Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient...Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient knowledge about the impact of metal exposure on its inhabitants.In this study,deep-sea mussel Gigantidas platifrons,a commonly used deep-sea toxicology model organism,was exposed to manganese(100,1000μg/L)or iron(500,5000μg/L)for 7 d,respectively.Manganese and iron were chosen for their high levels of occurrence within deep-sea deposits.Metal accumulation and a battery of biochemical biomarkers related to antioxidative stress in superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA);immune function in alkaline phosphatase(AKP),acid phosphatase(ACP);and energy metabolism in pyruvate kinase(PK)and hexokinase(HK)were assessed in mussel gills.Results showed that deep-sea mussel G.platifrons exhibited a high capacity to accumulate Mn/Fe.In addition,most tested biochemical parameters were altered by metal exposure,demonstrating that metals could induce oxidative stress,suppress the immune system,and affect energy metabolism of deep-sea mussels.The integrated biomarker response(IBR)approach indicated that the exposure to Mn/Fe had a negative impact on deep-sea mussels,and Mn demonstrated a more harmful impact on deep-sea mussels than Fe.Additionally,SOD and CAT biomarkers had the greatest impact on IBR values in Mn treatments,while ACP and HK were most influential for the low-and high-dose Fe groups,respectively.This study represents the first application of the IBR approach to evaluate the toxicity of metals on deep-sea fauna and serves as a crucial framework for risk assessment of deep-sea mining-associated metal exposure.展开更多
Light-induced ultrafast spin dynamics in materials is of great importance for developments of spintronics and magnetic storage technology.Recent progresses include ultrafast demagnetization,magnetic switching,and magn...Light-induced ultrafast spin dynamics in materials is of great importance for developments of spintronics and magnetic storage technology.Recent progresses include ultrafast demagnetization,magnetic switching,and magnetic phase transitions,while the ultrafast generation of magnetism is hardly achieved.Here,a strong lightinduced magnetization(up to 0.86μBper formula unit)is identified in non-magnetic monolayer molybdenum disulfide(MoS_(2)).With the state-of-the-art time-dependent density functional theory simulations,we demonstrate that the out-of-plane magnetization can be induced by circularly polarized laser,where chiral phonons play a vital role.The phonons strongly modulate spin-orbital interactions and promote electronic transitions between the two conduction band states,achieving an effective magnetic field~380 T.Our study provides important insights into the ultrafast magnetization and spin-phonon coupling dynamics,facilitating effective light-controlled valleytronics and magnetism.展开更多
AIM: To explore the role of CDX2 in the multi-drug resistance (MDR) process of gastric cancer in vitro and in vivo . METHODS: A cisplatin-resistant gastric cancer cell line with stable downregulation of CDX2 was estab...AIM: To explore the role of CDX2 in the multi-drug resistance (MDR) process of gastric cancer in vitro and in vivo . METHODS: A cisplatin-resistant gastric cancer cell line with stable downregulation of CDX2 was established. mRNA and protein expression levels of CDX2, survivin, cyclin D1, and c-Myc were detected by western blotting and semi-quantitative reverse-transcriptase polymerase chain reaction (RT-PCR). The influence of downregulation of CDX2 on MDR was assessed by measuring IC50 of SGC7901/DDP cells to cisplatin, doxorubicin, and 5-fluorouracil, rate of doxorubicin efflux, apoptosis, and cell cycle progression detected by flow cytometry. In addition, we determined the in vivo effects of CDX2 small interfering RNA (siRNA) on tumor size, and apoptotic cells in tumor tissues were detected by deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling and hematoxylin and eosin staining. RESULTS: CDX2 siRNA led to downregulation of endogenous CDX2 mRNA (0.31 ± 0.05 vs 1.10 ± 0.51, 0.31 ± 0.05 vs 1.05 ± 0.21, P = 0.003) and protein (0.12 ± 0.08 vs 0.51 ± 0.07, 0.12 ± 0.08 vs 0.55 ± 0.16, P = 