BACKGROUND： Ultraviolet blood irradiation and oxygenation （UBIO） has obtained better clinical effect in treating acute cerebral infarction, but the mechanism underlying this effect remains unclear. OBJECTIVE： To o...BACKGROUND： Ultraviolet blood irradiation and oxygenation （UBIO） has obtained better clinical effect in treating acute cerebral infarction, but the mechanism underlying this effect remains unclear. OBJECTIVE： To observe the effect of UBIO on the nerve function and activities of K^＋-Na^＋-ATPase and Ca2^＋-Mg2^＋-ATPase activities on the red blood cell （RBC） membrane of patients with acute cerebral infarction. DESIGN： A randomized and controlled study.SETTING： Department of Neurology, Xiangfan Central Hospital.PARTICIPANTS： From January 2000 to December 2001, excluding those above 70 years old, 58 cases of 700 patients with acute cerebral infarction admitted in the Department of Neurology, Xiangfan Central Hospital, were recruited and divided into two groups according to the random number table： UBIO treated group （n=28）, including 17 males and 11 females, aged 40-68 years; and control group （n=30）, including 20 males and 10 females, aged 44-69 years. All the patients agreed to participate in the therapeutic program and detected items. The general informations were comparable without obvious differences between the two groups （P 〉 0.05）.METHODS： ① The patients in both groups received routine treatments, besides, those in the UBIO treated group were given UBIO treatment by using the XL-200 type therapeutic apparatus produced in Shijiazhuang, whose ultraviolet wave was set at 253.7 nm with the energy density of 0.568 J/m^2 per second, UBIO treatment started from the second day after admission, once every other day, with a single course consisting of 5-7 treatments. ② In the UBIO treated group, the venous blood was sampled before and after the first, third and the completion of the treatment course respectively, the venous blood was taken at each corresponding time point in the control group. After centrifugation of the blood at 10 000 rounds per minute, the RBC membrane was separated and then the activities of K^＋-Na^＋-ATPase and Ca2^＋-Mg2^＋-ATPase were detected by means of phosphorus determination.③ The nerve function was scored before and after treatment in both groups with European stroke scale, which included 13 items, the total score was 0-100 points, the higher the score, the better the nerve function. MAIN OUTCOME MEASURES ：①Score of European stroke scale before and after treatment in both groups.② Comparison of the activities of K^＋-Na^＋-ATPase and Ca2^＋-Mg2^＋-ATPase on RBC membrane between the two groups before treatment and after the first, third and the completion of the treatment. RESULTS： All the 58 patients with cerebral infarction were involved in the analysis of results.① The score of European stroke scale had no obvious difference between the two groups [（49.31±11.48）, （50.58±12.63）, P 〉 0.05], and it was obviously higher in the UBIO treated group than in the control group after treatment [84.66±13.75）, （77.05±11.17）, P 〈 0.05].②The activity of K^＋-Na^＋-ATPase on RBC membrane in the UBIO treated group was significantly increased after the first and third treatment as compared with before treatment [（31.56±19.25）, （27.64±15.83）, （17.67±13.83）, P 〈 0.01], it was still higher after the completion of the treatment than before treatment without obvious difference [（20.86±14.53）, P 〉 0.05]. After the first and third treatment, it was obviously higher in the UBIO treated group than in the control group [19.31±11.88）, （17.44±10.42）, P 〈 0.01]. ③ In the UBIO treated group, Ca2^＋-Mg2^＋-ATPase activity on RBC membrane significantly increased after the first treatment and remained higher than the pre-treatment level throughout the treatment [（27.49±14.72）, （17.41±4.82）, P 〈 0.01]. The activity of Ca2^＋-Mg2^＋-ATPase on RBC membrane was markedly higher in the UBIO treated group than in the control group after after the first, third and the completion of treatment respectively [（24.83±12.88）, （17.70±5.69）; （28.08±13.44）, （16.32±5.29）; （17.42±6.04）, P〈 0.05-0.01]. CONCLUSION： The effect of UBIO treatment against acute cerebral infarction may be mediated by the increased K^＋-Na^＋ ATPase and Ca2^＋-Mg2^＋-ATPase activities on RBC membrane, which enhances the RBC transformation ability so as to lower RBC aggregation and correct high blood viscosity.展开更多
Lithium-rich manganese-based oxide(LRMO)cathode has emerged as a particularly promising candidate for achieving high energy densities in lithium-ion batteries due to its capability to access anion redox reactions at h...Lithium-rich manganese-based oxide(LRMO)cathode has emerged as a particularly promising candidate for achieving high energy densities in lithium-ion batteries due to its capability to access anion redox reactions at high voltage.The successful implementation of LRMO in energy storage systems is contingent upon the enhancement of their rate capabilities.However,the underlying relationship between high-rate cycling and electrode degradation for LRMO,particularly concerning structural evolution,still remains unclear.Benefiting from the high time resolution abilities of liquid-metal-jet operando twodimensional X-ray diffraction,it is observed that the Li_(2)MnO_(3)phase in LRMO is gradually activated accompanied by the emergence of oxygen vacancies during cycling at 1 C(1 C=250 mA/g).Consequently,the crystal lattice flexibility of LRMO is systematically enhanced,thereby preventing the collapse of the bulk structure.While,continuous release of oxygen during extended cycling results in deteriorations of the self-adjusting damping effect of the structure,ultimately leading to a decline in capacity.The findings of this study not only contribute to a more profound understanding of the structural changes of LRMOs at high rates,but also provide novel perspectives for the rational design of LRMOs with superior rate performances.展开更多
