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1,270 results on '"Chen, L. Y."'

4. Alcohol intake and the risk of chronic kidney disease: results from a systematic review and dose-response meta-analysis

Author

Yuan, H. C., Yu, Q. T., Bai, H., Xu, H. Z., Gu, P., and Chen, L. Y.

Subjects
Drinking of alcoholic beverages -- Health aspects, Chronic kidney failure -- Risk factors -- Prevention, Food/cooking/nutrition, Health
Abstract

Many prospective cohort studies have investigated the association between the consumption of alcohol and CKD risk and have revealed inconsistent results. In the present study, we aimed to perform a meta-analysis of these studies to assess this association.We searched the PubMed and Embase databases up to 2020 and reviewed the reference lists of relevant articles to identify appropriate studies. We calculated the pooled relative risks with 95% CIs using random effects models, and then performed subgroup and meta-regression analyses. Dose-response meta-analyses were performed by sex separately. We identified 25 eligible prospective cohort studies, including 514,148 participants and 35,585 incident CKD cases. Compared with the category of minimal alcohol intake, light (RR = 0.90, I2 = 49%), moderate (RR = 0.86, I2 = 40%), and heavy (RR = 0.85, I2 = 51%) alcohol intake were associated with a lower risk of CKD. Subgroup meta-analysis by sex indicated that light (RR = 0.92, I2 = 0%), moderate (RR = 0.83, I2 = 39%) and heavy (RR = 0.76, I2 = 40%), alcohol consumption were inversely associated with CKD risk in male. Dose-response meta-analyses detected a nonlinear inverse association between alcohol consumption and the risk of CKD in all participants and linear inverse association in female participants. This meta-analysis shows that light (24 g/day) alcohol consumption are protective against chronic kidney disease in adult participants especially in males., Author(s): H. C. Yuan [sup.1] , Q. T. Yu [sup.2] , H. Bai [sup.2] , H. Z. Xu [sup.3] , P. Gu [sup.1] , L. Y. Chen [sup.3] [sup.4] Author [...]

Published
2021
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6. Electronic and optical properties of novel carbon allotropes

Author

Wang, Zhanyu, Zhang, R. J., Zheng, Y. X., Chen, L. Y., Wang, S. Y., Wang, C. Z., Ho, K. M., Fan, Yuan-Jia, Jin, Bih-Yaw, and Su, Wan-Sheng

Subjects
Condensed Matter - Materials Science
Abstract

The phonon properties, electronic structures and optical properties of novel carbon allotropes, such as monolayer penta-graphene (PG), double-layer PG and T12-carbon, were explored by means of first-principles calculations. Results of phonon calculations demonstrate that these exotic carbon allotropes are dynamically stable. In addition, the bulk T12 phase is an indirect-gap semiconductor having a bandgap of ~4.89 eV. Whereas the bulk material transforms to a 2D phase, the monolayer and double-layer PG become quasi-direct gap semiconductors with smaller band gaps of ~2.64 eV and ~3.27eV, respectively. Furthermore, the partial charge density analysis indicates that the 2D phases retain part of the electronic characteristics of the T12 phase. The linear photon energy-dependent dielectric functions and related optical properties including refractive index, extinction coefficient, absorption spectrum, reflectivity, and energy loss spectrum were also computed and discussed. The structural estimation obtained as well as other findings are in agreement with existing theoretical data. The calculated results are beneficial to the practical applications of these exotic carbon allotropes in optoelectronics and electronics.

Published
2015
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10. Advances in additively manufactured titanium alloys by powder bed fusion and directed energy deposition: Microstructure, defects, and mechanical behavior

Author

Ma, Hongyi Y., Wang, J. C., Qin, Peng, Liu, Y. J., Chen, L. Y., Wang, L. Q., Zhang, Laichang, Ma, Hongyi Y., Wang, J. C., Qin, Peng, Liu, Y. J., Chen, L. Y., Wang, L. Q., and Zhang, Laichang

Abstract

Ti and its alloys have been broadly adopted across various industries owing to their outstanding properties, such as high strength-to-weight ratio, excellent fatigue performance, exceptional corrosion resistance and so on. Additive manufacturing (AM) is a complement to, rather than a replacement for, traditional manufacturing processes. It enhances flexibility in fabricating complex components and resolves machining challenges, resulting in reduced lead times for custom designs. However, owing to distinctions among various AM technologies, Ti alloys fabricated by different AM methods usually present differences in microstructure and defects, which can significantly influence the mechanical performance of built parts. Therefore, having an in-depth knowledge of the scientific aspects of fabrication and material properties is crucial to achieving high-performance Ti alloys through different AM methods. This article reviews the mechanical properties of Ti alloys fabricated by two mainstream powder-type AM techniques: powder bed fusion (PBF) and directed energy deposition (DED). The review examines several key aspects, encompassing phase formation, grain size and morphology, and defects, and provides an in-depth analysis of their influence on the mechanical behaviors of Ti alloys. This review can aid researchers and engineers in selecting appropriate PBF or DED methods and optimizing their process parameters to fabricate high-performance Ti alloys for a wide range of industrial applications.

Published
2024

11. Corrosion and passivation behavior of laser powder bed fusion produced Ti-6Al-4V under various prior plastic deformation strains

Author

Qin, P., Chen, L. Y., Liu, Y. J., Liang, S. X., Sun, H., Zhang, L. C., Qin, P., Chen, L. Y., Liu, Y. J., Liang, S. X., Sun, H., and Zhang, L. C.

Abstract

This work investigated the corrosion behavior of LPBF-produced Ti-6Al-4V under varying compression strains in a 3.5 wt% NaCl solution. It identifies that increasing compression strain causes significant alterations in the acicular a'-Ti phase (coarsening, breakage, and further coarsening). Corrosion resistance decreases with higher strains due to deformed a'-Ti phases, leading to increased film growth kinetics (from 0.09× 10−10 cm2/s increase to 12.75 × 10−10 cm2/s). Samples under higher strains (e.g., 32%) exhibit fluctuations in corrosion behavior due to initiated cracks and subsequent crevice corrosion. These findings are vital for understanding LPBF-produced Ti-6Al-4V in applications requiring mechanical strength and corrosion resilience.

