Compared with the conventional Charpy impact test method,the oscillographic impact test can help in the behavioral analysis of materials during the fracture process.In this study,the trade-off relationship between the...Compared with the conventional Charpy impact test method,the oscillographic impact test can help in the behavioral analysis of materials during the fracture process.In this study,the trade-off relationship between the strength and toughness of a DZ2 axle steel at various tempering temperatures and the cause of the improvement in impact toughness was evaluated.The tempering process dramatically influenced carbide precipitation behavior,which resulted in different aspect ratios of carbides.Impact toughness improved along with the rise in tempering temperature mainly due to the increase in energy required in impact crack propagation.The characteristics of the impact crack propagation process were studied through a comprehensive analysis of stress distribution,oscilloscopic impact statistics,fracture morphology,and carbide morphology.The poor impact toughness of low-tempering-temperature specimens was attributed to the increased number of stress concentration points caused by carbide morphology in the small plastic zone during the propagation process,which resulted in a mixed distribution of brittle and ductile fractures on the fracture surface.展开更多
A novel electroanalytical method. oscillographic chronopotentiometry with high and low frequency current. is presented in this paper. With this method, the sensitivity or almost all kinds of oscillographic chronopoten...A novel electroanalytical method. oscillographic chronopotentiometry with high and low frequency current. is presented in this paper. With this method, the sensitivity or almost all kinds of oscillographic chronopotentiometry can be: enhanced about one order.展开更多
A high speed data sampling system on dynamic Oscillographic analysis was established with a 80386DX40 computer, AD 674 and flow injection system. Programs were designed in Microsoft Windows 3.1, that can process E-t, ...A high speed data sampling system on dynamic Oscillographic analysis was established with a 80386DX40 computer, AD 674 and flow injection system. Programs were designed in Microsoft Windows 3.1, that can process E-t, dE/dt-t, i'(f)-t and other kinds of curve on oscillographic analysis. A satisfactory result on determination of Pb2+ and Cd2+ was obtained.展开更多
A new method of oscillographic chronopotentiometry at silver disk electrode was investigated. By using it, a series of ions such as Pb, In, Cr, Tl, Bi etc. were determined. The detection limits are two or three orders...A new method of oscillographic chronopotentiometry at silver disk electrode was investigated. By using it, a series of ions such as Pb, In, Cr, Tl, Bi etc. were determined. The detection limits are two or three orders of magnitude lower than those by oscillographic chronopotentiometry at mercury electrode. The proposed method is characterized by fine sensitivity, stable oscillogram and no mercury. The research on the mechanism of this method shows that these achievements are caused by the characterristics of silver electroxidation and electroreduction and the oscillographic chronopotentiometry (OC).展开更多
A new method called differential reciprocal oscillographic chronopotentiometric titration is presented.It makes use of appearance or disappearance of a peak of depolarizer on differential reciprocal oscillogram indica...A new method called differential reciprocal oscillographic chronopotentiometric titration is presented.It makes use of appearance or disappearance of a peak of depolarizer on differential reciprocal oscillogram indicating the end point of titration.This method was applied to titration of Pb^(2+),Cd^(2+),Ni^(2+),Co^(3+),Zn^(2+),Ga^(3+) and Cu^(2+)by EDTA or EGTA.The end point of titration is very easy to observe and the sensibility of the method is higher than that of diffcrcntial oscillographic chronopotcntiometric titration.展开更多
A small oscillogram, one end of which was substituted by a bright point caused by the redox of an appropriate depolarizer and the other end of which was the redox of Hg or the redox of supporting electrolyte cation, w...A small oscillogram, one end of which was substituted by a bright point caused by the redox of an appropriate depolarizer and the other end of which was the redox of Hg or the redox of supporting electrolyte cation, was investigated in this paper. Experimental results of application of the small oscillogram to oscillographic determination of cefoperazone showed that the small osciUogram was more stable, sensitive, and less interference than classical oscillogram.展开更多
Reciprocal oscillographic chronopotentiogram is such a curve that can converts incisions on "(dE/dt)-E" oscillogram into peaks on "(dt/dE)-E" curve. In order to increase the sensitivity, a new tech...Reciprocal oscillographic chronopotentiogram is such a curve that can converts incisions on "(dE/dt)-E" oscillogram into peaks on "(dt/dE)-E" curve. In order to increase the sensitivity, a new technique called feeding back current was added in new circuit of obtaining reciprocal oscillgraphic chronopotentiogram. It can make capacity current be subtracted easily. Using this method, we carry out studying on principle and titration of drug.展开更多
Under the optimum experimental conditions (i. e., pH=1.6, c KI=10.6 mmol/L, =5.4 mmol/L, =1.30 mmol/L) derived from simplex operations, trace molybdenum(VI) was determined through the agency of its catalytic effect ...Under the optimum experimental conditions (i. e., pH=1.6, c KI=10.6 mmol/L, =5.4 mmol/L, =1.30 mmol/L) derived from simplex operations, trace molybdenum(VI) was determined through the agency of its catalytic effect on the reaction of H2O2 with I? in acid medium. The detection limit and linear calibration range of molybdenum were obtained as 0.5×10?6 mol/L and 0.5×10?6～120×10?6mol/L respectively. This method was applied to the examination of the industrial waste water, and the recovery ratios were found to be in the range of 101% and 107%. Key words oscillographic potentiometry - catalyzing kinetic analysis - simplex optimization - molybdenum Supported by the National Natural Science Foundation of China (Grant No. 20175013) and the Higher Education Development Foundation of Shanghai in China (Grant No. 01A17)展开更多
This paper presents a new method called improved oscillographic chronopotcntiometry. It changes the incision of dE/dt-E curve into a peak shape and has the advantages of good reproducibility and wider linear range.
