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1.
J Robot Surg ; 18(1): 264, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916783

RESUMEN

Upper hemi-sternotomy is a common approach for outflow graft anastomosis to the ascending aorta in minimally invasive left-ventricular assist device implantation. Right mini-thoracotomy may also be used, but use of robotic assistance has been reported only anecdotally. The aim of our study was to confirm the feasibility of robotically assisted suturing of the outflow graft anastomosis and to assess performance metrics for the robotic suturing part of the procedure. The procedure was carried out in eight cadaver studies by two surgeons. The assist device pump head was inserted through a left-sided mini-thoracotomy and the outflow graft was passed toward a right-sided second interspace mini-thoracotomy through the pericardium. After placement of a partial occlusion clamp on the ascending aorta, a longitudinal aortotomy was performed and the outflow graft to ascending aorta anastomosis was carried out robotically. The procedure was feasible in all eight attempts. The mean outflow graft anastomotic time was 20.1 (SD 6.8) min and the mean surgeon confidence and comfort levels to complete the anastomoses were 8.3 (SD 2.4) and 6.9 (SD2.2), respectively, on a ten-grade Likert scale. On open inspection of the anastomoses, there was good suture alignment in all cases. We conclude that suturing of a left-ventricular assist device outflow graft to the human ascending aorta is very feasible with good surgeon comfort. Anastomotic times are acceptable and suture placement can be performed with appropriate alignment.


Asunto(s)
Anastomosis Quirúrgica , Cadáver , Estudios de Factibilidad , Corazón Auxiliar , Procedimientos Quirúrgicos Mínimamente Invasivos , Tempo Operativo , Procedimientos Quirúrgicos Robotizados , Humanos , Procedimientos Quirúrgicos Robotizados/métodos , Procedimientos Quirúrgicos Robotizados/instrumentación , Anastomosis Quirúrgica/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Aorta/cirugía , Cirujanos , Técnicas de Sutura , Implantación de Prótesis/métodos , Toracotomía/métodos
2.
ChemSusChem ; : e202400626, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747027

RESUMEN

Dual-ion batteries (DIBs) represent a promising alternative for lithium ion batteries (LIBs) for various niche applications. DIBs with polymer-based active materials, here poly(2,2,6,6-tetramethylpiperidinyl-N-oxyl methacrylate) (PTMA), are of particular interest for high power applications, though they require appropriate electrolyte formulations. As the anion mobility plays a crucial role in transport kinetics, Li salts are varied using the well-dissociating solvent γ-butyrolactone (GBL). Lithium difluoro(oxalate)borate (LiDFOB) and lithium bis(oxalate)borate (LiBOB) improve cycle life in PTMA||Li metal cells compared to other Li salts and a LiPF6- and carbonate-based reference electrolyte, even at specific currents of 1.0 A g-1 (≈10C), whereas LiDFOB reveals a superior rate performance, i. e., ≈90 % capacity even at 5.0 A g-1 (≈50C). This is attributed to faster charge-transfer/mass transport, enhanced pseudo-capacitive contributions during the de-/insertion of the anions into the PTMA electrode and to lower overpotentials at the Li metal electrode.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38606845

RESUMEN

To address the issue that a single coating agent cannot simultaneously enhance Li+-ion transport and electronic conductivity of Ni-rich cathode materials with surface modification, in the present study, we first successfully synthesized a LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode material by a Taylor-flow reactor followed by surface coating with Li-BTJ and dispersion of vapor-grown carbon fibers treated with polydopamine (PDA-VGCF) filler in the composite slurry. The Li-BTJ hybrid oligomer coating can suppress side reactions and enhance ionic conductivity, and the PDA-VGCFs filler can increase electronic conductivity. As a result of the synergistic effect of the dual conducting agents, the cells based on the modified NCM811 electrodes deliver superior cycling stability and rate capability, as compared to the bare NCM811 electrode. The CR2032 coin-type cells with the NCM811@Li-BTJ + PDA-VGCF electrode retain a discharge specific capacity of ∼92.2% at 1C after 200 cycles between 2.8 and 4.3 V (vs Li/Li+), while bare NCM811 retains only 84.0%. Moreover, the NCM811@Li-BTJ + PDA-VGCF electrode-based cells reduced the total heat (Qt) by ca. 7.0% at 35 °C over the bare electrode. Remarkably, the Li-BTJ hybrid oligomer coating on the surface of the NCM811 active particles acts as an artificial cathode electrolyte interphase (ACEI) layer, mitigating irreversible surface phase transformation of the layered NCM811 cathode and facilitating Li+ ion transport. Meanwhile, the fiber-shaped PDA-VGCF filler significantly reduced microcrack propagation during cycling and promoted the electronic conductance of the NCM811-based electrode. Generally, enlightened with the current experimental findings, the concerted ion and electron conductive agents significantly enhanced the Ni-rich cathode-based cell performance, which is a promising strategy to apply to other Ni-rich cathode materials for lithium-ion batteries.

