Tension-compression fatigue test was performed on 0.45% C steel specimens.Normal and tangential components of magnetic memory testing signals,Hp(y) and Hp(x) signals,with their characteristics,K of Hp(y) and Hp(x)M of...Tension-compression fatigue test was performed on 0.45% C steel specimens.Normal and tangential components of magnetic memory testing signals,Hp(y) and Hp(x) signals,with their characteristics,K of Hp(y) and Hp(x)M of Hp(x),throughout the fatigue process were presented and analyzed.Abnormal peaks of Hp(y) and peak of Hp(x) reversed after loading; Hp(y) curves rotated clockwise and Hp(x) curves elevated significantly with the increase of fatigue cycle number at the first a few fatigue cycles,both Hp(y) and Hp(x) curves were stable after that,the amplitude of abnormal peaks of Hp(y) and peak value of Hp(x) increased more quickly after fatigue crack initiation.Abnormal peaks of Hp(y) and peak of Hp(x) at the notch reversed again after failure.The characteristics were found to exhibit consistent tendency in the whole fatigue life and behave differently in different stages of fatigue.In initial and crack developing stages,the characteristics increased significantly due to dislocations increase and crack propagation,respectively.In stable stage,the characteristics remained constant as a result of dislocation blocking,K value ranged from 20 to 30 A/(m·mm)-1,and Hp(x)M ranged from 270 to 300 A/m under the test parameters in this work.After failure,both abnormal peaks of Hp(y) and peak of Hp(x) reversed,K value was 133 A/(m·mm)-1 and Hp(x)M was-640 A/m.The results indicate that the characteristics of Hp(y) and Hp(x) signals were related to the accumulation of fatigue,so it is feasible and applicable to monitor fatigue damage of ferromagnetic components using metal magnetic memory testing(MMMT).展开更多
The research goal is to develop a new solar water heater system(SWHS) that uses a solar bubble pump instead of an electric pump.The pump is powered by the steam produced from an evacuated tube collector.Therefore,heat...The research goal is to develop a new solar water heater system(SWHS) that uses a solar bubble pump instead of an electric pump.The pump is powered by the steam produced from an evacuated tube collector.Therefore,heat could be transferred downward from the collector to a hot water storage tank.The designed system consists of two sets of heat-pipe evacuated tube collectors,a solar bubble pump installed at an upper level and a water storage tank with a heat exchanger at a lower level.Discharge heads of 1 and 5 m were tested.The bubble pump could operate at the collector temperature of about 90-100 ℃ and vapor gage pressure of 80-90 kPa.It is found that water circulation within the SWHS depends on the incident solar intensity and system discharge head.Experimental investigations are conducted to obtain the system thermal efficiencies from the hourly,daily and long-term performance tests.The thermal performance of the proposed system is compared with conventional solar water heaters.The results show that the proposed system achieves system characteristic efficiency of 10% higher than that of the conventional systems using electric pump if taking the consumption of electric power into account.And the former is a zero carbon system.展开更多
Objective： HPP （Hypophosphatasia） is a congenital disease characterized by a deficiency of tissue-specific ALP （alkaline phosphatase）, which causes the generation of abnormal bone and tooth tissue. The clinical m...Objective： HPP （Hypophosphatasia） is a congenital disease characterized by a deficiency of tissue-specific ALP （alkaline phosphatase）, which causes the generation of abnormal bone and tooth tissue. The clinical manifestations are variable, from neonatal forms with high mortality to milder adult forms with fractures and osteomalacia. The present study reports a clinical case of HPP, with emphasis on the physical characteristics and laboratory tests. The patient was attended at the medical genetics outpatient clinic of the Association of Parents and Friends of the Exceptional of Manaus （Associa？？o de Pais e Amigos dos Excepcionais-APAE/Manaus）. Methodology： For the case report, anamnesis, peripheral blood G-band karyotyping, Vitamin and ALP dosage and resonance examination were performed. Results： A.M.M.S, 9 years, non-consanguineous parents, no bone disease in the family, with one sister from the mother. Birth weight AGA without intercurrence. The patient presented a slight delay in psycho-motor development and was diagnosed with craniostenosis through CNS imaging examination. The physical examination, in addition to a short stature, showed dolichocephaly, frontal bossing, curved tibias and great dental compromise with many early cavities and loss of teeth. Laboratory evaluation： ALP dosage： 63/L （N = 69-325）; Vitamin B6 dosage： 27.4 （5.2-34.1）. The mother and the younger sister also had an ALP result below that expected for the age. Conclusions： The clinical phenotype and laboratory diagnosis of the patient were compatible with ICD Q78 HPP.展开更多
