Intensity Decay Research Articles

Impenetrable Barrier at the Metal-Mott Insulator Junction in Polymorphic 1H and 1T NbSe2 Lateral Heterostructure.

When a metal makes contact with a band insulator, charge transfer occurs across the interface leading to band bending and a Schottky barrier with rectifying behavior. The nature of metal-Mott insulator junctions, however, is still debated due to challenges in experimental probes of such vertical heterojunctions with buried interfaces. Here, we grow lateral polymorphic heterostructures of single-layer metallic 1H and Mott insulating 1T NbSe2 by molecular beam epitaxy. We find a one-dimensional metallic channel along the interface due to the appearance of quasiparticle states with an intensity decay following 1/x2, indicating an impenetrable barrier. Near the interface, the Mott gap exhibits a strong spatial dependence arising from the difference in lattice constants between the two phases, consistent with our density functional theory calculations. These results provide clear experimental evidence for an impenetrable barrier at the metal-Mott insulator junction and the high tunability of a Mott insulator by strain.

Luminescence and microstructural characteristics of Eu2O3-doped SrAl2O4 single crystals

Single crystals of SrAl2O4 prepared with 0.2–2.0 mol% Eu2O3 were synthesized using the optical floating zone method using ceramic rods that had been prepared under reducing conditions to favor conversion of Eu3+ to Eu2+. Samples were then characterized by a combination of X-ray diffraction (XRD), X-ray photoelectron (XPS), positron annihilation, electron paramagnetic resonance (EPR), photoluminescence excitation (PLE) and photoluminescence (PL) spectroscopic techniques, and their excited state lifetimes were measured. XRD showed that the crystal samples were all in the monoclinic phase. EPR and PL techniques indicated that they contained Eu2+, although XPS indicated that the Eu3+ reduction was only ∼50%. Positron annihilation spectroscopy demonstrated that all of the samples contained a considerable number of defects that act as positron traps, and were influenced by the amount of Eu2O3 used in the crystal synthesis. These defects did not show an EPR signal, which suggests that they may correspond structural vacancies, possibly due to the presence of cation vacancies as a result of incorporation of some Eu3+ in the divalent cation sites. However, EPR did reveal a small amount of anionic paramagnetic defects, and showed a progressive broadening of the Eu2+ resonance for crystals synthesized with Eu2O3 concentrations >0.5 mol%. The intensity of the PLE spectra increased with Eu2O3 concentration, and the relative proportions of the peaks at 3.62 eV (360 nm) and 3.13 eV (417 nm) changed with Eu2O3 concentration. The PL spectra showed a broad green emission peak at 2.52 eV (518 nm), which is attributed to 4f65d-4f7 charge transfer transitions in Eu2+. Both its intensity and fluorescence decay time increased with Eu2O3 concentration, reached a maximum with the sample prepared with 1.5 mol% Eu2O3, then decreased with higher Eu2O3 concentrations.

Vacuum-Vapor-Deposited 0D/3D All-Inorganic Perovskite Composite Films toward Low-Threshold Amplified Spontaneous Emission and Lasing.

Vacuum vapor deposition (VVD) is a promising way to advancing the commercialization of perovskite light sources owing to its convenience for wafer-scale mass production and compatibility with silicon photonics manufacturing infrastructure. However, the light emission performance of VVD-grown perovskites still lags far behind that of the conventional solution-processed counterparts due to their inferior luminescence properties. Here, a 0D/3D cesium-lead-bromide perovskite composite film is prepared on Si/SiO2 substrates through composition modulation with the VVD method, which exhibits an ultralow amplified spontaneous emission (ASE) threshold down to 14.3 µJ cm-2 in the optimal films, which is on par with that of the solution-processed counterparts. Meanwhile, they also display intriguing operational stability with negligible emission intensity decay under continuous excitation above ASE threshold for 4h in the air. The outstanding ASE performance mainly originates from the reduced trap density and weakened electron-phonon coupling in the 3D CsPbBr3 phase enabled by the incorporation of the 0D Cs4 PbBr6 phase. Finally, by integrating the composite film with the distributed feedback (DFB) cavity, DFB lasing is achieved with a low threshold of 18.2 µJ cm-2 under nanosecond-pulsed laser pumping, which highlights the potential of VVD-processed perovskites for developing high-performance lasers.

