The adsorption characteristics and mechanisms of modified sepiolite as an adsorbent to recover Pd(Ⅱ) from acidic solutions were studied. The Pd(Ⅱ) adsorption properties were analyzed through isotherm, kinetic and th...The adsorption characteristics and mechanisms of modified sepiolite as an adsorbent to recover Pd(Ⅱ) from acidic solutions were studied. The Pd(Ⅱ) adsorption properties were analyzed through isotherm, kinetic and thermodynamic models. In addition, SEM-EDS, TEM and XPS were applied to investigating the Pd(Ⅱ) adsorption mechanisms onto modified sepiolite. The equilibrium data were well fitted to Langmuir isotherm model with maximum Pd(Ⅱ) adsorption capacity of 322.58 mg/g at 30 ℃. The kinetic data could be satisfactorily simulated by the pseudosecond order model, indicating that the rate-controlling step was chemical adsorption. 99% of Pd(Ⅱ) could be recovered using 1 g/L modified sepiolite when initial concentration of Pd(Ⅱ) was 100 mg/L. The results of reusability studies indicated the modified sepiolite had an acceptable stability and reusability. This study indicated that the modified sepiolite might be an efficient and cost-effective material for Pd(Ⅱ) recovery.展开更多
Nd(DBM)3Phen-doped (DBM is dibenzoylmethane and Phen is phenanthroline) polymethyl methacrylate (PMMA) is prepared. Optical absorption, excitation and emission spectra were analyzed for Nd^3+ in Nd(DBM)3Phen-...Nd(DBM)3Phen-doped (DBM is dibenzoylmethane and Phen is phenanthroline) polymethyl methacrylate (PMMA) is prepared. Optical absorption, excitation and emission spectra were analyzed for Nd^3+ in Nd(DBM)3Phen-doped PMMA. Using the Judd-Ofelt theory, the absorption spectrum was analyzed. The Judd-Ofelt(J-O) intensity parameters of Nd(DBM)3Phen-doped polymethyl methacrylate were calculated to be Ω2 = 20.97 × 10^-20 cm^2, Ω4= 3.42 × 10^-20 cm^2, Ω6 = 2.90 × 10^-20 cm^2. The radiative lifetime (631 μs) of the excited 4F3/2 level is given. The stimulated emission cross-sections and the fluorescence branch ratios for the ^4F3/2 →^4Ij′ transitions are also evaluated. Analysis reveals that Nd(DBM)3Phen-doped PMMA is promising for application in polymer optical fibers and planar waveguides.展开更多
A 67-year-old man from Jingzhou was admitted to the First Hospital Affiliated to Yangtze University in July 2013 with sudden onset of abdominal pain with dizziness for 12 h.The patient had sign of peritoneal irritatio...A 67-year-old man from Jingzhou was admitted to the First Hospital Affiliated to Yangtze University in July 2013 with sudden onset of abdominal pain with dizziness for 12 h.The patient had sign of peritoneal irritation.Ultrasonography of the abdomen and pelvis showed hepatic fibrosis due to schistosomiasis.Computed tomography showed free gas in the peritoneal cavity.Plain abdominal radiography showed bilateral subdiaphragmatic accumulation of gas, perforation of the viscus, and radio-opacity in the left renal area.The patient underwent emergency exploratory laparotomy.At laparotomy, a moderate amount of muddy yellow pus was found in the intra-abdominal cavity.At the junction of the jejunum and ileum, about 250 cm from Treitz's ligament, there was an about 10-cm length of inflamed small bowel with perforation(3 mm in diameter) along the mesenteric border at the middle of the lesion.The patient underwent resection of the affected intestinal segment, along with end-to-end intestinal anastomosis.Histopathological examination revealed mucosal necrosis and hemorrhage with a large number of infiltrating eosinophils and neutrophils, and acute submucosal inflammation with a large number of infiltrating eosinophils and neutrophils associated with Schistosoma japonicum(S.japonicum) eggs.No intravascular adult parasite was found.Postoperatively, the patient was treated with praziquantel(30 mg/kg daily) for 4 d.The patient progressed well.To the best of our knowledge, this is the first case of small bowel perforation associated with eggs of S.japonicum.展开更多
