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2020 Volume 83 Issue 5
2020, 83(5): 387-393
Abstract:
Actinide supermolecular chemistry is one of the recently emerging research areas of actinide chemistry, which can provide important information for the basic research of coordination chemistry of spent fuel reprocessing, and also explore the function and potential application of actinide functional materials in the fields of luminescence, catalysis, separation et al. This review will introduce recent progresses in actinide-based supramolecular assemblies. Starting from the construction principle of actinide-based supramolecular assemblies, and in combination with the author's own research works, the progresses of three typical kinds of actinide supramolecular assemblies including actinide-rotaxane complexes based on host-guest rotaxane ligands, actinide coordination complexes with closed structures and actinide supramolecular polymers based on supramolecular interactions are reviewed and summarized. We hope the paper can provide a reference for the design and synthesis of new actinide-based supramolecular assemblies in the future and promote the development of related fields of actinide chemistry and mateirals.
Actinide supermolecular chemistry is one of the recently emerging research areas of actinide chemistry, which can provide important information for the basic research of coordination chemistry of spent fuel reprocessing, and also explore the function and potential application of actinide functional materials in the fields of luminescence, catalysis, separation et al. This review will introduce recent progresses in actinide-based supramolecular assemblies. Starting from the construction principle of actinide-based supramolecular assemblies, and in combination with the author's own research works, the progresses of three typical kinds of actinide supramolecular assemblies including actinide-rotaxane complexes based on host-guest rotaxane ligands, actinide coordination complexes with closed structures and actinide supramolecular polymers based on supramolecular interactions are reviewed and summarized. We hope the paper can provide a reference for the design and synthesis of new actinide-based supramolecular assemblies in the future and promote the development of related fields of actinide chemistry and mateirals.
2020, 83(5): 394-403
Abstract:
Two-dimensional (2D) polymers have great potential in the fields of optoelectronics, catalysis, energy storage, gas storage and separation, etc. Among them, sp2-Carbon (Csp2) linked 2D polymers have shown unique electrical and chemical features. Atomic precisely polymerization through scanning tunneling microscopy (STM) technology on lattice surfaces, including Au(111), Ag(111), Cu(111), Ru(111), HOPG, have provided an effective new strategy for constructing Csp2-linked 2D polymers. STM technology has high resolution capabilities and can be adopted for structural characterization and intrinsic optoelectronic and magnetic properties understanding. This review will introduce the study of 2D polymers based on Csp2 connection under STM technology.
Two-dimensional (2D) polymers have great potential in the fields of optoelectronics, catalysis, energy storage, gas storage and separation, etc. Among them, sp2-Carbon (Csp2) linked 2D polymers have shown unique electrical and chemical features. Atomic precisely polymerization through scanning tunneling microscopy (STM) technology on lattice surfaces, including Au(111), Ag(111), Cu(111), Ru(111), HOPG, have provided an effective new strategy for constructing Csp2-linked 2D polymers. STM technology has high resolution capabilities and can be adopted for structural characterization and intrinsic optoelectronic and magnetic properties understanding. This review will introduce the study of 2D polymers based on Csp2 connection under STM technology.
2020, 83(5): 404-417
Abstract:
There is an urgent need to develop catalysts in line with environmental concerns. The abundant and non-toxic dual character of the iron element is fully consistent with this trend. In the past decades, catalysis based on well-defined iron complexes has experienced a very rapid growth. After the pioneering work of Gibson and Brookhart related to the polymerization of ethylene, it appeared in the literature an increasing number of studies on the coordination-insertion polymerization of 1, 3-dienes using iron-based catalytic systems. The purpose of this review is to provide an update in this field by examining the catalytic systems developed in recent years. Particular emphasis is placed on those involving discrete complexes through their structure and catalytic performance, in terms of both activity and selectivity (when relevant) as well as their limitations.
There is an urgent need to develop catalysts in line with environmental concerns. The abundant and non-toxic dual character of the iron element is fully consistent with this trend. In the past decades, catalysis based on well-defined iron complexes has experienced a very rapid growth. After the pioneering work of Gibson and Brookhart related to the polymerization of ethylene, it appeared in the literature an increasing number of studies on the coordination-insertion polymerization of 1, 3-dienes using iron-based catalytic systems. The purpose of this review is to provide an update in this field by examining the catalytic systems developed in recent years. Particular emphasis is placed on those involving discrete complexes through their structure and catalytic performance, in terms of both activity and selectivity (when relevant) as well as their limitations.
2020, 83(5): 418-426
Abstract:
The development of rapid detection technology for harmful substances in food is of great significance to food safety and national health. As a kind of nanoparticle with extraordinary photoelectric properties, quantum dots have been widely used in the field of food safety rapid detection in recent years. In this paper, the detection mechanism of quantum dot visualization sensor, its detection of harmful substances such as pesticide, veterinary drug and heavy metals in food, and the non-target detection of illegal food addition were reviewed. The existing problems and future developments were also discussed.