Ultra-short T2 components imaging of the whole brain using 3D dual-echo UTE MRI with rosette k-space pattern.

This study aimed to develop a new 3D dual-echo rosette k-space trajectory, specifically designed for UTE MRI applications. The imaging of the ultra-short transverse relaxation time (uT2 ) of brain was acquired to test the performance of the proposed UTE sequence. The rosette trajectory was developed based on rotations of a "petal-like" pattern in the kx -ky plane, with oscillated extensions in the kz -direction for 3D coverage. Five healthy volunteers underwent 10 dual-echo 3D rosette UTE scans with various TEs. Dual-exponential complex model fitting was performed on the magnitude data to separate uT2 signals, with the output of uT2 fraction, uT2 value, and long-T2 value. The 3D rosette dual-echo UTE sequence showed better performance than a 3D radial UTE acquisition. More significant signal intensity decay in white matter than gray matter was observed along with the TEs. The white matter regions had higher uT2 fraction values than gray matter (10.9% ± 1.9% vs. 5.7% ± 2.4%). The uT2 value was approximately 0.10ms in white matter . The higher uT2 fraction value in white matter compared to gray matter demonstrated the ability of the proposed sequence to capture rapidly decaying signals.

A hybrid stochastic Lagrangian – cellular automata framework for modelling fire propagation in inhomogeneous terrains

A stochastic model motivated by the Lagrangian transported probability density function method for turbulent reacting flows and the cellular automata approach for forest fires was put together to simulate propagation of fires in terrains with inhomogeneous composition. In contrast to the usual cellular automata models for fires where the probability of ignition is prescribed, here the ignition of cells is determined by a random walk that mimics turbulent convection and diffusion of the hot gases and firebrands from upwind and neighbouring fire fronts. Radiation is also included. The model is aimed at speed of computation while approximating the key physics through only a few terrain-related inputs and tunable parameters representing fire intensity, hot gas and ember decay timescales, cell ignition delay and local turbulence. These parameters were calibrated against controlled fire experiments and the model was then used to give reasonable predictions for fires of increasing complexity. The presented framework allows improvements for more accurate representation of the flammable material characteristics, fire-induced flow modifications, and most other phenomena present in fires, hence providing an extendable and simple yet physically-realistic novel modelling approach.

Multi‐Scale Kelvin‐Helmholtz Instability Dynamics Observed by PMC Turbo on 12 July 2018: 2. DNS Modeling of KHI Dynamics and PMC Responses

AbstractKjellstrand et al. (2022), https://10.1029/2021JD036232 describes the evolution and dynamics of a strong, large‐scale Kelvin‐Helmholtz instability (KHI) event observed in polar mesospheric clouds (PMCs) on 12 July 2018 by high‐resolution imagers aboard the PMC Turbulence (PMC Turbo) stratospheric long‐duration balloon experiment. The imaging provides evidence of KH billow interactions and instabilities that are strongly influenced by gravity waves at larger scales. Specific features include initially separated regions of KHI, secondary convective and KH instabilities of individual billows, and “tubes” and “knots” that arise where billow cores are mis‐aligned or discontinuous along their axes. This study describes a direct numerical simulation of KH billow interactions in a periodic domain seeded with random initial noise that enables excitation of multiple KH billows exhibiting variable phase structures that capture multiple features of the observed KHI dynamics. Variable KH billow phases along their axes yield initial vortex tubes having diagonal alignments that link adjacent, but mis‐aligned, billow cores. Weak initial vortex tubes and billow cores having nearly orthogonal alignments amplify, interact strongly, and drive intense vortex knots at these sites. These vortex tube and knot (T&K) dynamics excite “twist waves” that unravel the initial vortex tubes, and drive increasingly strong vortex interactions and a cascade of energy and enstrophy to successively smaller scales in the turbulence inertial range. The implications of T&K dynamics are much more rapid and intense breakdown and decay of the KH billows, and significantly enhanced energy dissipation rates, where these interactions occur.

