pi system
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Annealing of additional aromatic pi-system to the ligand is an effective method of influencing the luminescence of metal complexes. In this contribution we show the effect of benzannulation of the...

Constructions related to products of maximal linked systems (MLSs) and MLSs  on the product of widely understood measurable spaces are considered (these measurable spaces are defined as sets equipped with \(\pi\)-systems of their subsets; a \(\pi\)-system is a family closed with respect to finite intersections). We compare families of MLSs on initial spaces and MLSs on the product. Separately, we consider the case of ultrafilters. Equipping set-products with topologies, we use the box-topology and the Tychonoff product of Stone-type topologies. The properties of compaction and homeomorphism hold, respectively.

The competitive adsorption of aromatics and nitrogen heterocycles on the active sites of solid catalytic sulfides (Ni(Co)-MoS2 dispersed over oxidic carriers) typically causes inhibitory effects during the hydropurification of sulfur heterocycles. Contrary to this typical behavior, we report herein that it is possible to promote the scission of the C-S bond of refractory dibenzothiophene by co?feeding the above compounds during hydropurification over a conventional Ni-MoS2/Al2O3 catalyst. Particularly, we prove that at temperatures between 240 and 300°C and concentrations of dibenzothiophene between 1.0 and 3.7 wt.%, the desulfurization of dibenzothiophene is promoted by increasing its conversion up to 370% when either naphthalene, indole, or quinoline are co-fed to the reaction system. The work highlights the following: (i) lower temperatures and higher concentrations of the sulfur heterocycle enhanced the cleavage of the C-S bond from dibenzothiophene; (ii) it is possible to promote hydropurification reactions regardless of the nature of the of co-reactants; namely: a fused aromatic ring -naphthalene-, or a fused nitrogen heterocycle with a lone pair belonging to the pi-system -quinoline- or not -indole-.<br><p><a></a></p>

The competitive adsorption of aromatics and nitrogen heterocycles on the active sites of solid catalytic sulfides (Ni(Co)-MoS2 dispersed over oxidic carriers) typically causes inhibitory effects during the hydropurification of sulfur heterocycles. Contrary to this typical behavior, we report herein that it is possible to promote the scission of the C-S bond of refractory dibenzothiophene by co?feeding the above compounds during hydropurification over a conventional Ni-MoS2/Al2O3 catalyst. Particularly, we prove that at temperatures between 240 and 300°C and concentrations of dibenzothiophene between 1.0 and 3.7 wt.%, the desulfurization of dibenzothiophene is promoted by increasing its conversion up to 370% when either naphthalene, indole, or quinoline are co-fed to the reaction system. The work highlights the following: (i) lower temperatures and higher concentrations of the sulfur heterocycle enhanced the cleavage of the C-S bond from dibenzothiophene; (ii) it is possible to promote hydropurification reactions regardless of the nature of the of co-reactants; namely: a fused aromatic ring -naphthalene-, or a fused nitrogen heterocycle with a lone pair belonging to the pi-system -quinoline- or not -indole-.<br><p><a></a></p>

Practicum activities in higher education especially in State Polytechnic of Malang are generally carried out in a laboratory and based on a predetermined schedule. In the practicum activities are usually used equipment and practical materials borrowed by students from cabinets or warehouses for storage of tools and materials. In addition, in the laboratory where the practicum is carried out there are equipment and personal belongings belonging to students or teachers. From the experience that has happened, some campus-owned lab equipment and materials have been damaged and lost, or the personal property of students or teachers who have been left behind and even lost. Monitoring and recording using ordinary cameras has a disadvantage, that is, we cannot adjust the recording schedule that changes every day based on the space usage schedule. And record data is still one part or not grouped based on space usage schedule. Therefore, it is necessary to make a system that can monitor and record the process of laboratory practicum activities based on space usage schedule. In this study a system will be made using the embeded Raspberry Pi system and a camera module with MySQL as the database, this system is designed and created so that it can be used to record the laboratory practicum activities based on the space usage schedule in the database

Thiazolidinedione (TZD) drugs (Takeda Pharmaceuticals and Metabolic Solutions Development Company) targeting inhibition of the mitochondrial pyruvate carrier (MPC) are currently being tested in clinical trials to prevent progression into mild cognitive impairment of Alzheimer's disease (AD) or in the pipeline to prevent neurodegeneration in Parkinson's disease (PD). These have Ki values in the µM range. This study was focused on identifying candidate drug precursors of the natural cinnamic acid products that might have good bioavailability in the nM ranges forming covalent thiol bonds with targets. In silico protein homology modeling and ligand docking has demonstrated that binding cysteine residues within the transport channel is a key part of the inhibitory mechanism. These are covalent thiohemiacetal bonds with the alpha-carbon, carboxylate group, off a phenol ring. Like the classic MPC inhibitors, these natural derivatives of hydroxycinnamic acid have a conjugated pi-system used to form thiol bonds with the cysteine residue via Michael addition.

This article presents the development of a distributed fault diagnosis and monitoring system whose remote nodes are responsible for data collection and distributed analysis to identify problems that could lead to critical faults in industrial processes or systems. The developed intelligent remote node was implemented with MCU LPCXpresso54114 connected to a ZigBee protocol wireless sensor network through XBee communication module. The gateway node is a Raspberrry PI with HTTP communication and JSON format to the PI System industrial monitoring system database. Motor Current Signature Analysis (MCSA) was implemented and validated to identify interturn faults of induction motors. The developed platform is a tool to perform comparison and validation of analysis techniques, indicators, and fault classification, because there are different combinations that can be applied to improve diagnosis reliability, fault observability, differentiation between fault conditions, classification accuracy, tolerance to transients, sensitivity, among others.

The novel copolymerization polyimide (PI) hollow fibers (HFs) of 4,4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) containing –CF3 groups were prepared and investigated through both simulation and experiment. To demonstrate the alteration attributable to the introduction of fluoromonomers, the condensed states of pyromellitic dianhydride (PMDA)/4,4′-oxybisbenzenamine (ODA), PMDA/6FDA/ODA, and 6FDA/ODA PI were constructed by Material Studio, and we simulated the mobility of molecular chain, free volume fraction, and O2/N2 dissolution–diffusion process. The molecular dynamics simulation results demonstrated that the properties of the copolymerized PI system with 6FDA were significantly improved, while the selectivity remained almost unchanged. Then, the films of copolymerized PI and HFs were prepared by the two-step method, and O2/N2 permeability of the PI copolymer films was characterized, indicating that although the gas permeation performance was greatly improved, the selectivity was not so satisfactory. However, the selection factor increased heavily after polydimethylsiloxane coating.