2.57 × 10 -4) expression. It significantly promoted the sensitivity of SGC7901/DDP cells to cisplatin (0.12 ± 0.05 vs 0.33 ± 0.08, 0.12 ± 0.05 vs 0.39 ± 0.15, P = 0.001), doxorubicin (0.52 ± 0.13 vs 4.11 ± 1.25, 0.52 ± 0.13 vs 4.05 ± 1.44, P = 2.81 × 10-4), and 5-fluorouracil (0.82 ± 0.13 vs 2.81 ± 0.51, 0.82 ± 0.13 vs 3.28 ± 1.03, P = 1.71 × 10-4). Flow cytometry confirmed that the percentage of apoptotic cells increased after CDX2 downregulation (32.15% ± 2.15% vs 17.63% ± 3.16%, 32.15% ± 2.15% vs 19.3% ± 2.25%, P = 1.73 × 10-6). This notion was further supported by the observation that downregulation of CDX2 blocked entry into the S-phase of the cell cycle (31.53% ± 3.78% vs 65.05% ± 7.25%, 31.53% ± 3.78% vs 62.27% ± 5.02%, P = 7.55 × 10-7). Furthermore, downregulation of CDX2 significantly increased intracellular accumulation of doxorubicin (0.21 ± 0.06 vs 0.41 ± 0.11, 0.21 ± 0.06 vs 0.40 ± 0.08, P = 0.003). In molecular studies, semiquantitative RT-PCR and western blotting revealed that CDX2 downregulation could inhibit expression of c-Myc, survivin and cyclin D1. CONCLUSION: CDX2 may be involved in regulating multiple signaling pathways in reversing MDR, suggesting that CDX2 may represent a novel target for gastric cancer therapy.展开更多
We present the case of a 35-year-old male foundry worker with painful burns after exposure to splashing 1500°C molten steel. This rare case involves a localized occupational-related molten steel burn on the cervi...We present the case of a 35-year-old male foundry worker with painful burns after exposure to splashing 1500°C molten steel. This rare case involves a localized occupational-related molten steel burn on the cervicofacial region. The lesion was induced by hyperthermal contact of the skin with molten steel. This case report highlights a modified moist occluded burn therapy that is applied using a combination of modified chitin wound rehabilitating biogel (AmPoSa (?)) and sterile polyethylene film. The patient in our report achieved favourable aesthetic restoration without residual scars and hyperpigmented areas.展开更多
We investigated correlation of the slope of the initial part of P-wave envelope, hypocenter depth and plate boundaries by B-Δ method, which is used to determine epicentral distances in the Japan Meteorological Agency...We investigated correlation of the slope of the initial part of P-wave envelope, hypocenter depth and plate boundaries by B-Δ method, which is used to determine epicentral distances in the Japan Meteorological Agency and Japan Railway Company earthquake early warning(EEW) systems. The Tohoku region was chosen as the study region. 19,899 strong motion data for 265 events with magnitudes in the range from 5.0 to 7.6 from KiK-net(Kiban Kyoshin network) had been collected. The coefficient c to investigate is obtained from the linear relation between log B and log Δ. Compared to the hypocenter depth, the coefficients c of events is more likely to decide by the spatial correlation of the plate boundaries. The differences are likely to be due to earthquake characteristics, since deeper events in the subducting slabs the structural effects are likely to be larger than or comparable to those for shallow crust events.展开更多
Severe thermal burns usually result in complex facial problems such as contracture and formation of hyper/hypopigmentation,contracture,hypertrophic scars or deformity,with patients often requiring reconstructive surge...Severe thermal burns usually result in complex facial problems such as contracture and formation of hyper/hypopigmentation,contracture,hypertrophic scars or deformity,with patients often requiring reconstructive surgery.Therefore,seeking a superior and reliable burn therapy remains a great challenge for plastic and burn surgeons.However,the optimal treatment of thermal injuries remains controversial.In the 1960s,a new therapeutic concept,that sterile polyethylene film might be used as a type of moist occlusive dressing,was successively proposed.Below we present a hypothesis that combined utilization of sterile polyethylene film and burn cream may be a novel and superior therapeutic approach for thermal burns.To distinguish this method from traditional moist burn therapy,this new therapy we proposed is named modified moist occlusive burn therapy(MMOBT).展开更多