Non-destructive evaluation of ammonium oxalate treatment penetration depth using micro-SORS

The determination of the penetration depth of treatments is a crucial issue in conservation science for assessing treatments efficacy. Micro-spatially offset Raman spectroscopy (micro-SORS), that permits the non-destructive collection of Raman photons generated under the surface of a turbid material, here has been used to non-destructively retrieve the distribution of oxalates formed after ammonium oxalate (AmOX) treatment on plasters. Two sets of samples treated with AmOX have been studied, namely plaster mock-ups and plaster fragments collected from the painted façades of Palazzo Besta in Teglio (Sondrio, Italy). The evaluation of the distribution of the newly formed oxalates was carried out considering the slope of the oxalates/calcite Raman bands intensity decay trend with increasing micro-SORS defocusing distance. Micro-SORS outcomes were found to be consistent with those obtained with conventional micro-Raman performed on cross-section, confirming the extension of this innovative method to the evaluation of treatments efficacy.

Microscopy Visualization of Carrier Transport in CdSeTe/CdTe Solar Cells

Solar cells are essentially minority carrier devices, and it is therefore of central importance to understand the pertinent carrier transport processes. Here, we advanced a transport imaging technique to directly visualize the charge motion and collection in the direction of relevant carrier transport and to understand the cell operation and degradation in state-of-the-art cadmium telluride solar cells. We revealed complex carrier transport profiles in the inhomogeneous polycrystalline thin-film solar cell, with the influence of electric junction, interface, recombination, and material composition. The pristine cell showed a unique dual peak in the carrier transport light intensity decay profile, and the dual peak feature disappeared on a degraded cell after light and heat stressing in the lab. The experiments, together with device modeling, suggested that selenium diffusion plays an important role in carrier transport. The work opens a new forum by which to understand the carrier transport and bridge the gap between atomic/nanometer-scale chemical/structural and submicrometer optoelectronic knowledge.

A wide solar spectrum utilization and fast charge carrier transport upon variable GaAs interlayer thickness in ZnPc/GaAs/ZnPc hybrid thin-film structures

The effects of inorganic layer thickness on the photophysical properties of the organic layer in an organic-inorganic hybrid system were investigated in this paper. Photosensitive Zinc Phthalocyanine (ZnPc) and GaAs layers were alternatively stacked through simple physical vapor deposition, and the impact of GaAs layer thickness was explored through structural, optical, and electrical characterization techniques. The strain-induced quantum size effect was evident in the hybrid structure, and it was confirmed in Raman analysis with broad vibration peaks of the GaAs phase, which resulted in a decrease in the GaAs thickness < Bohr radius (RB). In addition, a complementary absorption edge was obtained at 295 nm along with ZnPc absorption features, but GaAs failed to contribute to spectral absorption with its thickness > RB. The decreased photoluminescence intensity and fluorescence decay time of ZnPc after incorporation of GaAs imply that charge transfer from ZnPc to GaAs occurs quickly. The transient photocurrent measurement demonstrates that the current density of hybrid film with GaAs thickness < Bohr radius was significantly increased. As expected, the GaAs with thickness above the Bohr radius is ineffective for improving the photocurrent. Impedance spectroscopy analysis was applied to explore the electrical transport behavior in the hybrid system using a two-electrode system. An ultra-thin GaAs layer noticeably promoted mass transfer at the ZnPc-GaAs interface and increased the conductivity of the hybrid system with the least charge transfer resistance.

