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2020 Volume 83 Issue 11
2020, 83(11): 962-969
Abstract:
In order to solve the problems of energy shortage and environmental pollution, the research of solar cells has attracted extensive scientific attention. Over the past decade, perovskite solar cells (PSCs) have been developing rapidly, gradually becoming one of the most powerful competitors for commercial silicon-based solar cells. However, the inevitable formation of inherent crystallographic defects during the low-temperature solution process severely limits the improvement of the efficiency and stability of PSCs. Porphyrin/phthalocyanine metal complexes with the excellent stability and photovoltaic properties have been considered for improving the efficiency and long-term stability of cells by using porphyrin/phthalocyanine complexes to passivate defects on the surface and grain boundaries of perovskite films. In this review, we summarize the research progress of highly efficient and stable perovskite solar cells using porphyrin/phthalocyanine metal complexes to modify the perovskite films. Meanwhile, the existent problem and future development of PSCs with porphyrin/phthalocyanine complexes are discussed as well.
In order to solve the problems of energy shortage and environmental pollution, the research of solar cells has attracted extensive scientific attention. Over the past decade, perovskite solar cells (PSCs) have been developing rapidly, gradually becoming one of the most powerful competitors for commercial silicon-based solar cells. However, the inevitable formation of inherent crystallographic defects during the low-temperature solution process severely limits the improvement of the efficiency and stability of PSCs. Porphyrin/phthalocyanine metal complexes with the excellent stability and photovoltaic properties have been considered for improving the efficiency and long-term stability of cells by using porphyrin/phthalocyanine complexes to passivate defects on the surface and grain boundaries of perovskite films. In this review, we summarize the research progress of highly efficient and stable perovskite solar cells using porphyrin/phthalocyanine metal complexes to modify the perovskite films. Meanwhile, the existent problem and future development of PSCs with porphyrin/phthalocyanine complexes are discussed as well.
2020, 83(11): 970-976
Abstract:
The unique physiological and pharmacological activity of aza-heterocyclic compounds has aroused the interest of researchers. In recent years, many synthetic methods for the synthesis of aza-heterocyclic compounds have been reported. Among them, selenium-π-acid catalysis has attracted extensive attention due to mild reaction conditions, simple operation, and good regioselectivity and functional group compatibility. This short review convers the progress in the synthesis of aza-heterocyclic compounds such as indoles, pyrrolidines, dihydroquinolizidines, oxazoles, pyrazolo quinazolinones, isoquinolines, and 2-imidazolidone derivatives by selenium-π-acid catalysis.
The unique physiological and pharmacological activity of aza-heterocyclic compounds has aroused the interest of researchers. In recent years, many synthetic methods for the synthesis of aza-heterocyclic compounds have been reported. Among them, selenium-π-acid catalysis has attracted extensive attention due to mild reaction conditions, simple operation, and good regioselectivity and functional group compatibility. This short review convers the progress in the synthesis of aza-heterocyclic compounds such as indoles, pyrrolidines, dihydroquinolizidines, oxazoles, pyrazolo quinazolinones, isoquinolines, and 2-imidazolidone derivatives by selenium-π-acid catalysis.
2020, 83(11): 977-985
Abstract:
Nucleic acid aptamers are oligonucleotide fragments obtained from nucleic acid molecule libraries using in vitro screening technology, namely exponentially enriched ligand system evolution technology (SELEX). They have high specificities and affinities to the targets. The biosensing research using the aptamer as the recognition unit and the in vivo and in vitro imaging research of the aptamer coupling imaging reagents have great application prospects in clinical diagnosis. In addition, aptamers targeting cancer cells or tissues have fewer side effects than traditional chemotherapeutics, and they also have great application prospects in the clinic. This article reviews the current research progress of aptamers in cancer diagnosis and targeted therapy, and analyzes the current problems and challenges.