Published
2024

14. Driven Diffusion in Periodic Potentials with Stochastic Path Integral Hyperdynamics

Author

Khandkar, Mahendra D., Chen, L. Y., Ying, S. C., and Ala-Nissila, T.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

We consider the driven diffusion of Brownian particles in 1D periodic potentials using the recently proposed Stochastic Path Integral Hyperdynamics (SPHD) scheme [L.Y. Chen and L.J.M. Horing, J. Chem. Phys. {\bf 126}, 224103 (2007)]. First, we consider the case where a single Brownian particle is moving in a spatially periodic potential and subjected to an external ac driving force. We confirm that there is no stochastic resonance in this system and find that at higher frequencies the diffusion coefficient $D$ is strongly suppressed. The second case is that of a dimer moving in a periodic potential with a static bias. For this case, there's a strong suppression of $D$ when the dimer bond length is an integer multiple of the lattice constant of the potential. For both cases, we demonstrate how the SPHD allows us to extract the dynamical information exactly at different bias levels from a single simulation run, by calculating the corresponding statistical re-weighting factors., Comment: 5 pages, 3 figures

Published
2009

15. Ab initio study on the electronic and magnetic properties of CaFe2As2 within a GGA + negative U approach

Author

Wu, S., Wang, G., Pei, F., Wang, S. Y., Chen, L. Y., Wang, C. Z., and Ho, K. M.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

This paper has been withdrawn by the author due to the error in figure 2, we did not optimized c-value of the supercell, so the results can not give the true physics of this material., Comment: This paper has been withdrawn

Published
2009

17. Conductance of single-atom platinum contacts: Voltage-dependence of the conductance histogram

Author

Nielsen, S. K., Noat, Y., Brandbyge, M., Smit, R. H. M., Hansen, K., Chen, L. Y., Yanson, A. I., Besenbacher, F., and van Ruitenbeek, J. M.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

The conductance of a single-atom contact is sensitive to the coupling of this contact atom to the atoms in the leads. Notably for the transition metals this gives rise to a considerable spread in the observed conductance values. The mean conductance value and spread can be obtained from the first peak in conductance histograms recorded from a large set of contact-breaking cycles. In contrast to the monovalent metals, this mean value for Pt depends strongly on the applied voltage bias and other experimental conditions, ranging from about 1 to 2.5 times 2e^2/h. We propose that the different results in part can be explained by the inclusion of hydrogen in the contacts. The bias dependence of the conductance is on the other hand due to the electron current that destabilizes monatomic Pt chains at high bias., Comment: 4 pages, 4 figures

Published
2002
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18. Econometric inference involving discrete indicator functions

Author

Chen, L.-Y.

Subjects
330
Abstract

This thesis contains four essays on two topics in econometric theory in which inference involving discrete-valued indicator functions is concerned. On the fi…rst topic, I study structural dynamic discrete choice models in which the indicator represents the outcome of a discrete choice made by a forward looking economic agent as a function of utility and other structural objects. The choice is based on an explicitly postulated structural dynamic discrete Markov decision process. An attempt to infer the underlying structural parameters that generates the observed data runs into identifi…cation problems, particularly under nonparameteric and semiparameteric speci…fications. I analyse these problems in Chapter 1 and present new identifi…cation results. In Chapter 2, I propose a semiparametric estimator for the estimation of a …finite horizon structural dynamic discrete choice model. My estimator is constructed based on simultaneous estimation using the method of sieves. I provide and verify sufficient conditions for my structural model to show that the proposed sieve estimator is consistent. On the second topic, I study the use of discrete-valued indicator functions to represent restrictions of one or more inequalities in underlying econometric parameters. I exploit such representation in designing practically applicable procedures of testing econometric restrictions involving multiple inequalities. The method proposed in this thesis is to chain the several hypothesized inequalities on underlying estimable econometric parameters using discrete indicator functions. I then smooth these functions to overcome the distribution problems of discrete functions of continuous variates. Based on this idea, I propose two new methods of testing multiple inequalities restrictions. The linear normal-based chaining method is proposed in Chapter 3 and the quadratic chi-square based chaining method is provided in Chapter 4 as another alternative. Asymptotic properties of both methods are studied and Monte Carlo simulations are also carried out to assess their fi…nite sample performance.

Published
2009

20. Corrosion behavior and mechanism of laser powder bed fusion produced CoCrW in an acidic NaCl solution

Author

Qin, P., Chen, L. Y., Liu, Y. J., Zhao, C. H., Sun, Hongqi, Zhang, Laichang, Qin, P., Chen, L. Y., Liu, Y. J., Zhao, C. H., Sun, Hongqi, and Zhang, Laichang

Abstract

The corrosion behavior and mechanism of the laser powder bed fusion (L-PBF) produced CoCrW were investigated in 0.9 wt% NaCl solution with a pH of 2. The corrosion resistance of the alloy increases after 28 days of immersion because of the formed oxide film, which results in the increased corrosion potential and the decreased passivation current density on the potentiodynamic polarization test. The corrosion mechanism of the L-PBF-produced CoCrW could be explained by the melt pool formed from the laser melting process, that the melt pools were “shrinking” by the formation and dissolution of the oxide film.

Published
2023

21. Corrosion behavior and mechanisms of the heat-treated Ti5Cu produced by laser powder bed fusion

Author

Wang, Xin, Qin, Peng, Chen, L. Y., Sun, Hongqi, Zhang, Laichang, Wang, Xin, Qin, Peng, Chen, L. Y., Sun, Hongqi, and Zhang, Laichang

Abstract

This work investigated the corrosion behavior of laser powder bed fusion produced (LPBFed) Ti5Cu and its heat-treated counterparts at 740 and 900 °C (named as HT-740 and HT-900 respectively) in Hank’s solution. The results indicated that the presence of acicular a'-Ti phase in LPBFed Ti5Cu was beneficial to corrosion, but the corrosion resistance of HT-740 and HT-900 were increased owing to the dual-phase microstructure (a'/a-Ti + Ti2Cu) or the increased content of Ti2Cu phase in the microstructure. The Ti2Cu phase could provide an ‘envelope’ protection to the a'/a-Ti phase and slow down the micro-galvanic reaction between a'/a-Ti phase and Ti2Cu phase.

Published
2023

26. Controlling the crystallization of Nd-doped Bi4Ti3O12 thin-films for lead-free energy storage capacitors.

Author

Song, D. P., Yang, J., Sun, J. X., Chen, L.-Y., Chu, Y. Q., Wang, Y., and Lee, J.-K.

