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Upconversion materials have attracted considerable research interest for their application in bioimaging due to their unique optical properties. NaREF4 (RE = Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) based host lattice, which is widely used for upconversion, requires expensive rare-earth elements and tedious reaction conditions. Hence there is a need to develop environmentally friendly and cost effective materials for upconversion. In this study, we propose NaBiF4 as a host material for upconversion which is based on environmentally friendly and cost-effective bismuth. NaBiF4 has not been explored as an imaging probe before. We report efficient Yb3+/Tm3+ doped NaBiF4 based upconversion submicron particles which exhibit a photostable, wide upconversion emission range (NIR-to-NIR and Vis) under NIR (980 nm) excitation, and in-vitro non-cytotoxic uptake by mammalian cancer cell lines as well as bacterial cells with a high signal to background ratio. The synthesis of the chosen host material co-doped with Yb3+/Tm3+ has not been reported earlier through such a non-aqueous quaternary reverse micelle route. Here, we functionally validate these submicron particles as viable alternatives to currently available upconversion nanomaterials and highlight their potential as luminescent probes for bioimaging. [ABSTRACT FROM AUTHOR]

Objective. Humans have limited power and require mechanization, to meet high energy demand, through equipment. We initiated this study to accumulate data from previous research to identify critical issues and approaches in implementing ergonomic principles into the design, intervention, development and assessment of manually operated equipment. Method. The literature search was carried out in scientific databases: Scopus and PubMed. Fifty-three research articles, meeting the inclusion criteria, were selected for this review. Results. The study indicated a propensity of countries with lower-middle-income and high-income groups, and of the agricultural and manufacturing sector toward research and development of manually operated equipment. A thorough study of the equipment design process revealed that health and safety was the prime motivator in the pre-design phase, an experimental prototype approach was most utilized in the design phase and a direct measurement technique was most frequently used in the post-design phase. Conclusion. The study highlights the scarcity of research in the integration of ergonomics into the design of manually operated equipment among countries with the low-income group. This study also promotes the use of virtual design and assessment techniques for cost-effectiveness. [ABSTRACT FROM AUTHOR]

A comparative epoxidation study is performed to determine the relative efficiency of the catalysts NAHC[O.sub.3] and [H.sub.2][O.sub.2] and to optimize the use of [H.sub.2][O.sub.2]. It is found that the complexes show high potential and selectivity as catalysts in the expoxidation of olefins at room temperature in the presence of NAHC[O.sub.3] as a promoter and [H.sub.2][O.sub.2] as a terminal oxidant.

The production of the ternary polar intermetallic phase [Mg.sub.5.231(8)][Sm.sub.0.231(8)][Sb.sub.4] from solid state reactions at 700-850 degrees Celsius in sealed Ta or Nb containers when the synthetic conditions took into account its characteristic incongruent melting point is reported. The results present the first example of a superstructure of a[Mg.sub.3][Sb.sub.2]-like structure with a doubled c axis induced by ordering a mixture of the larger divalent Sm and Mg ions separately within alternate layers of octahedral sites.

The phases LiMgCa(sub 10)Sb(sub 9), Mg(sub 2)Ca(sub 10)Sb(sub 9), and Li(sub 1.38(2))Sb(sub 9) are synthesized by high-temperature solid-state means and characterized by single-crystal means and property measurements. The LiMgCa(sub 10)Sb(sub 9) compound is correspondingly diamagnetic and presumably a semiconductor.