4.
ACS Appl Mater Interfaces ; 16(17): 21932-21942, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38649156

RESUMEN

Solid-state batteries based on lithium metal anodes, solid electrolytes, and composite cathodes constitute a promising battery concept for achieving high energy density. Charge carrier transport within the cells is governed by solid-solid contacts, emphasizing the importance of well-designed interfaces. A key parameter for enhancing the interfacial contacts among electrode active materials and electrolytes comprises externally applied pressure onto the cell stack, particularly in the case of ceramic electrolytes. Reports exploring the impact of external pressure on polymer-based cells are, however, scarce due to overall better wetting behavior. In this work, the consequences of externally applied pressure in view of key performance indicators, including cell longevity, rate capability, and limiting current density in single-layer pouch-type NMC622||Li cells, are evaluated employing cross-linked poly(ethylene oxide), xPEO, and cross-linked cyclodextrin grafted poly(caprolactone), xGCD-PCL. Notably, externally applied pressure substantially changes the cell's electrochemical cycling performance, strongly depending on the mechanical properties of the considered polymers. Higher external pressure potentially enhances electrode-electrolyte interfaces, thereby boosting the rate capability of pouch-type cells, despite the fact that the cell longevity may be reduced upon plastic deformation of the polymer electrolytes when passing beyond intrinsic thresholds of compressive stress. For the softer xGCD-PCL membrane, cycling of cells is only feasible in the absence of external pressure, whereas in the case of xPEO, a trade-off between enhanced rate capability and minimal membrane deformation is achieved at cell pressures of ≤0.43 MPa, which is considerably lower and more practical compared to cells employing ceramic electrolytes with ≥5 MPa external pressure.

5.
Phys Chem Chem Phys ; 26(4): 3516-3524, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38206350

RESUMEN

Herein, a mesoporous MnCo2O4/Co3O4 nanocomposite was fabricated using a polyvinylpyrrolidone (PVP)-assisted hydrothermal synthesis method by maintaining only the non-stoichiometric ratio of Mn and Co (2 : 6), leading to an extra phase of Co3O4 coupled with MnCo2O4. Microstructural analysis showed that the obtained sample has a uniform nanowire-like morphology composed of interconnected nanoparticles. The stoichiometric ratio (2 : 4) was maintained to synthesize pure MnCo2O4 for comparative analysis. However, the obtained structure of pure MnCo2O4 was found to be irregular and fragile. After their employment as anode-active materials, the nanocomposite electrode showed superior high rate capability (1043.8 mA h g-1 at 5C) and long-term cycling stability (773.6 mA h g-1 after 500 cycles at 0.5C) in comparison to the pure MnCo2O4 electrode (771.5 mA h g-1 at 5C and 638.9 mA h g-1 at 0.5C after 500 cycles). It was believed that the extra phase of Co3O4 may also participate in the electrochemical reactions due to its high electrochemically active nature. Benefiting from the appealing architectural features and striking synergistic effect, the integrated MnCo2O4/Co3O4 nanocomposite anode exhibits excellent electrochemical properties and high cycle stability for LIBs.