It is significant to optimize geometric configuration of metal catalytic sites and boost their catalytic activity.Herein,we synthesized isolated single Zn-N_(4)sites on N-doped carbon(Zn-CN)by pyrolyzing zeolite imida...It is significant to optimize geometric configuration of metal catalytic sites and boost their catalytic activity.Herein,we synthesized isolated single Zn-N_(4)sites on N-doped carbon(Zn-CN)by pyrolyzing zeolite imidazole framework-8(ZIF-8)at different temperatures.For the reciprocal transformation between benzyl alcohol and benzaldehyde,the catalytic activities of Zn-CN catalysts exhibited a volcano-like trend as the pyrolysis temperatures increased.The optimal catalyst was Zn-CN-900,with outstanding catalytic activity exceeding commercial 20 wt.%Pd/C and 20 wt.%Pt/C,promising to substitute the noble metalbased catalysts.X-ray absorption near-edge structure(XANES)measurements and density functional theory(DFT)calculation revealed the gradual transformation from tetrahedral ZnN_(4)sites of ZIF-8 into planar ZnN_(4)sites above 700℃,with the maximum planar ZnN_(4)sites in Zn-CN-900.The stronger adsorption between reactants and planar ZnN_(4)sites facilitated the activation of reactants compared with tetrahedral ZnN_(4)sites.This work will provide valuable insight into rational design of efficient catalysts by optimizing geometric configuration of catalytic sites.展开更多
EPW is an open-source software for ab initio calculations of electron–phonon interactions and related materials properties.The code combines density functional perturbation theory and maximally localized Wannier func...EPW is an open-source software for ab initio calculations of electron–phonon interactions and related materials properties.The code combines density functional perturbation theory and maximally localized Wannier functions to efficiently compute electron–phonon coupling matrix elements,and to perform predictive calculations of temperature-dependent properties and phonon-assisted quantum processes in bulk solids and low-dimensional materials.Here,we report on significant developments in the code since 2016,namely:a transport module for the calculation of charge carrier mobility under electric and magnetic fields using the Boltzmann transport equation;a superconductivity module for calculations of phonon-mediated superconductors using the anisotropic multi-band Eliashberg theory;an optics module for calculations of phonon-assisted indirect transitions;a module for the calculation of small and large polarons without supercells;and a module for calculating band structure renormalization and temperature-dependent optical spectra using the special displacement method.For each capability,we outline the methodology and implementation and provide example calculations.展开更多
Electronic adjustment is one of the most commonly used strategies to improve the catalytic performance of heterogeneous catalysts. We prepared hexagonal ultrathin Pd nanosheets with edges modified by gold nanoparticl...Electronic adjustment is one of the most commonly used strategies to improve the catalytic performance of heterogeneous catalysts. We prepared hexagonal ultrathin Pd nanosheets with edges modified by gold nanoparticles (Au@Pd nanosheets) using galvanic replacement method. By virtue of the electronic interactions between the Pd nanosheets and Au nanoparticles, the Au@Pd nanosheets exhibited excellent catalytic performances in the carbonylation of iodobenzene by carbon monoxide. The novel nanocomposites could be applied as model catalysts to explore electronic effects in catalysis.展开更多