The efficiency of electrochemical water splitting is extremely hampered by the sluggish oxygen evolution reaction(OER)occurred at the anode.Therefore,developing high-performance OER electrocatalysts is crucial for rea...The efficiency of electrochemical water splitting is extremely hampered by the sluggish oxygen evolution reaction(OER)occurred at the anode.Therefore,developing high-performance OER electrocatalysts is crucial for realizing the industrialized application of water splitting.Herein,a high-efficiency electrocatalyst of ruthenium-decorated nickel-iron hydroxide(10 Ru-NiFe LDH)supported on Ni foam is successfully synthesized for OER.Modifying NiFe LDH with ruthenium can optimize the electronic density to form high valences of metal sites,which is beneficial to promote its OER performance.Consequently,the 10 Ru-NiFe LDH only needs a low overpotential of 222 mV to achieve a current density of50 mA,cm^(-2),which exhibits fast OER kinetics with a small Tafel slope of 58 mV.dec^(-1).Moreover,this electrocatalyst shows high stability over 20 h at a high current density of 100 mA·cm^(-2)without obvious decay.The decent OER performances can be ascribed to the increased active sites and the synergistic electronic interactions among Ni,Fe and Ru.This work provides an effective approach for designing desirable electrocatalysts for OER.展开更多
According to the increasing requirement of the wind energy utilization and the dynamic stability in the variable speed variable pitch wind power generation system, a linear parameter varying (LPV) system model is es...According to the increasing requirement of the wind energy utilization and the dynamic stability in the variable speed variable pitch wind power generation system, a linear parameter varying (LPV) system model is established and a new adaptive robust guaranteed cost controller (AGCC) is proposed in this paper. First, the uncertain parameters of the system are estimated by using the adaptive method, then the estimated uncertain parameters and robust guaranteed cost control method are used to design a state feedback controller. The controller s feedback gain is obtained by solving a set of linear matrix inequality (LMI) constraints, such that the controller can meet a quadratic performance evaluation criterion. The simulation results show that we can realize the goal of maximum wind energy capture in low wind speed by the optimal torque control and constant power control in high wind speed by variable pitch control with good dynamic characteristics, robustness and the ability of suppressing disturbance.展开更多
Dear Editor, Cellular angiofibroma (CAF) is a rare benign mesenchymal lesion, which was first described in 1997 by Nucci et al.1 In previous reports, it has occurred mainly in the superficial soft tissue of the gen...Dear Editor, Cellular angiofibroma (CAF) is a rare benign mesenchymal lesion, which was first described in 1997 by Nucci et al.1 In previous reports, it has occurred mainly in the superficial soft tissue of the genital region, such as the scrotum, perineal, groin, vaginal introitus, and vulva,2 and rarely occurs in other locations. Here, we report a cellular angiofibroma in the epididymis; to our knowledge, such an epididymal location has not been reported in the literature so far. In this case, a 63-year-old male presented with a painless and well-circumscribed mass in the right epididymis.展开更多
基金Projects(51871250,51504106)supported by the National Natural Science Foundation of ChinaProject(SKL-SPM-201809)supported by the State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals,China+2 种基金Projects(502211852,502211906)supported by the Fundamental Research Funds for the Central Universities of Central South University,ChinaProject(SKYAM005-2016)supported by State Key Laboratory of Applied Microbiology Southern ChinaProjects(2015FB204,2016BA006,2017FA030)supported by the Yunnan Science and Technology Plan Project of China。
文摘The adsorption characteristics and mechanisms of modified sepiolite as an adsorbent to recover Pd(Ⅱ) from acidic solutions were studied. The Pd(Ⅱ) adsorption properties were analyzed through isotherm, kinetic and thermodynamic models. In addition, SEM-EDS, TEM and XPS were applied to investigating the Pd(Ⅱ) adsorption mechanisms onto modified sepiolite. The equilibrium data were well fitted to Langmuir isotherm model with maximum Pd(Ⅱ) adsorption capacity of 322.58 mg/g at 30 ℃. The kinetic data could be satisfactorily simulated by the pseudosecond order model, indicating that the rate-controlling step was chemical adsorption. 99% of Pd(Ⅱ) could be recovered using 1 g/L modified sepiolite when initial concentration of Pd(Ⅱ) was 100 mg/L. The results of reusability studies indicated the modified sepiolite had an acceptable stability and reusability. This study indicated that the modified sepiolite might be an efficient and cost-effective material for Pd(Ⅱ) recovery.
基金ACKN0WLEDGMENT This work was supported by the National Natural Science Foundation of China (No.90201013), the Natural Science Foundation of Fujian Province of China (No.A0510014), and the Science Foundation of the Educational Department of Fujian Province of China (No JB03151 and JB04246).