6.
Clin Cardiol ; 47(2): e24197, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38069663

RESUMEN

BACKGROUND: Postinterventional sonographic assessment of the femoral artery after transfemoral transcatheter aortic valve replacement (TF-TAVR) has the potential to identify several pathologies. We investigated the incidence and risk factors of femoral vessel complications in a modern TAVR collective using postinterventional sonography. METHODS: Between September 2017 and March 2022, 480 patients underwent TF-TAVR with postinterventional femoral sonography at a single center. Clinical outcomes and adverse events were analyzed after the Valve Academic Research Consortium 3 (VARC-3) criteria. RESULTS: In this cohort (51.2% male; age 80 ± 7.5 years, median EuroSCORE II 3.7) 74.8% (n = 359) were implanted with a self-expandable and 25.2% (n = 121) with a balloon-expandable valve. The main access (valve-delivery) was located right in 91.4% (n = 438), and the primary closure system was Proglide in 95% (n = 456). Vascular complications (VC) were observed in 29.16% (n = 140) of patients; 23.3% (n = 112) presented with minor- and 5.8% (n = 28) with major VC. Postinterventional femoral artery stenosis on the main access was observed in 9.8% (n = 47). Multivariable logistic regression analysis revealed female sex (p = .03, odds ratio [OR] 2.32, 95% confidence interval [CI] 1.09-4.89) and the number of used endovascular closure devices (p = .014, OR 0.11, 95%CI 0.02-0.64) as predictive factors for femoral artery stenosis. CONCLUSIONS: The incidence of postinterventional femoral artery stenosis following TF-TAVR was higher than expected with a number of used closure devices and female sex being independent risk factors. Considering the continuous advance of TAVR in low-risk patients with preserved physical activity, emphasis should be directed at the correct diagnosis and follow-up of these complications.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Enfermedades Vasculares , Humanos , Masculino , Femenino , Anciano , Anciano de 80 o más Años , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Prótesis Valvulares Cardíacas/efectos adversos , Constricción Patológica/complicaciones , Constricción Patológica/cirugía , Resultado del Tratamiento , Factores de Riesgo , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/cirugía , Estenosis de la Válvula Aórtica/diagnóstico , Estudios Retrospectivos
7.
Adv Sci (Weinh) ; 11(1): e2305282, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37939283

RESUMEN

Full exhaustion in specific energy/energy density of state-of-the-art LiNix Coy Mnz O2 (NCM)-based Li-ion batteries (LIB) is currently limited for reasons of NCM stability by upper cut-off voltages (UCV) below 4.3 V. At higher UCV, structural decomposition triggers electrode crosstalk in the course of enhanced transition metal dissolution and leads to severe specific capacity/energy fade; in the worst case to a sudden death phenomenon (roll-over failure). The additive lithium difluorophosphate (LiDFP) is known to suppress this by scavenging dissolved metals, but at the cost of enhanced toxicity due to the formation of organofluorophosphates (OFPs). Addition of film-forming electrolyte additives like vinylene carbonate (VC) can intrinsically decrease OFP formation in thermally aged LiDFP-containing electrolytes, though the benefit of this dual-additive approach can be questioned at higher UCVs. In this work, VC is shown to decrease the formation of potentially toxic OFPs within the electrolyte during cycling at conventional UCVs but triggers OFP formation at higher UCVs. The electrolyte contains soluble VC-polymerization products. These products are formed at the cathode during VC oxidation (and are found within the cathode electrolyte interphase (CEI), suggesting an OFP electrode crosstalk of VC decomposition species, as the OFP-precursor molecules are shown to be formed at the anode.

