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The emergence of planar meta‐lenses on flexible materials has profoundly impacted the long‐standing perception of diffractive optics. Despite their advantages, these lenses still face challenges in design and fabrication to obtain high focusing efficiency and resolving power. A nanofabrication technique is demonstrated based on photolithography and polyimide casting for realizing membrane‐based multilevel phase‐type Fresnel zone plates (FZPs) with high focusing efficiency. By employing advantageous techniques, these lenses with nanostructures are directly patterned into thin polyimide membranes. The computational and experimental results have indicated that the focusing efficiency of these nanostructures at the primary focus increases significantly with increasing the number of phase levels. Specifically, 16‐level phase lenses on a polyimide membrane can achieve a focusing efficiency of more than 91.6% of the input signal (9.5 times better than that of a conventional amplitude‐type FZP) and focus light into a diffraction‐limited spot together with very weak side‐lobes. Furthermore, these lenses exhibit considerably reduced unwanted diffraction orders and produce extremely low background signals. The potential impact of these lenses extends across various applications and techniques including microscopy, imaging, micro‐diffraction, remote sensing, and space flight instruments which require lightweight and flexible configurations. [ABSTRACT FROM AUTHOR]

Kombucha tea is a traditional beverage originating from China and has recently gained popularity worldwide. Kombucha tea is produced by the fermentation of tea leaves and is characterized by its beneficial properties and varied chemical content produced during the fermentation process, which includes organic acids, amino acids, vitamins, minerals, and other biologically active compounds. Kombucha tea is often consumed as a health drink to combat obesity and inflammation; however, the bioactive effects of kombucha tea have not been thoroughly researched. In this study, we reveal the underlying mechanisms of the beneficial properties of kombucha tea and how they protect against obesity and inflammation by studying Drosophila models. We established an inflammatory Drosophila model by knocking down the lipid storage droplet‐1 gene, a human perilipin‐1 ortholog. In this model, dysfunction of lipid storage droplet‐1 induces inflammation by enhancing the infiltration of hemocytes into adipose tissues, increasing reactive oxygen species production, elevating levels of proinflammatory cytokines, and promoting the differentiation of hemocytes into macrophages. These processes are regulated by the c‐Jun N‐terminal Kinase (JNK) pathway. Using this unique Drosophila model that mimics mammalian inflammation, we verified the beneficial effects of kombucha tea on reducing tissue inflammation. Our data confirms that kombucha tea effectively improves inflammatory conditions by suppressing the expression of cytokines and proinflammatory responses induced by lipid storage droplet‐1 dysfunction. It was found that kombucha tea consumption alleviated the production of reactive oxygen species and activated the JNK signaling pathway, signifying its potential as an anti‐inflammatory agent against systemic inflammatory responses connected to the JNK pathway. Kombucha tea reduced triglyceride accumulation by increasing the activity of Brummer (a lipase), thereby promoting lipolysis in third‐instar larvae. Therefore, kombucha tea could be developed as a novel, functional beverage to protect against obesity and inflammation. Our study also highlights the potential use of this innovative model to evaluate the effects of bioactive compounds derived from natural products. [ABSTRACT FROM AUTHOR]

The southern Baltic Sea is a peculiar area, where the Sorgenfrei-Tornquist Zone (STZ), stretching from Bornholm into the North Sea, connects to the Teisseyre-Tornquist Zone (TTZ) that continues SE up to the Black Sea. In this study, we show the structure and evolution of this controversially debated area, both on crustal and basin scale, by using three seismic reflection profiles combined with 2-D potential field data. The results demonstrate that the southern Baltic Sea is underlain by a thick crust of the East European Craton with a Moho depth in the range of 38-42 km. The overall crustal architecture is shaped by three phases of localized stretching in the early Paleozoic, Devonian-Carboniferous, and Permian-Mesozoic. The most spectacular feature of the southern Baltic Sea is a zone of thick-skinned compressional deformation produced by Late Cretaceous-early Paleogene inversion, including a system of thrusts and back thrusts penetrating the entire crust in an 80-90 km wide inversion zone. ENE-vergent thrusts are traced from the top of the Cretaceous down to the Moho and they are accompanied by back thrusts of opposite vergence, also reaching the Moho. Inversion tectonics resulted in the uplift of a block of cratonic crust as a pop-up structure, bounded by thrusts and back thrusts, and the displacement of the Moho within the STZ and TTZ. The similar mechanism of intra-cratonic inversion was recognized for the Donbas Foldbelt in eastern Ukraine, and it may be characteristic of rigid cratons, where deformation is localized in a few preexisting zones of weakness. [ABSTRACT FROM AUTHOR]

