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1.
Artículo en Inglés | MEDLINE | ID: mdl-38728589

RESUMEN

The interfacial structure formed by Pt nanoparticles grown epitaxially on a SrTiO3 (001) surface by pulsed laser deposition was studied by X-ray standing-wave (XSW) excited core-level photoelectron emission. The XSW-generated 3D atomic map of the Pt and interfacial oxygens for the oxidized Pt/SrTiO3 interface differs significantly from that of the as-deposited interface. After oxidation, the Pt atoms shifted upward and their atomic occupation at fcc-like sites evolved as the oxidation temperature increased. Interfacial oxygen atoms were differentiated from bulk O atoms by the chemical shift in the binding energy of their 1s electrons. After oxidation, the interfacial oxygen atoms rearranged to form a TiO2 bilayer at the interface. These results provide a more complete description of the strong metal-support interaction process at the interface.

2.
Dalton Trans ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747712

RESUMEN

Birefringent materials with high optical anisotropy have been identified as a research hotspot owing to their significant scientific and technological significance in modern optoelectronics for manipulating light polarization. Researchers studying borate systems have discovered that adding π-conjugated units placed in parallel can significantly increase the birefringence of crystalline solids; some examples include [BO3] units, [B2O5] units, and [B3O6] units. However, there are not many borates with strictly parallel configurations of π-conjugated [B2O5] units. In this study, a new bimetallic borate Sr2Cd4(B2O5)3 with near-parallel arrangement of π-conjugated [B2O5] units was discovered. Sr2Cd4(B2O5)3 possesses the maximum number density of [B2O5] units, shortest dihedral angle of [B2O5] units (between the two [BO3]), and largest degree of [CdO6] octahedral distortion among all the currently known Sr-Cd-B-O tetragonal system borates, making it demonstrate a large birefringence of 0.102 at 532 nm. Theoretical analysis proves that π-conjugated [B2O5] anions are the primary source of the large birefringence of Sr2Cd4(B2O5)3.

3.
Biol Reprod ; 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38401166

RESUMEN

OBJECTIVE: This study aimed to explore the specific pathways by which HOX transcript antisense intergenic RNA (HOTAIR) contributes to the pathogenesis of unexplained recurrent spontaneous abortion (URSA). METHODS: Real-time quantitative PCR (RT-qPCR) was employed to assess the differential expression levels of HOTAIR in chorionic villi tissues from URSA patients and women with voluntarily terminated pregnancies. HTR-8/SVneo served as a cellular model. Knockdown and overexpression of HOTAIR in the cells were achieved through siRNA transfection and pcDNA3.1 transfection, respectively. Cell viability, migration, and invasion were evaluated using cell counting kit-8 (CCK-8), scratch, and Transwell assays, respectively. The interaction among the HOTAIR/miR-1277-5p/fibrillin 2 (FBN2) axis was predicted through bioinformatics analysis and confirmed through in vitro experiments. Furthermore, the regulatory effects of the HOTAIR/miR-1277-5p/FBN2 signaling axis on cellular behaviors were validated in HTR-8/SVneo cells. RESULTS: We found that HOTAIR was downregulated in chorionic villi tissues from URSA patients. Overexpression of HOTAIR significantly enhanced the viability, migration, and invasion of HTR-8/SVneo cells, while knockdown of HOTAIR had the opposite effects. We further confirmed the regulatory effect of the HOTAIR/miR-1277-5p/FBN2 signaling axis in URSA. Specifically, HOTAIR and FBN2 were found to reduce the risk of URSA by enhancing cell viability, migration, and invasion, whereas miR-1277-5p exerted the opposite effects. CONCLUSION: HOTAIR promotes URSA development by targeting inhibition of miR-1277-5p/FBN2 axis.