Nucleic acid aptamers are oligonucleotide fragments obtained from nucleic acid molecule libraries using in vitro screening technology, namely exponentially enriched ligand system evolution technology (SELEX). They have high specificities and affinities to the targets. The biosensing research using the aptamer as the recognition unit and the in vivo and in vitro imaging research of the aptamer coupling imaging reagents have great application prospects in clinical diagnosis. In addition, aptamers targeting cancer cells or tissues have fewer side effects than traditional chemotherapeutics, and they also have great application prospects in the clinic. This article reviews the current research progress of aptamers in cancer diagnosis and targeted therapy, and analyzes the current problems and challenges.
2020, 83(11): 986-996
Abstract:
The insect ionotropic γ-amino-butyric acid (GABA) receptors are an important class of insecticide targets, and isoxazoline analogues are a novel type of insecticides/parasiticides that acted on this target. Since the first isoxazoline parasiticide fluralaner has been identified, novel isoxazolines such as afoxalaner, sarolaner, lotilaner, and fluxametamide have been successively reported based on their effective insecticidal activity and excellent safety. In this paper, we mainly reviewed the latest research progress in the field of isoxazoline insecticides, especially focusing on their chemical structures, insecticidal activities, mechanisms of action, biological metabolisms, and safeties. Moreover, the limitations of the application of isoxazoline insecticides/parasiticides were discussed. Finally, the application prospects and development trends of these isoxazolines in the prevention and management of agricultural pests and diseases were also pointed out.
The insect ionotropic γ-amino-butyric acid (GABA) receptors are an important class of insecticide targets, and isoxazoline analogues are a novel type of insecticides/parasiticides that acted on this target. Since the first isoxazoline parasiticide fluralaner has been identified, novel isoxazolines such as afoxalaner, sarolaner, lotilaner, and fluxametamide have been successively reported based on their effective insecticidal activity and excellent safety. In this paper, we mainly reviewed the latest research progress in the field of isoxazoline insecticides, especially focusing on their chemical structures, insecticidal activities, mechanisms of action, biological metabolisms, and safeties. Moreover, the limitations of the application of isoxazoline insecticides/parasiticides were discussed. Finally, the application prospects and development trends of these isoxazolines in the prevention and management of agricultural pests and diseases were also pointed out.
2020, 83(11): 997-1006
Abstract:
Collagen is the main structural protein of the extracellular matrix, and is found throughout the bodies of all kinds of animals. However, natural collagen has unevenness fibers, poor mechanical properties, which limits its industrial applications. Finding a way to produce a thermostable protein that shares the good properties of collagen is an important issue. Electrostatic spinning technology is a new kind of nano-material manufacturing technology. It is used to produce collagen-based nanofiber materials with different structures and properties. The prepared nanofiber material exhibits excellent characteristics such as low density and high elasticity, and is expected to be widely used in tissue engineering, medicine, chemical carrier and other fields. This paper discusses the progress in collagen electrospinning technology with respect to single static spinning of collagen and its influencing factors, collagen synthesis electrostatic spinning and its influencing factors, and applications of collagen electrospinning. The existing problems and directions for development are also discussed so as to provide theoretical guidance and technical support for the use of collagen.
Collagen is the main structural protein of the extracellular matrix, and is found throughout the bodies of all kinds of animals. However, natural collagen has unevenness fibers, poor mechanical properties, which limits its industrial applications. Finding a way to produce a thermostable protein that shares the good properties of collagen is an important issue. Electrostatic spinning technology is a new kind of nano-material manufacturing technology. It is used to produce collagen-based nanofiber materials with different structures and properties. The prepared nanofiber material exhibits excellent characteristics such as low density and high elasticity, and is expected to be widely used in tissue engineering, medicine, chemical carrier and other fields. This paper discusses the progress in collagen electrospinning technology with respect to single static spinning of collagen and its influencing factors, collagen synthesis electrostatic spinning and its influencing factors, and applications of collagen electrospinning. The existing problems and directions for development are also discussed so as to provide theoretical guidance and technical support for the use of collagen.