JC virus (JCV) causes progressive multifocal leukoencephalopathy in immunocompromised patients. The prevalence and genotype patterns of JCV vary between different geographical regions. This study was done to investigate the prevalence and genotype distribution of JCV in patients with hematological malignancies in Vietnam. A total of 48 urine samples were collected from patients with hematological malignancies. DNA was extracted and detection of JCV was by nested‐polymerase chain reaction. Sequence analysis was obtained and a phylogenetic tree was constructed for genotyping of JCV. Twenty‐seven (56.25%) urine samples tested positive for JCV. JCV genotype 7 was only observed in this study. Subtype analysis showed that JCV subtype 7A was the most commonly prevalent, followed by 7B1 and 7C1. Other subtypes were not detected in this population. There were no significant differences associated with age, gender, and biochemical parameters between patients with JCV and without JCV excretion in urine. The present study showed a high prevalence of JCV in the urine of patients with hematologic malignancies. The most common genotype found in this population was JCV subtype 7A. [ABSTRACT FROM AUTHOR]

All gibbon species (Family: Hylobatidae) are considered threatened with extinction and recognized on the International Union for Conservation of Nature Red List of Threatened Species. Because gibbons are one of the most threatened families of primates, monitoring their status is now critically important. Long‐term monitoring programs applying occupancy approaches, in addition to assessing occurrence probability, improves understanding of other population parameters such as site extinction or colonization probabilities, which elucidate temporal and spatial changes and are therefore important for guiding conservation efforts. In this study, we used multiple season occupancy models to monitor occurrence, extinction, and colonization probabilities for northern yellow‐cheeked crested gibbon Nomascus annamensis in three adjacent protected areas in the Central Annamites mountain range, Vietnam. We collected data at 30 listening posts in 2012, 2014, and 2016 using the auditory point count method. Occurrence probabilities were highest in 2012 (0.74, confidence interval [CI]: 0.56–0.87) but slightly lower in 2014 (0.66, CI: 0.51–0.79) and 2016 (0.67, CI: 0.49–0.81). Extinction probabilities during the 2012–2014 and 2014–2016 intervals were 0.26 (0.14–0.44) and 0.25 (0.12–0.44), respectively. Colonization probabilities during 2012–2014 were 0.44 (0.19–0.73) and between 2014 and 2016 was 0.51 (0.26–0.75). Although local site extinctions have occurred, high recolonization probability helped to replenish the unoccupied sites and kept the occurrence probability stable. Long‐term monitoring programs which use occurrence probability alone might not fully reveal the true dynamics of gibbon populations. We strongly recommend including multiple season occupancy models to monitor occurrence, extinction, and colonization probabilities in long‐term gibbon monitoring programs. [ABSTRACT FROM AUTHOR]

Abstract: Extrusion tectonics forced by plate collisions shape continents not only through lateral terrain displacement and mountain building but also through massive rifting and basin development. The rift system underneath the Gulf of Tonkin, Vietnam, constitutes a world‐class example of how extrusion tectonics drives continental rifting and transtensional basin development. Rifting and the Song Hong and Beibuwan Basin evolution are compared with the development of the Ailao Shan‐Red River Shear Zone (ASRRSZ) that accommodated the extrusion of Indochina forced by the Indian‐Eurasia collision. Rifting occurred during later Eocene‐Late Oligocene time forced by ASRRSZ left‐lateral shearing. Latest Oligocene‐earliest Miocene transpression and inversion brought rifting to a halt, after which left‐lateral shearing decreased. Paleogene rift systems extended along the trail of the ASRRSZ now outlined by lower to midcrustal metamorphic core complexes. Most of these rift systems were probably inverted and removed during the latest Oligocene‐earliest Miocene, however. The metamorphic core complexes are suggested to represent the lower to midcrustal roots of these transtensional rift basins exhumed by inversion. Rift termination in the northern Gulf of Tonkin and exhumation of the metamorphic core complexes coincided with cessation of Paleogene rifting along the western South China Sea, and a common causal mechanism is speculated. [ABSTRACT FROM AUTHOR]

