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1.
Proc Natl Acad Sci U S A ; 120(3): e2212075120, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36634137

RESUMO

Liquid methanol has the potential to be the hydrogen energy carrier and storage medium for the future green economy. However, there are still many challenges before zero-emission, affordable molecular H2 can be extracted from methanol with high performance. Here, we present noble-metal-free Cu-WC/W plasmonic nanohybrids which exhibit unsurpassed solar H2 extraction efficiency from pure methanol of 2,176.7 µmol g-1 h-1 at room temperature and normal pressure. Macro-to-micro experiments and simulations unveil that local reaction microenvironments are generated by the coperturbation of WC/W's lattice strain and infrared-plasmonic electric field. It enables spontaneous but selective zero-emission reaction pathways. Such microenvironments are found to be highly cooperative with solar-broadband-plasmon-excited charge carriers flowing from Cu to WC surfaces for efficient stable CH3OH plasmonic reforming with C3-dominated liquid products and 100% selective gaseous H2. Such high efficiency, without any COx emission, can be sustained for over a thousand-hour operation without obvious degradation.

2.
Chem Rev ; 123(2): 701-735, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36577085

RESUMO

Self-healing materials open new prospects for more sustainable technologies with improved material performance and devices' longevity. We present an overview of the recent developments in the field of intrinsically self-healing polymers, the broad class of materials based mostly on polymers with dynamic covalent and noncovalent bonds. We describe the current models of self-healing mechanisms and discuss several examples of systems with different types of dynamic bonds, from various hydrogen bonds to dynamic covalent bonds. The recent advances indicate that the most intriguing results are obtained on the systems that have combined different types of dynamic bonds. These materials demonstrate high toughness along with a relatively fast self-healing rate. There is a clear trade-off relationship between the rate of self-healing and mechanical modulus of the materials, and we propose design principles of polymers toward surpassing this trade-off. We also discuss various applications of intrinsically self-healing polymers in different technologies and summarize the current challenges in the field. This review intends to provide guidance for the design of intrinsic self-healing polymers with required properties.

3.
J Med Virol ; 95(1): e28259, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36305096

RESUMO

The interferon-inducible protein with tetrapeptide repeats 3 (IFIT3) is one of the most important members in both the IFIT family and interferon-stimulated genes family. IFIT3 has typical features of the IFIT family in terms of gene and protein structures, and is able to be activated through the classical PRRs-IFN-JAK/STAT pathway. A variety of viruses can induce the expression of IFIT3, which in turn inhibits the replication of viruses, with the underlying mechanism showing its crucial role in antiviral innate immunity. Emerging studies have also identified that IFIT3 is involved in cellular biology changes, including cell proliferation, apoptosis, differentiation, and cancer development. In this review, we summarize the characteristics of IFIT3 with respect to molecular structure and regulatory pathways, highlighting the role of IFIT3 in antiviral innate immunity, as well as its diverse biological roles. We also discuss the potential of IFIT3 as a biomarker in disease diagnosis and therapy.


Assuntos
Antivirais , Janus Quinases , Humanos , Antivirais/uso terapêutico , Janus Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo , Imunidade Inata , Proteínas , Interferons/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
4.
Angew Chem Int Ed Engl ; 62(47): e202310989, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37783669

RESUMO

Despite intensive research on sustainable elastomers, achieving elastic vitrimers with significantly improved mechanical properties and recyclability remains a scientific challenge. Herein, inspired by the classical elasticity theory, we present a design principle for ultra-tough and highly recyclable elastic vitrimers with a defined network constructed by chemically crosslinking the pre-synthesized disulfide-containing polydimethylsiloxane (PDMS) chains with tetra-arm polyethylene glycol (PEG). The defined network is achieved by the reduced dangling short chains and the relatively uniform molecular weight of network strands. Such elastic vitrimers with the defined network, i.e., PDMS-disulfide-D, exhibit significantly improved mechanical performance than random analogous, previously reported PDMS vitrimers, and even commercial silicone-based thermosets. Moreover, unlike the vitrimers with random network that show obvious loss in mechanical properties after recycling, those with the defined network enable excellent thermal recyclability. The PDMS-disulfide-D also deliver comparable electrochemical signals if utilized as substrates for electromyography sensors after the recycling. The multiple relaxation processes are revealed via a unique physical approach. Multiple techniques are also applied to unravel the microscopic mechanism of the excellent mechanical performance and recyclability of such defined network.