4.
Commun Biol ; 6(1): 1125, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37935958

RESUMEN

Nervonic acid benefits the treatment of neurological diseases and the health of brain. In this study, we employed the oleaginous yeast Yarrowia lipolytica to overproduce nervonic acid oil by systematic metabolic engineering. First, the production of nervonic acid was dramatically improved by iterative expression of the genes ecoding ß-ketoacyl-CoA synthase CgKCS, fatty acid elongase gELOVL6 and desaturase MaOLE2. Second, the biosynthesis of both nervonic acid and lipids were further enhanced by expression of glycerol-3-phosphate acyltransferases and diacylglycerol acyltransferases from Malania oleifera in endoplasmic reticulum (ER). Third, overexpression of a newly identified ER structure regulator gene YlINO2 led to a 39.3% increase in lipid production. Fourth, disruption of the AMP-activated S/T protein kinase gene SNF1 increased the ratio of nervonic acid to lignoceric acid by 61.6%. Next, pilot-scale fermentation using the strain YLNA9 exhibited a lipid titer of 96.7 g/L and a nervonic acid titer of 17.3 g/L (17.9% of total fatty acids), the highest reported titer to date. Finally, a proof-of-concept purification and separation of nervonic acid were performed and the purity of it reached 98.7%. This study suggested that oleaginous yeasts are attractive hosts for the cost-efficient production of nervonic acid and possibly other very long-chain fatty acids (VLCFAs).


Asunto(s)
Yarrowia , Yarrowia/genética , Ingeniería Metabólica , Ácidos Grasos/metabolismo , Aciltransferasas/metabolismo
5.
Front Immunol ; 14: 1049536, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36793712

RESUMEN

Background: Sepsis is organ dysfunction due to the host's deleterious response to infection, and the kidneys are one of the organs damaged in common sepsis. Sepsis-associated acute kidney injury (SA-AKI) increases the mortality in patients with sepsis. Although a substantial volume of research has improved the prevention and treatment of the disease, SA-SKI is still a significant clinical concern. Purpose: Aimed to use weighted gene co-expression network analysis (WGCNA) and immunoinfiltration analysis to study SA-AKI-related diagnostic markers and potential therapeutic targets. Methods: Immunoinfiltration analysis was performed on SA-AKI expression datasets from the Gene Expression Synthesis (GEO) database. A weighted gene co-expression network analysis (WGCNA) analysis was performed on immune invasion scores as trait data, and modules associated with immune cells of interest were identified as hub modules. Screening hub geneset in the hub module using protein-protein interaction (PPI) network analysis. The hub gene was identified as a target by intersecting with significantly different genes screened by differential expression analysis and validated using two external datasets. Finally, the correlation between the target gene, SA-AKI, and immune cells was verified experimentally. Results: Green modules associated with monocytes were identified using WGCNA and immune infiltration analysis. Differential expression analysis and PPI network analysis identified two hub genes (AFM and GSTA1). Further validation using additional AKI datasets GSE30718 and GSE44925 showed that AFM was significantly downregulated in AKI samples and correlated with the development of AKI. The correlation analysis of hub genes and immune cells showed that AFM was significantly associated with monocyte infiltration and hence, selected as a critical gene. In addition, Gene single-enrichment analysis (GSEA) and PPI analyses results showed that AFM was significantly related to the occurrence and development of SA-AKI. Conclusions: AFM is inversely correlated with the recruitment of monocytes and the release of various inflammatory factors in the kidneys of AKI. AFM can be a potential biomarker and therapeutic target for monocyte infiltration in sepsis-related AKI.


Asunto(s)
Lesión Renal Aguda , Sepsis , Humanos , Lesión Renal Aguda/genética , Bases de Datos Factuales , Riñón , Monocitos , Sepsis/complicaciones
6.
Biomed Pharmacother ; 155: 113772, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36271554

RESUMEN

The objective of this study was to explore an innovative sustained release technology and design a new microporous resin-based polymer device (RPD) for controlled release of glipizide (GZ). Photocurable resin was applied to prepare the resin layer to control GZ release. The impact of formulation parameters consisting of the type and amount of pore formers and pH modifiers, photocurable curing time as well as the weight of resin layer on GZ release were examined. The GZ-RPD was fabricated applying 24 mg of resin layer with PEG400 (100 % of the resin weight) as pore former and 10 mg of Na2CO3 as pH modifier. Scanning electron microscopy (SEM) demonstrated resin particles presenting a porous structure constituted the resin layer. The GZ-RPD possessed prolonged Tmax and reduced Cmax relative to commercial tablets. The relative bioavailability of the RPDs as well as commercial tablets was 93.65 % since the AUC0-24 h were 6111.05 ± 238.89 ng·h/mL and 6525.09 ± 760.59 ng h/mL, respectively. The release mechanism of the GZ-RPD was discussed. This paper provided an innovative concept to produce controlled GZ release oral formulation fabricated by photocurable resin, which demonstrated both excellent in vitro release and in vivo pharmacokinetics.


