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2020 Volume 37 Issue 9
2020, 37(9): 977-984
doi: 10.11944/j.issn.1000-0518.2020.09.200164
Abstract:
Tumor immunotherapy is a new technique for cancer treatment. However, the low clinical response rate of tumor immunotherapy at this stage seriously restricts its further application. The fundamental reason is that the immunosuppressive microenvironment of tumor tissue limits the antitumor activity of T cells, and the metabolic changes of tumor tissue play a key role in the formation of tumor immunosuppressive microenvironment. In this paper, we focus on enhancing the antitumor activity of T cells by regulating the aerobic glycolysis, amino acid metabolism and fatty acid metabolism of tumors. Finally, the current problems in the research of tumor metabolism regulation are proposed, and the development prospects of nanocarriers in the field of tumor metabolism are prospected.
Tumor immunotherapy is a new technique for cancer treatment. However, the low clinical response rate of tumor immunotherapy at this stage seriously restricts its further application. The fundamental reason is that the immunosuppressive microenvironment of tumor tissue limits the antitumor activity of T cells, and the metabolic changes of tumor tissue play a key role in the formation of tumor immunosuppressive microenvironment. In this paper, we focus on enhancing the antitumor activity of T cells by regulating the aerobic glycolysis, amino acid metabolism and fatty acid metabolism of tumors. Finally, the current problems in the research of tumor metabolism regulation are proposed, and the development prospects of nanocarriers in the field of tumor metabolism are prospected.
2020, 37(9): 985-993
doi: 10.11944/j.issn.1000-0518.2020.09.200225
Abstract:
Biosafety has become one of the major threats to the survival of people and development of the whole world. After the outbreak of novel coronavirus pneumonia (COVID-19), the strategic role of biosafety becomes more important, especially under the situation of national normalization of anti-epidemic. Upgrading biosafety not only enriches the elements of the national security system, but also promotes the national security. Many problems were exposed in the outbreak of COVID-19. In the early stage of the outbreak in China, there was a serious lack of first-line personal protective equipment (PPE) and detection kits, which was partially due to the lack of development of biosafety related materials in China. It is of great significance to develop new materials to deal with biosafety risk factors, strengthen the construction of biosafety materials discipline and personnel training, and promote the development of biosafety materials. Ultimately, the development of biosafety materials science will provide a solid guarantee for the health and well-being of society, economic prosperity, and national security.
Biosafety has become one of the major threats to the survival of people and development of the whole world. After the outbreak of novel coronavirus pneumonia (COVID-19), the strategic role of biosafety becomes more important, especially under the situation of national normalization of anti-epidemic. Upgrading biosafety not only enriches the elements of the national security system, but also promotes the national security. Many problems were exposed in the outbreak of COVID-19. In the early stage of the outbreak in China, there was a serious lack of first-line personal protective equipment (PPE) and detection kits, which was partially due to the lack of development of biosafety related materials in China. It is of great significance to develop new materials to deal with biosafety risk factors, strengthen the construction of biosafety materials discipline and personnel training, and promote the development of biosafety materials. Ultimately, the development of biosafety materials science will provide a solid guarantee for the health and well-being of society, economic prosperity, and national security.
2020, 37(9): 994-1002
doi: 10.11944/j.issn.1000-0518.2020.09.200040
Abstract:
A series of 3, 6-disubstituted triazolothiadiazole derivatives 3a-3l containing benzimidazole/aryloxymethyl scaffolds was synthesized. Their structures were confirmed by Fourier transform infrared spectrometry (FT-IR), nuclear magnetic resonance spectroscopy (NMR) and elemental analysis. The inhibitory activity of all synthesized target compounds against cell division cycle 25B phosphatase (Cdc25B)/protein tyrosine phosphatase 1B (PTP1B) was evaluated, and the structure-activity relationship was discussed. The bioassay results show that target compound 3a has the highest inhibitory activity against Cdc25B and PTP1B with the half inhibitory concentration (IC50) values of (0.46±0.02) μg/mL and (1.77±0.40) μg/mL, respectively. The obtained research results provide a reference for the development of novel Cdc25B/PTP1B inhibitors.
