materials science

The exploration of high nuclearity molecular metal oxide clusters and their reactivity is a great challenge for chemistry and materials science. Here, we report an unprecedented giant molecular cerium-bismuth tungstate superstructure formed by self-assembly from simple metal oxide precursors in aqueous solution. The compound, {[W14CeIV6O61]([W3Bi6CeIII3(H2O)3O14][B-α-BiW9O33]3)2}34- was identified by single crystal X-ray diffraction and features 104 metal centres, a relative molar mass of ~24,000 and is ca...

Prof. Qichun Zhang, Ph.D School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 E-mail: qczhang@ntu.edu.sg March 30th, 2018 Editor ACS applied materials and interfaces Dear Editor, Enclosed please find our manuscript entitled, "Thiadizoloquinoxaline-based N-heteroacenes as active elements for high-density data-storage device", by Yang Li, Zilong Wang, Cheng Zhang, Peiyang Gu, Wangqiao Chen, Hua Li, Jianmei Lu, and Qichun Zhang, which we would like to publish as a full paper in ACS Applied Materials & Interfaces...

Click polymerization, a powerful synthetic technique to construct polymers with unique structures and advanced functions, is of crucial importance in the areas of polymer and material sciences. A variety of click polymerizations such as azide-alkyne, thiol-yne, amino-yne, and hydroxyl-yne reactions have been established, wherein the catalytic systems play an indispensable role in realizing these highly practical reactions based on triple-bond building blocks, as they directly influence the efficiencies of the click polymerizations and the performances of the resultant polymers...

BACKGROUND Caustic ingestion is one of the most important injuries during childhood, which leads to serious sequel. In this study, we evaluated the clinical manifestations, endoscopic appearance, complications, and treatment results in patients with caustic ingestion in our hospital. METHODS Hospital chart of patients with caustic ingestion who admitted to Nemazee Teaching Hospital affiliated to Shiraz University of Medical Sciences during a 2-year period (2015-2016) were reviewed retrospectively. The age, sex, nature of the caustic agent, clinical presentations, grade of injury in endoscopy, degree of parents' education, site of ingestion, accidental or intentional attempts, complications, and outcomes were reviewed...

Background: The acupuncture profession is stymied by a dearth of comparative research. A review of the literature for acupuncture research reveals no meta-analyses comparing the effectiveness of different clinically popular methods/systems of acupuncture. Rather than comparing different methods/systems, acupuncture research seems more focused on determining if acupuncture, in general, works. Objectives: The aim of this Perspective is to examine the current state of acupuncture research and determine what, if any, problems or gaps in this research exist...

Purpose People with schizophrenia continue to encounter barriers to employment acquisition. The aim of this scoping study was to identify and synthesize existent evidence about the employment support needs of people diagnosed with schizophrenia. Methods Five relevant databases were used: CINAHL, Medline, PsycINFO, SCOPUS, and Web of Science. Additional material of potential interest was identified through the references of the retrieved articles. A manual search for publications from the 3 months immediately prior to the electronic search was carried out in specialized journals...

Vitellone's Social Science of the Syringe investigates epistemologies of injecting drug use. She argues for a methodology that can be simultaneously sensitive to biopolitical power regimes; the trajectories of social stratification; and the resistance, creativity and dignity of human agency. She proposes a methodological focus on the syringe-in-use as an active participant in these dynamics. Harm reduction policy and service provision frameworks have paid little attention to the phenomena of performance and image enhancing drug (PIEDs) injection...

BACKGROUND: Countries with similar health systems but different medicines policies might result in substantial medicines usage differences and resultant outcomes. The literature is sparse in this area. OBJECTIVE: To review pharmaceutical policy research in New Zealand and Australia and discuss differences between the two countries and the impact these differences may have on subsequent medicine access. METHODS: A review of the literature (2008-2016) was performed to identify relevant, peer-reviewed articles...

Scaffold-based lattice-engineered 3D DNA origami emerges as a powerful and versatile technique for the rational design and built-up of arbitrary and monodisperse DNA-based 3D nanoobjects. Relying on the unsurpassed molecular programmability of sequence-specific DNA hybridization, a long circular ssDNA strand (termed scaffold) is assembled with many short ssDNA oligomers (termed staples), which organize the scaffold into a 3D lattice in a single step leading to highest precision 3D nanoparticulate structures with high yields...

Codes of conduct have received wide attention as a bottom-up approach to foster responsibility for dual use aspects of life science research within the scientific community. In Switzerland, a series of discussion sessions led by the Swiss Academy of Sciences with over 40 representatives of most Swiss academic life science research institutions has revealed that while a formal code of conduct was considered too restrictive, a bottom-up approach toward awareness raising and education and demonstrating scientists' responsibility toward society was highly welcomed...