5.
Small ; 18(19): e2200533, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35388964

RESUMO

The demand for stretchable electronics with a broader working range is increasing for wide application in wearable sensors and e-skin. However, stretchable conductors based on soft elastomers always exhibit low working range due to the inhomogeneous breakage of the conductive network when stretched. Here, a highly stretchable and self-healable conductor is reported by adopting polyrotaxane and disulfide bonds into the binding layer. The binding layer (PR-SS) builds the bridge between polymer substrates (PU-SS) and silver nanowires (AgNWs). The incorporation of sliding molecules endows the stretchable conductor with a long sensing range (190%) due to the energy dissipation derived from the sliding nature of polyrotaxanes, which is two times higher than the working range (93%) of conductors based on AP-SS without polyrotaxanes. Furthermore, the mechanism of sliding effect for the polyrotaxanes in the elastomers is investigated by SEM for morphological change of AgNWs, in situ small-angle x-ray scattering, as well as stress relaxation experiments. Finally, human-body-related sensing tests and a self-correction system in fitness are designed and demonstrated.


Assuntos
Ciclodextrinas , Rotaxanos , Elastômeros/química , Condutividade Elétrica , Humanos , Polímeros/química
6.
J Med Virol ; 94(10): 4677-4688, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35652186

RESUMO

Cancer is still ranked as a leading cause of death according to estimates from the World Health Organization (WHO) and the strong link between tumor viruses and human cancers have been proved for almost six decades. Cell-free DNA (cfDNA) has drawn enormous attention for its dynamic, instant, and noninvasive advantages as one popular type of cancer biomarker. cfDNAs are mainly released from apoptotic cells and exosomes released from cancer cells, including those infected with viruses. Although cfDNAs are present at low concentrations in peripheral blood, they can reflect tumor load with high sensitivity. Considering the relevance of the tumor viruses to the associated cancers, cfDNAs derived from viruses may serve as good biomarkers for the early screening, diagnosis, and treatment monitoring. In this review, we summarize the methods and newly developed analytic techniques for the detection of cfDNAs from different body fluids, and discuss the implications of cfDNAs derived from different tumor viruses in the detection and treatment monitoring of virus-associated cancers. A better understanding of cfDNAs derived from tumor viruses may help formulate novel antitumoral strategies to decrease the burden of cancers that attributed to viruses.


Assuntos
Ácidos Nucleicos Livres , Neoplasias , Biomarcadores Tumorais , Ácidos Nucleicos Livres/genética , DNA de Neoplasias/genética , Humanos , Neoplasias/diagnóstico , Neoplasias/patologia , Vírus Oncogênicos/genética
7.
Langmuir ; 38(32): 9751-9759, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35921602

RESUMO

Interfacial properties of polymeric materials are significantly influenced by their architectural structures and spatial features, while such a study of topologically interesting macromolecules is rarely reported. In this work, we reported, for the first time, the interfacial behavior of catenated poly(l-lactide) (C-PLA) at the air-water interface and compared it with its linear analogue (L-PLA). The isotherms of surface pressure-area per repeating unit showed significant interfacial behavioral differences between the two polymers with different topologies. Isobaric creep experiments and compression-expansion cycles also showed that C-PLA demonstrated higher stability at the air-water interface. Interestingly, when the films at different surface pressures were transferred via the Langmuir-Blodgett method, successive atomic force microscopy imaging displayed distinct nanomorphologies, in which the surface of C-PLA exhibited nanofibrous structures, while that of the L-PLA revealed a smoother topology with less fiber-like structures.