Applying Fourier transform technique to deduction of background and noise on dE/dt-t curve, a new electrochemical method, high order harmonic oscillographic chronopotentiometry is proposed in this paper.
By applying the convolution technique to the treatment of oscillographic signal, a new electroanalytical method, 0.5-3.5 order differential A.C. oscillographic chronopotentiometry is presented. This note represents th...By applying the convolution technique to the treatment of oscillographic signal, a new electroanalytical method, 0.5-3.5 order differential A.C. oscillographic chronopotentiometry is presented. This note represents the experimental circuits, principle and characteristics of the method.展开更多
Using a wavelet function as the filter function of Fourier self-deconvolution, a new method of resolving overlapped peaks, wavelet-Fourier self-deconvolution, is founded. The properties of different wavelet deconvolut...Using a wavelet function as the filter function of Fourier self-deconvolution, a new method of resolving overlapped peaks, wavelet-Fourier self-deconvolution, is founded. The properties of different wavelet deconvolution functions are studied. In addition, a cutoff value coefficient method of eliminating artificial peaks and wavelet method of removing shoulder peaks using the ratio of maximum peak to minimum peak is established. As a result, some problems in classical Fourier self-deconvolution are solved, such as the bad result of denoising, complicated processing, as well as usual appearance of artificial and shoulder peaks. Wavelet-Fourier self-deconvolution is applied to determination of multi-components in oscillographic chronopotentiometry. Experimental results show that the method has characteristics of simpler process and better effect of processing.展开更多
The investigation on oscillographic chronopotentiometry after 2000 is reviewed. The development course of oscillographic chronopotentiometry is looked back. Some new instrumentations and new methods about oscillograph...The investigation on oscillographic chronopotentiometry after 2000 is reviewed. The development course of oscillographic chronopotentiometry is looked back. Some new instrumentations and new methods about oscillographic chronopotentiometry as well as applications of chemometrics in oscilloanalysis are introduced. The prospects of oscillographic chronopotentiometry development are also discussed in this paper.展开更多
基金the National Natural Science Foundation of China(Nos.52001310 and 52130002)the National Science and Technology Major Project(No.J2019-VI-0019-0134)+1 种基金KC Wong Education Foundation(No.GJTD-2020-09)Institute of Metal Res earch Innovation Fund(No.2023-ZD01)。
文摘Compared with the conventional Charpy impact test method,the oscillographic impact test can help in the behavioral analysis of materials during the fracture process.In this study,the trade-off relationship between the strength and toughness of a DZ2 axle steel at various tempering temperatures and the cause of the improvement in impact toughness was evaluated.The tempering process dramatically influenced carbide precipitation behavior,which resulted in different aspect ratios of carbides.Impact toughness improved along with the rise in tempering temperature mainly due to the increase in energy required in impact crack propagation.The characteristics of the impact crack propagation process were studied through a comprehensive analysis of stress distribution,oscilloscopic impact statistics,fracture morphology,and carbide morphology.The poor impact toughness of low-tempering-temperature specimens was attributed to the increased number of stress concentration points caused by carbide morphology in the small plastic zone during the propagation process,which resulted in a mixed distribution of brittle and ductile fractures on the fracture surface.
基金The authors gratefully acknowedge the financial support from the National Natural Scicllcc Foundation of China Nat
文摘A novel electroanalytical method. oscillographic chronopotentiometry with high and low frequency current. is presented in this paper. With this method, the sensitivity or almost all kinds of oscillographic chronopotentiometry can be: enhanced about one order.
