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1.
Poult Sci ; 103(10): 104056, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-39094498

RESUMEN

Wooden breast (WB) is a myopathy mainly affecting pectoralis major (PM) muscle in modern commercial broiler chickens, causing enormous economic losses in the poultry industry. Recent studies have observed hepatic and PM muscle injury in broilers affected by WB, but the relationships between WB and the 2 tissues are mostly unclear. In the current study, the RNA-seq raw data of PM muscle and liver were downloaded from GSE144000, and we constructed the gene coexpression networks of PM muscle and liver to explore the relationships between WB and the 2 tissues using the weighted gene coexpression network analysis (WGCNA) method. Six and 2 gene coexpression modules were significantly correlated with WB in the PM muscle and liver networks, respectively. TGF-beta signaling, Toll-like receptor signaling and mTOR signaling pathways were significantly enriched in the genes within the 6 gene modules of PM muscle network. Meanwhile, mTOR signaling pathway was significantly enriched in the genes within the 2 gene modules of liver network. In the consensus gene coexpression network across the 2 tissues, salmon module (r = -0.5 and p = 0.05) was significantly negatively correlated with WB, in which Toll-like receptor signaling, apoptosis, and autophagy pathways were significantly enriched. The genes related with the 3 pathways, myeloid differentiation primary response 88 (MYD88), interferon regulatory factor 7 (IRF7), mitogen-activated protein kinase 14 (MAPK14), FBJ murine osteosarcoma viral oncogene homolog (FOS), jun proto-oncogene (JUN), caspase-10, unc-51 like autophagy activating kinase 2 (ULK2) and serine/threonine kinase 11 (LKB1), were identified in salmon module. In this current study, we found that the signaling pathways related with cell inflammation, apoptosis and autophagy might influence WB across 2 tissues in broilers.

2.
Small ; : e2402317, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38988143

RESUMEN

Here, the poly (l-lactic acid) (PLLA) membrane with multi-structured networks (MSN) is successfully prepared by electrospinning technology for the first time. It is composed of micron-sized ribbon-structured fibers and ultrafine nanofibers with a diameter of tens of nanometers, and they are connected to form the new network structure. Thanks to the special fiber morphology and structure, the interception and electrostatic adsorption ability for against atmospheric particulate matter (PM) are significantly enhanced, and the resistance to airflow is reduced due to the "slip effect" caused by ultrafine nanofibers. The PLLA MSN membrane shows excellent filtration performance with ultra-high filtration efficiency (>99.9% for PM2.5 and >99.5% for PM0.3) and ultra-low pressure drop (≈20 Pa). It has demonstrated filtration performance that even exceeds current non-biodegradable polymer materials, laying the foundation for future applications of biodegradable PLLA in the field of air filtration. In addition, this new structure also provides a new idea for optimizing the performance of other polymer materials.

3.
Nanomaterials (Basel) ; 14(11)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38869562

RESUMEN

The reduced graphene oxide (rGO) exhibits outstanding electrical conductivity and a high specific surface area, making it a promising material for various applications. Fe2O3 is highly desirable due to its significant theoretical capacity and cost-effectiveness, high abundance, and environmental friendliness. However, the performance of these r-GO/Fe2O3 composite electrodes still needs to be further improved, especially in terms of cycle stability. The composite of Fe2O3 anchored on N-doped graphene with inside micro-channels (Fe2O3@N-GIMC) was used to be efficiently prepared. Because the inside channels can furnish extra transmission pathways and absorption websites and the interconnected structure can efficaciously forestall pulverization and aggregation of electrode materials. In addition, N doping is also beneficial to improve its electrochemical performance. Thus, it demonstrates exceptional sodium storage characteristics, including notable electrochemical activity, impressive initial Coulombic efficiency, and favorable rate performance. The optimized Fe2O3@N-GIMC indicates outstanding discharge capacity (573.5 mAh g-1 at 1 A g-1), significant rate performance (333.6 mAh g-1 at 8 A g-1), and stable long-term cycle durability (308.9 mAh g-1 after 1000 cycles at 1 A g-1, 200.8 mAh g-1 after 4000 cycles at 1 A g-1) as a sodium-ion battery anode. This presents a new approach for preparing graphene-based high-functional composites and lays a stable basis for further expanding its application field.

