scholarly journals Understanding of the Key Factors Determining the Activity and Selectivity of CuZn Catalysts in Hydrogenolysis of Alkyl Esters to Alcohols

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1417
Author(s):  
Oleg Kikhtyanin ◽  
Jaroslav Aubrecht ◽  
Violetta Pospelova ◽  
David Kubička
Keyword(s):  
Catalytic Performance ◽  
Key Factors ◽  
Alkyl Esters ◽  
Consecutive Reaction ◽  
Structure Activity ◽  
Methyl Hexanoate ◽  
Co Precipitation ◽  
Reaction Cycles ◽  
The Impact ◽  
Effect Of The Composition

CuZn catalysts are perspective catalysts for esters hydrogenolysis, but more knowledge is needed to optimize their catalytic performance. In this work, we consider the impact of CuZn catalysts composition on their structure, activity, selectivity, and stability in esters hydrogenolysis. Four catalysts with various Cu/Zn ratio were synthesized by a co-precipitation and characterized in as-prepared, calcined, reduced, and spent state by XRF, XRD, N2 physisorption, CO2-TPD, NH3-TPD, and N2O chemisorption. XRD data revealed the effect of the composition on the size of Cu and ZnO particles. The catalytic performance was investigated using an autoclave. All catalysts exhibited high methyl hexanoate conversion about 48–60% after 3 h but their activity and selectivity were found to be dependent on Cu/Zn ratio. The conversion of methyl hexanoate and hexyl hexanoate was compared to explain the observed product selectivity. Moreover, the catalysts stability was investigated in three consecutive reaction cycles and correlated with changes in the size of constituent particles. Moreover, when different esters were tested, a slight decrease in conversion and increase in alcohol selectivity with a growth in molecule size was observed. Obtained results allow making a conclusion about the optimal composition that provides the good performance of CuZn catalysts in ester hydrogenolysis.

Secular stagnation in the modern world

2018 ◽  
pp. 125-141 ◽  
Author(s):  
S. M. Drobyshevsky ◽  
P. V. Trunin ◽  
A. V. Bozhechkova
Keyword(s):  
Public Debt ◽  
Capital Accumulation ◽  
Technological Development ◽  
Japanese Economy ◽  
Modern World ◽  
Key Factors ◽  
Destruction Process ◽  
Secular Stagnation ◽  
The Impact

The paper studies the factors of secular stagnation. Key factors of long-term slowdown in economic growth include the slowdown of technological development, aging population, human capital accumulation limits, high public debt, creative destruction process violation etc. The authors analyze key theoretical aspects of long-term stagnation and study the impact of these factors on Japanies economy. The authors conclude that most of the factors have significant influence on the Japanese economy for recent decades, but they cannot explain all dynamics. For Russia, on the contrary, we do not see any grounds for considering the decline in the economy since 2013 as an episode of secular stagnation.

Implication of Medical Treatment for Surgical Strategies in IBD

2019 ◽  
Vol 20 (13) ◽  
pp. 1363-1368
Author(s):  
Krisztina B. Gecse ◽  
Christianne J. Buskens
Keyword(s):  
Nutritional Status ◽  
Medical Treatment ◽  
Significant Proportion ◽  
Timing Of Surgery ◽  
Multidisciplinary Management ◽  
Key Factors ◽  
Surgical Strategies ◽  
Immunosuppressive Medications ◽  
Medical Paradigm ◽  
The Impact

Despite changing medical paradigm, still a significant proportion of patients with IBD require surgery. The patient's general condition, including nutritional status and the use of immunosuppressive medications is of great importance with regard to surgical complications, as well as the choice of optimal surgical strategy. The indication and the timing of surgery are key factors for the multidisciplinary management of IBD patients. The purpose of this review is to provide an overview on the impact of medical treatment on surgical strategies in IBD.

