Subarachnoid hemorrhage is associated with high morbidity and mortality and lacks effective treatment.Pyroptosis is a crucial mechanism underlying early brain injury after subarachnoid hemorrhage.Previous studies have...Subarachnoid hemorrhage is associated with high morbidity and mortality and lacks effective treatment.Pyroptosis is a crucial mechanism underlying early brain injury after subarachnoid hemorrhage.Previous studies have confirmed that tumor necrosis factor-stimulated gene-6(TSG-6)can exert a neuroprotective effect by suppressing oxidative stress and apoptosis.However,no study to date has explored whether TSG-6 can alleviate pyroptosis in early brain injury after subarachnoid hemorrhage.In this study,a C57BL/6J mouse model of subarachnoid hemorrhage was established using the endovascular perforation method.Our results indicated that TSG-6 expression was predominantly detected in astrocytes,along with NLRC4 and gasdermin-D(GSDMD).The expression of NLRC4,GSDMD and its N-terminal domain(GSDMD-N),and cleaved caspase-1 was significantly enhanced after subarachnoid hemorrhage and accompanied by brain edema and neurological impairment.To explore how TSG-6 affects pyroptosis during early brain injury after subarachnoid hemorrhage,recombinant human TSG-6 or a siRNA targeting TSG-6 was injected into the cerebral ventricles.Exogenous TSG-6 administration downregulated the expression of NLRC4 and pyroptosis-associated proteins and alleviated brain edema and neurological deficits.Moreover,TSG-6 knockdown further increased the expression of NLRC4,which was accompanied by more severe astrocyte pyroptosis.In summary,our study revealed that TSG-6 provides neuroprotection against early brain injury after subarachnoid hemorrhage by suppressing NLRC4 inflammasome activation-induced astrocyte pyroptosis.展开更多
With the rapid development of information and communication technology,a key objective in the field of optoelectronic integrated devices is to reduce the nano-laser size and energy consumption.Photonics nanolasers are...With the rapid development of information and communication technology,a key objective in the field of optoelectronic integrated devices is to reduce the nano-laser size and energy consumption.Photonics nanolasers are unable to exceed the diffraction limit and typically exhibit low modulation rates of several GHz.In contrast,plasmonic nanolaser utilizes highly confined surface plasmon polariton(SPP)mode that can exceed diffraction limit and their strong Purcell effect can accelerate the modulation rates to several THz.Herein,we propose a parametrically tunable artificial plasmonic nanolasers based on metal–insulator–semiconductor–insulator–metal(MISIM)structure,which demonstrates its ability to compress the mode field volume toλ/14.As the pump power increases,the proposed artificial plasmonic nanolaser exhibits 20-nm-wide output spectrum.Additionally,we investigate the effects of various cavity parameters on the nanolaser’s output threshold,offering potentials for realizing low-threshold artificial plasmonic nanolasers.Moreover,we observe a blue shift in the center wavelength of the nanolaser output with thinner gain layer thickness,predominantly attributed to the increased exciton–photon coupling strength.Our work brings inspiration to several areas,including spaser-based interconnects,nano-LEDs,spontaneous emission control,miniaturization of photon condensates,eigenmode engineering of plasmonic nanolasers,and optimal design driven by artificial intelligence(AI).展开更多