文摘Nd(DBM)3Phen-doped (DBM is dibenzoylmethane and Phen is phenanthroline) polymethyl methacrylate (PMMA) is prepared. Optical absorption, excitation and emission spectra were analyzed for Nd^3+ in Nd(DBM)3Phen-doped PMMA. Using the Judd-Ofelt theory, the absorption spectrum was analyzed. The Judd-Ofelt(J-O) intensity parameters of Nd(DBM)3Phen-doped polymethyl methacrylate were calculated to be Ω2 = 20.97 × 10^-20 cm^2, Ω4= 3.42 × 10^-20 cm^2, Ω6 = 2.90 × 10^-20 cm^2. The radiative lifetime (631 μs) of the excited 4F3/2 level is given. The stimulated emission cross-sections and the fluorescence branch ratios for the ^4F3/2 →^4Ij′ transitions are also evaluated. Analysis reveals that Nd(DBM)3Phen-doped PMMA is promising for application in polymer optical fibers and planar waveguides.
文摘A 67-year-old man from Jingzhou was admitted to the First Hospital Affiliated to Yangtze University in July 2013 with sudden onset of abdominal pain with dizziness for 12 h.The patient had sign of peritoneal irritation.Ultrasonography of the abdomen and pelvis showed hepatic fibrosis due to schistosomiasis.Computed tomography showed free gas in the peritoneal cavity.Plain abdominal radiography showed bilateral subdiaphragmatic accumulation of gas, perforation of the viscus, and radio-opacity in the left renal area.The patient underwent emergency exploratory laparotomy.At laparotomy, a moderate amount of muddy yellow pus was found in the intra-abdominal cavity.At the junction of the jejunum and ileum, about 250 cm from Treitz's ligament, there was an about 10-cm length of inflamed small bowel with perforation(3 mm in diameter) along the mesenteric border at the middle of the lesion.The patient underwent resection of the affected intestinal segment, along with end-to-end intestinal anastomosis.Histopathological examination revealed mucosal necrosis and hemorrhage with a large number of infiltrating eosinophils and neutrophils, and acute submucosal inflammation with a large number of infiltrating eosinophils and neutrophils associated with Schistosoma japonicum(S.japonicum) eggs.No intravascular adult parasite was found.Postoperatively, the patient was treated with praziquantel(30 mg/kg daily) for 4 d.The patient progressed well.To the best of our knowledge, this is the first case of small bowel perforation associated with eggs of S.japonicum.
基金financially supported by the National Natural Science Foundation of China (Nos.12074435, 51871250 and 52001335)the Science and Technology Innovation Program of Hunan Province (No.2021RC4001)the State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metal (No.SKL-SPM-202005)
文摘The efficiency of electrochemical water splitting is extremely hampered by the sluggish oxygen evolution reaction(OER)occurred at the anode.Therefore,developing high-performance OER electrocatalysts is crucial for realizing the industrialized application of water splitting.Herein,a high-efficiency electrocatalyst of ruthenium-decorated nickel-iron hydroxide(10 Ru-NiFe LDH)supported on Ni foam is successfully synthesized for OER.Modifying NiFe LDH with ruthenium can optimize the electronic density to form high valences of metal sites,which is beneficial to promote its OER performance.Consequently,the 10 Ru-NiFe LDH only needs a low overpotential of 222 mV to achieve a current density of50 mA,cm^(-2),which exhibits fast OER kinetics with a small Tafel slope of 58 mV.dec^(-1).Moreover,this electrocatalyst shows high stability over 20 h at a high current density of 100 mA·cm^(-2)without obvious decay.The decent OER performances can be ascribed to the increased active sites and the synergistic electronic interactions among Ni,Fe and Ru.This work provides an effective approach for designing desirable electrocatalysts for OER.
基金supported by Natural Science Foundation of Hebei Province(No. F2012203088)
文摘According to the increasing requirement of the wind energy utilization and the dynamic stability in the variable speed variable pitch wind power generation system, a linear parameter varying (LPV) system model is established and a new adaptive robust guaranteed cost controller (AGCC) is proposed in this paper. First, the uncertain parameters of the system are estimated by using the adaptive method, then the estimated uncertain parameters and robust guaranteed cost control method are used to design a state feedback controller. The controller s feedback gain is obtained by solving a set of linear matrix inequality (LMI) constraints, such that the controller can meet a quadratic performance evaluation criterion. The simulation results show that we can realize the goal of maximum wind energy capture in low wind speed by the optimal torque control and constant power control in high wind speed by variable pitch control with good dynamic characteristics, robustness and the ability of suppressing disturbance.
文摘Dear Editor, Cellular angiofibroma (CAF) is a rare benign mesenchymal lesion, which was first described in 1997 by Nucci et al.1 In previous reports, it has occurred mainly in the superficial soft tissue of the genital region, such as the scrotum, perineal, groin, vaginal introitus, and vulva,2 and rarely occurs in other locations. Here, we report a cellular angiofibroma in the epididymis; to our knowledge, such an epididymal location has not been reported in the literature so far. In this case, a 63-year-old male presented with a painless and well-circumscribed mass in the right epididymis.