Cost-affordable titanium: The component fabrication perspective

Titanium is the material of choice for a wide variety of applications. However, because of its relatively high price—a result of extraction and processing costs—it is used only when it is the only choice. This paper will overview the potential areas that are amenable to cost reduction for titanium products, emphasizing all steps in component fabrication from extraction and processing to the fabrication of final parts.     

Are current concerete strength tests suitable for high strength concrete?

Some important factors are investigated that may have an effect on compression test results of high strength concrete, including the size and shape of the test specimen as well as the mould material. Compression tests were performed on 6 different specimen types with a total of 360 specimens cast from 18 different high strength concrete mixtures (f′_c=82–117 MPa). The compressive strengths of the different specimen types were compared and conversion factors between them were established. The comparative results indicate that for each 50 mm increase in cube size there is a ～5% drop in the compressive strength. It was also found that the concrete strength of 150 mm×300 mm cylinders was, on average, 94.5% of the 150 mm cube strength. Moreover, plastic moulds yielded concrete with a strength lower than that of the concrete cast from iron moulds, and the reduction in compressive strength to the plastic moulds increased with increasing mould size.     

SIFO–VM/TIM universal biquad filter using single DVCCTA with fully CMOS realization

Analog Integrated Circuits and Signal Processing - In the presented paper, a new biquad topology is reported and described wherein five various types of filtering responses in each voltage mode and...     

Bioresorbable Scaffolds with Biocatalytic Chemotherapy and In Situ Microenvironment Modulation for Postoperative Tissue Repair

New biomaterials with antitumor and tissue repair function have become increasingly important for the postoperative care of melanoma surgery, which could prolong the tumor-free survival of patients while simultaneously facilitating the reconstruction of the trauma tissue. For this purpose, a bioresorbable composite scaffold is designed which is fabricated by depositing therapeutic amorphous calcium carbonate (ACC)-based nanoformulations in gelatin/polycaprolactone (GP) nanofibers via electrospinning. The ACC nanoformulations are integrated with Fe²⁺-preactivated bleomycin to deliver biocatalytically enhanced therapeutic effect while the hydrolysable ACC contents can act as proton scavengers to ameliorate the tumor tissue acidity in situ, leading to sustained inhibition on tumor recurrence and metastasis. The acid-triggered ACC decomposition also releases Ca²⁺ to activate the downstream Wnt/β-catenin signaling pathways, which can cooperate with the healing effect of the GP substrate and accelerate wound regeneration. The nanoengineered scaffold can be useful as a supplementary treatment for the postoperative management of melanoma.     

Adaptive Power Control Scheme for Mobile Wireless Sensor Networks

Wireless Personal Communications - One of the major factors that affects the performance of wireless sensor networks (WSN) is its limited battery capacity. Mobile wireless sensor networks (MWSN)...     

Synthesis and application of calix[4]arene based resin for the removal of azo dyes

The present study describes a novel synthetic method for the immobilization of calix[4]arene (II) onto the surface of modified Amberlite XAD-4 resin (4), which does not require the derivatization of calixarene moiety. The novel calix[4]arene based resin (C4 resin) 5 was used as sorbent for the removal of azo dyes. Batch-wise sorption study was carried out and observed that the C4 resin (5) is more effective as compared to compound II as well as pure Amberlite XAD-4 resin (1) to remove the selected dyes [i.e. Reactive Black-5 (RB-5), Reactive Red-45 (RR-45) and Congo Red (CR)]. The effect of sorbent dosage and pH on % sorption was studied. During the extraction process, various kinds of interactions such as electrostatic repulsion, deprotonation of the hydroxyl groups of C4 resin, dissociation of reactive dyes into anions/cations and structural variations were monitored and found that they are highly pH dependent.     

Nonionic surfactant based thymoquinone loaded nanoproniosomal formulation: in vitro physicochemical evaluation and in vivo hepatoprotective efficacy

Context: The present study was carried out to formulate thymoquinone proniosomal formulation (TQP) and evaluate their efficacy in methotrexate (Mtx) induced hepatotoxicity in rats.