Molecular crystals play an important role in several fields of science and technology. They frequently crystallize in different polymorphs with substantially different physical properties. To help guide the synthesis of candidate materials, atomic-scale modelling can be used to enumerate the stable polymorphs and to predict their properties, as well as to propose heuristic rules to rationalize the correlations between crystal structure and materials properties. Here we show how a recently-developed machine-learning (ML) framework can be used to achieve inexpensive and accurate predictions of the stability and properties of polymorphs, and a data-driven classification that is less biased and more flexible than typical heuristic rules...

The standard paradigm in computational materials science is INPUT: Structure; OUTPUT: Properties, which has yielded many successes but is ill-suited for exploring large areas of chemical and configurational hyperspace. We report a high-throughput screening procedure that uses compositional descriptors to search for new photoactive semiconducting compounds. We show how feeding high-ranking element combinations to structure prediction algorithms can constitute a pragmatic computer-aided materials design approach...

Developing low-cost and efficient sensors for rapid, selective and sensitive detection of the transition metal ions in environmental and food science is very important. In this study, a novel dual-functional fluorescent "turn-on" sensor 3TP based on oligothiophene-phenylamine Schiff base has been synthesized for discrimination and simultaneous detection of both Al3+ and Fe3+ ions with high selectivity and anti-interference over other metal ions. Sensor 3TP displayed a very fast fluorescence-enhanced response towards Al3+ and Fe3+ ions with low detection limits (0...

Cyclopentanoids are omnipresent in natural products and pharmaceutically relevant compounds. Among them, cyclopenta-fused arenes and heteroarenes possess impressive biological properties and play significant role in materials science. Consequently, several noteworthy methods were developed for their synthesis over the years. In this review, we mainly described metal-free and organocatalytic approaches that led to the construction of pentannulated arenes and heteroarenes.

The twist-bend modulated nematic liquid crystal phase exhibits phenomena of fundamental importance to science; the formation of a helical pitch of nanometre scale in a fluid and the spontaneous breaking of mirror symmetry leading to a quasi-fluid state composed of chiral domains despite being composed of an achiral material. We note that this phase has only been observed for materials with two or more mesogenic units, the manner of attachment between which is always linear. In this communication we report on non-linear oligomers, with a H-shaped hexamesogen found to exhibit both nematic and twist-bend modulated nematic phases...

Exposure to ultraviolet (UV) light could cause photodamage to biomolecular systems and degrade optoelectronic devices. To mitigate such detrimental effects from the bottom up, we strategically select a photosensitive molecule pyranine and implement femtosecond electronic and Raman spectroscopies to elucidate its ultrafast photoprotection mechanisms in solution. Our results show that pyranine undergoes excited state proton transfer (ESPT) in water while this process is blocked in methanol regardless of excitation wavelengths (267, 400 nm)...

The prospect of recreating the complex structural hierarchy of protein folding in synthetic oligomers with backbones that are artificial in covalent structure ("foldamers") has long fascinated chemists. Foldamers offer complex functions from biostable scaffolds and have found widespread applications in fields from biomedical to materials science. Most precedent has focused on isolated secondary structures or their assemblies. In considering the goal of complex protein-like tertiary folding patterns, a key barrier became apparent...

Since chiral phonons were found in an asymmetric two-dimensional hexagonal lattice, there has been growing interest in the study of phonon chirality, which were experimentally verified very recently in monolayer tungsten diselenide (Science 359, 579 (2018)). In this work, we find chiral phonons with nontrivial topology in center-stacked bilayer triangle lattices. At the Brillouin-zone corners, $\bm K$($\bm K^{'}$), circularly polarized phonons and nonzero phonon Berry curvature are observed. Moreover, we find that the phonon chirality remain robust with changing sublattice mass ratio and interlayer coupling...

Luminescent nanoparticles are researched for their potential impact in medical science, but no materials approved for parenteral use have been available so far. To overcome this issue, we demonstrate that Eu3+-doped hafnium dioxide nanocrystals can be used as non-toxic, highly stable probes for cellular optical imaging and as radiosensitive materials for clinical treatment. Furthermore, viability and biocompatibility tests on artificially stressed cell cultures reveal their ability to buffer reactive oxygen species, proposing an anti-cytotoxic feature interesting for biomedical applications...

Exploration of phase transitions and construction of associated phase diagrams are of fundamental importance for condensed matter physics and materials science alike, and remain the focus of extensive research for both theoretical and experimental studies. For the latter, comprehensive studies involving scattering, thermodynamics, and modeling are typically required. We present a new approach to data mining multiple realizations of collective dynamics, measured through piezoelectric relaxation studies, to identify the onset of a structural phase transition in nanometer-scale volumes, that is, the probed volume of an atomic force microscope tip...