2020, 83(11): 1007-1013
Abstract:
Highly crystalline organic semiconductors with close molecular stacking could hold high charge mobility but low solubility in common organic solvents, limiting their solution processability for organic optoelectronics. Herein, a methyl-decorated high-crystalline squaraine dye (DM-SQ) is synthesized, and a highly crystalline thin film is solution-deposited using trifluoroacetic acid (TFA) as solvent. The resultant film shows a higher hole mobility as compared with that of the vacuum-deposited film (5.28×10-4 vs. 7.53×10-5 cm2·V-1·s-1). With DM-SQ as donor and PC61BM (phenyl-C61-butyric acid methyl ester) as acceptor, the solution-processed planar heterojunction solar cells exhibit an average power conversion efficiency of 6.08±0.19%, higher than 3.56±0.22% for the vacuum-deposited devices.
Highly crystalline organic semiconductors with close molecular stacking could hold high charge mobility but low solubility in common organic solvents, limiting their solution processability for organic optoelectronics. Herein, a methyl-decorated high-crystalline squaraine dye (DM-SQ) is synthesized, and a highly crystalline thin film is solution-deposited using trifluoroacetic acid (TFA) as solvent. The resultant film shows a higher hole mobility as compared with that of the vacuum-deposited film (5.28×10-4 vs. 7.53×10-5 cm2·V-1·s-1). With DM-SQ as donor and PC61BM (phenyl-C61-butyric acid methyl ester) as acceptor, the solution-processed planar heterojunction solar cells exhibit an average power conversion efficiency of 6.08±0.19%, higher than 3.56±0.22% for the vacuum-deposited devices.
2020, 83(11): 1014-1018
Abstract:
Catalytic formic acid decomposition to hydrogen is an important route for hydrogen storage and hydrogen energy utilization. Dendritic ionic polymer microspheres were prepared by quaternization and polymerization using 4-vinylpyridine and 1, 3, 5-tris(bromomethyl)-2, 4, 6-trimethylbenzene as the precursors. After loading Pd nanoparticles, they were used to catalyze decomposition of formic acid to hydrogen. Pd nanoparticles with high dispersion, small size, uniform particle size distribution and optimized electronic structure were obtained, which is benefited from the ion-exchange and N-rich characteristic of the microspheres. The effects of formic acid concentration and reaction temperature on the hydrogen production rate were investigated. The results indicated that formic acid can be completely decomposed within 30 min under the optimal reaction conditions (50 ℃, 1 mol/L of formic acid, the molar ratios of formic acid to palladium and sodium formate are 200 and 3, respectively). There is no significant decrease in the activity after the catalyst is used for 4 times.
Catalytic formic acid decomposition to hydrogen is an important route for hydrogen storage and hydrogen energy utilization. Dendritic ionic polymer microspheres were prepared by quaternization and polymerization using 4-vinylpyridine and 1, 3, 5-tris(bromomethyl)-2, 4, 6-trimethylbenzene as the precursors. After loading Pd nanoparticles, they were used to catalyze decomposition of formic acid to hydrogen. Pd nanoparticles with high dispersion, small size, uniform particle size distribution and optimized electronic structure were obtained, which is benefited from the ion-exchange and N-rich characteristic of the microspheres. The effects of formic acid concentration and reaction temperature on the hydrogen production rate were investigated. The results indicated that formic acid can be completely decomposed within 30 min under the optimal reaction conditions (50 ℃, 1 mol/L of formic acid, the molar ratios of formic acid to palladium and sodium formate are 200 and 3, respectively). There is no significant decrease in the activity after the catalyst is used for 4 times.
2020, 83(11): 1019-1024
Abstract:
In this paper, a composite photocatalytic system Pt-RGO/ZnIn2S4-CoPi/BiVO4 with reduced graphene oxide (RGO) as the electronic relay body was constructed, and its catalytic performance was evaluated by the decolorization of rhodamine B (RhB) and the photocatalytic water decomposition test. In the experiment of photocatalytic removal of RhB, the decolorization rate of RhB reached 99.89% after 3 h. In the process of photocatalytic water splitting, after 5h, the amount of H2 and O2 over the composite catalyst system reached 359.6 μmol and 196.3 μmol, respectively. Based on the above data, the working mechanism of the composite photocatalyst system is discussed. It is found that the supper photocatalytic water treatment efficiency is mainly due to RGO acting as a good electron mediator. The main reason is that RGO, as an electron relay body, promotes the conduction of photogenerated electrons between two composite monomers, thus improving the photocatalytic performance of the system.
