Cyclic Complexes Research Articles

Pyrazolate vs. phenylethynide: direct exchange of the anionic bridging ligand in a cyclic trinuclear silver complex.

Cyclic trinuclear Ag(I) pyrazolate interacts with phenylacetylene forming a mix-ligand complex in which one pyrazolate ligand is changed to phenylethynide. The CC- fragment coordinates only to two silver(I) atoms via one carbon atom demonstrating unique μ2-η1 σ-coordination with close Ag-C bond lengths and Ag-C-C angles. The complex exhibits blue emission under UV irradiation.

Structural and thermochemical investigation of 1,3-bis(λ4-boraneyl)-1λ4,3λ4-imidazolidine adduct for chemical hydrogen storage.

The structure, thermochemical properties and reaction pathways of a cyclic amine diborane complex (1,3-bis(λ4-boraneyl)-1λ4,3λ4-imidazolidine) were investigated using quantum chemical calculations. Structural and thermochemical analysis revealed that the simultaneous and spontaneous elimination of both hydrogen molecules from this complex is predicted to occur under thermoneutral conditions. This observation is further supported by the investigation of the BH3-catalysed dehydrogenation pathway. The calculated thermochemical parameters indicate that the energy requirements for hydrogen release from this complex are minimal, suggesting efficient hydrogen release capability under suitable conditions. Additionally, the activation barriers, ∼75 and ∼20 kJ mol-1 for the first and second dihydrogen release from the catalysed dehydrogenation reactions of this compound exhibit moderate kinetics, confirmed by kinetic studies. These findings and the ability of the system to easily release two molecules of dihydrogen emphasize the potential of 1,3-bis(λ4-boraneyl)-1λ4,3λ4-imidazolidine as a highly effective hydrogen storage material.

Dinitrogen activation by a titanium hydride complex supported by 2-butene ligand

The activation of dinitrogen by a titanium hydride complex with two bridging hydrides located between metal Ti and Li was investigated.

Complex Motion Behavior and Synchronization Analysis of Heterogeneous Neural Network

Complex Motion Behavior and Synchronization Analysis of Heterogeneous Neural Network

Complex rhythm and synchronization of half-center oscillators under electromagnetic induction

<p>Half-center oscillators are typical small circuits that are crucial for understanding CPG. The complex rhythms of CPG are closely related to certain diseases, such as epilepsy. This paper considered the influence of electromagnetic induction on the discharge mode of the half-center oscillators. First, we analyzed the response of individual firing neuron rhythms to electromagnetic induction when the slow-variable parameters vary. We also discussed the changes in the dynamic bifurcation structure when the intensity of electromagnetic induction varies. Furthermore, we determined the effects of mutually inhibitory and self-inhibitory synaptic parameters on the firing rhythm of the half-center oscillators. The different responses induced by electromagnetic induction interventions, showed that mutually inhibitory synapses modulate the firing rhythm weakly and self-inhibition synapses have a significant impact on firing rhythm. Finally, with the change of synaptic parameter values, the combined effects of autapse and mutually inhibitory synapses on the discharge rhythm of half-center oscillators were analyzed in symmetric and asymmetric autapse modes. It was found that the synchronous state of the half-center oscillators had a more robust electromagnetic induction response than the asynchronous state.</p>

Development of an on-machine surface measurement system for an ultra-precision five-axis machine

Ever-increasing demand for complex freeform surfaces machined by ultra-precision five-axis machines necessitates efficient on-machine surface measurement (OMSM) systems. While OMSM offers significant advantages in metrology efficiency and machining accuracy, integrating it with these machines presents a challenge due to complex data synchronization and processing. This paper addresses this challenge by proposing a dedicated controller for synchronized acquisition of sensor measurement data and machine coordinate data. Additionally, a straightforward sensor alignment method is presented. The effectiveness of the proposed OMSM system is demonstrated through successful 2D and 3D measurements, significantly streamlining the traditional time-consuming offline coordinate measuring machine (CMM) and optical profilometer measurements.

Generating automated test case from sequence diagram using Pre-order Traversal

Automated test case generation is important in software testing to evaluate developed software. The testing process requires test cases that can be based on Software Requirements Specification (SRS) and Software Design Document (SDD). One of UML diagrams included in the previous documentations is sequence diagram. This research proposed a modified pre-order algorithm that can generate test cases automatically from sequence diagrams. Our manual cyclomatic complexity evaluation showed that our method produced accurate test cases based on the sequence of messages in the sequence diagram. This result justifies that the generated test cases match the relevant sequence diagram.

Rotational spectroscopy of 2,4,6-cycloheptatriene-1-carbonitrile: facilitating the search for complex cyclic molecules in the ISM.