Examining Organizational, Cultural, and Individual-Level Factors Related to Workplace Safety and Health Awareness and Risks: A Systematic Review and Metric Analysis (Preprint)

2018 ◽  
Author(s):  
Edmund W. J. Lee ◽  
Han Zheng ◽  
Htet Htet Aung ◽  
Megha Rani Aroor ◽  
Chen Li ◽  
...  
Keyword(s):  
Systematic Review ◽  
Citation Count ◽  
Workplace Safety ◽  
Key Factors ◽  
Health Awareness ◽  
Individual Level ◽  
Metric Analysis ◽  
Safety And Health ◽  
The Impact ◽  
The Relationship

BACKGROUND Promoting safety and health awareness and mitigating risks are of paramount importance to companies in high-risk industries. Yet, there are very few studies that have synthesized findings from existing online workplace safety and health literature to identify what are the key factors that are related to (a) safety awareness, (b) safety risks, (c) health awareness, and (d) health risks. OBJECTIVE As one of the first systematic reviews in the area of workplace health and safety, this study aims to identify the factors related to safety and health awareness as well as risks, and systematically map these factors within three levels: organizational, cultural, and individual level. Also, this review aims to assess the impact of these workplace safety and health publications in both academic (e.g., academic databases, Mendeley, and PlumX) and non-academic settings (e.g., social media platform). METHODS The systematic review was conducted in line with procedures recommended by Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). First, Proquest, ScienceDirect and Scopus were identified as suitable databases for the systematic review. Second, after inputting search queries related to safety and health awareness and risks, the articles were evaluated based on a set of inclusion and exclusion criteria. Third, the factors identified in the included articles were coded systematically. Fourth, the research team assessed the impact of the articles through a combination of traditional and new metric analysis methods: citation count, Altmetric Attention Score, Mendeley readers count, usage count, and capture count. RESULTS Out of a total of 4,831 articles retrieved from the three databases, 51 articles were included in the final sample and were systematically coded. The results revealed six categories of organizational (management commitment, management support, organizational safety communication, safety management systems, physical work environment, and organizational environment), two cultural (interpersonal support and organizational culture), and four individual (perception, motivation, attitude and behavior) level factors that relate to safety and health awareness and risk. In terms of impact, the relationship between citation count and the various metrics measuring academic activity (e.g., Mendeley readers, usage count, and capture count) were mostly significant while the relationship between citation count and Altmetric Attention Score was non-significant. CONCLUSIONS This study provides a macro view of the current state of workplace safety and health research and gives scholars an indication on some of the key factors of safety and health awareness and risks. Researchers should also be cognizant that while their work may receive attention from the scholarly community, it is important to tailor their communication messages for the respective industries they are studying to maximize the receptivity and impact of their findings. CLINICALTRIAL N.A.

Poland

2017 ◽  
Author(s):  
Detlef Pollack ◽  
Gergely Rosta
Keyword(s):  
Catholic Church ◽  
Agricultural Production ◽  
The State ◽  
Religious Culture ◽  
Key Factors ◽  
Pope John Paul Ii ◽  
National Values ◽  
The Impact ◽  
State Socialist ◽  
The Church

The chapter on Poland focuses on two questions. Why, in contrast to all other state-socialist countries, did the church’s capacity for integration actually increase rather than decrease despite persecution and discrimination during the communist period? And why has this capacity also remained more or less constant (albeit to a lesser extent) in the period since the end of communist rule? The authors have identified four key factors in the remarkable resistance of the Polish Catholic Church during the period of communist persecution: the fusion of religious and national values, the specific conflict dynamics of the church’s struggle with the state, the structural conservatism of agricultural production in Poland, and the actions of Pope John Paul II. Explanations for the surprising stability of religiosity in Poland after 1990 point to the behaviour of the Church itself, to the internal pluralization of Catholicism, and to the impact of a homogeneous religious culture.

scholarly journals Graphene-based 3D XNOR-VRRAM with ternary precision for neuromorphic computing

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Batyrbek Alimkhanuly ◽  
Joon Sohn ◽  
Ik-Joon Chang ◽  
Seunghyun Lee
Keyword(s):  
Neural Network ◽  
Energy Consumption ◽  
Recognition Accuracy ◽  
Material Selection ◽  
Weighted Sum ◽  
Device Design ◽  
Key Factors ◽  
Neuromorphic Computing ◽  
Device Scaling ◽  
The Impact