Medium-sized rings, particularly the corresponding cyclic peptides, are challenging synthetic targets. In the present study, we report an approach to medium-sized cyclic peptides through targeted formation and collapse of cyclol intermediates. This methodology operates on β-amino imides derived from 2,5-diketopiperazines and offers a straightforward transition from frequently examined scaffolds in drug discovery to a rarely visited class of medium-sized rings. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Cosmetic Science is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

When activated by an acylating agent, pyridine boronic esters react with organometallic reagents to form a dihydropyridine boronic ester. This intermediate allows access to a number of valuable substituted pyridine, dihydropyridine, and piperidine products. [ABSTRACT FROM AUTHOR]

This study presents an assessment of the vegetable oil extraction from coriander fruits through mechanical pressing, more specifically twin-screw extrusion. This comprises an evaluation of the oil recovery obtained and its respective quality, as well as the specific mechanical energy, representing an economical point of view. With regard to the extrusion optimization, the screw configuration, the device's filling coefficient and the pressing temperature were varied. The screw configuration was shown to exhibit a key influence on the extraction efficiency and oil recoveries of at least 40 % were reached when the pressing zone was positioned immediately after the filter and consisted of 50 mm long, reverse screws with a -33 mm pitch. Furthermore, with a device's filling coefficient of 39.4 g/h rpm and a pressing temperature of 120 °C, an oil recovery of 47 %, the highest of this study, was reached with concurrent low energy consumption. Next to this, operating parameters of 47.1 g/h rpm and 80 °C resulted in the production of a press cake with the lowest residual oil content (15 %) in this study, although this also involved a significant increase in the filtrate's foot content. All the produced oils were of acceptable quality (<1.5 % acidity), showed high petroselinic acid content (73 %), and were pleasantly scented. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Cosmetic Science is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although much research has been conducted on wheat flour dough rheology, the principal focus has been the role of the protein fraction. Starch is the main component of flour and plays a key role in dough dynamic properties, particularly during heating. This study assesses the effect of two different waxy flours, a durum and a bread wheat, and their blends with commercial bakers' flour on dough rheology during heating with a concurrent investigation into baking performance. Both waxy flour blends produced similar effects on dough rheological behaviour despite differences in protein content, acting to delay gelatinisation and reduce storage modulus. The main effects in bread were to increase loaf expansion during baking and reduce loaf firmness. It is postulated these effects are largely water mediated, with the higher swelling ability of the waxy starch granules reducing overall water availability and driving complete gelatinisation to higher temperatures. [ABSTRACT FROM AUTHOR]

Room-temperature deformation and fracture behaviors under microcompression of single crystal β-silicon nitride (Si3N4) micropillars were investigated. Pillars were fabricated by focused ion beam ( FIB) in large Si3N4 grains, located close to the basal and prismatic orientations, selected by electron backscatter diffraction ( EBSD). The micromechanical test and the damage characterization were performed by nanoindentation and scanning electron microscopy ( SEM), respectively. The elastic, plastic, and fracture properties, such as Young's modulus, yield stress, and rupture stress are considerably influenced by the pillar orientation. The activation of the [ABSTRACT FROM AUTHOR]

Thermoelastic stress analysis (TSA) has been around for the past 30 years, but to date, it is still a very much underrated and under-utilised experimental technique. Although there are devoted groups of practitioners in some industries, this technology is not well known within the aerospace sector. In contrast, the Aerospace Division of the Defence Science and Technology Organisation (DSTO) in Australia has been in the forefront of this technology for some time, achieving many pioneering feats. This paper gives a brief introduction to the development of this technology from a historical perspective, then focuses on a number of innovations that have stemmed from DSTO, including the development and application of the world's first focal plane array based TSA system and, more recently, the development of small and robust microbolometer based systems. For the latter, it is shown that despite nominally poorer temperature sensitivities, they make ideal TSA devices and can in some cases outperform their much more expensive photon detector counterparts. Because of this, together with the enormous practical advantages of microbolometers, the future of TSA is shown to be brighter than ever. Specifically, it is argued that such TSA systems can play a major role in the pervasive and persistent surveillance of full scale fatigue testing of aircraft structures. By detecting both design and developing faults early, it can effectively relieve cost and schedule penalties that are often associated with unanticipated failures. To realise this capability, integration of this technology with autonomous systems will be important, and some preliminary but promising results from a technology demonstrator program are presented. [ABSTRACT FROM AUTHOR]