Influence of Rotation Speed on Flow Field and Hydraulic Noise in the Conduit of a Vertical Axial-Flow Pump under Low Flow Rate Condition

The complex flow inside the axial-flow pump device will cause the problem of hydraulic noise; in order to explore the influence of the law of rotation speed on the internal flow characteristics and hydraulic noise of the axial-flow pump conduit, a combination of Computational Fluid Dynamics (CFD) and Computational Acoustics (CA) was used to numerically solve the flow field and internal sound field in the pump device. The results showed that the flow in the elbow inlet conduit was smooth at different rotation speeds, and there was no obvious unstable flow. The higher the rotation speed, the more disordered the flow pattern in the left half of the elbow, which intensifies the unstable flow in the straight outlet conduit. The impeller is the main sound source of the internal hydrodynamic noise of the vertical axial-flow pump device. When the sound source propagates upstream and downstream along the conduit, the Total Sound Source Intensity (TSSI) gradually decays with the increase of distance; the greater the rotation speed is, the faster the Total Sound Source Intensity (TSSI) decays. When the rotation speed was increased from 1450 r/min to 2200 r/min, the TSSI in the straight outlet conduit was attenuated by 8.9 dB, 13.9 dB, and 16.0 dB respectively, and the TSSI in the elbow inlet conduit was attenuated by 11.0 dB, 13.5 dB, and 25.9 dB respectively. The vortex structure in the conduit induces flow noise and delays the attenuation of TSSI in the propagation process; with the increase of rotation speed, this delay will be more obvious.

Heavily cerium-doped (Gd,La)AlO3 ceramic scintillators: Material optimization study

Cerium-doped aluminates with a perovskite structure are studied for their prospective material properties aiming at their application in scintillation detectors. These materials exhibit high density, and thermal and chemical stability and thanks to the allowed 5d-4f transition of Ce3+ also high scintillation emission intensity and fast decay can be obtained. Commercially successful perovskite scintillator is the cerium-doped yttrium aluminium perovskite (YAlO3:Ce) produced in single crystal form by the Czochralski method. To overcome its disadvantage of low density and effective atomic number the single crystal of gadolinium aluminium perovskite doped with cerium (GdAlO3:Ce) was studied, but has shown significantly lower light. This work pursues a new approach to improve the scintillation properties of this material. Ceramic pellets of gadolinium aluminium perovskite doped with cerium and admixed with lanthanum ((Gd,La)AlO3:Ce) were prepared using co-precipitation method. The effect of cerium and lanthanum content was studied using the radioluminescence and luminescence spectroscopy. An improvement of scintillation properties (emission intensity and decay kinetics), in comparison to GdAlO3:Ce reported so far, was achieved.

Thermal stability and closure temperature of barite for electron spin resonance dating

Electron spin resonance (ESR) dating has been applied to barite from hydrothermal vents. Barite in hydrothermal vents cools down rapidly after formation so little attention was paid to the thermal stability of the ESR signal of barite for dating. To discern multiple episodes of fluid flow or to date barite in other geological settings, it is essential to know how the ESR intensity decays with heat, the characteristic decay time and the closure temperature. In this study, we demonstrate that the decay of the ESR intensity of the SO 3 − radical in barite is a second-order reaction. The characteristic decay time for the ESR intensity to drop by half at 100 °C, 200 °C, 300 °C and 500 °C is of the order of magnitude of 10 6 years, 10 years, 10 h and 1 s respectively. The closure temperature of barite is generally between 190 and 340 °C. These results provide essential information on environments where the ESR intensity in barite is stable and conditions under which ESR ages can be erased. • ESR intensity of barite decreases rapidly between 300 and 400 °C. • The thermal decay of ESR intensity in barite is a second-order reaction. • The characteristic decay time is at least 8 Ma at 100 °C and 14 years at 200 °C. • The closure temperature is generally between 190 and 340 °C. • ESR dating of barite can be applied to a variety of geological settings.

Effects of moisture content on the enolization products formation in glucose-proline Maillard reaction models.