8.
Small ; 20(6): e2305203, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37797185

RESUMEN

Continuous lithium (Li) depletion shadows the increase in energy density and safety properties promised by zero-excess lithium metal batteries (ZELMBs). Guiding the Li deposits toward more homogeneous and denser lithium morphology results in improved electrochemical performance. Herein, a lithium nitrate (LiNO3 ) enriched separator that improves the morphology of the Li deposits and facilitates the formation of an inorganic-rich solid-electrolyte interphase (SEI) resulting in an extended cycle life in Li||Li-cells as well as an increase of the Coulombic efficiency in Cu||Li-cells is reported. Using a LiNi0.6 Co0.2 Mn0.2 O2 positive electrode in NCM622||Cu-cells, a carbonate-based electrolyte, and a LiNO3 enriched separator, an extension of the cycle life by more than 50 cycles with a moderate capacity fading compared to the unmodified separator is obtained. The relative constant level of LiNO3 in the electrolyte, maintained by the LiNO3 enriched separator throughout the cycling process stems at the origin of the improved performance. Ion chromatography measurements carried out at different cycles support the proposed mechanism of a slow and constant release of LiNO3 from the separator. The results indicate that the strategy of using a LiNO3 enriched separator instead of LiNO3 as a sacrificial electrolyte additive can improve the performance of ZELMBs further by maintaining a compact and thus stable SEI layer on Li deposits.

9.
ACS Appl Mater Interfaces ; 15(46): 53526-53532, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37936378

RESUMEN

The film-forming electrolyte additive/co-solvent fluoroethylene carbonate (FEC) can play a crucial role in enabling high-energy-density lithium metal batteries (LMBs). Its beneficial impact on homogeneous and compact lithium (Li) deposition morphology leads to improved Coulombic efficiency (CE) of the resulting cell chemistry during galvanostatic cycling and consequently an extended cell lifetime. Herein, the impact of this promising additive/co-solvent on selected properties of LMBs is systematically investigated by utilizing an in-house developed lithium pretreatment method. The results reveal that as long as FEC is present in the organic carbonate-based electrolyte, a dense mosaic-like lithium morphology of Li deposits with a reduced polarization of only 20 mV combined with a prolonged cycle life is achieved. When the pretreated Li electrodes with an FEC-derived preformed SEI (pSEI) are galvanostatically cycled with the FEC-free electrolyte, the described benefits induced by the additive are not observable. These results underline that the favorable properties of the FEC-derived SEI are beneficial only if there is unreacted FEC in the electrolyte formulation left to constantly reform the interphase layer, which is especially important for anodes with high-volume changes and dynamic surfaces like lithium metal and lithiated silicon.

10.
Phys Chem Chem Phys ; 25(36): 24278-24286, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37681262

RESUMEN

The state-of-charge (SOC) is an essential parameter for battery management systems to reflect and monitor the remaining capacity of individual battery cells. In addition to its application at the cell level, the SOC also plays an important role in the investigation of redox processes of cathode active materials (CAMs) in lithium ion batteries (LIBs) during electrochemical cycling. These processes can be influenced by a large variety of factors such as active material properties, inhomogeneities of the electrode, degradation phenomena and the charge/discharge protocol during cycling. Consequently, non-uniform redox reactions can occur, resulting in charge heterogeneities of the active material. This heterogeneity can translate into accelerated aging of the CAM and a reduction in reversible capacity of the battery cell, since the active material is not fully utilized. To understand and monitor the SOC heterogeneity at the mesoscale, a wide range of techniques have been implemented in the past. In this perspective an overview of current state-of-the-art techniques to evaluate charge heterogeneities of CAMs in LIBs is presented. Therefore, techniques which utilize synchrotron radiation like X-ray absorption near-edge structure (XANES) and transmission X-ray spectroscopy (TXM) are presented as well as Raman spectroscopy and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Next to these established techniques, classification single particle inductively coupled plasma optical emission spectroscopy (CL-SP-ICP-OES) as a new approach is also discussed in this perspective. For these techniques, the areas of application, advantages as well as drawbacks are highlighted and discussed.