Assuntos
Ar , Água , Microscopia de Força Atômica , Poliésteres/química , Polímeros/química , Propriedades de Superfície , Água/química
8.
Nanotechnology ; 33(40)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35772294

RESUMO

A terahertz constant frequency reconfigurable metasurface based on tunable electromagnetically induced transparency (EIT)-like property was designed, whose transparency window frequency did not vary with Fermi energy. This structure was composed of two single-layer graphene resonators, namely, left double big rings and right double small rings. An evident transparency window (EIT-like phenomenon) was caused by the near-field coupling between bright modes of the two resonators in the transmission spectrum, in which amplitude over 80% was acquired at 1.98 THz. By individually reconfiguring the Fermi energy of each resonator, the EIT-like effects, transparency window amplitude, modulation speed and group delay could be actively controlled while the frequency of EIT-like window remained constant. Significantly, the transparency window was fully modulated without changing the frequency, and the maximum modulation depth reached 78%. Furthermore, the modulation speed also increased because the total graphene areaAwas effectively reduced in the proposed structure. Compared with other metasurface structures, the modulation properties of the proposed structure showed higher performance while the EIT-like window frequency remained static. This research provides an alternative method for developing constant frequency reconfigurable modulation terahertz devices (such as optical switches and modulators), as well as a potential approach for miniaturization of terahertz devices.

9.
Crit Rev Microbiol ; 47(1): 112-125, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33245676

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a novel bunyavirus. Since 2007, SFTS disease has been reported in China with high fatality rate up to 30%, which drew high attention from Centre for Disease Control and Prevention and government. SFTSV is endemic in the centra l and eastern China, Korea and Japan. There also have been similar cases reported in Vietnam. The number of SFTSV infection cases has a steady growth in these years. As SFTSV could transmitted from person to person, it will expose the public to infectious risk. In 2018 annual review of the Blueprint list of priority diseases, World Health Organisation has listed SFTSV infection as prioritised diseases for research and development in emergency contexts. However, the pathogenesis of SFTSV remains largely unclear. Currently, there are no specific therapeutics or vaccines to combat infections of SFTSV. This review discusses recent findings of epidemiology, transmission pathway, pathogenesis and treatments of SFTS disease.


Assuntos
Phlebovirus/fisiologia , Phlebovirus/patogenicidade , Febre Grave com Síndrome de Trombocitopenia/virologia , Animais , Ásia/epidemiologia , Humanos , Phlebovirus/genética , Febre Grave com Síndrome de Trombocitopenia/epidemiologia , Febre Grave com Síndrome de Trombocitopenia/mortalidade , Febre Grave com Síndrome de Trombocitopenia/transmissão , Virulência
10.
Plant Cell ; 30(10): 2267-2285, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30254029

RESUMO

Alternative splicing (AS) of pre-mRNAs promotes transcriptome and proteome diversity and plays important roles in a wide range of biological processes. However, the role of AS in maintaining mineral nutrient homeostasis in plants is largely unknown. To clarify this role, we obtained whole transcriptome RNA sequencing data from rice (Oryza sativa) roots grown in the presence or absence of several mineral nutrients (Fe, Zn, Cu, Mn, and P). Our systematic analysis revealed 13,291 alternatively spliced genes, representing ∼53.3% of the multiexon genes in the rice genome. As the overlap between differentially expressed genes and differentially alternatively spliced genes is small, a molecular understanding of the plant's response to mineral deficiency is limited by analyzing differentially expressed genes alone. We found that the targets of AS are highly nutrient-specific. To verify the role of AS in mineral nutrition, we characterized mutants in genes encoding Ser/Arg (SR) proteins that function in AS. We identified several SR proteins as critical regulators of Zn, Mn, and P nutrition and showed that three SR protein-encoding genes regulate P uptake and remobilization between leaves and shoots of rice, demonstrating that AS has a key role in regulating mineral nutrient homeostasis in rice.