A series of 3, 6-disubstituted triazolothiadiazole derivatives 3a-3l containing benzimidazole/aryloxymethyl scaffolds was synthesized. Their structures were confirmed by Fourier transform infrared spectrometry (FT-IR), nuclear magnetic resonance spectroscopy (NMR) and elemental analysis. The inhibitory activity of all synthesized target compounds against cell division cycle 25B phosphatase (Cdc25B)/protein tyrosine phosphatase 1B (PTP1B) was evaluated, and the structure-activity relationship was discussed. The bioassay results show that target compound 3a has the highest inhibitory activity against Cdc25B and PTP1B with the half inhibitory concentration (IC50) values of (0.46±0.02) μg/mL and (1.77±0.40) μg/mL, respectively. The obtained research results provide a reference for the development of novel Cdc25B/PTP1B inhibitors.
2020, 37(9): 1003-1009
doi: 10.11944/j.issn.1000-0518.2020.09.200100
Abstract:
Fluorescent nanobioprobes with cell-targeting specificity are promising to find important applications in bioanalysis, biomedicine, and clinical diagnosis. In this work, folic acid-carbon dot conjugates (FA-CDs) were prepared via hydrothermal method and 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride (EDC) chemistry. The as-prepared FA-CDs with low toxicity and high luminescence can specifically target cancer cells. The specificity of this receptor-mediated internalization was confirmed by comparing the uptake by Hela and NIH-3T3 cells. This work is of great significance for the early diagnosis of cancer cells.
Fluorescent nanobioprobes with cell-targeting specificity are promising to find important applications in bioanalysis, biomedicine, and clinical diagnosis. In this work, folic acid-carbon dot conjugates (FA-CDs) were prepared via hydrothermal method and 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride (EDC) chemistry. The as-prepared FA-CDs with low toxicity and high luminescence can specifically target cancer cells. The specificity of this receptor-mediated internalization was confirmed by comparing the uptake by Hela and NIH-3T3 cells. This work is of great significance for the early diagnosis of cancer cells.
2020, 37(9): 1010-1021
doi: 10.11944/j.issn.1000-0518.2020.09.200042
Abstract:
Cardiovascular diseases currently dominate the cause of death worldwide. Oxidative stress injury is one of the important pathogenesis of cardiovascular diseases. The purpose of this study is to investigate the antioxidative protection effect of molybdenum disulfide (MoS2) nanoparticles on cardiomyocytes under oxidative stress injury. We synthesized MoS2 nanoparticles with antioxidant-like enzyme activity by a one-step hydrothermal method. MTT, intracellular apoptosis, intracellular reactive oxygen species (ROS) detection, and Western Blot experiments confirm that MoS2 nanoparticles (100 μg/mL) can protect H9c2 cardiomyocytes from oxidative stress injury induced by hydrogen peroxide (H2O2). At the same time, it also promotes the proliferation of H9c2 cardiomyocytes. This study shows that MoS2 nanoparticles can be used to construct antioxidant defense against cardiovascular diseases caused by oxidative stress injury, and provide experimental data and theoretical basis for the development of nanomedicine in the resistance to myocardial oxidative damage.
Cardiovascular diseases currently dominate the cause of death worldwide. Oxidative stress injury is one of the important pathogenesis of cardiovascular diseases. The purpose of this study is to investigate the antioxidative protection effect of molybdenum disulfide (MoS2) nanoparticles on cardiomyocytes under oxidative stress injury. We synthesized MoS2 nanoparticles with antioxidant-like enzyme activity by a one-step hydrothermal method. MTT, intracellular apoptosis, intracellular reactive oxygen species (ROS) detection, and Western Blot experiments confirm that MoS2 nanoparticles (100 μg/mL) can protect H9c2 cardiomyocytes from oxidative stress injury induced by hydrogen peroxide (H2O2). At the same time, it also promotes the proliferation of H9c2 cardiomyocytes. This study shows that MoS2 nanoparticles can be used to construct antioxidant defense against cardiovascular diseases caused by oxidative stress injury, and provide experimental data and theoretical basis for the development of nanomedicine in the resistance to myocardial oxidative damage.
