Mold surface temperature strongly influences the molecular orientation and morphology developed in injection molded samples. In this work, an isotactic polypropylene was injected into a rectangular mold, in which the cavity surface temperature was properly modulated during the process by an electrical heating device. The induced thermo-mechanical histories strongly influenced the morphology developed in the injection molded parts. Polarized optical microscope and atomic force microscope were adopted for morphological investigations. The combination of flow field and cooling rate experienced by the polymer determined the hierarchical structure. Under strong flow fields and high temperatures, a tightly packed structure, called shish-kebab, aligned along the flow direction, was observed. Under weak flow fields, the formation of β-phase, as cylindrites form, was observed. The formation of each morphological structure was analyzed and discussed on the bases of the flow and temperature fields, experienced by the polymer during each stage of the injection molding process.
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http://dx.doi.org/10.3390/ma12030424 | DOI Listing |
Tissue Eng Regen Med
January 2025
College of Materials Science and Engineering, Hunan University, Changsha, 410072, People's Republic of China.
Background: Tissue engineering holds promise for vascular repair and regeneration by mimicking the extracellular matrix of blood vessels. However, achieving a functional and thick vascular wall with aligned fiber architecture by electrospinning remains a significant challenge.
Methods: A novel electrospinning setup was developed that utilizes an auxiliary electrode and a spring.
Behav Res Methods
January 2025
Department of Cognitive Sciences, University of California, 92697, Irvine, CA, USA.
It is popular to study individual differences in cognition with experimental tasks, and the main goal of such approaches is to analyze the pattern of correlations across a battery of tasks and measures. One difficulty is that experimental tasks are often low in reliability as effects are small relative to trial-by-trial variability. Consequently, it remains difficult to accurately estimate correlations.
View Article and Find Full Text PDFSci Rep
January 2025
School of Electronics and Information, Xijing University, Xi'an, 710123, China.
To enhance high-frequency perceptual information and texture details in remote sensing images and address the challenges of super-resolution reconstruction algorithms during training, particularly the issue of missing details, this paper proposes an improved remote sensing image super-resolution reconstruction model. The generator network of the model employs multi-scale convolutional kernels to extract image features and utilizes a multi-head self-attention mechanism to dynamically fuse these features, significantly improving the ability to capture both fine details and global information in remote sensing images. Additionally, the model introduces a multi-stage Hybrid Transformer structure, which processes features at different resolutions progressively, from low resolution to high resolution, substantially enhancing reconstruction quality and detail recovery.
View Article and Find Full Text PDFSci Rep
January 2025
International Livestock Research Institute (ILRI), Human and Animal Health, Berlin, Germany.
Crimean Congo hemorrhagic fever (CCHF) is a re-emerging tick-borne zoonosis that is caused by CCHF virus (CCHFV). The geographical distribution of the disease and factors that influence its occurrence are poorly known. We analysed historical records on its outbreaks in various countries across the sub-Saharan Africa (SSA) to identify hotspots and determine socioecological and demographicfactors associated with these outbreaks.
View Article and Find Full Text PDFInt Nurs Rev
March 2025
Department of Foreign Languages, Fooyin University, Kaohsiung City, Taiwan.
Aim: This study explored the relationship between workplace bullying, authentic leadership, workplace friendship and nurses' health conditions and identified the predictors of nurses' health. It also explored whether authentic leadership moderated the impact of workplace bullying on their health.
Methods: This study used a cross-sectional and correlational design following the STROBE guidelines.
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