Issue 5


Artificial intelligence and machine learning empowering the mass medicine

Ashutosh Tiwari

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 302-302
DOI: 10.5185/amlett.2019.1005

Today, the world is witnessing great advances in the healthcare industry through technological innovations that will lead to a brighter future. Technology and Innovation is playing a major role in clinical training, robotics, drug discovery, disease management and e-medicine field. Recent advent of Artificial Intelligence (AI) and Machine Learning (ML) has led to massive developments in the healthcare industry. This advancement has enabled the mining of complex data as it is based on artificial intelligence and machine learning algorithms, that processes language and image recognition which can be done for a controlled study of patients. Advanced technology is also playing a major role in drug safety through efficient drug manufacture. There are innovations with regard to mining medical records, and doing a controlled study, along with risk assessment in real-time systems, leading to a reduction in the cost of medical treatments and promising a healthy future.

Piezo-therapy in cancer: Current research and perspectives

Attilio Marino; Gianni Ciofani

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 303-304
DOI: 10.5185/amlett.2018.2192

In this article, we introduce the innovative nanotechnological approach of remote electric stimulation mediated by ultrasound-sensitive piezoelectric nanoparticles, especially focusing on its exploitation in the nanomedicine field for the “wireless” anticancer electric treatment. The nanoparticle functionalization with specific ligands allows the targeting, imaging, and ultimately the treatment of cancer cells. Piezoelectric stimulation can be performed in remote modality with ultrasound waves by virtue of the direct piezoelectric effect. Chronic piezo-stimulation is able to remarkably decrease cancer cell growth by inducing the cell cycle arrest in G0/G1phase and by affecting the cytoskeleton organization during cell division. The reported results indicate an impressive potential impact of this nanotechnological approach, that will be further tested in future works in synergic combination with chemotherapy treatment.

Magnetic microwires for sensor applications

Arcady Zhukov; Paula Corte-León; Lorena González-Legarreta; Mihail Ipatov; Ahmed Talaat; Juan M. Blanco; Julian Gonzalez; Valentina Zhukova

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 305-311
DOI: 10.5185/amlett.2019.2202

The impact of post-processing on soft magnetic properties and the giant magnetoimpedance (GMI) effect of Fe- and Co-based glass-coated microwires is evaluated. A remarkable improvement of magnetic softness and GMI effect is observed in Fe-rich glass-coated microwires subjected to stress annealing. Frequency dependence of GMI ratio of stress-annealed Fe-rich microwires has been discussed considering frequency dependence of the skin penetration depth, δ, as well as magnetic anisotropy distribution within the metallic nucleus. Annealed and stress-annealed Co-rich microwires present rectangular hysteresis loop and single and fast domain wall propagation. However, Co-based stress-annealed microwires present high magnetoimpedance ratio. Observed stress-induced anisotropy and related changes of magnetic properties are discussed considering internal stresses relaxation and “back-stresses”.

A fundamental study on the mechanistic impact of repeated de- and rehydration of Ca(OH)2 on thermochemical cycling in technical scale

Sandra Afflerbach; Reinhard Trettin

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 312-318
DOI: 10.5185/amlett.2019.2190

A major scientific challenge for carbon neutral, environmental friendly future energy production is the development of renewable energy production to technological readiness. One example are solar thermal power plants. Since their energy generation is intermittent, they demand for a feasible storage solution for which thermochemical reaction systems are considered. The present work subjects the thermochemical reaction system CaO / Ca(OH)2 and its structural-mechanical correlations impacting the powder bulk performance upon thermochemical cycling. On exemplified Ca(OH)2 crystals is shown, that during the first de- and rehydration process, the entire crystal morphology is disintegrated. The underlying mechanism is evaluated by theoretical considerations on the layered structure of Ca(OH)2 and validated by scanning electron microscopy (SEM) on the probed material before and after dehydration as well as after rehydration. The obtained findings are transferred to the technically relevant powdery storage material, where they are capable to explain the phenomenon of agglomeration, which is proven by measurement of secondary particle size distribution over a number of ten thermochemical reaction cycles. From SEM imaging performed on the samples it is found, that agglomerates consist of cohering smaller particles. The inferred insights can help to deduce necessary amendments of reactor design or material modification also for other thermochemical reaction systems.

Fabrication and characterization of nano-bridge Josephson junction based on Fe0.94Te0.45Se0.55 thin film

Jia Lu; Wen Zhang; Zheng Wang; Xiaoming Ma; Shicai Shi; Lei Yan; Hong Ding

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 319-323
DOI: 10.5185/amlett.2019.2270

Nano-bridge Josephson junction has been fabricated with Fe0.94Te0.45Se0.55 (FTS) thin films by using focused ion beam etching (FIB). Electrical properties of the Josephson effects of the nano-bridge have been deeply studied. Current-voltage (I-V) characteristics of the junction exhibit resistively and capacitively shunted junction-like (RCSJ) behaviors. Critical current of the junction is 16.1 mA at 4.2 K. The product of the critical current and normal state resistance (IcRn) is higher than those reported in the literatures. Thermal conductance of the nano-bridge increases with increasing resistance, which suggests that the thermal transfer has been enhanced. Noise equivalent power of the nano-bridge is at the order of magnitude of 10-12 WHz-1/2, which is comparable to that of the NbN bolometer. With these unique electrical characteristics, the FTS based nano-bridge could have various potential applications.