2020, 37(9): 1022-1029
doi: 10.11944/j.issn.1000-0518.2020.09.200015
Abstract:
In order to study the optical properties of intramolecular charge transfer compounds of small organic molecular systems with donor-acceptor structure, two kinds of π-conjugated intramolecular charge transfer(ICT)derivatives ((E)-4-((4-(4-(9H-carbazol-9-yl)styryl)phenyl)ethynyl)-7-bromobenzo[c][1, 2, 5]thiadiazole (CzPB-Br) and 4, 7-bis((4-((E)-4-(9H-carbazol-9-yl)styryl)phenyl)ethynyl)benzo[c][1, 2, 5]thiadiazole (CzPBPCz)) were synthesized, where the donor part consists of carbazole unit, while benzothiadiazole works as the acceptor. The influence of different conjugated groups on the structure and photophysical properties were studided by ultraviolet-visible (UV-Vis) spectra, fluorescence spectra and theoretical calculations. CzPB-Br and CzPBPCz have characteristic UV-Vis absorption peaks at 404 and 442 nm in CH2Cl2, respectively, with the maximum fluorescence wavelengths at 557 and 588 nm, respectively. The well-defined one-dimensional microrods and polygonal micron plates in large quantities and with high morphological purity are successfully fabricated adopting a phase transfer methodology and precipitation of hot saturated solution, exhibiting green and yellow emission respectively (emission maximum centered at 515 and 568 nm). The length of one-dimensional microrod is more than 100 μm with the width of 1~2 μm. Meanwhile, these assembles show a typical characteristics of waveguiding behavior, endowing potential applications in the field of optical devices.
In order to study the optical properties of intramolecular charge transfer compounds of small organic molecular systems with donor-acceptor structure, two kinds of π-conjugated intramolecular charge transfer(ICT)derivatives ((E)-4-((4-(4-(9H-carbazol-9-yl)styryl)phenyl)ethynyl)-7-bromobenzo[c][1, 2, 5]thiadiazole (CzPB-Br) and 4, 7-bis((4-((E)-4-(9H-carbazol-9-yl)styryl)phenyl)ethynyl)benzo[c][1, 2, 5]thiadiazole (CzPBPCz)) were synthesized, where the donor part consists of carbazole unit, while benzothiadiazole works as the acceptor. The influence of different conjugated groups on the structure and photophysical properties were studided by ultraviolet-visible (UV-Vis) spectra, fluorescence spectra and theoretical calculations. CzPB-Br and CzPBPCz have characteristic UV-Vis absorption peaks at 404 and 442 nm in CH2Cl2, respectively, with the maximum fluorescence wavelengths at 557 and 588 nm, respectively. The well-defined one-dimensional microrods and polygonal micron plates in large quantities and with high morphological purity are successfully fabricated adopting a phase transfer methodology and precipitation of hot saturated solution, exhibiting green and yellow emission respectively (emission maximum centered at 515 and 568 nm). The length of one-dimensional microrod is more than 100 μm with the width of 1~2 μm. Meanwhile, these assembles show a typical characteristics of waveguiding behavior, endowing potential applications in the field of optical devices.