Objective: The objective of the study was to explore a new therapeutic approach focusing on hepatoprotective activity using thymoquinone proniosomal formulation.

Material and methods: TQP was formulated using span60, cholesterol and phospholipid by film hydration technique. The animals were divided into six groups with five animals each receiving different treatments for 7?days. On the 8th day, rats were anesthetized with ether, blood samples were withdrawn, livers were dissected out for biochemical tests and histopathological examinations.

Results and discussion: The size of vesicle was found to be in the nanometric range with higher entrapment efficiency. The high entrapment efficiency is probably due to the lipophilic character of TQ. The morphological structure showed the outline and core of the well-identified spherical vesicle, and also displaying the retention of sealed vesicular structure. The release of TQ from developed formulation was found to be significantly higher compared to control. Mtx treated rats showed significant elevation in ALT, AST, ALP and TBARs, whereas, TQP treated group showed significant reduction.

Conclusion: The developed formulation (TQP) significantly inhibited the elevated levels of serum marker enzymes and showed improved histopathological deformities.     

Properties of Injection Molded Composites Containing Corn Fiber and Poly(Vinyl Alcohol)

Composites based on natural polymers alone are extremely sensitive to moisture and their mechanical properties deteriorate upon the absorption of water, limiting their usefulness in practical applications. Ongoing research cooperation between USDA and the University of Pisa, Italy, has yielded several composites based on poly(vinyl alcohol) (PVA) and corn fibers (CF). In this study, variable amounts of CF and PVA were processed in the presence of both dry and liquid plasticizers, glycerol and pentaerythritol. Cornstarch was introduced in the formulation to reduce the cost and to further increase the composition of natural components in the composites. Composites made with as low as 30% PVA were injection molded into tensile bars and evaluated. The addition of starch moderately reduced the tensile properties of the composites, lowering the elongation (∼600% to 400%) and increasing Young's modulus (∼36 MPa to ∼100 MPa) while the ultimate tensile strength remained constant at about 8 MPa. Composites prepared from CF and PVA showed little change in their mechanical properties even after conditioning them at various relative humidities, or after soaking in water. Composites tested after storage for one year, at 50% relative humidity and 23°C, exhibited mechanical properties similar to those of freshly prepared composites. *Names are necessary to report factually on available data; however the USDA neither guarantees nor warrants the standards of the product and the use of the name USDA implies no approval of the product to the exclusion of others that may also be suitable.     

Effect of Oxygen Partial Pressure and Temperature on the Oxidation Behavior of SiB6

Metallurgical and Materials Transactions B - The oxidation kinetics of silicon hexaboride (SiB6) was studied at different partial pressures of oxygen. The specific weight gain was measured at...     

Interfacial liquid crystalline mesophase domain on carbon nanofillers in aromatic thermosetting copolyester matrix

This work presents the formation process and thermophysical characteristics of preferentially oriented interfacial liquid crystalline (LC) mesophase domain emerging around graphene nanoplatelet (GNP) particles within an amorphous aromatic thermosetting copolyester (ATSP) matrix. Acetoxy‐ and carboxylic acid‐capped matched oligomers of ATSP interact with oxygen‐bearing functional groups on the GNPs during the thermal polymerization process which tethers the nanofillers to the crosslinked polymer backbone. Upon curing, a nematic phase LC network develops at the nanoparticle and matrix interface via the crystalline carbonaceous structure induced local ordering effects. The LC region exhibits a thermally reversible phase transition characteristic; attains an isotropic morphology through a heating cycle and reverses to the nematic form following a subsequent cooling cycle. Solid‐state nuclear magnetic resonance spectroscopy analysis reveals the presence of a robust interfacial attachment between the GNPs and ATSP backbone. The strong covalent conjugation induces a marked upshift in the glass transition temperature (T_g) in the ATSP‐GNP nanocomposites. Introduction of an LC interlayer region surrounding the nanofillers facilitated by a strong interfacial attachment mechanism could help to optimize the performance of polymer nanocomposites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46584.