Asunto(s)
Glipizida , Polímeros , Glipizida/química , Glipizida/farmacocinética , Preparaciones de Acción Retardada/química , Comprimidos , Excipientes/química
7.
Sci Total Environ ; 843: 157042, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35777558

RESUMEN

With the rapid development of the nano-material and chemical industry, more and more microplastic (MP) and nano-material were discharged into the environment. In this study, a two-dimensional (2D) surface of Extended Darjaguin-Landau-Verwe-Overbeek (XDLVO) is proposed to quantitatively investigate the effect of polyamide (PA) on the transport of graphene oxide (GO) in porous media. The influences of mass fraction of PA, flow rate, GO concentration, ionic type and strength on the migration of GO in saturated porous media are investigated by column experiments and numerical models. The two-dimensional (2D) surfaces of XDLVO interaction energy between GO and GO, GO and QS, GO and PA, are firstly calculated to analyze the transport of GO in saturated porous media. Experimental results suggest the mobility of GO is enhanced when flow velocity and initial concentration of GO are increased. However, the mobility of GO is inhibited when the mass fraction of PA and ionic strength are increased. More important, the inhibitory effect of divalent cations on GO migration is stronger than that of monovalent cations. Simultaneously, XDLVO results suggest that ionic types and strengths are important factors affecting the mobility of GO in porous media, and the critical ionic strength is observed from the continuous variation of the secondary minimum trap of XDLVO interaction energy. Model results show that there is a linear relationship between the logarithm of the secondary minimum trap of XDLVO interaction energy and the parameters related to GO mobility, which suggests XDLVO energy surface has an important application significance in the accurate quantification of GO mobility in porous media. These findings contribute to GO transport affected by microplastic in porous media, thus laying a significant foundation for the environmental risk and contamination remediation.


Asunto(s)
Microplásticos , Nylons , Grafito , Concentración Osmolar , Óxidos , Plásticos , Porosidad
8.
Front Med (Lausanne) ; 9: 736006, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35647002

RESUMEN

Chronic kidney disease (CKD) is defined by persistent urine aberrations, structural abnormalities, or impaired excretory renal function. Diabetes is the leading cause of CKD. Their common pathological manifestation is renal fibrosis. Approximately half of all patients with type 2 diabetes and one-third with type 1 diabetes will develop CKD. However, renal fibrosis mechanisms are still poorly understood, especially post-transcriptional and epigenetic regulation. And an unmet need remains for innovative treatment strategies for preventing, arresting, treating, and reversing diabetic kidney disease (DKD). People believe that protein methylation, including histone and non-histone, is an essential type of post-translational modification (PTM). However, prevalent reviews mainly focus on the causes such as DNA methylation. This review will take insights into the protein part. Furthermore, by emphasizing the close relationship between protein methylation and DKD, we will summarize the clinical research status and foresee the application prospect of protein methyltransferase (PMT) inhibitors in DKD treatment. In a nutshell, our review will contribute to a more profound understanding of DKD's molecular mechanism and inspire people to dig into this field.

9.
J Phys Chem Lett ; : 5304-5309, 2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35675154

RESUMEN

Supported molybdenum oxide (MoOx) plays an important role in catalytic transformations from alcohol dehydrogenation to transesterification. During these reactions, molybdenum and oxygen surface species undergo structural and chemical changes. A detailed, chemical-state specific, atomic-scale structural analysis of the catalyst under redox conditions is important for improving catalytic properties. In this study, a monolayer of Mo grown on α-TiO2(110) by atomic-layer deposition is analyzed by X-ray standing wave (XSW) excited X-ray photoelectron spectroscopy (XPS). The chemical shifts for Mo 2p3/2 and O 1s peaks are used to distinguish Mo6+ from Mo4+ and surface O from bulk O. Excitation of XPS by XSW allows pinpointing the location of these surface species relative to the underlying substrate lattice. Measured 3D composite atomic density maps for the oxidized and reduced interfaces compare well with our density functional theory models and collectively create a unique view of the redox-driven dynamics for this complex catalytic structure.

