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1983 Volume 1 Issue 1
1983, 1(1): 1-14
Abstract:
The present review aims at summarizing the ways by which dioxygen can be activated under mild conditions, as well as the reactions concerning various activated oxygen species including its protonated products. The emphasis is placed on two ways for molecular oxygen to activate. The one relating to the requirement of a transition metal ion as a catalyst and the other referring to the formation of a highly resonance stabilized radical as an intermediate.
The present review aims at summarizing the ways by which dioxygen can be activated under mild conditions, as well as the reactions concerning various activated oxygen species including its protonated products. The emphasis is placed on two ways for molecular oxygen to activate. The one relating to the requirement of a transition metal ion as a catalyst and the other referring to the formation of a highly resonance stabilized radical as an intermediate.
1983, 1(1): 15-21
Abstract:
Since the coordination number of lanthanides is usually 8 or more, it is quite difficult to prepare the hexa-coordinated rare earth complexes of pyrazolone of composition REA3·Recently Roy[4] and Okafor[5] reported the synthesis of 8 rare earth complexes of the title ligand and it was said which had the composition of REA3·We have repeated their experiments many times, but the products obtained and very carefully characterized always remained REA3·HA. In the present investigation, we have synthesized 15 REA3·CeA4 and 15 REA3·2H3O complexes by a new procedure, and also 14 REA3·HA complexes. The composition of these 45 complexes was carefully characterized by elemental analysis, Fourier transform infraredspectra in the far and middle infrared range and NMR studies. Among these 45 compounds, 30 have not been reported previously.
Since the coordination number of lanthanides is usually 8 or more, it is quite difficult to prepare the hexa-coordinated rare earth complexes of pyrazolone of composition REA3·Recently Roy[4] and Okafor[5] reported the synthesis of 8 rare earth complexes of the title ligand and it was said which had the composition of REA3·We have repeated their experiments many times, but the products obtained and very carefully characterized always remained REA3·HA. In the present investigation, we have synthesized 15 REA3·CeA4 and 15 REA3·2H3O complexes by a new procedure, and also 14 REA3·HA complexes. The composition of these 45 complexes was carefully characterized by elemental analysis, Fourier transform infraredspectra in the far and middle infrared range and NMR studies. Among these 45 compounds, 30 have not been reported previously.
1983, 1(1): 22-27
Abstract:
Cis-1,4-polybutadiene rubber with vinyl content ranging from 7 to 16% in a form of syndiotactic-1,2-polybutadiene blocks was synthesized with cobalt catalyst systems through two-stage polymerization. The polymer obtained has been characterized by their solubility behavior, infrared spectrum, X-ray diffraction patterns, incipient crystallization temperature and half crystallization time.
Cis-1,4-polybutadiene rubber with vinyl content ranging from 7 to 16% in a form of syndiotactic-1,2-polybutadiene blocks was synthesized with cobalt catalyst systems through two-stage polymerization. The polymer obtained has been characterized by their solubility behavior, infrared spectrum, X-ray diffraction patterns, incipient crystallization temperature and half crystallization time.
1983, 1(1): 28-32
Abstract:
A new water-soluble polymeric selective chelating agent for mercury(Ⅱ) was prepared by the acid mercaptalation of the aldehyde derivative of dextran with ethylene glycol dithioglycolate. The product is composed of macrocyclic mercaptal groups linked to dextran. A preliminary examination of its acute toxicity and its ability to offset-acute mercuric chloride poisoning has been made. The results indicate that this chelating agent is relatively non-toxic and improves the survival rate of animals.It seems promising as an oral agent for the treatment of mercury poisoning and should be able to remove mercury from the enterohepatic circulation and increase its rate of excretion via the feces and urine.
A new water-soluble polymeric selective chelating agent for mercury(Ⅱ) was prepared by the acid mercaptalation of the aldehyde derivative of dextran with ethylene glycol dithioglycolate. The product is composed of macrocyclic mercaptal groups linked to dextran. A preliminary examination of its acute toxicity and its ability to offset-acute mercuric chloride poisoning has been made. The results indicate that this chelating agent is relatively non-toxic and improves the survival rate of animals.It seems promising as an oral agent for the treatment of mercury poisoning and should be able to remove mercury from the enterohepatic circulation and increase its rate of excretion via the feces and urine.
1983, 1(1): 33-39
Abstract:
The crystal of gadolinium pentaphosphate belongs to the monoclinic system.The space group is P21/a.The crystal parameters are a=12.910(9), b=8.889(10), c=8.721 (6)Å, β=90.53, z=4. The diffraction data have been collected by using PW-1100Four-Circle Diffractometer. The total number of independent diffraction amounts to 2012. The structure has been solved by heavyatom method, and the structure parameters have been refined by means of full matrix and block-diagonal least square method, R=0.103. The result of structure analysis indicated that the coordination number of gadolinium cation is eight,Gd-Gd distance is 5.902Å.
