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1.
Nature ; 597(7874): 57-63, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34471277

RESUMO

Fibre lithium-ion batteries are attractive as flexible power solutions because they can be woven into textiles, offering a convenient way to power future wearable electronics1-4. However, they are difficult to produce in lengths of more than a few centimetres, and longer fibres were thought to have higher internal resistances3,5 that compromised electrochemical performance6,7. Here we show that the internal resistance of such fibres has a hyperbolic cotangent function relationship with fibre length, where it first decreases before levelling off as length increases. Systematic studies confirm that this unexpected result is true for different fibre batteries. We are able to produce metres of high-performing fibre lithium-ion batteries through an optimized scalable industrial process. Our mass-produced fibre batteries have an energy density of 85.69 watt hour per kilogram (typical values8 are less than 1 watt hour per kilogram), based on the total weight of a lithium cobalt oxide/graphite full battery, including packaging. Its capacity retention reaches 90.5% after 500 charge-discharge cycles and 93% at 1C rate (compared with 0.1C rate capacity), which is comparable to commercial batteries such as pouch cells. Over 80 per cent capacity can be maintained after bending the fibre for 100,000 cycles. We show that fibre lithium-ion batteries woven into safe and washable textiles by industrial rapier loom can wirelessly charge a cell phone or power a health management jacket integrated with fibre sensors and a textile display.


Assuntos
Cobalto/química , Fontes de Energia Elétrica , Eletrônica , Lítio/química , Óxidos/química , Têxteis , Dispositivos Eletrônicos Vestíveis , Grafite/química , Humanos , Íons , Masculino , Tecnologia sem Fio
2.
Acta Pharmacol Sin ; 45(7): 1438-1450, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38565961

RESUMO

Angiogenesis plays a critical role in many pathological processes, including irreversible blindness in eye diseases such as retinopathy of prematurity. Endothelial mitochondria are dynamic organelles that undergo constant fusion and fission and are critical signalling hubs that modulate angiogenesis by coordinating reactive oxygen species (ROS) production and calcium signalling and metabolism. In this study, we investigated the role of mitochondrial dynamics in pathological retinal angiogenesis. We showed that treatment with vascular endothelial growth factor (VEGF; 20 ng/ml) induced mitochondrial fission in HUVECs by promoting the phosphorylation of dynamin-related protein 1 (DRP1). DRP1 knockdown or pretreatment with the DRP1 inhibitor Mdivi-1 (5 µM) blocked VEGF-induced cell migration, proliferation, and tube formation in HUVECs. We demonstrated that VEGF treatment increased mitochondrial ROS production in HUVECs, which was necessary for HIF-1α-dependent glycolysis, as well as proliferation, migration, and tube formation, and the inhibition of mitochondrial fission prevented VEGF-induced mitochondrial ROS production. In an oxygen-induced retinopathy (OIR) mouse model, we found that active DRP1 was highly expressed in endothelial cells in neovascular tufts. The administration of Mdivi-1 (10 mg·kg-1·d-1, i.p.) for three days from postnatal day (P) 13 until P15 significantly alleviated pathological angiogenesis in the retina. Our results suggest that targeting mitochondrial fission may be a therapeutic strategy for proliferative retinopathies and other diseases that are dependent on pathological angiogenesis.


Assuntos
Movimento Celular , Dinaminas , Células Endoteliais da Veia Umbilical Humana , Subunidade alfa do Fator 1 Induzível por Hipóxia , Camundongos Endogâmicos C57BL , Dinâmica Mitocondrial , Quinazolinonas , Espécies Reativas de Oxigênio , Neovascularização Retiniana , Fator A de Crescimento do Endotélio Vascular , Dinâmica Mitocondrial/efeitos dos fármacos , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Dinaminas/metabolismo , Dinaminas/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo , Quinazolinonas/farmacologia , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Neovascularização Retiniana/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Camundongos , Proliferação de Células/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Angiogênese
3.
Mikrochim Acta ; 191(6): 300, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709399