Due to its rarity, cervical thymic cyst is seldom included in the differential diagnosis of a neck mass. Approximately 80 cases have been reported thus far, and most of these cases have occurred asymptomatically in children and adults. Only 5 cases have involved patients younger than 1 year of age. The authors report four new patients with thymic cyst in the neck. Two of the patients were newborns in whom the cyst caused airway obstruction and dysphagia. All four patients underwent successful resection of the lesions, with complete resolution of symptoms. The embryology, histopathology, and differential diagnosis of cervical thymic cysts are also reviewed. The authors recommend that despite its infrequent occurrence cervical thymic cyst should be considered in the evaluation of neck masses in children. [ABSTRACT FROM AUTHOR]

The microstructural and mechanical properties of an ultrafine-grained (UFG) Al-Zn alloy processed by high-pressure torsion (HPT) are investigated using depth-sensing indentations, focused ion beam, scanning electron microscopy and scanning transmission electron microscopy. Emphasis is placed on the microstructure and the effects of grain boundaries at room temperature. The experiments show the formation of Zn-rich layers at the Al/Al grain boundaries that enhance the role of grain boundary sliding leading to unique plastic behavior in this UFG material. The occurrence of significant grain boundary sliding at room temperature is demonstrated by deforming micro-pillars. Our results illustrate a potential for using UFG materials as advanced functional materials in electronic microdevices. [ABSTRACT FROM AUTHOR]

SUMMARY The electromagnetic modeling of antennas and radio frequency devices has become increasingly challenging as the applications demand intricate and complex designs, such as fine features embedded in electrically large structures or integrated systems (e.g., antennas on vehicles). Often the design stage is further challenged by the need to find an optimal solution, which results in a numerically intensive problem. The objective of this paper is to investigate the use of graphics processing units (GPUs) in such challenging design and optimizations. Two full-wave approaches (method of moments and rigorous coupled wave analysis) are discussed along with a bio-inspired optimization technique, namely the particle swarm optimization. The inherent parallel nature of the GPUs is utilized in implementing the most numerically intensive parts of these full-wave methods. Furthermore, the independent search mechanism employed by the particle swarm optimization in its agent-based search renders itself to parallelism offered by GPUs. The paper demonstrates the acceleration achieved by the GPUs in designing a variety of radio frequency structures such as reconfigurable patch antennas and antireflective surfaces. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the interpolymer association between Poly(sodium styrene sulfonate) (PSSNa) and Poly(vinyl alcohol ) (PVA)in aqueous solution. The study used Couette-type viscosimeter to investigate the association of polymers. Results show that intermolecular hydrogen bonds between sulfonate groups of PSSNa and hydroxyl groups of PVA have affect the interpolymer association between PSSNa and PVA.

Solid organ transplant (SOT) recipients have high rates of invasive fungal infections, with Candida species the most commonly isolated fungi. The aim of this study was to identify differences between incidence rates, risk factors, clinical presentations, and outcomes of candidemia in SOT recipients and non-SOT patients. Data from the multicenter prospective Australian Candidaemia Study were examined. From August 2001 to July 2004, 24 episodes (2.2%; 24/1068) of candidemia were identified in SOT recipients. During this period, the numbers of transplanted organs included liver ( n=455), kidney ( n=1605), single lung ( n=57), bilateral lung ( n=183), heart and lung ( n=18), heart ( n=157), and pancreas ( n=62). The overall annual estimated incidence of candidemia in SOT recipients was higher (3 per 1000 transplant admissions) than in non-SOT patients (incidence 0.21 per 1000 admissions; P<0.001). The incidence and timing of candidemia post transplant was influenced by the transplanted organ type, with the majority of episodes ( n=14, 54%) occurring >6 months after renal transplantation. Risk factors for candidemia in the month preceding diagnosis were similar to non-SOT recipients except for corticosteroid therapy ( P<0.001). Antifungal prophylaxis did not select for more resistant or non- albicans Candida species in the SOT group. The 30-day all-cause mortality was similar to non-SOT patients with candidemia and remains high at 21%. All deaths in SOT recipients occurred early (within 5 days of diagnosis), underlining a need for better diagnostic tests, targeted prevention, and early treatment strategies. [ABSTRACT FROM AUTHOR]

