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Ambient humidity plays an important role in the fields of industrial and agricultural production, food and drug storage, climate monitoring, and maintenance of precision instruments. To sense and control humidity, humidity-responsive actuators that mimick humidity responsive behavior existing in nature, have attracted intense attention. The most common and important class of humidity actuators is active bilayer structures. However, such bilayer structures generally show weak interfacial adhesion, tending to delaminate during frequent bending and restoration cycles. In this work, to address this problem, a novel monolayer humidity-driven actuator with no adhesive issue is developed by integrating the swellable metal–organic frameworks (MIL-88A) into thermoplastic polyurethane films. The proposed actuators display excellent humidity response that under the conditions of relative humidity simulated with saturated salt solution, the MIL-88A/polyurethane composite films show good self-folding response and stability for recycling use. In addition, a deep insight into the self-folding of the composite films is also provided and a new response mechanism is proposed. In this case, the results show that both the preparation method and response properties of the humidity actuators are improved. Therefore, it suggests a new promising way to develop and design flexible humidity actuators.

Three new perovskite-like hybrid iodobismuthates with two quaternary ammonium cations, namely (BnNEt3)3(Bi2I9) (1) (BnNEt3)4(Bi4I16) (2) and (n-Bu4N)2n(Bi4I14)n (3) (Bn = benzyl, n-Bu = n-butyl), have been synthesized by reacting BiI3 with the quaternary ammonium iodide in molar ratio 2:3 (1), 1:1(2), and 2:1 (3), respectively. All hybrids were characterized by elemental analysis, X-ray diffraction and UV–Vis spectroscopic analysis. Single-crystal X-ray diffraction revealed that hybrids 1 and 2 are di-nuclear and tetra-nuclear cluster structures respectively, while 3 is a polymeric chain structure based on a (Bi4I14) tetra-nuclear cluster unit. Their optical band-gaps have been determined as 2.19 eV(1), 2.16 eV(2), 2.02 eV(3), respectively. The optical band gaps exhibit a structure-related decrease from 1 to 3, in agreement with their color changes and the density functional theory (DFT) calculation results. The DFT calculations also reveal that there is a inversely proportional relationship between the optical Eg and the aggregation degree of the BiI6 octahedra in the hybrid iodobismuthate clusters.

Silver microparticles have inspired much research interest due to their enhanced properties for use in optical, electric, catalytic, and magnetic applications. One such use is as electrically conductive filler for printed electronics. A manufacturing approach has been developed to prepare low-curing-temperature silver pastes. Firstly, silver flakes were synthesized directly by a one-step aqueous-phase reduction reaction, using silver nitrate as silver salt precursor and iron(II) sulfate heptahydrate as reducing agent. Various silver flake samples were synthesized by controlling experimental parameters such as the reaction temperature, surfactant concentration, and reducing agent concentration. The obtained silver powders were characterized by x-ray diffraction analysis, scanning electron microscopy, and dynamic light scattering measurements. The results revealed that the morphology of the silver powders was a plate-like structure with diameter of 1 μm to 1.5 μm and thickness of 30 nm. The prepared silver flakes were then used directly without ball milling to prepare low-curing-temperature silver pastes. The bulk resistivity of a line screen-printed using silver paste containing 48 wt.% (34 ± 5 vol.%) silver flakes and cured at 140°C for 30 min in air was about (1.773 ± 0.118) × 10−6 Ω m. More importantly, the prepared screen-printed patterns exhibited excellent durability in terms of peel strength and folding endurance.

Laser scanning is widely used in on-line industrial 3D inspection, cultural heritage conservation and reverse engineering. However, in the traditional laser scanning, the most widely-used approach is based on the projection of a single directional laser stripe over an object. Because the width of the laser stripe is physically difficult to compress enough to be fine at the edge of the object, the traditional measurement method is not accurate for edge measurements. This paper proposes an edge sensitive 3D measurement system which is fast and accurate, using two directional laser stripes scanning with a laser projector. Scanning metal edge steps and complex surface edge with this system only require a single scanning to perform 3D reconstruction. So this scanning method has the advantages of high efficiency, high speed and edges with high precision.

s During the course of reinvestigating the reactions of iodate anion and lanthanide cations under different conditions, the single-crystal structure of Eu(IO 3 ) 3 (H 2 O)·H 2 O ( 1 ) and a series of corresponding nanoplate materials were obtained. X-ray single-crystal diffraction reveals that 1 is characterized as a two-dimensional inorganic layered structure with an unprecedented binodal (3, 5)-connected net of (3·4·5)(3 2 ·4 2 ·5·6 3 ·7 2 ) topology. A simple solution reaction method has also been founded for synthesizing corresponding Ln(IO 3 ) 3 (H 2 O)·H 2 O (Ln = Nd, Eu, Gd, Tb, Dy) nanoplate materials. PXRD measurements have shown that the size of the particles increases along with the raise of the adopted synthesis temperature. Their thermogravimetric analyses (TGA) and luminescence properties have also been discussed. The strong red/yellow emission for materials of Eu III /Tb III was observed, respectively.