The recent astronomical observations of the simplest aromatic nitrile benzonitrile, c-C6H5CN, followed by a five-membered and a bicyclic CN-functionalized ring in TMC-1 have provided a significant impetus to the field for searches of cyclic complex organic molecules in space. One such example is 2,4,6-cycloheptatriene-1-carbonitrile, a seven-membered ring with a -CN group attached to the sp3-hybridized carbon atom. With a permanent electric dipole moment of 4.3 D, this molecule is an excellent candidate for laboratory rotational spectroscopy. In this study, experiments were performed in the 2-8 GHz, 18-26 GHz, and 75-110 GHz frequency ranges in a supersonic expansion setup and a room temperature flow cell setup. The measurements across the broad frequency range of 2-110 GHz have enabled the identification and assignment of the vibronic ground state, singly substituted rare-atom isotopologues, and vibrationally excited states. Here, we report the precise determination of the rotational constants, quartic centrifugal distortion constants, nitrogen nuclear quadrupole coupling constants, as well as molecular structure in its vibronic ground state. The comprehensive rotational spectroscopy study of this molecule, covering a large frequency range, forms the basis for its future astronomical detection and thus for extending the pool of detected complex cyclic molecules.

Magnetized Seeds and Structured Water: Effects on Resilience of Velvet Bean Seedlings (Mucuna pruriens) under Deficit Irrigation

A custom-built water generator supplied structured water (SW) for applying the deficit irrigation treatments to velvet bean plants (Mucuns pruriens). The objectives of the study were to 1) determine the effects of magnetized seed treatment on velvet bean plants, 2) determine the effects of magnetized and hydroxylated water treatments on velvet bean plants, and 4) determine the effects of deficit irrigation, using three soil moisture levels, on velvet bean plants. The optimal water-saving treatment was magnetized seeds plus 10 MT + HWT. This treatment had a 226% increase in transpiration and a 22% increase in water vapor concentration in the intercellular airspace for the low soil moisture watering schedule. The three study factors in the optimal seed and water treatment had a synchronistic effect for enhancing metabolic efficiency by increasing whole plant WUE by 87% and carbon assimilation efficiency by 66% in the low soil moisture schedule. Plants irrigated with SW water and grown from magnetized seeds had enhanced resilience to high water stress conditions by maintaining adequate levels of biologically structured water. The rapid deactivation of a suite of highly interconnected defense activities in the optimal seed and water treatments implies that the plants exhibit macroscopic coherence properties. Coherence at the macroscopic level resulted in complex synchronization between metabolic efficiency, plant health, and deactivation of a suite of regulatory defenses in plants exposed to high water stress.

Implementasi Sistem Pakar Android untuk Deteksi Penyakit Tanaman Coklat dengan Metode Certainty Factor

This research focuses on issues within the agricultural sector, specifically in cocoa farming. The associated problem is the lack of agricultural extension workers, which results in farmers' limited understanding of cocoa plant diseases and their management. As a consequence, disease identification in cocoa plants has traditionally relied on mere estimates, often proving inaccurate and inefficient in taking appropriate actions. The primary objective of this research is to design and develop an Android-based application utilizing the Certainty Factor method for diagnosing diseases in cocoa plants. The application is envisioned to function as an intelligent consultant for providing disease diagnoses in cocoa plants. The research employs the Research and Development methodology, gathering data from both primary and secondary sources through observations and interviews. The application is tested using both whitebox and blackbox methodologies. Whitebox testing results demonstrate that the system can operate effectively, as indicated by calculations of V(G) and Cyclomatic Complexity (CC). Blackbox testing, conducted with sample tests, also indicates that the system functions as expected and efficiently. In conclusion, the system developed in this research can significantly assist users, particularly farmers, in diagnosing diseases in cocoa plants. The expert system for diagnosing cocoa plant diseases can be relied upon and operates effectively.