10.
Phys Rev Lett ; 128(20): 206801, 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35657902

RESUMEN

X-ray standing-wave (XSW) excited photoelectron emission was used to measure the site-specific valence band (VB) for ½ monolayer (ML) Pt grown on a SrTiO_{3} (001) surface. The XSW induced modulations in the core level (CL), and VB photoemission from the surface and substrate atoms were monitored for three hkl substrate Bragg reflections. The XSW CL analysis shows the Pt to have a face-centered-cubic-like cube-on-cube epitaxy with the substrate. The XSW VB information compares well to a density functional theory calculated projected density of states from the surface and substrate atoms. Overall, this Letter represents a novel method for determining the contribution to the density of states by valence electrons from specific atomic surface sites.

11.
Front Physiol ; 13: 830924, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35464083

RESUMEN

Sepsis is a systemic inflammatory response caused by a severe infection that leads to multiple organ damage, including acute kidney injury (AKI). In intensive care units (ICU), the morbidity and mortality associated with sepsis-associated AKI (SA-AKI) are gradually increasing due to lack of effective and early detection, as well as proper treatment. Non-coding RNAs (ncRNAs) exert a regulatory function in gene transcription, RNA processing, post-transcriptional translation, and epigenetic regulation of gene expression. Evidence indicated that miRNAs are involved in inflammation and programmed cell death during the development of sepsis-associated AKI (SA-AKI). Moreover, lncRNAs and circRNAs appear to be an essential regulatory mechanism in SA-AKI. In this review, we summarized the molecular mechanism of ncRNAs in SA-AKI and discussed their potential in clinical diagnosis and treatment.

12.
Dalton Trans ; 51(4): 1481-1488, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-34989372

RESUMEN

The exploration of A-Mo-P-O (A = Rb, Cs) systems has allowed several new Mo(V) phosphates, Rb2MoP2O9, Rb6Mo2P4O19 and Cs6Mo2P4O19, to be synthesized through the spontaneous nucleation method. Single-crystal X-ray diffraction analysis reveals that the identical stoichiometry compounds Rb2MoP2O9 and Cs2MoP2O9 belong to different space groups C2/c and Pbca, respectively. Both compounds consist of dissimilar 1D [Mo-O-P]∞ chains with different repeated building units, while monovalent cations fill in spaces to form 3D structures. However, Rb6Mo2P4O19 and Cs6Mo2P4O19 are isostructural and crystallize in the same space group of P21/c. They exhibit a 3D framework structure with 0D Mo2O5O6P4O8 groups, which are separated by Rb/Cs atoms. Interestingly, structural relationships between the different monophosphates of the A-Mo-P-O (A = Rb, Cs) systems are presented in which distinct polyanionic configurations appear owing to the A/P ratios, as well as the size of the univalent cations. Further, detailed structural comparisons, optical properties and theoretical calculations are also discussed.

13.
Crit Rev Food Sci Nutr ; 62(10): 2627-2640, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33320702

RESUMEN

Due to special cavity structure, cyclodextrin can form inclusion complex with a large number of compounds, which can be widely used in food industry, such as enhancing antibacterial activity, extending the storage period of food, increasing the solubility of food ingredients, removing cholesterol in food and so on. In this paper, the formation mechanism, classification and properties of cyclodextrin inclusion complex were reviewed, and the applications of cyclodextrin and its derivatives in food industry were discussed.