Subjects
ENERGY storage, CAPACITORS, ENERGY density, FERROELECTRIC materials, DIELECTRIC thin films, FERROELECTRIC thin films, PIEZOELECTRIC thin films, ANNEALING of metals
Abstract

Environmentally benign non-lead-based dielectric thin film capacitors with high electrostatic energy density, long-term stability, and fast charge/discharge capability are strongly demanded in advanced electrical and pulsed power devices. Here, we propose that insufficient crystallization is an effective method to achieve high energy storage performance. A high efficiency of 84.3%, together with a good energy density of 41.6 J / cm 3 and an excellent fatigue endurance, is obtained in a lead-free Nd-doped Bi 4 Ti 3 O 12 film of low crystallization. An increase in the annealing temperature increases the crystallinity and grain size, which improves the ferroelectric polarization of a thin film. A narrow hysteresis loop with large maximum polarization and small remnant polarization is obtained in the insufficiently crystallized film, which is annealed in the intermediate temperature. This film also shows a lower leakage current compared with the fully crystallized counterpart due to the less defective microstructure. This work provides a straightforward and executable method to design ferroelectric materials for the applications of energy storage capacitors. [ABSTRACT FROM AUTHOR]

Published
2020
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32. Concomitant modulation of interlayer exchange coupling and Gilbert damping in Fe/CoO with spin conductor Ag layer at interface.

Author

He, J., Zhao, Z. R., Xia, H., Li, T., Liang, E., Ni, G., Wang, J., Sheng, C. X., Chen, L. Y., Wu, Y. Z., and Zhao, H. B.

Subjects
CONDUCTORS (Musicians), KERR magneto-optical effect, MOMENTUM transfer, INTERFACE dynamics, ANGULAR momentum (Mechanics)
Abstract

We report on the modulation of interlayer exchange coupling (IEC) between the ferromagnet (FM) Fe and insulating antiferromagnet (AFM) CoO and its impact on the Gilbert damping by a time-resolved magneto-optical Kerr effect technique. By inserting a wedge spin conductor Ag layer at the interface of Fe/CoO, it is revealed that both uniform spin precession frequency and Gilbert damping constant of Fe film decrease with increasing Ag thickness up to ∼2 nm, and above that with eliminated IEC, these two parameters reach the intrinsic values of the Fe film. The precession frequency and damping also show similar variation tendency with temperature for attenuated IEC. These results prove that the exchange coupling at the FM–AFM interface plays an essential role for the spin angular momentum transfer to the insulating AFM layer, and the spin pumping is insignificant even for the very thin spin conductor layer. Our findings may have general insights into the role of the FM/AFM interface in the magnetization dynamics and spin angular momentum transfer for future spintronic applications. [ABSTRACT FROM AUTHOR]

Published
2023
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36. Toward Precision Education: Educational Data Mining and Learning Analytics for Identifying Students’ Learning Patterns with Ebook Systems

Author

Yang, C. Y. Christopher, Chen, L. Y. Irene, and Ogata, Hiroaki

Subjects
Educational data mining, ComputingMilieux_COMPUTERSANDEDUCATION, Precision education, Learning pattern, Ebook learning log, Learning analytics
Abstract

Precision education is now recognized as a new challenge of applying artificial intelligence, machine learning, and learning analytics to improve both learning performance and teaching quality. To promote precision education, digital learning platforms have been widely used to collect educational records of students’ behavior, performance, and other types of interaction. On the other hand, the increasing volume of students’ learning behavioral data in virtual learning environments provides opportunities for mining data on these students’ learning patterns. Accordingly, identifying students’ online learning patterns on various digital learning platforms has drawn the interest of the learning analytics and educational data mining research communities. In this study, the authors applied data analytics methods to examine the learning patterns of students using an ebook system for one semester in an undergraduate course. The authors used a clustering approach to identify subgroups of students with different learning patterns. Several subgroups were identified, and the students’ learning patterns in each subgroup were determined accordingly. In addition, the association between these students’ learning patterns and their learning outcomes from the course was investigated. The findings of this study provide educators opportunities to predict students’ learning outcomes by analyzing their online learning behaviors and providing timely intervention for improving their learning experience, which achieves one of the goals of learning analytics as part of precision education.

Published
2021

37. Resting heart rate and incident atrial fibrillation: A stratified Mendelian randomization in the AFGen consortium

Author

Siland, J. E., primary, Geelhoed, B., additional, Roselli, C., additional, Wang, B., additional, Lin, H. J., additional, Weiss, S., additional, Trompet, S., additional, van den Berg, M. E., additional, Soliman, E. Z., additional, Chen, L. Y., additional, Ford, I., additional, Jukema, J. W., additional, Macfarlane, P. W., additional, Kornej, J., additional, Lin, H., additional, Lunetta, K. L., additional, Kavousi, M., additional, Kors, J. A., additional, Ikram, M. A., additional, Guo, X., additional, Yao, J., additional, Dörr, M., additional, Felix, S. B., additional, Völker, U., additional, Sotoodehnia, N., additional, Arking, D. E., additional, Stricker, B. H., additional, Heckbert, S. R., additional, Lubitz, S. A., additional, Benjamin, E. J., additional, Alonso, A., additional, Ellinor, P. T., additional, van der Harst, P., additional, and Rienstra, M., additional

Published
2022
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38. Expression of Viral Entry Proteins and In Vitro Susceptibility of Pulmonary Vascular Endothelium to SARS CoV 2 Infection

Author

Long, A., primary, Dougherty, E., additional, Chen, L.-Y., additional, Qi, L., additional, Warner, S., additional, Lafont, B., additional, Lackemeyer, N., additional, Johnson, R., additional, Altan-Bonnet, N., additional, Keshavarz, A., additional, Strich, J.R., additional, Danner, R.L., additional, Taubenberger, J., additional, and Elinoff, J.M., additional

Published
2022
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40. Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

