Dissimilar joints(DSJs)of ferrous and non-ferrous metals have huge technological importance in the frontiers of newdesigns in new machineries and improved design of conventional systems.This investigation was undertak...Dissimilar joints(DSJs)of ferrous and non-ferrous metals have huge technological importance in the frontiers of newdesigns in new machineries and improved design of conventional systems.This investigation was undertaken to improve mechanicalproperties of joints of two dissimilar metals:one is Ti-based and the other is Fe-based.DSJs were processed using bonding pressurefrom1to9MPa in step of2MPa at750°C for60min.Properties of the DSJs of these two metals using different mechanisms andmethods were compared with the present research for verification.Experimental results from the diffusion bonding mechanism forjoining the dissimilar metals validated the improvement in properties.Superior mechanical properties of dissimilar-metals joints wereachieved mainly due to the third non-ferrous metallic foil,Ni of^200-?m thickness,which avoided the formation of brittleFe-Ti-based intermetallics in the diffusion zone.DSJs processed are able to achieve maximum strength of^560MPa along withsubstantial ductility of^11.9%,which is the best ever reported in the literatures so far.Work hardening effect was detected in theDSJs when the bonding was processed at5MPa and above.Bulging ratio of the non-ferrous metal(Ti-based)was much higher thanthat of the ferrous metal(SS)of the DSJs processed.SEM analysis was carried out to know the details of reaction zone,while XRDwas carried out to support the SEM results.Reasons for change in mechanical,physical,and fracture properties of the DSJs with theprocess parameter variations were clarified.展开更多
A conveyor belt driven by wound rotor motors produces dynamic tension, velocity and accelerationduring starting. The terrible situation (such as resonance) in dynamic analysis and design is that system naturalfrequenc...A conveyor belt driven by wound rotor motors produces dynamic tension, velocity and accelerationduring starting. The terrible situation (such as resonance) in dynamic analysis and design is that system naturalfrequencies are equal to those for switching off electric resistances. This paper analyzes and determines systemnatural frequencies based on a modeling method of receptances with the analysis of sub-systems model and of theprinciple of their addition and conveyor loop closure. It also puts forward to calculate the time interval for switching off electric resistances. The starting of one conveyor is simulated by lumped-mass-spring-model software tofurther illustrate the influence of time interval for switching off electric resistances on conveyor dynamic behavior. Two methods are also compared. The receptance model is proved to be an excellent alternative.展开更多
Crohn's disease and ulcerative colitis evolve with a relapsing and remitting course.Determination of inflammatory state is crucial for the assessment of disease activity and for tailoring therapy.However,no simple...Crohn's disease and ulcerative colitis evolve with a relapsing and remitting course.Determination of inflammatory state is crucial for the assessment of disease activity and for tailoring therapy.However,no simple diagnostic test for monitoring intestinal inflammation is available.Noninvasive markers give only indirect assessments of disease activity.Histopathological or endoscopical examinations accurately assess inflammatory activity,but they are invasive,time consuming and expensive and therefore are unsuitable for routine use.Imaging procedures are not applicable for ulcerative colitis.The usefulness of ultrasound and Doppler imag-ing in assessing disease activity is still a matter of discussion for Crohn's disease,and an increased interest in computed tomography enterograph (CTE) has been seen,mainly because it can delineate the extent and severity of bowel wall inflammation,besides detecting extraluminal findings.Until now,the available data concerning the accuracy of magnetic resonance enterography in detecting disease activity is less than CTE.Due to this,clinical activity indices are still commonly used for both diseases.展开更多
To alleviate problems with access and affordability,six targeted anticancer medications(TAMs)were listed in the Provincial Reimbursement Drug List(PRDL)for the first time in Zhejiang,China in February 2015.In the pres...To alleviate problems with access and affordability,six targeted anticancer medications(TAMs)were listed in the Provincial Reimbursement Drug List(PRDL)for the first time in Zhejiang,China in February 2015.In the present study,we aimed to evaluate the implementation of the PRDL policy on TAMs use.Using the pharmaceutical procurement data of these six listed TAMs(study group)and four unlisted TAMs(control group)from 22 tertiary hospitals in Zhejiang,China dated between January 2014 and February 2017,interrupted time-series analysis was adopted to examine differences in the average hospital purchasing volume(HPV)and the average hospital purchasing spending(HPS)between the two groups.The average daily cost of listed TAMs in the study group was decreased after April 2015.After enlistment,the average HPV per month was significantly increased by 34.6 defined daily doses(DDDs)(P<0.001),and the average HPS per month was significantly increased by USD 6614.9(P<0.001)for the listed TAMs in the study group(n=6).Neither the average HPV nor the average HPS changed significantly for the unlisted TAMs in the control group(n=4).The PRDL policy showed positive effects on improving patients’affordability and promoting access to TAMs in Zhejiang.The government should conduct further price negotiations and include more TAMs with clinical benefits into reimbursement schemes to relieve patients’financial burden and promote access.展开更多