An efficient, controllable, and facile two-step synthetic strategy to prepare graphene-based nanocomposites is proposed. A series of Fe3O4-decorated reduced graphene oxide (Fe3O4@RGO) nanocomposites incorporating Fe...An efficient, controllable, and facile two-step synthetic strategy to prepare graphene-based nanocomposites is proposed. A series of Fe3O4-decorated reduced graphene oxide (Fe3O4@RGO) nanocomposites incorporating Fe3O4 nanocrystals of various sizes were prepared by an ethanothermal method using graphene oxide (GO) and monodisperse Fe3O4 nanocrystals with diameters ranging from 4 to 10 nm. The morphologies and microstructures of the as-prepared composites were characterized by X-ray diffraction, Raman spectroscopy, nitrogen adsorption measurements, and transmission electron microscopy. The results show that GO can be reduced to graphene during the ethanothermal process, and that the Fe3O4 nanocrystals are well dispersed on the graphene sheets generated in the process. The analysis of the electrochemical properties of the Fe3O4@RGO materials shows that nanocomposites prepared with Fe3O4 nanocrystals of different sizes exhibit different electrochemical performances. Among all samples, FegO4@RGO prepared with Fe3O4 nanocrystals of 6 nm diameter possessed the highest specific capacitance of 481 F/g at 1 A/g, highlighting the excellent capability of this material. This work illustrates a promising route to develop graphene-based nanocomposite materials with a wide range of potential applications.展开更多
基金Supported by the Marine S&T Fund of Shandong Province for Qingdao Marine Science and Technology Center(No.2022QNLM030004-1)the National Natural Science Foundation of China(Nos.42276153,42030407)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB42020401)the Key Research Program of Frontier Sciences,CAS(No.ZDBS-LY-DQC032)the National Key R&D Program of China(No.2022YFC2804003)。
文摘Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient knowledge about the impact of metal exposure on its inhabitants.In this study,deep-sea mussel Gigantidas platifrons,a commonly used deep-sea toxicology model organism,was exposed to manganese(100,1000μg/L)or iron(500,5000μg/L)for 7 d,respectively.Manganese and iron were chosen for their high levels of occurrence within deep-sea deposits.Metal accumulation and a battery of biochemical biomarkers related to antioxidative stress in superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA);immune function in alkaline phosphatase(AKP),acid phosphatase(ACP);and energy metabolism in pyruvate kinase(PK)and hexokinase(HK)were assessed in mussel gills.Results showed that deep-sea mussel G.platifrons exhibited a high capacity to accumulate Mn/Fe.In addition,most tested biochemical parameters were altered by metal exposure,demonstrating that metals could induce oxidative stress,suppress the immune system,and affect energy metabolism of deep-sea mussels.The integrated biomarker response(IBR)approach indicated that the exposure to Mn/Fe had a negative impact on deep-sea mussels,and Mn demonstrated a more harmful impact on deep-sea mussels than Fe.Additionally,SOD and CAT biomarkers had the greatest impact on IBR values in Mn treatments,while ACP and HK were most influential for the low-and high-dose Fe groups,respectively.This study represents the first application of the IBR approach to evaluate the toxicity of metals on deep-sea fauna and serves as a crucial framework for risk assessment of deep-sea mining-associated metal exposure.
基金supported by the National Key R&D Program of China(Grant No.2021YFA1400201)the National Natural Science Foundation of China(Grant Nos.12025407 and 11934004)Chinese Academy of Sciences(Grant Nos.XDB330301 and YSBR047)。
文摘Light-induced ultrafast spin dynamics in materials is of great importance for developments of spintronics and magnetic storage technology.Recent progresses include ultrafast demagnetization,magnetic switching,and magnetic phase transitions,while the ultrafast generation of magnetism is hardly achieved.Here,a strong lightinduced magnetization(up to 0.86μBper formula unit)is identified in non-magnetic monolayer molybdenum disulfide(MoS_(2)).With the state-of-the-art time-dependent density functional theory simulations,we demonstrate that the out-of-plane magnetization can be induced by circularly polarized laser,where chiral phonons play a vital role.The phonons strongly modulate spin-orbital interactions and promote electronic transitions between the two conduction band states,achieving an effective magnetic field~380 T.Our study provides important insights into the ultrafast magnetization and spin-phonon coupling dynamics,facilitating effective light-controlled valleytronics and magnetism.