Riboflavin-UVA gelatin crosslinking: Design of a biocompatible and thermo-responsive biomaterial with enhanced mechanical properties for tissue engineering

Juan Manuel Galdopórpora; Claudio Javier Perez; María Victoria Tuttolomondo; Martín Federico Desimone

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 324-328
DOI: 10.5185/amlett.2019.2210

The main objective of this study is to develop an economic, environmentally friendly and malleable biomaterial for tissue engineering applications. Water and glycerol have been used as solvents for the gelatin hydrogel synthesis. This solvent mixture led to a biomaterial with improved thermal properties. Indeed, a 16°C increase in thermal transition temperature was achieved. Furthermore, to enhance mechanical properties, riboflavin was used as a crosslinking agent. Chemical crosslinking step was initiated with UV radiation to obtain riboflavin radical polymerization of gelatin chains, hence, rheological properties of gelatin hydrogel were improved. Thus, Gelatin-UV-Riboflavin hydrogel showed good swelling and increased mechanical properties, obtaining a novel material for drug delivery and medical purposes.

Broadband and fast photodetectors based on multilayer p-MoTe2/n-WS2 heterojunction with graphene electrodes

Wenkai Zhu; Faguang Yan; Xia Wei; Quanshan Lv; Huai Yang; Kaiyou Wang

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 329-333
DOI: 10.5185/amlett.2019.2281

Two-dimensional (2D) atomic crystals, such as graphene, black phosphorus and transition metal dichalcogenides (TMDCs) are attractive for use in optoelectronic devices, due to their unique optical absorption properties and van der Waals (vdWs) force between layers. Heterostructures based on layered semiconductors provide a new platform for broadband high-performance photodetectors. In this work, graphene-MoTe2-WS2-graphene vdWs heterojunctions are fabricated for photodetection. The fundamental electric properties and the band structures of the heterojunctions are investigated and discussed. The devices show a high responsivity (≈ 140 mA W -1 at 825 nm), stable and broadband photodetection from UV to NIR wavelength range (300 - 1350 nm), fast response time of 186 µs and self-driven photodetectors. The scanning photocurrent microscopy maps are also employed to study the mechanism of photocurrent generation in the heterojunction. Our results reveal that the vdWs heterojunctions with graphene electrodes offer a new route to broadband detection, optical communication and energy harvesting applications.

Ionic liquid [BMIM][Cl] immobilized on cellulose fibers from pineapple leaves for desulphurization of fuels

Angélica M. Giorgi Perez; Marisol Fernández Rojas; Luz A. Carreño Díaz

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 334-340
DOI: 10.5185/amlett.2019.2277

Industrial combustion of fuels containing sulfur is responsible for most of the greenhouse gases in the atmosphere. The high impact of fuels is mainly on the content of aromatic S-compounds. These compounds are hard to remove through conventional hydrodesulphurization (HDS) processes because of their refractory properties and high boiling points. In this research, we are reporting the preparation, characterization, and evaluation of a cheap, regenerable and reusable composite based on the ionic liquid 1-butyl-3-methylimidazolium chloride immobilized on a renewable matrix of natural cellulose fibers. Characterization of the composite included FTIR, TGA, SEM, and XDR. The extraction capacity of thiophene and benzothiophene of the synthesized material was evaluated in synthetic mixes in isooctane and monitored by GC-FID. We achieved removal percentages of up to 62% of total sulfur from a model oil with an initial concentration of 458 mg S/L.

Synthesis and role of co-dopants (alkaline earth divalents and halides) on the photoluminescence of Eu2+ doped BaAl2O4 phosphor

V. Ponnusamy; A. Azhagiri; R. Satheesh Kumar; M.T. Jose

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 341-345
DOI: 10.5185/amlett.2019.2218

Pure and Eu 2+ doped BaAl2O4 phosphors have been synthesized by simple solid state reaction technique. Synthesized BaAl2O4 samples were studied using powder X-ray diffraction analysis (XRD), Photoluminescence spectroscopy (PL), Fourier Transform - Infra Red Spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM). Alkaline earth divalent (Sr, Ca, Zn, Mg) and halides (F, Cl, Br, I) were used as co-dopants to enhance the PL properties of BaAl2O4:Eu 2+ phosphor. Significant impact of ionic radii of co-dopants on PL properties of the phosphor is reported.

