We report the magnetotransport and thermal properties of RuAs_(2) single crystal.RuAs_(2) exhibits semiconductor behavior and localization effect.The crossover from normal state to diffusive transport in the weak loca...We report the magnetotransport and thermal properties of RuAs_(2) single crystal.RuAs_(2) exhibits semiconductor behavior and localization effect.The crossover from normal state to diffusive transport in the weak localization(WL)state and then to variable range hopping(VRH)transport in the strong localization state has been observed.The transitions can be reflected in the measurement of resistivity and Seebeck coefficient.Negative magnetoresistance(NMR)emerges with the appearance of localization effect and is gradually suppressed in high magnetic field.The temperature dependent phase coherence length extracted from the fittings of NMR also indicates the transition from WL to VRH.The measurement of Hall effect reveals an anomaly of temperature dependent carrier concentration caused by localization effect.Our findings show that RuAs_(2) is a suitable platform to study the localized state.展开更多
Inhibitors are important for flotation separation of quartz and feldspar.In this study,a novel combined inhibitor was used to separate quartz and feldspar in near-neutral pulp.Selective inhibition of the combined inhi...Inhibitors are important for flotation separation of quartz and feldspar.In this study,a novel combined inhibitor was used to separate quartz and feldspar in near-neutral pulp.Selective inhibition of the combined inhibitor was assessed by micro-flotation experiments.And a series of detection methods were used to detect differences in the surface properties of feldspars and quartz after flotation reagents and put forward the synergistic strengthening mechanism.The outcomes were pointed out that pre-mixing combined inhibitors were more effective than the addition of Ca^(2+)and SS in sequence under the optimal proportion of 1:5.A concentrate from artificial mixed minerals that was characterized by a high quartz grade and a high recovery was acquired,and was found to be 90.70wt% and 83.70%,respectively.It was demonstrated that the combined inhibitor selectively prevented the action of the collector and feldspar from Fourier-transform infrared(FT-IR)and adsorption capacity tests.The results of X-ray photoelectron spectroscopy(XPS)indicated that Ca^(2+)directly interacts with the surface of quartz to increase the adsorption of collectors.In contrast,the chemistry property of Al on the feldspar surface was altered by combined inhibitor due to Na^(+)and Ca^(2+)taking the place of K^(+),resulting in the composite inhibitor forms a hydrophilic structure,which prevents the adsorption of the collector on the surface of feldspar by interacting with the Al active site.The combination of Ca^(2+)and SS synergically strengthens the difference of collecting property between quartz and feldspar by collector,thus achieving the effect of efficient separation.A new strategy for flotation to separate quartz from feldspar in near-neutral pulp was provided.展开更多
Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the pa...Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO_(2)/CO concentration at the electrode.Building upon this approach,we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO_(2)RR to C_(2+)in a neutral electrolyte.Employing CuO nanoparticles coated with hexaethynylbenzene organic molecules(HEB-CuO NPs),a remarkable C_(2+)Faradaic efficiency of nearly 90%was achieved at an unprecedented current density of 300 mA cm^(-2),and a high FE(>80%)was maintained at a wide range of current densities(100-600 mA cm^(-2))in neutral environments using a flow cell.Furthermore,in a membrane electrode assembly(MEA)electrolyzer,86.14%FEC2+was achieved at a partial current density of 387.6 mA cm^(-2)while maintaining continuous operation for over 50 h at a current density of 200 mA cm^(-2).In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K⋅H2O water increased the probability of intermediate reactants(CO)interacting with the surface,thereby promoting efficient C-C coupling and enhancing the yield of C_(2+)products.This advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C_(2+)production.展开更多
Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construc...Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construction of optimal local electronic structures for nitrogen‐coordinated Cu sites(Cu–N_(4))on carbon remains challenging.Here,we synthesized the Cu–N–C catalysts with atomically‐dispersed edge‐hosted Cu–N_(4) sites(Cu–N_(4)C_(8))located in a micropore between two graphitic sheets via a facile method to control the concentration of metal precursor.Edge‐hosted Cu–N_(4)C_(8) catalysts outperformed the previously reported M–N–C catalysts for CO_(2)‐to‐CO conversion,achieving a maximum CO Faradaic efficiency(FECO)of 96%,a CO current density of–8.97 mA cm^(–2) at–0.8 V versus reversible hydrogen electrode(RHE),and over FECO of 90%from–0.6 to–1.0 V versus RHE.Computational studies revealed that the micropore of the graphitic layer in edge‐hosted Cu–N_(4)C_(8) sites causes the d‐orbital energy level of the Cu atom to shift upward,which in return decreases the occupancy of antibonding states in the*COOH binding.This research suggests new insights into tailoring the locally coordinated structure of the electrocatalyst at the atomic scale to achieve highly selective electrocatalytic reactions.展开更多