AbstractRecent studies on neural network quantization have demonstrated a beneficial compromise between accuracy, computation rate, and architecture size. Implementing a 3D Vertical RRAM (VRRAM) array accompanied by device scaling may further improve such networks’ density and energy consumption. Individual device design, optimized interconnects, and careful material selection are key factors determining the overall computation performance. In this work, the impact of replacing conventional devices with microfabricated, graphene-based VRRAM is investigated for circuit and algorithmic levels. By exploiting a sub-nm thin 2D material, the VRRAM array demonstrates an improved read/write margins and read inaccuracy level for the weighted-sum procedure. Moreover, energy consumption is significantly reduced in array programming operations. Finally, an XNOR logic-inspired architecture designed to integrate 1-bit ternary precision synaptic weights into graphene-based VRRAM is introduced. Simulations on VRRAM with metal and graphene word-planes demonstrate 83.5 and 94.1% recognition accuracy, respectively, denoting the importance of material innovation in neuromorphic computing.

scholarly journals Effective Demand Forecasting in Health Supply Chains: Emerging Trend, Enablers, and Blockers

Logistics ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 12
Author(s):  
Lakshmy Subramanian
Keyword(s):  
Supply Chains ◽  
Demand Forecasting ◽  
Weak Links ◽  
Key Factors ◽  
Scarce Resources ◽  
Weakest Link ◽  
Emerging Trends ◽  
A Chain ◽  
Health Commodities ◽  
The Impact

Health supply chains aim to improve access to healthcare, and this can be attained only when health commodities appropriate to the health needs of the global population are developed, manufactured, and made available when and where needed. The weak links in the health supply chains are hindering the access of essential healthcare resulting in inefficient use of scarce resources and loss of lives. A chain is only as strong as its weakest link, and demand forecasting is one of the weakest links of health supply chains. Also, many of the existing bottlenecks in supply chains and health systems impede the accurate forecasting of demand, and without the ability to forecast demand with certainty, the stakeholders cannot plan and make commitments for the future. Forecasts are an important feeder for budgeting and logistics planning. Under this backdrop, the study examines how improved forecasting can lead to better short-term and long-term access to health commodities and outlines market-related risks. It explores further how incentives are misaligned creating an uneven distribution of risks, leading to the inability to match demand and supply. For this purpose, a systematic literature review was performed, analyzing 71 articles from a descriptive and content approach. Findings indicate the emerging trends in global health and the consequences of inaccurate demand forecasting for health supply chains. The content analysis identifies key factors that can pose a varying degree of risks for the health supply chain stakeholders. The study highlights how the key factors emerge as enablers and blockers, depending on the impact on the overall health supply chains. The study also provides recommendations for actions for reducing these risks. Consequently, limitations of this work are presented, and opportunities are identified for future lines of research. Finally, the conclusion confirms that by adopting a combination of approaches, stakeholders can ensure better information sharing, identify avenues of diversifying risks, and understand the implications.

scholarly journals The Catalytic Oxidation of Formaldehyde by FeOx-MnO2-CeO2 Catalyst: Effect of Iron Modification

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 555
Author(s):  
Yaxin Dong ◽  
Chenguang Su ◽  
Kai Liu ◽  
Haomeng Wang ◽  
Zheng Zheng ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Oxygen Vacancies ◽  
Catalytic Performance ◽  
Active Oxygen ◽  
Molar Ratio ◽  
N2 Adsorption ◽  
Structure Activity ◽  
Iron Modification ◽  
Surface Active ◽  
Catalyst Effect