Metal oxide (V2O5) incorporated fly ash based geopolymer for better sustainable engineering composites

Muhammad Akbar Malik; Manas Sarkar; Moumita Maiti; Shilang Xu

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 346-350
DOI: 10.5185/amlett.2019.2174

During the coal-burning process, fly ash is produced as a by-product and disposal of this vast waste material is becoming challenge in the current environmental scenario. In the present work, metal oxide V2O5 with different weights (3% and 5%) of fly ash was utilized in presence of alkaline activators to lower the mullitization temperature below to 1000  o C for the development of new concrete approaches. The building composites were made by using sintered fly ash and alkaline activators at ambient temperature. The micro structural analysis (XRD, FESEM, EDX) of the composites reveals the formation of needle like nano sized mullite at 1000  o C. The durability and mechanical strengths tests including, compressive strength, flexural strength, split tensile strength, chloride ion permeability, water absorption and ultrasonic pulse velocity were conducted on the composites specimens. The experimental tests confirm the better strength and enhanced durability properties of the newly formed building composites. The study suggested a new methodology to utilize the waste material fly ash with vanadium oxide as an alternative cementitious materials for advanced durable building composites.

Highly efficient storage of solar gains using aluminum foam heat exchangers  

Jaroslav Jerz; František Simančík; Peter Tobolka

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 351-354
DOI: 10.5185/amlett.2019.2227

The energy efficiency of buildings is today mostly improved by upgrading the energy performance of the building envelope and facilities. However, huge energy reductions can also be achieved by a focus on the novel systems enabling to cover natural energy fall-outs resulting from generation much excess heat during the peak time (summer, day) which is currently almost not possible to use during periods of excessive energy consumption (winter, night). This main drawback of the solar energy can be very efficiently solved by storing and later evolving of accumulated heat from solar gains according to the day-night as well as the seasonal, i.e. summer-winter cycle. A novel solution described in this contribution is an opportunity to reduce significantly the energy demands for heating/cooling and heating of Domestic Hot Water (DHW). The costs for construction and operation of future buildings are considerable reduced if the heat comfort is maintained by aluminium foam heating/cooling ceiling heat exchangers that allow storage of the heat in the form of latent heat of phase transition of Phase Change Materials (PCMs) impregnated in the porous structure of aluminium foam for later use or, for removal of undesirable heat to the building surroundings during comparatively colder summer nights.

Green fabrication of zinc oxide nanospheres by aspidopterys cordata for effective antioxidant and antibacterial activity

Prashant B. Chouke; Ajay K. Potbhare; Ganesh S. Bhusari; Subhash Somkuwar; Dadamia PMD Shaik; Raghvendra K. Mishra; Ratiram Gomaji Chaudhary

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 355-360
DOI: 10.5185/amlett.2019.2235

The present work portray the Aspidopterys Cordata (AC) leaf extract-assisted fabrication of zinc oxide nanospheres (ZnO NSs) using an eco-friendly approach for antibacterial and antioxidant activity. As fabricated ZnO NSs were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), energy dispersive X-ray diffraction (EDX), UV-Visible diffuse reflectance spectroscopy (UV-DRS), Raman, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscope (TEM) for authenticate the structure, shape, size, chemical state, and morphological facet. XRD pattern showed the strong and intense diffraction peaks indicating the formation of crystalline ZnO NSs with hexagonal phase. Further, EDX revealed the formation of highly pure ZnO with signals of Zn and O elements. UV–DRS reveals absorption band at 370 nm, assigned to the intrinsic band-gap absorption of ZnO, owing to the electron transitions from valence band to conduction band. TEM images inveterate the formations of ZnO NSs with mean particle size of 11.6 nm. The antibacterial activity of ZnO NSs was examined against gram-positive (Staphylococcus aureus) and gram-negative (Proteus vulgaris, Escherichia coli, and Klebsiella pneumonia) human pathogenic bacteria using ZnO NSs by agar-well diffusion method. Furthermore, ZnO NSs exhibited significant antioxidant activity against scavenging 1, 1-Diphenyl-2-picrylhydrazyl (DPPH) free radicals.

Effect of diamantane on the thermal stability of cryomilled aluminum alloy

Walid M. Hanna; Farghalli A. Mohamed

Advanced Materials Letters, 2019, Volume 10, Issue 5, Pages 361-365
DOI: 10.5185/amlett.2019.2282

The thermal stability behavior of Al-5083 cryomilled nanocrystalline powders stabilized by diamantane nanoparticles was studied in comparison with the alloy without diamantane. Nanocrystalline Al 5083 powders were produced by mechanical milling in a liquid nitrogen medium. The results revealed that Al 5083 with diamantane showed higher thermal stability than the cryomilled alloy without diamantane in the temperature limit from 473 °K to 773 °K (0.56 to 0.91Tm) for various annealing times from 0.5 h to 48 h. In this regard, calculations showed that while the grain size was still in the nano scale in the presence of diamantane, it was in the ultrafine range (> 150 nm) in the absence of diamantane. The above finding was qualitatively explained in terms of Zener’s concept.