scholarly journals A Phenomenological Study on the Synergistic Role of Precious Metals in the Steam Reforming of Logistic Fuels on Trimetal-Supported Catalysts

2010 ◽  
Vol 2010 ◽  
pp. 1-12 ◽  
Author(s):  
Abdul-Majeed Azad ◽  
Desikan Sundararajan
Keyword(s):  
Steam Reforming ◽  
Precious Metal ◽  
Noble Metals ◽  
Phenomenological Study ◽  
Supported Catalysts ◽  
Precious Metals ◽  
Jet Fuels ◽  
Metal Loading

Fuel processors are required to convert sulfur-laden logistic fuels (jet fuels, diesel, and coal) into fuel cell quality hydrogen-rich reformate with little or no sulfur for extended periods. Sulfur poisons and deactivates the reforming catalyst, therefore, sulfur-tolerant catalysts ought to be developed. In this paper, the development, characterization, and evaluation of a series of nanoscale ceria-supported reforming catalysts containing three noble metals in low concentration (1 wt% ≤ total metal loading ≤ 1.33 wt%) for the steam-reforming of kerosene (a JP-8 surrogate) are reported. Their performance is quantified in terms of H2yield, tolerance towards sulfur in the fuel, and the on-stream stability and compared with that of monometal and bimetal analogs under identical conditions. Due to the inherent cooperative synergy, a trimetal catalyst was found far superior to its mono- and bimetallic analog containing same amount of the precious metal loading in terms of quality of the reformate (measured by H2level in steady-state) as well as the catalyst longevity on-stream prior to deactivation. At the same time a mechanistic correlation between the distinct role of a given precious metal and the extent of its loading in each of the formulations and quality of the corresponding desulfurized H2-rich reformate was discovered.

scholarly journals A Phenomenological Study on the Synergistic Role of Precious Metals and the Support in the Steam Reforming of Logistic Fuels on Monometal Supported Catalysts

2010 ◽  
Vol 2010 ◽  
pp. 1-15 ◽  
Author(s):  
Abdul-Majeed Azad ◽  
Desikan Sundararajan
Keyword(s):  
Steam Reforming ◽  
High Efficiency ◽  
Phenomenological Study ◽  
Supported Catalysts ◽  
Precious Metals ◽  
Sulfur Poisoning ◽  
Jet Fuels ◽  
Hydrogen Yield ◽  
High Hydrogen

Clean power source utilizing vast logistic fuel reserves (jet fuels, diesel, and coal) would be the main driver in the 21st century for high efficiency. Fuel processors are required to convert these fuels into hydrogen-rich reformate for extended periods in the presence of sulfur, and deliver hydrogen with little or no sulfur to the fuel cell stack. However, the jet and other logistic fuels are invariably sulfur-laden. Sulfur poisons and deactivates the reforming catalyst and therefore, to facilitate continuous uninterrupted operation of logistic fuel processors, robust sulfur-tolerant catalysts ought to be developed. New noble metal-supported ceria-based sulfur-tolerant nanocatalysts were developed and thoroughly characterized. In this paper, the performance of single metal-supported catalysts in the steam-reforming of kerosene, with 260 ppm sulfur is highlighted. It was found that ruthenium-based formulation provided an excellent balance between hydrogen production and stability towards sulfur, while palladium-based catalyst exhibited rapid and steady deactivation due to the highest propensity to sulfur poisoning. The rhodium supported system was found to be most attractive in terms of high hydrogen yield and long-term stability. A mechanistic correlation between the role of the nature of the precious metal and the support for generating clean desulfurized -rich reformate is discussed.

scholarly journals A Phenomenological Study on the Synergistic Role of Precious Metals in the Steam Reforming of Logistic Fuels on Bimetal-Supported Catalysts

2011 ◽  
Vol 2011 ◽  
pp. 1-12 ◽  
Author(s):  
Abdul-Majeed Azad ◽  
Desikan Sundararajan
Keyword(s):  
Steam Reforming ◽  
Noble Metals ◽  
Phenomenological Study ◽  
Hydrogen Generation ◽  
Bimetallic Catalyst ◽  
Supported Catalysts ◽  
Precious Metals ◽  
Weight Percent ◽  
Sulfur Tolerance