The crystal of gadolinium pentaphosphate belongs to the monoclinic system.The space group is P21/a.The crystal parameters are a=12.910(9), b=8.889(10), c=8.721 (6)Å, β=90.53, z=4. The diffraction data have been collected by using PW-1100Four-Circle Diffractometer. The total number of independent diffraction amounts to 2012. The structure has been solved by heavyatom method, and the structure parameters have been refined by means of full matrix and block-diagonal least square method, R=0.103. The result of structure analysis indicated that the coordination number of gadolinium cation is eight,Gd-Gd distance is 5.902Å.
1983, 1(1): 40-46
Abstract:
We derived a method for the calculation of complex chemical equilibria by using the independent components. The number of unknowns and the number of independent equations for this method are obviously less than those used in the method for the minimization of free energy, the method for the mass action equations and the method based on calculating extents of reactions. By this simple method a pocket programmable calculator e. g. TI-59 is sufficient to calculate a complex chemical equilibrium system containing three elements which form 10 chemical components but for the same system a computer must be used by other methods. The basic principle and concrete procedure of the method are presented in this paper. The superiority of the method to others according to theoretical consideration and computing practice is also discussed.
We derived a method for the calculation of complex chemical equilibria by using the independent components. The number of unknowns and the number of independent equations for this method are obviously less than those used in the method for the minimization of free energy, the method for the mass action equations and the method based on calculating extents of reactions. By this simple method a pocket programmable calculator e. g. TI-59 is sufficient to calculate a complex chemical equilibrium system containing three elements which form 10 chemical components but for the same system a computer must be used by other methods. The basic principle and concrete procedure of the method are presented in this paper. The superiority of the method to others according to theoretical consideration and computing practice is also discussed.
1983, 1(1): 47-54
Abstract:
The effect of phosphoric acid on extraction separation of rare earth(Ⅲ)and iron(Ⅲ)from sulphuric acid solution by primary amine N1923 was investigated.The behavior of different primary amine and solvent or temperatures in dependence on the extraction seperation of rare earth(Ⅲ)was studied.The mechanism of iron(Ⅲ)extraction from phosphciic acid solution was proposed.The IR study was carried out for the organic phase.
The effect of phosphoric acid on extraction separation of rare earth(Ⅲ)and iron(Ⅲ)from sulphuric acid solution by primary amine N1923 was investigated.The behavior of different primary amine and solvent or temperatures in dependence on the extraction seperation of rare earth(Ⅲ)was studied.The mechanism of iron(Ⅲ)extraction from phosphciic acid solution was proposed.The IR study was carried out for the organic phase.
1983, 1(1): 55-57
Abstract:
The dicyclopentadienyl neodymium chloride(C5H5)2 NdCI·THF was prepared by the reaction of NdCl3·2THF(0.002mole)with cyclopentadienyl sodium(0.0036mole) in tetrahydrofuran(THF)at room temperature. The existence of the titled compound was verified by the data of elemental analysis, infrared spectroscopy and photoelectron spectroscopy. On heating under vacuum the THF in (C5H5)2 NdCl·THF was removed and a light-purple residue was obtained. Its composition is in agreement with a formulation as(C5H5)2 NdCl.
The dicyclopentadienyl neodymium chloride(C5H5)2 NdCI·THF was prepared by the reaction of NdCl3·2THF(0.002mole)with cyclopentadienyl sodium(0.0036mole) in tetrahydrofuran(THF)at room temperature. The existence of the titled compound was verified by the data of elemental analysis, infrared spectroscopy and photoelectron spectroscopy. On heating under vacuum the THF in (C5H5)2 NdCl·THF was removed and a light-purple residue was obtained. Its composition is in agreement with a formulation as(C5H5)2 NdCl.
1983, 1(1): 58-65
Abstract:
This paper reports our work on low-temperature transitions of random copolymer of butadiene and isoprene prepared with rare-earth catalyst.It is shown by experiments that the glass transition temperature, the crystallization rate and the maximum main crystallization value of these copolymers vary with monomer ratio in the copolymer.When the weight ratio of buta-diene/isoprene reaches 84/16, the copolymer becomes noncrystallizable rubber. The maximum crystallzation rate temperature, Tcmax, of polybutadiene prepared with rare-earth catalyst was obtained as-72℃ by extrapolation of the experimental data of copolymer with various monomer ratio,which has not been reported in literature. The glass temperature,Tg of polybutadiene prepared with rare-earth catalyst is-113℃.The ratio of Tcmax(°K)/Tg(°K) is equal to 0.796,and that of natural rubber equals 201/247=0.814,both are close to 0.80.