The development of rapid detection technology for harmful substances in food is of great significance to food safety and national health. As a kind of nanoparticle with extraordinary photoelectric properties, quantum dots have been widely used in the field of food safety rapid detection in recent years. In this paper, the detection mechanism of quantum dot visualization sensor, its detection of harmful substances such as pesticide, veterinary drug and heavy metals in food, and the non-target detection of illegal food addition were reviewed. The existing problems and future developments were also discussed.
2020, 83(5): 427-433
Abstract:
Microplastics are difficult to degrade in the environment, they can exist for a long time in water and sediments, and can accumulate in aquatic organisms, which has become one of the environmental issues that have attracted great concern. Rapid, efficient and accurate detection technology is an important part of the research on microplastics in the water environment, which is crucial for optimizing the research route, analyzing the research results and summarizing the law of microplastics pollution. In this paper, combining with microplastic pollution research progress at home and abroad, the current situation of microplastic pollution, the methods for sampling, pretreatment, and qualitative and quantitative analysis of microplastics in environmental samples are introduced, and the advantages and disadvantages of current detection methods and their respective application range are summarized, finally, the direction of further research is pointed out.
Microplastics are difficult to degrade in the environment, they can exist for a long time in water and sediments, and can accumulate in aquatic organisms, which has become one of the environmental issues that have attracted great concern. Rapid, efficient and accurate detection technology is an important part of the research on microplastics in the water environment, which is crucial for optimizing the research route, analyzing the research results and summarizing the law of microplastics pollution. In this paper, combining with microplastic pollution research progress at home and abroad, the current situation of microplastic pollution, the methods for sampling, pretreatment, and qualitative and quantitative analysis of microplastics in environmental samples are introduced, and the advantages and disadvantages of current detection methods and their respective application range are summarized, finally, the direction of further research is pointed out.
2020, 83(5): 434-441
Abstract:
Structure of liquid water in the temperature range of 298~373 K was studied by neutron and X-ray scattering. The influences of temperature on the structure of liquid water were discussed in terms of partial radial distribution function (PDF), coordination number distribution (CN), angular distribution function (ADF) and spatial density function (SDF). Liquid water possesses a short-range ordered, "Irregular tetrahedron" hydrogen-bonded network structure, which extends to the third sphere. Around 4.8 water molecules run into the first sphere of liquid water, but only about 3.3 of them bond with the central water molecule. About 1/3 of the water molecules act as the interstitial water, which enters the first layer but does not directly bond with the central water molecule. It is the presence of these interstitial water molecules that aggravates the complexity of the structure of liquid water. High temperature disturbs the structure of liquid water to a certain extent. From 298 K to 373 K, the O(W)…O(W) distance increases by 0.03Å, the number of hydrogen bonds decreases by 0.1, and the ∠O(W)…O(W)…O(W) angle distribution widens. In the limited temperature range of 298~373 K in the present work, the temperature effects are slight in the SDF for the first sphere, while much more significant effect is observed for the second and the third spheres.
Structure of liquid water in the temperature range of 298~373 K was studied by neutron and X-ray scattering. The influences of temperature on the structure of liquid water were discussed in terms of partial radial distribution function (PDF), coordination number distribution (CN), angular distribution function (ADF) and spatial density function (SDF). Liquid water possesses a short-range ordered, "Irregular tetrahedron" hydrogen-bonded network structure, which extends to the third sphere. Around 4.8 water molecules run into the first sphere of liquid water, but only about 3.3 of them bond with the central water molecule. About 1/3 of the water molecules act as the interstitial water, which enters the first layer but does not directly bond with the central water molecule. It is the presence of these interstitial water molecules that aggravates the complexity of the structure of liquid water. High temperature disturbs the structure of liquid water to a certain extent. From 298 K to 373 K, the O(W)…O(W) distance increases by 0.03Å, the number of hydrogen bonds decreases by 0.1, and the ∠O(W)…O(W)…O(W) angle distribution widens. In the limited temperature range of 298~373 K in the present work, the temperature effects are slight in the SDF for the first sphere, while much more significant effect is observed for the second and the third spheres.
2020, 83(5): 442-447
Abstract:
A coumarin-based fluorescent probe (compound 1) for Pd2+ has been designed and synthesized. Compound 1 consists of a coumarin and a carboxymethyl hydroxylamine moiety which can detect Pd2+ in pure water with high selectivity and sensitivity. The detection limit of the probe was as low as 4.0×10-8 mol/L. The probe can effectively detect Pd2+ in the pH range of 4~9.
