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Converting plastic waste into valuable resources: a new step in recycling technology
No full textThis work aimed to address the environmental challenge of plastic waste disposal by exploring an innovative recycling technology to convert this PET waste into valuable and efficient resources. This technology has been used to convert polyethylene terephthalate (PET) into nanofibers with unique properties and diverse applications. The study relied on the use of unconventional cutting methods to reduce the waste into small pieces and produce by-products in the form of nanofibers. The analyses were carried out using techniques such as SEM, FTIR, XRD and DSC, in addition to testing the tensile properties and dielectric constant of the resulting nanofibers according to the ASTM D 882 and ASTM D150. The results of SEM analysis showed that the diameters of the nanofibers were between 400 and 600 nm without changing the chemical composition according to the FTIR analysis, while the XRD analysis showed an amorphous structure of the nanofibers. The DSC results also confirmed better thermal stability of these fibers compared to powdered PET, and the nanofibers exhibited the highest tensile strength and lowest dielectric constant. The present study finds that the current new innovative technology for converting polyethylene terephthalate into nanofibers by means of an unconventional cutting process offers an economical and sustainable solution with lower costs and higher efficiency than the conventional methods and has not been studied before. It also improves recycling and nanotechnology, opening up new horizons for innovation
Between a curse and a blessing: Germany's role in shaping the EU-Turkish relations with the Eastern Mediterranean as a litmus test
No full textGermany substantially influenced Türkiye’s relations with the European Union as a preponderant player in European politics. With accession negotiations de facto frozen, the EU refers to Türkiye as a key partner, but also as a challenger in the Eastern Mediterranean. The EU’s highly complex internal dynamics with member states’ diverging interests complicate Türkiye’s relations with the EU. The Eastern Mediterranean has become a hotspot for regional rivalry with ongoing power struggles between Türkiye, Greece, and Cyprus over sovereign rights. While the EU has sided with its member states in this conflict, entangling the multiple knots that involve these three Mediterranean countries–two of whom are EU members–and preserving peace in this region has become a top priority for Germany. This paper’s focus on the Eastern Mediterranean knot is based on the theoretical insights from liberal intergovernmentalism, with Germany’s relative power shaping European foreign policy towards Türkiye. The paper utilises legal, official documents from Germany and the EU to perform a co-occurrence network analysis, to combine empirical analysis with this theoretical background. The aim is to investigate the extent to which Germany, as an autonomous actor, influenced European foreign policy towards Türkiye and the Eastern Mediterranean
Production of collagen modified PDLA biofilms
No full textEnhancing the biological functionality of polymeric biomaterials, particularly cell adhesion, proliferation, and biocompatibility, is essential for developing functional applications in tissue engineering. In this work, poly(D-lactic acid) (PDLA) was covalently grafted with collagen (PDLA-g-Coll) to overcome PDLA's inherent limitations in cellular interactions. The hybrid films were fabricated via solvent casting and subjected to comprehensive biological evaluation. In vitro experiments using L929 mouse fibroblast cells, demonstrated a marked enhancement in cell attachment and proliferation on the PDLA-g-Coll films compared to unmodified PDLA and pure collagen controls, as confirmed by MTT assays. These improvements are attributed to the increased surface hydrophilicity conferred by the grafted collagen chains, a finding corroborated by contact angle measurements. The favorable surface morphology of the PDLA-g-Coll films further supported cell proliferation. Collectively, these results highlight the synergistic integration of PDLA's mechanical strength and biodegradability with collagen's bioactivity, yielding a composite material with significant potential for application in tissue engineering
Rubber-based nanoblends