Reaktivität von [Cp*Fe(η5‐As5)] gegenüber Carbenen, Silylenen und Germylenen

AbstractDas Reaktionsverhalten von [Cp*Fe(η5‐As5)] (I) (Cp*=C5Me5) gegenüber Carbenen und ihren schwereren Analoga wurde untersucht. Die Reaktion von I mit NHCs (NHCs=N‐heterocyclische Carbene) gibt die ersten Substitutionsprodukte von Polyarsen‐Ligandkomplexen mittels NHCs [Cp*Fe(η4‐As5NHC)] (1 a: NHC=IMe=1,3,4,5‐Tetramethylimidazolin‐2‐yliden, 1 b: NHC=IMes=1,3‐Bis(2,4,6‐trimethylphenyl)‐imidazolin‐2‐yliden). Im Gegensatz dazu führt die Reaktion von I mit EtCAAC (EtCAAC=2,6‐Diisopropylphenyl)‐4,4‐diethyl‐2,2‐dimethyl‐pyrrolidin‐5‐yliden) zu einer Fragmentierung und Bildung einer neuartigen As6‐sägebockartigen Verbindung [As2(AsEtCAAC)4] (2). Die Reaktion von (LE)2 (L=PhC(NtBu)2; E=Si, Ge) mit I resultiert in einer Umlagerung und einer Insertion von LE‐Fragmenten, was zur Bildung einzigartiger silizium‐ (4: [Cp*Fe(η4‐As4SiL)], 5 a: [Cp*Fe(η4‐As6SiL)) und germanium‐haltiger (5 b: [Cp*Fe(η4‐As6GeL)) cyclischer Polyarsen‐Ligandkomplexe führt.

Reactivity of [Cp*Fe(η5 -As5 )] towards Carbenes, Silylenes and Germylenes.

The reaction behavior of [Cp*Fe(η5 -As5 )] (I) (Cp*=C5 Me5 ) towards carbenes and their heavier analogs was investigated. The reaction of I with NHCs (NHCs=N-heterocyclic carbenes) results in the first substitution products of polyarsenic ligand complexes by NHCs [Cp*Fe(η4 -As5 NHC)] (1 a: NHC=IMe=1,3,4,5-tetramethylimidazolin-2-ylidene, 1 b: NHC=IMes=1,3-bis(2,4,6-trimethylphenyl)-imidazolin-2-ylidene). In contrast, the reaction of I with Et CAAC (Et CAAC=2,6-diisopropylphenyl)-4,4-diethyl-2,2-dimethyl-pyrrolidin-5-ylidene) leads to a fragmentation and the formation of an unprecedented As6 -sawhorse-type compound [As2 (AsEt CAAC)4 ] (2). The reaction of (LE)2 (L=PhC(Nt Bu)2 ; E=Si, Ge) with I resulted in a rearrangement and an insertion of LE fragments, forming unique silicon- (4: [Cp*Fe(η4 -As4 SiL)], 5 a: [Cp*Fe(η4 -As6 SiL)) and germanium-containing (5 b: [Cp*Fe(η4 -As6 GeL)) cyclic polyarsenic ligand complexes.

All-fiber frequency agile triple-frequency comb light source

Tricomb spectroscopy unveils a new dimension to standard linear and nonlinear spectroscopic analysis, offering the possibility to reveal the almost real-time evolution of complex systems with unprecedented accuracy. Current triple comb configurations are based on the use of mode-locked lasers, which impose constraints on the comb parameters, and require complex electronic synchronization, thus limiting potential applications. In this paper, we present the experimental demonstration of a new type of all-fiber, self-phase-locked, frequency-agile tri-comb light source. It is based on the nonlinear spectral broadening of three electro-optic modulator-based frequency combs in a three-core fiber. The exploitation of spatial multiplexing of light in optical fibers offers new possibilities to generate broadband-frequency combs that are highly coherent with each other. After characterizing the stability of the source and performing several dual-comb test measurements, we revealed the high mutual coherence between the three combs through the demonstration of a 2-D pump-probe four-wave mixing spectroscopy experiment.

IDE vs. pen-and-paper showdown - Performance and perceptions of testing first-year IT students’ programming skills

This study analysed first-year IT students' performance and perceptions of using Integrated Development Environment (IDE) versus pen and paper (P&P) based programming testing methods. 68 participants completed two programming tests using both testing methods, and the results were evaluated on complexity, quality and other criteria. No significant difference was observed in the average scores between the two test methods. However, IDE testing showed fewer syntax errors and lower cyclomatic complexity, indicating the potential advantages of IDE's error-checking. IDE tests exhibited higher variability in student performance, suggesting varying comfort levels with the test environment. Additionally, a weaker correlation existed between actual and perceived performance in IDE tests, highlighting challenges in self-evaluation within a digital framework. Most students preferred IDE-based testing, citing efficiency, user-friendliness, and real-time feedback. Nonetheless, a minority recognised the value of P&P tests for demonstrating deep syntax understanding. This research enhances our understanding of programming pedagogy and assessment.