RESUMO

Glycated hemoglobin (HbA1c), originating from the non-enzymatic glycosylation of ßVal1 residues in hemoglobin (Hb), is an essential biomarker indicating average blood glucose levels over a period of 2 to 3 months without external environmental disturbances, thereby serving as the gold standard in the management of diabetes instead of blood glucose testing. The emergence of HbA1c biosensors presents affordable, readily available options for glycemic monitoring, offering significant benefits to small-scale laboratories and clinics. Utilizing nanomaterials coupled with high-specificity probes as integral components for recognition, labeling, and signal transduction, these sensors demonstrate exceptional sensitivity and selectivity in HbA1c detection. This review mainly focuses on the emerging probes and strategies integral to HbA1c sensor development. We discussed the advantages and limitations of various probes in sensor construction as well as recent advances in diverse sensing strategies for HbA1c measurement and their potential clinical applications, highlighting the critical gaps in current technologies and future needs in this evolving field.


Assuntos
Técnicas Biossensoriais , Hemoglobinas Glicadas , Hemoglobinas Glicadas/análise , Técnicas Biossensoriais/métodos , Humanos , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/sangue , Glicemia/análise
4.
Mikrochim Acta ; 191(2): 109, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38246895

RESUMO

Household storage of pharmaceuticals to extract raw materials synthesized from carbon points facilitates the utilization of solid waste resources. A novel ratiometric fluorescence sensing technique was developed to ascertain the presence of horseradish peroxidase (HRP) in fruits and vegetables. The method employed a fluorescent probe, synthesized from expired amoxicillin (referred to as carbon dots, or A-CDs), serving as a reference fluorophore. Additionally, 2,3-diaminophenazine (DAP) was utilized as a specific response signal. DAP resulted from a catalytic reaction system involving phenylenediamine and hydrogen peroxide under the catalysis of HRP. The fluorescence intensity corresponding to DAP at 562 nm exhibited a substantial increase, simultaneous with the fluorescence quenching of A-CDs at 450 nm. The ratiometric fluorescence nanosensors displayed a broad linear range and high sensitivity for the detection of HRP. Across the concentration range 0.01 to 6 U L-1, the fluorescence intensity ratio between DAP and A-CDs demonstrated a proportional increase with rising HRP concentration, achieving an impressive detection limit of 0.002 U L-1. The recovery of HRP in fruit and vegetable samples ranged from 96.1 to 103%, with an RSD value of less than 3.8%. The proposed method facilitated the screening of inhibitors of HRP enzyme activity, contributing to the preservation of freshness in fruits and vegetables.


Assuntos
Frutas , Verduras , Corantes Fluorescentes , Carbono , Peroxidase do Rábano Silvestre
5.
Molecules ; 29(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38398628

RESUMO

Inhibiting the activity of intestinal α-glucosidase is considered an effective approach for treating type II diabetes mellitus (T2DM). In this study, we employed an in vitro enzymatic synthesis approach to synthesize four derivatives of natural products (NPs) for the discovery of therapeutic drugs for T2DM. Network pharmacology analysis revealed that the betulinic acid derivative P3 exerted its effects in the treatment of T2DM through multiple targets. Neuroactive ligand-receptor interaction and the calcium signaling pathway were identified as key signaling pathways involved in the therapeutic action of compound P3 in T2DM. The results of molecular docking, molecular dynamics (MD) simulations, and binding free energy calculations indicate that compound P3 exhibits a more stable binding interaction and lower binding energy (-41.237 kcal/mol) with α-glucosidase compared to acarbose. In addition, compound P3 demonstrates excellent characteristics in various pharmacokinetic prediction models. Therefore, P3 holds promise as a lead compound for the development of drugs for T2DM and warrants further exploration. Finally, we performed site-directed mutagenesis to achieve targeted synthesis of betulinic acid derivative. This work demonstrates a practical strategy of discovering novel anti-hyperglycemic drugs from derivatives of NPs synthesized through in vitro enzymatic synthesis technology, providing potential insights into compound P3 as a lead compound for anti-hyperglycemic drug development.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Simulação de Acoplamento Molecular , Inibidores de Glicosídeo Hidrolases/química , alfa-Glucosidases/metabolismo , Ácido Betulínico
6.
Phys Chem Chem Phys ; 25(4): 3270-3278, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36625732