2,3-Dihydro-3,5-dihydroxy-6-methyl-4(H)-pyran-4-one (DDMP) and 5-hydroxymethylfurfural (HMF) are two main enolization products in the Maillard reaction and found in some foodstuffs. For many years, whether they are functional or noxious to human health has been a matter of debate. Thus, insight into their formation pathways is important to manage Maillard reaction products. In this study, DDMP and HMF were quantified and compared with regard to their formation and degradation in the d-glucose and l-proline Maillard reaction models using different moisture contents (0, 0.1, 0.5, 1.0, and 4.0mL) at 150 °C for various heating times. DDMP was predominantly generated in dry or low water-content heating models along with n increased 1-deoxyglucosone (1-DG) generation via 2,3-enolization. However, increasing moisture content resulted in a decay of reaction intensity, 1-DG, and DDMP due to a change in the reaction mechanism from 2,3-enolization to 1,2-enolization, which facilitated 3-deoxyglucosone (3-DG) and HMF formation. Increased moisture content in glucose-proline models reduced reaction intensity and also inhibited DDMP and facilitated HMF formation by promoting the pathway change from 2,3-enolization to 1,2-enolization to generate more 3-DG. A water content of 1.0 mL was identified as a critical value, from which the 1,2-enolization became a primary pathway occurring in the Maillard reaction. © 2022 Society of Chemical Industry.

Effect of Aeolian Sand Powder Addition on Frost Resistance of Concrete Pavement.

In order to solve the problem of exploring the freeze-thaw characteristics of modified aeolian sand mixed with cement and silt, the authors propose a freeze-thaw cycle test of modified aeolian sand under the condition of mixing 5% cement and silt with different contents. In this experiment, under freeze-thaw conditions, its intensity decay and mass volume change law and the changes of freeze-thaw characteristics were comprehensively characterized by multiple indicators. The result shows that, after two freeze-thaw cycles, the compressive strength and peak strain of the improved aeolian sand were positively correlated with the silt content. With the increase of the number of freeze-thaw cycles, the compressive and antidestruction capacity of the improved aeolian sand with high silt content and low silt content decreased significantly. 15% silt content improves the structural stability of aeolian sand. It is proved that the authors' experiment can intuitively and effectively reflect the change law of soil strength after freezing and thawing of such improved aeolian sandy soil, which has displayed significance.

Visualization of ex vivo rabbit olfactory mucosa and foramina with three-dimensional optical coherence tomography

There is increasing interest in developing a minimally invasive imaging modality to safely evaluate dynamic microscopic changes of the olfactory mucosa and cribriform foramina. Herein, we utilized three-dimensional (3D) optical coherence tomography (OCT) to characterize the ex vivo stratified substructure of olfactory mucosa in rabbits and create 3D reconstructed images of olfactory foramina. Olfactory mucosa and cribriform plates from four New Zealand White rabbits were dissected and imaged using two swept-source OCT systems: (1) 1.3-µm (μm) center wavelength, 100-nm bandwidth, 200-kHz sweep rate, and (2) 1.7-μm center wavelength, 120-nm bandwidth, 90-kHz sweep rate. Volumetric OCT images were compiled to create a 3D reconstruction of the cribriform plate. The ability of OCT to distinguish the olfactory mucosa substructure and foramina was compared to histology. To estimate imaging penetration depth of each system, the first-order exponential decays of depth-resolved intensity were calculated and compared using a paired t-test. Three-dimensional OCT depicted the stratified layered structures within the olfactory mucosa correlating with histology. The epithelium and lamina propria were measured to be 32μm and 107μm in 1.3-μm OCT compared to 30μm and 105μm in histology. Olfactory foramina were visualized via 3D reconstruction. The 1.7-μm system provided greater depth penetration compared to the 1.3-μm system, allowing for improved foramina visualization. We have shown that OCT can be used to image non-pathologic olfactory mucosa and foramina. Implications for this work include diagnostic and therapeutic potentials for neurorhinological and neurodegenerative diseases.