Author

Abu-Shawareb, H, Acree, R, Adams, P, Adams, J, Addis, B, Aden, R, Adrian, P, Afeyan, BB, Aggleton, M, Aghaian, L, Aguirre, A, Aikens, D, Akre, J, Albert, F, Albrecht, M, Albright, BJ, Albritton, J, Alcala, J, Alday, C, Alessi, DA, Alexander, N, Alfonso, J, Alfonso, N, Alger, E, Ali, SJ, Ali, ZA, Alley, WE, Amala, P, Amendt, PA, Amick, P, Ammula, S, Amorin, C, Ampleford, DJ, Anderson, RW, Anklam, T, Antipa, N, Appelbe, B, Aracne-Ruddle, C, Araya, E, Arend, M, Arnold, P, Arnold, T, Asay, J, Atherton, LJ, Atkinson, D, Atkinson, R, Auerbach, JM, Austin, B, Auyang, L, Awwal, AS, Ayers, J, Ayers, S, Ayers, T, Azevedo, S, Bachmann, B, Back, CA, Bae, J, Bailey, DS, Bailey, J, Baisden, T, Baker, KL, Baldis, H, Barber, D, Barberis, M, Barker, D, Barnes, A, Barnes, CW, Barrios, MA, Barty, C, Bass, I, Batha, SH, Baxamusa, SH, Bazan, G, Beagle, JK, Beale, R, Beck, BR, Beck, JB, Bedzyk, M, Beeler, RG, Behrendt, W, Belk, L, Bell, P, Belyaev, M, Benage, JF, Bennett, G, Benedetti, LR, Benedict, LX, Berger, R, Bernat, T, Bernstein, LA, Berry, B, Bertolini, L, Besenbruch, G, Betcher, J, Bettenhausen, R, Betti, R, Bezzerides, B, Bhandarkar, SD, Bickel, R, Biener, J, Biesiada, T, Bigelow, K, Bigelow-Granillo, J, Bigman, V, Bionta, RM, Birge, NW, Bitter, M, Black, AC, Bleile, R, Bleuel, DL, Bliss, E, Blue, B, Boehly, T, Boehm, K, Boley, CD, Bonanno, R, Bond, EJ, Bond, T, Bonino, MJ, Borden, M, Bourgade, J-L, Bousquet, J, Bowers, J, Bowers, M, Boyd, R, Bozek, A, Bradley, DK, Bradley, KS, Bradley, PA, Bradley, L, Brannon, L, Brantley, PS, Braun, D, Braun, T, Brienza-Larsen, K, Briggs, TM, Britten, J, Brooks, ED, Browning, D, Bruhn, MW, Brunner, TA, Bruns, H, Brunton, G, Bryant, B, Buczek, T, Bude, J, Buitano, L, Burkhart, S, Burmark, J, Burnham, A, Burr, R, Busby, LE, Butlin, B, Cabeltis, R, Cable, M, Cabot, WH, Cagadas, B, Caggiano, J, Cahayag, R, Caldwell, SE, Calkins, S, Callahan, DA, Calleja-Aguirre, J, Camara, L, Camp, D, Campbell, EM, Campbell, JH, Carey, B, Carey, R, Carlisle, K, Carlson, L, Carman, L, Carmichael, J, Carpenter, A, Carr, C, Carrera, JA, Casavant, D, Casey, A, Casey, DT, Castillo, A, Castillo, E, Castor, JI, Castro, C, Caughey, W, Cavitt, R, Celeste, J, Celliers, PM, Cerjan, C, Chandler, G, Chang, B, Chang, C, Chang, J, Chang, L, Chapman, R, Chapman, T, Chase, L, Chen, H, Chen, K, Chen, L-Y, Cheng, B, Chittenden, J, Choate, C, Chou, J, Chrien, RE, Chrisp, M, Christensen, K, Christensen, M, Christopherson, AR, Chung, M, Church, JA, Clark, A, Clark, DS, Clark, K, Clark, R, Claus, L, Cline, B, Cline, JA, Cobble, JA, Cochrane, K, Cohen, B, Cohen, S, Collette, MR, Collins, G, Collins, LA, Collins, TJB, Conder, A, Conrad, B, Conyers, M, Cook, AW, Cook, D, Cook, R, Cooley, JC, Cooper, G, Cope, T, Copeland, SR, Coppari, F, Cortez, J, Cox, J, Crandall, DH, Crane, J, Craxton, RS, Cray, M, Crilly, A, Crippen, JW, Cross, D, Cuneo, M, Cuotts, G, Czajka, CE, Czechowicz, D, Daly, T, Danforth, P, Darbee, R, Darlington, B, Datte, P, Dauffy, L, Davalos, G, Davidovits, S, Davis, P, Davis, J, Dawson, S, Day, RD, Day, TH, Dayton, M, Deck, C, Decker, C, Deeney, C, DeFriend, KA, Deis, G, Delamater, ND, Delettrez, JA, Demaret, R, Demos, S, Dempsey, SM, Desjardin, R, Desjardins, T, Desjarlais, MP, Dewald, EL, DeYoreo, J, Diaz, S, Dimonte, G, Dittrich, TR, Divol, L, Dixit, SN, Dixon, J, Dodd, ES, Dolan, D, Donovan, A, Donovan, M, Döppner, T, Dorrer, C, Dorsano, N, Douglas, MR, Dow, D, Downie, J, Downing, E, Dozieres, M, Draggoo, V, Drake, D, Drake, RP, Drake, T, Dreifuerst, G, DuBois, DF, DuBois, PF, Dunham, G, Dylla-Spears, R, Dymoke-Bradshaw, AKL, Dzenitis, B, Ebbers, C, Eckart, M, Eddinger, S, Eder, D, Edgell, D, Edwards, MJ, Efthimion, P, Eggert, JH, Ehrlich, B, Ehrmann, P, Elhadj, S, Ellerbee, C, Elliott, NS, Ellison, CL, Elsner, F, Emerich, M, Engelhorn, K, England, T, English, E, Epperson, P, Epstein, R, Erbert, G, Erickson, MA, Erskine, DJ, Erlandson, A, Espinosa, RJ, Estes