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1984 Volume 1 Issue 2
1984, 1(2): 1-6
Abstract:
(Sr,Ba)SiO3: Eu3+ was synthesized at high temperature using SrCO3,BaCO3, H2SiO3, Li2CO3 and Eu2(C2O4)3 of A.R.grade. The optical synthesis conditions were achieved through orthogonal design, i.e. 1150℃ and 3 hr. The products with constitution of (Sr0.8Ba0.2)0.95Eu0.025Li0.025SiO3 or Sr0.95Eu0.025Li0.25SiO3 show the greatest intensity of illumination. The property of the product has been studied by means of x-ray powder diffraction, laser fluorescence and illuminant spectroscopy.
(Sr,Ba)SiO3: Eu3+ was synthesized at high temperature using SrCO3,BaCO3, H2SiO3, Li2CO3 and Eu2(C2O4)3 of A.R.grade. The optical synthesis conditions were achieved through orthogonal design, i.e. 1150℃ and 3 hr. The products with constitution of (Sr0.8Ba0.2)0.95Eu0.025Li0.025SiO3 or Sr0.95Eu0.025Li0.25SiO3 show the greatest intensity of illumination. The property of the product has been studied by means of x-ray powder diffraction, laser fluorescence and illuminant spectroscopy.
1984, 1(2): 7-12
Abstract:
The esterifications of hydroxy——terminated liquid polymers, such as liquid tetrahydrofuran——propylene oxide copolymer,with maleic anhydride were investigated and carboxyl-vinylene-terminated liquid copolymers were obtained. Under certain conditions,such as reaction temperature,feed ratio and with suitable catalysts, 100% conversion of terminal groups has been achie-ved. The degree of terminal group conversion and the structure of the po-lymers were determined by chemical titration,IR and 1H-NMR, respecti-vely.
The esterifications of hydroxy——terminated liquid polymers, such as liquid tetrahydrofuran——propylene oxide copolymer,with maleic anhydride were investigated and carboxyl-vinylene-terminated liquid copolymers were obtained. Under certain conditions,such as reaction temperature,feed ratio and with suitable catalysts, 100% conversion of terminal groups has been achie-ved. The degree of terminal group conversion and the structure of the po-lymers were determined by chemical titration,IR and 1H-NMR, respecti-vely.
1984, 1(2): 13-18
Abstract:
The effects of heavy——atom compounds and atmospheres on the opticaldevel opment rate of CBr4-LCV (Leuco Crystal Violet) free radical film have been studied. It was found that the development rate is. increased in the presence of heavy-atom compounds:CHI3, p-iodoaniline and triphenyl-bismuth in the film or the optical development proceeds in nitrogen and is decreased when the film is developed in oxygen, indicating the possibi-lity of T-T energy transfer mechanism. The ratio of rate constant K0 innitrogen to K in the mixture of N2/O2 follows the equation K0/K=1+α[O2] where α is the quenching constant. In the main period of the optical development the following relation-ship between optical density(D) and time(t) is also found to be existed D=D0+Kt, where D0 is the experimental constant, K and t are the optical development rate constant and time, respectively.
The effects of heavy——atom compounds and atmospheres on the opticaldevel opment rate of CBr4-LCV (Leuco Crystal Violet) free radical film have been studied. It was found that the development rate is. increased in the presence of heavy-atom compounds:CHI3, p-iodoaniline and triphenyl-bismuth in the film or the optical development proceeds in nitrogen and is decreased when the film is developed in oxygen, indicating the possibi-lity of T-T energy transfer mechanism. The ratio of rate constant K0 innitrogen to K in the mixture of N2/O2 follows the equation K0/K=1+α[O2] where α is the quenching constant. In the main period of the optical development the following relation-ship between optical density(D) and time(t) is also found to be existed D=D0+Kt, where D0 is the experimental constant, K and t are the optical development rate constant and time, respectively.
1984, 1(2): 19-23
Abstract:
Based on the x-ray scattering intensity theory, the correction factors of crystallinity formulae of polymers have been clearly defined. The cry-stallinity formulae of the cis-1,4 PB was derived in terms of the WAXD curves of polymers by graphic multipeak resolution methods. The crystal-linity of other crystalline polymers can be easily evaluated by our method.
Based on the x-ray scattering intensity theory, the correction factors of crystallinity formulae of polymers have been clearly defined. The cry-stallinity formulae of the cis-1,4 PB was derived in terms of the WAXD curves of polymers by graphic multipeak resolution methods. The crystal-linity of other crystalline polymers can be easily evaluated by our method.
1984, 1(2): 24-28
Abstract:
Various physical properties, such as total surface area, iron surface area, alkali surface area, density, pore size distribution etc. of A110-5Q spherical catalyst for ammonia synthesis have been studied using electron-microscope, thermogravimeter and Mosbauer spectroscopy. Porosity, void fraction and specific pore volume of the catalyst were calculated. The ca-talyst is characterized by its high activity at low temperature, fine gra-ined crystal and easier reducibility.
Various physical properties, such as total surface area, iron surface area, alkali surface area, density, pore size distribution etc. of A110-5Q spherical catalyst for ammonia synthesis have been studied using electron-microscope, thermogravimeter and Mosbauer spectroscopy. Porosity, void fraction and specific pore volume of the catalyst were calculated. The ca-talyst is characterized by its high activity at low temperature, fine gra-ined crystal and easier reducibility.