The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the...The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k×2k EUV CMOS imaging camera and to take full-disk solar images at the Ne VII 46.5 nm spectral line with a filter width of~3 nm.SUTRI employs a Ritchey-Chrétien optical system with an aperture of 18 cm.The on-orbit observations show that SUTRI images have a field of view of~416×416 and a moderate spatial resolution of~8″without an image stabilization system.The normal cadence of SUTRI images is 30 s and the solar observation time is about16 hr each day because the earth eclipse time accounts for about 1/3 of SATech-01's orbit period.Approximately15 GB data is acquired each day and made available online after processing.SUTRI images are valuable as the Ne VII 46.5 nm line is formed at a temperature regime of~0.5 MK in the solar atmosphere,which has rarely been sampled by existing solar imagers.SUTRI observations will establish connections between structures in the lower solar atmosphere and corona,and advance our understanding of various types of solar activity such as flares,filament eruptions,coronal jets and coronal mass ejections.展开更多
电力线所处环境恶劣,工况复杂,具柔索特性,对巡线机器人的稳定性和可靠性提出较大挑战,因此以飞走巡线机器人(flying-walking power line inspection robot,FPLIR)为研究对象,提出了一种多模式切换混杂控制方法。在FPLIR巡检工作原理基...电力线所处环境恶劣,工况复杂,具柔索特性,对巡线机器人的稳定性和可靠性提出较大挑战,因此以飞走巡线机器人(flying-walking power line inspection robot,FPLIR)为研究对象,提出了一种多模式切换混杂控制方法。在FPLIR巡检工作原理基础上,建立4种控制模式的混杂自动机模型和相互切换的监测器模型;利用Lyapunov函数法和力角稳定性判据(force-angle stability margin,FASM)法分析FPLIR多模式切换和力学特性的稳定性;基于各模式的控制目标,提出了对应的控制策略,尤其结合FPLIR的结构和工况特点,设计变论域模糊控制器,提高FPLIR线上行走的稳定性,设计模型预测控制器,提高FPLIR落线的安全性。最后通过仿真和实验验证了多模式切换混杂控制方法的有效性和可行性,提升了FPLIR在复杂电力线环境下的适应性,为未来机器人智能巡检提供理论参考。展开更多
Objective This study aimed to determine whether the day of blastocyst expansion affects pregnancy outcomes in frozen-thawed blastocyst transfer(FBT)cycles.Methods A retrospective match-cohort study was conducted.Patie...Objective This study aimed to determine whether the day of blastocyst expansion affects pregnancy outcomes in frozen-thawed blastocyst transfer(FBT)cycles.Methods A retrospective match-cohort study was conducted.Patients who underwent blastocyst transfer in frozen-thawed cycles at day 5 or 6 were matched for potential confounding factors.A total of 2207 matched pairs of FBT cycles were included from January 2016 to December 2019 in our Reproductive Medicine Center.Results The clinical pregnancy rate(CPR)and live birth rate(LBR)were significantly increased in day 5 blastocyst transfers when compared to day 6 blastocyst transfers,in terms of the same embryo quality.For FBT cycles with good-quality embryo,the CPR at day 5 and 6 was 61.30%and 57.56%,respectively(P=0.045),and the LBR was 44.79%and 36.16%,respectively(P<0.001).For FBT cycles with poor-quality embryo,the CPR at day 5 and 6 was 48.61%and 40.89%,respectively(P=0.006),and the LBR was 31.71%and 25.74%,respectively(P=0.019).The CPR for FBT cycles with good-quality embryo was statistically higher at day 6 than that at day 5 with poor-quality embryo transferred(57.56%vs.48.61%,P=0.001).Maternal age,anti-Müllerian hormone(AMH),endometrial thickness,embryo quality,and the day of blastocyst expansion were independently correlated with the CPR and LBR.The FBT cycles at day 5 had significantly higher CPR(adjusted odds ratio[OR]=1.246,95%confidence intervals[CI]:1.097–1.415,P=0.001)and LBR(adjusted OR=1.435,95%CI:1.258–1.637,P<0.001)than those at day 6.Conclusion The embryo quality is the primary indicator for FBT cycles.Day 5 blastocysts should be preferred when the quality of embryo at day 5 is the same as that at day 6.展开更多
A grain boundary diffusion(GBD)process with Pr_(80-x)Al_(x)Cu_(20)(x=0,10,15,20)low melting point alloys was applied to commercial 42M sintered Nd–Fe–B magnets.The best coercivity enhancement of a diffused magnet wa...A grain boundary diffusion(GBD)process with Pr_(80-x)Al_(x)Cu_(20)(x=0,10,15,20)low melting point alloys was applied to commercial 42M sintered Nd–Fe–B magnets.The best coercivity enhancement of a diffused magnet was for the Pr_(65)Al_(15)Cu_(20)GBD magnet,from 16.38 kOe to 22.38 kOe.Microstructural investigations indicated that increase in the Al content in the diffusion source can form a continuous grain boundary(GB)phase,optimizing the microstructure to enhance the coercivity.The coercivity enhancement is mainly due to the formation of a continuous GB phase to separate the main phase grains.Exchange decoupling between the adjacent main phase grains is enhanced after the GBD process.Meanwhile,the introduction of Al can effectively promote the infiltration of Pr into the magnet,which increases the diffusion rate of rare-earth elements within a certain range.This work provides a feasible method to enhance coercivity and reduce the use of rare-earth resources by partial replacement of rare-earth elements with non-rare-earth elements in the diffusion source.展开更多