This paper reports our work on low-temperature transitions of random copolymer of butadiene and isoprene prepared with rare-earth catalyst.It is shown by experiments that the glass transition temperature, the crystallization rate and the maximum main crystallization value of these copolymers vary with monomer ratio in the copolymer.When the weight ratio of buta-diene/isoprene reaches 84/16, the copolymer becomes noncrystallizable rubber. The maximum crystallzation rate temperature, Tcmax, of polybutadiene prepared with rare-earth catalyst was obtained as-72℃ by extrapolation of the experimental data of copolymer with various monomer ratio,which has not been reported in literature. The glass temperature,Tg of polybutadiene prepared with rare-earth catalyst is-113℃.The ratio of Tcmax(°K)/Tg(°K) is equal to 0.796,and that of natural rubber equals 201/247=0.814,both are close to 0.80.
1983, 1(1): 66-72
Abstract:
The solubility of the ternary system, Y(NO3)3·3H2O-B15C5-CH3COCH3at 18℃ has been determined by a phase equilibrium method. The results indicated that there are two solubility curves for the system, the long one correspounds with the solid phase of the complex,Y(NO3)3·B15C5·3H2O 2.5CH3COCH3 and the short one with that of B15C5. There was a failure to achieve other complex species with another Y/crown ratios. The behavior of water for this system in equilibrium has been examined. The results are:the mole ratio,((H2O)/(Y(NO3)3)), no matter whether it is in liquid phase or solid phase, is always 3:1. The composition of the isolated complex have been examined by chemical anaiysis, infrared spectra and thermogravimetric analysis,as well as the relation between the composition of complexes and after treament conditions. A relatively stable complex,Y(NO3)3. B15C5·3H2O·0.65CH3COCH3 was obtained.
The solubility of the ternary system, Y(NO3)3·3H2O-B15C5-CH3COCH3at 18℃ has been determined by a phase equilibrium method. The results indicated that there are two solubility curves for the system, the long one correspounds with the solid phase of the complex,Y(NO3)3·B15C5·3H2O 2.5CH3COCH3 and the short one with that of B15C5. There was a failure to achieve other complex species with another Y/crown ratios. The behavior of water for this system in equilibrium has been examined. The results are:the mole ratio,((H2O)/(Y(NO3)3)), no matter whether it is in liquid phase or solid phase, is always 3:1. The composition of the isolated complex have been examined by chemical anaiysis, infrared spectra and thermogravimetric analysis,as well as the relation between the composition of complexes and after treament conditions. A relatively stable complex,Y(NO3)3. B15C5·3H2O·0.65CH3COCH3 was obtained.
1983, 1(1): 73-78
Abstract:
The morphology and the composition of the hard incrustation stuck on the inner wall of pipeline and the water residue have been studied using methods of x-ray diffraction analysis,scanning electron microscope, chemical analysis, etc.. It was found that the incrustation had a preffered orientation and might be considered as a large crystal of CaCO3 with a lot of defects and inclusions in it.The method of vigorous stirring the dusty water with forced water stream is often used in order to prevent the formation of the incrustation.It was found that under such conditions the pH would become greater than 11 and a lot of small crystals of CaCO3 will be formed quickly due to the common ion effect, at the same time the amorphous Mg(OH)2 is precipited, which being adhered to the surfaces of the small crystals will stop the further growth of CaCO3 crystal. As a result, the orientation of the small crystals becomes impossible and a loose water residue remains,which can be taken away easily by forced running water.
The morphology and the composition of the hard incrustation stuck on the inner wall of pipeline and the water residue have been studied using methods of x-ray diffraction analysis,scanning electron microscope, chemical analysis, etc.. It was found that the incrustation had a preffered orientation and might be considered as a large crystal of CaCO3 with a lot of defects and inclusions in it.The method of vigorous stirring the dusty water with forced water stream is often used in order to prevent the formation of the incrustation.It was found that under such conditions the pH would become greater than 11 and a lot of small crystals of CaCO3 will be formed quickly due to the common ion effect, at the same time the amorphous Mg(OH)2 is precipited, which being adhered to the surfaces of the small crystals will stop the further growth of CaCO3 crystal. As a result, the orientation of the small crystals becomes impossible and a loose water residue remains,which can be taken away easily by forced running water.