1984, 1(2): 29-35
Abstract:
In preparing copolymer with homogeneous composition by batch process in two-component copolymerization reaction it is necessary to keep the monomer ratio con-stant by replenishing the fraction of the more reactive monomer.In this paper a calcu-lation method for monomer feeding is derived, which is capable of controlling the composition of cooligomer during the course of reaction.Some cooligomers of acryloni-trile and butadiene with comparatively homogeneous compositions have been preparedusing this replenishing method. The method would be useful for other two-component copolymerization process.
In preparing copolymer with homogeneous composition by batch process in two-component copolymerization reaction it is necessary to keep the monomer ratio con-stant by replenishing the fraction of the more reactive monomer.In this paper a calcu-lation method for monomer feeding is derived, which is capable of controlling the composition of cooligomer during the course of reaction.Some cooligomers of acryloni-trile and butadiene with comparatively homogeneous compositions have been preparedusing this replenishing method. The method would be useful for other two-component copolymerization process.
1984, 1(2): 36-40
Abstract:
2-Ethylhexylphosphonic acid mono(2-ethylhexyl) ester (EHPAEH) is a more effective extractant than D2EHPA for extraction of rare earths.Fifteen solid and solution rare earth-EHPAEH complexes in kerosine have been prepared and their FT-IR spectra have also been studied using a subtraction technique. In the FT-IR subtraction spectra of either the extracted species in the organic phase or the solid complexes, a positive peak and a negative one were observed corresponding to νP=O→M and νP=O respectively, or to νP-O-M and νP-O-H respectively. The variation of νP=O→M, νP-O-M and νO-M (150cm-1) with the atomic number of lanthanides was shown in Fig.5 and Fig.7 for the solid com-plexes. These curves show an obvious "tetrad effect", Y being located be-tween Er and Tm.
2-Ethylhexylphosphonic acid mono(2-ethylhexyl) ester (EHPAEH) is a more effective extractant than D2EHPA for extraction of rare earths.Fifteen solid and solution rare earth-EHPAEH complexes in kerosine have been prepared and their FT-IR spectra have also been studied using a subtraction technique. In the FT-IR subtraction spectra of either the extracted species in the organic phase or the solid complexes, a positive peak and a negative one were observed corresponding to νP=O→M and νP=O respectively, or to νP-O-M and νP-O-H respectively. The variation of νP=O→M, νP-O-M and νO-M (150cm-1) with the atomic number of lanthanides was shown in Fig.5 and Fig.7 for the solid com-plexes. These curves show an obvious "tetrad effect", Y being located be-tween Er and Tm.
1984, 1(2): 41-45
Abstract:
The complex constants (K) of acrylonitrile, methyl acrylate, methyl methacrylate and butyl methacrylate with ethylaluminium sesquichloride have been evaluated by UV spectrum method.They are dependent upon the e values of acrylic monomers;K=27.5 exp (1.39e) and have the values of 123, 82.6, 50 and 17.5 l/mole, respectively. The rates of alternating copolymerization of acrylic monomers with conjugated dienes in the presence of ethylaluminium sesquichloride in-crease with increasing K and the diffrence of e values between two mono-mers. It is shown that for donor-acceptor monomers the polar effect of mo-nomer plays an important role in the copolymerization.
The complex constants (K) of acrylonitrile, methyl acrylate, methyl methacrylate and butyl methacrylate with ethylaluminium sesquichloride have been evaluated by UV spectrum method.They are dependent upon the e values of acrylic monomers;K=27.5 exp (1.39e) and have the values of 123, 82.6, 50 and 17.5 l/mole, respectively. The rates of alternating copolymerization of acrylic monomers with conjugated dienes in the presence of ethylaluminium sesquichloride in-crease with increasing K and the diffrence of e values between two mono-mers. It is shown that for donor-acceptor monomers the polar effect of mo-nomer plays an important role in the copolymerization.
1984, 1(2): 46-49
Abstract:
Electroreduction of eriochrome red B was studied by d.c.polarography,differential pulse polarography, and cyclic voltammetry. There appeared three waves(peaks) over pH range of 6.2-12.2. The sum of wave Ⅰ,Ⅱ and Ⅲ is of diffusion controlled, two-electron,and irreversible one.Wave Ⅰ and Ⅲ are of adsorption prewave and post-wave,respectively,From experimen-tal results a mechanism for electroreduction of eriochrome red B was pro-posed.
Electroreduction of eriochrome red B was studied by d.c.polarography,differential pulse polarography, and cyclic voltammetry. There appeared three waves(peaks) over pH range of 6.2-12.2. The sum of wave Ⅰ,Ⅱ and Ⅲ is of diffusion controlled, two-electron,and irreversible one.Wave Ⅰ and Ⅲ are of adsorption prewave and post-wave,respectively,From experimen-tal results a mechanism for electroreduction of eriochrome red B was pro-posed.
1984, 1(2): 50-52
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1984, 1(2): 53-55
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1984, 1(2): 56-58
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1984, 1(2): 62-64
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1984, 1(2): 65-68
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