Asunto(s)
Ciclodextrinas , Antioxidantes/química , Ciclodextrinas/química , Industria de Alimentos , Solubilidad
14.
ACS Mater Au ; 2(2): 110-116, 2022 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36855761

RESUMEN

The crystal structure, which intrinsically affects the properties of solids, is determined by the constituent elements and composition of solids. Therefore, it cannot be easily controlled beyond the phase diagram because of thermodynamic limitations. Here, we demonstrate the first example of controlling the crystal structures of a solid-solution nanoparticle (NP) entirely without changing its composition and size. We synthesized face-centered cubic (fcc) or hexagonal close-packed (hcp) structured Pd x Ru1-x NPs (x = 0.4, 0.5, and 0.6), although they cannot be synthesized as bulk materials. Crystal-structure control greatly improves the catalytic properties; that is, the hcp-Pd x Ru1-x NPs exceed their fcc counterparts toward the oxygen evolution reaction (OER) in corrosive acid. These NPs only require an overpotential (η) of 200 mV at 10 mA cm-2, can maintain the activity for more than 20 h, greatly outperforming the fcc-Pd0.4Ru0.6 NPs (η = 280 mV, 9 min), and are among the most efficient OER catalysts reported. Synchrotron X-ray-based spectroscopy, atomic-resolution electron microscopy, and density functional theory (DFT) calculations suggest that the enhanced OER performance of hcp-PdRu originates from the high stability against oxidative dissolution.

15.
J Am Chem Soc ; 143(43): 17937-17941, 2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34672550

RESUMEN

During redox reactions, oxide-supported catalytic systems undergo structural and chemical changes. Improving subsequent catalytic properties requires an understanding of the atomic-scale structure with chemical state specificity under reaction conditions. For the case of 1/2 monolayer vanadia on α-TiO2(110), we use X-ray standing wave (XSW) excited X-ray photoelectron spectroscopy to follow the redox induced atomic positional and chemical state changes of this interface. While the resulting XSW 3D composite atomic maps include the Ti and O substrate atoms and V surface atoms, our focus in this report is on the previously unseen surface oxygen species with comparison to density functional theory predictions.

16.
Eur J Pharm Biopharm ; 163: 102-108, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33819628

RESUMEN

The aim of this study was to formulate osmotic pump capsules (OPCs) to control the release of nifedipine (NP). NP solid dispersion was prepared by solvent evaporation method. The prepared mixture of NP solid dispersion and various excipients were filled into the commercial HPMC hard capsule shells and then coated with cellulose acetate (CA) solution to form NP-OPC. The CA coating solution consisted of CA as semi-permeable membrane, and Poloxamer 188 as pore formers. The impact of addition agents, citric acid and pore formers on in vitro drug release were investigated. Furthermore, the study has highlighted the impact of paddle speed and the pH value of release media, on the release and compared the release with the commercial controlled release tablets. The in vitro drug release study indicated that drug release could reach 95% in 24 h with optimal formulation, and interestingly model fitting showed that the drug release behavior was closely followed to zero-order release kinetics. The pharmacokinetic studies were performed in rabbits with commercial controlled release tablets as reference, both preparations showed a sustained release effect. Compared with traditional preparation methods of OPCs, the new preparation process was simplified without the operation of laser drilling and the sealing process of capsule body and cap, which improved the feasibility of industrial production.


Asunto(s)
Excipientes/química , Nifedipino/farmacocinética , Poloxámero/química , Animales , Cápsulas , Celulosa/análogos & derivados , Celulosa/química , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/farmacocinética , Evaluación Preclínica de Medicamentos , Liberación de Fármacos , Concentración de Iones de Hidrógeno , Nifedipino/administración & dosificación , Presión Osmótica , Conejos , Solubilidad , Comprimidos
17.
Adv Mater ; 33(16): e2005206, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33751709

RESUMEN

Since 1970, people have been making every endeavor to reduce toxic emissions from automobiles. After the development of a three-way catalyst (TWC) that concurrently converts three harmful gases, carbon monoxide (CO), hydrocarbons (HCs), and nitrogen oxides (NOx ), Rh became an essential element in automobile technology because only Rh works efficiently for catalytic NOx reduction. However, due to the sharp price spike in 2007, numerous efforts have been made to replace Rh in TWCs. Nevertheless, Rh remains irreplaceable, and now, the price of Rh is increasing significantly again. Here, it is demonstrated that PdRuM ternary solid-solution alloy nanoparticles (NPs) exhibit highly durable and active TWC performance, which will result in a significant reduction in catalyst cost compared to Rh. This work provides insights into the design of highly durable and efficient functional alloy NPs, guiding how to best take advantage of the configurational entropy in addition to the mixing enthalpy.