基金Supported by Grants from the Natural Science Foundation of China, No. 81060201Natural Science Foundation of Guangxi,No. 2011GXNSFA018273 and No. 2013GXNSFAA019163the Key Health Science Foundation of Guangxi, No. 1298003-2-6
文摘AIM: To explore the role of CDX2 in the multi-drug resistance (MDR) process of gastric cancer in vitro and in vivo . METHODS: A cisplatin-resistant gastric cancer cell line with stable downregulation of CDX2 was established. mRNA and protein expression levels of CDX2, survivin, cyclin D1, and c-Myc were detected by western blotting and semi-quantitative reverse-transcriptase polymerase chain reaction (RT-PCR). The influence of downregulation of CDX2 on MDR was assessed by measuring IC50 of SGC7901/DDP cells to cisplatin, doxorubicin, and 5-fluorouracil, rate of doxorubicin efflux, apoptosis, and cell cycle progression detected by flow cytometry. In addition, we determined the in vivo effects of CDX2 small interfering RNA (siRNA) on tumor size, and apoptotic cells in tumor tissues were detected by deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling and hematoxylin and eosin staining. RESULTS: CDX2 siRNA led to downregulation of endogenous CDX2 mRNA (0.31 ± 0.05 vs 1.10 ± 0.51, 0.31 ± 0.05 vs 1.05 ± 0.21, P = 0.003) and protein (0.12 ± 0.08 vs 0.51 ± 0.07, 0.12 ± 0.08 vs 0.55 ± 0.16, P = 2.57 × 10 -4) expression. It significantly promoted the sensitivity of SGC7901/DDP cells to cisplatin (0.12 ± 0.05 vs 0.33 ± 0.08, 0.12 ± 0.05 vs 0.39 ± 0.15, P = 0.001), doxorubicin (0.52 ± 0.13 vs 4.11 ± 1.25, 0.52 ± 0.13 vs 4.05 ± 1.44, P = 2.81 × 10-4), and 5-fluorouracil (0.82 ± 0.13 vs 2.81 ± 0.51, 0.82 ± 0.13 vs 3.28 ± 1.03, P = 1.71 × 10-4). Flow cytometry confirmed that the percentage of apoptotic cells increased after CDX2 downregulation (32.15% ± 2.15% vs 17.63% ± 3.16%, 32.15% ± 2.15% vs 19.3% ± 2.25%, P = 1.73 × 10-6). This notion was further supported by the observation that downregulation of CDX2 blocked entry into the S-phase of the cell cycle (31.53% ± 3.78% vs 65.05% ± 7.25%, 31.53% ± 3.78% vs 62.27% ± 5.02%, P = 7.55 × 10-7). Furthermore, downregulation of CDX2 significantly increased intracellular accumulation of doxorubicin (0.21 ± 0.06 vs 0.41 ± 0.11, 0.21 ± 0.06 vs 0.40 ± 0.08, P = 0.003). In molecular studies, semiquantitative RT-PCR and western blotting revealed that CDX2 downregulation could inhibit expression of c-Myc, survivin and cyclin D1. CONCLUSION: CDX2 may be involved in regulating multiple signaling pathways in reversing MDR, suggesting that CDX2 may represent a novel target for gastric cancer therapy.
基金supported by the National Science Foundation for Outstanding Young Scholars of China (No.51222405)the National Natural Science Foundation of China (No.51034002)+1 种基金the Fok Ying-Tong Education Foundation (No.132002)the Major State Basic Research and Development Program of China (No.2011CB610405)
文摘We present the case of a 35-year-old male foundry worker with painful burns after exposure to splashing 1500°C molten steel. This rare case involves a localized occupational-related molten steel burn on the cervicofacial region. The lesion was induced by hyperthermal contact of the skin with molten steel. This case report highlights a modified moist occluded burn therapy that is applied using a combination of modified chitin wound rehabilitating biogel (AmPoSa (?)) and sterile polyethylene film. The patient in our report achieved favourable aesthetic restoration without residual scars and hyperpigmented areas.
基金supported by the Director Foundation of the Institute of Seismology,China Earthquake Administration,China(IS200756046)
文摘We investigated correlation of the slope of the initial part of P-wave envelope, hypocenter depth and plate boundaries by B-Δ method, which is used to determine epicentral distances in the Japan Meteorological Agency and Japan Railway Company earthquake early warning(EEW) systems. The Tohoku region was chosen as the study region. 19,899 strong motion data for 265 events with magnitudes in the range from 5.0 to 7.6 from KiK-net(Kiban Kyoshin network) had been collected. The coefficient c to investigate is obtained from the linear relation between log B and log Δ. Compared to the hypocenter depth, the coefficients c of events is more likely to decide by the spatial correlation of the plate boundaries. The differences are likely to be due to earthquake characteristics, since deeper events in the subducting slabs the structural effects are likely to be larger than or comparable to those for shallow crust events.