文摘Dissimilar joints(DSJs)of ferrous and non-ferrous metals have huge technological importance in the frontiers of newdesigns in new machineries and improved design of conventional systems.This investigation was undertaken to improve mechanicalproperties of joints of two dissimilar metals:one is Ti-based and the other is Fe-based.DSJs were processed using bonding pressurefrom1to9MPa in step of2MPa at750°C for60min.Properties of the DSJs of these two metals using different mechanisms andmethods were compared with the present research for verification.Experimental results from the diffusion bonding mechanism forjoining the dissimilar metals validated the improvement in properties.Superior mechanical properties of dissimilar-metals joints wereachieved mainly due to the third non-ferrous metallic foil,Ni of^200-?m thickness,which avoided the formation of brittleFe-Ti-based intermetallics in the diffusion zone.DSJs processed are able to achieve maximum strength of^560MPa along withsubstantial ductility of^11.9%,which is the best ever reported in the literatures so far.Work hardening effect was detected in theDSJs when the bonding was processed at5MPa and above.Bulging ratio of the non-ferrous metal(Ti-based)was much higher thanthat of the ferrous metal(SS)of the DSJs processed.SEM analysis was carried out to know the details of reaction zone,while XRDwas carried out to support the SEM results.Reasons for change in mechanical,physical,and fracture properties of the DSJs with theprocess parameter variations were clarified.
文摘A conveyor belt driven by wound rotor motors produces dynamic tension, velocity and accelerationduring starting. The terrible situation (such as resonance) in dynamic analysis and design is that system naturalfrequencies are equal to those for switching off electric resistances. This paper analyzes and determines systemnatural frequencies based on a modeling method of receptances with the analysis of sub-systems model and of theprinciple of their addition and conveyor loop closure. It also puts forward to calculate the time interval for switching off electric resistances. The starting of one conveyor is simulated by lumped-mass-spring-model software tofurther illustrate the influence of time interval for switching off electric resistances on conveyor dynamic behavior. Two methods are also compared. The receptance model is proved to be an excellent alternative.
文摘Crohn's disease and ulcerative colitis evolve with a relapsing and remitting course.Determination of inflammatory state is crucial for the assessment of disease activity and for tailoring therapy.However,no simple diagnostic test for monitoring intestinal inflammation is available.Noninvasive markers give only indirect assessments of disease activity.Histopathological or endoscopical examinations accurately assess inflammatory activity,but they are invasive,time consuming and expensive and therefore are unsuitable for routine use.Imaging procedures are not applicable for ulcerative colitis.The usefulness of ultrasound and Doppler imag-ing in assessing disease activity is still a matter of discussion for Crohn's disease,and an increased interest in computed tomography enterograph (CTE) has been seen,mainly because it can delineate the extent and severity of bowel wall inflammation,besides detecting extraluminal findings.Until now,the available data concerning the accuracy of magnetic resonance enterography in detecting disease activity is less than CTE.Due to this,clinical activity indices are still commonly used for both diseases.
文摘To alleviate problems with access and affordability,six targeted anticancer medications(TAMs)were listed in the Provincial Reimbursement Drug List(PRDL)for the first time in Zhejiang,China in February 2015.In the present study,we aimed to evaluate the implementation of the PRDL policy on TAMs use.Using the pharmaceutical procurement data of these six listed TAMs(study group)and four unlisted TAMs(control group)from 22 tertiary hospitals in Zhejiang,China dated between January 2014 and February 2017,interrupted time-series analysis was adopted to examine differences in the average hospital purchasing volume(HPV)and the average hospital purchasing spending(HPS)between the two groups.The average daily cost of listed TAMs in the study group was decreased after April 2015.After enlistment,the average HPV per month was significantly increased by 34.6 defined daily doses(DDDs)(P<0.001),and the average HPS per month was significantly increased by USD 6614.9(P<0.001)for the listed TAMs in the study group(n=6).Neither the average HPV nor the average HPS changed significantly for the unlisted TAMs in the control group(n=4).The PRDL policy showed positive effects on improving patients’affordability and promoting access to TAMs in Zhejiang.The government should conduct further price negotiations and include more TAMs with clinical benefits into reimbursement schemes to relieve patients’financial burden and promote access.