2020, 37(9): 1030-1037
doi: 10.11944/j.issn.1000-0518.2020.09.200047
Abstract:
In this paper, a series of Ag3PO4 quantum dots/g-C3N4 nanosheet composite photocatalysts was prepared at room temperature for the first time with the ultrathin g-C3N4 nanosheet exfoliated by thermal oxidation as the support. The morphology, structure and optical properties of the photocatalysts were characterized by transmission electron microscopy(TEM), high resolution TEM(HRTEM), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy analysis (FT-IR), ultraviolet-visible diffuse-reflectance spectroscopy (UV-Vis DRS), photoluminescence spectroscopy (PL) techniques. The photocatalytic selective oxidation of benzyl alcohol was investigated. The results show that quantum dots of well-crystallized Ag3PO4 with the particle size of 3~5 nm are homogeneously dispersed on the g-C3N4 nanosheet. For the photocatalysts with the mass ratio of 0.6 Ag3PO4 to g-C3N4 in acetonitrile, the maximum conversion of benzyl alcohol is 32.1%, and the highest selectivity of benzaldehyde is 90%. The results of active species capture experiment show that the main active species of photogenerated hole are responsible for the selective oxidation. The results of energy band calculation show that the composite catalyst has a suitable oxidation potential for benzyl alcohol into benzaldehyde.
In this paper, a series of Ag3PO4 quantum dots/g-C3N4 nanosheet composite photocatalysts was prepared at room temperature for the first time with the ultrathin g-C3N4 nanosheet exfoliated by thermal oxidation as the support. The morphology, structure and optical properties of the photocatalysts were characterized by transmission electron microscopy(TEM), high resolution TEM(HRTEM), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy analysis (FT-IR), ultraviolet-visible diffuse-reflectance spectroscopy (UV-Vis DRS), photoluminescence spectroscopy (PL) techniques. The photocatalytic selective oxidation of benzyl alcohol was investigated. The results show that quantum dots of well-crystallized Ag3PO4 with the particle size of 3~5 nm are homogeneously dispersed on the g-C3N4 nanosheet. For the photocatalysts with the mass ratio of 0.6 Ag3PO4 to g-C3N4 in acetonitrile, the maximum conversion of benzyl alcohol is 32.1%, and the highest selectivity of benzaldehyde is 90%. The results of active species capture experiment show that the main active species of photogenerated hole are responsible for the selective oxidation. The results of energy band calculation show that the composite catalyst has a suitable oxidation potential for benzyl alcohol into benzaldehyde.
2020, 37(9): 1038-1047
doi: 10.11944/j.issn.1000-0518.2020.09.200055
Abstract:
Two supported acidic ionic liquids (ILs) consisting of SBA-15-ILs (SILs) and Zr-Ce-SBA-15-ILs(ZCSILs) were prepared by combining acidic ionic liquids with the silica-based support. The physio-chemical properties of the obtained catalysts were characterized by Fourier transform infrared (FT-IR) spectroscopy, thermalgravimetry-differential thermal gravimetry (TG-DTG), X-ray diffraction (XRD), Brunauer Emmett Teller (BET), transimition electron microscopy (TEM), scanning electron microscopy (SEM) and organic elemental analysis (OEA) measurements. The catalytic activity of the prepared catalysts was evaluated in the hydroxyalkylation of phenol and aqueous formaldehyde to bisphenol F. The effects of operating variables, such as type of catalysts, molar ratio of phenol to formaldehyde, reaction temperature, reaction time and addition of catalysts on the yield of BPF and selectivity were investigated. Under the optimum conditions (catalyst/formaldehyde mass ratio 0.36, phenol/formaldehyde molar ratio 30:1, reaction temperature 80 ℃ and reaction time 60 min), a high bisphenol F yield of 95.6% with 44.8% selectivity to 4, 4'-BPF can be achieved over the short-channeled ZCSILs catalyst with large specific surface area and high loading amount of ionic liquids and its catalytic activity is still good after being reused for 5 times.
Two supported acidic ionic liquids (ILs) consisting of SBA-15-ILs (SILs) and Zr-Ce-SBA-15-ILs(ZCSILs) were prepared by combining acidic ionic liquids with the silica-based support. The physio-chemical properties of the obtained catalysts were characterized by Fourier transform infrared (FT-IR) spectroscopy, thermalgravimetry-differential thermal gravimetry (TG-DTG), X-ray diffraction (XRD), Brunauer Emmett Teller (BET), transimition electron microscopy (TEM), scanning electron microscopy (SEM) and organic elemental analysis (OEA) measurements. The catalytic activity of the prepared catalysts was evaluated in the hydroxyalkylation of phenol and aqueous formaldehyde to bisphenol F. The effects of operating variables, such as type of catalysts, molar ratio of phenol to formaldehyde, reaction temperature, reaction time and addition of catalysts on the yield of BPF and selectivity were investigated. Under the optimum conditions (catalyst/formaldehyde mass ratio 0.36, phenol/formaldehyde molar ratio 30:1, reaction temperature 80 ℃ and reaction time 60 min), a high bisphenol F yield of 95.6% with 44.8% selectivity to 4, 4'-BPF can be achieved over the short-channeled ZCSILs catalyst with large specific surface area and high loading amount of ionic liquids and its catalytic activity is still good after being reused for 5 times.