In this paper, a composite photocatalytic system Pt-RGO/ZnIn2S4-CoPi/BiVO4 with reduced graphene oxide (RGO) as the electronic relay body was constructed, and its catalytic performance was evaluated by the decolorization of rhodamine B (RhB) and the photocatalytic water decomposition test. In the experiment of photocatalytic removal of RhB, the decolorization rate of RhB reached 99.89% after 3 h. In the process of photocatalytic water splitting, after 5h, the amount of H2 and O2 over the composite catalyst system reached 359.6 μmol and 196.3 μmol, respectively. Based on the above data, the working mechanism of the composite photocatalyst system is discussed. It is found that the supper photocatalytic water treatment efficiency is mainly due to RGO acting as a good electron mediator. The main reason is that RGO, as an electron relay body, promotes the conduction of photogenerated electrons between two composite monomers, thus improving the photocatalytic performance of the system.
2020, 83(11): 1025-1030
Abstract:
Cysteine is a reducing amino acid that plays an important role in organisms, and changes of its content in the body may induce a variety of lesions. Therefore, cysteine detection technology with high selectivity, high sensitivity and low cost is of great significance. In this paper, a guanine-rich DNA sequence is induced by potassium and sodium metal ions to form a secondary structure that has a special response to mercury ion. The cyanine dye can recognize the DNA structure, and thus cause the transformation of the supramolecular aggregation, resulting in changes in its UV and visible spectral properties. Finally, the sensor composed of Hg2+ regulating G-quadruplex and cyanine dye is utilized in the highly selective detection of cysteine in the solution system.
Cysteine is a reducing amino acid that plays an important role in organisms, and changes of its content in the body may induce a variety of lesions. Therefore, cysteine detection technology with high selectivity, high sensitivity and low cost is of great significance. In this paper, a guanine-rich DNA sequence is induced by potassium and sodium metal ions to form a secondary structure that has a special response to mercury ion. The cyanine dye can recognize the DNA structure, and thus cause the transformation of the supramolecular aggregation, resulting in changes in its UV and visible spectral properties. Finally, the sensor composed of Hg2+ regulating G-quadruplex and cyanine dye is utilized in the highly selective detection of cysteine in the solution system.
2020, 83(11): 1031-1037
Abstract:
To study the intrinsic relationship between the structure and its antioxidant activity of dandelion flavonoids from the molecular level, five important flavonoids in dandelion (quercetin, rutin, luteolin, apigenin, diosmetin) were systematically analyzed by density functional theory (DFT) calculations. The optimized geometric configuration, the relative change in energy (ΔH) associated with the formation of various flavonoid radicals, the NBO charges and spin densities analysis of the five aforementioned flavonoids were compared. The results indicated that the order of antioxidant properties is rutin > quercetin > luteolin≫diosmetin > apigenin, the location of phenol hydroxyl group significantly affects the antioxidant properties of dandelion flavonoids. The radical scavenging activity of different reactive site (-OH group) is related to the charges on H atom and the stability of flavonoid radicals, the electron delocalization and intramolecular hydrogen bond finally lead to the high activity of 4'-OH in ring B of dandelion flavonoids.
To study the intrinsic relationship between the structure and its antioxidant activity of dandelion flavonoids from the molecular level, five important flavonoids in dandelion (quercetin, rutin, luteolin, apigenin, diosmetin) were systematically analyzed by density functional theory (DFT) calculations. The optimized geometric configuration, the relative change in energy (ΔH) associated with the formation of various flavonoid radicals, the NBO charges and spin densities analysis of the five aforementioned flavonoids were compared. The results indicated that the order of antioxidant properties is rutin > quercetin > luteolin≫diosmetin > apigenin, the location of phenol hydroxyl group significantly affects the antioxidant properties of dandelion flavonoids. The radical scavenging activity of different reactive site (-OH group) is related to the charges on H atom and the stability of flavonoid radicals, the electron delocalization and intramolecular hydrogen bond finally lead to the high activity of 4'-OH in ring B of dandelion flavonoids.