, C, Estabrook, KG, Evans, S, Fabyan, A, Fair, J, Fallejo, R, Farmer, N, Farmer, WA, Farrell, M, Fatherley, VE, Fedorov, M, Feigenbaum, E, Feit, M, Ferguson, W, Fernandez, JC, Fernandez-Panella, A, Fess, S, Field, JE, Filip, CV, Fincke, JR, Finn, T, Finnegan, SM, Finucane, RG, Fischer, M, Fisher, A, Fisher, J, Fishler, B, Fittinghoff, D, Fitzsimmons, P, Flegel, M, Flippo, KA, Florio, J, Folta, J, Folta, P, Foreman, LR, Forrest, C, Forsman, A, Fooks, J, Foord, M, Fortner, R, Fournier, K, Fratanduono, DE, Frazier, N, Frazier, T, Frederick, C, Freeman, MS, Frenje, J, Frey, D, Frieders, G, Friedrich, S, Froula, DH, Fry, J, Fuller, T, Gaffney, J, Gales, S, Le Galloudec, B, Le Galloudec, KK, Gambhir, A, Gao, L, Garbett, WJ, Garcia, A, Gates, C, Gaut, E, Gauthier, P, Gavin, Z, Gaylord, J, Geissel, M, Génin, F, Georgeson, J, Geppert-Kleinrath, H, Geppert-Kleinrath, V, Gharibyan, N, Gibson, J, Gibson, C, Giraldez, E, Glebov, V, Glendinning, SG, Glenn, S, Glenzer, SH, Goade, S, Gobby, PL, Goldman, SR, Golick, B, Gomez, M, Goncharov, V, Goodin, D, Grabowski, P, Grafil, E, Graham, P, Grandy, J, Grasz, E, Graziani, F, Greenman, G, Greenough, JA, Greenwood, A, Gregori, G, Green, T, Griego, JR, Grim, GP, Grondalski, J, Gross, S, Guckian, J, Guler, N, Gunney, B, Guss, G, Haan, S, Hackbarth, J, Hackel, L, Hackel, R, Haefner, C, Hagmann, C, Hahn, KD, Hahn, S, Haid, BJ, Haines, BM, Hall, BM, Hall, C, Hall, GN, Hamamoto, M, Hamel, S, Hamilton, CE, Hammel, BA, Hammer, JH, Hampton, G, Hamza, A, Handler, A, Hansen, S, Hanson, D, Haque, R, Harding, D, Harding, E, Hares, JD, Harris, DB, Harte, JA, Hartouni, EP, Hatarik, R, Hatchett, S, Hauer, AA, Havre, M, Hawley, R, Hayes, J, Hayes, S, Hayes-Sterbenz, A, Haynam, CA, Haynes, DA, Headley, D, Heal, A, Heebner, JE, Heerey, S, Heestand, GM, Heeter, R, Hein, N, Heinbockel, C, Hendricks, C, Henesian, M, Heninger, J, Henrikson, J, Henry, EA, Herbold, EB, Hermann, MR, Hermes, G, Hernandez, JE, Hernandez, VJ, Herrmann, MC, Herrmann, HW, Herrera, OD, Hewett, D, Hibbard, R, Hicks, DG, Hill, D, Hill, K, Hilsabeck, T, Hinkel, DE, Ho, DD, Ho, VK, Hoffer, JK, Hoffman, NM, Hohenberger, M, Hohensee, M, Hoke, W, Holdener, D, Holdener, F, Holder, JP, Holko, B, Holunga, D, Holzrichter, JF, Honig, J, Hoover, D, Hopkins, D, Berzak Hopkins, L, Hoppe, M, Hoppe, ML, Horner, J, Hornung, R, Horsfield, CJ, Horvath, J, Hotaling, D, House, R, Howell, L, Hsing, WW, Hu, SX, Huang, H, Huckins, J, Hui, H, Humbird, KD, Hund, J, Hunt, J, Hurricane, OA, Hutton, M, Huynh, KH-K, Inandan, L, Iglesias, C, Igumenshchev, IV, Izumi, N, Jackson, M, Jackson, J, Jacobs, SD, James, G, Jancaitis, K, Jarboe, J, Jarrott, LC, Jasion, D, Jaquez, J, Jeet, J, Jenei, AE, Jensen, J, Jimenez, J, Jimenez, R, Jobe, D, Johal, Z, Johns, HM, Johnson, D, Johnson, MA, Gatu Johnson, M, Johnson, RJ, Johnson, S, Johnson, SA, Johnson, T, Jones, K, Jones, O, Jones, M, Jorge, R, Jorgenson, HJ, Julian, M, Jun, BI, Jungquist, R, Kaae, J, Kabadi, N, Kaczala, D, Kalantar, D, Kangas, K, Karasiev, VV, Karasik, M, Karpenko, V, Kasarky, A, Kasper, K, Kauffman, R, Kaufman, MI, Keane, C, Keaty, L, Kegelmeyer, L, Keiter, PA, Kellett, PA, Kellogg, J, Kelly, JH, Kemic, S, Kemp, AJ, Kemp, GE, Kerbel, GD, Kershaw, D, Kerr, SM, Kessler, TJ, Key, MH, Khan, SF, Khater, H, Kiikka, C, Kilkenny, J, Kim, Y, Kim, Y-J, Kimko, J, Kimmel, M, Kindel, JM, King, J, Kirkwood, RK, Klaus, L, Klem, D, Kline, JL, Klingmann, J, Kluth, G, Knapp, P, Knauer, J, Knipping, J, Knudson, M, Kobs, D, Koch, J, Kohut, T, Kong, C, Koning, JM, Koning, P, Konior, S, Kornblum, H, Kot, LB, Kozioziemski, B, Kozlowski, M, Kozlowski, PM, Krammen, J, Krasheninnikova, NS, Kraus, B, Krauser, W, Kress, JD, Kritcher, AL, Krieger, E, Kroll, JJ, Kruer, WL, Kruse, MKG, Kucheyev, S, Kumbera, M, Kumpan, S, Kunimune, J, Kustowski, B, Kwan, TJT, Kyrala, GA, Laffite, S, Lafon, M, LaFortune, K, Lahmann, B, Lairson, B, Landen, OL, Langenbrunner, J, Lagin, L, Land, T, Lane, M, Laney, D, Langdon, AB, Langer, SH, Langro, A, Lanier, NE, Lanier, TE, Larson, D, Lasinski, BF, Lassle, D, LaTray, D, Lau, G, Lau, N, Laumann, C, Laurence, A, Laurence, TA, Lawson, J, Le, HP, Leach, RR, Leal, L, Leatherland, A, LeChien, K, Lechleiter, B, Lee, A, Lee, M, Lee, T, Leeper, RJ, Lefebvre, E, Leidinger, J-P, LeMire, B, Lemke, RW, Lemos, NC, Le