The effect of decay on churn flow transition in a vertical gas–liquid swirling flow

Gas–liquid two-phase swirl flow has been widely used in industry, especially the decayed swirl flow. However, axial development of the decayed swirl flow which is closely related to the effective length of swirl are lack of understanding. In this work, effects of decay on churn flow transition induced by a vane-typed swirler were investigated by a visualization experiment in a long vertical pipe (inner diameter of 62 mm and total length of 11 m). The results show that under the effect of swirl, churn flow can transform to a swirling annular flow, meanwhile the pressure drop increases and its fluctuation weakens compared with these in the non-swirl churn flow. However, the length of the transformed swirling annular flow is limited, due to the decay of swirl intensity. Then the effect of swirl decay on churn flow transition has been analyzed by the theoretical model proposed by our previous work (Liu et al., 2019). Finally, a new method was proposed here to predict the effective length of swirling annular flow transformed from churn flow in the vertical pipe, by combining the swirl decayed model and churn flow transition model in the swirl flow.

Thermally Stable Red‐Emitting Mixed Halide Perovskite Nanocrystals Enabled by Solid Reaction and Co‐Doping Process

AbstractRapid performance degradation as temperature increases for metal halide perovskite nanocrystals (NCs) greatly restricts the practical application for lighting and display. This problem is even more grievous for the mixed‐halide perovskite NCs because of severe ions migration. Here, a solid‐reaction process in the N2 atmosphere is devised, in which the red‐emitting (631 nm wavelength) mixed halide CsPbBr1.5I1.5 NCs with a coating of SiO2 shell are achieved. Meanwhile, the Zn2+ and K+ ions are co‐doped into the crystal lattice to enhance the radiative decay rate and decrease the trap density of the NCs. The photoluminescence quantum yield of the co‐doped NCs reaches 64.5%, which is one of the highest values for the reported mixed‐halide perovskite NCs obtained by the solid reaction. Importantly, the dopant of K+ enters into the interstitial position of the perovskite structure to increase the structural rigidity, which inhibits exciton–phonon interaction and elevates thermal activation energy, thus improving thermal quenching resistance to sustain high emission intensity at high temperature (&gt;353 K). Furthermore, the red backlight emitting diode based on the NCs exhibits no decay in luminescence intensity after continuous operation for 700 h at 353 K, representing remarkable stability for the commercial application.

Understanding the Interaction between Inorganic and Organic Excitonic Components of an Inorganic‐Organic Nanohybrid Associate

AbstractThe present study deals with the design, formation, and photophysical studies on light‐harvesting inorganic‐organic nanohybrid associates comprising a less‐toxic, inorganic core‐shell QD (Cu−In−S/ZnS) and an organic S0041 dye aggregate. One of the main objectives of this study is to understand the interaction between the inorganic and organic excitonic components of the hybrid system and its implication on the photophysical response of the system. The nanohybrid associate have been obtained through the self‐assembly of S0041 dye molecules (organic exciton) onto Cu−In−S/ZnS QD (inorganic exciton). The characterization of as‐synthesized QD have been done by conventional microscopic and spectroscopic measurements. The exciton domain length for the organic dye aggregates is estimated to be 24 nm. Steady‐state absorption, emission, and time‐resolved photoluminescence (PL) intensity decay measurements have been carried out to understand the interaction mechanism between inorganic and organic excitonic components and the overall photophysical behaviour of the hybrid system. The studies have revealed that the formation of hybrid associate is electrostatically driven and thermodynamically feasible. Interestingly, steady‐state and time‐resolved PL decay measurements and their analysis have revealed that the interaction between inorganic QD and organic aggregate is mediated through dipole‐dipole Förster energy transfer (ET) mechanism and the ET efficiency is found to be as high as 95%. The present system is expected to be used in fabrication of less‐toxic nanoscale light‐harvesting system.