2020, 83(11): 1038-1043
Abstract:
The research and development of BACE1 inhibitor has become one of the main research directions in the treatment of Alzheimer's disease (AD). In this study, 105 aminohydantoins BACE1 inhibitors were selected as research objects. By virtue of Comparative Molecular Similarity Index (CoMSIA) and molecular docking method, a prediction model of quantitative structure-activity relationship was established to study the structural feature information that influences the inhibitory activity of compounds and reveal the mode of action between these inhibitors and targets. The results showed that the model possesses a strong prediction ability (Q2=0.45, Rncv2=0.87, Rpre2=0.85), and the inhibitors mainly occupy the S3, S1 and S2' active sites of target through the hydrogen bond force. The model and information obtained from the experiment can provide theoretical guidance for the development of new and effective BACE1 inhibitors.
The research and development of BACE1 inhibitor has become one of the main research directions in the treatment of Alzheimer's disease (AD). In this study, 105 aminohydantoins BACE1 inhibitors were selected as research objects. By virtue of Comparative Molecular Similarity Index (CoMSIA) and molecular docking method, a prediction model of quantitative structure-activity relationship was established to study the structural feature information that influences the inhibitory activity of compounds and reveal the mode of action between these inhibitors and targets. The results showed that the model possesses a strong prediction ability (Q2=0.45, Rncv2=0.87, Rpre2=0.85), and the inhibitors mainly occupy the S3, S1 and S2' active sites of target through the hydrogen bond force. The model and information obtained from the experiment can provide theoretical guidance for the development of new and effective BACE1 inhibitors.
2020, 83(11): 1044-1049
Abstract:
T-type and KA zeolite membranes were synthesized on the alumina ceramics substrate and applied to model natural gas (mathane gas with 3.5% water vapor) dehydration. The model natural gas dehydration performance showed that the H2O/CH4 selectivities for model natural gas removal were 2.80 and 3.16 respectively for the T-type and KA zeolite membranes. Furthermore, the surface coating method was used to repair the defects in the zeolite membrane, thereby effectively improving its performance on the dehydration of model natural gas the H2O/CH4 selectivities up to 10.52 and 17.71, with the water vapor permeability coefficients of 104397 Barrer and 28200 Barrer and the methane loss rates of only 2% and 1%, respectively. The two repaired zeolite membranes had good stability.
T-type and KA zeolite membranes were synthesized on the alumina ceramics substrate and applied to model natural gas (mathane gas with 3.5% water vapor) dehydration. The model natural gas dehydration performance showed that the H2O/CH4 selectivities for model natural gas removal were 2.80 and 3.16 respectively for the T-type and KA zeolite membranes. Furthermore, the surface coating method was used to repair the defects in the zeolite membrane, thereby effectively improving its performance on the dehydration of model natural gas the H2O/CH4 selectivities up to 10.52 and 17.71, with the water vapor permeability coefficients of 104397 Barrer and 28200 Barrer and the methane loss rates of only 2% and 1%, respectively. The two repaired zeolite membranes had good stability.
2020, 83(11): 1050-1055
Abstract:
In 1791, British mineralogist Gregor discovered titanium ore and realized the existence of a new element. By 1795, the Prussian chemist Klaproth had further predicted the existence of the element and officially named it Titanium. In 1910, the American chemist Hunter made pure titanium, and the concept of titanium element was formally formed. After the 1920s, the discovery of titanium isotopes gave people a new understanding of the concept of titanium, and gradually formed a modern concept of titanium. The development of the concept of titanium element has changed people's scientific understanding and promoted the evolution of the concept of chemical elements.
In 1791, British mineralogist Gregor discovered titanium ore and realized the existence of a new element. By 1795, the Prussian chemist Klaproth had further predicted the existence of the element and officially named it Titanium. In 1910, the American chemist Hunter made pure titanium, and the concept of titanium element was formally formed. After the 1920s, the discovery of titanium isotopes gave people a new understanding of the concept of titanium, and gradually formed a modern concept of titanium. The development of the concept of titanium element has changed people's scientific understanding and promoted the evolution of the concept of chemical elements.