文摘Severe thermal burns usually result in complex facial problems such as contracture and formation of hyper/hypopigmentation,contracture,hypertrophic scars or deformity,with patients often requiring reconstructive surgery.Therefore,seeking a superior and reliable burn therapy remains a great challenge for plastic and burn surgeons.However,the optimal treatment of thermal injuries remains controversial.In the 1960s,a new therapeutic concept,that sterile polyethylene film might be used as a type of moist occlusive dressing,was successively proposed.Below we present a hypothesis that combined utilization of sterile polyethylene film and burn cream may be a novel and superior therapeutic approach for thermal burns.To distinguish this method from traditional moist burn therapy,this new therapy we proposed is named modified moist occlusive burn therapy(MMOBT).
基金This work was supported by the National Postdoctoral Program for Innovative Talents(No.BX20220159)the National Natural Science Foundation of China(No.21890383)。
文摘It is significant to optimize geometric configuration of metal catalytic sites and boost their catalytic activity.Herein,we synthesized isolated single Zn-N_(4)sites on N-doped carbon(Zn-CN)by pyrolyzing zeolite imidazole framework-8(ZIF-8)at different temperatures.For the reciprocal transformation between benzyl alcohol and benzaldehyde,the catalytic activities of Zn-CN catalysts exhibited a volcano-like trend as the pyrolysis temperatures increased.The optimal catalyst was Zn-CN-900,with outstanding catalytic activity exceeding commercial 20 wt.%Pd/C and 20 wt.%Pt/C,promising to substitute the noble metalbased catalysts.X-ray absorption near-edge structure(XANES)measurements and density functional theory(DFT)calculation revealed the gradual transformation from tetrahedral ZnN_(4)sites of ZIF-8 into planar ZnN_(4)sites above 700℃,with the maximum planar ZnN_(4)sites in Zn-CN-900.The stronger adsorption between reactants and planar ZnN_(4)sites facilitated the activation of reactants compared with tetrahedral ZnN_(4)sites.This work will provide valuable insight into rational design of efficient catalysts by optimizing geometric configuration of catalytic sites.
基金This research is supported by:the Computational Materials Sciences Program funded by the U.S.Department of Energy,Office of Science,Basic Energy Sciences,under Award No.DE-SC0020129(project coordination,scale-up,polaron module,transport module,optics module,special displacement module)the National Science Foundation,Office of Advanced Cyberinfrastructure and Division of Materials Research under Grants Nos.2103991 and 2035518(superconductivity module,interoperability)+12 种基金the NSF Characteristic Science Applications for the Leadership Class Computing Facility program under Grant No.2139536(prepara-tion for LCCF)the Fond National de la Recherche Scientifique of Belgium(F.R.S.-FNRS)and the European Union’s Horizon 2020 research and innovation program under grant agreements No.881603-Graphene Core3(transport module)the NSF DMREF award 2119555(quasi-degenerate perturbation theory module)This research used resources of the National Energy Research Scientific Computing Center and the Argonne Leadership Computing Facility,which are DOE Office of Science User Facilities supported by the Office of Science of the U.S.Department of Energy,under Contracts No.DE-AC02-05CH11231 and DE-AC02-06CH11357,respectivelyThe authors acknowledge the Texas Advanced Computing Center(TACC)at The University of Texas at Austin for providing access to Frontera,Lonestar6,and Texascale Days,which have contributed to the research results reported within this paper(http://www.tacc.utexas.edu)the Extreme Science and Engineering Discovery Environment(XSEDE)218 which is supported by National Science Foundation grant number ACI-1548562in particular Expanse at the San Diego Supercomputer Center through allocation TG-DMR180071.S.Packnowl-edges computational resources provided by the PRACE award granting access to Discoverer in SofiaTech,Bulgaria(OptoSpin project id.2020225411)by the Consortium desÉquipements de Calcul Intensif(CÉCI),funded by the FRS-FNRS under Grant No.2.5020.11the Walloon Region,as well as computational resources awarded on the Belgian share of the EuroHPC LUMI supercomputer.K.B.acknowledges the support of the U.S.Department of Energy,Office of Science,Office of Advanced Scientific Computing Research,Department of Energy Computational Science Graduate Fellowship under Award Number DE-SC0020347The authors wish to thank Zhenbang Dai,Nikolaus Kandolf,Viet-Anh Ha,and Amanda Wang for their contributions to the EPW project that are not discussed in this manuscriptJohn Cazes and Hang Liu at TACC for their support with the Characteristic Science Applications project,Paolo Giannozzi for his support with Quantum ESPRESSOStefano Baroni for fruitful discussions.