Rechargeable ion batteries require anode materials with excellent performance,presenting a key challenge for researchers.This paper explores the potential of using two-dimensional dumbbell silicene as an anode materia...Rechargeable ion batteries require anode materials with excellent performance,presenting a key challenge for researchers.This paper explores the potential of using two-dimensional dumbbell silicene as an anode material for alkali metal ion batteries through density functional theory(DFT)calculations.Our findings demonstrate that alkali metal ions have negative adsorption energies on dumbbell silicene,and the energy barriers for Li/Na/K ion diffusion are as low as0.032 e V/0.055 e V/0.21 e V,indicating that metal ions can easily diffuse across the entire surface of dumbbell silicene.Additionally,the average open circuit voltages of dumbbell silicene as anode for Li-ion,Na-ion,and K-ion batteries are 0.42 V,0.41 V,and 0.60 V,respectively,with corresponding storage capacities of 716 m Ah/g,622 m Ah/g,and 716 m Ah/g.These results suggest that dumbbell silicene is an ideal anode material for Li-ion,Na-ion,and K-ion batteries,with high capacity,low open circuit voltage,and high ion diffusion kinetics.Moreover,our calculations show that the theoretical capacities obtained using DFT-D2 are higher than those obtained using DFT-D3,providing a valuable reference for subsequent theoretical calculations.展开更多
We studied the magnetic properties and domain evolution of annealed and TbF3-diffused sintered Nd-Fe-B magnets using the electrophoretic deposition method.After TbF_(3)diffusion,the coercivity increased significantly ...We studied the magnetic properties and domain evolution of annealed and TbF3-diffused sintered Nd-Fe-B magnets using the electrophoretic deposition method.After TbF_(3)diffusion,the coercivity increased significantly by 9.9 kOe and microstructural analysis suggested that Tb favored the formation of the(Nd,Tb)_(2)Fe_(14)B shell phase in the outer region of the matrix grains.The first magnetization reversal and the dynamic successive domain propagation process were detected with a magneto-optical Kerr microscope.For the TbF_(3)-diffused magnet,the magnetization reversal appeared at a larger applied field and the degree of simultaneous magnetization reversal decreased compared with an annealed magnet.During demagnetization after full magnetization,the occurrence of domain wall motion(DWM)in the reproduced multi-domain regions was observed by the step method.The maximum polarization change resulting from the reproduced DWM was inversely related to the coercivity.The increased coercivity for the diffused magnet was mainly attributed to the more difficult nucleation of the magnetic reversed region owing to the improved magneto-crystalline anisotropy field as a result of Tb diffusion.展开更多
The thermodynamic equilibrium of deoxidation reactions between molten slag and steel was calculated using a slag-steel coupling thermodynamic model and the mass conservation model based on the ion-molecular coexistenc...The thermodynamic equilibrium of deoxidation reactions between molten slag and steel was calculated using a slag-steel coupling thermodynamic model and the mass conservation model based on the ion-molecular coexistence theory.The study focused on the effects of slag composition and deoxidizer type on the oxygen content of low alloy steel during the electroslag remelting(ESR)process.The measured and predicted values of the oxygen content in remelted ingots,and the contents of FeO and MnO in slags were compared and analyzed.Results show that the measured