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1.
Artigo em Inglês | MEDLINE | ID: mdl-38700962

RESUMO

In this paper, a high gain amplifier with phase compensation loop is presented. A structure of parallel gate cross-coupled transistors to both ends of differential pair drain and source is designed to improves the load impedance, which obtains sufficient gain and further reduces power consumption. A novel capacitor bootstrap load circuit is proposed. The capacitor bootstrap topology is constructed by the drain source resistance of the transistor working in the cut-off region, where the gate source parasitic capacitor of the transistor is in parallel with the bootstrap capacitor rather than the existing series structure, thereby only a small bootstrap capacitor is required. By avoiding the use of large capacitors, chip area can be effectively reduced without compromising performance such as gain and bandwidth. The amplifier is fabricated using 10-µm n-type a-IGZO TFT technology. Measurement results show that the proposed amplifier achieves a voltage gain of 43.5dB and a common mode rejection ratio of 61.2dB while maintaining low power consumption. The amplifier also exhibits a -3dB bandwidth covering 0.4~2.1KHz, encompassing major bioelectric frequency bands. A real-time ECG signal was successfully captured using the fabricated TFT amplifier and gel electrodes. It has great potential in flexible sensing and acquisition applications such as electro cardiogram (ECG), electro encephalogram (EEG), pulse detection, and other wearable applications.

2.
Nanoscale Adv ; 6(9): 2363-2370, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38694473

RESUMO

Herein, we report the successful fabrication of a series of transition metal doped Ni nanoparticles (NPs) coordinated with Ni single atoms in nitrogen-doped carbon nanotubes (denoted as Ni1+NPsM-NCNTs, M = Mn, Fe, Co, Cu and Zn; Ni1 = Ni single atom). X-ray absorption fine structure reveals the coexistence of Ni single atoms with Ni-N4 coordination and NiM NPs. When applied for electrocatalytic CO2RR, the Ni1+NPsM-NCNT compounds show the Faradaic efficiency of CO (FECO) with a volcano-like tendency of Mn < Fe ≈ Co < Zn < Cu, in which the Ni1+NPsCu-NCNT exhibits the highest FECO of 96.92%, a current density of 171.25 mA cm-2 and a sustainable stability over 24 hours at a current density of 100 mA cm-2, outperforming most reported examples in the literature. Detailed experiments and theoretical calculations reveal that for Ni1+NPsCu-NCNTs, the electron transfer from NiCu NPs to Ni single atoms strengthens the adsorption of *COOH intermediates. Moreover, the d-band center of Ni-N in Ni1+NPsCu-NCNT is upshifted, providing stronger binding with the reaction intermediates of *COOH, whereas the NiCu NPs increase the Gibbs free energy change of the Volmer step, suppressing the competitive HER.

3.
FASEB J ; 38(4): e23475, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38334450

RESUMO

Ankyrin-repeat proteins with a suppressor of cytokine signaling box (ASB) proteins belong to the E3 ubiquitin ligase family. 18 ASB members have been identified whose biological functions are mostly unexplored. Here, we discovered that ASB3 was essential for hepatocellular carcinoma (HCC) development and high ASB3 expression predicted poor clinical outcomes. ASB3 silencing induced HCC cell growth arrest and apoptosis in vitro and in vivo. Liver-specific deletion of Asb3 gene suppressed diethylnitrosamine (DEN)-induced liver cancer development. Mechanistically, ASB3 interacted with death receptor 5 (DR5), which promoted ubiquitination and degradation of DR5. We further showed that ASB3 knockdown stabilized DR5 and increased the sensitivity of liver cancer cells to the treatment of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in a DR5-dependent manner in cellular and in animal models. In summary, we demonstrated that ASB3 promoted ubiquitination and degradation of DR5 in HCC, suggesting the potential of targeting ASB3 to HCC treatment and overcome TRAIL resistance.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Apoptose , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Ligantes , Neoplasias Hepáticas/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitinação , Humanos
4.
Small ; : e2310857, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349039

