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1.
Psychol Res Behav Manag ; 17: 1021-1043, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495089

RESUMO

Purpose: The analysis of the pivotal determinants that impact the progression of inter-team conflict processes in multi-team systems, as well as their underlying mechanisms, serves to explicate the developmental framework of said conflict processes. Methodology: This study adopts a vantage point centered on the evolution of inter-team conflict in multi-team systems, with a specific focus on the sequential progression including "conflict latency → conflict perception → conflict management → conflict outcome → conflict feedback. Results: By transmuting qualitative data into quantitative data through the discernment of inter-conceptual relationships' directionality and quantity, this study distills the key chain of relationships between categories. Employing the explanatory structure model, the developmental mechanism of inter-team conflict processes in multi-team systems is unveiled. Notable sources of conflict include team goal identification, team role multiplicity, inter-team relationships, and team competence. Factors that exert a significant influence on conflict management comprise inter-team conflict types, inter-team relationships, team competence, inter-team heterogeneity, team affiliation, and system goals. Reviewing the genuine motivations underlying conflict management behavior, as well as adopting a lengthier temporal perspective, emerges as a crucial consideration when analyzing the implications of conflict management on both the system and the team for evaluative purposes. Inter-team communication emerges as a pivotal influence on the efficacy of conflict management, which, in turn, is influenced by boundary managers, inter-team heterogeneity, and the inter-team interactive memory system. Conclusion: Through an in-depth analysis of the hierarchical interrelationships among factors that influence conflicts within teams, we have established a model for the conflict development process. This model is instrumental in comprehensively understanding the dynamics of conflict evolution within teams. It serves as a reference point for formulating more precise and effective conflict management strategies. Moreover, this model not only offers practical guidance for resolving conflicts within a multi-team framework but also enhances inter-team collaboration. Therefore, it contributes significantly to achieving the objectives of the multi-team system.

2.
Ultrason Sonochem ; 60: 104746, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31539727

RESUMO

Layered double hydroxide (LDH)-supported Pd nanocatalysts (Pd/LDH-OH) were prepared by ultrasonic-assisted reduction at 30 °C using an ultrasonic bath at a frequency of 25 kHz and an input power of 400 W for 30 min without the addition of any stabilizing reagent or chemical reductant, using LDH with a layered structure and interparticle mesoporosity as the reductant and carrier. This kind of pore structure allows ultrasound waves to spread inside the pore and make ultrasound directly act on the surface hydroxyl groups of LDH, producing highly reductive free radicals (H). The reductive free radicals rapidly reduced Pd2+ to Pd0, forming ultrafine Pd nanoparticles (PdNPs) with a particle size distribution of 1.85 nm-3.45 nm and an average particle size of 2.52 nm. The surface hydroxyl groups were converted to exposed oxygen groups after dissociation of hydrogen radicals, which is beneficial for anchoring and dispersing the resultant PdNPs. The resultant PdNPs were uniformly dispersed on the surface of the LDH carrier. The yield of the Suzuki coupling reaction between 4-bromotoluene and phenylboronic acid catalyzed by Pd/LDH-OH at 60 °C was 95.49% for 5 min and the TOF was 190.98 min-1. After repeated for 5 times, the yield was maintained at 84.59%. The prepared Pd/LDH-OH nanocatalyst and the catalytic system are useful for Suzuki-Miyaura coupling reactions of N- and S-heterocyclic substrates. This provides an efficient and green approach for the preparation of supported nanopalladium catalysts.

3.
IET Nanobiotechnol ; 12(8): 1031-1036, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30964009

RESUMO

The bio-synthesis of palladium nanocubes (PdNCs) was realised using pine needle extract as the reducing agent and cetyl trimethyl ammonium bromide as the capping agent. As an eco-friendly and readily available biomass, pine needle extract avoided the use of highly polluting chemical reducing agents. The growth process of PdNCs was analysed using ultraviolet-vis and Fourier transform infrared spectroscopy. Flavonoids, esters, terpenoids and polyhydric alcohols, which contain reductive groups, were mainly responsible for the transition of Pd2+ ions to PdNCs. The morphology and structure of PdNCs were characterised using transmission electron microscopy (TEM), high-resolution TEM, selected area electron diffraction and X-ray diffraction. It was indicated that the as-prepared PdNCs displayed a relatively high purity and good crystallinity with a face-centred cubic structure and exhibited sizes ranging from 6.11 to 29.51 nm with an average particle size of 11.18 nm. In the methanol electro-oxidation reaction, the PdNCs enclosed by {100} facets exhibited superior electro-catalytic activity to commercial Pd/C, which was rarely reported in other bio-synthesis processes for Pd catalysts. Meanwhile, the PdNCs showed excellent anti-poisoning ability and long-term stability. This study reveals the possibility of preparing shape-controlled PdNCs with a specific structure and excellent electro-catalytic activity.


