The aging properties of Cu-0.35Cr-0.038Zr-0.055Ce alloy are studied. The results show that can obtain higher electrical conductivity and microhardness after solutioned at 920°Cfor Ih, and aged at 500°C. The ...The aging properties of Cu-0.35Cr-0.038Zr-0.055Ce alloy are studied. The results show that can obtain higher electrical conductivity and microhardness after solutioned at 920°Cfor Ih, and aged at 500°C. The process of precipitation of the secondary phase can be accelerated with cold deformation before aging, so properties of the alloy are improved. Upon aging at 500°C for 30 minutes after 60% cold deformation, the values of electrical conductivity and microhardness are 69.0%IACS and 152HV respectively, but they are only 66.2%IACS and 136HV upon directly aging after solution. With the addition of a trace of rare earth element Ce, the value of microhardness of Cu-0.35Cr-0.038Zr alloy increases 18-25HV, while the value of electrical conductivity drops a little.展开更多
The microstructure of surface peeling in finish rolled Cu-0.1Fe-0.03P sheetis analyzed by scanning electron microscope and energy dispersive spectroscope. Fe-rich areas ofdifferent contents are observed in the matrix....The microstructure of surface peeling in finish rolled Cu-0.1Fe-0.03P sheetis analyzed by scanning electron microscope and energy dispersive spectroscope. Fe-rich areas ofdifferent contents are observed in the matrix. The stress distributions and strain characteristicsat the interface between Cu matrix and Fe particle are studied by elastic-plastic finite elementplane strain model. Larger Fe particles and higher deforming extent of finish rolling are attributedto the intense stress gradient and significant non-homogeneity equivalent strain at the interfaceand accelerate surface peeling of Cu-0.1Fe-0.03P lead frame sheet.展开更多
This paper presents the effects of aging processes on the properties and microstructure of Cu-0.3Cr-0.15Zr-0.05Mg lead frame alloy. Optimal conditions for good hardening and electrical conductivity can be obtained by ...This paper presents the effects of aging processes on the properties and microstructure of Cu-0.3Cr-0.15Zr-0.05Mg lead frame alloy. Optimal conditions for good hardening and electrical conductivity can be obtained by solution treating at 920 °C for Ih and aging at 470^0 for 4h and at 550^ for Ih. The hardness and electrical conductivity can reach 108HV, 73%IACS and 106HV, 76%IACS, respectively. Aging precipitation was dealt with by transmission electronic microscope (TEM). At 470 °C aging for 4h the fine precipitation of an ordered compound CrCu2(Zr,Mg) is found in matrix as well as fine Cr and Cu4Zr. Aging at 550’C for Ih some precipitates are still coherent with matrix. The CrCu2(Zr,Mg) completely dissolves into Cr and Cu4Zr.展开更多
The non-linear relationship between parameters of rapidly solidified agingprocesses and mechancal and electrical properties of Cu-Cr-Zr alloy is available by using asupervised artificial neural network (ANN). A knowle...The non-linear relationship between parameters of rapidly solidified agingprocesses and mechancal and electrical properties of Cu-Cr-Zr alloy is available by using asupervised artificial neural network (ANN). A knowledge repository of rapidly solidified agingprocesses is established via sufficient data learning by the network. The predicted values of theneural network are in accordance with the tested data. So an effective measure for foreseeing andcontrolling the properties of the processing is provided.展开更多
Precipitation behavior of the early aging stage and the transformation kinetics were studied by analysing the electrical resistance variation of the solution Cu-Ni-Si alloy in the process of aging. Due to the linear r...Precipitation behavior of the early aging stage and the transformation kinetics were studied by analysing the electrical resistance variation of the solution Cu-Ni-Si alloy in the process of aging. Due to the linear relationship between electrical conductivity and volume fraction of precipitates, the transformation kinetics equation can be educed from the Avrami empirical formula, on the basis of this equation, transformation kinetics curve and "C" curve of the isothermal transformation were established.展开更多
PSN-PZN-PZT + x wt. %Cr2O3, X = 0.0-0-9, were prepared by conventional mixed oxide techniques at sintering temperatures of 1220 degrees C-1300 degrees C for 2 h. The effect of sintering temperature on the microstructu...PSN-PZN-PZT + x wt. %Cr2O3, X = 0.0-0-9, were prepared by conventional mixed oxide techniques at sintering temperatures of 1220 degrees C-1300 degrees C for 2 h. The effect of sintering temperature on the microstructure and the piezoelectric properties was investigated by XRD, SEM, and other conventional measurement. The result indicated that with temperature increasing, the valence of Cr ion from Cr5+ or Cr6+ changes into C3+, and the piezoelectric properties turn hard. With increasing Cr2O3 content, the amount of rhombohedral phases increases and the morphotropic boundary phase is correspondingly shifts to rhombohedral phase. A uniform microstructure and excellent comprehensive properties were obtained at 1240 degrees C as the amount of Cr2O3 is 0.5 wt.%.展开更多