No full textRecently, rubber materials mixed with tiny, nanoscale fillers have really taken off in many fields. This chapter looks at several common rubbers—natural rubber, SBR, EPDM, NBR, and silicone rubber—and shows how adding things like graphene, carbon nanotubes, or metal-oxide particles can bump up properties such as strength, conductivity, and heat resistance. We talk through practical challenges too, for example, how hard it is to get those fillers to spread evenly. Then we move on to real-world uses: from car parts and vibration dampers to flexible circuits, energy storage devices, and EMI shielding panels. Sustainability comes up as well, because today’s research needs to think about both performance and the planet. All in all, rubber nanocomposites are set to play an even bigger role, especially as we push for greener, smarter materials
Individual differences in object imagery, spatial imagery, verbal skills, and personality in relation to centrality of positive and negative events
No full textEvent centrality refers to the extent to which an individual integrates a meaningful life event into their identity. This study examined how different types of imagery, verbal skills, personality traits, and sex predict the centrality of autobiographical events. Object imagery and verbal skills predicted the centrality of positive autobiographical events, indicating that both vivid representations and narrative construction of memories are crucial for their integration into one's self-concept. However, neither imagery nor verbal skills predicted the centrality of negative events. Sex predicted negative event centrality, with females reporting higher centrality than males. Neuroticism appeared to play a critical role in the integration of negative experiences into one's self-concept, overshadowing the direct effects of sex. Conscientiousness positively predicted the centrality of positive memories and negatively predicted the centrality of negative memories. Our findings contribute to understanding how different facets of individual differences collectively shape the centrality of positive and negative events
Terahertz emission from intrinsic Josephson junctions in trilayer cuprate superconductor Bi2Sr2Ca2Cu3O10+δ
No full textThis study presents the first observation of a continuous electromagnetic terahertz wave emission from mesoscopic mesas of the trilayer high- T c superconductor, Bi2Sr2Ca2Cu3O10+δ (Bi-2223), a putative Josephson plasma emitter utilizing intrinsic Josephson junctions. Two types of Bi-2223 crystals, optimally doped and underdoped, were prepared via thermal annealing under controlled partial oxygen pressures, and their electrical and emission characteristics were compared. A weak, but detectable terahertz emission was observed from the underdoped Bi-2223 mesas, whereas no radiation was observed from the optimally doped ones. We associate the low terahertz emission output with the weak capacitive coupling between the intrinsic junctions in the trilayer system
Türk edebiyatı 101: Orhun Yazıtları'ndan divan edebiyatına, Nazım Hikmet'ten Tutunamayanlar'a Türk edebiyatı hakkında bilmeniz gereken her şey
No full textTürk Edebiyatıyla İlgili Merak Ettiğiniz Her Şey Bu Kitapta!
Türk edebiyatı, hem sözlü hem de yazılı geleneğin en zengin örneklerini barındıran, köklü bir geçmişe sahip bir birikimdir. Orta Asya Türklerinin sözlü ve yazılı edebiyat ürünlerinden 20. yüzyılın sonlarındaki postmodern romanlara kadar uzanan geniş bir yelpazede, Türk edebiyatına dair bilmeniz gereken her şey, rehber niteliğindeki bu kitapta bir araya getiriliyor.
Sade ve akıcı anlatımıyla Türk Edebiyatı 101, İslamiyet öncesi Türk edebiyatı, divan edebiyatı, halk edebiyatı, Batılılaşma etkisindeki edebiyat, Erken Cumhuriyet Dönemi ve sonrasındaki edebi yaklaşımlar hakkında temel bir kavrayış sunuyor. Ders kitaplarındaki sıkıcı ve tekdüze anlatımların aksine, toplumsal ve kültürel gelişmeler hakkındaki ilginç bilgiler ve görsellerle zenginleştirilmiş içeriğiyle Türk edebiyatının eserlerini, yazarlarını ve şairlerini tanımayı çok daha kolay hale getiriyor
A 24-to 28-GHz 4x1 MIMO transmitter/receiver for 5G phased-array applications with high amplitude and phase control
No full textThis paper introduces a 4-channel 24- to 28-GHz RF front-end MIMO system designed for 5G applications. The transmitter (Tx) and receiver (Rx) chips are fabricated using 130-nm SiGe BiCMOS technology. The chips contain a 6-bit phase shifter (PS), 1-bit attenuator (ATT), 3-bit variable gain amplifier (VGA), serial peripheral interface (SPI), Wilkinson combiner, power amplifier (PA), and low noise amplifier (LNA). The designed vector-sum PS, employing a current DAC for semi-digitization, achieves a 6-bit phase resolution with minimal root-mean-square (RMS) phase error. This design choice allows for the high bit control of the current DAC within a compact chip area. Four-bit amplitude control is obtained with VGA and