In principle, the ratio (Φ) of the maximum quantum efficiencies for electroluminescence (EL) to photoluminescence (PL) can be expected to approach unity, if the exciton (bound electron–hole pair) ...generated from the recombination of injected electrons and holes in OLEDs has a sufficiently weak binding energy. However, seldom are examples of Φ > 25% reported in OLEDs because of the strongly bound excitons for most organic semiconductors in nature. Here, a twisting donor–acceptor triphenylamine‐thiadiazol molecule (TPA‐NZP) exhibits fluorescent emission through a hybridized local and charge‐transfer excited state (HLCT), which is demonstrated from both fluorescent solvatochromic experiment and quantum chemical calculations. The HLCT state possesses two combined and compatible characteristics: a large transition moment from a local excited (LE) state and a weakly bound exciton from a charge transfer (CT) state. The former contributes to a high‐efficiency radiation of fluorescence, while the latter is responsible for the generation of a high fraction of singlet excitons. Using TPA‐NZP as the light‐emitting layer in an OLED, high Φ values of 93% (at low brightness) and 50% (at high brightness) are achieved, reflecting sufficient employment of the excitons in the OLED. Characterization of the EL device shows a saturated deep‐red emission with CIE coordinates of (0.67, 0.32), accompanied by a rather excellent performance with a maximum luminance of 4574 cd m−2 and a maximum external quantum efficiency (ηext) of ∼2.8%. The HLCT state is a new way to realize high‐efficiency of EL devices.
A hybridized local and charge‐transfer state character—identified based on solvatochromic effects, lifetime measurements, and DFT calculations—endows twisting donor–acceptor triphenylamine‐thiadiazol molecules (TPA‐NZP) with a high singlet ratio of nearly 100% in OLEDs. Electroluminescent decay analysis and negative magnetic‐field effects indicate that the reason for the high singlet ratio could be the reverse intersystem crossing (RISC) process in the high‐lying charge transfer (CT)X state
In the matter of the Unity of God which is the base of Divine teachings, different views have been presented by the theologians and philosophers of various inclinations and the Sufis and mystics ...regarding real existence and there is a specific understanding of it in the minds of the public who believe and profess the Unity of God which conforms to the views of the Peripatetic philosophers and theologians. They believe in the plurality of existence and plurality of existents based on the theory of contrast and separation of existents from each other, and believes one of these plural and contrasting existents is God and He is one of many existents, and the cause of all others. Another view believes in a single real and true instance of existence and existents and considers it to be God; however, this view believes that this single existence and existent manifests in the form of many contingents and since the result of this manifestation is the nominal existence of the contingents, their plurality does not damage the aforementioned real unity of existence and existent. In this view, the ignorant from among the Sufis and their elders are in accordance with each other, with the difference that the former limit the existence of God to this level of manifestation as can also be seen in the apparent words of the mystics and this results in the negation of the essence of God; however, the latter group, apart from this level, believe in a level of no condition-no description for His essence but consider that single existence and existent in both levels – be it the level of essence or that of the manifestations – to be necessary; in contrast to the … who, though they believed in the unity of existence, however, they consider existence to be necessary in only level and contingent in the other. In another view, which has been attributed to the transcendental inclination, existence is considered principal and real only in the Necessary Being and is, therefore one; however, in contingent beings, quiddity has been considered as principal and it is clear that quiddities are plural and various. Therefore, in this view, existence is one and is only God; however, existents include both God as well as quiddities and contingents and ultimately, in the views of the great mystics and transcendental philosophers, existence and existents, despite their real plurality, have been described as one; like a person who stands in front of multiple mirrors, in which case, man and also humanity, is plural; but since all those reflections are that same one person, they are one despite their plurality. According to this view, contingent existents are reflections, shadows, and rays of the existence of God in the world and are real and true; in contrast to the view of the Sufi scholars in which contingent existents are nominal. The aforementioned views, except the last, somehow mix polytheism regarding the real existence because in all of them limitations have been considered for God and this necessitates that God is one according to numeric unity; as is indicated by Imam Ali (peace be on him) in the sermon regarding Unity of God at the beginning of Nahjul Balagha: one who has limited Him has numbered Him (Nahjul Balagha, 1980: 40). In this case, God would not be alone and one and other existents – the contingent beings – stand beside Him; whereas lexically, tawhid means unique and singular and God is one in essence, i.e. in existence as well as attributes and actions and contingent beings are rays of His existence just as their attributes and actions are manifestations of His attributes and actions because attributes and actions follow existence and are secondary to it. Therefore, this pure and free-from-all-types-of-polytheism monotheism regarding the real existence must be sought among the monotheistic views of the great mystics and transcendental philosophers and this is Mulla Sadra’s ultimate view and can be concluded from all the discussions in The Transcendent Philosophy of the Four Journeys of the Intellect – even though in the discussion of cause and effect (vol. 2) he has chosen the view of the Sufi scholars (Mulla Sadra, 1981, 2: 292), in another period – probably under the influence of his teacher Mirdamad – he believed the view attributed to the transcendental inclination. This study includes three main topics: The different views regarding Unity of God, the criterion of attaining purity from polytheism, A critical study of the monotheistic views of the philosophers in contrast to the mystics.
