1a and phenylmagnesium bromide in tetrahydrofuran at room temperature for 5h.
3-Secondary amine substituted oxetane-3-carbonitrile derivatives (1a~1d) were synthesized by the reaction of secondary amines with oxetan-3-one and trimethylsilyl cyanide in absolute methanol without catalyst. Their structure was confirmed by 1H NMR, 13C NMR and ESI-MS. The effect of conditions on the yield of product 1a was investigated as model reaction. The optimal conditions on the reaction were as follows: the mole ratio of n (isoindoline):n (oxetan-3-one):n (trimethylsilyl cyanide)=2.0:1:2.5, absolute methanol as solvent, the reaction was at 65℃ for 6h. The product of 1a was obtained in 78.3% yield. The application of the target compound was also investigated. 2-(3-Phenyloxetan-3-yl)isoindoline and (3-(isoindolin-2-yl)oxetan-3-yl)(phenyl)methanone were obtained in a yield of 40.1% and 31.5% by the reaction of 1a and phenylmagnesium bromide in tetrahydrofuran at room temperature for 5h.
2020, 83(10): 951-954
Abstract:
Using the Nernst equation for calculations between potential and concentration, the results of one quantity are affected by the numerical error of the other. Such effect is investigated with the propagation of error and examples. Results showed that the effect of concentration error on the calculated potential is small, whereas the effect of potential error on the calculated concentration is relatively high. This phenomenon is more significant in the case of high potentials or large number of transferred electrons in the half reaction. When concentrations are the target of calculation, high-precision potentials should be used in the Nernst equation, or the equilibrium constant is used for the calculation instead of the Nernst equation. When potentials are the target of calculation, the effect of concentration error is relatively slight, so approximate concentrations are often sufficient to yield accurate potentials, which makes approximation a convenient and effective means in such calculations.
Using the Nernst equation for calculations between potential and concentration, the results of one quantity are affected by the numerical error of the other. Such effect is investigated with the propagation of error and examples. Results showed that the effect of concentration error on the calculated potential is small, whereas the effect of potential error on the calculated concentration is relatively high. This phenomenon is more significant in the case of high potentials or large number of transferred electrons in the half reaction. When concentrations are the target of calculation, high-precision potentials should be used in the Nernst equation, or the equilibrium constant is used for the calculation instead of the Nernst equation. When potentials are the target of calculation, the effect of concentration error is relatively slight, so approximate concentrations are often sufficient to yield accurate potentials, which makes approximation a convenient and effective means in such calculations.
2020, 83(10): 955-959
Abstract:
There are a lot of basic concepts in crystal structure. It is difficult to understand and distinguish clearly without strong spatial imagination for its abstract. The two-dimensional graph is short of stereoscopic feeling and the physical model only makes one unit cell, which cannot exhibit its repetitive pattern. VESTA crystal structure software can build three-dimensional supercells according to the needs, so it can show the characteristics of crystal structure intuitively. Through several teaching examples, this paper explains how VESTA software can help students understand the basic concept of crystal structure, the relationship between structure characteristics and performance, expand the cognitive field of crystal structure, and improve learning interest and exploration ability.
There are a lot of basic concepts in crystal structure. It is difficult to understand and distinguish clearly without strong spatial imagination for its abstract. The two-dimensional graph is short of stereoscopic feeling and the physical model only makes one unit cell, which cannot exhibit its repetitive pattern. VESTA crystal structure software can build three-dimensional supercells according to the needs, so it can show the characteristics of crystal structure intuitively. Through several teaching examples, this paper explains how VESTA software can help students understand the basic concept of crystal structure, the relationship between structure characteristics and performance, expand the cognitive field of crystal structure, and improve learning interest and exploration ability.