11.
iScience ; 26(9): 107517, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37636078

RESUMEN

Laser desorption/ionization-mass spectrometry (LDI-MS) is introduced as a complementary technique for the analysis of interphases formed at electrode|electrolyte interfaces in lithium ion batteries (LIBs). An understanding of these interphases is crucial for designing interphase-forming electrolyte formulations and increasing battery lifetime. Especially organic species are analyzed more effectively using LDI-MS than with established methodologies. The combination with trapped ion mobility spectrometry and tandem mass spectrometry yields additional structural information of interphase components. Furthermore, LDI-MS imaging reveals the lateral distribution of compounds on the electrode surface. Using the introduced methods, a deeper understanding of the mechanism of action of the established solid electrolyte interphase-forming electrolyte additive 3,4-dimethyloxazolidine-2,5-dione (Ala-N-CA) for silicon/graphite anodes is obtained, and active electrochemical transformation products are unambiguously identified. In the future, LDI-MS will help to provide a deeper understanding of interfacial processes in LIBs by using it in a multimodal approach with other surface analysis methods to obtain complementary information.

12.
ChemSusChem ; 16(21): e202300445, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37606900

RESUMEN

Dual-ion batteries (DIBs) are attracting attention due to their high operating voltage and promise in stationary energy storage applications. Among various anode materials, elements that alloy and dealloy with lithium are assumed to be prospective in bringing higher capacities and increasing the energy density of DIBs. In this work, antimony in the form of a composite with carbon (Sb-C) is evaluated as an anode material for DIB full cells for the first time. The behaviour of graphite||Sb-C cells is assessed in highly concentrated electrolytes in the absence and presence of an electrolyte additive (1 % vinylene carbonate) and in two cell voltage windows (2-4.5 V and 2-4.8 V). Sb-C full cells possess maximum estimated specific energies of 290 Wh/kg (based on electrode masses) and 154 Wh/kg (based on the combined mass of electrodes and active salt). The work expands the knowledge on the operation of DIBs with non-graphitic anodes.

13.
Sci Rep ; 13(1): 10934, 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37414786

RESUMEN

Organic radical batteries (ORBs) represent a viable pathway to a more sustainable energy storage technology compared to conventional Li-ion batteries. For further materials and cell development towards competitive energy and power densities, a deeper understanding of electron transport and conductivity in organic radical polymer cathodes is required. Such electron transport is characterised by electron hopping processes, which depend on the presence of closely spaced hopping sites. Using a combination of electrochemical, electron paramagnetic resonance (EPR) spectroscopic, and theoretical molecular dynamics as well as density functional theory modelling techniques, we explored how compositional characteristics of cross-linked poly(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl methacrylate) (PTMA) polymers govern electron hopping and rationalise their impact on ORB performance. Electrochemistry and EPR spectroscopy not only show a correlation between capacity and the total number of radicals in an ORB using a PTMA cathode, but also indicates that the state-of-health degrades about twice as fast if the amount of radical is reduced by 15%. The presence of up to 3% free monomer radicals did not improve fast charging capabilities. Pulsed EPR indicated that these radicals readily dissolve into the electrolyte but a direct effect on battery degradation could not be shown. However, a qualitative impact cannot be excluded either. The work further illustrates that nitroxide units have a high affinity to the carbon black conductive additive, indicating the possibility of its participation in electron hopping. At the same time, the polymers attempt to adopt a compact conformation to increase radical-radical contact. Hence, a kinetic competition exists, which might gradually be altered towards a thermodynamically more stable configuration by repeated cycling, yet further investigations are required for its characterisation.


Asunto(s)
Electrólitos , Polímeros , Transporte de Electrón , Electrólitos/química , Radicales Libres/química , Polímeros/química , Electrónica
14.
Small ; 19(44): e2302486, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37403278

RESUMEN

Effective electrolyte compositions are of primary importance in raising the performance of lithium-ion batteries (LIBs). Recently, fluorinated cyclic phosphazenes in combination with fluoroethylene carbonate (FEC) have been introduced as promising electrolyte additives, which can decompose to form an effective dense, uniform, and thin protective layer on the surface of electrodes. Although the basic electrochemical aspects of cyclic fluorinated phosphazenes combined with FEC were introduced, it is still unclear how these two compounds interact constructively during operation. This study investigates the complementary effect of FEC and ethoxy(pentafluoro)cyclotriphosphazene (EtPFPN) in aprotic organic electrolyte in LiNi0.5 Co0.2 Mn0.3 O ∥ SiOx /C full cells. The formation mechanism of lithium ethyl methyl carbonate (LEMC)-EtPFPN interphasial intermediate products and the reaction mechanism of lithium alkoxide with EtPFPN are proposed and supported by Density Functional Theory calculations. A novel property of FEC is also discussed here, called molecular-cling-effect (MCE). To the best knowledge, the MCE has not been reported in the literature, although FEC belongs to one of the most investigated electrolyte additives. The beneficial MCE of FEC toward the sub-sufficient solid-electrolyte interphase forming additive compound EtPFPN is investigated via gas chromatography-mass spectrometry, gas chromatography high resolution-accurate mass spectrometry, in situ shell-isolated nanoparticle-enhanced Raman spectroscopy, and scanning electron microscopy.

