368 research outputs found

    Peranan Organisasi Karang Taruna dalam Pemberdayaan Masyarakat Desa (suatu Studi di Desa Tewasen, Desa Pondos, Desa Elusan, Desa Wakan Kecamatan Amurang Barat Kabupaten Minahasa Selatan)

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    Observe to the problem that faced by young generation, it is necessary to attempt that will helpthose young generation to solve problems which that attempt need a place to develop and direct them. Theimplementation of development is a government duty from national to local government with appropriateexpertise. Then the implementation will translate to society life especially in counselling such as build anorganization that become a place to develop young generation in village. As an example is Karang Tarunathat can be a place to accommodating the aspirations and involved young generation to manage. Beside,Karang Taruna also play role as place to grow sense of nationality, develop self potency and social welfare.Research Method : This research using descriptive qualitative approaching method by deep interview to 7responden, observe and files investigation using additional instruments such as interview guidance list,recorder and stationery. Research results : According the role of Karang Taruna from 4 villages, they haven'timplemented the main role and duty as a organization yet. There were only two villages that have a goodimplementation , they are Tewasen and Pondos Village while the other two haven't optimal implementationyet. Karang Taruna of Pondos Village has a good program's plan but in their role as a government partner insociety welfare hasn't optimal yet while good partnership shown is social life but need more guidance. Elusanand Wakan Village had not an optimal program's plan, society empowerment and social welfare. Conclution :There are only two Karang Taruna with a good role implementation of society empowerment from fourKarang Taruna as an object of this research. They are Karang Taruna of Tewasen and Pondos Village whileKarang Taruna of Elusan and Wakan Village haven't good implementation yet

    In situ surface coverage analysis of RuO<sub>2</sub>-catalysed HCl oxidation reveals the entropic origin of compensation in heterogeneous catalysis

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    In heterogeneous catalysis, rates with Arrhenius-like temperature dependence are ubiquitous. Compensation phenomena, which arise from the linear correlation between the apparent activation energy and the logarithm of the apparent pre-exponential factor, are also common. Here, we study the origin of compensation and find a similar dependence on the rate-limiting surface coverage term for each Arrhenius parameter. This result is derived from an experimental determination of the surface coverage of oxygen and chlorine species using temporal analysis of products and prompt gamma activation analysis during HCl oxidation to Cl2 on a RuO2 catalyst. It is also substantiated by theory. We find that compensation phenomena appear when the effect on the apparent activation energy caused by changes in surface coverage is balanced out by the entropic configuration contributions of the surface. This result sets a new paradigm in understanding the interplay of compensation effects with the kinetics of heterogeneously catalysed processes

    Phase Coexistence and Structural Dynamics of Redox Metal Catalysts Revealed by Operando TEM

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    Metal catalysts play an important role in industrial redox reactions. Although extensively studied, the state of these catalysts under operating conditions is largely unknown, and assignments of active sites remain speculative. Herein, an operando transmission electron microscopy study is presented, which interrelates the structural dynamics of redox metal catalysts to their activity. Using hydrogen oxidation on copper as an elementary redox reaction, it is revealed how the interaction between metal and the surrounding gas phase induces complex structural transformations and drives the system from a thermodynamic equilibrium toward a state controlled by the chemical dynamics. Direct imaging combined with the simultaneous detection of catalytic activity provides unparalleled structure–activity insights that identify distinct mechanisms for water formation and reveal the means by which the system self-adjusts to changes of the gas-phase chemical potential. Density functional theory calculations show that surface phase transitions are driven by chemical dynamics even when the system is far from a thermodynamic phase boundary. In a bottom-up approach, the dynamic behavior observed here for an elementary reaction is finally extended to more relevant redox reactions and other metal catalysts, which underlines the importance of chemical dynamics for the formation and constant re-generation of transient active sites during catalysis

    Do observations on surface coverage-reactivity correlations always describe the true catalytic process? A case study on ceria