RESUMO

Short-wave ultraviolet (also called UVC) irradiation is a well-adopted method of viral inactivation due to its ability to damage genetic material. A fundamental problem with the UVC inactivation method is that its mechanism of action on viruses is still unknown at the molecular level. To address this problem, herein we investigate the response mechanism of genome materials to UVC light by means of quantum chemical calculations. The spectral properties of four nucleotides, namely, adenine, cytosine, guanine, and uracil, are mainly focused on. Meanwhile, the transition state and reaction rate constant of uracil molecules are also considered to demonstrate the difficulty level of adjacent nucleotide reaction without and with UVC irradiation. The results show that the peak wavelengths are 248.7 nm, 226.1 nm (252.7 nm), 248.3 nm, and 205.8 nm (249.2 nm) for adenine, cytosine, guanine, and uracil nucleotides, respectively. Besides, the reaction rate constants of uracil molecules are 6.419 × 10-49 s-1 M-1 and 5.436 × 1011 s-1 M-1 for the ground state and excited state, respectively. Their corresponding half-life values are 1.56 × 1048 s and 1.84 × 10-12 s. This directly suggests that the molecular reaction between nucleotides is a photochemical process and the reaction without UVC irradiation almost cannot occur.


Assuntos
Nucleotídeos , Uracila , Adenina , Citosina , Guanina , Raios Ultravioleta
7.
J Enzyme Inhib Med Chem ; 37(1): 2241-2255, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35978496

RESUMO

FAK mediated tumour cell migration, invasion, survival, proliferation and regulation of tumour stem cells through its kinase-dependent enzymatic functions and kinase-independent scaffolding functions. At present, the development of FAK PROTACs has become one of the hotspots in current pharmaceutical research to solve above problems. Herein, we designed and synthesised a series of FAK-targeting PROTACs consisted of PF-562271 derivative 1 and Pomalidomide. All compounds showed significant in vitro FAK kinase inhibitory activity, the IC50 value of the optimised PROTAC A13 was 26.4 nM. Further, A13 exhibited optimal protein degradation (85% degradation at 10 nM). Meantime, compared with PF-562271, PROTAC A13 exhibited better antiproliferative activity and anti-invasion ability in A549 cells. More, A13 had excellent plasma stability with T1/2 >194.8 min. There are various signs that PROTAC A13 could be useful as expand tool for studying functions of FAK in biological system and as potential therapeutic agents.


Assuntos
Antineoplásicos , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Fosforilação , Proteólise
8.
Opt Lett ; 46(9): 2147-2150, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33929440

RESUMO

In this Letter, we experimentally achieve high-speed ultraviolet-C (UVC) communication based on a 276.8 nm UVC micro-LED. A record ${-}{{3}}\;{\rm{dB}}$ optical bandwidth of 452.53 MHz and light output power of 0.854 mW at a current density of ${{400}}\;{\rm{A/c}}{{\rm{m}}^2}$ are obtained with a chip size of 100 µm. A UVC link over 0.5 m with a data rate of 2 Gbps is achieved using 16-ary quadrature amplitude modulation orthogonal frequency division multiplexing and pre-equalization, and an extended distance over 3 m with a data rate of 0.82 Gbps is also presented. The demonstrated high-speed performance shows that micro-LEDs have great potential in the field of UVC communication.