4.
Nanomaterials (Basel) ; 14(4)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38392734

RESUMEN

Herein, the preparation process, morphology, structure, and magnetic properties of La1.85Sr0.15CuO4 (LSCO) cobweb-like nanofibers are reported. LSCO nanofibers with a regular grain size distribution are successfully prepared via electrospinning, followed by calcination. We conducted morphology analysis and elemental distribution using electron microscopy and energy-dispersive X-ray spectroscopy (EDS), respectively. Additionally, magnetic property testing was performed using a vibrating sample magnetometer (VSM) to confirm the superconducting properties of the samples. Interestingly, our samples exhibited a superconducting transition temperature, Tc, of 25.21 K, which showed some disparity compared to similar works. Furthermore, we observed a ferromagnetic response at low temperatures in the superconducting nanofibers. We attribute these phenomena to the effects generated by surface states of nanoscale superconducting materials.

5.
Research (Wash D C) ; 2022: 9819373, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35707049

RESUMEN

Moiré pattern in twisted multilayers (tMLs) induces many emergent phenomena by subtle variation of atomic registry to modulate quasiparticles and their interactions, such as superconductivity, moiré excitons, and moiré phonons. The periodic superlattice potential introduced by moiré pattern also underlies patterned interlayer coupling at the interface of tMLs. Although this arising patterned interfacial coupling is much weaker than in-plane atomic interactions, it is crucial in moiré systems, as captured by the renormalized interlayer phonons in twisted bilayer transitional metal dichalcogenides. Here, we determine the quantitative relationship between the lattice dynamics of intralayer out-of-plane optical (ZO) phonons and patterned interfacial coupling in multilayer graphene moiré superlattices (MLG-MS) by the proposed perturbation model, which is previously challenging for MLGs due to their out-of-phase displacements of adjacent atoms in one atomic plane. We unveil that patterned interfacial coupling introduces profound modulations on Davydov components of nonfolded ZO phonon that are localized within the AB-stacked constituents, while the coupling results in layer-extended vibrations with symmetry of moiré pattern for moiré ZO phonons. Our work brings further degrees of freedom to engineer moiré physics according to the modulations imprinted on the phonon frequency and wavefunction.

6.
J Phys Condens Matter ; 34(4)2021 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-34474403

RESUMEN

Superconducting nanofibers have attracted much attention in basic researches and practical applications due to their unique physical properties such as broad phase transition temperature, excellent heat conductivity, and high critical current density, etc. Electrospinning, as a common method to prepare nanofibers, also has many applications for the preparation of superconducting nanofibers. However, a few of the new methods to fabricate superconducting nanofibers via electrospinning still need further investigations. This review firstly introduces several potential electrospinning methods to obtain superconducting nanofibers, then proceeds to summarize the recent progress in the field of electrospun superconducting materials. The preparation process, difficulties and problems, physical properties of the superconducting nanofibers or nanonetworks (such as superconducting transition temperature, critical current density, critical magnetic field strength, fiber morphology, and structure, etc), theoretical analysis of the properties, and the techniques to improve the performance are also reviewed. In addition, some suggestions and prospects for the development and applications of electrospun superconducting materials in the future are discussed.

7.
RSC Adv ; 10(14): 8055-8065, 2020 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35497838

RESUMEN

The effect of Fe, Co and Ni promoters on supported MoS2 catalysts for hydrogenation of nitroarenes were systematically investigated via experiment, characterization and DFT calculation. It was found that the addition of promoters remarkably improved the reaction activity in a sequence of Ni > Co > Fe > Mo. Meanwhile Ni promoted catalyst with the best performance showed good recyclability and chemoselectivity for a wide substrate scope. The characterization results revealed that the addition of promoters decreased the interaction between Mo and support and facilitated the reductive sulfidation of Mo species to produce more coordinated unsaturated sites (CUS). DFT calculations showed that the addition of promoters increased the formation of CUS, and enhanced the adsorption of hydrogen. The influence degree of promoters followed the sequence Ni > Co > Fe > Mo, which was consistent with those of the activities. Nitrobenzene hydrogenation and hydrogen activation occurred at the S and Mo edge, respectively. The adsorbed hydrogen diffused from the Mo edge to the S edge to participate in the hydrogenation reaction. Mechanism investigation showed that the main reason for increased activity by the addition of promoters was the increase of amounts of CUS and the secondary reason was the augmentation of intrinsic activity of CUS. The present studies give a new understanding for promoter modified MoS2 catalysts applied for hydrogenation of nitroarenes.