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    In situ (operando) investigations aim at establishing structure-function and/or coverage-reactivity correlations. Herein, we investigated the gas-phase HCl oxidation (4HCl + O2 → 2Cl2 + 2H2O) over ceria. Despite its remarkable performance, under low oxygen over-stoichiometry, this oxide is prone to a certain extent to subsurface/bulk chlorination, which leads to deactivation. In situ Prompt Gamma Activation Analysis (PGAA) studies evidenced that the chlorination rate is independent of the pre-chlorination degree but increases at lower oxygen over-stoichiometry, while dechlorination is effective in oxygen-rich feeds, and its rate is higher for a more extensively pre-chlorinated ceria. Even bulk CeCl3 could be transformed into CeO2 under oxygen excess. Electron Paramagnetic Resonance experiments strongly suggested that oxygen activation is inhibited by a high surface chlorination degree. The coverages of most abundant surface intermediates, OH and Cl, were monitored by in situ infrared spectroscopy and PGAA under various conditions. Higher temperature and p(O2) led to enhanced OH coverage, reduced Cl coverage, and increased reactivity. Variation of p(HCl) gave rise to opposite correlations, while raising p(Cl2) did not induce any measurable increase in the Cl coverage, despite the strong inhibition of the reaction rate. The results indicate that only a small fraction of surface sites is actively involved in the reaction, and most of the surface species probed in the in situ observation are spectators. Therefore, when performing in situ steady-state experiments, a large set of variables should be considered to obtain accurate conclusions

    Propaedeutic study for the delivery of nucleic acid-based molecules from PLGA microparticles and stearic acid nanoparticles

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    We studied the mechanism governing the delivery of nucleic acid-based drugs (NABD) from microparticles and nanoparticles in zero shear conditions, a situation occurring in applications such as in situ delivery to organ parenchyma. The delivery of a NABD molecule from poly(DL-lactide-co-glycolide) (PLGA) microparticles and stearic acid (SA) nanoparticles was studied using an experimental apparatus comprising a donor chamber separated from the receiver chamber by a synthetic membrane. A possible toxic effect on cell biology, as evaluated by studying cell proliferation, was also conducted for just PLGA microparticles. A mathematical model based on the hypothesis that NABD release from particles is due to particle erosion was used to interpret experimental release data. Despite zero shear conditions imposed in the donor chamber, particle erosion was the leading mechanism for NABD release from both PLGA microparticles and SA nanoparticles. PLGA microparticle erosion speed is one order of magnitude higher than that of competing to SA nanoparticles. Finally, no deleterious effects of PLGA microparticles on cell proliferation were detected. Thus, the data here reported can help optimize the delivery systems aimed at release of NABD from micro- and nanoparticles

    International overview of somatic dysfunction assessment and treatment in osteopathic research: A scoping review

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    Background: Osteopathic manipulative treatment (OMT) is a patient-centred, whole-body intervention aimed at enhance the person’s self-regulation. OMT interventions are focused on somatic dysfunctions (SD) that can be defined as an altered regulative function associated with inflammatory signs palpable in the body framework in different body regions. The conceptual model that sustains SD, as well as its usefulness for the osteopathic profession, is still being discussed by the osteopathic community. Understanding the role and the application of SD is the aim of this scoping review. Methods: A literature search was carried out through the main biomedical databases: Pubmed (Medline), Cochrane, Central (Cochrane), Embase, PEDro and Scopus. Grey literature was considered via Google Scholar and the Osteopathic Research Web. The review was prepared by referring to the “Preferred Reporting Items for Systematic reviews and Meta-Analysis extension for Scoping Reviews” (PRISMA-ScR). Results: A total of 37,279 records were identified through database searching and other sources. After the duplicates were removed, 27,023 titles and abstracts were screened. A total of 1495 full-text articles were assessed for eligibility. The qualitative synthesis included 280 studies. Conclusions: Treating SD is an important part of osteopathic practice that varies from country to country. SD should be considered as a clinical value that assists in the clinical assessment and guides the decision-making process of osteopathic practitioners. Further studies should be designed to better understand why and how to choose the different assessment and intervention modalities to approach SD and to evaluate new osteopathic models

    Using GIS in Sustainable Urban Design in Developing Countries (Gaza Strip, Palestine as a Case study)