Transparent conductive cadmium indium oxide films (CdIn2O4) were prepared by r.f. reactive sputtering from Cd-In alloy targets under an Ar-O2 atmosphere. Electrical conductivity of the order of 105Ω-1.m-1 and the opt...Transparent conductive cadmium indium oxide films (CdIn2O4) were prepared by r.f. reactive sputtering from Cd-In alloy targets under an Ar-O2 atmosphere. Electrical conductivity of the order of 105Ω-1.m-1 and the optical transmission as high as 94% are easily attained by postdeposition annealing treatment. The effects of oxygen concentration in the reactive gas mixture and post-deposition annealing treatment on the optical transmittance as well as optical parameters, such as refractive index (n), extinction coefficient (k), real part (ε') and imaginary part (ε') of the dielectric constant, were studied in the visible and near-infrared region. The highfrequency dielectric constant ε∞ the plasma frequency ωP, and the conduction band effective mass mc of different samples were also investigated展开更多
The effect of oxygen partial pressure （Po2） during the channel layer deposition on bias stability of amorphous indium-gallium-zinc oxide （a-IGZO） thin film transistors （TFTs） is investigated. As Po2 increases fr...The effect of oxygen partial pressure （Po2） during the channel layer deposition on bias stability of amorphous indium-gallium-zinc oxide （a-IGZO） thin film transistors （TFTs） is investigated. As Po2 increases from 10% to 30%, it is found that the device shows enhanced bias stress stability with significantly reduced threshold voltage drift under positive gate bias stress. Based on the x-ray photoelectron spectroscopy measurement, the concentration of oxygen vacancies （Or） within the a-IGZO layer is suppressed by increasing Po2. Meanwhile, the low-frequency noise analysis indicates that the average trap density near the channel/dielectric interface continuously drops with increasing Po2. Therefore, the improved interface quality with increasing Po2 during the channel layer deposition can be attributed to the reduction of interface Ov-related defects, which agrees with the enhanced bias stress stability of the a-IGZO TFTs.展开更多
Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- ...Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- bis（phenyl）-10-（pentafluorophenyl）corrole Mn（V）-oxo（F_5CMn（V）-oxo） and 5,10,15-tris（phenyl）corrole Mn（V）-oxo（F_0CMn（V）-oxo） with a series of alkene substrates in different solvents were determined by UV-vis spectroscopy.The results indicated that the oxygen atom transfer pathway between Mn（V）-oxo corrole and alkene is solvent-dependent.展开更多
Higher-s dielectric LaLuO3, deposited by molecular beam deposition, with TiN as gate stack is integrated into high-mobility Si/SiGe/SOI quantum-well p-type metal-oxide-semiconduetor field effect transistors. Threshold...Higher-s dielectric LaLuO3, deposited by molecular beam deposition, with TiN as gate stack is integrated into high-mobility Si/SiGe/SOI quantum-well p-type metal-oxide-semiconduetor field effect transistors. Threshold voltage shift and capacitance equivalent thickness shrink are observed, resulting from oxygen scavenging effect in LaLuO3 with ti-rich TiN after high temperature annealing. The mechanism of oxygen scavenging and its potential for resistive memory applications are analyzed and discussed.展开更多
The effective segregation coefficient K-e of oxygen in terbium metal was deduced from a comparison of the theoretical curves with the concentration distributions found experimentally after a floating zone refining tre...The effective segregation coefficient K-e of oxygen in terbium metal was deduced from a comparison of the theoretical curves with the concentration distributions found experimentally after a floating zone refining treatment. Thp result shows that K-e is equal to 1.2 which is an important parameter for floating zone refining terbium.展开更多
Objective To evaluate the effects of hyperbaric oxygen therapy (HBOT) on Glasgow Coma Scale (GCC) after traumatic brain injury (TBI) in patients. Methods One hundred and thirty-eight patients with traumatic brain inju...Objective To evaluate the effects of hyperbaric oxygen therapy (HBOT) on Glasgow Coma Scale (GCC) after traumatic brain injury (TBI) in patients. Methods One hundred and thirty-eight patients with traumatic brain injury were treated by routine therapy combined with HBOT and 29 patients by routine therapy.展开更多
Objective To investigatewhether antioxidants inhibit adhesion of leukocytes to endothelium and furthermore, whether all antioxidants regulate NF-KB activation through a redox sensitive mechanism. Methods The effect of...Objective To investigatewhether antioxidants inhibit adhesion of leukocytes to endothelium and furthermore, whether all antioxidants regulate NF-KB activation through a redox sensitive mechanism. Methods The effect of the antioxidative substances pyrrolidin dithiocarbamat (PDTC), dichloroisocumarin (DCI), chrysin and probucol on the endothelial leukocyte adhesion were examined under near physiological flow conditions. The antioxidative activity of antioxidants was measured in a DCF fluorescence assay with flow cytometry. The activation of NF-kB in endothelial cells was investigated in a gel shift assay. Results PDTC and probucol did not show an inhibitory effect to the formation of intracellular H2O2 in TNFa activated human vascular endothelial cells (HUVEC) . Chrysin showed a moderate effect. DCI showed a strong antioxidative effect. In contrast, PDTC and chrysin inhibited the adhesion of HL 60 cells to TNFa-stimulated HUVEC. DCI and probucol did not have influence on the adhesion within the area of the examined shear stresses. Only PDTC inhibited the TNFa-induced activation of NF-KB in endothelial cells. Conclusion The inhibition of the endothelial leukocyte adhesion by antioxidative substances is not to be explained by its antioxidative characteristics only. The inhibitory effect of PDTC on NF-KB activation was probably not related to its antioxidative properties. Endothelial cell Antioxidants NF-kappa-B展开更多