8.
ACS Appl Mater Interfaces ; 11(11): 10810-10817, 2019 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-30807085

RESUMEN

Because of its notable electrical and mechanical properties, the highly conductive graphene paper has great potential applications in future flexible electronics. In this study, we report a simple and effective method to prepare vertically aligned graphene oxide papers from graphene oxide suspensions by an improved electrospray deposition technique with a moving stage, which is controlled by computer. Then, the flexible reduced graphene oxide papers are successfully synthesized after reduction by using hydroiodic acid. The obtained reduced graphene oxide paper has an electrical conductivity as high as 6180 S/m, which is more than one and a half times of the reduced graphene oxide paper film, which was fabricated by using the electrospray deposition technique without the moving stage. The experimental results approved for the first time that the degree of alignment of reduced graphene oxide sheets can affect the conductivity of the reduced graphene oxide papers. Further electrochemical measurements for a symmetrical supercapacitor device based on the prepared reduced graphene oxide paper indicate that it has great capacitive performance and electrochemical stability. It exhibited relatively high specific capacitance (174 F·g-1) at a current density of 1 A·g-1 in 6 M KOH aqueous solution, and its capacitance can retain approximately 86% after 1000 cycles. In addition, patterned freestanding reduced graphene oxide papers, which have potential applications in many fields such as stretchable electronics and wearable devices, also can be fabricated by using this method.

9.
Gene ; 646: 74-82, 2018 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-29289610

RESUMEN

It is known that the male hypogonadism plays an important role in regulating adipose metabolism. In the present study, fifteen pairs of full male sibs were divided into a castrated group and an intact group with a paired experiment design. The pigs were slaughtered at an age of 175days. The carcass characteristics and fat deposit of the studied animal were measured, and the hormone and serum lipid levels of the peripheral blood samples were determined, and the differentially expressed genes of the back fat between the two groups were screened with porcine genome array. Our results showed that the absence of male gonadal steroids attributed to castration significantly raised the serum lipid levels and increased fat accumulation in the pigs. A total of 225 differentially expressed genes were identified between the boars and barrows and 135 of them were upregulated. The analysis of Gene Ontology categories and KEGG pathway indicated that these differentially expressed genes were mainly involved in metabolism of lipid, carbohydrate, amino acid, xenobiotics biodegradation, and immune diseases pathways. Our results indicated that there were higher capacity of fatty acid of synthesis, enhanced uptaking capacity of fatty acids and cholesterol, inhibited lipolysis, and enhanced carbohydrate metabolism in the adipose tissue of barrows compared to boars. The findings of the present study provide new insight into the mechanisms of adipose metabolism induced by hormone deficiency.


Asunto(s)
Tejido Adiposo/metabolismo , Perfilación de la Expresión Génica/métodos , Hormonas Esteroides Gonadales/deficiencia , Lípidos/sangre , Animales , Composición Corporal , Hormonas Esteroides Gonadales/sangre , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Transducción de Señal , Porcinos , Transcriptoma , Regulación hacia Arriba
10.
RSC Adv ; 8(2): 1078-1082, 2018 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-35538963

RESUMEN

Stretchable sensors, as the important components of flexible electronic devices, have achieved progress in a variety of applications for monitoring physical or environmental conditions, such as sound, temperature, vibration, and pressure. However, it still remains a challenge to fabricate high performance stretchable humidity sensors. Herein, we present a novel stretchable humidity sensor, which was fabricated based on an ultrastretchable polyaniline composite fiber. Because of the composite fiber with a "twining spring" configuration (cotton fibers twining spirally around a polyurethane fiber) it maintains a stable electrical conductivity up to a strain of 200%. In addition, the conductivity of the composite fiber remains perfectly stable after 5000 cyclic stretching events of 200% strain. Incorporating the humidity sensitive properties of nanostructured polyaniline, the stretchable humidity sensor based on the composite fiber effectively maintains its humidity sensitivity at different elongations.

