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The rational design of crystalline clusters with adjustable compositions and dimensions is highly sought after but quite challenging as it is important to understand their structural evolution processes and to systematically establish structure-property relationships. Herein, a family of organotin-based sulfidometalate supertetrahedral clusters has been prepared via mixed metal and organotin strategies at low temperatures (60-120 °C). By engineering the metal composition, we can effectively control the size of the clusters, which ranges from 8 to 35, accompanied by variable configurations: P1-[(RSn)4M4S13], T3-[(RSn)4In4M2S16] (R = nbutyl-Bu and phenyl-Ph; M = Cd, Zn, and Mn), T4-[(BuSn)4In13Cu3S31], truncated P2, viz. TP2-[(BuSn)6In10Cu6S31], and even T5-[(BuSn)4In22Zn6Cu3S52], all of which are the largest organometallic supertetrahedral clusters known to date. Of note, the arylstannane approach plays a critical role in regulating the peripheral ligands and further enriching geometric structures of the supertetrahedral clusters. This is demonstrated by the formation of tin-oxysulfide clusters, such as T3-[(RSn)4Sn6O4S16] (R = Bu, Ph, and benzyl = Be) and its variants, truncated T3, viz., TT3-[(BuSn)6Sn3O4S13] and augmented T3, viz., T3-[(Bu3SnS)4Sn6O4S16]. Especially, two extraordinary truncated clusters break the tetrahedral symmetry observed in typical supertetrahedral clusters, further substantiating the advantages offered by the arylstannane approach in expanding cluster chemistry. These organometallic supertetrahedral clusters are highly soluble and stable in common solvents. Additionally, they have tunable third-order nonlinear optical behaviors by controlling the size, heterometallic combination, organic modification, and intercluster interaction.
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Two novel two-dimensional metal-organic frameworks (2D MOFs), 2D-M2 TCPE (M=Co or Ni, TCPE=1,1,2,2-tetra(4-carboxylphenyl)ethylene), which are composed of staggered (4,4)-grid layers based on paddlewheel-shaped dimers, serve as heterogeneous photocatalysts for efficient reduction of CO2 to CO. During the visible-light-driven catalysis, these structures undergo in situ exfoliation to form nanosheets, which exhibit excellent stability and improved catalytic activity. The exfoliated 2D-M2 TCPE nanosheets display a high CO evolution rate of 4174â µmol g-1 h-1 and high selectivity of 97.3 % for M=Co and Ni, and thus are superior to most reported MOFs. The performance differences and photocatalytic mechanisms have been studied with theoretical calculations and photoelectric experiments. This study provides new insight for the controllable synthesis of effective crystalline photocatalysts based on structural and morphological coregulation.
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Four isomorphic P2 chalcogenide clusters named [Sn11In9Cu6S44]·11(H+DBU) (1) (DBU = 1,8-diazabicyclo[5.4.0] undec-7-ene), [Sn10In10Cu6Se44]·6(H22+DMAPA)·2(DMAPA)·9EG (2) (DMAPA = 3-dimethylaminopropylamine, EG = ethylene glycol), [Sn10In10Cu6S40O4]·6[H22+PMDETA]·10EG (3) (PMDETA = pentamethyldiethylenetriamine), [Sn10Ga10Cu6S40O4]·6(H22+DMAPA)·7EG (4) have been isolated via organotin precursor and mixed-metal strategy. These clusters exhibit excellent solubility in organic solvents. The continuous-regulation of optical band and optical limiting performance have been realized through precise controlled substituting engineering of cationic and anionic elements.
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Global warming and extreme weather have increased most people's awareness of the problem of environmental destruction. In the domain of sustainable development, environmental governance has received considerable scholarly attention. However, protecting and improving the environment requires not only substantial capital investment but also cooperation among stakeholders. Therefore, based on the network structure of stakeholders, the best-worst method (BWM) and modified Vlsekriterijumska Optimizacija I Kompromisno Resenje method were combined to form an environmental co-governance assessment framework that can be used to evaluate the effects of various policies and identify strategies for further improvement through data analysis (henceforth the BWM-mV model). This mechanism is not only useful for evaluating the effectiveness of environmental governance policies but also for generating suggestions to enhance these policies. Hence, the BWM-mV model is particularly suitable for local governments with limited resources in time, money, or labor. Pingxiang City Government is currently subject to such limitations and was therefore selected as the subject of an empirical case study. The results of this study revealed that the aspects (i.e., criteria) the Pingxiang City Government should urgently improve on pertain to a high-quality information communication platform (C13) and smooth joint decision-making by stakeholders (C24).
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Conservación de los Recursos Naturales , Política Ambiental , Ciudades , Humanos , Desarrollo SostenibleRESUMEN
Two crystalline salts, T3-SnOX-MTN (X = S/Se, MTN denotes a defined zeotype), both spatially assembled in an MTN net, have been fabricated. This was achieved by interlinking the isolated tin-oxychalcogenide tetrahedrally shaped clusters of T3-[Sn10O8X16]8- (X = S/Se) through coulombic interactions with protonated organic amine templates. T3-SnOX-MTN (X = S/Se), with 74.1/76.5 Å cubic unit-cell axial-lengths, have a proton-conductivity of over 10-3 S cm-1 under 98% relative humidity at 50 °C.