RESUMO

Photocatalytic oxidative coupling of CH4 (OCM) is a promising CH4 conversion process that can achieve efficient methane conversion with the assistance of O2 . It remains to be highly challenging to improve the photocatalytic OCM activity from catalyst design and to deepen the understanding of the reactant activation in the OCM process. In this work, the Au-loaded ZnAl-layered double hydroxides (LDHs) with and without oxygen vacancy are constructed (denoted as Au/ZnAl and Au/ZnAl-v), respectively. When applied for photocatalytic OCM, the Au/ZnAl-v shows a CH4 conversion rate of 8.5 mmol g-1 h-1 with 92% selectivity of C2 H6 at 40 °C, outperforming most reported photocatalytic OCM systems at low temperature reported in the literature. Furthermore, the catalytic performance of Au/ZnAl-v can be stable for 100 h. In contrast, the An/ZnAl exhibits a CH4 conversion rate of 0.8 mmol g-1 h-1 with 46% selectivity of C2 H6 . Detailed characterizations and DFT calculation studies reveal that the introduced Ov sites on Au/ZnAl-v are able to activate O2 , and the resulting superoxide radical O2 ·- greatly promotes the activation of CH4 . The coupling of CH3 · groups with the assistance of Au cocatalyst leads to the formation of C2 H6 with high photocatalytic activity.

5.
Small ; 20(3): e2305539, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37699754

RESUMO

Artificial enzymes, as alternatives to natural enzymes, have attracted enormous attention in the fields of catalysis, biosensing, diagnostics, and therapeutics because of their high stability and low cost. Polyoxometalates (POMs), a class of inorganic metal oxides, have recently shown great potential in mimicking enzyme activity due to their well-defined structure, tunable composition, high catalytic efficiency, and easy storage properties. This review focuses on the recent advances in POM-based artificial enzymes. Different types of POMs and their derivatives-based mimetic enzyme functions are covered, as well as the corresponding catalytic mechanisms (where available). An overview of the broad applications of representative POM-based artificial enzymes from biosensing to theragnostic is provided. Insight into the current challenges and the future directions for POMs-based artificial enzymes is discussed.


Assuntos
Ânions , Polieletrólitos , Ânions/química , Polieletrólitos/química , Enzimas
6.
Small ; 20(19): e2307975, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38098446

RESUMO

Electrochemical methanol oxidation reaction (MOR) is regarded as a promising pathway to obtain value-added chemicals and drive cathodic H2 production, while the rational design of catalyst and in-depth understanding of the structure-activity relationship remains challenging. Herein, the ultrathin NiV-LDH (u-NiV-LDH) with abundant defects is successfully synthesized, and the defect-enriched structure is finely determined by X-ray adsorption fine structure etc. When applied for MOR, the as-prepared u-NiV-LDH presents a low potential of 1.41 V versus RHE at 100 mA cm-2, which is much lower than that of bulk NiV-LDH (1.75 V vs RHE) at the same current density. The yield of H2 and formate is 98.2% and 88.1% as its initial over five cycles and the ultrathin structure of u-NiV-LDH can be well maintained. Various operando experiments and theoretical calculations prove that the few-layer stacking structure makes u-NiV-LDH free from the interlayer hydrogen diffusion process and the hydrogen can be directly detached from LDH laminate. Moreover, the abundant surface defects upshift the d-band center of u-NiV-LDH and endow a higher local methanol concentration, resulting in an accelerated dehydrogenation kinetics on u-NiV-LDH. The synergy of the proton detachment from the laminate and the methanol dehydrogenation oxidation contributes to the excellent MOR performance of u-NiV-LDH.

