Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2) reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.Howe...Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2) reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.However,photoreduction of CO_(2) by MHP remains a challenge because of the slow charge separation and transfer.Herein,a cobalt single-atom modified nitrogen-doped graphene(Co-NG)cocatalyst is prepared for enhanced photocatalytic CO_(2) reduction of bismuth-based MHP Cs_(3)Bi_(2)Br_(9).The optimal Cs_(3)Bi_(2)Br_(9)/Co-NG composite exhibits the CO production rate of 123.16μmol g^(-1)h^(-1),which is 17.3 times higher than that of Cs_(3)Bi_(2)Br_(9).Moreover,the Cs_(3)Bi_(2)Br_(9)/Co-NG composite photocatalyst exhibits nearly 100% CO selectivity as well as impressive long-term stability.Charge carrier dynamic characterizations such as Kelvin probe force microscopy(KPFM),single-particle PL microscope and transient absorption(TA)spectroscopy demonstrate the vital role of Co-NG cocatalyst in accelerating the transfer and separation of photogenerated charges and improving photocatalytic performance.The reaction mechanism has been demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy measurement.In addition,in situ X-ray photoelectron spectroscopy test and theoretical calculation reveal the reaction reactive sites and reaction energy barriers,demonstrating that the introduction of Co-NG promotes the formation of ^(*)COOH intermediate,providing sufficient evidence for the highly selective generation of CO.This work provides an effective single-atom-based cocatalyst modification strategy for photocatalytic CO_(2) reduction and is expected to shed light on other photocatalytic applications.展开更多
The electronic and magnetic properties of Ce doped SrMnO3 have been investigated us- ing the pseudo-potential plane wave method within the generalized gradient approximation method by first principles. The different M...The electronic and magnetic properties of Ce doped SrMnO3 have been investigated us- ing the pseudo-potential plane wave method within the generalized gradient approximation method by first principles. The different Mn-O bond lengths indicate that there is a strong Jahn-Teller distortion of the MnO6 octahedron, which associates with a structural phase transition from cubic symmetry （Pm3m） to tetragonal symmetry （I4/mcm）, and the Jahn- Teller ordering stabilizes a chain like （C-type） antiferromagnetie ground state. The electronic structures indicate that SrMnO3 and Sr1-xCexMnO3 （z=0.125 and 0.25） are semiconductor and metallic, respectively. The doping of SrMnO3 with cerium induces simultaneously a decrease in the electrical resistivity, which can be attributed to the formation of Mn3＋ as a result of charge compensation. The density of states and charge density map present that hybridization exists between some of O bands with those of Mn and Ce bands, the bonding between Sr and O is mainly ionic. Density of states and magnetic moment calculations show that the formal valence state of the Ce ion is trivalence.展开更多
Objective: To investigate effect of electroacupuncture (EA) on serum copper, zinc, calcium and magnesium levels in the rat models of depression. Methods: Forty healthy SD male rats were divided into a normal group, a ...Objective: To investigate effect of electroacupuncture (EA) on serum copper, zinc, calcium and magnesium levels in the rat models of depression. Methods: Forty healthy SD male rats were divided into a normal group, a model group, an EA group, and a maprotiline group, 10 in each with completely random. The depression models were prepared with isolated chronic unpredictable stress method in the latter three groups. EA was given at Baihui (GV 20), Yintang (EX-HN3), Fenglong (ST 40), and Taichong (LR 3) in the EA group from the second day of modeling, once every other day, 15 min each time. The maprotiline group was administered intragastrically suspension of maprotiline (10 mg/kg), once each day. After treatment for 3 weeks, serum copper and zinc levels were detected with atomic absorption method, and the serum calcium with Arsenazo Ⅲ method and magnesium with MTB method. Results: Compared with the normal group, the serum copper level (3.90±1.20mmol/L) significantly increased and the serum zinc level (2.08±0.44mmol/L) significantly decreased in the model group (P<0.05). Compared with the model group, the serum copper level (2.62±1.03mmol/L) significantly decreased, the serum zinc level (2.55±0.38mmol/L) significantly increased (P<0.05), but the serum calcium and magnesium levels did not significantly change in the EA group and the maprotiline group. Conclusion: EA can regulate the change of copper and zinc levels in the body induced by depression, which is possibly one of mechanisms of effectively improving depression symptoms.展开更多
Background Recently, it has been proposed that the autoantibodies against various cardiovascular receptors play a role in the pathogenesis of primary hypertension. In this study, we aimed to identify whether or not th...Background Recently, it has been proposed that the autoantibodies against various cardiovascular receptors play a role in the pathogenesis of primary hypertension. In this study, we aimed to identify whether or not there are autoantibodies against cardiovascular L-type Ca^2＋ channels in patients with primary hypertension. Methods A peptide corresponding to the sequence 2-16 of the alc-subunit of L-type Ca^2＋ channel was used as an antigen to screen the autoantibodies from 90 patients with primary hypertension and 45 healthy controls by an enzyme-linked immunosorbent assay （ELISA）. The clinical data of 90 hypertensive patients were compared between patients with and without these autoantibodies. Results Serum from 3 （6.7%） of the 45 healthy controls, 33 （36.7%） of 90 hypertensives showed positive responses in ELISA （P 〈0.01）. The prevalence of such autoantibodies in two subgroups of hypertensives with coronary heart disease （9/21, 57.14%, P 〈0.05） and left ventricular diastolic dysfunction （28/63, 44.4%, P 〈0.05） was higher than in those without the corresponding complications. And the patients with such autoantibodies had lower E/A than patients without such autoantibodies （0.803±0.191 vs 1.004±0.322, P=0.002）. Conclusion There are autoantibodies against vascular L-tyPe Ca^2＋ channels in patients with primary hvnertension.展开更多
文摘Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2) reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.However,photoreduction of CO_(2) by MHP remains a challenge because of the slow charge separation and transfer.Herein,a cobalt single-atom modified nitrogen-doped graphene(Co-NG)cocatalyst is prepared for enhanced photocatalytic CO_(2) reduction of bismuth-based MHP Cs_(3)Bi_(2)Br_(9).The optimal Cs_(3)Bi_(2)Br_(9)/Co-NG composite exhibits the CO production rate of 123.16μmol g^(-1)h^(-1),which is 17.3 times higher than that of Cs_(3)Bi_(2)Br_(9).Moreover,the Cs_(3)Bi_(2)Br_(9)/Co-NG composite photocatalyst exhibits nearly 100% CO selectivity as well as impressive long-term stability.Charge carrier dynamic characterizations such as Kelvin probe force microscopy(KPFM),single-particle PL microscope and transient absorption(TA)spectroscopy demonstrate the vital role of Co-NG cocatalyst in accelerating the transfer and separation of photogenerated charges and improving photocatalytic performance.The reaction mechanism has been demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy measurement.In addition,in situ X-ray photoelectron spectroscopy test and theoretical calculation reveal the reaction reactive sites and reaction energy barriers,demonstrating that the introduction of Co-NG promotes the formation of ^(*)COOH intermediate,providing sufficient evidence for the highly selective generation of CO.This work provides an effective single-atom-based cocatalyst modification strategy for photocatalytic CO_(2) reduction and is expected to shed light on other photocatalytic applications.