A multi-dimensional conductive heterojunction structure,composited by TiO2,SnO2,and Ti3C2TX MXene,is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells.Base...A multi-dimensional conductive heterojunction structure,composited by TiO2,SnO2,and Ti3C2TX MXene,is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells.Based on an oxygen vacancy scramble effect,the zero-dimensional anatase TiO2 quantum dots,surrounding on two-dimensional conductive Ti3C2TX sheets,are in situ rooted on three-dimensional SnO2 nanoparticles,constructing nanoscale TiO2/SnO2 heterojunctions.The fabrication is implemented in a controlled lowtemperature anneal method in air and then in N2 atmospheres.With the optimal MXene content,the optical property,the crystallinity of perovskite layer,and internal interfaces are all facilitated,contributing more amount of carrier with effective and rapid transferring in device.The champion power conversion efficiency of resultant perovskite solar cells achieves 19.14%,yet that of counterpart is just 16.83%.In addition,it can also maintain almost 85%of its initial performance for more than 45 days in 30–40%humidity air;comparatively,the counterpart declines to just below 75%of its initial performance.展开更多
Atmospheric-pressure(AP)plasma etching provides an alternative method for mechanical grinding to realize wafer thinning of Si wafer.It can avoid the damages and micro-cracks that would be introduced by mechanical stre...Atmospheric-pressure(AP)plasma etching provides an alternative method for mechanical grinding to realize wafer thinning of Si wafer.It can avoid the damages and micro-cracks that would be introduced by mechanical stress during the grinding process.In this study,the material removal characteristics of Si(100)wafer processed by linear field AP plasma generated using carbon tetrafluoride(CF4)as the reactive source were analyzed.This linear field plasma etching tool has a typical removal profile and the depth removal rate that can reach up to 1.082μm/min.The effect ofO2 concentration on the removal ratewas discussed and the surfacemorphology during the process was characterized using scanning electron microscopy.It is shown that the subsurface damage layer was gradually removed during the etching process and the surface was observed to be smoothened with the increase of the etching depth.This present work contributes a basic understanding of the linear field AP plasma etching performance with different gas composition and the typical characteristics would be further applied to damage-free precision removal of Si.展开更多
In recent decade, Au nanoclusters of atomic precision （AunLm, where L= organic ligand： thiolate andphosphine） have been shown as a new promising nanogold catalyst. The well-defined AunLm catalystspossess unique ele...In recent decade, Au nanoclusters of atomic precision （AunLm, where L= organic ligand： thiolate andphosphine） have been shown as a new promising nanogold catalyst. The well-defined AunLm catalystspossess unique electronic properties and frameworks, providing an excellent opportunity to correlate theintrinsic catalytic behavior with the cluster＇s framework as well as to study the catalytic mechanismsover gold nanoclusters. In this review, we only demonstrate the important roles of the gold nanoclustersin the oxygen activation （e.g., 302 to 102） and their selective oxidations in the presence of oxygen （e.g., COto C02, sulfides to sulfoxides, alcohol to aldehyde, styrene to styrene epoxide, amines to imines, andglucose to gluconic acid）. The size-specificity （Au25 （1.3 nm）, Au38 （].5 nm）, Au144 （1.9 nm）, etc.）, ligandengineering （e.g., aromatic vs aliphatic）, and doping effects （e.g., copper, silver, palladium, and platinum）are discussed in details. Finally, the proposed reactions＇ mechanism and the relationships of clusters＇structure and activity at the atomic level also are presented.展开更多
The regulation of electron transfer is crucial for enhancing the catalytic efficiency of catalysts.Currently,CO selective reduction of NO_(x)(CO-SCR)catalysts with surface synergistic oxygen vacancies(SSOVs)or alloyed...The regulation of electron transfer is crucial for enhancing the catalytic efficiency of catalysts.Currently,CO selective reduction of NO_(x)(CO-SCR)catalysts with surface synergistic oxygen vacancies(SSOVs)or alloyed components exhibit superior performance but face challenges of reduced activity and stability in oxygen-rich environments.Here,we demonstrate a strategy that combines PtCo alloys(0.01%Pt;0.04%Co)with SSOVs in cerium zirconium oxide solid solution to interactively modulate the electronic structure,resulting in a significant enhancement of both the activity and stability of the catalyst under oxygenrich conditions.This catalyst achieved over 85%NO conversion at 300℃ and 5%O_(2),while maintaining approximately 100%N2 selectivity during 20 h-stability testing,surpassing the performance of the monometallic catalysts.This enhancement arises from the synergistic electronic effects of alloying and SSOVs,which generate negatively charged Pt that facilitates NO adsorption and dissociation,while concurrently producing electron-deficient SSOVs that weaken O_(2) chemisorption and promote the formation of moderate reactive oxygen species.Moreover,the preferential adsorption of CO on Co sites alleviates competitive adsorption.展开更多