11.
Poult Sci ; 97(2): 397-402, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29140467

RESUMEN

Single-step genomic prediction method has been proposed to improve the accuracy of genomic prediction by incorporating information of both genotyped and ungenotyped animals. The objective of this study is to compare the prediction performance of single-step model with a 2-step models and the pedigree-based models in a nuclear population of layers. A total of 1,344 chickens across 4 generations were genotyped by a 600 K SNP chip. Four traits were analyzed, i.e., body weight at 28 wk (BW28), egg weight at 28 wk (EW28), laying rate at 38 wk (LR38), and Haugh unit at 36 wk (HU36). In predicting offsprings, individuals from generation 1 to 3 were used as training data and females from generation 4 were used as validation set. The accuracies of predicted breeding values by pedigree BLUP (PBLUP), genomic BLUP (GBLUP), SSGBLUP and single-step blending (SSBlending) were compared for both genotyped and ungenotyped individuals. For genotyped females, GBLUP performed no better than PBLUP because of the small size of training data, while the 2 single-step models predicted more accurately than the PBLUP model. The average predictive ability of SSGBLUP and SSBlending were 16.0% and 10.8% higher than the PBLUP model across traits, respectively. Furthermore, the predictive abilities for ungenotyped individuals were also enhanced. The average improvements of prediction abilities were 5.9% and 1.5% for SSGBLUP and SSBlending model, respectively. It was concluded that single-step models, especially the SSGBLUP model, can yield more accurate prediction of genetic merits and are preferable for practical implementation of genomic selection in layers.


Asunto(s)
Crianza de Animales Domésticos/economía , Pollos/genética , Genómica/métodos , Modelos Genéticos , Animales , Cruzamiento , Femenino
12.
Opt Express ; 25(13): 14238-14246, 2017 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-28789009

RESUMEN

A variety of up-and-coming applications of piezoluminescence in artificial skins, structural health diagnosis, and mechano-driven lightings and displays recently have triggered an intense research effort to design and develop new piezoluminescent materials. In this work, we deduced and verified an efficient piezoluminescence in ferroelectric Ca3Ti2O7:Pr3+ long-persistent phosphor, in view of three fundamental elements forming piezoluminescence - piezoelectricity, luminescent centers and carrier traps. Under the stimulation of mechanical actions including compression and friction, Ca3Ti2O7:Pr3+ shows an intense red emission from 1D2-3H4 transition of Pr3+. On the basis of investigations on structural and optical characteristics especially photoluminescence, persistent luminescence and thermoluminescence, we finally proposed a possible piezoluminescent mechanism in Ca3Ti2O7:Pr3+. Our research is expected to expand the horizon of existing piezoluminescent materials, accelerating the development and application of new materials.

13.
Chemphyschem ; 18(3): 269-273, 2017 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-27902871

RESUMEN

Self-activated phosphors are capable of generating optical emissions from the internal ion groups of host lattice before externally introducing luminescent ions. However, numerous self-activated phosphors only show luminescence at low temperature due to the thermally activated energy migration among ion groups at room temperature, severely confining their application conditions. In this letter, we propose a strategy to converting the low-temperature luminescence to a room-temperature one through changing the synthesis conditions to induce structural distortions and thus to limit energy migration. Room-temperature self-activated luminescence of Ca2 Nb2 O7 was accordingly achieved in submicroplates synthesized using the sol-gel method. By further coupling the blue broadband emission from Ca2 Nb2 O7 submicroplates with the characteristic luminescence of Ln3+ (Pr3+ , Sm3+ , and Dy3+ ) dopants, multicolor emissions were successively tuned through adjusting the concentration of Ln3+ . Our results are expected to expand the scope of designing room-temperature self-activated phosphors and tuning multicolor emission.