Single crystalline zero-dimensional (0D) organic-inorganic hybrid materials with perfect host-guest structures have been developed as a new generation of highly efficient light emitters. Here we ...report a series of lead-free organic metal halide hybrids with a 0D structure, (C
N
H
X)
SnX
(X = Br, I) and (C
NH
)
SbX
(X = Cl), in which the individual metal halide octahedra (SnX
) and quadrangular pyramids (SbX
) are completely isolated from each other and surrounded by the organic ligands C
N
H
X
and C
NH
, respectively. The isolation of the photoactive metal halide species by the wide band gap organic ligands leads to no interaction or electronic band formation between the metal halide species, allowing the bulk materials to exhibit the intrinsic properties of the individual metal halide species. These 0D organic metal halide hybrids can also be considered as perfect host-guest systems, with the metal halide species periodically doped in the wide band gap matrix. Highly luminescent, strongly Stokes shifted broadband emissions with photoluminescence quantum efficiencies (PLQEs) of close to unity were realized, as a result of excited state structural reorganization of the individual metal halide species. Our discovery of highly luminescent single crystalline 0D organic-inorganic hybrid materials as perfect host-guest systems opens up a new paradigm in functional materials design.
•DNS of turbulent Bunsen flames at various non-ambient pressure and Lewis numbers (Le) conditions.•Interplay of Darrieus–Landau and thermo-diffusive instability with pressure and Le ...variation.•Analysis of flame morphology in terms of skewness and kurtosis of mean and Gaussian curvatures PDF.•Quantification of excess kurtosis as a marker to distinguish both instabilities.•Influence of pressure and Le on the fractal parameters of Bunsen flames.
The instantaneous flame front structure of high pressure turbulent premixed Bunsen flames has been analyzed for a wide range of characteristic Lewis numbers using a new Direct Numerical Simulation (DNS) database. High pressure turbulent premixed flames of lean-light fuels are likely to feature both thermo-diffusive and Darrieus–Landau instabilities. As the effects of these instabilities are eclipsed by intense turbulence, the present analysis focuses on flames located at the border of the wrinkled and corrugated flamelets regimes. The flame morphology has been characterized by the skewness and kurtosis of the probability density function (PDF) profiles of the mean and Gaussian curvatures. While skewness alone is not sufficient as a marker to distinguish between thermo-diffusive and Darrieus–Landau instabilities, it has been found that excess kurtosis of Gaussian curvature possibly can be used to distinguish between both instabilities. Further, the inner cut-off length and the fractal dimension have been computed for characterization of flame scales and for parameterization of wrinkling factor models. It has been observed that increasing pressure and decreasing Lewis number give rise to flame instabilities which results in an increased fractal dimension and a decreased inner cut-off scale. For high pressure flames with Lewis numbers around unity, the inner cut-off scale scales very well with the critical wavelength for flame instabilities determined from the theoretical analysis by Matalon and Matkowsky (1982). For small sub-unity Lewis numbers, the flames become unconditionally unstable and the critical wavelength loses its meaning, while the inner cut-off scales continues to decrease with Lewis number and the fractal dimension continues to increase up to a limit of about 7/3. The present findings are in excellent agreement with experimental observations from literature and theoretical analysis of flame instabilities.