Pape, S, Lerche, R, Lerner, S, Letts, S, Levedahl, K, Lewis, T, Li, CK, Li, H, Li, J, Liao, W, Liao, ZM, Liedahl, D, Liebman, J, Lindford, G, Lindman, EL, Lindl, JD, Loey, H, London, RA, Long, F, Loomis, EN, Lopez, FE, Lopez, H, Losbanos, E, Loucks, S, Lowe-Webb, R, Lundgren, E, Ludwigsen, AP, Luo, R, Lusk, J, Lyons, R, Ma, T, Macallop, Y, MacDonald, MJ, MacGowan, BJ, Mack, JM, Mackinnon, AJ, MacLaren, SA, MacPhee, AG, Magelssen, GR, Magoon, J, Malone, RM, Malsbury, T, Managan, R, Mancini, R, Manes, K, Maney, D, Manha, D, Mannion, OM, Manuel, AM, Mapoles, E, Mara, G, Marcotte, T, Marin, E, Marinak, MM, Mariscal, C, Mariscal, DA, Mariscal, EF, Marley, EV, Marozas, JA, Marquez, R, Marshall, CD, Marshall, FJ, Marshall, M, Marshall, S, Marticorena, J, Martinez, D, Maslennikov, I, Mason, D, Mason, RJ, Masse, L, Massey, W, Masson-Laborde, P-E, Masters, ND, Mathisen, D, Mathison, E, Matone, J, Matthews, MJ, Mattoon, C, Mattsson, TR, Matzen, K, Mauche, CW, Mauldin, M, McAbee, T, McBurney, M, Mccarville, T, McCrory, RL, McEvoy, AM, McGuffey, C, Mcinnis, M, McKenty, P, McKinley, MS, McLeod, JB, McPherson, A, Mcquillan, B, Meamber, M, Meaney, KD, Meezan, NB, Meissner, R, Mehlhorn, TA, Mehta, NC, Menapace, J, Merrill, FE, Merritt, BT, Merritt, EC, Meyerhofer, DD, Mezyk, S, Mich, RJ, Michel, PA, Milam, D, Miller, C, Miller, D, Miller, DS, Miller, E, Miller, EK, Miller, J, Miller, M, Miller, PE, Miller, T, Miller, W, Miller-Kamm, V, Millot, M, Milovich, JL, Minner, P, Miquel, J-L, Mitchell, S, Molvig, K, Montesanti, RC, Montgomery, DS, Monticelli, M, Montoya, A, Moody, JD, Moore, AS, Moore, E, Moran, M, Moreno, JC, Moreno, K, Morgan, BE, Morrow, T, Morton, JW, Moses, E, Moy, K, Muir, R, Murillo, MS, Murray, JE, Murray, JR, Munro, DH, Murphy, TJ, Munteanu, FM, Nafziger, J, Nagayama, T, Nagel, SR, Nast, R, Negres, RA, Nelson, A, Nelson, D, Nelson, J, Nelson, S, Nemethy, S, Neumayer, P, Newman, K, Newton, M, Nguyen, H, Di Nicola, J-MG, Di Nicola, P, Niemann, C, Nikroo, A, Nilson, PM, Nobile, A, Noorai, V, Nora, R, Norton, M, Nostrand, M, Note, V, Novell, S, Nowak, PF, Nunez, A, Nyholm, RA, O'Brien, M, Oceguera, A, Oertel, JA, Okui, J, Olejniczak, B, Oliveira, J, Olsen, P, Olson, B, Olson, K, Olson, RE, Opachich, YP, Orsi, N, Orth, CD, Owen, M, Padalino, S, Padilla, E, Paguio, R, Paguio, S, Paisner, J, Pajoom, S, Pak, A, Palaniyappan, S, Palma, K, Pannell, T, Papp, F, Paras, D, Parham, T, Park, H-S, Pasternak, A, Patankar, S, Patel, MV, Patel, PK, Patterson, R, Patterson, S, Paul, B, Paul, M, Pauli, E, Pearce, OT, Pearcy, J, Pedrotti, B, Peer, A, Pelz, LJ, Penetrante, B, Penner, J, Perez, A, Perkins, LJ, Pernice, E, Perry, TS, Person, S, Petersen, D, Petersen, T, Peterson, DL, Peterson, EB, Peterson, JE, Peterson, JL, Peterson, K, Peterson, RR, Petrasso, RD, Philippe, F, Phipps, TJ, Piceno, E, Ping, Y, Pickworth, L, Pino, J, Plummer, R, Pollack, GD, Pollaine, SM, Pollock, BB, Ponce, D, Ponce, J, Pontelandolfo, J, Porter, JL, Post, J, Poujade, O, Powell, C, Powell, H, Power, G, Pozulp, M, Prantil, M, Prasad, M, Pratuch, S, Price, S, Primdahl, K, Prisbrey, S, Procassini, R, Pruyne, A, Pudliner, B, Qiu, SR, Quan, K, Quinn, M, Quintenz, J, Radha, PB, Rainer, F, Ralph, JE, Raman, KS, Raman, R, Rambo, P, Rana, S, Randewich, A, Rardin, D, Ratledge, M, Ravelo, N, Ravizza, F, Rayce, M, Raymond, A, Raymond, B, Reed, B, Reed, C, Regan, S, Reichelt, B, Reis, V, Reisdorf, S, Rekow, V, Remington, BA, Rendon, A, Requieron, W, Rever, M, Reynolds, H, Reynolds, J, Rhodes, J, Rhodes, M, Richardson, MC, Rice, B, Rice, NG, Rieben, R, Rigatti, A, Riggs, S, Rinderknecht, HG, Ring, K, Riordan, B, Riquier, R, Rivers, C, Roberts, D, Roberts, V, Robertson, G, Robey, HF, Robles, J, Rocha, P, Rochau, G, Rodriguez, J, Rodriguez, S, Rosen, M, Rosenberg, M, Ross, G, Ross, JS, Ross, P, Rouse, J, Rovang, D, Rubenchik, AM, Rubery, MS, Ruiz, CL, Rushford, M, Russ, B, Rygg, JR, Ryujin, BS, Sacks, RA, Sacks, RF, Saito, K, Salmon, T, Salmonson, JD, Sanchez, J, Samuelson, S, Sanchez, M, Sangster, C, Saroyan, A, Sater, J, Satsangi, A, Sauers, S, Saunders, R, Sauppe, JP, Sawicki, R, Sayre, D, Scanlan, M, Schaffers, K, Schappert, GT, Schiaffino, S, Schlossberg, DJ, Schmidt, DW, Schmitt, MJ, Schneider, DHG, Schneider, MB, Schneider, R, Schoff, M, Schollmeier, M, Schölmerich, M, Schroeder, CR, Schrauth, SE, Scott, HA, Scott, I, Scott, JM, Scott, RHH, Scullard, CR, Sedillo, T, Seguin, FH, Seka, W, Senecal, J, Sepke, SM, Seppala, L, Sequoia, K, Severyn, J, Sevier, JM, Sewell, N, Seznec, S, Shah, RC, Shamlian, J, Shaughnessy, D, Shaw, M, Shaw, R, Shearer, C, Shelton, R, Shen, N, Sherlock, MW, Shestakov, AI, Shi, EL, Shin, SJ, Shingleton, N, Shmayda, W, Shor, M, Shoup, M, Shuldberg, C, Siegel, L, Silva, FJ, Simakov, AN, Sims, BT, Sinars, D, Singh, P, Sio, H, Skulina, K, Skupsky, S, Slutz, S, Sluyter, M, Smalyuk, VA, Smauley, D, Smeltser, RM, Smith, C, Smith, I, Smith, J, Smith, L, Smith, R, Sohn, R, Sommer, S, Sorce, C, Sorem, M, Soures, JM, Spaeth, ML, Spears, BK, Speas, S, Speck, D, Speck, R, Spears, J, Spinka, T, Springer, PT, Stadermann, M, Stahl, B, Stahoviak, J, Stanton, LG, Steele, R, Steele, W, Steinman, D, Stemke, R, Stephens, R, Sterbenz, S, Sterne, P, Stevens, D, Stevers, J, Still, CB, Stoeckl, C, Stoeffl, W, Stolken, JS, Stolz, C, Storm, E, Stone, G, Stoupin, S, Stout, E, Stowers, I, Strauser, R, Streckart, H, Streit, J, Strozzi, DJ, Suratwala, T, Sutcliffe, G, Suter, LJ, Sutton, SB, Svidzinski, V, Swadling, G, Sweet, W, Szoke, A, Tabak, M, Takagi, M, Tambazidis, A, Tang, V, Taranowski, M, Taylor, LA, Telford, S, Theobald, W, Thi, M, Thomas, A, Thomas, CA, Thomas, I, Thomas, R, Thompson, IJ, Thongstisubskul, A, Thorsness, CB, Tietbohl, G, Tipton, RE, Tobin, M, Tomlin, N, Tommasini, R, Toreja, AJ, Torres, J, Town, RPJ, Townsend, S, Trenholme, J, Trivelpiece, A, Trosseille, C, Truax, H, Trummer, D, Trummer, S, Truong, T, Tubbs, D, Tubman, ER, Tunnell, T, Turnbull, D, Turner, RE, Ulitsky, M, Upadhye, R, Vaher, JL, VanArsdall, P, VanBlarcom, D, Vandenboomgaerde, M, VanQuinlan, R, Van Wonterghem, BM, Varnum, WS, Velikovich, AL, Vella, A, Verdon, CP, Vermillion, B, Vernon, S, Vesey, R, Vickers, J, Vignes, RM, Visosky, M, Vocke, J, Volegov, PL, Vonhof, S, Von Rotz, R, Vu, HX, Vu, M, Wall, D, Wall, J, Wallace, R, Wallin, B, Walmer, D, Walsh, CA, Walters, CF, Waltz, C, Wan, A, Wang, A, Wang, Y, Wark, JS, Warner, BE, Watson, J, Watt, RG, Watts, P, Weaver, J, Weaver, RP, Weaver, S, Weber, CR, Weber, P, Weber, SV, Wegner, P, Welday, B, Welser-Sherrill, L, Weiss, K, Widmann, K, Wheeler, GF, Whistler, W, White, RK, Whitley, HD, Whitman, P, Wickett, ME, Widmayer, C, Wiedwald, J, Wilcox, R, Wilcox, S, Wild, C, Wilde, BH, Wilde, CH, Wilhelmsen, K, Wilke, MD, Wilkens, H, Wilkins, P, Wilks, SC, Williams, EA, Williams, GJ, Williams, W, Williams, WH, Wilson, DC, Wilson, B, Wilson, E, Wilson, R, Winters, S, Wisoff, J, Wittman, M, Wolfe, J, Wong, A, Wong, KW, Wong, L, Wong, N, Wood, R, Woodhouse, D, Woodruff, J, Woods, DT, Woods, S, Woodworth, BN, Wooten, E, Wootton, A, Work, K, Workman, JB, Wright, J, Wu, M, Wuest, C, Wysocki, FJ, Xu, H, Yamaguchi, M, Yang, B, Yang, ST, Yatabe, J, Yeamans, CB, Yee, BC, Yi, SA, Yin, L, Young, B, Young, CS, Young, CV, Young, P, Youngblood, K, Zacharias, R, Zagaris, G, Zaitseva, N, Zaka, F, Ze, F, Zeiger, B, Zika, M, Zimmerman, GB, Zobrist, T, Zuegel, JD, Zylstra, AB, Indirect Drive ICF Collaboration, Collaboration, Indirect Drive ICF, AWE Plc, Lawrence Livermore National Laboratory, and U.S Department of Energy