Rapid solidifiation is a kind of new process for enhancing the hardness and electrical conductivity of Cu-Cr-Zr copper alloy.The use of BP neural network(NN) is presented to model the non-linear relationship between p...Rapid solidifiation is a kind of new process for enhancing the hardness and electrical conductivity of Cu-Cr-Zr copper alloy.The use of BP neural network(NN) is presented to model the non-linear relationship between parameters of age hardening processes and the mechanical and electrical properties of rapdily solidified Cu-Cr-Zr alloy.The improved model is developed by the Levenberg-Marquardt training algorithm and the good generalization performance is demonstrated.So,an important foundation has been laid for optimisticaly controlling the rapidly solidified aging processes of Cu-Cr-Zr alloy.展开更多
The interaction between precipitation and recrystallization and its effect on the properties of the re-aged Cu-Ni-Si alloy are discussed. The results indicate that the pre-aging process for Cu-Ni-Si alloy was responsi...The interaction between precipitation and recrystallization and its effect on the properties of the re-aged Cu-Ni-Si alloy are discussed. The results indicate that the pre-aging process for Cu-Ni-Si alloy was responsible to the significant strengthening effect in re-aging process, and the re-aging strengthening effect with pre-aging at 450°C for 8h was even more remarkable. Upon aging, a phenomenon of simultaneous in situ and discontinuous recrystallization was observed in the treatment of pre-aging and deformed Cu-Ni-Si alloy. On the formation and growth of recrystallization, the precipitated phases are coarsed or dissolved in the front of grain boundaries following a re-precipitation in the recrystallization area.展开更多
Kai Xin San (KXS) is a category of traditional complex prescription that wasfirst recorded in Bei Ji Qian Jin Yao Fang by SUN Si-miao in the Tang Dynasty and then also recordedin Tai Ping Hui Min He Ji Ju Fang, Qian J...Kai Xin San (KXS) is a category of traditional complex prescription that wasfirst recorded in Bei Ji Qian Jin Yao Fang by SUN Si-miao in the Tang Dynasty and then also recordedin Tai Ping Hui Min He Ji Ju Fang, Qian Jin Yao Fang and Gu Jin Lu Yan in later generations. It wasmainly used by herbalist doctors to treat symptoms including desolation, moodiness, forgetfulnessetc. , which are similar to the neurosis such as depression, anxiety and difficulty in studying andmemory in the West medicine. The former recorded formulas were all composed of ginseng, polygala,hoelen and acori graminei with different proportion. But there are no systematic studies on theclinical adaptive symptom corresponding to different matching and the best anti-depressive matchingso far. In this study, the classical anti-depressive animal model, namely, ' force swimming model'and 'suspend tail model' were adopted to appraise the anti-depressive effect of the aforementionedformulas and the pharmacodynamical distinction between the whole formula decoction and the activecombination made up with each effective component from ginseng, polygala, hoelen and acori graminewere also investigated, which would provide scientific evidence for properly using KXS in clinic.展开更多
Hematopoiesis is an active process of cell proliferation, differentiation andrelease. It is the process during which hematopoietic stem cells (HSCs) proliferate anddifferentiate to mature blood cells under the effect ...Hematopoiesis is an active process of cell proliferation, differentiation andrelease. It is the process during which hematopoietic stem cells (HSCs) proliferate anddifferentiate to mature blood cells under the effect of hemetopoietic growth factors (HGFs) incertain hematopoietic microenvironment. HSCs are sources of hematopoiesis of a body that canself-renew, differentiate to blood cells of every lineage and maintain the constancy of them. As themajor tissue of hematopoiesis bone marrow is filled with all kinds of blood cells in variousdevelopmental stages. Under the normal conditions, the ordered proliferation and differentiation ofhematopoietic stem cells/hematopoietic progenitor cells ( HSC/HPC) depend on the regulation ofcytokine network. In present, Spatholobus suberectus Dunn (SSD), a traditional Chinese herb medicinethat has been used to invigorate the blood circulation for thousands years, is widely used torebuild blood after chemotherapy and radiotherapy and to treat hematopoietic diseases. Previousreports from our laboratory indicated that (2S,3R)-ent-catechin, epi (2S, 3R )-ent-catechin, gallic( 2S, 3R )-ent-catechin, et al extracted from SSD all could stimulate the proliferation of HPC inmarrow depressed mice, among which (2S, 3R)-ent-catechin obtained from spatholobus genus for thefirst time and whose content was the maxim showed the best effect. In this study, firstly, theeffect of (2S,3R)-ent-catechin on the quality and quantity of HSCs were assayed by detectingCD_(34)^+ expression. Secondly, we investigated the variation of cytokine (GM-CSF and IL-6)sero-level in mice treated with (2S,3R)- ent-catechin by ELISA. And IL-6 mRNA and GM-CSF mRNAexpressions induced by (2S,3R)-ent-catechin were detected simultaneously by RT-PCR technique inorder to clarify its mechanism.展开更多