BACKGROUND With the development of minimally invasive surgical techniques,the use of laparoscopic D2 radical surgery for the treatment of locally advanced gastric cancer(GC)has gradually increased.However,the effect o...BACKGROUND With the development of minimally invasive surgical techniques,the use of laparoscopic D2 radical surgery for the treatment of locally advanced gastric cancer(GC)has gradually increased.However,the effect of this procedure on survival and prognosis remains controversial.This study evaluated the survival and prognosis of patients receiving laparoscopic D2 radical resection for the treatment of locally advanced GC to provide more reliable clinical evidence,guide clinical decision-making,optimize treatment strategies,and improve the survival rate and quality of life of patients.METHODS A retrospective cohort study was performed.Clinicopathological data from 652 patients with locally advanced GC in our hospitals from December 2013 to December 2023 were collected.There were 442 males and 210 females.The mean age was 57±12 years.All patients underwent a laparoscopic D2 radical operation for distal GC.The patients were followed up in the outpatient department and by telephone to determine their tumor recurrence,metastasis,and survival.The follow-up period ended in December 2023.Normally distributed data are expressed as the mean±SD,and normally distributed data are expressed as M(Q1,Q3)or M(range).Statistical data are expressed as absolute numbers or percentages;theχ^(2) test was used for comparisons between groups,and the Mann-Whitney U nonparametric test was used for comparisons of rank data.The life table method was used to calculate the survival rate,the Kaplan-Meier method was used to construct survival curves,the log rank test was used for survival analysis,and the Cox risk regression model was used for univariate and multifactor analysis.RESULTS The median overall survival(OS)time for the 652 patients was 81 months,with a 10-year OS rate of 46.1%.Patients with TNM stages II and III had 10-year OS rates of 59.6%and 37.5%,respectively,which were significantly different(P<0.05).Univariate analysis indicated that factors such as age,maximum tumor diameter,tumor diffe-rentiation grade(low to undifferentiated),pathological TNM stage,pathological T stage,pathological N stage(N2,N3),and postoperative chemotherapy significantly influenced the 10-year OS rate for patients with locally advanced GC following laparoscopic D2 radical resection for distal stomach cancer[hazard ratio(HR):1.45,1.64,1.45,1.64,1.37,2.05,1.30,1.68,3.08,and 0.56 with confidence intervals(CIs)of 1.15-1.84,1.32-2.03,1.05-1.77,1.62-2.59,1.05-1.61,1.17-2.42,2.15-4.41,and 0.44-0.70,respectively;P<0.05].Multifactor analysis revealed that a tumor diameter greater than 4 cm,low tumor differentiation,and pathological TNM stage III were independent risk factors for the 10-year OS rate in these patients(HR:1.48,1.44,1.81 with a 95%CI:1.19-1.84).Additionally,postoperative chemotherapy emerged as an independent protective factor for the 10-year OS rate(HR:0.57,95%CI:0.45-0.73;P<0.05).CONCLUSION A maximum tumor diameter exceeding 4 cm,low tumor differentiation,and pathological TNM stage III were identified as independent risk factors for the 10-year OS rate in patients with locally advanced GC following laparoscopic D2 radical resection for distal GC.Conversely,postoperative chemotherapy was found to be an independent protective factor for the 10-year OS rate in these patients.展开更多
Plasma membrane (PM) Ca2+-ATPase activity in poplar apical bud meristematic cells during short-day (SD)-induced dormancy development was examined by a cerium precipitation EM-cytochemical method. Ca2+-ATPase activ...Plasma membrane (PM) Ca2+-ATPase activity in poplar apical bud meristematic cells during short-day (SD)-induced dormancy development was examined by a cerium precipitation EM-cytochemical method. Ca2+-ATPase activity, indicated by the status of cerium phosphate precipitated grains, was localized mainly on the interior face (cytoplasmic side) of the PM when plants were grown under long days and reached a deep dormancy. A few reaction products were also observed on the nuclear envelope.When plant buds were developing dormancy after 28 to 42 d of SD exposure, almost no reaction products were present on the interior face of the PM. In contrast, a large number of cerium phosphate precipitated grains were distributed on the exterior face of the PM. After 70 d of SD exposure, when buds had developed a deep dormancy, the reaction products of Ca2+-ATPase activity again appeared on the interior face of the PM. The results seemed suggesting that two kinds of Ca2+-ATPases may be present on the PM during the SD-induced dormancy in poplar.One is the Ca2+-punlping ATPase, which is located on the interior face of the PM, for maintaining and restoring the Ca2+homeostasis. The other might be an ecto-Ca2+-ATPase, which is located on the exterior face of the PM, for the exocytosis of cell wall materials as suggested by the fact of the cell wall thickening during the dormancy developlnent in poplar.展开更多
基金Project supported by the National Key Research and Development Program of China (Grant Nos.2023YFA1406500 and 2019YFA0308602)the National Natural Science Foundation of China (Grant Nos.12104011,12274388,12074425,52102333,12104010,12204004,and 11874422)the Natural Science Foundation of Anhui Province (Grant Nos.2108085QA22 and 2108085MA16)。
文摘We report the magnetotransport and thermal properties of RuAs_(2) single crystal.RuAs_(2) exhibits semiconductor behavior and localization effect.The crossover from normal state to diffusive transport in the weak localization(WL)state and then to variable range hopping(VRH)transport in the strong localization state has been observed.The transitions can be reflected in the measurement of resistivity and Seebeck coefficient.Negative magnetoresistance(NMR)emerges with the appearance of localization effect and is gradually suppressed in high magnetic field.The temperature dependent phase coherence length extracted from the fittings of NMR also indicates the transition from WL to VRH.The measurement of Hall effect reveals an anomaly of temperature dependent carrier concentration caused by localization effect.Our findings show that RuAs_(2) is a suitable platform to study the localized state.