We studied the effect of oxygen on the growth quality of diamond epitaxial layers. After oxygen is added during the growth of the diamond epitaxial layer, as the thickness of the epitaxial layer increases, the full wi...We studied the effect of oxygen on the growth quality of diamond epitaxial layers. After oxygen is added during the growth of the diamond epitaxial layer, as the thickness of the epitaxial layer increases, the full width at half maximum of the rocking curve of the(004) plane of diamond epitaxial layer increases continuously, and, in addition, the intensities of both the Raman peaks and the free exciton emission peaks of the diamond epitaxial layer decrease continuously. These experimental results demonstrate that as the thickness of the diamond epitaxial layer increases, the quality of the diamond epitaxial layer degrades. The strong etching effect of the OH radical groups in the plasma on the diamond epilayers leads to the degradation of their crystallinity.展开更多
The oxygen reduction kinetics on polycobaltprotoporphyrin(PCoPP)film has been examined with the rotating disc electrode technique in O_2-saturated solution of various pH.PCoPP film promotes the oxygen reduction proces...The oxygen reduction kinetics on polycobaltprotoporphyrin(PCoPP)film has been examined with the rotating disc electrode technique in O_2-saturated solution of various pH.PCoPP film promotes the oxygen reduction process via two electrons to produce peroxide over wide pH range. When pH value of solution decreases,catalytic activity of PCoPP film increases.Possible catalytic mechanisms have been proposed for oxygen reduction.展开更多
We have successfully synthesized Sr 2 CuO3+δ single crystals under high pressure and high temperature for the first time. The structure analysis show that this material crystallizes into tetragonal structure isostruc...We have successfully synthesized Sr 2 CuO3+δ single crystals under high pressure and high temperature for the first time. The structure analysis show that this material crystallizes into tetragonal structure isostructural La 2 CuO4 with single CuO 2 plane. The magnetic susceptibility as well as resistance measurements indicates that the bulk superconductivity with the critical transition temperature 37 K is achieved in the crystal.展开更多
The oxygen evolution reaction(OER)and electrochemical ozone production(EOP)attracted considerable attention due to their wide applications in electrocatalysis,but the detailed reaction mechanism of product formation a...The oxygen evolution reaction(OER)and electrochemical ozone production(EOP)attracted considerable attention due to their wide applications in electrocatalysis,but the detailed reaction mechanism of product formation as well as the voltage effect on O_(2)/O_(3)formation still remains unclear.In this work,density functional theory calculations were used to systematically investigate the possible reaction mechanisms of OER and EOP on the PbO_(2)(110)surface,with the possible reaction network involving surface lattice oxygen atoms(LOM)proposed.The results show that the LOM-2 reaction pathway involving two surface lattice oxygen atoms(Olatt)and one oxygen atom from H_(2)O was the most thermodynamically reactive.Different potential determining step(PDS)was obtained depending on the multiple reaction pathway,and the results show that the facile diffusion of Olattwould proceed the LOM pathway and promote the formation of surface oxygen vacancies(O_(vac1)/O_(vac2)).Furthermore,O_(vac1)/O_(vac2)formation on the surface would trigger further reactions of H_(2)O adsorption and splitting,which refilled the oxygen vacancy and ensured the considerable stability of the PbO_(2)(110)surface.Multiple H_(2)O dissociation pathways were proposed on PbO_(2)(110)with oxygen vacancy sites:the acid-base interaction mechanism and the vacancy fulfilling mechanism.展开更多
To commercialize fuel cells and metal-air batteries, cost-effective, highly active catalysts for the oxygen reduction reaction （ORR） must be developed. Herein, we describe the development of low-cost, heteroatom （N...To commercialize fuel cells and metal-air batteries, cost-effective, highly active catalysts for the oxygen reduction reaction （ORR） must be developed. Herein, we describe the development of low-cost, heteroatom （N, P, Fe） ternary-doped, porous carbons （HDPC）. These materials are prepared by one-step pyrolysis of natural tea leaves treated with an iron salt, without any chemical and physical activation. The natural structure of the tea leaves provide a 3D hierarchical porous structure after carbonization. Moreover, heteroatom containing organic compounds in tea leaves act as precursors to functionalize the resultant carbon frameworks. In addition, we found that the polyphenols present in tea leaves act as ligands, reacting with Fe ions to form coordination compounds; these complexes acted as the precursors for Fe and N active sites. After pyrolysis, the as-prepared HDPC electrocatalysts, especially HDPC-800 （pyrolyzed at 800℃）, had more positive onsets, half-wave potentials, and higher catalytic activities for the ORR, which proceeds via a direct four-electron reaction pathway in alkaline media, similar to commercial Pt/C catalysts. Furthermore, HDPC-X also showed enhanced durability and better tolerance to methanol crossover and CO poisoning effects in comparison to commercial Pt/C, making them promising alternatives for state-of-the-art ORR electrocatalysts for electrochemical energy conversion. The method used here provides valuable guidelines for the design of high-performance ORR electrocatalysts from natural sources at the industrial scale.展开更多
