المؤلفون: Yue, Lei, Lu, Ziyou, Yan, Kun, Wang, Le, Guo, Shu, Guo, Ruixin, Chen, Peng, Chen, Xiaobin, Mei, Jia-Wei

مصطلحات موضوعية: Condensed Matter - Strongly Correlated Electrons

الوصف: In our study, we conduct magnetization and heat capacity measurements to investigate field induced magnetic phase transitions within the newly synthesized compound K2Ni2(SeO3)3, a spin-1 dimer system arranged on a triangular lattice. From our first-principles simulations, we determine that the spin system in K2Ni2(SeO3)3 can be represented as a two-dimensional triangular-lattice spin-1 dimer model, including an intra-dimer exchange of J1 = 0.32 meV, an inter-dimer exchange of J2 = 0.79 meV, and an easy-axis anisotropy of D = 0.14 meV. The presence of easy-axis magnetic anisotropy explains the distinct magnetic phase diagrams observed under c-axis directional and in-plane magnetic fields. Notably, our investigation unveils a two-step phase transition with the magnetic field aligned with the c direction. Our findings yield valuable insights into the magnetic phase transitions inherent to geometrically frustrated magnetic systems featuring dimer structures.
Comment: 11 pages, 11 figures

الوصول الحر: http://arxiv.org/abs/2309.10335Test

المؤلفون: Fütterer, Tim, Fischer, Christian, Alekseeva, Anastasiia, Chen, Xiaobin, Tate, Tamara, Warschauer, Mark, Gerjets, Peter

المصدر: Scientific Reports. 13(1)

الوصف: The release and rapid diffusion of ChatGPT have caught the attention of educators worldwide. Some educators are enthusiastic about its potential to support learning. Others are concerned about how it might circumvent learning opportunities or contribute to misinformation. To better understand reactions about ChatGPT concerning education, we analyzed Twitter data (16,830,997 tweets from 5,541,457 users). Based on topic modeling and sentiment analysis, we provide an overview of global perceptions and reactions to ChatGPT regarding education. ChatGPT triggered a massive response on Twitter, with education being the most tweeted content topic. Topics ranged from specific (e.g., cheating) to broad (e.g., opportunities), which were discussed with mixed sentiment. We traced that authority decisions may influence public opinions. We discussed that the average reaction on Twitter (e.g., using ChatGPT to cheat in exams) differs from discussions in which education and teaching-learning researchers are likely to be more interested (e.g., ChatGPT as an intelligent learning partner). This study provides insights into peoples reactions when new groundbreaking technology is released and implications for scientific and policy communication in rapidly changing circumstances.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/8r23r816Test

المؤلفون: Mei, Jia-Wei, Ye, Fei, Chen, Xiaobin

مصطلحات موضوعية: Condensed Matter - Strongly Correlated Electrons

الوصف: The charge-density-wave (CDW) order with macroscopically occupied electrons distorts the underlying lattice and usually causes the softening of the associated phonon mode. However, previous studies demonstrated that the spin-Peierls transition does not always induce an associated phonon softening, but the central-peak scenario applied in the quasi-one-dimensional compound CuGeO$_3$. We generalize the lattice-dynamics studies on the two-dimensional CDW state at van-Hove-singularity (VHS) filling and find that the CDW ordering could develop a central peak at zero frequency while the associated phonon undergoes hardening. The particle-hole scatterings between VHS points give rise to a low-energy increased charge-density susceptibility, and their coupling to the lattice dynamics induces two poles in the Green function for the CDW-associated phonon mode. The zero-frequency pole corresponds to the collective charge-density and phonon coupling mode. The high-frequency one is related to the high-temperature phonon mode that hardens as reaching the CDW transition. Our result may have the potential implication for the recently discovered Kagome metal $A$V$_3$Sb$_5$ ($A$ = K, Rb, Cs) in which no soft phonon is observed during the CDW transition.