Fuel processors are required to convert sulfur-laden logistic fuels into hydrogen-rich reformate and deliver to the fuel cell stack with little or no sulfur. Since sulfur poisons and deactivates the reforming catalyst, robust sulfur-tolerant catalysts ought to be developed. In this paper, the development, characterization and evaluation of a series of reforming catalysts containing two noble metals (with total metal loading not exceeding 1 weight percent) supported on nanoscale ceria for the steam-reforming of kerosene is reported. Due to inherent synergy, a bimetallic catalyst is superior to its monometallic analog, for the same level of loading. The choice of noble metal combination in the bimetallic formulations plays a vital and meaningful role in their performance. Presence of ruthenium and/or rhodium in formulations containing palladium showed improved sulfur tolerance and significant enhancement in their catalytic activity and stability. Rhodium was responsible for higher hydrogen yields in the logistic fuel reformate. Duration of steady hydrogen production was higher in the case of RhPd (75 h) than for RuPd (68 h); hydrogen generation was stable over the longest period (88 h) with RuRh containing no Pd. A mechanistic correlation between the characteristic role of precious metals in the presence of each other is discussed.

scholarly journals Evaluasi Pengelolaan Dana Desa Pada BUMDes Serdang Tirta Kencana

2021 ◽  
Vol 3 (1) ◽  
pp. 63-72
Author(s):  
Silvia Puspitasari ◽  
Septian Bayu Kristanto
Keyword(s):  
Phenomenological Study ◽  
Financial Statements ◽  
Development Stage ◽  
Business Development ◽  
Primary Data ◽  
Fund Management ◽  
Study Approach

Village Fund Management in BUMDES can be carried out well if it applies the principles of accountability and transparency. However, not all BUMDESs in Indonesia are able to carry out these two principles properly and correctly because the quality of the training provided by BUMDES is still not good. Therefore, the purpose of this research is to determine how the role of BUMDES in improving the economy of the surrounding community, the role of BUMDES administrators in optimizing village fund management and the effect of accountability, transparency and quality of training on village fund management. The type of this research is qualitative with a phenomenological study approach. The types of data in this research are secondary and primary data. Data can be obtained from the BUMDES Serdang Tirta Kencana Financial Statements, other supporting documents and interviews. The results of this research indicate that the principle of accountability in managing village funds in BUMDES Serdang Tirta Kencana can’t be implemented optimally, the principle of transparency in managing village funds in BUMDES Serdang Tirta Kencana can be implemented well, business development of BUMDES Serdang Tirta Kencana currently in the development stage and the performance of the management at BUMDES Serdang Tirta Kencana is already good. However, there are still weaknesses because there are still managers who are not on time.

scholarly journals Development of explosive breaking principles for the ores prone to overgrinding

2020 ◽  
Vol 192 ◽  
pp. 01016
Author(s):  
Artem Rozhkov ◽  
Igor Sokolov ◽  
Yuri Antipin ◽  
Kirill Baranovsky
Keyword(s):  
Precious Metal ◽  
Statistical Evaluation ◽  
Underground Mining ◽  
Raw Materials ◽  
Precious Metals ◽  
Mining Enterprise ◽  
Ore Minerals ◽  
Technological Methods ◽  
Mineral Reserves

In underground mining of valuable non-metallic raw materials, non-ferrous and precious metal ores, the problem of overgrinding of raw materials as a result of blasting operations is quite acute. For ores of nonferrous and precious metals, represented by strong rocks, the effect of increased concentration of ore minerals in small classes of ore is characteristic. Due to the process of segregation of the mass in ore drawing, small fractions accumulate in significant quantities on the lying side of the mine goaf and on the roughness of its surface. Such ore is often simply lost. It is rational to create conditions for reducing the yield of small fractions already at the stage of separating the ore from the array. Therefore, the development of technological methods for managing the quality of mining enterprise products and methods for improving the completeness of extracting mineral reserves is an urgent scientific and technical task. To solve this problem, a number of model and full-scale experiments were conducted to identify the dependence of the nature of destruction on the method and parameters of blasting, followed by statistical evaluation of the results. The principles of determining the parameters of the technology for breaking valuable ores that are prone to overgrinding are established.