ATT. The VGA provides 8-dB amplitude range while ATT enlarges overall amplitude control with additional 8 dB. L-R-L phase compensation technique is utilized to reduce the phase error that arises from ATT. The sub-blocks are designed to operate with low DC power such that the DC power consumption of overall RX and TX is 50 and 97 mW, respectively. The measurement results of a single-channel indicate a gain of 15.5-dB and −25-dBm IP1dB for the RX chip and 26.5-dB and 10-dBm OP1dB for the TX chip while each chip occupies 0.83 mm (Formula presented.). The RX chip exhibits a measured noise figure (NF) of 4.3 dB at 26 GHz. Both Tx and Rx chips achieve 6-bit phase control and 4-bit amplitude control with low RMS phase error of 2.6° and gain error of 0.3 dB. Low RMS gain and phase errors over a wide bandwidth are attributed to the high precision DAC employed in the control of VGA and PS. Both chips are flip-chip packaged and undergo upconversion/downconversion via external mixers on a printed circuit board (PCB). System-level tests with 64-quadrature amplitude modulation (QAM) show an error vector magnitude (EVM) of 2.72% at 27 GHz for RX and 5.02% at 24 GHz for TX, with a 50-MBaud modulated signal applied at a data rate of 300 MBps
The effects of PLGA nanoparticles containing different growth factors on neural stem cell differentiation and their transition efficiency after targeting with TRF
Get PDFAims: Nanoparticle-mediated drug delivery systems are being investigated for the controlled release of drugs to treat neurodegenerative diseases (ND). We aimed to investigate the effects of poly(lactic-co-glycolic acid) nanoparticles (PLGA-NPs) containing different growth factors (GFs) on rat brain-derived neural stem cells (NSCs) in vitro differentiation, providing insights that may contribute to future approaches for treating Parkinson's disease. Methods: Three different PLGA-NPs loaded with Brain-Derived Neurotrophic Factor (BDNF), Glial-Derived Neurotrophic Factor (GDNF), and Transforming Growth Factor beta 3 (TGF-β3) were developed and characterized in terms of size, zeta potential, encapsulation efficiency, and release profile. These NPs were used to differentiate NSCs into dopaminergic neurons in vitro. Additionally, the transition of transferrin (TRF)-conjugated PLGA-COOH-NPs across an in vitro blood–brain barrier (BBB) model was investigated. Results: The average sizes of BDNF, GDNF, and TGF-ß3 loaded PLGA-NPs were measured to be 217.17 ± 1.37, 227.37 ± 5.39, and 220.57 ± 10.10 nm, respectively. Besides, SEM imaging revealed that the particles had a homogeneous size distribution and smooth surface morphology. Microtubule-associated protein 2 (Map2) and tyrosine hydroxylase (TH), two dopaminergic neuronal markers, were found in cells with neuron-like morphology that were produced through in vitro differentiation. The cellular uptake of PLGA-NPs loaded with Coumarin-6 was determined by using confocal imaging and flow cytometry. It was demonstrated that TRF-conjugated NPs were specifically targeted and taken up into NSCs in the in vitro BBB model. Conclusion: It is concluded that BDNF-PLGA-NPs, GDNF-PLGA-NPs, and TGF-ß3-PLGA-NPs are promising brain drug delivery carriers for NSC inducers, which could be useful in developing strategies for Parkinson's disease management, particularly when targeted with TRF
The first hydrogen valley of Turkey: The HYSouthMarmara Project
No full textThe HYSouthMarmara project aims to establish a large-scale green hydrogen production and utilization ecosystem in the South Marmara region of Turkey. The initiative focuses on leveraging the region’s abundant renewable energy resources, particularly wind and solar power, to produce hydrogen via electrolysis, thereby contributing to Turkey’s decarbonization targets and energy transition efforts. The project envisions the development of a 4 MW electrolyser capacity to establish an integrated hydrogen value chain, involving collaboration among multiple stakeholders, including energy producers, industrial consumers, policymakers, and research institutions. The implementation of HYSouthMarmara will involve a phased approach, with initial pilot projects followed by large-scale deployment. Key challenges include infrastructure development, policy support, and market readiness, which will be addressed through public-private partnerships and international cooperation. In conclusion, HYSouthMarmara represents a significant step toward a sustainable hydrogen economy in Turkey. By capitalizing on renewable energy potential and fostering technological innovation, the project aims to accelerate the adoption of green hydrogen and support global efforts to combat climate change