An anthraquinone-based Cu(I) cyclic trinuclear complex for photo-catalyzing C-C coupling reactions

An anthraquinone-based Cu(I) cyclic trinuclear complex for photo-catalyzing C-C coupling reactions

General Methods to Synchronize Fractional Discrete Reaction–Diffusion Systems Applied to the Glycolysis Model

Because they are useful for both enabling numerical simulations and containing well-defined physical phenomena, discrete fractional reaction–diffusion models have attracted a great deal of interest from academics. Within the family of fractional reaction–diffusion models, a discrete form is examined in detail in this study. Furthermore, we investigate the complex synchronization dynamics of a suggested discrete master–slave reaction–diffusion system using the accuracy of linear control techniques combined with a fractional discrete Lyapunov approach. This study’s deviation from the behavior of equivalents with integer orders makes it very fascinating. Like the non-local nature inherent in Caputo fractional derivatives, it creates a memory Lyapunov function that is closely linked to the historical background of the system. The investigation provides a strong basis to the theoretical results.

Phosphine oxide donor-based dinuclear rhenium(I) metallocycles

Neutral binuclear metallocycles fac- [{Re(CO)3}2(CA)(L)] (1–2) were obtained using Re2(CO)10, flexible ditopic phosphine oxide donor 9,10-bis(dimethylphosphonomethyl)anthracene/ 9,10-bis(diethylphosphonomethyl)anthracene (L), and chloranilic acid (H2−CA) in mesitylene via one-pot solvothermal methods. The metallocycles were characterized by E.A., FT-IR, ESI-MS and NMR analysis. The solid-state structures of 1–2 were confirmed by X-ray analysis which reveal that the complexes adopt binuclear heteroleptic cyclic architectures. The fac- [Re(CO)3] core-based metallocycles 1–2 are two of the very few examples of phosphine oxide donor (P=O)-based supramolecular coordination cyclic complexes.

An empirical study on software understandability and its dependence on code characteristics

ContextInsufficient code understandability makes software difficult to inspect and maintain and is a primary cause of software development cost. Several source code measures may be used to identify difficult-to-understand code, including well-known ones such as Lines of Code and McCabe’s Cyclomatic Complexity, and novel ones, such as Cognitive Complexity.ObjectiveWe investigate whether and to what extent source code measures, individually or together, are correlated with code understandability.MethodWe carried out an empirical study with students who were asked to carry out realistic maintenance tasks on methods from real-life Open Source Software projects. We collected several data items, including the time needed to correctly complete the maintenance tasks, which we used to quantify method understandability. We investigated the presence of correlations between the collected code measures and code understandability by using several Machine Learning techniques.ResultsWe obtained models of code understandability using one or two code measures. However, the obtained models are not very accurate, the average prediction error being around 30%.ConclusionsBased on our empirical study, it does not appear possible to build an understandability model based on structural code measures alone. Specifically, even the newly introduced Cognitive Complexity measure does not seem able to fulfill the promise of providing substantial improvements over existing measures, at least as far as code understandability prediction is concerned. It seems that, to obtain models of code understandability of acceptable accuracy, process measures should be used, possibly together with new source code measures that are better related to code understandability.

Complexity Synchronization of Organ Networks.

The transdisciplinary nature of science as a whole became evident as the necessity for the complex nature of phenomena to explain social and life science, along with the physical sciences, blossomed into complexity theory and most recently into complexitysynchronization. This science motif is based on the scaling arising from the 1/f-variability in complex dynamic networks and the need for a network of networks to exchange information internally during intra-network dynamics and externally during inter-network dynamics. The measure of complexity adopted herein is the multifractal dimension of the crucial event time series generated by an organ network, and the difference in the multifractal dimensions of two organ networks quantifies the relative complexity between interacting complex networks. Information flows from dynamic networks at a higher level of complexity to those at lower levels of complexity, as summarized in the 'complexity matching effect', and the flow is maximally efficient when the complexities are equal. Herein, we use the scaling of empirical datasets from the brain, cardiovascular and respiratory networks to support the hypothesis that complexity synchronization occurs between scaling indices or equivalently with the matching of the time dependencies of the networks' multifractal dimensions.

Quasi-projective synchronization of memristor-based complex valued recurrent neural network with time-varying delay and mismatched parameters

This article focuses on the quasi-projective synchronization for a class of non-identical memristor-based complex-valued recurrent neural networks (MCVRNNs) with time-varying delays and parameters’ mismatched. Here, the quasi-projective synchronization is presented in two ways based on the Halanay inequality and some useful techniques. Some novel sufficient conditions are firstly derived for quasi-projective synchronization criteria of non-identical memristor-based CVRNNs with time-varying delays and parameters’ mismatched by using the matrix measure method. And then, by using the Lyapunov-Krasovskii functional, another sufficient stabilization condition for quasi-projective synchronization of the concerned model is presented. Finally, two numerical simulation results are given to demonstrate the usefulness and persistence of the proposed methods under some conditions.