2020, 37(9): 1056-1061
doi: 10.11944/j.issn.1000-0518.2020.09.200066
Abstract:
In this paper, a kind of bulk submicron red phosphorus/graphite composite (smRP/G) was studied, which was prepared by mechanical ball milling submicron red phosphorus and graphite. Its characteristics were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammogram (CV) and etc. Compared with common red new energystorage materials, new catalytic materials, submicron red phosphorus is easier to form composites with graphite by ball milling, which can effectively improve the lithium storage capacity of graphite materials. It provides an idea for the application of red phosphorus in the negative electrode materials of lithium-ion batteries. In this work, under the condition of adding a mass percent of 3% red phosphorus, smRP/G shows the best performance. At the current density of 100 mA/g, the first discharge capacity of 1417 mA·h/g is displayed, and the first coulomb efficiency is 67.4%. The reversible capacity of 700 mA·h/g is maintained after 200 cycles.
In this paper, a kind of bulk submicron red phosphorus/graphite composite (smRP/G) was studied, which was prepared by mechanical ball milling submicron red phosphorus and graphite. Its characteristics were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammogram (CV) and etc. Compared with common red new energystorage materials, new catalytic materials, submicron red phosphorus is easier to form composites with graphite by ball milling, which can effectively improve the lithium storage capacity of graphite materials. It provides an idea for the application of red phosphorus in the negative electrode materials of lithium-ion batteries. In this work, under the condition of adding a mass percent of 3% red phosphorus, smRP/G shows the best performance. At the current density of 100 mA/g, the first discharge capacity of 1417 mA·h/g is displayed, and the first coulomb efficiency is 67.4%. The reversible capacity of 700 mA·h/g is maintained after 200 cycles.
2020, 37(9): 1062-1068
doi: 10.11944/j.issn.1000-0518.2020.09.200076
Abstract:
In this study, we explored a one-step hydrothermal synthesis method to synthesize catechin-silver nanocomposite wherein catechin was acted as the reduction agent and protection agent. The ultrviolet-visible (UV-Vis) and Fourier transform infrared spectroscopy(FTIR) measurements confirm that the obtained nanomaterials are catechin-capped Ag nanoparticles. Transmission electron microscopy(TEM) and X-ray diffraction(XRD) results indicate that the average diameter of the Ag nanoparticles is 22.7 nm, and the Ag nanoparticles have the face centered cubic crystal structure. We further studied the antibacterial activity of catechin-silver nanoparticles. The results of bacteriostatic experiments reveal that the catechin-silver nanoparticles have a strong inhibitory effect on E.coli, S.aureus and C.albicans. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) for C.albicans is 19.63 and 39.26 μg/mL, respectively. The inhibitory activity of catechin-silver nanoparticles can be attributed to the continuous release of Ag+ from their surface. The catechin-silver nanocomposite is expected to be used in long-acting antibacterial agents.
