Publications by authors named "Wenshan Duan"

5 Publications

  • Page 1 of 1

Deep potential for a face-centered cubic Cu system at finite temperatures.

Phys Chem Chem Phys 2022 Aug 3;24(30):18361-18369. Epub 2022 Aug 3.

Institute of Modern Physics, Chinese Academy of Science, Lanzhou 730000, China.

The state-of-the-art method generating potential functions used in molecular dynamics is based on machine learning with neural networks, which is critical for molecular dynamics simulation. This method provides an efficient way for fitting multi-variable nonlinear functions, attracting extensive attention in recent years. Generally, the quality of potentials fitted by neural networks is heavily affected by training datasets and the training process and could be ensured by comprehensively verificating the model accuracy. In this study, we obtained the neural network potential of face-centered cubic (FCC) Cu with the most accurate and adequate training datasets from first-principle calculations and the training process performed by Deep Potential Molecular Dynamics (DeePMD). This potential could not only succeed in reproductions of the variety of properties of Cu at 0 K, but also have a good performance at finite temperatures, such as predicting elastic constants and the melting point. Moreover, our potential has a better generalization capacity to predict the grain boundary energy without including extra datasets about grain boundary structures. These results support the applicability of the method under more practical conditions.
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http://dx.doi.org/10.1039/d2cp02758eDOI Listing
August 2022

Bedaquiline and Linezolid improve anti-TB treatment outcome in drug-resistant TB patients with HIV: A systematic review and meta-analysis.

Pharmacol Res 2022 Aug 30;182:106336. Epub 2022 Jun 30.

Clinical and Research Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, No 8 Xitoutiao, Youanmenwai, Feng Tai District, Beijing 100069, China. Electronic address:

Objectives: We aimed to assess the effect of second-line anti-TB treatment and determine which drugs can achieve the greatest clinical benefit for DR-TB-HIV patients by comparing multiple chemotherapy regimens, to provide a basis for evidence-based practice.

Methods: We searched three electronic databases (PubMed, Web of Science and Cochrane) for related English studies published since 2010. A random-effect model was used to estimate the pooled result for the treatment outcomes. Subgroup analysis based on possible factors, such as ART, baseline CD4 T-cell count, treatment regimens, and profiles of drug resistance, was also conducted to assess factors for favorable outcome. Outcomes were treatment success and mortality.

Results: 38 studies, 40 cohorts with 9279 patients were included. The pooled treatment success, mortality, treatment failure, and default rates were 57.5 % (95 % CI 53.1-61.9), 21 % (95 % CI 17.8-24.6), 4.8 % (95 % CI 3.5-6.5), and 10.7 % (95 % CI 8.7-13.1), respectively, in patients with DR-TB and HIV co-infection. Subgroup analysis showed that BDQ and LZD based regimen, and ≥ 2 Group A drugs were associated with a higher treatment success rate. Besides, higher CD4 T-cell count at baseline was also correlated with higher treatment success rate, too.

Conclusions: Suboptimal anti-TB outcomes underlining the need to expand the application of effective drugs and better regimen in high HIV setting. BDQ and LZD based all-oral regimen and early ART could contribute to higher treatment success, particularly among XDR-TB-HIV patients. Given that all included studies were observational, our findings emphasize the need for high-quality studies to further investigate the optimal treatment regimen for DR-TB-HIV.
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http://dx.doi.org/10.1016/j.phrs.2022.106336DOI Listing
August 2022

Retention and diffusion of transmutation H and He atoms in BeTi: first-principles calculations.

RSC Adv 2018 Oct 19;8(62):35735-35743. Epub 2018 Oct 19.

Institute of Modern Physics, Chinese Academy of Sciences Lanzhou 730000 China

The beryllide BeTi is considered to be the most promising candidate material for advanced plasma facing materials in future fusion reactors because of its excellent performance. In this work, first-principles calculations were conducted to gain insight into the retention and diffusion behavior of transmutation H and He atoms in BeTi. The solution energy and migration energy of single impurity H/He atoms were computed to study the behavior of their retention and diffusion. Among seven stable interstitial sites, H atoms preferentially occupy the octahedral interstitial site, , whereas He atoms preferentially occupy the dodecahedral interstitial site, . The solubility of H is much higher than that of He in BeTi. When monovacancy is generated, H atoms preferentially stay in the vicinity of Be1 vacancies, while He atoms tend to reside in the center of Ti vacancies. The migration energy barrier of a single He atom between first near-neighbor sites is 0.35 eV. For H atoms, the migration energy barrier from to is 0.45 eV. The barrier along the paths - - is 0.38 eV. When a Be3 vacancy is introduced as the neighbour of , the migration energy barrier increases to 0.77 eV. These results indicate that vacancies can trap impurity atoms and may act as seeds for bubble formation.
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http://dx.doi.org/10.1039/c8ra06768fDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9087962PMC
October 2018

Synergetic effect of H and He impurities in TiAlC: first principles calculations.

Phys Chem Chem Phys 2018 Jul;20(27):18766-18774

College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730000, China.

First principles calculations have been performed to investigate the synergetic effect of H and He impurities with vacancies in Ti3AlC2. The configurations and energetics of Hn-He-VAl complexes (n ≤ 4) and He-He/He-H/H-H interactions have been studied. It is found that the impurity H atom prefers to occupy the tetrahedral interstitial site (Itetr-3), but the He atom prefers to occupy the octahedral interstitial site (Ioct-4) in perfect Ti3AlC2. Within a pre-existing Al vacancy, the most favorable site for a He atom is close to tetr-site, meanwhile the H atom preferentially deviates from the vacancy center with the separation 1.3 Å along the 001 direction. He-H and He-He show a weakly attractive interaction, but weak repulsion occurs in the H-H interaction, which is different from the case of Ti3SiC2. The He-VAl complex plays an important role in the trapping of H atoms. The He-VAl cluster can trap up to three H atoms in the absence of H2 molecules, which leads to the formation of a H-He hybridized bubble. Thus, the He atom can subsequently suppress further aggregation of H atoms and block hydrogen embrittlement and volume swelling.
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http://dx.doi.org/10.1039/c8cp02082eDOI Listing
July 2018

Preliminary research on flow rate and free surface of the accelerator driven subcritical system gravity-driven dense granular-flow target.

PLoS One 2017 2;12(11):e0187435. Epub 2017 Nov 2.

Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China.

A spallation target is one of the three core parts of the accelerator driven subcritical system (ADS), which has already been investigated for decades. Recently, a gravity-driven Dense Granular-flow Target (DGT) is proposed, which consists of a cylindrical hopper and an internal coaxial cylindrical beam pipe. The research on the flow rate and free surface are important for the design of the target whether in Heavy Liquid Metal (HLM) targets or the DGT. In this paper, the relations of flow rate and the geometry of the DGT are investigated. Simulations based on the discrete element method (DEM) implementing on Graphics Processing Units (GPUs) and experiments are both performed. It is found that the existence of an internal pipe doesn't influence the flow rate when the distance from the bottom of the pipe to orifice is large enough even in a larger system. Meanwhile, snapshots of the free surface formed just below the beam pipe are given. It is observed that the free surface is stable over time. The entire research is meaningful for the design of DGT.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0187435PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5667801PMC
December 2017
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