Assuntos
Processamento Alternativo , Minerais/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Homeostase/fisiologia , Mutação , Fosfatos/metabolismo , Fosfatos/farmacocinética , Fósforo/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo
11.
Langmuir ; 37(25): 7681-7688, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34139839

RESUMO

The influence of mercury on the morphology and formation mechanism of gold amalgams in the presence of different reducing agents (ascorbic acid and sodium borohydride) was systematically studied. In the presence of cetyltrimethylammonium bromide (CTAB), chemical reducing agents not only reduced mercury ions in the solution but also replaced the CTAB molecules on the surface of the gold nanorod. The stability of the reducing agents in the colloidal system and the combining capacity of the reducing agent to the gold nanoparticles can affect the alloying process of mercury and gold, thereby forming a rod-shaped or spherical gold amalgam. Once CTAB was removed, a similar transformation process occurs between the gold nanorods and mercury. In addition, without the presence of a stabilizer, mercury that cannot be dispersed undergoes Ostwald ripening growth, which causes the gold amalgam nanoalloys to form a tip-to-tip structure as a result of mercury enrichment because of the weak shielding effects occurring at the tips of the gold nanorods. After the CTAB molecules were substituted with ascorbic acid and alkylthiol molecules, the question of whether the shielding effect weakened or disappeared was also investigated. By investigation, this research found that, in comparison to the blocking effect of CTAB molecules, the binding ability of the reducing agent to gold plays a dominant role in the nanoamalgam formation process.


Assuntos
Nanopartículas Metálicas , Nanotubos , Compostos de Cetrimônio , Ouro , Substâncias Redutoras
12.
Inorg Chem ; 60(5): 3471-3478, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33591166

RESUMO

Hollow multimetallic noble nanoalloys with high surface area/volume ratio, abundant active sites, and relatively effective catalytic activity have attracted considerable research interest. Traditional noble nanoalloys fabricated by hydro-/solvothermal methods usually involve harsh synthetic conditions such as high temperatures and intricate processing. We proposed a simple and mild strategy to synthesize platinum- and palladium-decorated hollow gold-based nanoalloys by the galvanic replacement reaction (GRR) at room temperature using hollow gold nanoparticles as templates and mercury as an intermediate. The hollow gold nanoparticles were essential for increasing the number of surface-active sites of the obtained multimetallic nanoalloys, and the introduction of mercury can eliminate the influence of the electrochemical potential of Pt/Pd with Au in the GRRs, increase alloying degrees, and maintain the nanoalloys that exhibit the hollow nanostructures. The structural characterizations of the hollow nanoalloys were studied by means of high-angle annular dark-field scanning transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. On the basis of the electrochemical catalytic measurements, the platinum-exposed nanoalloys were found to have excellent electrocatalytic activities. Especially in the presence of palladium, owing to the synergistic effect, the quaternary AuHgPdPt hollow nanoalloy displayed a low overpotential of 38 mV at 10 mA cm-2 with a small Tafel slope of 56.23 mV dec-1 for the alkaline hydrogen evolution reaction. In addition, this approach not only expands the application range of the galvanic replacement reaction but also provides new ideas for the preparation of multialloys and even high-entropy alloys at room temperature.

13.
Phytother Res ; 35(4): 2157-2170, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33274566

RESUMO

Chronic myelomonocytic leukemia (CML) is a myeloid tumor characterized by MDS (myelodysplastic syndrome) and MPN (myeloproliferative neoplasms). Allogeneic hematopoietic stem cell transplantation, chemotherapy, interferon, and targeted therapy are the main treatment methods for CML. Tyrosine kinase inhibitors (TKIs) are also a treatment option, and patients are currently recommended to take these drugs throughout their lives to prevent CML recurrence. Therefore, there is a need to investigate and identify other potential chemotherapy drugs. Currently, research on CML treatment with a single drug has shown little progress. Fingolimod (FTY720), an FDA-approved drug used to treat relapsing multiple sclerosis, has also shown great potential in the treatment of lymphocytic leukemia. In our study, we find that FTY720 and curcumol have a significant inhibitory effect on K562 cells, K562/ADR cells, and CD34+ cells from CML patients. RNAseq data analysis shows that regulation of apoptosis and differentiation pathways are key pathways in this process. Besides, BCR/ABL-Jak2/STAT3 signaling, PI3K/Akt-Jnk signaling, and activation of BH3-only genes are involved in CML inhibition. In a K562 xenograft mouse model, therapy with curcumol and FTY720 led to significant inhibition of tumor growth and induction of apoptosis. To summarize, curcumol and FTY720 synergistically inhibit proliferation involved in differentiation and induce apoptosis in CML cells. Therefore, synergistic treatment with two drugs could be the next choice of treatment for CML.