The research paper titled "Maghreb Unity Struggle" aims to introduce the role played by the Algerian popular resistance in unifying armed efforts against French colonialism. It attempts to encourage ...Maghreb countries, particularly Tunisia and Morocco, to engage in this struggle to hinder French expansion and ultimately end its presence. Additionally, Sufi paths and religious leaders sought to document connections between the Arab peoples of the Maghreb, including their leadership, in order to unify the resistance and warn against the dangers of dealing with colonialism and its pillars. This effort has made a significant impact on fostering unity within various Maghreb communities due to the immense respect it garnered among the people, becoming deeply ingrained in Maghrebi society as a protective fortress for identity elements, especially Islam and Arabic. The joint struggle evolved significantly, particularly after the imposition of French protection on Tunisia in 1881, Italy's occupation of Libya in 1911, and the imposition of French and Spanish protection on Morocco in 1912. This perilous development prompted Maghreb elites, especially the youth movement, to strive for unity in various committees and organizations. They sought to establish connections with international entities hostile to the colonial powers (France, Britain), especially Germany and the Ottoman Empire. This aimed to elevate the unity movement from demanding political reforms to aspiring for freedom and liberation, capitalizing on the international situation during World War I (1914-1918).
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Perovskite nanoplatelets (NPLs), as a promising material to achieve pure blue emission, have attracted significant attention in high gamut displays. However, the high ...surface-to-volume ratio and the loosely connected ligands of NPLs make them susceptible to degradation from light, air and heat. As a result, NPLs often exhibit low photoluminescence (PL) intensity and instability. Here, an Mn-ligand passivation strategy is proposed, in which Mn-doped DMAPbBr3 is used as a precursor. During the perovskite transformation, Mn2+ ions migrate from the lattice of DMAPbBr3 to the surface of CsPbBr3 NPLs, which have strong binding forces with ligands. The final products Mn-CsPbBr3 (M−CPB) NPLs are then acquired by the ligand-induced ripening growth process, which not only exhibit pure blue emission with narrow full width at half maximum (FWHM), but also possess near-unity PL quantum yields (QYs). Besides, M−CPB NPLs show excellent stability due to the strong Mn-ligand passivation layer. Based on the new growth mechanism discovery, the reaction time can be shortened to several minutes by heating. The innovative growth model proposed in this work will provide a paradigm for designing and optimizing future synthesis schemes.
Meshfree methods based on radial basis function (RBF) approximation are becoming widely used for solving PDE problems. They are flexible with respect to the problem geometry and highly accurate. ...A disadvantage of these methods is that the linear system to be solved becomes dense for globally supported RBFs. A remedy is to introduce localisation techniques such as partition of unity. RBF partition of unity methods (RBF–PUM) allow for a significant sparsification of the linear system and lower the computational effort. In this work we apply a global RBF method as well as RBF–PUM to problems in option pricing. We consider one- and two-dimensional vanilla options. In order to price American options we employ a penalty approach. A penalty term, suitable for American multi-asset call options, has been designed. RBF–PUM is shown to be competitive compared with a finite difference method and a global RBF method. It is as accurate as the global RBF method, but significantly faster. The results for RBF–PUM look promising for extension to higher-dimensional problems.
Holiness and Unity Carter, David
Holiness,
10/2022, Letnik:
7, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Drawing on the International Methodist – Catholic report on
, this article identifies
as both a divine attribute and as a Christian imperative, inextricably linked with the unity of Christians and of ...humanity. For humanity to be in the image and likeness of this holy God implies a participation in God’s holiness. Because human life is inescapably social, it implies that this holiness must be expressed in social interaction. For the life of the Christian Church to reflect the holiness of God requires a commitment to unity and actions that echo that commitment. This paper traces the biblical basis of the Judaeo-Christian belief in the holiness of God. It goes on to examine the obstacles and opportunities for Christian unity, particularly between the churches of the Wesleyan tradition and the Church of Rome.
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