الوصول الحر: http://arxiv.org/abs/2204.05216Test

المؤلفون: Chen, Xiaobin, Wang, Guonian

المصدر: Advances in Social Science, Education and Humanities Research ; Proceedings of the 2024 3rd International Conference on Social Sciences and Humanities and Arts (SSHA 2024) ; page 15-22 ; ISSN 2731-8060 2352-5398 ; ISBN 9782384762583 9782384762590

الإتاحة: https://doi.org/10.2991/978-2-38476-259-0_3Test

المؤلفون: Cheng, Li, Long, Xuanyu, Chen, Xiaobin, Zou, Xiaolong, Liu, Zheng

المصدر: Phys. Rev. B 104, L241114 (2021)

مصطلحات موضوعية: Condensed Matter - Materials Science

الوصف: Electronic flat bands serve as a unique platform to achieve strongly-correlated phases. The emergence of a flat band around the Fermi level in 1T-TaS$_2$ in accompany with the development of a $\sqrt{13}\times\sqrt{13}$ charge density wave (CDW) superlattice has long been noticed experimentally, but a transparent theoretical understanding remains elusive. We show that without CDW, the primary feature of the $1\times1$ bands can be fitted by a simple trigonometric function, and physically understood by choosing a rotated $\tilde{t}_{2g}$ basis with the principle axes aligning to the tilted TaS$_6$ octahedron. Using this basis, we trace the band evolution in the $\sqrt{13}\times\sqrt{13}$ superlattice by progressively including different CDW effects. We point out that CDW strongly rehybridizes the three $\tilde{t}_{2g}$ orbitals, which leads to the formation of a well-localized molecular orbital and spawns the flat band.

الوصول الحر: http://arxiv.org/abs/2109.05672Test

المؤلفون: Isbell, Daniel R., Kim, Kathy MinHye, Chen, Xiaobin

الوصف: Published version

وصف الملف: p. 100076

العلاقة: Research Methods in Applied Linguistics; http://dx.doi.org/10.1016/j.rmal.2023.100076Test; D.R. Isbell, K.M. Kim, X. Chen. 2023. "Exploring the potential of automated speech recognition for scoring the Korean Elicited Imitation Test" Research Methods in Applied Linguistics, Volume 2, Issue 3, pp.100076-100076. https://doi.org/10.1016/j.rmal.2023.100076Test; https://hdl.handle.net/2144/48424Test; 0000-0001-5850-8809 (Isbell, Daniel R); 0000-0001-6794-3546 (Kim, Kathy MinHye); 883988

الإتاحة: https://doi.org/10.1016/j.rmal.2023.100076Test
https://hdl.handle.net/2144/48424Test

المؤلفون: Xiao, Ben, Lu, Meng, Chen, Xiaobin, Qiu, Daojing, He, Yuanming, Li, Xuejun

المصدر: International Wound Journal ; volume 21, issue 4 ; ISSN 1742-4801 1742-481X

الوصف: Wound complications after surgery for ankle fractures can lead to catastrophic consequences. The purpose of this study was to evaluate the risk factors of postoperative wound complications in patients with ankle fracture and to determine their effects on prognosis. 200 patients with ankle fracture treated in our hospital from October 2021 to December 2023 were analysed retrospectively. The total incidence of postoperative wound complications was 19% (38/200). Type of complications: wound edge necrosis 15 cases (39.47%), dehiscence (reopening of wound) 13 cases (34.21%), delayed healing (>30 days) 10 cases (26.32%); Univariate analysis showed that patients' age, body mass index (BMI), current smoking, alcoholism, diabetes mellitus, injury mechanism, open fracture, wound classification, higher American Society of Anesthesiologists (ASA) score and operation time were all associated with postoperative wound complications. Multivariate Logistic regression model shows: age ≥60 years old OR3.671 (1.875–5.937), BMI OR1.198 (1.143–1.324), current smoking OR2.727 (1.251–5.602), alcoholism OR1.143 (1.034–1.267), complicated with diabetes OR2.763 (1.236–4.852), injury mechanism (high vs. low and medium energy) OR2.437 (1.238–4.786), open fracture OR1.943 (1.8262.139), wound classification (II vs. I) OR4.423 (1.73511.674), ASA score (III–IV vs. I–II) OR1.307 (1.113–2.194) was an independent risk factor for postoperative wound complications in patients with ankle fracture. Further, ROC curves showed that these nine independent influences had high accuracy and validity in predicting postoperative wound complications in patients with ankle fractures. In conclusion, independent risk factors for postoperative complications of ankle fracture were age >60 years, BMI, injury mechanism, open fracture, wound classification (II vs. I), ASA score, current smoking, and alcoholism. The wound classification (II vs. I) has the highest diagnostic value.