Assuntos
Cloridrato de Fingolimode/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Sesquiterpenos/uso terapêutico , Animais , Apoptose , Diferenciação Celular , Proliferação de Células , Modelos Animais de Doenças , Cloridrato de Fingolimode/farmacologia , Humanos , Camundongos , Sesquiterpenos/farmacologia , Transdução de Sinais
14.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(5): 552-557, 2021 May 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34148893

RESUMO

Lymphoma is one of the most common malignant tumor of the hematologic system. The genome instability is not only an important molecular basis for the development of lymphoma, but also has important value in the diagnosis and prognosis of lymphoma. There are 2 types of genome instability: Microsatellite instability (MSI/MIN) at gene level and chromosomal instability at chromosome level. Through the study on genes associated with lymphoma, the unstable genes associated with lymphoma could be found, meanwhile the mechanism of its occurrence and development of lymphoma could be explored, and the important basis of molecular biology could also be provided in the field of current hot lymphoma precision medical research.


Assuntos
Linfoma , Neoplasias , Instabilidade Genômica , Humanos , Linfoma/genética , Instabilidade de Microssatélites , Repetições de Microssatélites
15.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(3): 322-327, 2021 Mar 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33927081

RESUMO

Chronic myeloid leukemia with a significant increase of monocytes is rare and difficult to identify from chronic myelo-monocytic leukemia in clinic. A 31-year-old male patient with systemic pain was initially diagnosed as chronic myelo-monocytic leukemia, who was finally diagnosed as chronic myeloid leukemia by fusion gene and chromosome examination. In addition to the typical Ph chromosome, a rare chromosome translocation t(2; 7)(p13; p22) was observed. The detection of monocyte subsets by multi-parameter flow cytometry is a diagnostic marker to distinguish the above 2 diseases. The relationship between fusion genes and mononucleosis is not clear. Tyrosine kinase inhibitors or allogeneic hematopoietic stem cell transplantation can be used in the treatment for this disease.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Monócitos , Adulto , Humanos , Cariótipo , Cariotipagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Translocação Genética
16.
Blood Cells Mol Dis ; 85: 102477, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32711219

RESUMO

Chronic myeloid leukemia (CML) is a kind of myeloproliferative disorder caused by a constitutively active BCR-ABL tyrosine kinase. Tyrosine kinase inhibitors (TKIs), imatinib and its derivatives, have achieved great progress in the treatment of CML. However, many CML patients do not respond to TKIs alone. p19INK4d, a cyclin-dependent kinase inhibitor, plays important roles in proliferation, DNA damage repair, apoptosis and cell differentiation, but its role in CML is unknown. Herein, we found that the expression of p19INK4d in CML patients was significantly lower than that in healthy controls. p19INK4d overexpression inhibits cell proliferation through cell cycle arrest, and cooperates with imatinib to inhibit CML more effectively in vitro and in vivo. Mechanistically, p19INK4d decreased the expression of BCR-ABL and its downstream molecules p-Mek1/2, moreover, the expression of Gli-1, c-myc, MUC1, Shh and TC48 also reduced significantly. Collectively, p19INK4d inhibits proliferation and enhances imatinib efficacy in the treatment of CML. These findings maybe have implications for developing potential targets to increase imatinib sensitivity for CML.


Assuntos
Antineoplásicos/uso terapêutico , Inibidor de Quinase Dependente de Ciclina p19/genética , Proteínas de Fusão bcr-abl/genética , Regulação Leucêmica da Expressão Gênica , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p19/metabolismo , Proteínas de Fusão bcr-abl/metabolismo , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib/farmacologia , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Camundongos Nus , Transdução de Sinais/efeitos dos fármacos
17.
Virol J ; 17(1): 51, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32272952