9.
Opt Express ; 28(9): 13921-13937, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32403858

RESUMO

Light-emitting diode (LED) arrays have attracted increased attention in the area of high power intelligent automotive headlamps because of their superiority in disposing of the power limit of an individual LED package and controllably luminous intensity and illumination pattern. The optical and chromatic performances of an LED array do not equal to the sum of individual LED packages' performances, as the thermal interactions between individual LED packages can't be ignored in the actual application. This paper presents a thermal-electrical-spectral (TES) model to dynamically predict the optical and chromatic performances of the LED array. The thermal-electrical (TE) model considering the thermal coupling effect in the LED array is firstly proposed to predict the case temperature of each individual LED package, and the Spectral power distributions (SPDs) of individual LED package is then decomposed by the extended Asym2sig model to extract the spectral characteristic parameters. Finally, the experimental measurements of the designed LED arrays operated under usage conditions are used to verify the TES model. Some validation case studies show that the prediction accuracy of the proposed TES model, which is expressed as a quadratic polynomial function of current and case temperature, can be achieved higher than 95%. Therefore, it can be concluded that this TES model offers a convenient method with high accuracy to dynamically predict the optical and chromatic performances of LED arrays at real usages.

10.
J Org Chem ; 85(6): 4515-4524, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32070098

RESUMO

A variety of substituted acridones were synthesized via a one-pot, metal-free cascade reaction. In this event, the DBU-mediated addition between quinols and ortho-methoxycarbonylaryl isocyanates formed a bicyclic oxazolidinone, followed by a sequence of intramolecular condensation, tautomerization, and decarboxylation, which led to the formation of acridones. The acridones showed mild activity against the human cytomegalovirus.


Assuntos
Hidroquinonas , Isocianatos , Descarboxilação , Humanos
11.
Nanotechnology ; 31(5): 055501, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31484166

RESUMO

Humidity sensors based on flexible sensitive nanomaterials are very attractive in noncontact healthcare monitoring. However, the existing humidity sensors have some shortcomings such as limited sensitivity, narrow relative humidity (RH) range, and a complex process. Herein, we show that a tin sulphide (SnS) nanoflakes-based sensor presents high humidity sensing behaviour both in rigid and flexible substrate. The sensing mechanism based on the Schottky nature of a SnS-metal contact endows the as-fabricated sensor with a high response of 2491000% towards a wide RH range from 3% RH to 99% RH. The response and recovery time of the sensor are 6 s and 4 s, respectively. Besides, the flexible SnS nanoflakes-based humidity sensor with a polyimide substrate can be well attached to the skin and exhibits stable humidity sensing performance in the natural flat state and under bending loading. Moreover, the first-principles analysis is performed to prove the high specificity of SnS to the moisture (H2O) in the air. Benefiting from its promising advantages, we explore some application of the SnS nanoflakes-based sensors in detection of breathing patterns and non-contact finger tips sensing behaviour. The sensor can monitor the respiration pattern of a human being accurately, and recognize the movement of the fingertip speedily. This novel humidity sensor shows great promising application in physiological and physical monitoring, portable diagnosis system, and noncontact interface localization.


Assuntos
Técnicas Biossensoriais/instrumentação , Umidade , Nanoestruturas/química , Sulfetos/química , Compostos de Estanho/química , Água/química , Humanos , Monitorização Ambulatorial/instrumentação , Nanoestruturas/ultraestrutura , Tempo de Reação , Dióxido de Silício/química , Propriedades de Superfície
12.
Phys Chem Chem Phys ; 22(21): 12321, 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32432242

RESUMO

Correction for 'Liquid-phase exfoliated SnS as a semiconductor coating filler to enhance corrosion protection performance' by Hongyu Tang et al., Phys. Chem. Chem. Phys., 2019, 21, 18179-18187, DOI: 10.1039/C9CP03381E.