14.
Nanotechnology ; 27(14): 145704, 2016 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-26906625

RESUMEN

Transition-metal dichalcogenide (TMD) semiconductors have been widely studied due to their distinctive electronic and optical properties. The property of TMD flakes is a function of their thickness, or layer number (N). How to determine the N of ultrathin TMD materials is of primary importance for fundamental study and practical applications. Raman mode intensity from substrates has been used to identify the N of intrinsic and defective multilayer graphenes up to N = 100. However, such analysis is not applicable to ultrathin TMD flakes due to the lack of a unified complex refractive index (ñ) from monolayer to bulk TMDs. Here, we discuss the N identification of TMD flakes on the SiO2/Si substrate by the intensity ratio between the Si peak from 100 nm (or 89 nm) SiO2/Si substrates underneath TMD flakes and that from bare SiO2/Si substrates. We assume the real part of ñ of TMD flakes as that of monolayer TMD and treat the imaginary part of ñ as a fitting parameter to fit the experimental intensity ratio. An empirical ñ, namely, ñ(eff), of ultrathin MoS2, WS2 and WSe2 flakes from monolayer to multilayer is obtained for typical laser excitations (2.54 eV, 2.34 eV or 2.09 eV). The fitted ñ(eff) of MoS2 has been used to identify the N of MoS2 flakes deposited on 302 nm SiO2/Si substrate, which agrees well with that determined from their shear and layer-breathing modes. This technique of measuring Raman intensity from the substrate can be extended to identify the N of ultrathin 2D flakes with N-dependent ñ. For application purposes, the intensity ratio excited by specific laser excitations has been provided for MoS2, WS2 and WSe2 flakes and multilayer graphene flakes deposited on Si substrates covered by a 80-110 nm or 280-310 nm SiO2 layer.

15.
Nanoscale ; 8(5): 2944-50, 2016 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-26781815

RESUMEN

A facile fabrication strategy via electrospinning and followed by in situ polymerization to fabricate a patterned, highly stretchable, and conductive polyaniline/poly(vinylidene fluoride) (PANI/PVDF) nanofibrous membrane is reported. Owing to the patterned structure, the nanofibrous PANI/PVDF strain sensor can detect a strain up to 110%, for comparison, which is 2.6 times higher than the common nonwoven PANI/PVDF mat and much larger than the previously reported values (usually less than 15%). Meanwhile, the conductivity of the patterned strain sensor shows a linear response to the applied strain in a wide range from 0% to about 85%. Additionally, the patterned PANI/PVDF strain sensor can completely recover to its original electrical and mechanical values within a strain range of more than 22%, and exhibits good durability over 10,000 folding-unfolding tests. Furthermore, the strain sensor also can be used to detect finger motion. The results demonstrate promising application of the patterned nanofibrous membrane in flexible electronic fields.

16.
Gene ; 577(1): 14-23, 2016 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-26602029

RESUMEN

Canadian double-muscled Large White pigs are characterized by notable muscle mass, showing high daily gain and lean rate and good meat quality. In order to identify the major genes or proteins involved in muscle hyperplasia and hypertrophy, three pairs of full-sib pigs with extreme muscle mass difference from Canadian Large White were selected as experimental animals at 3 months age. The phenotypic differences of longissimus dorsi muscles (LD) were investigated with microarray and proteomics (2-DE, MALDI-TOF-MS), and results were verified by real-time PCR and western bolting respectively. The gene expressing profiling identified 57 and 260 and 147 differently expressed genes (DEGs) from the three pairs respectively with Bayesian statistics and significant analysis of microarrays (SAM) (p<0.05, q<0.05, fold>2). From the network of these DEGs, some major genes were displayed, such as EGF, PPARG, FN1, SERPINE1, MYC, JUN, involved in Wnt, MAPK and TGF-ß signal pathway respectively, which mainly participated in cell differentiation and proliferation. In parallel, proteomics analyses revealed 50 differently expressed protein (DEP) spots with mass spectrum, and 33 spots of them were found annotated, which took part in energy metabolism and the structure and contraction of muscle fiber. In brief, our integrated study provides a good foundation for the further study on the genetic mechanism of the double muscle traits in pigs.