7.
RSC Adv ; 13(51): 36254-36260, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38090074

RESUMO

The level of heat resistance in microbial cells is an important factor in determining the energy consumption and product synthesis efficiency of fermentation processes. Current research generally believes that heat shock proteins (HSPs) are the most closely related functional molecules to heat resistance inside cells. They can stabilize cell structures and allow cells to perform their normal physiological functions. Based on our previous transcriptome data, this study applies synthetic biology methods to validate the functionality of heat-resistant elements. The researchers introduced gene circuits expressing small HSPs (sHSP-HB8, HSP12, HSP26, HSP30, HSP42, and ibpa-MB4) with different promoter strengths (TDH3p, YNL247wp) into Saccharomyces cerevisiae strains for functional verification. All engineered strains, with the exception of No. 3 and No. 8, demonstrated a significantly higher growth rate and cell viability at 42 °C. Among them, No. 7 (YNL247wp-HSP12-SLM5t) and No. 11 (YNL247wp-sHSP-HB8-SLM5t), the two best performing engineered strains, exhibited a 19.8% and 17.2% increase in cell density, respectively, compared to the control strain. Additionally, the analysis of pyruvate kinase (PK) and malate dehydrogenase (MDH) enzyme activities indicated that the engineered strains enhanced protein quality at higher temperatures. The research methods and ideas presented in this paper have significant scientific reference value for exploring and applying other stress-resistant gene circuits.

8.
Micromachines (Basel) ; 14(12)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38138413

RESUMO

A low-power SAR ADC with capacitor-splitting energy-efficient switching scheme is proposed for wearable biosensor applications. Based on capacitor-splitting, additional reference voltage Vcm, and common-mode techniques, the proposed switching scheme achieves 93.76% less switching energy compared to the conventional scheme with common-mode voltage shift in one LSB. With the switching scheme, the proposed SAR ADC can lower the dependency on the accuracy of Vcm and the complexity of digital control logic and DAC driver circuits. Furthermore, the SAR ADC employs low-noise and low-power dynamic comparators utilizing multi-clock control, low sampling error sampling switches based on the bootstrap technique, and dynamic SAR logic. The simulation results demonstrate that the ADC achieves a 61.77 dB SNDR and a 78.06 dB SFDR and consumes 4.45 µW of power in a 180 nm process with a 1 V power supply, a full-swing input signal frequency of 93.33 kHz, and a sampling rate of 200 kS/s.

9.
Appl Opt ; 62(28): 7544-7548, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855525

RESUMO

In a stretcher, the surface distortion of the optical elements can introduce spectral phase modulations into the laser, which can affect the laser's signal-to-noise ratio. In this paper, by combining ray tracing methods and angular spectrum diffraction methods, the impact of the mid-frequency surface distortion of the optical elements in an cylindrical Offner stretcher on the far-field signal-to-noise ratio of the laser is simulated. The results show that reducing the spatial chirp on the convex cylindrical mirror can effectively improve the far-field signal-to-noise ratio of the laser, and two methods to improve the far-field signal-to-noise ratio are presented.

10.
ACS Appl Mater Interfaces ; 15(39): 45764-45773, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37726198

RESUMO

Li metal batteries applying Li-rich, Mn-rich (LMR) layered oxide cathodes present an opportunity to achieve high-energy density at reduced cell cost. However, the intense oxidizing and reducing potentials associated with LMR cathodes and Li anodes present considerable design challenges for prospective electrolytes. Herein, we demonstrate that, somewhat surprisingly, a properly designed localized-high-concentration electrolyte (LHCE) based on ether solvents is capable of providing reversible performance for Li||LMR cells. Specifically, the oxidative stability of the LHCE was found to heavily rely on the ratio between salt and solvating solvent, where local-saturation was necessary to stabilize performance. Through molecular dynamics (MD) simulations, this behavior was found to be a result of aggregated solvation structures of Li+/anion pairs. This LHCE system was found to produce significantly improved LMR cycling (95.8% capacity retention after 100 cycles) relative to a carbonate control as a result of improved cathode-electrolyte interphase (CEI) chemistry from X-ray photoelectron spectroscopy (XPS), and cryogenic transmission electron microscopy (cryo-TEM). Leveraging this stability, 4 mAh cm-2 LMR||2× Li full cells were demonstrated, retaining 87% capacity after 80 cycles in LHCE, whereas the control electrolyte produced rapid failure. This work uncovers the benefits, design requirements, and performance origins of LHCE electrolytes for high-voltage Li||LMR batteries.