18.
Nat Commun ; 12(1): 1145, 2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33594054

RESUMEN

Water is the only available fossil-free source of hydrogen. Splitting water electrochemically is among the most used techniques, however, it accounts for only 4% of global hydrogen production. One of the reasons is the high cost and low performance of catalysts promoting the oxygen evolution reaction (OER). Here, we report a highly efficient catalyst in acid, that is, solid-solution Ru‒Ir nanosized-coral (RuIr-NC) consisting of 3 nm-thick sheets with only 6 at.% Ir. Among OER catalysts, RuIr-NC shows the highest intrinsic activity and stability. A home-made overall water splitting cell using RuIr-NC as both electrodes can reach 10 mA cm-2geo at 1.485 V for 120 h without noticeable degradation, which outperforms known cells. Operando spectroscopy and atomic-resolution electron microscopy indicate that the high-performance results from the ability of the preferentially exposed {0001} facets to resist the formation of dissolvable metal oxides and to transform ephemeral Ru into a long-lived catalyst.

19.
Front Bioeng Biotechnol ; 8: 583318, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33251198

RESUMEN

The pathogenesis of renal fibrosis (RF) is not well understood. Here, we performed an integrative database analysis of miRNAs and mRNAs to discover the major regulatory pathway in RF. Putative miRNAs and mRNAs involved in RF in unilateral ureteral obstruction (UUO) model mice were extracted and analyzed using the Gene Expression Omnibus (GEO) database. The bioinformatics analysis suggested that Ptch1 expression is regulated by miR-342-5p and FoxO3. Then real-time PCR, Western blot, Fluorescence in situ hybridization were done to confirm the hypothesis. Sixty-three differentially expressed miRNAs (DE-miRNAs) in GSE118340, 141 DE-miRNAs in GSE42716, and 183 DE-mRNAs in GSE69101 were identified. Various bioinformatic analyses revealed miR-342-5p as a strong candidate regulator in RF. We also predicted that miR-342-5p targets Ptch1 and that FoxO3 is the transcription factor of Ptch1. We also observed that TGF-ß1 upregulated the expression of miR-342-5p and inhibited the expression of FoxO3 and Ptch1 in TCMK-1 cells. Furthermore, downregulation of miR-342-5p reversed the inhibitory effect of TGF-ß1 on the expression of Ptch1 in TCMK-1 cells, while downregulation of FoxO3 promoted the inhibitory effect of TGF-ß1 on the expression of Ptch1. Additionally, downregulation of Ptch1 increased TGF-ß1-induced autophagy, as evidenced by an increase in the number of GFP-LC3 puncta and the increased protein expression of SOSTM1/p62 and LC3II/LC3I. Our findings showed that Ptch1 expression is negatively regulated by miR-342-5p and positively regulated by FoxO3, and downregulation of Ptch1 induced autophagy in TGF-ß1-stimulated TCMK-1 cells. These findings will further our understanding of the molecular mechanisms of RF and provide useful novel therapeutic targets for RF.

20.
Nat Commun ; 11(1): 5197, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33060588

RESUMEN

A solid with larger sound speeds usually exhibits higher lattice thermal conductivity. Here, we report an exception that CuP2 has a quite large mean sound speed of 4155 m s-1, comparable to GaAs, but single crystals show very low lattice thermal conductivity of about 4 W m-1 K-1 at room temperature, one order of magnitude smaller than GaAs. To understand such a puzzling thermal transport behavior, we have thoroughly investigated the atomic structures and lattice dynamics by combining neutron scattering techniques with first-principles simulations. This compound crystallizes in a layered structure where Cu atoms forming dimers are sandwiched in between P atomic networks. In this work, we reveal that Cu atomic dimers vibrate as a rattling mode with frequency around 11 meV, which is manifested to be remarkably anharmonic and strongly scatters acoustic phonons to achieve the low lattice thermal conductivity.

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