Asunto(s)
Perfilación de la Expresión Génica/veterinaria , Carne/normas , Músculo Esquelético/metabolismo , Proteómica , Porcinos , Animales , Teorema de Bayes , Canadá , Electroforesis en Gel Bidimensional/veterinaria , Ontología de Genes , Redes Reguladoras de Genes , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos/veterinaria , Fenotipo , Transducción de Señal , Especificidad de la Especie , Espectrometría de Masa por Ionización de Electrospray/veterinaria , Porcinos/genética , Porcinos/crecimiento & desarrollo , Porcinos/metabolismo
17.
Nanoscale ; 7(29): 12351-5, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26154994

RESUMEN

Electrospinning (e-spinning) still has certain limitations in flexible practicability because its conventional setup is usually quite bulky and excessively dependent on a plug (electric supply). In this article, we report on a battery-operated e-spinning apparatus (BOEA) based on miniaturization and integration. The new device gets liberated from the conventional heavy power supply, achieves the tight integration of functional parts and can be operated by a single hand due to its small volume (10.5 × 5 × 3 cm(3)) and light weight (about 120 g). Different polymers such as polyvinylpyrrolidone (PVP), polycaprolactone (PCL), polystyrene (PS), poly(lactic acid) (PLA) and poly(vinylidene fluoride) (PVDF) were electrospun into fibers successfully, which confirms the stable performance and good real-time control capability of the apparatus. These results demonstrate that the BOEA could be potentially applied in many fields, especially in biomedical fields such as skin damage, wound healing, rapid hemostasis, etc.

18.
ACS Nano ; 9(7): 7440-9, 2015 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-26062640

RESUMEN

Raman spectroscopy is the prime nondestructive characterization tool for graphene and related layered materials. The shear (C) and layer breathing modes (LBMs) are due to relative motions of the planes, either perpendicular or parallel to their normal. This allows one to directly probe the interlayer interactions in multilayer samples. Graphene and other two-dimensional (2d) crystals can be combined to form various hybrids and heterostructures, creating materials on demand with properties determined by the interlayer interaction. This is the case even for a single material, where multilayer stacks with different relative orientations have different optical and electronic properties. In twisted multilayer graphene there is a significant enhancement of the C modes due to resonance with new optically allowed electronic transitions, determined by the relative orientation of the layers. Here we show that this applies also to the LBMs, which can be now directly measured at room temperature. We find that twisting has a small effect on LBMs, quite different from the case of the C modes. This implies that the periodicity mismatch between two twisted layers mostly affects shear interactions. Our work shows that ultralow-frequency Raman spectroscopy is an ideal tool to uncover the interface coupling of 2d hybrids and heterostructures.

19.
Nanoscale ; 7(17): 8135-41, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25875074

RESUMEN

An SiO2/Si substrate has been widely used to support two-dimensional (2d) flakes grown by chemical vapor deposition or prepared by micromechanical cleavage. The Raman intensity of the vibration modes of 2d flakes is used to identify the layer number of 2d flakes on the SiO2/Si substrate, however, such an intensity is usually dependent on the flake quality, crystal orientation and laser polarization. Here, we used graphene flakes, a prototype system, to demonstrate how to use the intensity ratio between the Si peak from SiO2/Si substrates underneath graphene flakes and that from bare SiO2/Si substrates for the layer-number identification of graphene flakes up to 100 layers. This technique is robust, fast and nondestructive against sample orientation, laser excitation and the presence of defects in the graphene layers. The effect of relevant experimental parameters on the layer-number identification was discussed in detail, such as the thickness of the SiO2 layer, laser excitation wavelength and numerical aperture of the used objective. This paves the way to use Raman signals from dielectric substrates for layer-number identification of ultrathin flakes of various 2d materials.

20.
Nanoscale Res Lett ; 10: 21, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25852319

RESUMEN

CdS is one of the important II-VI group semiconductors. In this paper, the electrical transport behavior of an individual CdS microrope composed of twisted nanowires is studied. It is found that the current-voltage (I-V) characteristics show two distinct power law regions from 360 down to 60 K. Space-charge-limited current (SCLC) theory is used to explain these temperature- and electric-field-dependent I-V curves. The I-V data can be well fitted by this theory above 100 K, and the corresponding carrier mobility, trap energy, and trap concentration are also obtained. However, the I-V data exhibit some features of the Coulomb blockade effect below 80 K.

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