content of total oxygen has a certain correlation with the trend of dissolved oxygen predicted by the model when using Ca-Si alloys as deoxidizer,but it is not correlated with the trend of dissolved oxygen predicted by the model when using Al as deoxidizer.The deoxidation mechanisms of Ca-Si and Al are different.Ca-Si alloy directly reacts with FeO and MnO in slag to reduce the oxygen potential of slag,hence it can inhibit the transfer of oxygen from the slag to molten steel.While,when Al deoxidizer is used,the oxygen content in steel is mainly reduced through floating up the alumina inclusions.Compared to Al,utilizing Ca-Si alloy as a deoxidizer is more effective in reducing the oxygen content and the amount of inclusions in ESR ingot.展开更多
BACKGROUND Carcinosarcomas of the common bile duct(CBD)are an extremely rare finding in the clinical setting.Based on a review of 12 literatures,3 cases had the imaging features of ossification.Carcinosarcomas are pro...BACKGROUND Carcinosarcomas of the common bile duct(CBD)are an extremely rare finding in the clinical setting.Based on a review of 12 literatures,3 cases had the imaging features of ossification.Carcinosarcomas are prone to distant metastasis,as they possess clinical features of both carcinoma and sarcoma,and generally have with a poor prognosis.Due to the small number of cases reported,clinical experience in the diagnosis and treatment of the disease is lacking.CASE SUMMARY The patient was a 75-year-old woman who had experienced recurrent chills with nausea and vomiting for 3 mo.Computed tomography,magnetic resonance imaging,endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography led to the diagnosis of malignant tumor of the CBD.The patient ultimately underwent cholecystectomy,CBD resection,and choledochojejunostomy.Postoperative pathological examination revealed carcinosarcoma of the CBD,and the latest follow-up showed that the patient is recovering well.Based on previous case reports,some carcinosarcoma has ossification characteristics in imaging.If it is misdiagnosed as biliary calculi,the use of laser lithotripsy in surgery may lead to tumor diffusion.Choledochoscopy and narrow band staining of mucosa are very important for diagnosis.CONCLUSION We herein present a rare case of carcinosarcomas of the CBD,we found the tumours may have imaging features of polypoid growth and ossification only when the sarcomal components are bone differentiation,while show soft tissue shadow when non bone differentiation.Confirmation of diagnosis depends greatly upon postoperative pathological examination and the adjuvant treatment has not been established,which leads to the poor prognosis.展开更多
基金supported the National Natural Science Foundation of China,No.81974178(to CD).
文摘Subarachnoid hemorrhage is associated with high morbidity and mortality and lacks effective treatment.Pyroptosis is a crucial mechanism underlying early brain injury after subarachnoid hemorrhage.Previous studies have confirmed that tumor necrosis factor-stimulated gene-6(TSG-6)can exert a neuroprotective effect by suppressing oxidative stress and apoptosis.However,no study to date has explored whether TSG-6 can alleviate pyroptosis in early brain injury after subarachnoid hemorrhage.In this study,a C57BL/6J mouse model of subarachnoid hemorrhage was established using the endovascular perforation method.Our results indicated that TSG-6 expression was predominantly detected in astrocytes,along with NLRC4 and gasdermin-D(GSDMD).The expression of NLRC4,GSDMD and its N-terminal domain(GSDMD-N),and cleaved caspase-1 was significantly enhanced after subarachnoid hemorrhage and accompanied by brain edema and neurological impairment.To explore how TSG-6 affects pyroptosis during early brain injury after subarachnoid hemorrhage,recombinant human TSG-6 or a siRNA targeting TSG-6 was injected into the cerebral ventricles.Exogenous TSG-6 administration downregulated the expression of NLRC4 and pyroptosis-associated proteins and alleviated brain edema and neurological deficits.Moreover,TSG-6 knockdown further increased the expression of NLRC4,which was accompanied by more severe astrocyte pyroptosis.In summary,our study revealed that TSG-6 provides neuroprotection against early brain injury after subarachnoid hemorrhage by suppressing NLRC4 inflammasome activation-induced astrocyte pyroptosis.