Publications by authors named "Lichun Bai"

Introduction: Necrotising enterocolitis (NEC) of the intestine of preterm infants leads to the risk of abdominal surgery, short bowel syndrome, neurodevelopmental disorders and death. Although the risks of NEC and its complications have been recognised in many countries, few countries have established NEC-specific registries to continuously monitor its aetiology and prognosis. In China, the understanding of risk factors and prognosis of NEC is incomplete, characterised by a lack of evidence from prospective and multicentre studies.

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Study on the dynamic process of CL-20 crystal under impact is critical for the safe utilization of energetic materials under extreme conditions. Herein, the mechanical and structural evolution of CL-20 under the impact of a diamond ball is investigated by using molecular dynamics simulation. The considerations are given to the effect of different impact velocity, impact direction and impact angle.

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The separation behavior of a variety of emerging contaminants, including nine antibiotics and six estrogens commonly reported in natural environment, by four commercial nanofiltration and reverse osmosis (NF/RO) membranes at various water conditions (pH, concentration) was investigated. The contaminant rejection at pH 6.0 followed a decreasing trend of XLE (94%-100%) ≈ NF90 (88%-100%) > NF270 (25%-85%) > DL (16%-75%).

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Ionic liquid (IL) combined with graphene additives have garnered extensive attention in the field of high-performance lubricating materials. However, the ambiguous mechanism of graphene influencing the load-carrying and anti-wear capacity of ILs needs further study. In this work, friction simulation shows that adding graphene causes friction coefficient to reduce by up to 88% compared with pure ILs, but lubrication performance is lost due to the destruction of graphene under high stress.

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Diamond-like carbon (DLC) films have broad application potential due to their high hardness, high wear resistance, and self-lubricating properties. However, considering that DLC films are micron-scale, neither finite element methods nor macroscopic experiments can reveal their deformation and failure mechanisms. Here we propose a coarse-grained molecular dynamics (CGMD) approach which expands the capabilities of molecular dynamics simulations to uniaxial tensile behavior of DLC films at a higher scale.

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Fabric-based materials have demonstrated promise for high-performance wearable applications but are currently restricted by their deficient mechanical properties. Here, this work leverages the design freedom offered by additive manufacturing and a novel interlocking pattern to for the first time fabricate a dual-faced chain mail structure consisting of 3D re-entrant unit cells. The flexible structured fabric demonstrates high specific energy absorption and specific strength of up to 1530 J kg and 5900 Nm kg , respectively, together with an excellent recovery ratio of ≈80%, thereby overcoming the strength-recoverability trade-off.

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Liquid crystal elastomers (LCEs) are renowned for their large, reversible, and anisotropic shape change in response to various external stimuli due to their lightly cross-linked polymer networks with an oriented mesogen direction, thus showing great potential for applications in robotics, bio-medics, electronics, optics, and energy. To fully take advantage of the anisotropic stimuli-responsive behaviors of LCEs, it is preferable to achieve a locally controlled mesogen alignment into monodomain orientations. In recent years, the application of 4D printing to LCEs opens new doors for simultaneously programming the mesogen alignment and the 3D geometry, offering more opportunities and higher feasibility for the fabrication of 4D-printed LCE objects with desirable stimuli-responsive properties.

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The aerobic biotreatment process for the dual goals of antibiotic removal and ammonia retainment for the field-return-based treatment of swine wastewater was optimized by adding 2-chloro-6-trichloromethylpyridine (TCMP), commonly used as a nitrogen fertilizer synergist. The results show that the dosage of 5-10 mg/L TCMP daily effectively inhibited nitrification. The COD and tetracycline antibiotics (TCs) in the absence of TCMP was removed by 91% and 76%, and became 87% and 78% with 5 mg/L TCMP and 83% and 70% with 10 mg/L TCMP, respectively.

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This study employs the energy-dissipation method to analyze the tribological behaviors of diamond-like carbon (DLC) films through molecular dynamics simulation. It is found that at small load and sliding velocity, the variation trend of average friction force is only dependent on the number of interface bonds (or contact area). However, at large load and sliding velocity, the friction mechanism is not only related to the number of interface bonds but also related to the presence of the transfer layer.

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There has been tremendous interest in the development of different innovative wear-resistant materials, which can help to reduce energy losses resulted from friction and wear by ≈40% over the next 10-15 years. This paper provides a comprehensive review of the recent progress on designs, properties, and applications of wear-resistant materials, starting with an introduction of various advanced technologies for the fabrication of wear-resistant materials and anti-wear structures with their wear mechanisms. Typical strategies of surface engineering and matrix strengthening for the development of wear-resistant materials are then analyzed, focusing on the development of coatings, surface texturing, surface hardening, architecture, and the exploration of matrix compositions, microstructures, and reinforcements.

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The circular motion of submillimeter-sized bubbles attached to a boundary in an 18.5 kHz ultrasonic field are investigated experimentally by high-speed photography and image analysis. It is found that the vibration of gas bubbles with diameters of 0.

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Double-walled carbon nanotubes (DWCNTs) have received a great deal of attention due to their great potential in the field of superlubricity. However, this superlubricity is susceptible to failure in practical applications due to the introduction of various defects. Here, a novel method based on strain engineering is employed for achieving superlubricity in the DWCNT using molecular dynamics simulations.

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Alloying 2D transition metal dichalcogenides has opened up new opportunities for bandgap engineering and phase control. Developing a simple and scalable synthetic route is therefore essential to explore the full potential of these alloys with tunable optical and electrical properties. Here, the direct synthesis of monolayer WTe S alloys via one-step chemical vapor deposition (CVD) is demonstrated.

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Nano-friction of phosphorene plays a significant role in affecting the controllability and efficiency of applying strain engineering to tune its properties. So far, the friction behavior of phosphorene has not been studied. This work studies the friction of single-layer and bilayer phosphorene on an amorphous silicon substrate by sliding a rigid tip.

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The application of few-layered graphene-derived functional thin films for molecular filtration and separation has recently attracted intensive interests. In practice, the morphology of the nanochannel formed by the graphene (GE) layers is not ideally flat and can be affected by various factors. This work investigates the effect of channel morphology on the water transport behaviors through the GE bilayers via molecular dynamics simulations.

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Tribological mechanisms of diamond-like carbon (DLC) films in a sand-dust environment are commonly unclear due to the complicated three-body abrasion caused by sand particles. This study investigates the three-body abrasion of the DLC film via molecular dynamics simulations. The influence factors such as the load, velocity, shape of the particle and its size are considered.

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