In this study, we explored a one-step hydrothermal synthesis method to synthesize catechin-silver nanocomposite wherein catechin was acted as the reduction agent and protection agent. The ultrviolet-visible (UV-Vis) and Fourier transform infrared spectroscopy(FTIR) measurements confirm that the obtained nanomaterials are catechin-capped Ag nanoparticles. Transmission electron microscopy(TEM) and X-ray diffraction(XRD) results indicate that the average diameter of the Ag nanoparticles is 22.7 nm, and the Ag nanoparticles have the face centered cubic crystal structure. We further studied the antibacterial activity of catechin-silver nanoparticles. The results of bacteriostatic experiments reveal that the catechin-silver nanoparticles have a strong inhibitory effect on E.coli, S.aureus and C.albicans. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) for C.albicans is 19.63 and 39.26 μg/mL, respectively. The inhibitory activity of catechin-silver nanoparticles can be attributed to the continuous release of Ag+ from their surface. The catechin-silver nanocomposite is expected to be used in long-acting antibacterial agents.
2020, 37(9): 1069-1075
doi: 10.11944/j.issn.1000-0518.2020.09.200045
Abstract:
As an effective way to detect quercetin, it is important to synthesize fluorescent probe with excellent performance by a simple method. In this work, a facile one-pot approach has been developed to prepare blue-emitting Cu nanoclusters (NCs) using ascorbic acid as a reducing agent and polyvinyl pyrrolidone (PVP) as a capping agent. The PVP-stabilized PVP-Cu NCs display good dispersion, high stability and strong fluorescence. It exhibits good water solubility, excellent photostability and high stability toward high concentration of sodium chloride. The optical performance and structure of PVP-Cu NCs were characterized by ultraviolet-visible (UV-Vis) absorption spectroscopy, fluorescence spectroscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The characterization results show that PVP-Cu NCs have a strong symmetric emission at 429 nm with a maximum excitation at 366 nm. TEM analysis shows that the average diameter of PVP-Cu NCs is 2.0 nm. We construct a fluorescent sensor for the detection of quercetin on the basis of the quenching effect of quercetin on the fluorescence of PVP-Cu NCs. The experimental results show that the quercetin sensing system has a linear range of 0.1~0.9 μmol/L and 15~60 μmol/L with a low detection limit (S/N=3) of 0.053 μmol/L. The sensor has high sensitivity and good selectivity for the detection of quercetin, and can be applied for quercetin detection in real samples.
As an effective way to detect quercetin, it is important to synthesize fluorescent probe with excellent performance by a simple method. In this work, a facile one-pot approach has been developed to prepare blue-emitting Cu nanoclusters (NCs) using ascorbic acid as a reducing agent and polyvinyl pyrrolidone (PVP) as a capping agent. The PVP-stabilized PVP-Cu NCs display good dispersion, high stability and strong fluorescence. It exhibits good water solubility, excellent photostability and high stability toward high concentration of sodium chloride. The optical performance and structure of PVP-Cu NCs were characterized by ultraviolet-visible (UV-Vis) absorption spectroscopy, fluorescence spectroscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The characterization results show that PVP-Cu NCs have a strong symmetric emission at 429 nm with a maximum excitation at 366 nm. TEM analysis shows that the average diameter of PVP-Cu NCs is 2.0 nm. We construct a fluorescent sensor for the detection of quercetin on the basis of the quenching effect of quercetin on the fluorescence of PVP-Cu NCs. The experimental results show that the quercetin sensing system has a linear range of 0.1~0.9 μmol/L and 15~60 μmol/L with a low detection limit (S/N=3) of 0.053 μmol/L. The sensor has high sensitivity and good selectivity for the detection of quercetin, and can be applied for quercetin detection in real samples.
2020, 37(9): 1076-1086
doi: 10.11944/j.issn.1000-0518.2020.09.200028
Abstract:
A type of magnetic ion-imprinted polymer based on magnetic graphene oxide/MIL-101(Cr) was synthesized with surface imprinting technology using magnetic graphene oxide/MIL-101(Cr) composite as the supporting material, Cu(Ⅱ), Pb(Ⅱ) as the templates, and dopamine as the functional monomer. Fourier-transform infrared spectroscopy, scanning electron microscopy, and vibrating sample magnetometry were used to characterize the morphology, particle size, and magnetic properties of the magnetic ion-imprinted polymer. The adsorption kinetics, isothermal adsorption performance and adsorption selectivity of the magnetic ion-imprinted polymer toward Cu(Ⅱ) and Pb(Ⅱ) were investigated in details. The results show that the magnetic ion-imprinted polymer has a superior adsorption performance toward Cu(Ⅱ) and Pb(Ⅱ) with the maximum adsorption capacity of 144.92 and 322.58 mg/g, respectively. The magnetic solid-phase extraction conditions were optimized in details. The magnetic ion-imprinted polymer was successfully used for the separation and detection of trace amounts of Cu(Ⅱ) and Pb(Ⅱ) in water samples. The recoveries of Cu(Ⅱ) and Pb(Ⅱ) are 81.99%~89.91% and 81.24%~95.15%, respectively.