15.
RSC Adv ; 13(26): 17947-17958, 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37323458

RESUMEN

A processing solvent-free manufacturing process for cross-linked ternary solid polymer electrolytes (TSPEs) is presented. Ternary electrolytes (PEODA, Pyr14TFSI, LiTFSI) with high ionic conductivities of >1 mS cm-1 are obtained. It is shown that an increased LiTFSI content in the formulation (10 wt% to 30 wt%) decreases the risk of short-circuits by HSAL significantly. The practical areal capacity increases by more than a factor of 20 from 0.42 mA h cm-2 to 8.80 mA h cm-2 before a short-circuit occurs. With increasing Pyr14TFSI content, the temperature dependency of the ionic conductivity changes from Vogel-Fulcher-Tammann to Arrhenius behavior, leading to activation energies for the ion conduction of 0.23 eV. In addition, high Coulombic efficiencies of 93% in Cu‖Li cells and limiting current densities of 0.46 mA cm-2 in Li‖Li cells were obtained. Due to a temperature stability of >300 °C the electrolyte guarantees high safety in a broad window of conditions. In LFP‖Li cells, a high discharge capacity of 150 mA h g-1 after 100 cycles at 60 °C was achieved.

16.
Polymers (Basel) ; 15(9)2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-37177276

RESUMEN

Poly(ethylene oxide) block copolymers (PEOz BCP) have been demonstrated to exhibit remarkably high lithium ion (Li+) conductivity for Li+ batteries applications. For linear poly(isoprene)-b-poly(styrene)-b-poly(ethylene oxide) triblock copolymers (PIxPSyPEOz), a pronounced maximum ion conductivity was reported for short PEOz molecular weights around 2 kg mol-1. To later enable a systematic exploration of the influence of the PIx and PSy block lengths and related morphologies on the ion conductivity, a synthetic method is needed where the short PEOz block length can be kept constant, while the PIx and PSy block lengths could be systematically and independently varied. Here, we introduce a glycidyl ether route that allows covalent attachment of pre-synthesized glycidyl-end functionalized PEOz chains to terminate PIxPSy BCPs. The attachment proceeds to full conversion in a simplified and reproducible one-pot polymerization such that PIxPSyPEOz with narrow chain length distribution and a fixed PEOz block length of z = 1.9 kg mol-1 and a D = 1.03 are obtained. The successful quantitative end group modification of the PEOz block was verified by nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). We demonstrate further that with a controlled casting process, ordered microphases with macroscopic long-range directional order can be fabricated, as demonstrated by small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It has already been shown in a patent, published by us, that BCPs from the synthesis method presented here exhibit comparable or even higher ionic conductivities than those previously published. Therefore, this PEOz BCP system is ideally suitable to relate BCP morphology, order and orientation to macroscopic Li+ conductivity in Li+ batteries.

