Enhanced photosensitive properties of single-crystal formamidinium lead bromide iodine (FAPbBr2I) based photodetector

In this work, the growth of formamidinium (FA) based mixed halide perovskite single-crystal via inverse temperature crystallization method is investigated and characterized to detect its photosensitive properties. The structural characterization...

Size-tunable MoS2 nanosheets for controlling crystal morphology and residual stress in sequential-deposited perovskite solar cells over 22.5% efficiency

The two-step crystallization method for perovskite film fabrication has been recognized as an efficient process to obtain high-performance perovskite solar cells (PSCs). However, many issues related to the as-prepared lead...

Hierarchical living assembly: fabrication and visualization of multiblock microstructures

Nature possesses a powerful ability to assemble multiple complex structures to fabricate hierarchical biological structures in a living-assembled way. However, it is still a huge challenge for artificial systems to fabricate and characterize hierarchical living assemblies with well-defined and controllable but complex structures. In this work, we proposed a new concept for the fabrication of multiblock fluorescent microcolumns, which relies on the cooperation between the controllable host–guest complexation based on cucurbit[8]uril (CB[8]) and the living assembly of nanotubular supramolecular polymers composed of CB[8] and NaBr in aqueous solution. By using the complexation of CB[8] with different guest numbers of luminogens with aggregation-induced emission (AIEgens) characteristics, and the difference in affinity between CB[8] and different types of AIEgens, the concentration-controlled and self-sorting-controlled sequential living assembly are realized, respectively. Correspondingly, multiblock fluorescent microcolumns with different fluorescence emission are fabricated, and the molecular structure of each fluorescent block is analyzed by single crystal X-ray diffraction measurement. In addition, the living assembly of multiblock fluorescent microcolumns is visualized, understood, and regulated with the aid of AIEgens. The method developed here is expected to be extended to more guest molecules of CB[8] and also provides a referential crystallization method for CB[8]-based complexes.

PREPARATION OF FEED-GRADE MONOCALCIUM PHOSPHATE BY CRYSTALLIZATION IN AQUEOUS MEDIUM: CALCULATION AND EXPERIMENTS

In this paper, we present the results of calculation, and experiments for the preparation of feed-grade monocalcium phosphate by crystallization method in phosphoric acid solution. Some parameters influence to the production such as the reaction and crystallization temperature, the ratio of recycle mother liquor to reactant mixture have been investigated. The results show that the crystallization method in the preparation of monocalcium phosphate will give product with higher quality, less impurities that will be suitable for animal feed additives.

Electrical properties of cation-substituted Ag7(Si1–xGex)S5I single crystals

High-quality single crystals of Ag7(Si1–xGex)S5I (x = 0.2, 0.4, 0.6, 0.8) solid solutions are grown from the solution–melt by vertical zone crystallization method. The measurements of electrical conductivity of Ag7(Si1–xGex)S5I solid solutions were performed using the impedance spectroscopy method within the frequency range from 10 Hz up to 2·106 Hz and temperature interval 293–383 K. Ionic and electronic components of electrical conductivity, as well as their ratios, were determined using the Nyquist plots.

Volatile Profiling Aided in the Isolation of Anti-Proliferative Lupeol from the Roots of Clinacanthus nutans (Burm. f.) Lindau

Isolation of anti-proliferative compounds from plants is always hindered by the complexities of the plant’s nature and tedious processes. Clinacanthus nutans (Burm. f.) Lindau is a medicinal plant with reported anti-proliferative activities. Our study aimed to isolate potential anti-proliferative compounds present in C. nutans plant. To start with, for our study, we came up with a strategy by first profiling the volatile compounds present in the leaf, stem and root of C. nutans using GC-MS. Comparing the plant’s volatile profiles greatly narrowed down our target of study. We decided to start with the isolation and characterization of a pentacyclic terpenoid, i.e., lupeol from the roots of C. nutans, as this compound was found to present abundantly in the roots compared to the leaf or stem. We developed a simple maceration and re-crystallization method, without the necessity to go through the fractionation or column chromatography for the isolation of lupeol. Characterizations of the isolated compound identified the compound as lupeol. The anti-proliferative activity of the isolated lupeol was further investigated against the MCF-7 cell line, which showed comparable anti-proliferative activity with the authentic lupeol and camptothecin. Our strategy to profile every part of the plant first, followed by selection of the most suitable plant part and targeted compound proved useful for further isolation and characterization bioactive compound from C. nutans.

Obtaining Cocrystals by Reaction Crystallization Method: Pharmaceutical Applications

Cocrystals have gained attention in the pharmaceutical industry due to their ability to improve solubility, stability, in vitro dissolution rate, and bioavailability of poorly soluble drugs. Conceptually, cocrystals are multicomponent solids that contain two or more neutral molecules in stoichiometric amounts within the same crystal lattice. There are several techniques for obtaining cocrystals described in the literature; however, the focus of this article is the Reaction Crystallization Method (RCM). This method is based on the generation of a supersaturated solution with respect to the cocrystal, while this same solution is saturated or unsaturated with respect to the components of the cocrystal individually. The advantages of the RCM compared with other cocrystallization techniques include the ability to form cocrystals without crystallization of individual components, applicability to the development of in situ techniques for the screening of high quality cocrystals, possibility of large-scale production, and lower cost in both time and materials. An increasing number of scientific studies have demonstrated the use of RCM to synthesize cocrystals, mainly for drugs belonging to class II of the Biopharmaceutics Classification System. The promising results obtained by RCM have demonstrated the applicability of the method for obtaining pharmaceutical cocrystals that improve the biopharmaceutical characteristics of drugs.

Evaluating the Methods Used for the Regeneration Process of Copper-Zinc Solutions

The purpose of this study was to investigate the physicochemical particularities of the regeneration processes that occur in spent sulphate copper-zinc solutions using the reagent methods of crystallization, cementation, and sedimentation. A comparative analysis of the results of the studies of regeneration processes has shown that the content of the extraction of Cu2+ and Zn2+ ions by the crystallization method makes up to 97.2% and 49.7%, respectively; by the contact displacement method to 99.9% and 95.4%, respectively; and by the deposition method it makes up to 99.9% and 99.9%, respectively. The presented study can be used for improvements in the electroplating productivity.