文摘BACKGROUND： Ultraviolet blood irradiation and oxygenation （UBIO） has obtained better clinical effect in treating acute cerebral infarction, but the mechanism underlying this effect remains unclear. OBJECTIVE： To observe the effect of UBIO on the nerve function and activities of K^＋-Na^＋-ATPase and Ca2^＋-Mg2^＋-ATPase activities on the red blood cell （RBC） membrane of patients with acute cerebral infarction. DESIGN： A randomized and controlled study.SETTING： Department of Neurology, Xiangfan Central Hospital.PARTICIPANTS： From January 2000 to December 2001, excluding those above 70 years old, 58 cases of 700 patients with acute cerebral infarction admitted in the Department of Neurology, Xiangfan Central Hospital, were recruited and divided into two groups according to the random number table： UBIO treated group （n=28）, including 17 males and 11 females, aged 40-68 years; and control group （n=30）, including 20 males and 10 females, aged 44-69 years. All the patients agreed to participate in the therapeutic program and detected items. The general informations were comparable without obvious differences between the two groups （P 〉 0.05）.METHODS： ① The patients in both groups received routine treatments, besides, those in the UBIO treated group were given UBIO treatment by using the XL-200 type therapeutic apparatus produced in Shijiazhuang, whose ultraviolet wave was set at 253.7 nm with the energy density of 0.568 J/m^2 per second, UBIO treatment started from the second day after admission, once every other day, with a single course consisting of 5-7 treatments. ② In the UBIO treated group, the venous blood was sampled before and after the first, third and the completion of the treatment course respectively, the venous blood was taken at each corresponding time point in the control group. After centrifugation of the blood at 10 000 rounds per minute, the RBC membrane was separated and then the activities of K^＋-Na^＋-ATPase and Ca2^＋-Mg2^＋-ATPase were detected by means of phosphorus determination.③ The nerve function was scored before and after treatment in both groups with European stroke scale, which included 13 items, the total score was 0-100 points, the higher the score, the better the nerve function. MAIN OUTCOME MEASURES ：①Score of European stroke scale before and after treatment in both groups.② Comparison of the activities of K^＋-Na^＋-ATPase and Ca2^＋-Mg2^＋-ATPase on RBC membrane between the two groups before treatment and after the first, third and the completion of the treatment. RESULTS： All the 58 patients with cerebral infarction were involved in the analysis of results.① The score of European stroke scale had no obvious difference between the two groups [（49.31±11.48）, （50.58±12.63）, P 〉 0.05], and it was obviously higher in the UBIO treated group than in the control group after treatment [84.66±13.75）, （77.05±11.17）, P 〈 0.05].②The activity of K^＋-Na^＋-ATPase on RBC membrane in the UBIO treated group was significantly increased after the first and third treatment as compared with before treatment [（31.56±19.25）, （27.64±15.83）, （17.67±13.83）, P 〈 0.01], it was still higher after the completion of the treatment than before treatment without obvious difference [（20.86±14.53）, P 〉 0.05]. After the first and third treatment, it was obviously higher in the UBIO treated group than in the control group [19.31±11.88）, （17.44±10.42）, P 〈 0.01]. ③ In the UBIO treated group, Ca2^＋-Mg2^＋-ATPase activity on RBC membrane significantly increased after the first treatment and remained higher than the pre-treatment level throughout the treatment [（27.49±14.72）, （17.41±4.82）, P 〈 0.01]. The activity of Ca2^＋-Mg2^＋-ATPase on RBC membrane was markedly higher in the UBIO treated group than in the control group after after the first, third and the completion of treatment respectively [（24.83±12.88）, （17.70±5.69）; （28.08±13.44）, （16.32±5.29）; （17.42±6.04）, P〈 0.05-0.01]. CONCLUSION： The effect of UBIO treatment against acute cerebral infarction may be mediated by the increased K^＋-Na^＋ ATPase and Ca2^＋-Mg2^＋-ATPase activities on RBC membrane, which enhances the RBC transformation ability so as to lower RBC aggregation and correct high blood viscosity.
基金financial supports from the National Natural Science Foundation of China(52372211,52371225 and 92472115)the Guangdong Province Major Talent Introducing Program(2021QN020687)+1 种基金the Shenzhen Basic Research Foundation(JCYJ20230807112503007)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2020A1515110176)。
文摘Lithium-rich manganese-based oxide(LRMO)cathode has emerged as a particularly promising candidate for achieving high energy densities in lithium-ion batteries due to its capability to access anion redox reactions at high voltage.The successful implementation of LRMO in energy storage systems is contingent upon the enhancement of their rate capabilities.However,the underlying relationship between high-rate cycling and electrode degradation for LRMO,particularly concerning structural evolution,still remains unclear.Benefiting from the high time resolution abilities of liquid-metal-jet operando twodimensional X-ray diffraction,it is observed that the Li_(2)MnO_(3)phase in LRMO is gradually activated accompanied by the emergence of oxygen vacancies during cycling at 1 C(1 C=250 mA/g).Consequently,the crystal lattice flexibility of LRMO is systematically enhanced,thereby preventing the collapse of the bulk structure.While,continuous release of oxygen during extended cycling results in deteriorations of the self-adjusting damping effect of the structure,ultimately leading to a decline in capacity.The findings of this study not only contribute to a more profound understanding of the structural changes of LRMOs at high rates,but also provide novel perspectives for the rational design of LRMOs with superior rate performances.