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12174037,12204061,12204030,and 62375003)the Fundamental Research Funds for the Central Universities,China(Grant No.2022XD-A09)the Fund from the State Key Laboratory of Information Photonics and Optical Communication,China(Grant No.IPOC2021ZZ02)。
文摘With the rapid development of information and communication technology,a key objective in the field of optoelectronic integrated devices is to reduce the nano-laser size and energy consumption.Photonics nanolasers are unable to exceed the diffraction limit and typically exhibit low modulation rates of several GHz.In contrast,plasmonic nanolaser utilizes highly confined surface plasmon polariton(SPP)mode that can exceed diffraction limit and their strong Purcell effect can accelerate the modulation rates to several THz.Herein,we propose a parametrically tunable artificial plasmonic nanolasers based on metal–insulator–semiconductor–insulator–metal(MISIM)structure,which demonstrates its ability to compress the mode field volume toλ/14.As the pump power increases,the proposed artificial plasmonic nanolaser exhibits 20-nm-wide output spectrum.Additionally,we investigate the effects of various cavity parameters on the nanolaser’s output threshold,offering potentials for realizing low-threshold artificial plasmonic nanolasers.Moreover,we observe a blue shift in the center wavelength of the nanolaser output with thinner gain layer thickness,predominantly attributed to the increased exciton–photon coupling strength.Our work brings inspiration to several areas,including spaser-based interconnects,nano-LEDs,spontaneous emission control,miniaturization of photon condensates,eigenmode engineering of plasmonic nanolasers,and optimal design driven by artificial intelligence(AI).
基金supported by the National Natural Science Foundation of China(NSFC)under Grants 11825301,12003016,12073077the National Key R&D Program of China No.2021YFA0718600+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences with the Grant No.XDA15018400the Youth Innovation Promotion Association of CAS(2023061)。
文摘The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k×2k EUV CMOS imaging camera and to take full-disk solar images at the Ne VII 46.5 nm spectral line with a filter width of~3 nm.SUTRI employs a Ritchey-Chrétien optical system with an aperture of 18 cm.The on-orbit observations show that SUTRI images have a field of view of~416×416 and a moderate spatial resolution of~8″without an image stabilization system.The normal cadence of SUTRI images is 30 s and the solar observation time is about16 hr each day because the earth eclipse time accounts for about 1/3 of SATech-01's orbit period.Approximately15 GB data is acquired each day and made available online after processing.SUTRI images are valuable as the Ne VII 46.5 nm line is formed at a temperature regime of~0.5 MK in the solar atmosphere,which has rarely been sampled by existing solar imagers.SUTRI observations will establish connections between structures in the lower solar atmosphere and corona,and advance our understanding of various types of solar activity such as flares,filament eruptions,coronal jets and coronal mass ejections.
文摘电力线所处环境恶劣,工况复杂,具柔索特性,对巡线机器人的稳定性和可靠性提出较大挑战,因此以飞走巡线机器人(flying-walking power line inspection robot,FPLIR)为研究对象,提出了一种多模式切换混杂控制方法。在FPLIR巡检工作原理基础上,建立4种控制模式的混杂自动机模型和相互切换的监测器模型;利用Lyapunov函数法和力角稳定性判据(force-angle stability margin,FASM)法分析FPLIR多模式切换和力学特性的稳定性;基于各模式的控制目标,提出了对应的控制策略,尤其结合FPLIR的结构和工况特点,设计变论域模糊控制器,提高FPLIR线上行走的稳定性,设计模型预测控制器,提高FPLIR落线的安全性。最后通过仿真和实验验证了多模式切换混杂控制方法的有效性和可行性,提升了FPLIR在复杂电力线环境下的适应性,为未来机器人智能巡检提供理论参考。
基金supported by the National Natural Science Foundation of China(No.81701509).