文摘A high speed data sampling system on dynamic Oscillographic analysis was established with a 80386DX40 computer, AD 674 and flow injection system. Programs were designed in Microsoft Windows 3.1, that can process E-t, dE/dt-t, i'(f)-t and other kinds of curve on oscillographic analysis. A satisfactory result on determination of Pb2+ and Cd2+ was obtained.
文摘A new method of oscillographic chronopotentiometry at silver disk electrode was investigated. By using it, a series of ions such as Pb, In, Cr, Tl, Bi etc. were determined. The detection limits are two or three orders of magnitude lower than those by oscillographic chronopotentiometry at mercury electrode. The proposed method is characterized by fine sensitivity, stable oscillogram and no mercury. The research on the mechanism of this method shows that these achievements are caused by the characterristics of silver electroxidation and electroreduction and the oscillographic chronopotentiometry (OC).
文摘A new method called differential reciprocal oscillographic chronopotentiometric titration is presented.It makes use of appearance or disappearance of a peak of depolarizer on differential reciprocal oscillogram indicating the end point of titration.This method was applied to titration of Pb^(2+),Cd^(2+),Ni^(2+),Co^(3+),Zn^(2+),Ga^(3+) and Cu^(2+)by EDTA or EGTA.The end point of titration is very easy to observe and the sensibility of the method is higher than that of diffcrcntial oscillographic chronopotcntiometric titration.
基金The project was supported by the National Natural Science Foundation of China(No.20275030)the Natural Science Foundation of Shaanxi Province in China(No.2004B20).
文摘A small oscillogram, one end of which was substituted by a bright point caused by the redox of an appropriate depolarizer and the other end of which was the redox of Hg or the redox of supporting electrolyte cation, was investigated in this paper. Experimental results of application of the small oscillogram to oscillographic determination of cefoperazone showed that the small osciUogram was more stable, sensitive, and less interference than classical oscillogram.
文摘Reciprocal oscillographic chronopotentiogram is such a curve that can converts incisions on "(dE/dt)-E" oscillogram into peaks on "(dt/dE)-E" curve. In order to increase the sensitivity, a new technique called feeding back current was added in new circuit of obtaining reciprocal oscillgraphic chronopotentiogram. It can make capacity current be subtracted easily. Using this method, we carry out studying on principle and titration of drug.
文摘Under the optimum experimental conditions (i. e., pH=1.6, c KI=10.6 mmol/L, =5.4 mmol/L, =1.30 mmol/L) derived from simplex operations, trace molybdenum(VI) was determined through the agency of its catalytic effect on the reaction of H2O2 with I? in acid medium. The detection limit and linear calibration range of molybdenum were obtained as 0.5×10?6 mol/L and 0.5×10?6～120×10?6mol/L respectively. This method was applied to the examination of the industrial waste water, and the recovery ratios were found to be in the range of 101% and 107%. Key words oscillographic potentiometry - catalyzing kinetic analysis - simplex optimization - molybdenum Supported by the National Natural Science Foundation of China (Grant No. 20175013) and the Higher Education Development Foundation of Shanghai in China (Grant No. 01A17)
文摘This paper presents a new method called improved oscillographic chronopotcntiometry. It changes the incision of dE/dt-E curve into a peak shape and has the advantages of good reproducibility and wider linear range.
文摘Applying Fourier transform technique to deduction of background and noise on dE/dt-t curve, a new electrochemical method, high order harmonic oscillographic chronopotentiometry is proposed in this paper.
文摘By applying the convolution technique to the treatment of oscillographic signal, a new electroanalytical method, 0.5-3.5 order differential A.C. oscillographic chronopotentiometry is presented. This note represents the experimental circuits, principle and characteristics of the method.
文摘Using a wavelet function as the filter function of Fourier self-deconvolution, a new method of resolving overlapped peaks, wavelet-Fourier self-deconvolution, is founded. The properties of different wavelet deconvolution functions are studied. In addition, a cutoff value coefficient method of eliminating artificial peaks and wavelet method of removing shoulder peaks using the ratio of maximum peak to minimum peak is established. As a result, some problems in classical Fourier self-deconvolution are solved, such as the bad result of denoising, complicated processing, as well as usual appearance of artificial and shoulder peaks. Wavelet-Fourier self-deconvolution is applied to determination of multi-components in oscillographic chronopotentiometry. Experimental results show that the method has characteristics of simpler process and better effect of processing.
基金supported by the National Natural Science Foundation of China(Grant No.20275030)the Natural Science Foundation of Shaanxi Province in China(No.2004B20).
文摘The investigation on oscillographic chronopotentiometry after 2000 is reviewed. The development course of oscillographic chronopotentiometry is looked back. Some new instrumentations and new methods about oscillographic chronopotentiometry as well as applications of chemometrics in oscilloanalysis are introduced. The prospects of oscillographic chronopotentiometry development are also discussed in this paper.