文摘Transparent conductive cadmium indium oxide films (CdIn2O4) were prepared by r.f. reactive sputtering from Cd-In alloy targets under an Ar-O2 atmosphere. Electrical conductivity of the order of 105Ω-1.m-1 and the optical transmission as high as 94% are easily attained by postdeposition annealing treatment. The effects of oxygen concentration in the reactive gas mixture and post-deposition annealing treatment on the optical transmittance as well as optical parameters, such as refractive index (n), extinction coefficient (k), real part (ε') and imaginary part (ε') of the dielectric constant, were studied in the visible and near-infrared region. The highfrequency dielectric constant ε∞ the plasma frequency ωP, and the conduction band effective mass mc of different samples were also investigated
基金Supported by the National Basic Research Program of China under Grant Nos 2010CB327504,2011CB922100 and2011CB301900the National Natural Science Foundation of China under Grant Nos 11104130 and 61322112+2 种基金the Natural Science Foundation of Jiangsu Province under Grant Nos BK2011556 and BK2011050the Priority Academic Program Development of Jiangsu Higher Education Institutionsand the NUPTSF Grant Nos NY213069 and NY214028
文摘The effect of oxygen partial pressure （Po2） during the channel layer deposition on bias stability of amorphous indium-gallium-zinc oxide （a-IGZO） thin film transistors （TFTs） is investigated. As Po2 increases from 10% to 30%, it is found that the device shows enhanced bias stress stability with significantly reduced threshold voltage drift under positive gate bias stress. Based on the x-ray photoelectron spectroscopy measurement, the concentration of oxygen vacancies （Or） within the a-IGZO layer is suppressed by increasing Po2. Meanwhile, the low-frequency noise analysis indicates that the average trap density near the channel/dielectric interface continuously drops with increasing Po2. Therefore, the improved interface quality with increasing Po2 during the channel layer deposition can be attributed to the reduction of interface Ov-related defects, which agrees with the enhanced bias stress stability of the a-IGZO TFTs.
基金The financial support from the National Natural Science Foundation of China(Nos.20971046 and 21171057)
文摘Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- bis（phenyl）-10-（pentafluorophenyl）corrole Mn（V）-oxo（F_5CMn（V）-oxo） and 5,10,15-tris（phenyl）corrole Mn（V）-oxo（F_0CMn（V）-oxo） with a series of alkene substrates in different solvents were determined by UV-vis spectroscopy.The results indicated that the oxygen atom transfer pathway between Mn（V）-oxo corrole and alkene is solvent-dependent.
基金Supported by the National Natural Science Foundation of China under Grant No 61306126
文摘Higher-s dielectric LaLuO3, deposited by molecular beam deposition, with TiN as gate stack is integrated into high-mobility Si/SiGe/SOI quantum-well p-type metal-oxide-semiconduetor field effect transistors. Threshold voltage shift and capacitance equivalent thickness shrink are observed, resulting from oxygen scavenging effect in LaLuO3 with ti-rich TiN after high temperature annealing. The mechanism of oxygen scavenging and its potential for resistive memory applications are analyzed and discussed.
文摘The effective segregation coefficient K-e of oxygen in terbium metal was deduced from a comparison of the theoretical curves with the concentration distributions found experimentally after a floating zone refining treatment. Thp result shows that K-e is equal to 1.2 which is an important parameter for floating zone refining terbium.
文摘Objective To evaluate the effects of hyperbaric oxygen therapy (HBOT) on Glasgow Coma Scale (GCC) after traumatic brain injury (TBI) in patients. Methods One hundred and thirty-eight patients with traumatic brain injury were treated by routine therapy combined with HBOT and 29 patients by routine therapy.