A type of magnetic ion-imprinted polymer based on magnetic graphene oxide/MIL-101(Cr) was synthesized with surface imprinting technology using magnetic graphene oxide/MIL-101(Cr) composite as the supporting material, Cu(Ⅱ), Pb(Ⅱ) as the templates, and dopamine as the functional monomer. Fourier-transform infrared spectroscopy, scanning electron microscopy, and vibrating sample magnetometry were used to characterize the morphology, particle size, and magnetic properties of the magnetic ion-imprinted polymer. The adsorption kinetics, isothermal adsorption performance and adsorption selectivity of the magnetic ion-imprinted polymer toward Cu(Ⅱ) and Pb(Ⅱ) were investigated in details. The results show that the magnetic ion-imprinted polymer has a superior adsorption performance toward Cu(Ⅱ) and Pb(Ⅱ) with the maximum adsorption capacity of 144.92 and 322.58 mg/g, respectively. The magnetic solid-phase extraction conditions were optimized in details. The magnetic ion-imprinted polymer was successfully used for the separation and detection of trace amounts of Cu(Ⅱ) and Pb(Ⅱ) in water samples. The recoveries of Cu(Ⅱ) and Pb(Ⅱ) are 81.99%~89.91% and 81.24%~95.15%, respectively.
2020, 37(9): 1087-1092
doi: 10.11944/j.issn.1000-0518.2020.09.200026
Abstract:
Ce(III) test paper was prepared for the detection of Ce3+ concentration using medium-speed quantitative filter paper as the base paper, 0.5% mass fraction cetyltrimethylammonium bromide as a modifier for base paper and 0.2% mass fraction xylenol orange as the color reagent adsorbed on base paper sequentially. A standard color chart including 11 colors was made by soaking the test paper in a series of Ce3+ standard solution in the concentration range of 1.000×10-5 to 1.000 mol/L. A semi-quantitative method was established for detection of Ce3+ concentration in the mixed solution of Ce4+/Ce3+. The method was used for detection of Ce3+ in an electrolyte or organic reaction fluid containing Ce4+, hydroquinone, p-hydroxybenzaldehyde and 1, 10-dihydroxyanthraquinone in the buffer solution of hexamethylenetetramine at pH 5.0~6.0. The results show that the method has a good accuracy and those coexisting components do not interfere with the determination. The test paper has advantages of simple manufacturing, cheapness, fast detection speed and easy operation. It is applied to the rapid monitoring of Ce3+ concentration in the production process.
Ce(III) test paper was prepared for the detection of Ce3+ concentration using medium-speed quantitative filter paper as the base paper, 0.5% mass fraction cetyltrimethylammonium bromide as a modifier for base paper and 0.2% mass fraction xylenol orange as the color reagent adsorbed on base paper sequentially. A standard color chart including 11 colors was made by soaking the test paper in a series of Ce3+ standard solution in the concentration range of 1.000×10-5 to 1.000 mol/L. A semi-quantitative method was established for detection of Ce3+ concentration in the mixed solution of Ce4+/Ce3+. The method was used for detection of Ce3+ in an electrolyte or organic reaction fluid containing Ce4+, hydroquinone, p-hydroxybenzaldehyde and 1, 10-dihydroxyanthraquinone in the buffer solution of hexamethylenetetramine at pH 5.0~6.0. The results show that the method has a good accuracy and those coexisting components do not interfere with the determination. The test paper has advantages of simple manufacturing, cheapness, fast detection speed and easy operation. It is applied to the rapid monitoring of Ce3+ concentration in the production process.