文摘EPW is an open-source software for ab initio calculations of electron–phonon interactions and related materials properties.The code combines density functional perturbation theory and maximally localized Wannier functions to efficiently compute electron–phonon coupling matrix elements,and to perform predictive calculations of temperature-dependent properties and phonon-assisted quantum processes in bulk solids and low-dimensional materials.Here,we report on significant developments in the code since 2016,namely:a transport module for the calculation of charge carrier mobility under electric and magnetic fields using the Boltzmann transport equation;a superconductivity module for calculations of phonon-mediated superconductors using the anisotropic multi-band Eliashberg theory;an optics module for calculations of phonon-assisted indirect transitions;a module for the calculation of small and large polarons without supercells;and a module for calculating band structure renormalization and temperature-dependent optical spectra using the special displacement method.For each capability,we outline the methodology and implementation and provide example calculations.
基金This work was supported by the State Key Project of Fundamental Research for Nanoscience and Nanotechnology (Nos. 2011CB932401, 2011CBA00500, and 2012CB224802), and the National Natural Science Foundation of China (Nos. 21221062, 21131004, and 21390393). The authors thank Electron Microscopy Laboratory of Peking University for the help with HRTEM analysis.
基金This work was supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA22050100),the National Natural Science Foundation of China(NSFC,41822604,41576104),the National Key Research and Development Program of China(2016YFC0302103)the Key Research Program of Frontier Sciences,of Chinese Academy of Sciences(QYZDB-SSW-DQC004)+2 种基金the NSFC-Shandong Joint Fund for Marine Science Research Centers(U1606401)the Young Taishan Scholars Program(tsqn201909158)the Laboratory for Marine Geology,Pilot National Laboratory for Marine Science and Technology(Qingdao)(MGQNLM-TD201904).Any additional data can be obtained from Xin Zhang.
文摘Electronic adjustment is one of the most commonly used strategies to improve the catalytic performance of heterogeneous catalysts. We prepared hexagonal ultrathin Pd nanosheets with edges modified by gold nanoparticles (Au@Pd nanosheets) using galvanic replacement method. By virtue of the electronic interactions between the Pd nanosheets and Au nanoparticles, the Au@Pd nanosheets exhibited excellent catalytic performances in the carbonylation of iodobenzene by carbon monoxide. The novel nanocomposites could be applied as model catalysts to explore electronic effects in catalysis.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China (Nos. 21521091, 21390393, U1463202, 21573119, and 21590792), the National Key Research and Development Program of China (No. 2016YFA0202801) and Fundamental Research Funds for the Central Universities (No. 2015RC070).
文摘An efficient, controllable, and facile two-step synthetic strategy to prepare graphene-based nanocomposites is proposed. A series of Fe3O4-decorated reduced graphene oxide (Fe3O4@RGO) nanocomposites incorporating Fe3O4 nanocrystals of various sizes were prepared by an ethanothermal method using graphene oxide (GO) and monodisperse Fe3O4 nanocrystals with diameters ranging from 4 to 10 nm. The morphologies and microstructures of the as-prepared composites were characterized by X-ray diffraction, Raman spectroscopy, nitrogen adsorption measurements, and transmission electron microscopy. The results show that GO can be reduced to graphene during the ethanothermal process, and that the Fe3O4 nanocrystals are well dispersed on the graphene sheets generated in the process. The analysis of the electrochemical properties of the Fe3O4@RGO materials shows that nanocomposites prepared with Fe3O4 nanocrystals of different sizes exhibit different electrochemical performances. Among all samples, FegO4@RGO prepared with Fe3O4 nanocrystals of 6 nm diameter possessed the highest specific capacitance of 481 F/g at 1 A/g, highlighting the excellent capability of this material. This work illustrates a promising route to develop graphene-based nanocomposite materials with a wide range of potential applications.