Subjects
General Physics, 02 Physical Sciences, General Physics and Astronomy, Indirect Drive ICF Collaboration, 01 Mathematical Sciences, 09 Engineering
Abstract

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Published
2022

41. Energy storage in BaBi4Ti4O15 thin films with high efficiency.

Author

Song, D. P., Wang, Y., Chen, L.-Y., Wang, F., Yang, J., Yang, B. B., and Zhu, X. B.

Subjects
FERROELECTRIC thin films, HYSTERESIS loop, ENERGY density, ELECTRICAL energy, HYBRID electric vehicles, GRAIN size, CHEMICAL solution deposition
Abstract

A ferroelectric film with slim polarization-electric (P-E) hysteresis loops, showing small remanent polarization (P r) and large saturated polarization (P s), is desired to obtain high recoverable energy density (U r e ) and efficiency (η) in thin film capacitors. Here, small P r and large P m values are achieved in BaBi 4 Ti 4 O 15 thin films through modulating film grain size. A large U r e of 44.3 J / cm 3 as well as a high η of 87.1% is obtained. In addition, the derived BaBi 4 Ti 4 O 15 thin films show excellent energy storage performance in wide frequency range, thermal stability, and fatigue endurance. These results suggest that BaBi 4 Ti 4 O 15 films can be considered as a candidate for dielectric energy storage capacitors, and the route through grain size optimization is a promising strategy to improve the capacitive performance of ferroelectric materials. [ABSTRACT FROM AUTHOR]

Published
2019
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42. Resting heart rate and incident atrial fibrillation:A stratified Mendelian randomization in the AFGen consortium

Author

Siland, J. E., Geelhoed, B., Roselli, C., Wang, B., Lin, H., Weiss, S., Trompet, S., van den Berg, M. E., Soliman, E. Z., Chen, L. Y., Ford, I., Jukema, J. W., Macfarlane, P. W., Kornej, J., Lunetta, K. L., Kavousi, M., Kors, J. A., Ikram, M. A., Guo, X., Yao, J., Dörr, M., Felix, S. B., Völker, U., Sotoodehnia, N., Arking, D. E., Stricker, B. H., Heckbert, S. R., Benjamin, E. J., Lubitz, S. A., Alonso, A., Ellinor, P. T., van der Harst, P., Rienstra, M., Siland, J. E., Geelhoed, B., Roselli, C., Wang, B., Lin, H., Weiss, S., Trompet, S., van den Berg, M. E., Soliman, E. Z., Chen, L. Y., Ford, I., Jukema, J. W., Macfarlane, P. W., Kornej, J., Lunetta, K. L., Kavousi, M., Kors, J. A., Ikram, M. A., Guo, X., Yao, J., Dörr, M., Felix, S. B., Völker, U., Sotoodehnia, N., Arking, D. E., Stricker, B. H., Heckbert, S. R., Benjamin, E. J., Lubitz, S. A., Alonso, A., Ellinor, P. T., van der Harst, P., and Rienstra, M.

Abstract

Background Both elevated and low resting heart rates are associated with atrial fibrillation (AF), suggesting a U-shaped relationship. However, evidence for a U-shaped causal association between genetically-determined resting heart rate and incident AF is limited. We investigated potential directional changes of the causal association between genetically-determined resting heart rate and incident AF. Method and results Seven cohorts of the AFGen consortium contributed data to this meta-analysis. All participants were of European ancestry with known AF status, genotype information, and a heart rate measurement from a baseline electrocardiogram (ECG). Three strata of instrumental variable-free resting heart rate were used to assess possible non-linear associations between genetically-determined resting heart rate and the logarithm of the incident AF hazard rate: <65; 65–75; and >75 beats per minute (bpm). Mendelian randomization analyses using a weighted resting heart rate polygenic risk score were performed for each stratum. We studied 38,981 individuals (mean age 59±10 years, 54% women) with a mean resting heart rate of 67±11 bpm. During a mean follow-up of 13±5 years, 4,779 (12%) individuals developed AF. A U-shaped association between the resting heart rate and the incident AF-hazard ratio was observed. Genetically-determined resting heart rate was inversely associated with incident AF for instrumental variable-free resting heart rates below 65 bpm (hazard ratio for genetically-determined resting heart rate, 0.96; 95% confidence interval, 0.94–0.99; p = 0.01). Genetically-determined resting heart rate was not associated with incident AF in the other two strata. Conclusions For resting heart rates below 65 bpm, our results support an inverse causal association between genetically-determined resting heart rate and incident AF.

Published
2022

43. Resting heart rate and incident atrial fibrillation: A stratified Mendelian randomization in the AFGen consortium

Author

Circulatory Health, Team Medisch, Siland, J E, Geelhoed, B, Roselli, C, Wang, B, Lin, H J, Weiss, S, Trompet, S, van den Berg, M E, Soliman, E Z, Chen, L Y, Ford, I, Jukema, J W, Macfarlane, P W, Kornej, J, Lin, H, Lunetta, K L, Kavousi, M, Kors, J A, Ikram, M A, Guo, X, Yao, J, Dörr, M, Felix, S B, Völker, U, Sotoodehnia, N, Arking, D E, Stricker, B H, Heckbert, S R, Lubitz, S A, Benjamin, E J, Alonso, A, Ellinor, P T, van der Harst, P, Rienstra, M, Circulatory Health, Team Medisch, Siland, J E, Geelhoed, B, Roselli, C, Wang, B, Lin, H J, Weiss, S, Trompet, S, van den Berg, M E, Soliman, E Z, Chen, L Y, Ford, I, Jukema, J W, Macfarlane, P W, Kornej, J, Lin, H, Lunetta, K L, Kavousi, M, Kors, J A, Ikram, M A, Guo, X, Yao, J, Dörr, M, Felix, S B, Völker, U, Sotoodehnia, N, Arking, D E, Stricker, B H, Heckbert, S R, Lubitz, S A, Benjamin, E J, Alonso, A, Ellinor, P T, van der Harst, P, and Rienstra, M

Published
2022

48. Surface compressive and softening effect on deformation mode transition in Ni-Nb metallic glassy thin films: A molecular dynamics study.

Author

Chen, L. Y., Cao, Q. P., Zhang, H., Wang, X. D., Zhang, D. X., and Jiang, J. Z.

Subjects
*MOLECULAR dynamics, *METALLIC glasses, *SURFACES (Technology), *DEFORMATIONS (Mechanics), *NICKEL, *NIOBIUM
Abstract

Size-dependent deformation mode transition in metallic glasses (MGs) attracts a lot of interest due to potential application in micro-devices, but the underlying mechanisms are still unclear from the perspective of structure, e.g., how the chemical composition affects the deformation mode transition in a particular system is mysterious as well and needs to be addressed. Here, a series of NixNb100−x (x = 30, 50, 62, and 70 at. %) MG thin films has been studied by molecular dynamics simulations for better understanding the thickness-dependent tensile behaviors. The results show that the deformation mode transition from highly-localized to non-localized occurs as the film thickness (t) approaches the critical size, tc, which strongly correlates with the chemical composition, i.e., a Ni-rich specimen with higher modulus has smaller tc. It is revealed that the softening and compressive effect of surface layers with about 0.4 nm thickness in terms of Voronoi volume is the key factor for this transition regardless of composition. We illustrate the surface softening effect in various MG thin films by introducing a softening coefficient (Ψ) parameter reflecting the structural difference between the surface layer and the internal part. It is found that the higher the Ψ, the severer the surface softening effect, and the larger the tc in the Ni-depleted specimen, indicating the importance of Ψ as an indicator for the deformation mode transition. [ABSTRACT FROM AUTHOR]

Published
2018
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