The spatial variability of geotechnical earthquake engineering critical parameters obtained by laboratory and in situ tests in the same area is affected by different measurements. The paper provides a brief synthesis ...The spatial variability of geotechnical earthquake engineering critical parameters obtained by laboratory and in situ tests in the same area is affected by different measurements. The paper provides a brief synthesis of ground motion and site effects analysis procedures within a Performance-Based Design framework. In particular it focuses about the influence on the evaluation of site effects in some active regions by different shear waves velocity measurements （Down Hole D-H and Seismic Dilatometer Marchetti Test SDMT）. Moreover the variation of shear modulus and damping ratio with strain level and depth from different laboratory dynamic or cyclic tests for soil characterisation （Resonant Column Test RCT） was evaluated. The available data enabled one to compare the shear waves velocity profile obtained by laboratory and in situ tests （Cone Penetration Tests CPT） with empirical correlations proposed in literature.展开更多
This study is aimed at the thermal analysis of sealant mortar （usually a mixtures of bentonite and cemem with addition of sand） used in geothermal cooling and heating. In particular, thermal conductivity and diffusi...This study is aimed at the thermal analysis of sealant mortar （usually a mixtures of bentonite and cemem with addition of sand） used in geothermal cooling and heating. In particular, thermal conductivity and diffusivity measurements were performed on differem sealant mixtures by using Hot Disk thermal constants analyzer in order to identify the interesting thermal properties of grouting materials. The grouting materials that we considered are of porous nature and, if used in the presence of groundwater, have different levels of imbibitions. It is important to know the thermal behavior of these materials at different water content. A first set of measurements was performed on a not-tinted material at room temperature; then the samples were led to saturation conditions by contact capillary imbibitions with a cotton wool layer moistened in water. The determination of thermal conductivity in these test conditions appears to be critical compared to the measuremems on non-timed sample. The thermal conductivity tests have revealed how the thermal behavior of the samples analyzed is essentially determined by the density and water content of the material： in fact, the thermal conductivity increases of two to three times the value of the not-tinted material.展开更多
Measurement of the volume of gas adsorbed per unit mass of coal with increasing pressure at a constant temperature produces an isotherm that describes the gas storage capacity of this type of coal. The accurate testin...Measurement of the volume of gas adsorbed per unit mass of coal with increasing pressure at a constant temperature produces an isotherm that describes the gas storage capacity of this type of coal. The accurate testing and interpretation of coal sorption isotherm plays an important role in the areas of coal mine methane drainage, coalbed methane （CBM） reservoir resource assessment, enhanced coalbed methane （ECBM） recovery, as well as the carbon dioxide （CO2） sequestration in deep coal seams or similar geological formations. Different coal sorption isotherm testing apparatus and associated calculation methods are critically reviewed and presented in this paper. These include both volumetric and gravimetric based methods, as well as experimental sorption tests with confining stress and direction sorption methods. The volumetric techniques utilise experimental apparatus with sample cell and injection pump and that with both sample cell and reference cell. Whilst the gravimetric approachesinclude methods with sample cell and suspension magnetic balance and that with both sample cell and reference cell. Different testing methods are compared and discussed in this study. A unique in-house-built coal sorption isotherm testing apparatus at the University of Wollongong was presented together with the calculation method, procedures and experimental results. The isotherm results can be calculated by both Soave-Redlich-Kwong （SRK） equation and calibration cure methods which can be used directly to convert the volume of adsorbed gas in different test conditions to standard condition （NTP）.展开更多