With their genome sequenced, Anopheles gambiae mosquitoes now serve as a powerful tool for basic research in comparative, evolutionary and developmental biology. The knowledge generated by these studies is expected to reveal molecular targets for novel vector control and pathogen transmission blocking strategies. Comparisons of gene-expression profiles between adult male and nonblood-fed female Anopheles gambiae mosquitoes revealed that roughly 22% of the genes showed sex-dependent regulation. Blood-fed females switch the majority of their metabolism to blood digestion and egg formation within 3 h after the meal is ingested, in detriment to other activities such as flight and response to environment stimuli. Changes in gene expression are most evident during the first, second and third days after a blood meal, when as many as 50% of all genes showed significant variation in transcript accumulation. After laying the first cluster of eggs (between 72 and 96 h after the blood meal), mosquitoes return to a nongonotrophic stage, similar but not identical to that of 3-day-old nonblood-fed females. Ageing and/or the nutritional state of mosquitoes at 15 days after a blood meal is reflected by the down-regulation of ∼5% of all genes. A full description of the large number of genes regulated at each analysed time point and each biochemical pathway or biological processes in which they are involved is not possible within the scope of this contribution. Therefore, we present descriptions of groups of genes displaying major differences in transcript accumulation during the adult mosquito life. However, a publicly available searchable database ( ) has been made available so that detailed analyses of specific groups of genes based on their descriptions, functions or levels of gene expression variation can be performed by interested investigators according to their needs. [ABSTRACT FROM AUTHOR]

Female Anopheles gambiae mosquitoes respond to odours emitted from humans in order to find a blood meal, while males are nectar feeders. This complex behaviour is controlled at several levels, but is probably initiated by the interaction of various molecules in the antennal sensilla. Important molecules in the early odour recognition events include odourant binding proteins (OBPs), which may be involved in odour molecule transport, odourant receptors (ORs) that are expressed in the chemosensory neurones and odour degrading enzymes (ODEs). To obtain a better understanding of the expression patterns of genes that may be involved in host odour reception in females, we generated a custom microarray to study their steady state mRNA levels in chemosensory tissues, antennae and palps. These results were supported by quantitative RT PCR. Our study detected several OBPs that are expressed at significantly higher levels in antennae and palps of females vs. males, while others showed the opposite expression pattern. Most OBPs are slightly down-regulated 24 h after blood feeding, but some, especially those with higher expression levels in males, are up-regulated in blood-fed females, suggesting a shift in blood-fed females from human host seeking to nectar feeding. [ABSTRACT FROM AUTHOR]

A microarray analysis of 14 900 genes of the malaria vector mosquito, Anopheles gambiae, shows that as many as 33% (4924) of their corresponding transcription products vary in abundance within 24 h after a blood meal. Approximately half (2388) of these products increase in their accumulation and the remainder (2536) decrease. Expression dynamics of 80% of the genes analysed by expressed sequence tag (EST) projects reported previously are consistent with the observations from this microarray analysis. Furthermore, the microarray analysis is more sensitive in detecting variation in abundance of gene products expressed at low levels and is more sensitive overall in that a greater number of regulated genes are detected. Major changes in transcript abundance were seen in genes encoding proteins involved in digestion, oogenesis and locomotion. The microarray data and an electronic hyperlinked version of all tables are available to the research community at . [ABSTRACT FROM AUTHOR]

In its most common configuration, a solid oxide fuel cell (SOFC) uses an oxygen-ion conducting ceramic electrolyte membrane, perovskite cathode, and nickel cermet anode electrode. Cells operate in the 600-1000°C temperature range and utilize metallic or ceramic current collectors for cell-to-cell interconnection. Recent developments in engineered electrode architectures, component materials chemistry, cell and stack designs, and fabrication processes have led to significant improvements in the electrical performance and performance stability as well as reduction in the operating temperature of such cells. Large kW-size power-generation systems have been designed and field demonstrated. This paper reviews the status of SOFC power-generation systems with emphasis on cell and stack component materials, electrode reactions, materials reactions, and corrosion processes. [ABSTRACT FROM AUTHOR]

Alginate with a weight-average molecular mass ( M w) of approx. 9.04×105 Da was irradiated at 10–200 kGy in 4% (w/v) aqueous solution. The degraded alginate product was used to study its effectiveness as a growth promoter for plants in tissue culture. Alginate irradiated at 75 kGy with an M w of approx. 1.43×104 Da had the highest positive effect in the growth of flower plants, namely limonium, lisianthus and chrysanthemum. Treatment of plants with irradiated alginate at concentrations of 30–200 mg/l increased the shoot multiplication rate from 17.5 to 40.5% compared with control. In plantlet culture, 100 mg/l irradiated alginate supplementation enhanced shoot height (9.7–23.2%), root length (9.7–39.4%) and fresh biomass (8.1–19.4%) of chrysanthemum, lisianthus and limonium compared with that of the untreated control. The survival ratios of the transferred flower plantlets treated with irradiated alginate were almost the same as the control value under greenhouse conditions. However, better growth was attained for the treated plantlets. [ABSTRACT FROM AUTHOR]