13.
Lasers Med Sci ; 35(6): 1329-1339, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31900692

RESUMO

Anti-fungal blue light (ABL) therapies have been widely studied to treat various microbial infections in the literature. The blue light with wavelengths ranging from 400 to 470 nm has been reported to be effective to inhibit various kinds of bacteria and fungi. The existing studies usually report the viability rates of the pathogens under the irradiation of the blue light with different dosage parameters. However, to the best of our knowledge, there is still no work especially focusing on studying the effect of ABL therapies on treating candida vaginitis, where it is important to study the viability of both the Candida albicans (C. albicans) and the human vaginal epithelial cells. It is the purpose of this work to conduct ABL experiments on both of these two cells, analyze the effects, and determine the best ABL wavelength out of three candidates, i.e., 405-nm, 415-nm, and 450-nm wavelength. The viability rates of the C. albicans and the human vaginal epithelial cells irradiated by the three blue LED light sources were measured, whose irradiance (power density) were all set to 50 mW/cm2. The dynamic viability models of the C. albicans and the epithelial cells were built based on the experimental data. Moreover, in this work, we also built a functional relationship between the viability of these two types of cells, by which we further compared the effects of the blue light irradiation on both the C. albicans and vaginal epithelial cells. The experimental data showed that when an approximately 80% inhibiting rate of the C. albicans was achieved, the survival rates of the epithelial cells were 0.6700, 0.7748, and 0.6027, respectively for the treatment by the 405-nm, 415-nm, and 450-nm wavelength light. On the other hand, by simulating the functional relationship between the viability of the two types of cells, the survival rates of the epithelial cells became 0.5783, 0.6898, and 0.1918 respectively using the 405-nm, 415-nm and 450-nm wavelength light, when the C. albicans was completely inhibited. Therefore, both the experimental data and the model simulation results have demonstrated that the 415-nm light has a more effective anti-fungal result with less damage to the epithelial cells than the 405-nm and 450-nm light.


Assuntos
Candidíase Vulvovaginal/terapia , Luz , Fototerapia , Candida albicans/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Cor , Células Epiteliais/microbiologia , Células Epiteliais/efeitos da radiação , Feminino , Humanos , Viabilidade Microbiana/efeitos da radiação , Modelos Biológicos
14.
Entropy (Basel) ; 22(2)2020 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33286028

RESUMO

Understanding the defect characterization of electronic and mechanical components is a crucial step in diagnosing component lifetime. Technologies for determining reliability, such as thermal modeling, cohesion modeling, statistical distribution, and entropy generation analysis, have been developed widely. Defect analysis based on the irreversibility entropy generation methodology is favorable for electronic and mechanical components because the second law of thermodynamics plays a unique role in the analysis of various damage assessment problems encountered in the engineering field. In recent years, numerical and theoretical studies involving entropy generation methodologies have been carried out to predict and diagnose the lifetime of electronic and mechanical components. This work aimed to review previous defect analysis studies that used entropy generation methodologies for electronic and mechanical components. The methodologies are classified into two categories, namely, damage analysis for electronic devices and defect diagnosis for mechanical components. Entropy generation formulations are also divided into two detailed derivations and are summarized and discussed by combining their applications. This work is expected to clarify the relationship among entropy generation methodologies, and benefit the research and development of reliable engineering components.

15.
J Am Chem Soc ; 141(38): 15230-15239, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31479257

RESUMO

Catalysis is the second largest application for V after its use as an additive to improve steel production. Molecular complexes of vanadium(V) are particularly useful and efficient catalysts for oxidation processes; however, their ability to catalyze reductive transformations has yet to be fully explored. Here we report the first examples of polar organic functionality reduction mediated by V. Open-shell VIII complexes that feature a π-radical monoanionic 2,2':6',2″-terpyridine ligand (Rtpy•)- functionalized at the 4'-position (R = (CH3)3SiCH2, C6H5) catalyze mild and chemoselective hydroboration and hydrosilylation of functionalized ketones, aldehydes, imines, esters, and carboxamides with turnover numbers (TONs) of up to ∼1000 and turnover frequencies (TOFs) of up to ∼500 h-1. Computational evaluation of the precatalyst synthesis and activation has revealed underappreciated complexity associated with the redox-active tpy chelate.

16.
Opt Express ; 27(25): 36405-36413, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31873420

RESUMO

A suspended WO3-gate AlGaN/GaN heterostructure photodetector integrated with a micro-heater is micro-fabricated and characterized for ultraviolet photo detection. The transient optical characteristics of the photodetector at different temperatures are studied. The 2DEG-based photodetector shows a recovery (170 s) time under 240 nm illumination at 150 ℃. The measured spectral response of WO3-gate AlGaN/GaN heterostructure shows a high response in deep ultraviolet range. Responsivity at 240 nm wavelength is 4600 A/W at 0.5 V bias. These characteristics support the feasibility of a high accuracy deep UV detector based on the suspended AlGaN/GaN heterostructure integrated with a micro-heater.