A coumarin-based fluorescent probe (compound 1) for Pd2+ has been designed and synthesized. Compound 1 consists of a coumarin and a carboxymethyl hydroxylamine moiety which can detect Pd2+ in pure water with high selectivity and sensitivity. The detection limit of the probe was as low as 4.0×10-8 mol/L. The probe can effectively detect Pd2+ in the pH range of 4~9.
2020, 83(5): 448-452
Abstract:
A coumarin-based fluorescent probe L was synthesized. Its structure was characterized by NMR and MS. The probe has high selectivity and sensitivity towards Co2+ and Ni2+ in DMSO/water (v/v=9:1) solvent. Upon the addition of Co2+ or Ni2+, the probe L displayed remarkable fluorescence quenching, which could not be interfered by other metal ions. The results showed that the coordination ratio of probe L to Co2+ and Ni2+ is 1:2. The detection limits for Co2+ and for Ni2+ are 1.002×10-7mol/L and 9.78×10-6mol/L, and the binding constants are 1.06×106 L·mol-1 and 9.84×105L·mol-1, respectively.
A coumarin-based fluorescent probe L was synthesized. Its structure was characterized by NMR and MS. The probe has high selectivity and sensitivity towards Co2+ and Ni2+ in DMSO/water (v/v=9:1) solvent. Upon the addition of Co2+ or Ni2+, the probe L displayed remarkable fluorescence quenching, which could not be interfered by other metal ions. The results showed that the coordination ratio of probe L to Co2+ and Ni2+ is 1:2. The detection limits for Co2+ and for Ni2+ are 1.002×10-7mol/L and 9.78×10-6mol/L, and the binding constants are 1.06×106 L·mol-1 and 9.84×105L·mol-1, respectively.
2020, 83(5): 453-458
Abstract:
Composite phase change material AC/PW, AC/PA and AC/SA were prepared by melt blending using activated carbon (AC) as supporting material and paraffin (PW), palmitic acid (PA) and stearic acid (SA) as main phase change materials, and their thermal and electrical properties were studied by infrared thermal imager, thermal conduction coefficient and powder semi-conductor resistance tester. The results showed that organic matter will not leak when activated carbon is added, and the temperature field distribution during the charging and exothermic process of the composite is relatively uniform. Thermal cycling will slightly reduce the thermal conductivity of the material. In addition, the electrical resistivity of the three composite materials decreases with the increase of pressure.
Composite phase change material AC/PW, AC/PA and AC/SA were prepared by melt blending using activated carbon (AC) as supporting material and paraffin (PW), palmitic acid (PA) and stearic acid (SA) as main phase change materials, and their thermal and electrical properties were studied by infrared thermal imager, thermal conduction coefficient and powder semi-conductor resistance tester. The results showed that organic matter will not leak when activated carbon is added, and the temperature field distribution during the charging and exothermic process of the composite is relatively uniform. Thermal cycling will slightly reduce the thermal conductivity of the material. In addition, the electrical resistivity of the three composite materials decreases with the increase of pressure.
2020, 83(5): 459-463
Abstract:
The densities of NaCl-KCl aqueous mixture were determined at temperatures from 288.15 to 323.15 K and over a range of composition at ionic strength of 0.1~4 mol·kg-1. A high precision vibrating-tube densitometer was used in the measurement. The excess volumes of the mixed electrolytes calculated from the experimental data permitted a parameterization of the Pitzer model for mixtures with the entire range of temperatures and compositions covered by this study. In addition, using the Pitzer model, we determined the volume of mixing at constant ionic strength and at 298.15 K.
The densities of NaCl-KCl aqueous mixture were determined at temperatures from 288.15 to 323.15 K and over a range of composition at ionic strength of 0.1~4 mol·kg-1. A high precision vibrating-tube densitometer was used in the measurement. The excess volumes of the mixed electrolytes calculated from the experimental data permitted a parameterization of the Pitzer model for mixtures with the entire range of temperatures and compositions covered by this study. In addition, using the Pitzer model, we determined the volume of mixing at constant ionic strength and at 298.15 K.
2020, 83(5): 464-471
Abstract:
The magnetic properties was studied for a series of {GdIIIMII}(M=Cu, Ni, Co, Fe, Mn) heterobinuclear complexes by the combination of DFT calculations, using the different functional methods and basis sets, with the broken-symmetry approach. The results showed that the calculated values at the level of PBE0/TZVP (Gd is SARC-ZDRA-TZVP) are consistent with the experimental values, and this method can be used to describe its magnetic properties. There is a strong orbital interaction between the paramagnetic centers CuII and GdIII and bridged coordination oxygen atoms. The molecular magnetic orbital of the complex[CuIIGdIII{PyCO(OEt)Py C(OH)(OEt)Py}3]2+ are mainly contributed by 4fz3, 4fz(x2-y2) orbitals of the paramagnetic center GdIII, 3dx2-y2 orbital of CuII ion and p orbitals of the bridging oxygen atoms. Due to the compensation of spin delocalization from CuII ion and spin polarization from GdIII ion, the effect of spin delocalization from CuII ion on bridged oxygen atoms is greater than the spin polarization effect of paramagnetic center GdIII ion. Model calculations were used to examine the influence of the electronic configuration of the MII ions on the magnetic coupling constants. As a result, the increase of unpaired electrons of MII ions, the ρHS2-ρBS2 of the paramagnetic centers GdIII/MIIincreases, the contribution of antiferromagnetic coupling increases, whereas the values of the magnetic coupling constant decreases.