11.
Small ; 19(50): e2304604, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37635099

RESUMO

Selective conversion of ethane (C2 H6 ) to high-value-added chemicals is a very important chemical process, yet it remains challenging owing to the difficulty of ethane activation. Here, a NiTi-layered double hydroxide (NiTi-LDH) photocatalyst is reported for oxidative coupling of ethane to n-butane (n-C4 H10 ) by using CO2 as an oxidant. Remarkably, the as-prepared NiTi-LDH exhibits a high selectivity for n-C4 H10 (92.35%) with a production rate of 62.06 µmol g-1 h-1 when the feed gas (CO2 /C2 H6 ) ratio is 2:8. The X-ray absorption fine structure (XAFS) and photoelectron characterizations demonstrate that NiTi-LDH possesses rich vacancies and high electron-hole separation efficiency, which can promote the coupling of C2 H6 to n-C4 H10 . More importantly, density functional theory (DFT) calculations reveal that ethane is first activated on the oxygen vacancies of the catalyst surface, and the C─C coupling pathway is more favorable than the C─H cleavage to C2 H4 or CH4 , resulting in the high production rate and selectivity for n-C4 H10 .

12.
J Am Chem Soc ; 145(17): 9624-9633, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37071778

RESUMO

Sulfurized polyacrylonitrile (SPAN) represents a class of sulfur-bonded polymers, which have shown thousands of stable cycles as a cathode in lithium-sulfur batteries. However, the exact molecular structure and its electrochemical reaction mechanism remain unclear. Most significantly, SPAN shows an over 25% 1st cycle irreversible capacity loss before exhibiting perfect reversibility for subsequent cycles. Here, with a SPAN thin-film platform and an array of analytical tools, we show that the SPAN capacity loss is associated with intramolecular dehydrogenation along with the loss of sulfur. This results in an increase in the aromaticity of the structure, which is corroborated by a >100× increase in electronic conductivity. We also discovered that the conductive carbon additive in the cathode is instrumental in driving the reaction to completion. Based on the proposed mechanism, we have developed a synthesis procedure to eliminate more than 50% of the irreversible capacity loss. Our insights into the reaction mechanism provide a blueprint for the design of high-performance sulfurized polymer cathode materials.

13.
Chemistry ; 29(37): e202300050, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37043334

RESUMO

Layered double hydroxides (LDHs) have shown great potential as adsorbents for the removal of heavy metals. Nevertheless, how the host-guest interactions of LDHs affect the removal mechanism remains to be less explored. Herein, CO3 2- /NO3 - /SO4 2- /Cl- intercalated MgAl-LDHs with different host-guest interactions were fabricated and their removal mechanism for Cd2+ was investigated. The removal capacity increased in the order of MgAl-CO3 (127.3 mg/g)

14.
Small ; 19(21): e2300581, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36823447

RESUMO

Electrocatalytic reduction of CO2 to high-value-added chemicals provides a feasible path for global carbon balance. Herein, the fabrication of NiNP x @NiSA y -NG (x,y = 1, 2, 3; NG = nitrogen-doped graphite) is reported, in which Ni single atom sites (NiSA ) and Ni nanoparticles (NiNP ) coexist. These NiNP x @NiSA y -NG presented a volcano-like trend for maximum CO Faradaic efficiency (FECO ) with the highest point at NiNP2 @NiSA2 -NG in CO2 RR. NiNP2 @NiSA2 -NG exhibited ≈98% of maximum FECO and a large current density of -264 mA cm-2 at -0.98 V (vs. RHE) in the flow cell. In situ experiment and density functional theory (DFT) calculations confirmed that the proper content of NiSA and NiNP balanced kinetic between proton-feeding and CO2 hydrogenation. The NiNP in NiNP2 @NiSA2 -NG promoted the formation of H* and reduced the energy barrier of *CO2 hydrogenation to *COOH, and CO desorption can be efficiently facilitated by NiSA sites, thereby resulting in enhanced CO2 RR performance.

15.
Micromachines (Basel) ; 15(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38258179

RESUMO

A hybrid energy-efficient, area-efficient, low-complexity switching scheme in SAR ADC for biosensor applications is proposed. This scheme is a combination of the monotonic technique, the MSB capacitor-splitting technique, and a new switching method. The MSB capacitor-splitting technique, as well as the reference voltage Vaq allow for more options for reference voltage conversion, resulting in higher area savings and higher energy efficiency. In a capacitor array, the circuit performs unilateral switching during all comparisons except for the second and last two comparisons, reducing the difficulty in designing the drive circuit. The proposed switching scheme saves 98.4% of the switching energy and reduces the number of unit capacitors by 87.5% compared to a conventional scheme. Furthermore, the SAR ADC employs low-noise and low-power dynamic comparators utilizing multi-clock control, low-sampling error-sampling switches based on the bootstrap technique, and dynamic SAR logic. The simulation results demonstrated that the proposed SAR ADC achieves 61.51 dB SNDR, 79.21 dB SFDR and consumes 0.278 µW of power in a 180 nm process with a 1 V power supply, a full swing input signal frequency of 23.33 kHz, and a sampling rate of 100 kS/s.

16.
Micromachines (Basel) ; 13(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36557409

RESUMO

This paper presents a 10-bit successive approximation register analog-to-digital converter with energy-efficient low-complexity switching scheme, automatic ON/OFF comparator and automatic ON/OFF SAR logic for biomedical applications. The energy-efficient switching scheme achieves an average digital-to-analog converter switching energy of 63.56 CVref2, achieving a reduction of 95.34% compared with the conventional capacitor switching scheme for CDACs. With the switching scheme, the ADC can lower the dependency on the accuracy of Vcm and complexity of DAC control logic and DAC driver circuit. Moreover, dynamic circuits and automatic ON/OFF technology are used to reduce power consumption of comparator and SAR logic. The prototype is designed and fabricated in a 180 nm CMOS with a core size of 500 µm × 300 µm (0.15 mm2). It consumes 7.6 nW at 1 kS/s sampling rate and 1.8-V supply with an achieved signal-to-noise-and distortion ratio of 45.90 dB and a resulting figure of merit of 51.7 fJ/conv.-step.

17.
ACS Appl Mater Interfaces ; 14(46): 52046-52057, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36377408

RESUMO

Sulfurized polyacrylonitrile (SPAN) represents one of the most promising directions for high-energy-density lithium (Li)-sulfur batteries. However, the practical application of Li||SPAN is currently limited by the insufficient chemical/electrochemical stability of electrode/electrolyte interphase (EEI). Here, a pinned EEI layer is designed for stabilizing a SPAN cathode by regulating the EEI formation mechanism in an advanced LiFSI/ether/fluorinated-ether electrolyte. Computational simulations and experimental investigations reveal that, benefiting from the nonsolvating nature, the fluorinated-ether can not only act as a protective shield to prevent the Li polysulfides dissolution but also, more importantly, endow a diffusion-controlled EEI formation process. It promotes the formation of a uniform, protective, and conductive EEI layer pinning into SPAN surface region, enabling the high loading Li||SPAN batteries with superior cycling stability, wide temperature performance, and high-rate capability. This design strategy opens an avenue for exploring advanced electrolytes for Li||SPAN batteries and guides the interface design for broad types of battery systems.

18.
Micromachines (Basel) ; 13(11)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36363934

RESUMO

A DAC switching scheme that combines energy efficiency and resolution reconfigurability is proposed. Compared with the conventional switching scheme, the proposed scheme achieves 93.8%, 96.1%, and 97.3% switching energy saving in 8-bit, 9-bit, and 10-bit modes, respectively. Based on the proposed switching scheme, an 8-10-bit resolution-reconfigurable SAR ADC for biosensor applications is designed. The ADC consists of resolution-reconfigurable binary-weighted capacitive DAC, a two-stage full dynamic comparator, sampling switch, and the resolution-control SAR logic. Simulated in 180 nm CMOS process and 100 kS/s sampling rate, the ADC achieves the 46.80/53.89/60.14 dB signal-to-noise and distortion ratio (SNDR), the 55.22/62.51/73.09 dB spurious-free dynamic range (SFDR) and the 0.81/0.91/1.01 µW power consumption in 8/9/10-bit mode, respectively.

19.
Opt Express ; 30(13): 23556-23567, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36225032

RESUMO

Optical solitons in mode-locked laser cavities with dispersion-nonlinearity interaction, delivers pulses of light that retain their shape. Due to the nature of discretely distributed dispersion and nonlinearity, optical solitons can emit Kelly-sidebands via the frequency coupling of soliton and dispersive waves. In this paper, we generate a high-energy femtosecond laser comb, by using the intracavity Kelly radiations and 3rd order nonlinearities. By increasing the intracavity power, the soliton envelop and the Kelly-sidebands merge together via four-wave-mixing, forming a super-continuum spectrum, obtaining 3.18 nJ pulse energy. A supercontinuum span covering from 1100 nm to 2300 nm for further self-referenced f-2f stabilization can be directly achieved by using an amplification-free external supercontinuum technique. Our finding not only demonstrates a non-trivial frequency-time evolution based on 'erbium + χ(3)' nonlinear gains, but also offers a new opportunity to develop practically compact fiber frequency combs for frequency metrology or spectroscopy.

20.
ACS Appl Mater Interfaces ; 14(40): 45423-45432, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36190016

RESUMO

The electrocatalytic reduction of CO2 is deemed to be a promising method to ease environmental and energy issues. However, achieving high efficiency and selectivity of CO2 electroreduction remains a bottleneck due to huge limitation of CO2 mass transfer and competition of hydrogen evolution reaction (HER) in aqueous solution. In this work, we propose to utilize triple-phase interface engineering over an In2O3 electrode to enhance its CO2 reduction reaction (CO2RR) performance. Notably, distinguishing from other research studies (doping, defect introduction, and heterojunction construction) that regulate the nature of In2O3-based catalysts themselves, we herein tune interfacial wettability of In2O3 using facile fluoropolymer coating for the first time. In contrast to the hydrophilic In2O3 electrode [Faraday efficiency (FE)HCOOH ∼ 62.7% and FEH2 ∼ 24.1% at -0.67 V versus RHE], the hydrophobic fluoropolymer (taking polyvinylidene fluoride as an example)-coated In2O3 electrode delivers a significantly enhanced FEHCOOH of 82.3% and a decreased FEH2 of 5.7% at the same potential. Upon combining contact angle measurements, density functional theory calculation, and ab initio molecular dynamics simulation, the enhanced CO2RR performance is revealed to be attributed to the rich triple-phase interfaces formed after fluoropolymer coating as an "aerophilic sponge", which increases the local concentration of CO2 near In2O3 active sites to improve CO2 reduction and meanwhile reduces the accessible water molecules to suppress competitive HER. This work presents a feasible approach for the enhanced selectivity of HCOOH yield over In2O3 by triple-phase interface engineering, which also provides a convenient and effective method for developing other materials used in gas-consumption reactions.

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