基金supported by the National 863 Plan Items of China(No.2002AA331112)
文摘The aging properties of Cu-0.35Cr-0.038Zr-0.055Ce alloy are studied. The results show that can obtain higher electrical conductivity and microhardness after solutioned at 920°Cfor Ih, and aged at 500°C. The process of precipitation of the secondary phase can be accelerated with cold deformation before aging, so properties of the alloy are improved. Upon aging at 500°C for 30 minutes after 60% cold deformation, the values of electrical conductivity and microhardness are 69.0%IACS and 152HV respectively, but they are only 66.2%IACS and 136HV upon directly aging after solution. With the addition of a trace of rare earth element Ce, the value of microhardness of Cu-0.35Cr-0.038Zr alloy increases 18-25HV, while the value of electrical conductivity drops a little.
基金This project is supported by 863 Program of China (N0.2002AA331112)Doctoral Foundation of Northwestern Polytechnical University.
文摘The microstructure of surface peeling in finish rolled Cu-0.1Fe-0.03P sheetis analyzed by scanning electron microscope and energy dispersive spectroscope. Fe-rich areas ofdifferent contents are observed in the matrix. The stress distributions and strain characteristicsat the interface between Cu matrix and Fe particle are studied by elastic-plastic finite elementplane strain model. Larger Fe particles and higher deforming extent of finish rolling are attributedto the intense stress gradient and significant non-homogeneity equivalent strain at the interfaceand accelerate surface peeling of Cu-0.1Fe-0.03P lead frame sheet.
文摘This paper presents the effects of aging processes on the properties and microstructure of Cu-0.3Cr-0.15Zr-0.05Mg lead frame alloy. Optimal conditions for good hardening and electrical conductivity can be obtained by solution treating at 920 °C for Ih and aging at 470^0 for 4h and at 550^ for Ih. The hardness and electrical conductivity can reach 108HV, 73%IACS and 106HV, 76%IACS, respectively. Aging precipitation was dealt with by transmission electronic microscope (TEM). At 470 °C aging for 4h the fine precipitation of an ordered compound CrCu2(Zr,Mg) is found in matrix as well as fine Cr and Cu4Zr. Aging at 550’C for Ih some precipitates are still coherent with matrix. The CrCu2(Zr,Mg) completely dissolves into Cr and Cu4Zr.
基金This project is financially suported by the State"863 Plan"(No.2002AA331112)
文摘The non-linear relationship between parameters of rapidly solidified agingprocesses and mechancal and electrical properties of Cu-Cr-Zr alloy is available by using asupervised artificial neural network (ANN). A knowledge repository of rapidly solidified agingprocesses is established via sufficient data learning by the network. The predicted values of theneural network are in accordance with the tested data. So an effective measure for foreseeing andcontrolling the properties of the processing is provided.
基金supported by the National High Technology Research Project“863”under Grant No.2002AA331112the Major Science and Technology Project of Henan Province,China,under Grant No.0122021300.
文摘Precipitation behavior of the early aging stage and the transformation kinetics were studied by analysing the electrical resistance variation of the solution Cu-Ni-Si alloy in the process of aging. Due to the linear relationship between electrical conductivity and volume fraction of precipitates, the transformation kinetics equation can be educed from the Avrami empirical formula, on the basis of this equation, transformation kinetics curve and "C" curve of the isothermal transformation were established.
文摘PSN-PZN-PZT + x wt. %Cr2O3, X = 0.0-0-9, were prepared by conventional mixed oxide techniques at sintering temperatures of 1220 degrees C-1300 degrees C for 2 h. The effect of sintering temperature on the microstructure and the piezoelectric properties was investigated by XRD, SEM, and other conventional measurement. The result indicated that with temperature increasing, the valence of Cr ion from Cr5+ or Cr6+ changes into C3+, and the piezoelectric properties turn hard. With increasing Cr2O3 content, the amount of rhombohedral phases increases and the morphotropic boundary phase is correspondingly shifts to rhombohedral phase. A uniform microstructure and excellent comprehensive properties were obtained at 1240 degrees C as the amount of Cr2O3 is 0.5 wt.%.