An experimental analysis is performed to evaluate Rogowski coil performance for PD （partial discharge） location on overhead CC （covered-conductor） distribution lines. The measuring set-up is arranged in high volta...An experimental analysis is performed to evaluate Rogowski coil performance for PD （partial discharge） location on overhead CC （covered-conductor） distribution lines. The measuring set-up is arranged in high voltage laboratory. A multi-end measuring method is chosen as a technique to locate PD source point on the line. A power transformer is used to energize one end of the CC line by the AC voltage source. The performance of Rogowski-coil is tested in noisy environment. The tests are carried out conceming different measurement conditions such as off-line and on-line PD measuring systems. The results obtained from the laboratory measurements confirm the capability of the Rogowski-coil in order to measure and locate the high frequency PD source on the CC line in consistent with energizing AC source. Chirp detector is used as a signal-processing tool in order to extract the PD signals and then apply the locator algorithm.展开更多
Information on seed vigor of the vegetable crops is always important and necessary due to the increasing demand of high quality seeds for sowing and high-value commercial. The cultivation of these species, conducted i...Information on seed vigor of the vegetable crops is always important and necessary due to the increasing demand of high quality seeds for sowing and high-value commercial. The cultivation of these species, conducted intensively, should be established with seed high potential physiological and health for the development of a more productive and sustainable agriculture. The present study was conducted to evaluate the potential physiological of seed lots of radish and coriander. The experiment was conducted at the laboratory of seed analysis and greenhouse of the plant science department of the Federal University of Pelotas in South Brazil. Four radish seed lots, cultivar ＂Saxa＂, and four coriander seed lots, cultivar ＂Verdito＂ were used. Germination seed test, first count of germination, accelerated aging test, electrical conductivity and seedling emergence were used to evaluate the physiological quality of the lots. The experimental design was completely randomized design with five replications. Means were compared by Tukey test. The accelerated aging test was the most efficient test in assessing the physiological quality for both lots of radish seeds and coriander and this test provide coherent results with seedlings emergence.展开更多
Objective:To observe the effects of muscle regions of meridians needling method combined with auricular point sticking on pain and lumbar range of motion in patients with chronic nonspecific low back pain.Methods:A to...Objective:To observe the effects of muscle regions of meridians needling method combined with auricular point sticking on pain and lumbar range of motion in patients with chronic nonspecific low back pain.Methods:A total of 100 patients with chronic nonspecific low back pain were randomly divided into a control group and an observation group,with 50 patients in each group.Both groups received auricular point sticking treatment,while the control group received additional conventional acupuncture treatment,and the observation group received additional muscle regions of meridians needling method.The total effective rate of the two groups was compared after 4 weeks of treatment.Before treatment and after 1 week and 4 weeks of treatment,the visual analog scale(VAS)score was used to assess the degree of low back pain,and the modified-modified Schober(MMS)score was used to evaluate the lumbar range of motion.Results:There was statistical significance in comparing the total effective rate between the two groups(P<0.01).During the treatment process,as the number of treatments increased,the VAS score gradually decreased,and the MMS score gradually increased in both groups.After 1 week and 4 weeks of treatment,the VAS score in the observation group was lower than that in the control group(P<0.01),and the MMS score in the observation group was higher than that in the control group(P<0.01).During the treatment period,no serious adverse reactions occurred in either group.Conclusion:Based on auricular point sticking treatment,muscle regions of meridians needling method is more effective than conventional acupuncture in treating chronic nonspecific low back pain since it is able to significantly reduce the pain and improve the lumbar range of motion.展开更多