文摘Objective To investigatewhether antioxidants inhibit adhesion of leukocytes to endothelium and furthermore, whether all antioxidants regulate NF-KB activation through a redox sensitive mechanism. Methods The effect of the antioxidative substances pyrrolidin dithiocarbamat (PDTC), dichloroisocumarin (DCI), chrysin and probucol on the endothelial leukocyte adhesion were examined under near physiological flow conditions. The antioxidative activity of antioxidants was measured in a DCF fluorescence assay with flow cytometry. The activation of NF-kB in endothelial cells was investigated in a gel shift assay. Results PDTC and probucol did not show an inhibitory effect to the formation of intracellular H2O2 in TNFa activated human vascular endothelial cells (HUVEC) . Chrysin showed a moderate effect. DCI showed a strong antioxidative effect. In contrast, PDTC and chrysin inhibited the adhesion of HL 60 cells to TNFa-stimulated HUVEC. DCI and probucol did not have influence on the adhesion within the area of the examined shear stresses. Only PDTC inhibited the TNFa-induced activation of NF-KB in endothelial cells. Conclusion The inhibition of the endothelial leukocyte adhesion by antioxidative substances is not to be explained by its antioxidative characteristics only. The inhibitory effect of PDTC on NF-KB activation was probably not related to its antioxidative properties. Endothelial cell Antioxidants NF-kappa-B
基金supported by the Science & Technology Project of Anhui Province (16030701091)the Natural Science Research Project of Anhui Provincial Education Department (KJ2019A0030)+2 种基金the Support Project of Outstanding Young Talents in Anhui Provincial Universities (gxyqZD2018006)the National Natural Science Foundation of China(11704002, 31701323)the Anhui Provincial Natural Science Foundation (1908085QF251,1808085MF185)
文摘A multi-dimensional conductive heterojunction structure,composited by TiO2,SnO2,and Ti3C2TX MXene,is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells.Based on an oxygen vacancy scramble effect,the zero-dimensional anatase TiO2 quantum dots,surrounding on two-dimensional conductive Ti3C2TX sheets,are in situ rooted on three-dimensional SnO2 nanoparticles,constructing nanoscale TiO2/SnO2 heterojunctions.The fabrication is implemented in a controlled lowtemperature anneal method in air and then in N2 atmospheres.With the optimal MXene content,the optical property,the crystallinity of perovskite layer,and internal interfaces are all facilitated,contributing more amount of carrier with effective and rapid transferring in device.The champion power conversion efficiency of resultant perovskite solar cells achieves 19.14%,yet that of counterpart is just 16.83%.In addition,it can also maintain almost 85%of its initial performance for more than 45 days in 30–40%humidity air;comparatively,the counterpart declines to just below 75%of its initial performance.
文摘Atmospheric-pressure(AP)plasma etching provides an alternative method for mechanical grinding to realize wafer thinning of Si wafer.It can avoid the damages and micro-cracks that would be introduced by mechanical stress during the grinding process.In this study,the material removal characteristics of Si(100)wafer processed by linear field AP plasma generated using carbon tetrafluoride(CF4)as the reactive source were analyzed.This linear field plasma etching tool has a typical removal profile and the depth removal rate that can reach up to 1.082μm/min.The effect ofO2 concentration on the removal ratewas discussed and the surfacemorphology during the process was characterized using scanning electron microscopy.It is shown that the subsurface damage layer was gradually removed during the etching process and the surface was observed to be smoothened with the increase of the etching depth.This present work contributes a basic understanding of the linear field AP plasma etching performance with different gas composition and the typical characteristics would be further applied to damage-free precision removal of Si.
基金financial support by the Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi(OIT)Shanxi Province Hundred Talent Project
文摘In recent decade, Au nanoclusters of atomic precision （AunLm, where L= organic ligand： thiolate andphosphine） have been shown as a new promising nanogold catalyst. The well-defined AunLm catalystspossess unique electronic properties and frameworks, providing an excellent opportunity to correlate theintrinsic catalytic behavior with the cluster＇s framework as well as to study the catalytic mechanismsover gold nanoclusters. In this review, we only demonstrate the important roles of the gold nanoclustersin the oxygen activation （e.g., 302 to 102） and their selective oxidations in the presence of oxygen （e.g., COto C02, sulfides to sulfoxides, alcohol to aldehyde, styrene to styrene epoxide, amines to imines, andglucose to gluconic acid）. The size-specificity （Au25 （1.3 nm）, Au38 （].5 nm）, Au144 （1.9 nm）, etc.）, ligandengineering （e.g., aromatic vs aliphatic）, and doping effects （e.g., copper, silver, palladium, and platinum）are discussed in details. Finally, the proposed reactions＇ mechanism and the relationships of clusters＇structure and activity at the atomic level also are presented.
基金supports from the National Natural Science Foundation of China(Nos.22301012 from K.W.and 21978299 from Y.J.J.)the Research Foundation for Youth Scholars of Beijing Technology and Business University(No.QNJJ2022-23 from K.W.)+3 种基金the R&D Program of Beijing Municipal Education Commission(No.KM202310011005 from K.W.)the Research Foundation for Advanced Talents of Beijing Technology and Business University(No.19008020159 from Y.J.J.)Graduate Excellent Dissertation Cultivation Program of Beijing Technology and Business University(No.19008025082 from H.L.W.)the Shccig-Qinling Program(No.SMYJY202400134C from Y.J.J.).
文摘The regulation of electron transfer is crucial for enhancing the catalytic efficiency of catalysts.Currently,CO selective reduction of NO_(x)(CO-SCR)catalysts with surface synergistic oxygen vacancies(SSOVs)or alloyed components exhibit superior performance but face challenges of reduced activity and stability in oxygen-rich environments.Here,we demonstrate a strategy that combines PtCo alloys(0.01%Pt;0.04%Co)with SSOVs in cerium zirconium oxide solid solution to interactively modulate the electronic structure,resulting in a significant enhancement of both the activity and stability of the catalyst under oxygenrich conditions.This catalyst achieved over 85%NO conversion at 300℃ and 5%O_(2),while maintaining approximately 100%N2 selectivity during 20 h-stability testing,surpassing the performance of the monometallic catalysts.This enhancement arises from the synergistic electronic effects of alloying and SSOVs,which generate negatively charged Pt that facilitates NO adsorption and dissociation,while concurrently producing electron-deficient SSOVs that weaken O_(2) chemisorption and promote the formation of moderate reactive oxygen species.Moreover,the preferential adsorption of CO on Co sites alleviates competitive adsorption.