文摘Objective This study aimed to determine whether the day of blastocyst expansion affects pregnancy outcomes in frozen-thawed blastocyst transfer(FBT)cycles.Methods A retrospective match-cohort study was conducted.Patients who underwent blastocyst transfer in frozen-thawed cycles at day 5 or 6 were matched for potential confounding factors.A total of 2207 matched pairs of FBT cycles were included from January 2016 to December 2019 in our Reproductive Medicine Center.Results The clinical pregnancy rate(CPR)and live birth rate(LBR)were significantly increased in day 5 blastocyst transfers when compared to day 6 blastocyst transfers,in terms of the same embryo quality.For FBT cycles with good-quality embryo,the CPR at day 5 and 6 was 61.30%and 57.56%,respectively(P=0.045),and the LBR was 44.79%and 36.16%,respectively(P<0.001).For FBT cycles with poor-quality embryo,the CPR at day 5 and 6 was 48.61%and 40.89%,respectively(P=0.006),and the LBR was 31.71%and 25.74%,respectively(P=0.019).The CPR for FBT cycles with good-quality embryo was statistically higher at day 6 than that at day 5 with poor-quality embryo transferred(57.56%vs.48.61%,P=0.001).Maternal age,anti-Müllerian hormone(AMH),endometrial thickness,embryo quality,and the day of blastocyst expansion were independently correlated with the CPR and LBR.The FBT cycles at day 5 had significantly higher CPR(adjusted odds ratio[OR]=1.246,95%confidence intervals[CI]:1.097–1.415,P=0.001)and LBR(adjusted OR=1.435,95%CI:1.258–1.637,P<0.001)than those at day 6.Conclusion The embryo quality is the primary indicator for FBT cycles.Day 5 blastocysts should be preferred when the quality of embryo at day 5 is the same as that at day 6.
基金Project supported by the National Key Research and Development Program of China (Grant No.2021YFB3502802)Major Science and Technology Research and Development Project of Jiangxi Province,China (Grant No.20203ABC28W006)+2 种基金the Key Research and Development Program of Shandong Province,China (Grant No.2019JZZY010321)Major Project of“Science and Technology Innovation 2025”in Ningbo City (Grant No.2020Z046)the K.C.Wong Magna Fund in Ningbo University。
文摘A grain boundary diffusion(GBD)process with Pr_(80-x)Al_(x)Cu_(20)(x=0,10,15,20)low melting point alloys was applied to commercial 42M sintered Nd–Fe–B magnets.The best coercivity enhancement of a diffused magnet was for the Pr_(65)Al_(15)Cu_(20)GBD magnet,from 16.38 kOe to 22.38 kOe.Microstructural investigations indicated that increase in the Al content in the diffusion source can form a continuous grain boundary(GB)phase,optimizing the microstructure to enhance the coercivity.The coercivity enhancement is mainly due to the formation of a continuous GB phase to separate the main phase grains.Exchange decoupling between the adjacent main phase grains is enhanced after the GBD process.Meanwhile,the introduction of Al can effectively promote the infiltration of Pr into the magnet,which increases the diffusion rate of rare-earth elements within a certain range.This work provides a feasible method to enhance coercivity and reduce the use of rare-earth resources by partial replacement of rare-earth elements with non-rare-earth elements in the diffusion source.
基金the National Natural Science Foundation of China(Grant No.12274112)the Overseas Scientists Sponsorship Program of Hebei Province of China(Grant No.C20210330)the State Key Laboratory of Reliability and Intelligence of Electrical Equipment of Hebei University of Technology(Grant No.EERI PI2020009)。
文摘Rechargeable ion batteries require anode materials with excellent performance,presenting a key challenge for researchers.This paper explores the potential of using two-dimensional dumbbell silicene as an anode material for alkali metal ion batteries through density functional theory(DFT)calculations.Our findings demonstrate that alkali metal ions have negative adsorption energies on dumbbell silicene,and the energy barriers for Li/Na/K ion diffusion are as low as0.032 e V/0.055 e V/0.21 e V,indicating that metal ions can easily diffuse across the entire surface of dumbbell silicene.Additionally,the average open circuit voltages of dumbbell silicene as anode for Li-ion,Na-ion,and K-ion batteries are 0.42 V,0.41 V,and 0.60 V,respectively,with corresponding storage capacities of 716 m Ah/g,622 m Ah/g,and 716 m Ah/g.These results suggest that dumbbell silicene is an ideal anode material for Li-ion,Na-ion,and K-ion batteries,with high capacity,low open circuit voltage,and high ion diffusion kinetics.Moreover,our calculations show that the theoretical capacities obtained using DFT-D2 are higher than those obtained using DFT-D3,providing a valuable reference for subsequent theoretical calculations.
