Lead zirconate titanate(PZT)ceramics possess great potential for practical applications and thus improving their piezoelectric properties is crucial.Pb0.99−xSm0.01BaxZr0.53Ti0.47O3(PSBZT)ceramics with high Curie tempe...Lead zirconate titanate(PZT)ceramics possess great potential for practical applications and thus improving their piezoelectric properties is crucial.Pb0.99−xSm0.01BaxZr0.53Ti0.47O3(PSBZT)ceramics with high Curie temperature and excellent piezoelectric properties were fabricated via a conventional solid-state method,and the effect of Ba2+doping on the structural,dielectric,piezoelectric and ferroelectric properties was studied in detail.It is shown that doping of Ba2+significantly enhanced the piezoelectric properties of PSZT,the maximum d33~533 pC/N and Tc~361°C at x=0.02 were acquired.Furthermore,PSZT and PSBZT ceramics were used to prepare single element ultrasonic transducers,and their performance were compared and evaluated.The results demonstrate that the PSBZT ceramic-based transducer possesses better sensitivity and bandwidth than the PSZT ceramic-based transducer.展开更多
In this paper,0.36Pb(Ni_(1/3)Nb_(2/3))O_(3)-0.24PbZrO3-0.40PbTiO_(3)(PNN-PZT)ceramic was prepared,and texture engineering was performed on this PNN-PZT ceramic to improve its electromechanical properties and temperatu...In this paper,0.36Pb(Ni_(1/3)Nb_(2/3))O_(3)-0.24PbZrO3-0.40PbTiO_(3)(PNN-PZT)ceramic was prepared,and texture engineering was performed on this PNN-PZT ceramic to improve its electromechanical properties and temperature stability.Single element ultra-sonic transducers were prepared using PNN-PZT,PNN-PZT textured ceramics,and their performance were evaluated and com-pared using a PZT-5H ceramic based transducer as the benchmark.It is shown that the sensitivity and bandwidth of the PNN-PZT textured ceramic-based transducer are much superior to regular PNN-PZT ceramic and PZT-5H ceramic based transducers.展开更多
Relaxor-based ternary Pb(In1/2Nb1/2)O_(3)-Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PIN-PMN-PT)single crystals and ceramics are promising candidates for high-performance electromechanical conversion devices.It is know...Relaxor-based ternary Pb(In1/2Nb1/2)O_(3)-Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PIN-PMN-PT)single crystals and ceramics are promising candidates for high-performance electromechanical conversion devices.It is known that the domain structure and dielectric diffusion-relaxation characteristics are crucial to the excellent performances of relaxor ferroelectrics.In this work,we prepared the PIN-PMN-PT ceramics with various PIN/PMN proportions and systematically investigated their domain structure and dielectric diffusion-relaxation properties.The effect of PIN/PMN proportion on the domain size and dielectric diffusion-relaxation characteristics was also studied.The investigations showed that PIN-PMN-PT ceramics presented multi-type domain patterns comprising irregular island domains and regular lamellar domains.Moreover,the dependent relations of PIN/PMN proportions on the dielectric diffusion and domain size indicated that the PIN composition has a stronger lattice distortion than PMN composition;increasing the PIN proportion can enhance the dielectric diffusion and decrease the domain size.Our results could deepen the understanding of structure-property relationships of multicomponent relaxor ferroelectrics and guide the design and exploration of new high-performance ferroelectric materials.展开更多
BACKGROUND Colon cancer is associated with a higher incidence among residents in highaltitude areas.Hypoxic environment at high altitudes inhibits the phagocytic and oxygen-dependent killing function of phagocytes,the...BACKGROUND Colon cancer is associated with a higher incidence among residents in highaltitude areas.Hypoxic environment at high altitudes inhibits the phagocytic and oxygen-dependent killing function of phagocytes,thereby increasing the inflammatory factors,inhibiting the body’s innate immunity and increasing the risk of colon cancer.AIM To examine the effect of minimally invasive surgery vs laparotomy in patients with colon cancer residing in high-altitude areas.METHODS Ninety-two patients with colon cancer in our hospital from January 2019 to February 2021 were selected and divided into the minimally invasive surgery and laparotomy groups using the random number table method,with 46 patients in each group.Minimally invasive surgery was performed in the minimally invasive group and laparotomy in the laparotomy group.Operative conditions,inflammatory index pre-and post-surgery,immune function index and complication probability were measured.RESULTS Operative duration was significantly longer and intraoperative blood loss and recovery time of gastrointestinal function were significantly less(all P<0.05)in the minimally invasive group than in the laparotomy group.The number of lymph nodes dissected was not significantly different.Before surgery,there were no significant differences in serum C-reactive protein,interleukin-6 and tumor necrosis factor-αlevels between the groups,whereas after surgery,the levels were significantly higher in the minimally invasive group(26.98±6.91 mg/L,146.38±11.23 ng/mL and 83.51±8.69 pg/mL vs 41.15±8.39 mg/L,186.79±15.36 ng/mL and 110.65±12.84 pg/mL,respectively,P<0.05).Furthermore,before surgery,there were no significant differences in CD3+,CD4+and CD4+/CD8+levels between the groups,whereas after surgery,the levels decreased in both groups,being significantly higher in the minimally invasive group(55.61%±4.39%,35.45%±3.67%and 1.30±0.35 vs 49.68%±5.33%,31.21%±3.25%and 1.13±0.30,respectively,P<0.05).Complication probability was significantly lower in the minimally invasiv展开更多
基金financially supported by the National Natural Science Foundation of China(Grant Nos.11404321,52172085 and 51572056).