17.
J Org Chem ; 84(10): 5987-5996, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31017441

RESUMO

Catalytic hydroboration of alkenes is a well-established method to access borane-functionalized hydrocarbons. While linear-selective hydroboration was predominantly reported, catalysts enabling opposite selectivity (branched-selective) are attracting considerable interest, especially when Earth-abundant metals are utilized. This Synopsis summarizes recent progress in Earth-abundant-metal-catalyzed, branched-selective hydroboration of alkenes while overviewing the historical contributions to this reaction using precious metals. Lessons learned from the current state of this topic that can guide future catalyst design are presented, along with challenging issues that remain to be addressed.

18.
Phys Chem Chem Phys ; 21(33): 18179-18187, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31389439

RESUMO

This paper presents the anti-corrosion application of polyvinylbutyral/tin sulfide (PVB/SnS) composites for the first time, where the liquid-phase exfoliated (LPE) SnS nanosheets are uniformly embedded in the PVB matrix. The measurement results of the potentiodynamic polarization, the electrochemical impedance spectroscopy (EIS) and the scanning electronic microscopy (SEM) show that PVB/SnS composite coatings show the excellent corrosion protection behavior for copper under 3.0% NaCl solution. Besides, we investigated the anti-corrosion performance with different contents of SnS nanosheets. The results show that embedding 0.1 wt% SnS nanosheets in the PVB matrix can greatly improve the anti-corrosion properties of the coating due to the enhanced "Labyrinth effect" of the coatings. In addition, the results of the molecular dynamic analysis further show the high interaction energy between PVB/SnS composites and copper, which is attributed to the high aspect-ratio of LPE-SnS nanosheets. Moreover, the scratch tests reveal that the PVB/SnS composite coatings exhibit weak corrosion-promotion activity, indicating a promising potential application in the corrosion protection of the metal surface for ocean engineering. The methods for enhancing the inhibited corrosion-promotion activity of the semiconductor material SnS-based composite coatings could be expanded to other n-type and p-type semiconductors.

19.
Phys Chem Chem Phys ; 21(27): 14713-14721, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31218307

RESUMO

In this study, the structural, electronic and optical properties of a tungsten disulfide (WS2) hybrid with indium-gallium-zinc-oxide (IGZO) heterostructures were investigated based on density functional theory (DFT) calculations. According to the results of binding energy, charge density difference and electron localization function of heterostructures, we found that the WS2 and IGZO monolayers were bound to each other via non-covalent interactions with large binding energy. The calculated results illustrate that the AAii stacking pattern has an indirect band gap of 1.643 eV, while AAi and AB stacking patterns have maximum direct-gaps of 1.102 eV and 1.234 eV, respectively. Under an external E-field and mechanical strain, the response of the energy gap of the WS2/IGZO heterostructure monotonically decreased over a wide range, even with a semiconductor-metal transition. In addition, we investigated the optical properties of the heterostructure and found that it exhibits a much broad spectral responsivity (from visible light to deep UV light) and a more pronounced optical absorption than WS2 and IGZO monolayers. Moreover, the tensile strain could weaken the photoresponse of the heterostructure to the UV light and enhance the response for the visible light; under compressive strain, the heterostructure showed a strong absorption peak in the UV light. Meanwhile, a red-shift was observed under an external strain. All these unique and tunable properties indicate that the WS2/IGZO heterostructure is a good candidate for nanoelectronic and photoelectronic devices, such as field-effect transistors, flexible sensors, photodetectors and photonic devices.

20.
J Org Chem ; 83(16): 9442-9448, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-29932672

RESUMO

Highly effective hydroboration precatalyst is developed based on a cobalt(II)-terpyridine coordination polymer (CP). The hydroboration of ketones, aldehydes, and imines with pinacolborane (HBpin) has been achieved using the recyclable CP catalyst in the presence of an air-stable activator. A wide range of substrates containing polar C═O or C═N bonds have been hydroborated selectively in excellent yields under ambient conditions.

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