Assuntos
Química Verde/métodos , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Paládio/química , Extratos Vegetais/química , Catálise , Paládio/metabolismo , Tamanho da Partícula , Extratos Vegetais/metabolismo , Análise Espectral
4.
Zhong Yao Cai ; 33(7): 1042-5, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-21137358

RESUMO

OBJECTIVE: The feasibility of producting flavonoids from callus of Tetrastigma hemsleyanum was investigated through callus induction, proliferation, differentiation and determination of flavonoids. METHODS: The leaves of sterile plantlet, leaves and stems of wild plants were used as explants to induce calluses; The root tuber, the leaves and calluses were selected for the determination of flavonoids. With ethanol as the solvent, the total flavonoids were extracted by ultrasonic and determined by spectrophotometry at 500 nm after stained with NaNO2-Al(NO3) 3. RESULTS: The optimum medium where the calluses were induced was 2/3MS +2.0 mg/L 6-BA +2.0 mg/L NAA; MS +2.0 mg/L 6-BA +2.0 mg/L NAA was the optimum for callus proliferation; for callus root differentiation, the optimum medium was 1/2MS +1.0 mg/L 6-BA +1.0 mg/L NAA. The content of total flavonoids was 31.121 mg/g in root tuber, 12.830 mg/g in leaves while it was up to 18.088 mg/g in calluses. CONCLUSION: The calluses had a high level of total flavonoids, it could produce flavonoids through the calluses induced by Tetrastigma hemsleyanum in a large scale. In that case, the pressing requirement in medical market will be solved.


Assuntos
Flavonoides/análise , Reguladores de Crescimento de Plantas/farmacologia , Plantas Medicinais/crescimento & desenvolvimento , Vitaceae/química , Vitaceae/crescimento & desenvolvimento , Meios de Cultura/química , Flavonoides/isolamento & purificação , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Caules de Planta/química , Caules de Planta/efeitos dos fármacos , Caules de Planta/crescimento & desenvolvimento , Plantas Medicinais/química , Plantas Medicinais/efeitos dos fármacos , Técnicas de Cultura de Tecidos/métodos , Vitaceae/efeitos dos fármacos
5.
Zhongguo Zhong Yao Za Zhi ; 32(10): 893-8, 2007 May.
Artigo em Chinês | MEDLINE | ID: mdl-17655138

RESUMO

OBJECTIVE: To provide anatomical evidences for the morphological and histological identification of 20 medicinal species in Hypericum. METHOD: Morphological and anatomical study on the organs of 20 medicinal species in Hypericum using tissue clearing, paraffin sectioning and thin sectioning. RESULT: According to their anatomical characteristics, the secretory structures can be divided into nodules, secretory cavities (canals) and tiny secretory tubes of 20 medicinal species in Hypericum. Hypericin was produced and stored in the nodules, while the volatile oil was produced and stored in the secretory cavities (canals) and tiny secretory tubes. The types differed markedly from each other in location, diameter and distributional density of leaf, and the anatomical structures differed from each other of stem, calyx, petal, anther and fruit among the 20 species in Hypericum. CONCLUSION: The secretory structures may be as anatomical evidences for the morphological and histological identification of 20 medicinal species in Hypericum.


Assuntos
Hypericum/anatomia & histologia , Plantas Medicinais/anatomia & histologia , Antracenos , Flores/anatomia & histologia , Flores/química , Frutas/anatomia & histologia , Frutas/química , Hypericum/química , Hypericum/classificação , Óleos Voláteis/análise , Perileno/análogos & derivados , Perileno/análise , Folhas de Planta/anatomia & histologia , Folhas de Planta/química , Caules de Planta/anatomia & histologia , Caules de Planta/química , Plantas Medicinais/química , Plantas Medicinais/classificação , Especificidade da Espécie
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