文摘The electronic and magnetic properties of Ce doped SrMnO3 have been investigated us- ing the pseudo-potential plane wave method within the generalized gradient approximation method by first principles. The different Mn-O bond lengths indicate that there is a strong Jahn-Teller distortion of the MnO6 octahedron, which associates with a structural phase transition from cubic symmetry （Pm3m） to tetragonal symmetry （I4/mcm）, and the Jahn- Teller ordering stabilizes a chain like （C-type） antiferromagnetie ground state. The electronic structures indicate that SrMnO3 and Sr1-xCexMnO3 （z=0.125 and 0.25） are semiconductor and metallic, respectively. The doping of SrMnO3 with cerium induces simultaneously a decrease in the electrical resistivity, which can be attributed to the formation of Mn3＋ as a result of charge compensation. The density of states and charge density map present that hybridization exists between some of O bands with those of Mn and Ce bands, the bonding between Sr and O is mainly ionic. Density of states and magnetic moment calculations show that the formal valence state of the Ce ion is trivalence.
基金New Century Excellent Talents in University of China (NCET-06-0879)National High Technology Research and Development Program ("863" Program) of China (2006AA03Z0449)National Basic Research Program ("973" Program) of China (2007CB613805)
基金supported by the International Classical CulturalAssociation (No. XDHT2009023A)
文摘Objective: To investigate effect of electroacupuncture (EA) on serum copper, zinc, calcium and magnesium levels in the rat models of depression. Methods: Forty healthy SD male rats were divided into a normal group, a model group, an EA group, and a maprotiline group, 10 in each with completely random. The depression models were prepared with isolated chronic unpredictable stress method in the latter three groups. EA was given at Baihui (GV 20), Yintang (EX-HN3), Fenglong (ST 40), and Taichong (LR 3) in the EA group from the second day of modeling, once every other day, 15 min each time. The maprotiline group was administered intragastrically suspension of maprotiline (10 mg/kg), once each day. After treatment for 3 weeks, serum copper and zinc levels were detected with atomic absorption method, and the serum calcium with Arsenazo Ⅲ method and magnesium with MTB method. Results: Compared with the normal group, the serum copper level (3.90±1.20mmol/L) significantly increased and the serum zinc level (2.08±0.44mmol/L) significantly decreased in the model group (P<0.05). Compared with the model group, the serum copper level (2.62±1.03mmol/L) significantly decreased, the serum zinc level (2.55±0.38mmol/L) significantly increased (P<0.05), but the serum calcium and magnesium levels did not significantly change in the EA group and the maprotiline group. Conclusion: EA can regulate the change of copper and zinc levels in the body induced by depression, which is possibly one of mechanisms of effectively improving depression symptoms.
基金This study was supported by a grant from the National Natural Science Foundation of China （No. C03030201）.
文摘Background Recently, it has been proposed that the autoantibodies against various cardiovascular receptors play a role in the pathogenesis of primary hypertension. In this study, we aimed to identify whether or not there are autoantibodies against cardiovascular L-type Ca^2＋ channels in patients with primary hypertension. Methods A peptide corresponding to the sequence 2-16 of the alc-subunit of L-type Ca^2＋ channel was used as an antigen to screen the autoantibodies from 90 patients with primary hypertension and 45 healthy controls by an enzyme-linked immunosorbent assay （ELISA）. The clinical data of 90 hypertensive patients were compared between patients with and without these autoantibodies. Results Serum from 3 （6.7%） of the 45 healthy controls, 33 （36.7%） of 90 hypertensives showed positive responses in ELISA （P 〈0.01）. The prevalence of such autoantibodies in two subgroups of hypertensives with coronary heart disease （9/21, 57.14%, P 〈0.05） and left ventricular diastolic dysfunction （28/63, 44.4%, P 〈0.05） was higher than in those without the corresponding complications. And the patients with such autoantibodies had lower E/A than patients without such autoantibodies （0.803±0.191 vs 1.004±0.322, P=0.002）. Conclusion There are autoantibodies against vascular L-tyPe Ca^2＋ channels in patients with primary hvnertension.