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Because of the high efficiency and mild reaction conditions, electrocatalytic CO2 reduction (ECR) has attracted significant attention in recent years. However, the specific mechanism of the formation of the two-electron production (CO or HCOOH) in this reaction is still unclear. Herein, with density functional theory calculation and experimental manipulation, the specific mechanism of the selective two-electron reduction of CO2 has been systematically investigated, employing the polyphenolate-substituted metalloporphyrinic frameworks, ZrPP-1-M (M = Fe, Co, Ni, Cu, and Zn), as model catalysts. Experimental observations and theoretical calculations discovered that ZrPP-1-Co is a more favorable catalyst for ECR among them. Compared with the formation of HCOOH, electroreduction of CO2 into CO has more beneficial thermodynamic and kinetic routes with ZrPP-1-Co as a catalyst. After introducing the r-GO for improving the conductivity, the Faradaic efficiency for CO formation is 82.4% at -0.6 v (vs RHE).
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Most of the baby boomers born after the Second World War (WWII) have passed the age of 65, meaning they have gradually lost their social functions and positions, and are facing the need for care. In Taiwan, the lack of a long-term care mechanism is having a certain degree of impact on society as a whole, and thus, it is important to have a mechanism to take care of the elderly. In order to make this system sustainable, sufficient funds and continuous improvement are important factors. In the past, in order to avoid the illegal transfer of benefits, the social welfare mechanism avoided the use of for-profit organizations. However, as the economic environment declines, the role of for-profit organizations should be considered. This study defines the long-term ageing health care system using five major dimensions and 20 criteria. The DANP-mV model was used to analyze Taiwan's current system and identify problems, and then to develop a continuous improvement strategy from the perspective of the source of the problem in order to improve long-term ageing health care.
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Cuidados a Largo Plazo/métodos , Anciano , Anciano de 80 o más Años , Humanos , Modelos Teóricos , TaiwánRESUMEN
We report, herein, a diamond-like oxysulfide framework, 3D-T4-SnOS, based on the largest supertetrahedral cluster of Sn4+ ions, i.e. [Sn20O10S34]. The framework remains intact in aqueous solution over a pH range between 1 and 14, and has a narrower optical bandgap, red-shifted fluorescence emission, and an enhanced photoelectric response compared to that of the smaller version, 2D-T3-SnOS, which has a building unit of supertetrahedral [Sn10O4S20].
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We report herein a series of lanthanide sulfate-carboxylpyrazolate frameworks based on double cuboid cavities that are highly hot-water stable, and have room-temperature proton conductivity of over 10-3 S cm-1 at 97% relative humidity without any appreciable loss of performance for at least three recycling times, ranking among the best lanthanide-based coordination frameworks.
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Climate change-related anomalies have increased public concern regarding environmental protection. This has opened newer rural development avenues. In this regard, livability of villages is crucial; it can be evaluated based on the villagers' quality of life (QoL). The WHOQOL-BREF, a comprehensive cross-cultural and cross-disciplinary scale proposed by the World Health Organization to assess QoL, has aided in assessing and improving QoL in different regions. However, the factors of this instrument are mutually influential, necessitating an improvement strategy considering the entire system. This problem may be resolved using the DANP-mV model. However, the traditional DANP-mV model includes many items and responding to all of them is difficult for experts. Therefore, by using the case of Xingshisi Village in China, this study proposed a modified DANP-mV model to provide additional suggestions for systematic improvement of the QoL and livability in the village. Xingshisi is a model village built according to an aspirational benchmark; however, different from the traditional definition of a benchmark, this village exhibits room for improvement. Although the modified model reduces the number of questions from 650 to 168, its effect remains similar to that of the traditional model. Moreover, in the modified model, physical capacity (D1) presented the largest dimensional gap. The interaction among the factors indicated that considering the effect of the environment (D4) and developing a systematic improvement strategy are necessary to improve the livability of villages facing limited resources.
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Calidad de Vida , Población Rural , Adulto , China , Conservación de los Recursos Naturales , Investigación Empírica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Organización Mundial de la SaludRESUMEN
With globalization, the notion of "creative city" has become a core concept of many cities in the world development policies, with real properties being upgraded or used to change, renewal is being conducted, and creative industries are emerging. This trend has reached its peak in the past decade, with different forms and scales gathering global development momentum among the creative communities to promote the development of creative economies. In recent years, however, there was still skepticism about the sustainability of the current creative communities. Many scholars have pointed out that signs of unsustainability have begun to appear in many creative communities. To overcome these obstacles, the development of rational and highly effective improvement strategy requires a dynamic thinking process. Therefore, this study employs the DEMATEL-based ANP with modified VIKOR (D-DANP-mV) model in presenting an assessment framework for the sustainability of creative communities. This system is used to assess the sustainability of current creative communities and determine how to solve their problems. Thus, continuous and systemic improvement strategies can be developed to achieve the aim of sustainable development. Two creative communities in Taiwan, Taichung Cultural and Creative Industries Park (TCCIP), and Shen-Ji New Village (SJNV), are used as case studies in this study. Based on the concept of systematic improvement from fundamental issues, the results indicate that the improvement priorities can be determined by applying the D-DANP-mV model. This approach is different from those found by a conventional method with the hypothesis of independent criteria (e.g., diversification of creative talents in TCCIP), and cannot use for performance improvement (e.g., only can be used for ranking and selection among alternatives). Considering these points, unreasonable premises, biased errors, and lack of some real application functions in the process of resource allocation could be more efficient improvement strategies generated in this proposed model.