文摘Rapid solidifiation is a kind of new process for enhancing the hardness and electrical conductivity of Cu-Cr-Zr copper alloy.The use of BP neural network(NN) is presented to model the non-linear relationship between parameters of age hardening processes and the mechanical and electrical properties of rapdily solidified Cu-Cr-Zr alloy.The improved model is developed by the Levenberg-Marquardt training algorithm and the good generalization performance is demonstrated.So,an important foundation has been laid for optimisticaly controlling the rapidly solidified aging processes of Cu-Cr-Zr alloy.
基金supported by the National High Technology Research Project“863”under Grant No.2002AA331112the Major Science and Technology Project of Henan Province,China,under Grant No.012202l300.
文摘The interaction between precipitation and recrystallization and its effect on the properties of the re-aged Cu-Ni-Si alloy are discussed. The results indicate that the pre-aging process for Cu-Ni-Si alloy was responsible to the significant strengthening effect in re-aging process, and the re-aging strengthening effect with pre-aging at 450°C for 8h was even more remarkable. Upon aging, a phenomenon of simultaneous in situ and discontinuous recrystallization was observed in the treatment of pre-aging and deformed Cu-Ni-Si alloy. On the formation and growth of recrystallization, the precipitated phases are coarsed or dissolved in the front of grain boundaries following a re-precipitation in the recrystallization area.
文摘Kai Xin San (KXS) is a category of traditional complex prescription that wasfirst recorded in Bei Ji Qian Jin Yao Fang by SUN Si-miao in the Tang Dynasty and then also recordedin Tai Ping Hui Min He Ji Ju Fang, Qian Jin Yao Fang and Gu Jin Lu Yan in later generations. It wasmainly used by herbalist doctors to treat symptoms including desolation, moodiness, forgetfulnessetc. , which are similar to the neurosis such as depression, anxiety and difficulty in studying andmemory in the West medicine. The former recorded formulas were all composed of ginseng, polygala,hoelen and acori graminei with different proportion. But there are no systematic studies on theclinical adaptive symptom corresponding to different matching and the best anti-depressive matchingso far. In this study, the classical anti-depressive animal model, namely, ' force swimming model'and 'suspend tail model' were adopted to appraise the anti-depressive effect of the aforementionedformulas and the pharmacodynamical distinction between the whole formula decoction and the activecombination made up with each effective component from ginseng, polygala, hoelen and acori graminewere also investigated, which would provide scientific evidence for properly using KXS in clinic.
文摘Hematopoiesis is an active process of cell proliferation, differentiation andrelease. It is the process during which hematopoietic stem cells (HSCs) proliferate anddifferentiate to mature blood cells under the effect of hemetopoietic growth factors (HGFs) incertain hematopoietic microenvironment. HSCs are sources of hematopoiesis of a body that canself-renew, differentiate to blood cells of every lineage and maintain the constancy of them. As themajor tissue of hematopoiesis bone marrow is filled with all kinds of blood cells in variousdevelopmental stages. Under the normal conditions, the ordered proliferation and differentiation ofhematopoietic stem cells/hematopoietic progenitor cells ( HSC/HPC) depend on the regulation ofcytokine network. In present, Spatholobus suberectus Dunn (SSD), a traditional Chinese herb medicinethat has been used to invigorate the blood circulation for thousands years, is widely used torebuild blood after chemotherapy and radiotherapy and to treat hematopoietic diseases. Previousreports from our laboratory indicated that (2S,3R)-ent-catechin, epi (2S, 3R )-ent-catechin, gallic( 2S, 3R )-ent-catechin, et al extracted from SSD all could stimulate the proliferation of HPC inmarrow depressed mice, among which (2S, 3R)-ent-catechin obtained from spatholobus genus for thefirst time and whose content was the maxim showed the best effect. In this study, firstly, theeffect of (2S,3R)-ent-catechin on the quality and quantity of HSCs were assayed by detectingCD_(34)^+ expression. Secondly, we investigated the variation of cytokine (GM-CSF and IL-6)sero-level in mice treated with (2S,3R)- ent-catechin by ELISA. And IL-6 mRNA and GM-CSF mRNAexpressions induced by (2S,3R)-ent-catechin were detected simultaneously by RT-PCR technique inorder to clarify its mechanism.