基金Project supported by the National Key Research and Development Program of China(No.2018YFB0406500)the Beijing Municipal Science and Technology Commission(No.Z181100004418009)the National Natural Science Foundation of China(No.51702313)
文摘We studied the effect of oxygen on the growth quality of diamond epitaxial layers. After oxygen is added during the growth of the diamond epitaxial layer, as the thickness of the epitaxial layer increases, the full width at half maximum of the rocking curve of the(004) plane of diamond epitaxial layer increases continuously, and, in addition, the intensities of both the Raman peaks and the free exciton emission peaks of the diamond epitaxial layer decrease continuously. These experimental results demonstrate that as the thickness of the diamond epitaxial layer increases, the quality of the diamond epitaxial layer degrades. The strong etching effect of the OH radical groups in the plasma on the diamond epilayers leads to the degradation of their crystallinity.
文摘The oxygen reduction kinetics on polycobaltprotoporphyrin(PCoPP)film has been examined with the rotating disc electrode technique in O_2-saturated solution of various pH.PCoPP film promotes the oxygen reduction process via two electrons to produce peroxide over wide pH range. When pH value of solution decreases,catalytic activity of PCoPP film increases.Possible catalytic mechanisms have been proposed for oxygen reduction.
基金supported by the National Natural Science Foundation of China (Grant No. 90921005)the Ministry of Science and Technology of China (Grant Nos. 2009CB929402 and 2011CBA00103)
文摘We have successfully synthesized Sr 2 CuO3+δ single crystals under high pressure and high temperature for the first time. The structure analysis show that this material crystallizes into tetragonal structure isostructural La 2 CuO4 with single CuO 2 plane. The magnetic susceptibility as well as resistance measurements indicates that the bulk superconductivity with the critical transition temperature 37 K is achieved in the crystal.
基金National Key R&D Program of China(2021YFA1500900)National Natural Science Foundation of China(21625604,21878272,22141001).
文摘The oxygen evolution reaction(OER)and electrochemical ozone production(EOP)attracted considerable attention due to their wide applications in electrocatalysis,but the detailed reaction mechanism of product formation as well as the voltage effect on O_(2)/O_(3)formation still remains unclear.In this work,density functional theory calculations were used to systematically investigate the possible reaction mechanisms of OER and EOP on the PbO_(2)(110)surface,with the possible reaction network involving surface lattice oxygen atoms(LOM)proposed.The results show that the LOM-2 reaction pathway involving two surface lattice oxygen atoms(Olatt)and one oxygen atom from H_(2)O was the most thermodynamically reactive.Different potential determining step(PDS)was obtained depending on the multiple reaction pathway,and the results show that the facile diffusion of Olattwould proceed the LOM pathway and promote the formation of surface oxygen vacancies(O_(vac1)/O_(vac2)).Furthermore,O_(vac1)/O_(vac2)formation on the surface would trigger further reactions of H_(2)O adsorption and splitting,which refilled the oxygen vacancy and ensured the considerable stability of the PbO_(2)(110)surface.Multiple H_(2)O dissociation pathways were proposed on PbO_(2)(110)with oxygen vacancy sites:the acid-base interaction mechanism and the vacancy fulfilling mechanism.
基金Acknowledgements The authors thank the financial support by the National Natural Science Foundation of China （No. 51273008 and 51473008）, the National High-Tech Research and Development Program （No. 2012AA030305）, the National Basic Research Program （No. 2012CB933200）, and NSF （No. CMMI-1400274 and AIR-IIP-1343270）.
文摘To commercialize fuel cells and metal-air batteries, cost-effective, highly active catalysts for the oxygen reduction reaction （ORR） must be developed. Herein, we describe the development of low-cost, heteroatom （N, P, Fe） ternary-doped, porous carbons （HDPC）. These materials are prepared by one-step pyrolysis of natural tea leaves treated with an iron salt, without any chemical and physical activation. The natural structure of the tea leaves provide a 3D hierarchical porous structure after carbonization. Moreover, heteroatom containing organic compounds in tea leaves act as precursors to functionalize the resultant carbon frameworks. In addition, we found that the polyphenols present in tea leaves act as ligands, reacting with Fe ions to form coordination compounds; these complexes acted as the precursors for Fe and N active sites. After pyrolysis, the as-prepared HDPC electrocatalysts, especially HDPC-800 （pyrolyzed at 800℃）, had more positive onsets, half-wave potentials, and higher catalytic activities for the ORR, which proceeds via a direct four-electron reaction pathway in alkaline media, similar to commercial Pt/C catalysts. Furthermore, HDPC-X also showed enhanced durability and better tolerance to methanol crossover and CO poisoning effects in comparison to commercial Pt/C, making them promising alternatives for state-of-the-art ORR electrocatalysts for electrochemical energy conversion. The method used here provides valuable guidelines for the design of high-performance ORR electrocatalysts from natural sources at the industrial scale.