In this paper a critical review is presented of the history and current state of the art of J-integral resistance curve testing and experimental evaluation methods in conjunction with a discussion of the development o...In this paper a critical review is presented of the history and current state of the art of J-integral resistance curve testing and experimental evaluation methods in conjunction with a discussion of the development of the plane strain fracture toughness test standard ASTM E1820 developed by American Society for Testing and Materials (ASTM). Early research efforts on this topic are reviewed first. These include the J-integral concept, experimental estimates of the J-integral for stationary cracks, load line displacement (LLD) and crack mouth opening displacement (CMOD) based η factor equations, different formulations of J-integral incremental equations for growing cracks, crack growth corrected J-R curve determination, and experimental test methods. Recent developments in J-R curve testing and evaluation are then described, with emphasis on accurate J-integral incremental equations, a normalization method, a modified basic method, a CMOD direct method with use of incremental equations, relationships of plastic geometry factors, constraint-dependent J-R curve testing and correction approaches. An overview of the present fracture toughness test standard ASTM E1820-08a is then presented. The review shows that after more than 40 years of investigation and development, the J-integral resistance curve test methods in ASTM E1820 have become simpler, more cost-effective and more accurate.展开更多
基金Projects(50975283,50975287)supported by the National Natural Science Foundation of ChinaProject(2011CB013401)supported by the National Basic Research Program,China
文摘Tension-compression fatigue test was performed on 0.45% C steel specimens.Normal and tangential components of magnetic memory testing signals,Hp(y) and Hp(x) signals,with their characteristics,K of Hp(y) and Hp(x)M of Hp(x),throughout the fatigue process were presented and analyzed.Abnormal peaks of Hp(y) and peak of Hp(x) reversed after loading; Hp(y) curves rotated clockwise and Hp(x) curves elevated significantly with the increase of fatigue cycle number at the first a few fatigue cycles,both Hp(y) and Hp(x) curves were stable after that,the amplitude of abnormal peaks of Hp(y) and peak value of Hp(x) increased more quickly after fatigue crack initiation.Abnormal peaks of Hp(y) and peak of Hp(x) at the notch reversed again after failure.The characteristics were found to exhibit consistent tendency in the whole fatigue life and behave differently in different stages of fatigue.In initial and crack developing stages,the characteristics increased significantly due to dislocations increase and crack propagation,respectively.In stable stage,the characteristics remained constant as a result of dislocation blocking,K value ranged from 20 to 30 A/(m·mm)-1,and Hp(x)M ranged from 270 to 300 A/m under the test parameters in this work.After failure,both abnormal peaks of Hp(y) and peak of Hp(x) reversed,K value was 133 A/(m·mm)-1 and Hp(x)M was-640 A/m.The results indicate that the characteristics of Hp(y) and Hp(x) signals were related to the accumulation of fatigue,so it is feasible and applicable to monitor fatigue damage of ferromagnetic components using metal magnetic memory testing(MMMT).
基金Project(2011-0021376) supported by Basic Science Program through the National Research Foundation (NRF) Funded by the Ministry of Education,Science and Technology of Korea
文摘The research goal is to develop a new solar water heater system(SWHS) that uses a solar bubble pump instead of an electric pump.The pump is powered by the steam produced from an evacuated tube collector.Therefore,heat could be transferred downward from the collector to a hot water storage tank.The designed system consists of two sets of heat-pipe evacuated tube collectors,a solar bubble pump installed at an upper level and a water storage tank with a heat exchanger at a lower level.Discharge heads of 1 and 5 m were tested.The bubble pump could operate at the collector temperature of about 90-100 ℃ and vapor gage pressure of 80-90 kPa.It is found that water circulation within the SWHS depends on the incident solar intensity and system discharge head.Experimental investigations are conducted to obtain the system thermal efficiencies from the hourly,daily and long-term performance tests.The thermal performance of the proposed system is compared with conventional solar water heaters.The results show that the proposed system achieves system characteristic efficiency of 10% higher than that of the conventional systems using electric pump if taking the consumption of electric power into account.And the former is a zero carbon system.