基金the financial support from the National Key Research and Development Program of China(No.2018YFC1903403)Young Elite Scientists Sponsorship Program by CAST(No.2022QNRC001).
文摘Inhibitors are important for flotation separation of quartz and feldspar.In this study,a novel combined inhibitor was used to separate quartz and feldspar in near-neutral pulp.Selective inhibition of the combined inhibitor was assessed by micro-flotation experiments.And a series of detection methods were used to detect differences in the surface properties of feldspars and quartz after flotation reagents and put forward the synergistic strengthening mechanism.The outcomes were pointed out that pre-mixing combined inhibitors were more effective than the addition of Ca^(2+)and SS in sequence under the optimal proportion of 1:5.A concentrate from artificial mixed minerals that was characterized by a high quartz grade and a high recovery was acquired,and was found to be 90.70wt% and 83.70%,respectively.It was demonstrated that the combined inhibitor selectively prevented the action of the collector and feldspar from Fourier-transform infrared(FT-IR)and adsorption capacity tests.The results of X-ray photoelectron spectroscopy(XPS)indicated that Ca^(2+)directly interacts with the surface of quartz to increase the adsorption of collectors.In contrast,the chemistry property of Al on the feldspar surface was altered by combined inhibitor due to Na^(+)and Ca^(2+)taking the place of K^(+),resulting in the composite inhibitor forms a hydrophilic structure,which prevents the adsorption of the collector on the surface of feldspar by interacting with the Al active site.The combination of Ca^(2+)and SS synergically strengthens the difference of collecting property between quartz and feldspar by collector,thus achieving the effect of efficient separation.A new strategy for flotation to separate quartz from feldspar in near-neutral pulp was provided.
基金supported by the National Natural Science Foundation of China(22101182)the Shenzhen Science and Technology Program(Nos.JCYJ20210324095202006,JCYJ20220531095813031,and JCYJ20230807140700001)Guangdong Basic and Applied Basic Research Foundation(2022A1515010318).
文摘Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO_(2)/CO concentration at the electrode.Building upon this approach,we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO_(2)RR to C_(2+)in a neutral electrolyte.Employing CuO nanoparticles coated with hexaethynylbenzene organic molecules(HEB-CuO NPs),a remarkable C_(2+)Faradaic efficiency of nearly 90%was achieved at an unprecedented current density of 300 mA cm^(-2),and a high FE(>80%)was maintained at a wide range of current densities(100-600 mA cm^(-2))in neutral environments using a flow cell.Furthermore,in a membrane electrode assembly(MEA)electrolyzer,86.14%FEC2+was achieved at a partial current density of 387.6 mA cm^(-2)while maintaining continuous operation for over 50 h at a current density of 200 mA cm^(-2).In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K⋅H2O water increased the probability of intermediate reactants(CO)interacting with the surface,thereby promoting efficient C-C coupling and enhancing the yield of C_(2+)products.This advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C_(2+)production.
基金National Research Foundation of Korea,Grant/Award Numbers:NRF‐2019M3D1A1079303,NRF‐2021R1A2C1011415,NRF‐2021R1A2C3004019。
文摘Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construction of optimal local electronic structures for nitrogen‐coordinated Cu sites(Cu–N_(4))on carbon remains challenging.Here,we synthesized the Cu–N–C catalysts with atomically‐dispersed edge‐hosted Cu–N_(4) sites(Cu–N_(4)C_(8))located in a micropore between two graphitic sheets via a facile method to control the concentration of metal precursor.Edge‐hosted Cu–N_(4)C_(8) catalysts outperformed the previously reported M–N–C catalysts for CO_(2)‐to‐CO conversion,achieving a maximum CO Faradaic efficiency(FECO)of 96%,a CO current density of–8.97 mA cm^(–2) at–0.8 V versus reversible hydrogen electrode(RHE),and over FECO of 90%from–0.6 to–1.0 V versus RHE.Computational studies revealed that the micropore of the graphitic layer in edge‐hosted Cu–N_(4)C_(8) sites causes the d‐orbital energy level of the Cu atom to shift upward,which in return decreases the occupancy of antibonding states in the*COOH binding.This research suggests new insights into tailoring the locally coordinated structure of the electrocatalyst at the atomic scale to achieve highly selective electrocatalytic reactions.