基金the National Natural Science Foundation of China(Grant No.52101238)the“Pioneer”and“Leading Goose”Research and Development Program of Zhejiang(Grant No.2021C01190)Major Project of Ningbo Science and Technology Innovation 2025(Grant No.2020Z046)。
文摘We studied the magnetic properties and domain evolution of annealed and TbF3-diffused sintered Nd-Fe-B magnets using the electrophoretic deposition method.After TbF_(3)diffusion,the coercivity increased significantly by 9.9 kOe and microstructural analysis suggested that Tb favored the formation of the(Nd,Tb)_(2)Fe_(14)B shell phase in the outer region of the matrix grains.The first magnetization reversal and the dynamic successive domain propagation process were detected with a magneto-optical Kerr microscope.For the TbF_(3)-diffused magnet,the magnetization reversal appeared at a larger applied field and the degree of simultaneous magnetization reversal decreased compared with an annealed magnet.During demagnetization after full magnetization,the occurrence of domain wall motion(DWM)in the reproduced multi-domain regions was observed by the step method.The maximum polarization change resulting from the reproduced DWM was inversely related to the coercivity.The increased coercivity for the diffused magnet was mainly attributed to the more difficult nucleation of the magnetic reversed region owing to the improved magneto-crystalline anisotropy field as a result of Tb diffusion.
文摘The thermodynamic equilibrium of deoxidation reactions between molten slag and steel was calculated using a slag-steel coupling thermodynamic model and the mass conservation model based on the ion-molecular coexistence theory.The study focused on the effects of slag composition and deoxidizer type on the oxygen content of low alloy steel during the electroslag remelting(ESR)process.The measured and predicted values of the oxygen content in remelted ingots,and the contents of FeO and MnO in slags were compared and analyzed.Results show that the measured content of total oxygen has a certain correlation with the trend of dissolved oxygen predicted by the model when using Ca-Si alloys as deoxidizer,but it is not correlated with the trend of dissolved oxygen predicted by the model when using Al as deoxidizer.The deoxidation mechanisms of Ca-Si and Al are different.Ca-Si alloy directly reacts with FeO and MnO in slag to reduce the oxygen potential of slag,hence it can inhibit the transfer of oxygen from the slag to molten steel.While,when Al deoxidizer is used,the oxygen content in steel is mainly reduced through floating up the alumina inclusions.Compared to Al,utilizing Ca-Si alloy as a deoxidizer is more effective in reducing the oxygen content and the amount of inclusions in ESR ingot.
文摘BACKGROUND Carcinosarcomas of the common bile duct(CBD)are an extremely rare finding in the clinical setting.Based on a review of 12 literatures,3 cases had the imaging features of ossification.Carcinosarcomas are prone to distant metastasis,as they possess clinical features of both carcinoma and sarcoma,and generally have with a poor prognosis.Due to the small number of cases reported,clinical experience in the diagnosis and treatment of the disease is lacking.CASE SUMMARY The patient was a 75-year-old woman who had experienced recurrent chills with nausea and vomiting for 3 mo.Computed tomography,magnetic resonance imaging,endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography led to the diagnosis of malignant tumor of the CBD.The patient ultimately underwent cholecystectomy,CBD resection,and choledochojejunostomy.Postoperative pathological examination revealed carcinosarcoma of the CBD,and the latest follow-up showed that the patient is recovering well.Based on previous case reports,some carcinosarcoma has ossification characteristics in imaging.If it is misdiagnosed as biliary calculi,the use of laser lithotripsy in surgery may lead to tumor diffusion.Choledochoscopy and narrow band staining of mucosa are very important for diagnosis.CONCLUSION We herein present a rare case of carcinosarcomas of the CBD,we found the tumours may have imaging features of polypoid growth and ossification only when the sarcomal components are bone differentiation,while show soft tissue shadow when non bone differentiation.Confirmation of diagnosis depends greatly upon postoperative pathological examination and the adjuvant treatment has not been established,which leads to the poor prognosis.