文摘Objective： HPP （Hypophosphatasia） is a congenital disease characterized by a deficiency of tissue-specific ALP （alkaline phosphatase）, which causes the generation of abnormal bone and tooth tissue. The clinical manifestations are variable, from neonatal forms with high mortality to milder adult forms with fractures and osteomalacia. The present study reports a clinical case of HPP, with emphasis on the physical characteristics and laboratory tests. The patient was attended at the medical genetics outpatient clinic of the Association of Parents and Friends of the Exceptional of Manaus （Associa？？o de Pais e Amigos dos Excepcionais-APAE/Manaus）. Methodology： For the case report, anamnesis, peripheral blood G-band karyotyping, Vitamin and ALP dosage and resonance examination were performed. Results： A.M.M.S, 9 years, non-consanguineous parents, no bone disease in the family, with one sister from the mother. Birth weight AGA without intercurrence. The patient presented a slight delay in psycho-motor development and was diagnosed with craniostenosis through CNS imaging examination. The physical examination, in addition to a short stature, showed dolichocephaly, frontal bossing, curved tibias and great dental compromise with many early cavities and loss of teeth. Laboratory evaluation： ALP dosage： 63/L （N = 69-325）; Vitamin B6 dosage： 27.4 （5.2-34.1）. The mother and the younger sister also had an ALP result below that expected for the age. Conclusions： The clinical phenotype and laboratory diagnosis of the patient were compatible with ICD Q78 HPP.
文摘The spatial variability of geotechnical earthquake engineering critical parameters obtained by laboratory and in situ tests in the same area is affected by different measurements. The paper provides a brief synthesis of ground motion and site effects analysis procedures within a Performance-Based Design framework. In particular it focuses about the influence on the evaluation of site effects in some active regions by different shear waves velocity measurements （Down Hole D-H and Seismic Dilatometer Marchetti Test SDMT）. Moreover the variation of shear modulus and damping ratio with strain level and depth from different laboratory dynamic or cyclic tests for soil characterisation （Resonant Column Test RCT） was evaluated. The available data enabled one to compare the shear waves velocity profile obtained by laboratory and in situ tests （Cone Penetration Tests CPT） with empirical correlations proposed in literature.
文摘This study is aimed at the thermal analysis of sealant mortar （usually a mixtures of bentonite and cemem with addition of sand） used in geothermal cooling and heating. In particular, thermal conductivity and diffusivity measurements were performed on differem sealant mixtures by using Hot Disk thermal constants analyzer in order to identify the interesting thermal properties of grouting materials. The grouting materials that we considered are of porous nature and, if used in the presence of groundwater, have different levels of imbibitions. It is important to know the thermal behavior of these materials at different water content. A first set of measurements was performed on a not-tinted material at room temperature; then the samples were led to saturation conditions by contact capillary imbibitions with a cotton wool layer moistened in water. The determination of thermal conductivity in these test conditions appears to be critical compared to the measuremems on non-timed sample. The thermal conductivity tests have revealed how the thermal behavior of the samples analyzed is essentially determined by the density and water content of the material： in fact, the thermal conductivity increases of two to three times the value of the not-tinted material.
文摘Measurement of the volume of gas adsorbed per unit mass of coal with increasing pressure at a constant temperature produces an isotherm that describes the gas storage capacity of this type of coal. The accurate testing and interpretation of coal sorption isotherm plays an important role in the areas of coal mine methane drainage, coalbed methane （CBM） reservoir resource assessment, enhanced coalbed methane （ECBM） recovery, as well as the carbon dioxide （CO2） sequestration in deep coal seams or similar geological formations. Different coal sorption isotherm testing apparatus and associated calculation methods are critically reviewed and presented in this paper. These include both volumetric and gravimetric based methods, as well as experimental sorption tests with confining stress and direction sorption methods. The volumetric techniques utilise experimental apparatus with sample cell and injection pump and that with both sample cell and reference cell. Whilst the gravimetric approachesinclude methods with sample cell and suspension magnetic balance and that with both sample cell and reference cell. Different testing methods are compared and discussed in this study. A unique in-house-built coal sorption isotherm testing apparatus at the University of Wollongong was presented together with the calculation method, procedures and experimental results. The isotherm results can be calculated by both Soave-Redlich-Kwong （SRK） equation and calibration cure methods which can be used directly to convert the volume of adsorbed gas in different test conditions to standard condition （NTP）.