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    Gaza Strip -Palestine is one of most needy regions to apply sustainability concepts and sustainable planning, owing to its critical narrow area of nearly 365 KM2. In addition, overpopulation and the increasing depletion of limited natural resources are of major concerns. Moreover, the conventional urban planning has failed to solve the ecological and economic problems, and even sometimes aggravates them. This research aims to analyze one of the urban projects in Gaza Strip (Sheikh Zayed City), study their appropriateness and application of sustainability concepts by using the technology of Geographical Information Systems (GIS). In addition to recognize the most important criteria, fundamentals and standard indicators required for accomplishing the sustainable urban planning status of the Gaza Strip. Keywords: GIS, Urban Design Strategies, Sustainability, Gaza Stri

    Performance, structure, and mechanism of CeO<sub>2</sub> in HCl oxidation to Cl<sub>2</sub>

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    Experimental and theoretical studies reveal performance descriptors and provide molecular-level understanding of HCl oxidation over CeO2. Steady-state kinetics and characterization indicate that CeO2 attains a significant activity level, which is associated with the presence of oxygen vacancies. Calcination of CeO2 at 1173 K prior to reaction maximizes both the number of vacancies and the structural stability of the catalyst. X-ray diffraction and electron microscopy of samples exposed to reaction feeds with different O2/HCl ratios provide evidence that CeO2 does not suffer from bulk chlorination in O2-rich feeds (O2/HCl ≥ 0.75), while it does form chlorinated phases in stoichiometric or sub-stoichiometric feeds (O2/HCl ≤ 0.25). Quantitative analysis of the chlorine uptake by thermogravimetry and X-ray photoelectron spectroscopy indicates that chlorination under O2-rich conditions is limited to few surface and sub-surface layers of CeO2 particles, in line with the high energy computed for the transfer of Cl from surface to sub-surface positions. Exposure of chlorinated samples to a Deacon mixture with excess oxygen rapidly restores the original activity levels, highlighting the dynamic response of CeO2 outermost layers to feeds of different composition. Density functional theory simulations reveal that Cl activation from vacancy positions to surface Ce atoms is the most energy-demanding step, although chorine-oxygen competition for the available active sites may render re-oxidation as the rate-determining step. The substantial and remarkably stable Cl2 production and the lower of CeO2 make it an attractive alternative to RuO2 for catalytic chlorine recycling in industry

    Pengembangan Produk Tempat Sampah Penghancur Plastik Berbasis Green Technology

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    – Inovasi merupakan aspek kunci yang mendorong suatu Perusahaan semakin berkembang dan tetap bertahan dalam ketatnya persaingan di pasar. Seiringan dengan perkembangan teknologi yang revolusioner, menimbulkan adanya kebutuhan akan produk-produk dengan kemampuan yang mutakhir, oleh karena itu dibutuhan pola pikir yang kreatif dan berorientasi pada kreativitas bagi para Perusahaan untuk tetap mempertahankan kedudukannya di persaingan pasar. Dalam upaya menghasilkan produk yang inovatif dan berkualitas tinggi, diperlukan perencanaan dan pengembangan produk yang komprehensif, selain itu juga diharapkan memiliki manfaat yang berkelanjutan dan bermanfaat bagi kelestarian lingkungan. Salah satu orientasi yang ditujukan pada Perusahaan saat ini ialah mengembangkan Green Technology yang merujuk pada pembangunan dan aplikasi produk, peralatan serta sistem untuk memelihara alam sekitar dan meminimumkan dampak kerusakan lingkungan yang diakibatkan oleh manusia. Pada penelitian ini, dilakukan perencanaan dan pengembangan produk tempat sampah penghancur plastik ramah lingkungan bertenaga mekanik, dengan sensor elektrik yang mampu mendeteksi ketinggian sampah agar tidak menumpuk. Alur penelitian dilakukan mulai dari pencarian dan pengumpulan ide produk, penyaringan ide produk yang feasible dan berpotensi menguntungkan, pembuatan prototipe produk, hingga analisis ekonomi dari produk yang akan dikembangkan. Tempat sampah penghancur sampah yang ramah lingkungan ini diberi nama Trade (Trash Destroyer)
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