2020, 37(9): 1093-1098
doi: 10.11944/j.issn.1000-0518.2020.09.200077
Abstract:
The metal anode of the metal-air battery is in contact with the electrolyte during the shutdown and the corrosion occurs, which seriously affects the shelf life of the metal-air battery. Through the simple improvement of the structure of the conventional metal-air battery, the shutdown corrosion problem of metal-air batteries is solved by using the Kipp's apparatus principle so that the metal-air battery can last longer. The single cells of metal-air battery before and after the structural improvement were constructed with aluminum foil as the metal anode and the intermittent constant current discharge was carried out to test the shutdown life of the battery. The shutdown corrosion situation of the anode was quantitatively studied by the mass loss experiment and the hydrogen evolution loss experiment. The results show that when 0.25 mm thick aluminum foil is used as the metal anode, the shutdown life of metal-air battery before and after structural improvement is 4 and 21 days, respectively. The anode corrosion rate of the improved metal-air battery is much slower than that of the conventional metal-air battery. For a single battery, only about 0.0380 g of aluminum is needed to generate the hydrogen required for solid-liquid separation, which is about 0.038% of the general commercial aluminum anode.
The metal anode of the metal-air battery is in contact with the electrolyte during the shutdown and the corrosion occurs, which seriously affects the shelf life of the metal-air battery. Through the simple improvement of the structure of the conventional metal-air battery, the shutdown corrosion problem of metal-air batteries is solved by using the Kipp's apparatus principle so that the metal-air battery can last longer. The single cells of metal-air battery before and after the structural improvement were constructed with aluminum foil as the metal anode and the intermittent constant current discharge was carried out to test the shutdown life of the battery. The shutdown corrosion situation of the anode was quantitatively studied by the mass loss experiment and the hydrogen evolution loss experiment. The results show that when 0.25 mm thick aluminum foil is used as the metal anode, the shutdown life of metal-air battery before and after structural improvement is 4 and 21 days, respectively. The anode corrosion rate of the improved metal-air battery is much slower than that of the conventional metal-air battery. For a single battery, only about 0.0380 g of aluminum is needed to generate the hydrogen required for solid-liquid separation, which is about 0.038% of the general commercial aluminum anode.
2020, 37(9): 1048-1055
doi: 10.11944/j.issn.1000-0518.2020.09.200085
Abstract:
NH3 plays an important role in human production and life, but the main way to produce NH3 is still the high energy consumption and high pollution Haber-Bosch process. Electrocatalytic N2 reduction reaction (ENRR) is considered to be an effective alternative method, however highly efficient catalyst is still a challenging as a result of high bond energy of N≡N. Here, we report an electrocatalyst of polyvalent MnOx/C which is designed via simple redox reaction for highly efficient production of ammonia (with yield up to 7.8 μgNH3/(h·mgcat) and Faradic efficiency (FE) up to 9.2%) from nitrogen reduction reaction (NRR). The high NRR performance of polyvalent MnOx/C mainly originates from a synergistic effect among different valence states (Mn2+, Mn3+, Mn4+) of Mn for NRR.
NH3 plays an important role in human production and life, but the main way to produce NH3 is still the high energy consumption and high pollution Haber-Bosch process. Electrocatalytic N2 reduction reaction (ENRR) is considered to be an effective alternative method, however highly efficient catalyst is still a challenging as a result of high bond energy of N≡N. Here, we report an electrocatalyst of polyvalent MnOx/C which is designed via simple redox reaction for highly efficient production of ammonia (with yield up to 7.8 μgNH3/(h·mgcat) and Faradic efficiency (FE) up to 9.2%) from nitrogen reduction reaction (NRR). The high NRR performance of polyvalent MnOx/C mainly originates from a synergistic effect among different valence states (Mn2+, Mn3+, Mn4+) of Mn for NRR.
