Introduction to multifunctional polymer nanocomposites

The nano era, similar to the mid-industrial steel era, not only stands for great technical innovations but also indicates the future trend of existing technologies. It is believed that this period will dominate and transform people's daily lives. 'Nano' is a unit of length defined as 10-9 m. To give you an idea of how small it is, the width of a human hair is 10-6 nm, and the size of an atom is 0.1 nm. In recent decades, the development of microscopes has enabled scientists to observe the structures of the materials at nanoscale and investigate their novel properties. In the early 1980s, IBM (Zurich) invented the scanning tunneling microscope, which was the first instrument that could 'see' atoms. In order to expand the types of materials that could be studied, scientists invented the atomic force microscope. Now, these instruments can be used to observe the structures and different properties of materials at nanometer scale. Physics reveals big differences at the nanometer scale, and the properties observed on a microscopic scale are novel and important. For example, quantum mechanical and thermodynamic properties have pushed forward the development of science and technology in the 20th century. Nanotechnology means the study and application of materials with structures between 1 and 100 nfn in size. Unlike bulk materials, one can work with individual atoms and molecules and learn about an individual molecule's properties. Also, we can arrange atoms and molecules together in well-defined ways to produce new materials with amazing characteristics. For example, nanotechnology has produced huge increases in computer speed and storage capacity. That is why 'nano' has attracted attention in the research fields of physics, chemistry, biology, and even engineering. This word has entered the popular culture and can be found in television, movie, and commercial advertisements. Politicians and leaders around the world have realized the importance and urgency of developing nanoscience and nanotechnology, so countries have promoted research in nanoscience and nanotechnology in their universities and laboratories. With the huge increase in funding, scientists are pursuing nano research intensively, and the rate of discovery is increasing dramatically

A clinicopathological study of non-functioning pituitary neuroendocrine tumours using the World Health Organization 2022 classification

BackgroundThe 2022 World Health Organization (WHO) classification of pituitary neuroendocrine tumour (PitNET) supersedes the previous one in 2017 and further consolidates the role of transcription factors (TF) in the diagnosis of PitNET. Here, we investigated the clinical utility of the 2022 WHO classification, as compared to that of 2017, in a cohort of patients with non-functioning PitNET (NF-PitNET).MethodsA total of 113 NF-PitNET patients who underwent resection between 2010 and 2021, and had follow-up at Queen Mary Hospital, Hong Kong, were recruited. Surgical specimens were re-stained for the three TF: steroidogenic factor (SF-1), T-box family member TBX19 (TPIT) and POU class 1 homeobox 1 (Pit-1). The associations of different NF-PitNET subtypes with tumour-related outcomes were evaluated by logistic and Cox regression analyses.ResultsBased on the 2022 WHO classification, the majority of NF-PitNET was SF-1-lineage tumours (58.4%), followed by TPIT-lineage tumours (18.6%), tumours with no distinct lineage (16.8%) and Pit-1-lineage tumours (6.2%). Despite fewer entities than the 2017 classification, significant differences in disease-free survival were present amongst these four subtypes (Log-rank test p=0.003), specifically between SF-1-lineage PitNET and PitNET without distinct lineage (Log-rank test p<0.001). In multivariable Cox regression analysis, the subtype of PitNET without distinct lineage (HR 3.02, 95% CI 1.28-7.16, p=0.012), together with tumour volume (HR 1.04, 95% CI 1.01-1.07, p=0.017), were independent predictors of a composite of residual or recurrent disease.ConclusionThe 2022 WHO classification of PitNET is a clinically useful TF and lineage-based system for subtyping NF-PitNET with different tumour behaviour and prognosis

Carbon nanotube-reinforced nanocomposites

A single-walled nanotube (SWNT), similar to a sheet of graphene, rolls over to form a tube with the longest ends joined together to form a cylinder, and theoretically possesses superior mechanical, electrical, and thermal properties. In this regard, graphene has been referred to as an infinite alternant (only a six-member carbon ring). Mechanical property tests showed that graphene has a breaking strength 200 times greater than steel. However, the process of separating it from graphite, where it occurs naturally, will require some technological developments before it becomes economical enough to be used in industrial processes

Novel phenolic resins with improved mechanical and toughness properties

Novel phenolic type of thermoset resins were synthesized, and their mechanical and toughness properties were evaluated. Phenol Formaldehyde (PF) phenolic resins were modified to broaden their applications for modern composite structures. A first modification consisted of copolymerization of Phenol with Cardanol during the synthesis of resole phenolic (CPF) resins. The modified phenolic resins (CPF) were prepared at various molar ratios of total Phenol to Formaldehyde (F : P ratio) and with different weight ratios of Phenol to Cardanol. CPF resins with a maximum content of 40 wt % of Cardanol were synthesized and used. The CPF resins were applied as a plasticizer and toughening agent to the base PF resins. Both resins (CPF/PF) were mixed in different proportions, and their thermal and mechanical properties were then established. A full miscibility of the two resins was observed with the formation of a single-phase system. An increase in the content of Cardanol resulted in a propor- tional increase of the flexural strength and fracture tough- ness together with a decrease of the flexural modulus of the cured CPF/PF resins. Further increased plasticizing and toughening effect was also observed by the blending of the CPF resins with propylene glycol. The higher tough- ness and flexibility effect of the CPF resins was obtained with a F : P molar ratio equal to 1.25 and with a Cardanol content of 40% (w/w)

Experimental investigation on the interfacial adhesion of date palm fibres with epoxy matrix

Interfacial adhesion of natural fibres as reinforcement is the key parameter to be considered in fibre polymeric composites. In the current work, interfacial adhesion of date palm fibre is inverstigated using single fibre pull out experiments. The interfacial property of date pal fibre was determined with epoxy matrix. Scanning Electron Microscopy (SEM) was used to examine the surface morphology and damage feature on the fibre before and after the test. The influence NaOH treatment at different concentrations (0% - 9%) and embedded fibre length in the epoxy matric are considered. The results revealed that treated the fibre with 6% NaOH highly enhanced interfacial adhesion of the date palm fibre with epoxy matrix. The embedded length of the fibre controlled the interfacial adhesion property of the fibre where 15mm embedded length was the optimum fibre length. The lowest fibre critical length can be obtained at lower fibre diameter and 6% NaOH treatment