High-sensitivity luminescent thermometer based on Mn4+/Sm3+ dual-emission centers in double-perovskite tellurate

Precise temperature detection utilizing optical parameters is very important and has accelerated scientific researchers to design more suitable materials for non-contact optical thermometers. However, the obstacles of low sensitivity, narrow temperature range, and poor signal discrimination are the main challenges at present. Herein, a dual-mode optical thermometer via the fluorescence intensity ratio (FIR) and decay lifetime was designed in novel double-perovskite Mn4+/Sm3+ co-doped SrGdLiTeO6 (SGLT: Mn4+, Sm3+) luminescent materials. The crystal structure, elemental mapping, elemental valence, and oxygen vacancy were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and electron paramagnetic resonance, respectively. Under 464 nm excitation, the maximum relative sensitivity (SR) values based on the FIR and decay lifetime techniques were estimated as 8.69% K−1@573 K and 1.3% K−1@520 K, respectively. Markedly, the SGLT:1.2%Mn4+, 1.5%Sm3+ phosphor exhibited a good signal discriminability. This work identified a new type of luminescent material to explore rigorous and valid dual-mode optical temperature sensors with a wide range and high sensitivity.

Deciphering Nb98 β decay with the Modular Total Absorption Spectrometer at ORNL

Background: An assessment done under the auspices of the Organization for Economic Co-operation and Developement Nuclear Energy Agency (OECD-NEA) in 2007 suggested that the $\ensuremath{\beta}$ decays of many abundantly produced fission products in nuclear reactors may be incomplete. In this assessment, the fission product $^{98}\mathrm{Nb}$ was assigned the highest priority for study by total absorption spectroscopy due to its large cumulative fission branching fraction and because the $\ensuremath{\beta}$-decay data from several experiments are discrepant.Purpose: To obtain the complete $\ensuremath{\beta}$-decay feeding pattern of $^{98}\mathrm{Nb}$ and determine the impact on the average $\ensuremath{\gamma}$ energy per $^{98}\mathrm{Nb}\phantom{\rule{4pt}{0ex}}\ensuremath{\beta}$ decay and ${\overline{\ensuremath{\nu}}}_{e}$ emission calculations. The complete ${}^{98}\mathrm{Nb}$ $\ensuremath{\beta}$-decay feeding pattern includes ground-state to ground-state $\ensuremath{\beta}$ feeding and direct $\ensuremath{\beta}$ feeding to the ${0}^{+}$ first-excited state (both have no associated $\ensuremath{\gamma}$ rays), and the ground-state to excited-state $\ensuremath{\beta}$ transitions followed by $\ensuremath{\gamma}$ transitions to the ground state of the daughter nucleus, $^{98}\mathrm{Mo}$.Method: The complete $\ensuremath{\beta}$-decay intensities of $^{98}\mathrm{Nb}$ were measured with the Modular Total Absorption Spectrometer at Oak Ridge National Laboratory (ORNL). The $^{98}\mathrm{Nb}$ was produced by the $\ensuremath{\beta}$ decay of mass 98 fission fragments at ORNL's On-Line Test Facility (OLTF) using proton-induced fission of $^{238}\mathrm{U}$.Results: We find that changes to the current ENSDF assessment of $^{98}\mathrm{Nb}\phantom{\rule{4pt}{0ex}}\ensuremath{\beta}$-decay intensity are required. We report improved uncertainties for the $\ensuremath{\beta}$-decay feeding values and report new $\ensuremath{\beta}$ feedings to high-energy levels in $^{98}\mathrm{Mo}$.Conclusions: A more complete $^{98}\mathrm{Nb}\phantom{\rule{4pt}{0ex}}\ensuremath{\beta}$-feeding pattern with improved accuracy and precision is offered. The impacts of the measured changes to the $^{98}\mathrm{Nb}\phantom{\rule{4pt}{0ex}}\ensuremath{\beta}$-feeding pattern on both reactor decay heat calculations and predicted detection rates of reactor ${\overline{\ensuremath{\nu}}}_{e}$ are presented. The Modular Total Absorption Spectrometer measurements of $^{98}\mathrm{Nb}$ demonstrate the importance of reexamining and remeasuring complex $\ensuremath{\beta}$-decaying fission products with total absorption spectroscopy, including nuclei very near $\ensuremath{\beta}$ stability.