文摘BACKGROUND With the development of minimally invasive surgical techniques,the use of laparoscopic D2 radical surgery for the treatment of locally advanced gastric cancer(GC)has gradually increased.However,the effect of this procedure on survival and prognosis remains controversial.This study evaluated the survival and prognosis of patients receiving laparoscopic D2 radical resection for the treatment of locally advanced GC to provide more reliable clinical evidence,guide clinical decision-making,optimize treatment strategies,and improve the survival rate and quality of life of patients.METHODS A retrospective cohort study was performed.Clinicopathological data from 652 patients with locally advanced GC in our hospitals from December 2013 to December 2023 were collected.There were 442 males and 210 females.The mean age was 57±12 years.All patients underwent a laparoscopic D2 radical operation for distal GC.The patients were followed up in the outpatient department and by telephone to determine their tumor recurrence,metastasis,and survival.The follow-up period ended in December 2023.Normally distributed data are expressed as the mean±SD,and normally distributed data are expressed as M(Q1,Q3)or M(range).Statistical data are expressed as absolute numbers or percentages;theχ^(2) test was used for comparisons between groups,and the Mann-Whitney U nonparametric test was used for comparisons of rank data.The life table method was used to calculate the survival rate,the Kaplan-Meier method was used to construct survival curves,the log rank test was used for survival analysis,and the Cox risk regression model was used for univariate and multifactor analysis.RESULTS The median overall survival(OS)time for the 652 patients was 81 months,with a 10-year OS rate of 46.1%.Patients with TNM stages II and III had 10-year OS rates of 59.6%and 37.5%,respectively,which were significantly different(P<0.05).Univariate analysis indicated that factors such as age,maximum tumor diameter,tumor diffe-rentiation grade(low to undifferentiated),pathological TNM stage,pathological T stage,pathological N stage(N2,N3),and postoperative chemotherapy significantly influenced the 10-year OS rate for patients with locally advanced GC following laparoscopic D2 radical resection for distal stomach cancer[hazard ratio(HR):1.45,1.64,1.45,1.64,1.37,2.05,1.30,1.68,3.08,and 0.56 with confidence intervals(CIs)of 1.15-1.84,1.32-2.03,1.05-1.77,1.62-2.59,1.05-1.61,1.17-2.42,2.15-4.41,and 0.44-0.70,respectively;P<0.05].Multifactor analysis revealed that a tumor diameter greater than 4 cm,low tumor differentiation,and pathological TNM stage III were independent risk factors for the 10-year OS rate in these patients(HR:1.48,1.44,1.81 with a 95%CI:1.19-1.84).Additionally,postoperative chemotherapy emerged as an independent protective factor for the 10-year OS rate(HR:0.57,95%CI:0.45-0.73;P<0.05).CONCLUSION A maximum tumor diameter exceeding 4 cm,low tumor differentiation,and pathological TNM stage III were identified as independent risk factors for the 10-year OS rate in patients with locally advanced GC following laparoscopic D2 radical resection for distal GC.Conversely,postoperative chemotherapy was found to be an independent protective factor for the 10-year OS rate in these patients.
文摘Plasma membrane (PM) Ca2+-ATPase activity in poplar apical bud meristematic cells during short-day (SD)-induced dormancy development was examined by a cerium precipitation EM-cytochemical method. Ca2+-ATPase activity, indicated by the status of cerium phosphate precipitated grains, was localized mainly on the interior face (cytoplasmic side) of the PM when plants were grown under long days and reached a deep dormancy. A few reaction products were also observed on the nuclear envelope.When plant buds were developing dormancy after 28 to 42 d of SD exposure, almost no reaction products were present on the interior face of the PM. In contrast, a large number of cerium phosphate precipitated grains were distributed on the exterior face of the PM. After 70 d of SD exposure, when buds had developed a deep dormancy, the reaction products of Ca2+-ATPase activity again appeared on the interior face of the PM. The results seemed suggesting that two kinds of Ca2+-ATPases may be present on the PM during the SD-induced dormancy in poplar.One is the Ca2+-punlping ATPase, which is located on the interior face of the PM, for maintaining and restoring the Ca2+homeostasis. The other might be an ecto-Ca2+-ATPase, which is located on the exterior face of the PM, for the exocytosis of cell wall materials as suggested by the fact of the cell wall thickening during the dormancy developlnent in poplar.