文摘An experimental analysis is performed to evaluate Rogowski coil performance for PD （partial discharge） location on overhead CC （covered-conductor） distribution lines. The measuring set-up is arranged in high voltage laboratory. A multi-end measuring method is chosen as a technique to locate PD source point on the line. A power transformer is used to energize one end of the CC line by the AC voltage source. The performance of Rogowski-coil is tested in noisy environment. The tests are carried out conceming different measurement conditions such as off-line and on-line PD measuring systems. The results obtained from the laboratory measurements confirm the capability of the Rogowski-coil in order to measure and locate the high frequency PD source on the CC line in consistent with energizing AC source. Chirp detector is used as a signal-processing tool in order to extract the PD signals and then apply the locator algorithm.
文摘Information on seed vigor of the vegetable crops is always important and necessary due to the increasing demand of high quality seeds for sowing and high-value commercial. The cultivation of these species, conducted intensively, should be established with seed high potential physiological and health for the development of a more productive and sustainable agriculture. The present study was conducted to evaluate the potential physiological of seed lots of radish and coriander. The experiment was conducted at the laboratory of seed analysis and greenhouse of the plant science department of the Federal University of Pelotas in South Brazil. Four radish seed lots, cultivar ＂Saxa＂, and four coriander seed lots, cultivar ＂Verdito＂ were used. Germination seed test, first count of germination, accelerated aging test, electrical conductivity and seedling emergence were used to evaluate the physiological quality of the lots. The experimental design was completely randomized design with five replications. Means were compared by Tukey test. The accelerated aging test was the most efficient test in assessing the physiological quality for both lots of radish seeds and coriander and this test provide coherent results with seedlings emergence.
文摘Objective:To observe the effects of muscle regions of meridians needling method combined with auricular point sticking on pain and lumbar range of motion in patients with chronic nonspecific low back pain.Methods:A total of 100 patients with chronic nonspecific low back pain were randomly divided into a control group and an observation group,with 50 patients in each group.Both groups received auricular point sticking treatment,while the control group received additional conventional acupuncture treatment,and the observation group received additional muscle regions of meridians needling method.The total effective rate of the two groups was compared after 4 weeks of treatment.Before treatment and after 1 week and 4 weeks of treatment,the visual analog scale(VAS)score was used to assess the degree of low back pain,and the modified-modified Schober(MMS)score was used to evaluate the lumbar range of motion.Results:There was statistical significance in comparing the total effective rate between the two groups(P<0.01).During the treatment process,as the number of treatments increased,the VAS score gradually decreased,and the MMS score gradually increased in both groups.After 1 week and 4 weeks of treatment,the VAS score in the observation group was lower than that in the control group(P<0.01),and the MMS score in the observation group was higher than that in the control group(P<0.01).During the treatment period,no serious adverse reactions occurred in either group.Conclusion:Based on auricular point sticking treatment,muscle regions of meridians needling method is more effective than conventional acupuncture in treating chronic nonspecific low back pain since it is able to significantly reduce the pain and improve the lumbar range of motion.
文摘In this paper a critical review is presented of the history and current state of the art of J-integral resistance curve testing and experimental evaluation methods in conjunction with a discussion of the development of the plane strain fracture toughness test standard ASTM E1820 developed by American Society for Testing and Materials (ASTM). Early research efforts on this topic are reviewed first. These include the J-integral concept, experimental estimates of the J-integral for stationary cracks, load line displacement (LLD) and crack mouth opening displacement (CMOD) based η factor equations, different formulations of J-integral incremental equations for growing cracks, crack growth corrected J-R curve determination, and experimental test methods. Recent developments in J-R curve testing and evaluation are then described, with emphasis on accurate J-integral incremental equations, a normalization method, a modified basic method, a CMOD direct method with use of incremental equations, relationships of plastic geometry factors, constraint-dependent J-R curve testing and correction approaches. An overview of the present fracture toughness test standard ASTM E1820-08a is then presented. The review shows that after more than 40 years of investigation and development, the J-integral resistance curve test methods in ASTM E1820 have become simpler, more cost-effective and more accurate.