17.
Sensors (Basel) ; 23(9)2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37177495

RESUMEN

In sub-surface drilling rigs, one key critical crisis is unwanted influx into the borehole as a result of increasing the influx rate while drilling deeper into a high-pressure gas formation. Although established risk assessments in drilling rigs provide a high degree of protection, uncertainty arises due to the behavior of the formation being drilled into, which may cause crucial situations at the rig. To overcome such uncertainties, real-time sensor measurements are used to predict, and thus prevent, such crises. In addition, new understandings of the effective events were derived from raw data. In order to avoid the computational overhead of input feature analysis that hinders time-critical prediction, EventTracker sensitivity analysis, an incremental method that can support dimensionality reduction, was applied to real-world data from 1600 features per each of the 4 wells as input and 6 time series per each of the 4 wells as output. The resulting significant input series were then introduced to two classification methods: Random Forest Classifier and Neural Networks. Performance of the EventTracker method was understood correlated with a conventional manual method that incorporated expert knowledge. More importantly, the outcome of a Neural Network Classifier was improved by reducing the number of inputs according to the results of the EventTracker feature selection. Most important of all, the generation of results of the EventTracker method took fractions of milliseconds that left plenty of time before the next bunch of data samples.

18.
SLAS Discov ; 28(5): 240-246, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37031752

RESUMEN

Acoustic droplet ejection-open port interface-mass spectrometry (ADE-OPI-MS) is a novel label-free analytical technique, promising to become a versatile readout for high-throughput screening (HTS) applications. The recent introduction of ADE-OPI-MS devices to the laboratory equipment market, paired with their compatibility with laboratory automation platforms, should facilitate the adoption of this technology by a broader community. Towards this goal, instrument robustness in the context of HTS campaigns - where up to millions of samples in complex matrices are tested in a short time frame - represents a major challenge, which explains the absence of detailed literature reports on this subject. Here, we present the results of our first fully automated HTS campaign, based on the ADE-OPI-MS technology, aiming to identify inhibitors of a metabolic enzyme in a >1 million compound library. The report encompasses the assay development and validation steps, as well as the adaptation for HTS requirements, where refinement of the capillary cleaning concept was crucial for final success. Altogether, our study unequivocally demonstrates the applicability of the ADE-OPI-MS technology for HTS-based drug discovery.


Asunto(s)
Descubrimiento de Drogas , Ensayos Analíticos de Alto Rendimiento , Ensayos Analíticos de Alto Rendimiento/métodos , Espectrometría de Masas , Descubrimiento de Drogas/métodos , Acústica , Automatización de Laboratorios
19.
ChemSusChem ; 16(9): e202300451, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37104827

RESUMEN

Invited for this month's cover is the group of Martin Winter at the University of Münster. The image shows idea of the developed sample treatment method enabling the accumulation of solid electrolyte interphase originating compounds. The Research Article itself is available at 10.1002/cssc.202201912.

20.
Anal Methods ; 15(16): 2030-2038, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37060114

RESUMEN

Over the last years, inductively coupled plasma mass spectrometry (ICP-MS) has been applied as a method for human-biomonitoring of metals in the concentration range of occupational and environmental medicine. In large scale routine monitoring, the determination of mercury (Hg) by ICP-MS remains challenging due to several reasons. Amongst others, stability of dissolved Hg and avoiding memory effects are the key facts for reliable quantification. To address these issues, we developed a robust approach for biomonitoring of mercury in human urine samples by ICP-MS. Using a solution containing HNO3, HCl and thiourea, prepared samples and calibrators were stabilized for up to 72 h. A rinse time of only 30 seconds efficiently prevented contamination of consecutive samples with Hg concentrations up to 30 µg L-1, hence significantly reducing acquisition times compared to published methods. Recovery experiments revealed iridium as an ideal internal standard to compensate matrix effects independently from creatinine concentration. Recoveries of 95.0-104.0% were obtained for Hg levels covering the range of biomonitoring guidance values established by the German Human-Biomonitoring Commission. Excellent intra-day precision and inter-day precision of ≤3.0% for two different Hg levels were achieved. The detection and quantification limit accounted for 21.7 ng L-1 and 65.6 ng L-1, respectively, enabling reliable quantification even in the range of environmental background exposures. Additionally, the method was externally validated by successful participation in the inter-laboratory comparison program G-EQUAS. With the developed method, we hence provide a sensitive and robust tool for mercury exposure assessments in future large scale human-biomonitoring studies.


Asunto(s)
Mercurio , Humanos , Mercurio/orina , Tiourea , Monitoreo Biológico , Espectrofotometría Atómica/métodos , Espectrometría de Masas/métodos
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