文摘Lead zirconate titanate(PZT)ceramics possess great potential for practical applications and thus improving their piezoelectric properties is crucial.Pb0.99−xSm0.01BaxZr0.53Ti0.47O3(PSBZT)ceramics with high Curie temperature and excellent piezoelectric properties were fabricated via a conventional solid-state method,and the effect of Ba2+doping on the structural,dielectric,piezoelectric and ferroelectric properties was studied in detail.It is shown that doping of Ba2+significantly enhanced the piezoelectric properties of PSZT,the maximum d33~533 pC/N and Tc~361°C at x=0.02 were acquired.Furthermore,PSZT and PSBZT ceramics were used to prepare single element ultrasonic transducers,and their performance were compared and evaluated.The results demonstrate that the PSBZT ceramic-based transducer possesses better sensitivity and bandwidth than the PSZT ceramic-based transducer.
基金This work was supported by the National Natural Science Foundation of China(Grant No.51975160).
文摘In this paper,0.36Pb(Ni_(1/3)Nb_(2/3))O_(3)-0.24PbZrO3-0.40PbTiO_(3)(PNN-PZT)ceramic was prepared,and texture engineering was performed on this PNN-PZT ceramic to improve its electromechanical properties and temperature stability.Single element ultra-sonic transducers were prepared using PNN-PZT,PNN-PZT textured ceramics,and their performance were evaluated and com-pared using a PZT-5H ceramic based transducer as the benchmark.It is shown that the sensitivity and bandwidth of the PNN-PZT textured ceramic-based transducer are much superior to regular PNN-PZT ceramic and PZT-5H ceramic based transducers.
基金supported by the National Natural Science Foundation of China(Grant No.11974093)Open Project Program of Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices(EFMD2022006Z)Heilongjiang Touyan Innovation Team Program(XNAUEA5640201720-09).X。
文摘Relaxor-based ternary Pb(In1/2Nb1/2)O_(3)-Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PIN-PMN-PT)single crystals and ceramics are promising candidates for high-performance electromechanical conversion devices.It is known that the domain structure and dielectric diffusion-relaxation characteristics are crucial to the excellent performances of relaxor ferroelectrics.In this work,we prepared the PIN-PMN-PT ceramics with various PIN/PMN proportions and systematically investigated their domain structure and dielectric diffusion-relaxation properties.The effect of PIN/PMN proportion on the domain size and dielectric diffusion-relaxation characteristics was also studied.The investigations showed that PIN-PMN-PT ceramics presented multi-type domain patterns comprising irregular island domains and regular lamellar domains.Moreover,the dependent relations of PIN/PMN proportions on the dielectric diffusion and domain size indicated that the PIN composition has a stronger lattice distortion than PMN composition;increasing the PIN proportion can enhance the dielectric diffusion and decrease the domain size.Our results could deepen the understanding of structure-property relationships of multicomponent relaxor ferroelectrics and guide the design and exploration of new high-performance ferroelectric materials.
基金the People’s Hospital of Tibet Autonomous Region Institutional Review Board(Approval No.METBHP-21-KJ-025).
文摘BACKGROUND Colon cancer is associated with a higher incidence among residents in highaltitude areas.Hypoxic environment at high altitudes inhibits the phagocytic and oxygen-dependent killing function of phagocytes,thereby increasing the inflammatory factors,inhibiting the body’s innate immunity and increasing the risk of colon cancer.AIM To examine the effect of minimally invasive surgery vs laparotomy in patients with colon cancer residing in high-altitude areas.METHODS Ninety-two patients with colon cancer in our hospital from January 2019 to February 2021 were selected and divided into the minimally invasive surgery and laparotomy groups using the random number table method,with 46 patients in each group.Minimally invasive surgery was performed in the minimally invasive group and laparotomy in the laparotomy group.Operative conditions,inflammatory index pre-and post-surgery,immune function index and complication probability were measured.RESULTS Operative duration was significantly longer and intraoperative blood loss and recovery time of gastrointestinal function were significantly less(all P<0.05)in the minimally invasive group than in the laparotomy group.The number of lymph nodes dissected was not significantly different.Before surgery,there were no significant differences in serum C-reactive protein,interleukin-6 and tumor necrosis factor-αlevels between the groups,whereas after surgery,the levels were significantly higher in the minimally invasive group(26.98±6.91 mg/L,146.38±11.23 ng/mL and 83.51±8.69 pg/mL vs 41.15±8.39 mg/L,186.79±15.36 ng/mL and 110.65±12.84 pg/mL,respectively,P<0.05).Furthermore,before surgery,there were no significant differences in CD3+,CD4+and CD4+/CD8+levels between the groups,whereas after surgery,the levels decreased in both groups,being significantly higher in the minimally invasive group(55.61%±4.39%,35.45%±3.67%and 1.30±0.35 vs 49.68%±5.33%,31.21%±3.25%and 1.13±0.30,respectively,P<0.05).Complication probability was significantly lower in the minimally invasiv