The magnetic properties was studied for a series of {GdIIIMII}(M=Cu, Ni, Co, Fe, Mn) heterobinuclear complexes by the combination of DFT calculations, using the different functional methods and basis sets, with the broken-symmetry approach. The results showed that the calculated values at the level of PBE0/TZVP (Gd is SARC-ZDRA-TZVP) are consistent with the experimental values, and this method can be used to describe its magnetic properties. There is a strong orbital interaction between the paramagnetic centers CuII and GdIII and bridged coordination oxygen atoms. The molecular magnetic orbital of the complex[CuIIGdIII{PyCO(OEt)Py C(OH)(OEt)Py}3]2+ are mainly contributed by 4fz3, 4fz(x2-y2) orbitals of the paramagnetic center GdIII, 3dx2-y2 orbital of CuII ion and p orbitals of the bridging oxygen atoms. Due to the compensation of spin delocalization from CuII ion and spin polarization from GdIII ion, the effect of spin delocalization from CuII ion on bridged oxygen atoms is greater than the spin polarization effect of paramagnetic center GdIII ion. Model calculations were used to examine the influence of the electronic configuration of the MII ions on the magnetic coupling constants. As a result, the increase of unpaired electrons of MII ions, the ρHS2-ρBS2 of the paramagnetic centers GdIII/MIIincreases, the contribution of antiferromagnetic coupling increases, whereas the values of the magnetic coupling constant decreases.
2020, 83(5): 472-475
Abstract:
Using hydrotalcite supported iodine (I2/LDHs) as catalyst, aromatic aldehyde, aromatic amine and trimethylsilycyanide (TMSCN) as raw material, 10 kinds of alpha amino acrylic derivatives were synthesized, and their structures are confirmed by 1H NMR. Under the optimum reaction conditions:nbenzaldehyde:naniline:nTMSCN=1.0:1.0:1.4, hydrotalcite supported iodine (10(mol)%) as catalyst, methanol as solvent, and stirred for 10 minutes. The highest yield of α-aminonitriles can reach 98.3%.
Using hydrotalcite supported iodine (I2/LDHs) as catalyst, aromatic aldehyde, aromatic amine and trimethylsilycyanide (TMSCN) as raw material, 10 kinds of alpha amino acrylic derivatives were synthesized, and their structures are confirmed by 1H NMR. Under the optimum reaction conditions:nbenzaldehyde:naniline:nTMSCN=1.0:1.0:1.4, hydrotalcite supported iodine (10(mol)%) as catalyst, methanol as solvent, and stirred for 10 minutes. The highest yield of α-aminonitriles can reach 98.3%.
2020, 83(5): 476-479
Abstract:
The range of abrupt change in the titration curve plays a key role in selecting an indicator, and also is the important factor to determine whether or not the titration proceeds accurately. Before the stoichiometric point of the chemical reaction, the approximate formula\begin{document}$\mathrm{pH}=\mathrm{p} K_{\mathrm{a}}+\lg \frac{c_{\mathrm{B}^{-}}}{c_{\mathrm{HB}}} $\end{document} \begin{document}$\left[\mathrm{H}^{+}\right]=\frac{10^{-3} c K_{\mathrm{a}}}{c+2 K_{\mathrm{a}}} $\end{document} \begin{document}$\left[\mathrm{H}^{+}\right]=\frac{\left.c K_{\mathrm{a}}+\sqrt{c K_{\mathrm{a}}\left(c K_{\mathrm{a}}+8 \times 10^{-8}\right)}\right)}{2000 c} $\end{document} \begin{document}$ \left[\mathrm{H}^{+}\right]=\frac{\left.-c K_{\mathrm{a}}+\sqrt{c K_{\mathrm{a}}\left(c K_{\mathrm{a}}+8 \times 10^{-8}\right)}\right)}{2000 c} $\end{document} \begin{document}$ \mathrm{pH}=\mathrm{p} K_{\mathrm{a}}+\lg \frac{c_{\mathrm{B}}-}{c_{\mathrm{H} \mathrm{B}}}$\end{document}
The range of abrupt change in the titration curve plays a key role in selecting an indicator, and also is the important factor to determine whether or not the titration proceeds accurately. Before the stoichiometric point of the chemical reaction, the approximate formula