scholarly journals Caregivers of Patients with Hematological Malignancies within Home Care: A Phenomenological Study

2020 ◽  
Vol 17 (11) ◽  
pp. 4036
Author(s):  
Isabella Capodanno ◽  
Mirta Rocchi ◽  
Rossella Prandi ◽  
Cristina Pedroni ◽  
Enrica Tamagnini ◽  
...  
Keyword(s):  
Home Care ◽  
End Of Life ◽  
End Of Life Care ◽  
Hematological Malignancies ◽  
Phenomenological Study ◽  
Primary Caregivers ◽  
Life Care ◽  
Ethical Aspects

The role of caregivers in homecare settings is relevant to the patient’s wellbeing and quality of life. This phenomenon is well described in the literature for the oncological setting but not specifically for that of hematological malignancies. The aim of this study was to explore the experience of primary caregivers of patients with hematological malignancies within home care. We conducted a phenomenological study based on interviews with 17 primary caregivers of hematological patients. Analysis of the contents led to the identification of five main themes. Perhaps, the innovative aspects of this study can be summarized in three points: This service was demonstrated to fulfil the ethical aspects of providing the patient with a dignified accompaniment to the end of life. Secondly, the efficiency of the service and the benefit are directly dependent on the caregivers’ wellbeing, so knowledge of the dynamics and emotions involved can lead to the development and implementation of programs for hematological malignancies. Lastly, a collaborative caregivers–professionals relationship can improve a sense of accomplishment for all parties involved, lessening the family’s frustration related to not having done their best. Home care brings significant benefits for both the patient and the caregivers and fulfils the ethical obligation of providing the patient dignified end-of-life care.

Microstructure and reactivity of small metal particles: The role of Ce additives

1992 ◽  
Vol 50 (1) ◽  
pp. 318-319
Author(s):  
L.D. Schmidt ◽  
K. R. Krause ◽  
J. M. Schwartz ◽  
X. Chu
Keyword(s):  
Atmospheric Pressure ◽  
Noble Metals ◽  
Mixed Oxides ◽  
Catalytic Properties ◽  
Chemical Shifts ◽  
Catalytic Converter ◽  
Structural Evolution ◽  
Single Particles ◽  
Small Metal Particles

The evolution of microstructures of 10- to 100-Å diameter particles of Rh and Pt on SiO2 and Al2O3 following treatment in reducing, oxidizing, and reacting conditions have been characterized by TEM. We are able to transfer particles repeatedly between microscope and a reactor furnace so that the structural evolution of single particles can be examined following treatments in gases at atmospheric pressure. We are especially interested in the role of Ce additives on noble metals such as Pt and Rh. These systems are crucial in the automotive catalytic converter, and rare earths can significantly modify catalytic properties in many reactions. In particular, we are concerned with the oxidation state of Ce and its role in formation of mixed oxides with metals or with the support. For this we employ EELS in TEM, a technique uniquely suited to detect chemical shifts with ∼30Å resolution.

Cognitive Health Counseling 40+

2013 ◽  
Vol 21 (1) ◽  
pp. 24-33 ◽  
Author(s):  
Anne Eschen ◽  
Franzisca Zehnder ◽  
Mike Martin
Keyword(s):  
Outcome Variable ◽  
Pilot Phase ◽  
Subjective Memory ◽  
Cognitive Health ◽  
Health Counseling ◽  
Agents Of Change ◽  
Main Outcome Variable ◽  
Further Development

This article introduces Cognitive Health Counseling 40+ (CH.CO40+), an individualized intervention that is conceptually based on the orchestration model of quality-of-life management ( Martin & Kliegel, 2010 ) and aims at improving satisfaction with cognitive health in adults aged 40 years and older. We describe the theoretically deduced characteristics of CH.CO40+, its target group, its multifactorial nature, its individualization, the application of subjective and objective measures, the role of participants as agents of change, and the rationale for choosing participants’ satisfaction with their cognitive health as main outcome variable. A pilot phase with 15 middle-aged and six older adults suggests that CH.CO40+ attracts, and may be particularly suitable for, subjective memory complainers. Implications of the pilot data for the further development of the intervention are discussed.

Sign in / Sign up

Export Citation Format

Share Document