الإتاحة: https://doi.org/10.1111/iwj.14845Test

المؤلفون: Xiong, Qiumin, Chen, Xiaobin, Qiu, Nianli, Xu, Meizhou, Yang, Xianxian

المصدر: Journal of Physics: Conference Series ; volume 2713, issue 1, page 012008 ; ISSN 1742-6588 1742-6596

الوصف: Anti-mud polycarboxylic acid slump retaining agent was prepared by copolymerization of ethylene glycol monovinyl polyethylene glycol ether, diethyl 4-vinylphenyl phosphate, 2-methyl-2-(4-vinylphenyl) propionic acid, unsaturated carboxylic acid (or unsaturated carboxylic anhydride) and unsaturated carboxylic ester under the action of initiator and molecular weight regulator. The effect of the slump retaining agent on the workability of fine aggregate concrete with different mud contents was tested, and the sensitivity of the slump retaining agent to the mud content of machine-made sand was evaluated. At the same time, the viscosity reduction performance of the slump retaining agent was evaluated by using the emptying time of the inverted slump cone and the flow time of V-funnel and L-box. The experimental results show that the synthesized anti-mud polycarboxylic acid slump retaining agent has favourable effects of anti-mud and viscosity reduction.

الإتاحة: https://doi.org/10.1088/1742-6596/2713/1/012008Test

المؤلفون: Chen, Xiaobin, Zhang, Zhongliang, Shu, Lin, Tao, Xiaoming, Xu, Xiangmin

المساهمون: Innovation and Technology Commission

المصدر: Sensors and Actuators A: Physical ; volume 370, page 115208 ; ISSN 0924-4247

مصطلحات موضوعية: Electrical and Electronic Engineering, Metals and Alloys, Surfaces, Coatings and Films, Condensed Matter Physics, Instrumentation, Electronic, Optical and Magnetic Materials

الإتاحة: https://doi.org/10.1016/j.sna.2024.115208Test
https://api.elsevier.com/content/article/PII:S0924424724002012?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S0924424724002012?httpAccept=text/plainTest

المؤلفون: Kim, Kathy Minhye, Liu, Xiaoyi, Isbell, Daniel R., Chen, Xiaobin

المساهمون: Division of Behavioral and Cognitive Sciences

المصدر: Studies in Second Language Acquisition ; page 1-22 ; ISSN 0272-2631 1470-1545

الوصف: Elicited imitation (EI) tasks are a practical tool for measuring second language (L2) knowledge and skills. In this study, we implemented a web-based EI task that measures English morphosyntactic knowledge and compared its measurement properties to a traditional laboratory-based EI. A cohort of 149 L2 English learners engaged in the web-based EI task, and 151 participants completed a traditional lab-based EI counterpart. Correlation analyses revealed a significant, comparable relationship between English proficiency and the two EI versions, with the ungrammatical items showing less consistency that neither improved nor harmed the overall EI effectiveness. Factor analyses corroborated the validity of web-programmed EI, with both EI versions relating similarly to time-pressured, implicit knowledge and untimed, explicit knowledge measures. Our results suggest the potential for utilizing web-based EI to substitute lab-based tasks, enabling larger-scale, more diverse sampling. We end with implications for future web-based EI task users and include a coding guideline for customized web-based EI use.

الإتاحة: https://doi.org/10.1017/s0272263124000214Test
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0272263124000214Test