1983, 1(1): 79-86
Abstract:
A new "family" of coordination catalysts based on rare-earth for stereos-pecific polymerization of acetylene has been developed for the preparation of high cis(90%) polyacetylene(PA) films at 30℃. Rare-earth PA was silvery flexible with metallic luster. The highly conducting complexes of rare-earth PA are obtained by do poing with electron acceptors(I2,Br2,etc.). The maximum conductivity(σ) of doped films at room temperature is approximately 1000 ohm-1·cm-1 for iodine,corresponding to a concentration of about 12.5 mol% where σ has increased by some 11 orders of magnitude. The doping effect is related to the volume filling fraction of the fibrils of PA.The configuration of polymer and the extent of oxidation of the films also show a certain influences on the doping effect. The resulted polyacetylenehalogen complexes have been characterized using techniques of infrared spectrophotometry, differential scanning calorimetry,x-ray diffraction,scanning electron micrography,and electrical conductivity measurements.
A new "family" of coordination catalysts based on rare-earth for stereos-pecific polymerization of acetylene has been developed for the preparation of high cis(90%) polyacetylene(PA) films at 30℃. Rare-earth PA was silvery flexible with metallic luster. The highly conducting complexes of rare-earth PA are obtained by do poing with electron acceptors(I2,Br2,etc.). The maximum conductivity(σ) of doped films at room temperature is approximately 1000 ohm-1·cm-1 for iodine,corresponding to a concentration of about 12.5 mol% where σ has increased by some 11 orders of magnitude. The doping effect is related to the volume filling fraction of the fibrils of PA.The configuration of polymer and the extent of oxidation of the films also show a certain influences on the doping effect. The resulted polyacetylenehalogen complexes have been characterized using techniques of infrared spectrophotometry, differential scanning calorimetry,x-ray diffraction,scanning electron micrography,and electrical conductivity measurements.
1983, 1(1): 87-93
Abstract:
The anodic reaction of oxygen evolution on PbO2 electrode was studied by A. C. impedance measurement. The Faradaic. resistance Rt,double layer capacitance Cd adsorption resistance Ra and adsorption capacitance Ca were determined by analyzing the impedance spectra with microcomputer curve-fitting method. The rate-controlling step of the reaction was considered to be (OH)ad+H2O→(O)ad+H3O+e-1. The relation between Cd, Ca.and OH-1 ion concentration was discussed in view of the adsorption effect.
The anodic reaction of oxygen evolution on PbO2 electrode was studied by A. C. impedance measurement. The Faradaic. resistance Rt,double layer capacitance Cd adsorption resistance Ra and adsorption capacitance Ca were determined by analyzing the impedance spectra with microcomputer curve-fitting method. The rate-controlling step of the reaction was considered to be (OH)ad+H2O→(O)ad+H3O+e-1. The relation between Cd, Ca.and OH-1 ion concentration was discussed in view of the adsorption effect.
1983, 1(1): 94-98
Abstract:
We have studied the effects of polymerization conditions on the product structures and emphasized the ESCA characterization of PPTFE film formed in nonglow region. The results have shown the formation of a nearly-linear PPTFE in nonglow region. It has been found that the X-ray diffraction patterns of the PPTFE formed in this region are similar to those of chemically formed PTEE, which exibit about 20 diffraction rings. The effects of discharge power, pressure and plasma gases on the structure of polymer film shave also been examined.
We have studied the effects of polymerization conditions on the product structures and emphasized the ESCA characterization of PPTFE film formed in nonglow region. The results have shown the formation of a nearly-linear PPTFE in nonglow region. It has been found that the X-ray diffraction patterns of the PPTFE formed in this region are similar to those of chemically formed PTEE, which exibit about 20 diffraction rings. The effects of discharge power, pressure and plasma gases on the structure of polymer film shave also been examined.
1983, 1(1): 99-102
Abstract:
Highly conductive and transparent thin films of indium-tin-oxide(ITO)have been prepared by a simple pyrolitic (spray) method. The conditions of preparation were described. Highly transparent (80-98% transmission) ITO films were obtained with sheet resistances of approximately 2-5Ω/口 for glass substrates and 6Ω/口 for borosilicate glass substrates.
Highly conductive and transparent thin films of indium-tin-oxide(ITO)have been prepared by a simple pyrolitic (spray) method. The conditions of preparation were described. Highly transparent (80-98% transmission) ITO films were obtained with sheet resistances of approximately 2-5Ω/口 for glass substrates and 6Ω/口 for borosilicate glass substrates.
1983, 1(1): 103-107
Abstract:
Using a photoacoustic spectrometer model GS-1 we have obtained the solid state photo acoustic spectra of 14 rare earth oxides (except the one for radioactive promethium). These spectra are in good agreement with corresponding diffusion reflectance spectra, but the photo acoustic measurementis simpler.
Using a photoacoustic spectrometer model GS-1 we have obtained the solid state photo acoustic spectra of 14 rare earth oxides (except the one for radioactive promethium). These spectra are in good agreement with corresponding diffusion reflectance spectra, but the photo acoustic measurementis simpler.
1983, 1(1): 108-111
Abstract:
1983, 1(1): 112-115
Abstract:
