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1.
Nature ; 622(7984): 748-753, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37704734

RESUMO

Stimulus-responsive shape-shifting polymers1-3 have shown unique promise in emerging applications, including soft robotics4-7, medical devices8, aerospace structures9 and flexible electronics10. Their externally triggered shape-shifting behaviour offers on-demand controllability essential for many device applications. Ironically, accessing external triggers (for example, heating or light) under realistic scenarios has become the greatest bottleneck in demanding applications such as implantable medical devices8. Certain shape-shifting polymers rely on naturally present stimuli (for example, human body temperature for implantable devices)8 as triggers. Although they forgo the need for external stimulation, the ability to control recovery onset is also lost. Naturally triggered, yet actively controllable, shape-shifting behaviour is highly desirable but these two attributes are conflicting. Here we achieved this goal with a four-dimensional printable shape memory hydrogel that operates via phase separation, with its shape-shifting kinetics dominated by internal mass diffusion rather than by heat transport used for common shape memory polymers8-11. This hydrogel can undergo shape transformation at natural ambient temperature, critically with a recovery onset delay. This delay is programmable by altering the degree of phase separation during device programming, which offers a unique mechanism for shape-shifting control. Our naturally triggered shape memory polymer with a tunable recovery onset markedly lowers the barrier for device implementation.

2.
Nature ; 610(7930): 67-73, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36131017

RESUMO

The high volatility of the price of cobalt and the geopolitical limitations of cobalt mining have made the elimination of Co a pressing need for the automotive industry1. Owing to their high energy density and low-cost advantages, high-Ni and low-Co or Co-free (zero-Co) layered cathodes have become the most promising cathodes for next-generation lithium-ion batteries2,3. However, current high-Ni cathode materials, without exception, suffer severely from their intrinsic thermal and chemo-mechanical instabilities and insufficient cycle life. Here, by using a new compositionally complex (high-entropy) doping strategy, we successfully fabricate a high-Ni, zero-Co layered cathode that has extremely high thermal and cycling stability. Combining X-ray diffraction, transmission electron microscopy and nanotomography, we find that the cathode exhibits nearly zero volumetric change over a wide electrochemical window, resulting in greatly reduced lattice defects and local strain-induced cracks. In-situ heating experiments reveal that the thermal stability of the new cathode is significantly improved, reaching the level of the ultra-stable NMC-532. Owing to the considerably increased thermal stability and the zero volumetric change, it exhibits greatly improved capacity retention. This work, by resolving the long-standing safety and stability concerns for high-Ni, zero-Co cathode materials, offers a commercially viable cathode for safe, long-life lithium-ion batteries and a universal strategy for suppressing strain and phase transformation in intercalation electrodes.

3.
Nano Lett ; 24(18): 5429-5435, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38682885

RESUMO

Realizing room-temperature, efficient, and reversible fluoride-ion redox is critical to commercializing the fluoride-ion battery, a promising post-lithium-ion battery technology. However, this is challenging due to the absence of usable electrolytes, which usually suffer from insufficient ionic conductivity and poor (electro)chemical stability. Herein we report a water-in-salt (WIS) electrolyte based on the tetramethylammonium fluoride salt, an organic salt consisting of hydrophobic cations and hydrophilic anions. The new WIS electrolyte exhibits an electrochemical stability window of 2.47 V (2.08-4.55 V vs Li+/Li) with a room-temperature ionic conductivity of 30.6 mS/cm and a fluoride-ion transference number of 0.479, enabling reversible (de)fluoridation redox of lead and copper fluoride electrodes. The relationship between the salt property, the solvation structure, and the ionic transport behavior is jointly revealed by computational simulations and spectroscopic analysis.

4.
Neuroimage ; 289: 120551, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382862

RESUMO

It has been revealed that abnormal voxel-mirrored homotopic connectivity (VMHC) is present in patients with schizophrenia, yet there are inconsistencies in the relevant findings. Moreover, little is known about their association with brain gene expression profiles. In this study, transcription-neuroimaging association analyses using gene expression data from Allen Human Brain Atlas and case-control VMHC differences from both the discovery (meta-analysis, including 9 studies with a total of 386 patients and 357 controls) and replication (separate group-level comparisons within two datasets, including a total of 258 patients and 287 controls) phases were performed to identify genes associated with VMHC alterations. Enrichment analyses were conducted to characterize the biological functions and specific expression of identified genes, and Neurosynth decoding analysis was performed to examine the correlation between cognitive-related processes and VMHC alterations in schizophrenia. In the discovery and replication phases, patients with schizophrenia exhibited consistent VMHC changes compared to controls, which were correlated with a series of cognitive-related processes; meta-regression analysis revealed that illness duration was negatively correlated with VMHC abnormalities in the cerebellum and postcentral/precentral gyrus. The abnormal VMHC patterns were stably correlated with 1287 genes enriched for fundamental biological processes like regulation of cell communication, nervous system development, and cell communication. In addition, these genes were overexpressed in astrocytes and immune cells, enriched in extensive cortical regions and wide developmental time windows. The present findings may contribute to a more comprehensive understanding of the molecular mechanisms underlying VMHC alterations in patients with schizophrenia.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/genética , Imageamento por Ressonância Magnética , Encéfalo , Mapeamento Encefálico , Expressão Gênica
5.
J Am Chem Soc ; 146(26): 17712-17718, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38874441

RESUMO

The ever-increasing demand for safety has thrust all-solid-state batteries (ASSBs) into the forefront of next-generation energy storage technologies. However, the atomic mechanisms underlying the failure of layered cathodes in ASSBs, as opposed to their counterparts in liquid electrolyte-based lithium-ion batteries (LIBs), have remained elusive. Here, leveraging artificial intelligence-enhanced super-resolution electron microscopy, we unravel the atomic origins dictating the chemomechanical degradation of technologically crucial high-Ni layered oxide cathodes in ASSBs. We reveal that the coupling of surface frustration and interlayer-shear-induced phase transformation exacerbates the chemomechanical breakdown of layered cathodes. Surface frustration, a phenomenon previously unobserved in liquid electrolyte-based LIBs, emerges through electrochemical processes involving surface nanocrystallization coupled with rock salt transformation. Simultaneously, delithiation-induced interlayer shear yields the formation of chunky O1 phases and intricate interfaces/transition motifs, distinct from scenarios observed in liquid electrolyte-based LIBs. Bridging the knowledge gap between the failure mechanisms of layered cathodes in solid-state electrolytes and conventional liquid electrolytes, our study provides unprecedented atomic-scale insights into the degradation pathways of layered cathodes in ASSBs.

6.
Oncologist ; 29(9): e1189-e1200, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-38982653

RESUMO

BACKGROUND AND OBJECTIVES: Envafolimab is the first and only globally approved subcutaneously injectable PD-L1 antibody for the treatment of instability-high (MSI-H) or DNA mismatch repair deficient (dMMR) advanced solid tumors in adults, including those with advanced colorectal cancer that has progressed after treatment with a fluoropyrimidine, oxaliplatin, and irinotecan. The aim of this investigation was to examine the pharmacokinetic and exposure-response (E-R) profile of envafolimab in patients with solid tumors to support the approval of fixed and alternative dose regimens. METHODS: In this study, a population pharmacokinetic (PopPK) modeling approach will be employed to quantitatively evaluate intrinsic and extrinsic covariates. Additionally, PopPK-estimated exposure parameters were used to evaluate E-R relationship for safety and efficacy to provide a theoretical basis for recommending optimal treatment regimens. Simulations were performed on the dosing regimens of body weight-based regimen of 2.50 mg/kg QW, fixed dose 150 mg QW, and 300 mg Q2W for the selection of alternative dosing regimens. Data from 4 clinical studies (NCT02827968, NCT03101488, NCT03248843, and NCT03667170) were utilized. RESULTS: The PopPK dataset comprised 182 patients with 1810 evaluable envafolimab concentration records. Finally, a one-compartment model incorporating first-order absorption, first-order linear elimination, and time-dependent elimination according to an Emax function was found to accurately describe the concentration-time data of envafolimab in patients with advanced solid tumors. Creatinine clearance and country were identified as statistically significant factors affecting clearance, but had limited clinical significance. A relative flat exposure-response relationship was observed between early measures of safety and efficacy to verify that no dose adjustment is required. Simulation results indicated that 2.50 mg/kg QW, 150 mg QW, and 300 mg Q2W regimen yield similar steady-state exposure. CONCLUSIONS: No statistically significant difference was observed between weight-based and fixed dose regimens. Model-based simulation supports the adoption of a 150 mg weekly or 300 mg biweekly dosing regimen of envafolimab in the solid tumor population, as these schedules effectively balance survival benefits and safety risks.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Injeções Subcutâneas , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Antígeno B7-H1/antagonistas & inibidores , Idoso , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacocinética
7.
Nat Mater ; 22(2): 235-241, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36702885

RESUMO

High-Ni-content layered materials are promising cathodes for next-generation lithium-ion batteries. However, investigating the atomic configurations of the delithiation-induced complex phase boundaries and their transitions remains challenging. Here, by using deep-learning-aided super-resolution electron microscopy, we resolve the intralayer transition motifs at complex phase boundaries in high-Ni cathodes. We reveal that an O3 → O1 transformation driven by delithiation leads to the formation of two types of O1-O3 interface, the continuous- and abrupt-transition interfaces. The interfacial misfit is accommodated by a continuous shear-transition zone and an abrupt structural unit, respectively. Atomic-scale simulations show that uneven in-plane Li+ distribution contributes to the formation of both types of interface, and the abrupt transition is energetically more favourable in a delithiated state where O1 is dominant, or when there is an uneven in-plane Li+ distribution in a delithiated O3 lattice. Moreover, a twin-like motif that introduces structural units analogous to the abrupt-type O1-O3 interface is also uncovered. The structural transition motifs resolved in this study provide further understanding of shear-induced phase transformations and phase boundaries in high-Ni layered cathodes.

8.
J Org Chem ; 89(11): 7521-7530, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38753574

RESUMO

This study reports a protocol for the highly regioselective photocatalyzed C-H nitrosylation of imidazo[1,2-a]pyridine scaffolds at the C3 position under a combination of visible-light irradiation and continuous flow without any external photocatalyst. This protocol involves mild and safe conditions and shows good tolerance to air and water along with excellent functional group compatibility and site selectivity, generating various 3-nitrosoimidazo[1,2-a]pyridines in excellent yields under photocatalyst-, oxidant-, and additive-free conditions.Notably, the proposed nitrosylation reaction, which introduces the chromophore NO into imidazo[1,2-a]pyridine scaffolds, occurs efficiently under visible-light irradiation without any additional photocatalyst owing to the intense light-absorption characteristics of the nitrosylation products. This study could guide future studies on the development of green organic-synthesis strategies with a wide variety of potential applications.

9.
Appl Opt ; 63(10): 2570-2577, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568538

RESUMO

The limited excitation efficiency of quantum dots in the detection of subsurface defects in optical elements by quantum dot fluorescence gives rise to insufficient accuracy. To enhance the excitation efficiency of quantum dots, we studied the modulation of the polarization direction of linearly polarized incident light on quantum dot fluorescence. We first apply density matrix evolution theory to study the quantum dots interacting with linearly polarized incident light and emitting fluorescence. The fluorescence intensity exhibits cosine oscillations versus modulated laser polarization. It reaches a maximum value at the polarization angle zero, and then decreases as the angle becomes larger until π/2. The experimental results for the quantum dot in both solutions and subsurface defect of optical elements confirmed these results. For optical elements tagged with CdSe/ZnS quantum dots, the fluorescence intensity increases by 61.7%, and the area for the detected subsurface defects increases by 142.9%. Similarly, for C and InP/ZnS quantum dots, there are also increases in both the fluorescence intensity and the area of subsurface defects. Our study suggests that the subsurface defect detection in optical elements by the linearly polarized incident light could enhance the detection accuracy of subsurface defects in optical elements, and potentially achieve super-resolution imaging of subsurface defects.

10.
Nano Lett ; 23(17): 8272-8279, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37643420

RESUMO

Phase transformation─a universal phenomenon in materials─plays a key role in determining their properties. Resolving complex phase domains in materials is critical to fostering a new fundamental understanding that facilitates new material development. So far, although conventional classification strategies such as order-parameter methods have been developed to distinguish remarkably disparate phases, highly accurate and efficient phase segmentation for material systems composed of multiphases remains unavailable. Here, by coupling hard-attention-enhanced U-Net network and geometry simulation with atomic-resolution transmission electron microscopy, we successfully developed a deep-learning tool enabling automated atom-by-atom phase segmentation of intertwined phase domains in technologically important cathode materials for lithium-ion batteries. The new strategy outperforms traditional methods and quantitatively elucidates the correlation between the multiple phases formed during battery operation. Our work demonstrates how deep learning can be employed to foster an in-depth understanding of phase transformation-related key issues in complex materials.

11.
Angew Chem Int Ed Engl ; 63(14): e202319427, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38355900

RESUMO

Solid polymer electrolytes based on plastic crystals are promising for solid-state sodium metal (Na0) batteries, yet their practicality has been hindered by the notorious Na0-electrolyte interface instability issue, the underlying cause of which remains poorly understood. Here, by leveraging a model plasticized polymer electrolyte based on conventional succinonitrile plastic crystals, we uncover its failure origin in Na0 batteries is associated with the formation of a thick and non-uniform solid electrolyte interphase (SEI) and whiskery Na0 nucleation/growth. Furthermore, we design a new additive-embedded plasticized polymer electrolyte to manipulate the Na0 deposition and SEI formulation. For the first time, we demonstrate that introducing fluoroethylene carbonate (FEC) additive into the succinonitrile-plasticized polymer electrolyte can effectively protect Na0 against interfacial corrosion by facilitating the growth of dome-like Na0 with thin, amorphous, and fluorine-rich SEIs, thus enabling significantly improved performances of Na//Na symmetric cells (1,800 h at 0.5 mA cm-2) and Na//Na3V2(PO4)3 full cells (93.0 % capacity retention after 1,200 cycles at 1 C rate in coin cells and 93.1 % capacity retention after 250 cycles at C/3 in pouch cells at room temperature). Our work provides valuable insights into the interfacial failure of plasticized polymer electrolytes and offers a promising solution to resolving the interfacial instability issue.

12.
Langmuir ; 39(25): 8769-8778, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37307594

RESUMO

Incorporating inorganic components into organic molecular devices offers one novel alternative to address challenges existing in the fabrication and integration of nanoscale devices. In this study, using a theoretical method of density functional theory combined with the nonequilibrium Green's function, a series of benzene-based molecules with group III and V substitutions, including borazine molecule and XnB3-nN3H6 (X = Al or Ga, n = 1-3) molecules/clusters, are constructed and investigated. An analysis of electronic structures reveals that the introduction of inorganic components effectively reduces the energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, albeit at the cost of reduced aromaticity in these molecules/clusters. Simulated electronic transport characteristics demonstrate that XnB3-nN3H6 molecules/clusters coupled between metal electrodes exhibit lower conductance compared to prototypical benzene molecule. Additionally, the choice of metal electrode materials significantly impacts the electronic transport properties, with platinum electrode devices displaying distinct behavior compared to silver, copper, and gold electrode devices. This distinction arises from the amount of transferred charge, which modulates the alignment between molecular orbitals and the Fermi level of the metal electrodes by shifting the molecular orbitals in energy. These findings provide valuable theoretical insights for the future design of molecular devices incorporating inorganic substitutions.

13.
Chem Rev ; 121(10): 5986-6056, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33861070

RESUMO

Lithium (Li) metal, a typical alkaline metal, has been hailed as the "holy grail" anode material for next generation batteries owing to its high theoretical capacity and low redox reaction potential. However, the uncontrolled Li plating/stripping issue of Li metal anodes, associated with polymorphous Li formation, "dead Li" accumulation, poor Coulombic efficiency, inferior cyclic stability, and hazardous safety risks (such as explosion), remains as one major roadblock for their practical applications. In principle, polymorphous Li deposits on Li metal anodes includes smooth Li (film-like Li) and a group of irregularly patterned Li (e.g., whisker-like Li (Li whiskers), moss-like Li (Li mosses), tree-like Li (Li dendrites), and their combinations). The nucleation and growth of these Li polymorphs are dominantly dependent on multiphysical fields, involving the ionic concentration field, electric field, stress field, and temperature field, etc. This review provides a clear picture and in-depth discussion on the classification and initiation/growth mechanisms of polymorphous Li from the new perspective of multiphysical fields, particularly for irregular Li patterns. Specifically, we discuss the impact of multiphysical fields' distribution and intensity on Li plating behavior as well as their connection with the electrochemical and metallurgical properties of Li metal and some other factors (e.g., electrolyte composition, solid electrolyte interphase (SEI) layer, and initial nuclei states). Accordingly, the studies on the progress for delaying/suppressing/redirecting irregular Li evolution to enhance the stability and safety performance of Li metal batteries are reviewed, which are also categorized based on the multiphysical fields. Finally, an overview of the existing challenges and the future development directions of metal anodes are summarized and prospected.

14.
BMC Cardiovasc Disord ; 23(1): 97, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36809978

RESUMO

BACKGROUND AND OBJECTIVE: Protease-activated receptor 1 (PAR1) is crucial in individuals with acute myocardial infarction (AMI). The continuous and prompt PAR1 activation mainly dependent on PAR1 trafficking is essential for the role of PAR1 during AMI in which cardiomyocytes are in hypoxia. However, the PAR1 trafficking in cardiomyocytes specially during the hypoxia is still unclear. METHODS AND RESULT: A rat AMI model was created. PAR1 activation with thrombin-receptor activated peptide (TRAP) had a transient effect on cardiac function in normal rats but persistent improvement in rats with AMI. Cardiomyocytes from neonatal rats were cultured in a normal CO2 incubator and a hypoxic modular incubator chamber. The cells were then subjected to western blot for the total protein expression and staining with fluorescent reagent and antibody for PAR1 localization. No change in total PAR1 expression following TRAP stimulation was observed; however, it led to increased PAR1 expression in the early endosomes in normoxic cells and decreased expression in the early endosomes in hypoxic cells. Under hypoxic conditions, TRAP restored the PAR1 expression on both cell and endosomal surfaces within an hour by decreasing Rab11A (8.5-fold; 179.93 ± 9.82% of the normoxic control group, n = 5) and increasing Rab11B (15.5-fold) expression after 4 h of hypoxia. Similarly, Rab11A knockdown upregulated PAR1 expression under normoxia, and Rab11B knockdown downregulated PAR1 expression under both normoxic and hypoxic conditions. Cardiomyocytes knocked out of both Rab11A, and Rad11B lost the TRAP-induced PAR1 expression but still exhibited the early endosomal TRAP-induced PAR1 expression under hypoxia. CONCLUSIONS: TRAP-mediated activation of PAR1 in cardiomyocytes did not alter the total PAR1 expression under normoxic conditions. Instead, it triggers a redistribution of PAR1 levels under normoxic and hypoxic conditions. TRAP reverses the hypoxia-inhibited PAR1 expression in cardiomyocytes by downregulating Rab11A expression and upregulating Rab11B expression.


Assuntos
Infarto do Miocárdio , Receptor PAR-1 , Animais , Ratos , Hipóxia/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Peptídeos/metabolismo , Peptídeos/farmacologia , Receptor PAR-1/metabolismo , Receptores de Trombina/metabolismo , Trombina/metabolismo , Trombina/farmacologia
15.
Appl Opt ; 62(27): 7263-7269, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37855583

RESUMO

The use of the fast steering mirror in an optical path requires strict volume control, and traditional structures have low space-utilization efficiency, resulting in traditional actuators having limited output in narrow spaces. The design in this paper adopts a combination of flexible universal supports and piezoelectric ceramic actuators, greatly reducing the layout space of the rotating-shaft system. We accurately model the design structure and develop closed-loop control methods to further improve the closed-loop control accuracy of the system. The experimental results indicate that the developed control method effectively improves the response speed and bandwidth and thus has good potential for use in engineering applications.

16.
Urol Int ; 107(10-12): 943-948, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37967543

RESUMO

BACKGROUND AND OBJECTIVE: Distal ureter management is an essential part of radical nephroureterectomy (RNU). However, there is no agreement on the optimal surgical treatment for ureter and bladder cuff excision. The classical "pluck" technique following transurethral resection of the intramural ureter increases the risk of extravesical and intravesical tumor cell spillage. We aimed to provide a simple transurethral technique with the Hem-o-lok clip ligation for the management of the distal ureter during retroperitoneal laparoscopic RNU. METHODS: Transurethral resection of the bladder cuff was performed using a bipolar ß electrode mounted on resectoscope. Subsequently, a Super Scope (S-scope) with a 5.6-mm diameter working channel was used with a clip applier to deliver the 5-mm Hem-o-lok clips, which consequently ligated the ureteral stump and avoided urine spillage from the upper tract. Traditional retroperitoneal laparoscopic surgery was used to treat the renal and upper ureter. The resected distal ureter and the Hem-o-lok clip were gently pulled out of the bladder by the "pluck" technique. RESULTS: A total of 14 upper tract urothelial carcinoma patients were analyzed, including 10 men and 4 women. The Hem-o-lok clip ligation took less than 20 s. In each patient, the clip was clearly visible and attached tightly to the ureter, and a clear distal ureter was observed in all patients. Histopathology results showed pT2 in 8 and pT3 in 6 patients. A median follow-up of 15 months revealed no extravesicular or intravesicular recurrences. CONCLUSIONS: Transurethral Hem-o-lok clip ligation technique provides a simple and safe option for distal ureter management in retroperitoneal laparoscopic RNU. This novel approach enables construction of a watertight system of the upper urinary tract, preventing the spread of tumor cells effectively and minimizing local tumor implantation risk.


Assuntos
Carcinoma de Células de Transição , Laparoscopia , Ureter , Neoplasias da Bexiga Urinária , Masculino , Humanos , Feminino , Ureter/cirurgia , Nefroureterectomia , Carcinoma de Células de Transição/cirurgia , Nefrectomia/métodos , Neoplasias da Bexiga Urinária/cirurgia , Ligadura , Laparoscopia/métodos , Instrumentos Cirúrgicos
17.
Sensors (Basel) ; 23(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36772513

RESUMO

The beam pattern of frequency diversity array (FDA) radar has a range-angle two-dimensional degree of freedom, which makes it possible to distinguish different targets from the same angle and brings a new approach to anti-jamming of radars. However, the beam pattern of conventional linearly frequency-biased FDA radar is range-angle-coupled and time-varying. The method of adding nonlinear frequency bias among the array elements of the FDA array has been shown to eliminate this coupling property while still allowing for better beam performance of the emitted beam. In this paper, we obtain a decoupled and time-invariant beam direction map using the FDA-multi-input-multi-output (FDA-MIMO) radar scheme and then obtain a sharp pencil-shaped main sphere beam pattern with range-angle dependence using a linear frequency offset scheme weighted by a Chebyshev window. Finally, the anti-interference performance of the proposed method is verified in an anti-interference experiment.

18.
Sensors (Basel) ; 23(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37571457

RESUMO

Wearable optical fiber sensors have great potential for development in medical monitoring. With the increasing demand for compactness, comfort, accuracy, and other features in new medical monitoring devices, the development of wearable optical fiber sensors is increasingly meeting these requirements. This paper reviews the latest evolution of wearable optical fiber sensors in the medical field. Three types of wearable optical fiber sensors are analyzed: wearable optical fiber sensors based on Fiber Bragg grating, wearable optical fiber sensors based on light intensity changes, and wearable optical fiber sensors based on Fabry-Perot interferometry. The innovation of wearable optical fiber sensors in respiration and joint monitoring is introduced in detail, and the main principles of three kinds of wearable optical fiber sensors are summarized. In addition, we discuss their advantages, limitations, directions to improve accuracy and the challenges they face. We also look forward to future development prospects, such as the combination of wireless networks which will change how medical services are provided. Wearable optical fiber sensors offer a viable technology for prospective continuous medical surveillance and will change future medical benefits.


Assuntos
Fibras Ópticas , Dispositivos Eletrônicos Vestíveis , Estudos Prospectivos , Luz , Interferometria
19.
Nano Lett ; 22(9): 3818-3824, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35471058

RESUMO

The rapidly growing demand of electrical vehicles (EVs) requires high-energy-density lithium-ion batteries (LIBs) with excellent cycling stability and safety performance. However, conventional polycrystalline high-Ni cathodes severely suffer from intrinsic chemomechanical degradation and fast capacity fade. The emerging single-crystallization strategy offers a promising pathway to improve the cathode's chemomechanical stability; however, the single-crystallinity of the cathode is not always guaranteed, and residual grain boundaries (GBs) could persist in nonideal synthesis conditions, leading to the formation of "quasi-single-crystalline" (QSC) cathodes. So far, there has been a lack of understanding of the influence of these residual GBs on the electrochemical performance and structural stability. Herein, we investigate the degradation pathway of a QSC high-Ni cathode through transmission electron microscopy and X-ray techniques. The residual GBs caused by insufficient calcination time dramatically exacerbate the cathode's chemomechanical instability and cycling performance. Our work offers important guidance for next-generation cathodes for long-life LIBs.

20.
Nano Lett ; 22(18): 7535-7544, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36070490

RESUMO

The rechargeability of aqueous zinc metal batteries is plagued by parasitic reactions of the zinc metal anode and detrimental morphologies such as dendritic or dead zinc. To improve the zinc metal reversibility, hereby we report a new solution structure of aqueous electrolyte with hydroxyl-ion scavengers and hydrophobicity localized in solvent clusters. We show that although hydrophobicity sounds counterintuitive for an aqueous system, hydrophilic pockets may be encapsulated inside a hydrophobic outer layer, and a hydrophobic anode-electrolyte interface can be generated through the addition of a cation-philic, strongly anion-phobic, and OH--reactive diluent. The localized hydrophobicity enables less active water and less absorbed water on the Zn anode surface, which suppresses the parasitic water reduction; while the hydroxyl-ion-scavenging functionality further minimizes undesired passivation layer formation, thus leading to superior reversibility (an average Zn plating/stripping efficiency of 99.72% for 1000 cycles) and lifetime (80.6% capacity retention after 5000 cycles) of zinc batteries.


Assuntos
Eletrólitos , Zinco , Ânions , Cátions , Interações Hidrofóbicas e Hidrofílicas , Solventes , Água
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