Incidence rates of childhood cancer for the city of Ho Chi Minh are presented for the first time. For the 3-year period 1995-97, a total of 302 cancer cases were registered in children under 15 years of age, with a male to female ratio of 1.1. The overall crude rate was 78.8 and the age-standardised incidence rate was 88.4 per million person-years, which was low in comparison with other countries in eastern Asia and with the predominantly white population of Australia. Leukaemia (principally acute lymphocytic), brain tumours and lymphomas were the most common childhood neoplasms, which is consistent with the pattern observed in other registries of the region. The rate of retinoblastoma was higher than in the other regional registries. On the other hand, no cases of hepatocellular carcinoma were registered. [ABSTRACT FROM AUTHOR]

Purpose: Unoperated cataract is the leading cause of blindness in the developing world. Many developing countries now use extracapsular cataract extraction (ECCE) with intra-ocular lens insertion (IOL) in their cataract blindness-prevention programmes. To date, little research has been directed at visual outcomes and complication rates of ECCE/IOL surgery in developing countries. Methods: We conducted a follow-up study of 155 eyes approximately 12 months after ECCE/IOL surgery by eight local eye surgeons in Central Vietnam. We report the findings for the 144 eyes (93%) successfully reviewed. All subjects underwent manual ECCE with insertion of a three-piece posterior chamber IOL. All eyes were also assessed for the presence and severity of posterior capsule opacification (PCO) using a newly developed grading system. Results: Overall, 110 eyes (75%) had uncorrected visual acuities ≥6/24 and 107 eyes (74%) had best spherically corrected visual acuities ≥6/18. Some degree of PCO was found in 40% of eyes, but was graded as visually significant in only 4% of eyes. No major sight-threatening complications were noted. A portable neodymium: yttrium aluminium garnet (Nd: YAG) laser was used to perform capsulotomies on all eyes with visually significant PCO. There were no laser complications noted. Conclusions: At approximately I year after ECCE/IOL, the visual outcomes for subjects in this cohort were favourable and complication rates were low. Posterior chamber opacification was not a major cause of vision impairment in this cohort. Portable Nd: YAG lasers may provide an effective solution to the problem of visually significant PCO occurring in developing countries as a late complication of extracapsular surgery. These findings support an increasing role for ECCE/PCIOL surgery by trained local eye surgeons in developing countries. [ABSTRACT FROM AUTHOR]

Herein, the characterization of microstructures and mechanical properties of Al–Zn alloys ultrafine‐grained (UFG) by using high pressure torsion (HPT) is surveyed. Emphasis is placed on the decomposition of the solid solution structures due to the HPT process, leading to unique mechanical and plastic properties of the UFG alloys. The decomposed microstructures, the grain boundaries wetted by Zn‐rich layers, as well as the softening, grain boundary sliding (GBS) with usually high strain rate sensitivity and super‐ductility of the HPT‐processed samples are described and discussed. Furthermore, the innovation potential of intensive GBS at room temperature is briefly considered. [ABSTRACT FROM AUTHOR]

Herein, the ultrafine‐grained (UFG) 7xxx series alloy Al–4.8Zn–1.2Mg–0.14Zr demonstrates superplasticity at unusually low temperatures of 120–170 °C while maintaining its high‐strength state. The UFG structure is formed by high pressure torsion (HPT) at room temperature (RT), which leads to a considerable increase in the strength characteristics by ≈60% compared with the material after conventional heat treatment T6. It is found that the UFG alloy exhibits thermostability when testing or annealing up to 170 °C. Deforming by tensile test at a strain rate of 10−4 s−1 and 10−3 s−1, the elongation to failure at 120 and 170 °C exceeds 250% and 500%, respectively, whereas the strain rate sensitivity reaches 0.45, which is a typical value characterizing superplastic deformation. After superplastic deformation, the UFG alloy maintains 25–50% higher strength characteristics at RT than that after conventional heat treatment T6. The origin of such superior behavior of the UFG alloy is discussed. [ABSTRACT FROM AUTHOR]

Review: 55 refs. [ABSTRACT FROM AUTHOR]