RESUMO

The Epstein-Barr virus (EBV) is a ubiquitous γ-herpesvirus related to various types of cancers, including epithelial nasopharyngeal carcinoma, gastric carcinoma, and lymphoma. Long noncoding RNAs (lncRNAs) are expressed extensively in mammalian cells and play crucial roles in regulating various cellular processes and multiple cancers. Cellular lncRNAs can be differentially expressed induced by EBV infection. The dysregulated lncRNAs probably modulate the host immune response and other biological functions. At present, lncRNAs have been found to be significantly increased or decreased in EBV-infected cells, exosomes and EBV-associated cancers, suggesting their potential function and clinical application as biomarkers. In addition, EBV-encoded lncRNAs, BART and BHLF1 lncRNAs, may play roles in the viral oncogenesis. Analysis of the specific lncRNAs involved in interactions with the EBV machinery will provide information on their potential mechanism of action during multiple steps of EBV tumorigenesis. Here, we review the current knowledge regarding EBV-related lncRNAs and their possible roles in the pathogenesis of EBV-associated cancers.


Assuntos
Carcinogênese/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , RNA Longo não Codificante , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/genética , Humanos , RNA Viral , Análise de Sequência de RNA
18.
Soft Matter ; 16(2): 390-401, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31840152

RESUMO

Recent findings that the association bond lifetimes τα* in associating polymers diverge from their supramolecular network relaxation times τc challenge past theories. The bond lifetime renormalization proposed by Rubinstein and coworkers [Stukalin et al., Macromolecules, 2013, 46, 7525] provides a promising explanation. To examine systematically its applicability, we employ shear rheology and dielectric spectroscopy to study telechelic associating polymers with different main chain (polypropylene glycol and polydimethylsiloxane), molecular weight (below entanglement molecular weight) and end groups (amide, and carboxylic acid) which form dimeric associations by hydrogen bonding. The separation between τc (probed by rheology) and τα* (probed by dielectric spectroscopy) strongly increases with chain length as qualitatively predicted by the model. However, to describe the increase quantitatively, a transition from Rouse to reptation dynamics must be assumed. This suggests that dynamics of super-chains must be considered to properly describe the transient network.

19.
Nanotechnology ; 31(36): 365501, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32443000

RESUMO

To improve the refractive index sensitivity of a localized surface plasmon resonance (LSPR) sensor, we employ a new interparticle hybridization plasmon coupled resonance in a semiconductor-metal (Cu2-xS@Au) core-shell nanoparticle dimer (SMCSND), where the refractive index sensitivity can be improved by the generation of a tunable dual-band absorption spectrum at visible and near-infrared wavelengths. Owing to two LSPRs in different wavelength regions supported by the metal shell and semiconductor core, for the first time, we theoretically demonstrate that the new interparticle hybridization plasmon coupled mechanism in semiconductor-metal core-shell nanoparticle dimer depends not only on interparticle separation gap, but also on the nanoparticle shell thickness t. Electromagnetic model analysis reveals that there are two plasmon modes (Mode A and Mode C) associated with the interparticle hybridization plasmon coupled resonance, where the Mode C shows high sensitivity and figure of merit (FoM) to changes in the background dielectric medium. The tunability of the induced interparticle hybridization plasmon coupled resonance with different the separation distance and shell thickness can change the sensitivity and FoM of LSPR sensor in the visible to near-infrared region, which has broad application prospects.

20.
Chemistry ; 25(47): 10976-10994, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31041811

RESUMO

Silicon (Si) is a promising candidate for high-capacity anode materials owing to its high theoretical capacity (3579 mAh g-1 ), low working voltage, and wide natural abundance, although its huge volume variation during charge/discharge processes always results in a short cycling life. Polymer binders play a vital role in improving the cycling performance of Si-based anodes, although traditional polyvinylidene difluoride cannot fulfil the requirements owing to its weak van der Waals forces with the Si surface. Recently, polymer binders constructed by dynamic bonds have been developed, which are reported to allow high-energy-density electrodes with improved electrochemical performance. With dynamic bonds including hydrogen bonding, ionic bonding, and host-guest interactions, these polymer binders possess self-healing capabilities and enhanced mechanical performance, achieving a tremendous advance in addressing the capacity fading of Si-based anodes. In this review, we will summarize the research progress of polymer binders constructed with dynamic bonds, and the challenges for their real applications in advanced Li-ion batteries will also be discussed.

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