A series of FeOx-MnO2-CeO2 catalysts were synthesized by the surfactant-templated coprecipitation method and applied for HCHO removal. The influence of Fe/Mn/Ce molar ratio on the catalytic performance was investigated, and the FeOx-MnO2-CeO2 catalyst exhibited excellent catalytic activity, with complete HCHO conversion at low temperatures (40 °C) when the molar ratio of Fe/Mn/Ce was 2/5/5. The catalysts were characterized by N2 adsorption and desorption, XRD, H2-TPR, O2-TPD and XPS techniques to illustrate their structure–activity relationships. The result revealed that the introduction of FeOx into MnO2-CeO2 formed a strong interaction between FeOx-MnO2-CeO2, which facilitated the improved dispersion of MnO2-CeO2, subsequently increasing the surface area and aiding pore development. This promotion effect of Fe enhanced the reducibility and produced abundant surface-active oxygen. In addition, a great number of Oα is beneficial to the intermediate decomposition, whereas the existence of Ce3+ favors the formation of oxygen vacancies on the surface of the catalyst, all of which contributed to HCHO oxidation at low temperatures.

scholarly journals The Impact of Policy Measures on Human Mobility, COVID-19 Cases, and Mortality in the US: A Spatiotemporal Perspective

2021 ◽  
Vol 18 (3) ◽  
pp. 996
Author(s):  
Yun Li ◽  
Moming Li ◽  
Megan Rice ◽  
Haoyuan Zhang ◽  
Dexuan Sha ◽  
...  
Keyword(s):  
Growth Rate ◽  
Human Mobility ◽  
Public Information ◽  
Key Factors ◽  
Information Campaigns ◽  
Rapid Spread ◽  
The Us ◽  
Policy Measures ◽  
The Impact ◽  
At Home

Social distancing policies have been regarded as effective in containing the rapid spread of COVID-19. However, there is a limited understanding of policy effectiveness from a spatiotemporal perspective. This study integrates geographical, demographical, and other key factors into a regression-based event study framework, to assess the effectiveness of seven major policies on human mobility and COVID-19 case growth rates, with a spatiotemporal emphasis. Our results demonstrate that stay-at-home orders, workplace closures, and public information campaigns were effective in decreasing the confirmed case growth rate. For stay-at-home orders and workplace closures, these changes were associated with significant decreases (p < 0.05) in mobility. Public information campaigns did not see these same mobility trends, but the growth rate still decreased significantly in all analysis periods (p < 0.01). Stay-at-home orders and international/national travel controls had limited mitigation effects on the death case growth rate (p < 0.1). The relationships between policies, mobility, and epidemiological metrics allowed us to evaluate the effectiveness of each policy and gave us insight into the spatiotemporal patterns and mechanisms by which these measures work. Our analysis will provide policymakers with better knowledge regarding the effectiveness of measures in space–time disaggregation.

scholarly journals Measuring capability wellbeing in adults at different stages of life for use in economic evaluation of health and care interventions: a qualitative investigation in people requiring kidney care

2021 ◽  
Author(s):  
Paul Mark Mitchell ◽  
Samantha Husbands ◽  
Sabina Sanghera ◽  
Fergus John Caskey ◽  
Jemima Scott ◽  
...  
Keyword(s):  
Life Stage ◽  
Structured Interview ◽  
Health Conditions ◽  
Economic Evaluations ◽  
Qualitative Investigation ◽  
Key Factors ◽  
Younger Adults ◽  
Patient Groups ◽  
The Life Course ◽  
The Impact

Abstract Purpose Capability wellbeing measures, such as the ICECAP measures, have been proposed for use in economic evaluations to capture broader outcomes of health and care interventions. The ICECAP measures have been developed to reflect capabilities at different stages of life. Some patient groups include patients of different ages and at different stages of life, so it is not always apparent which ICECAP measure is most relevant. This study explores the impact of age and life stage on completion, where both ICECAP-A and ICECAP-O were completed by the same patient. Methods A think-aloud study, and an associated semi-structured interview were conducted with people receiving kidney care as a renal outpatient, kidney transplant outpatient, or through receiving facility-based haemodialysis. Qualitative analysis focused on (1) differences in responses across measures by individuals, where attributes had conceptual overlap, (2) key factors in self-reported capability levels, and (3) measure preference. Results Thirty participants were included in the study, with a mix of older and younger adults. Attributes with similar wording across measures produced similar responses compared to attributes where wording differed. Age and health were key factors for self-reported capability levels. ICECAP-A was slightly preferred overall, including by older adults. Conclusion This study suggests use of ICECAP-A in patients with certain chronic health conditions that include a mix of adults across the life course. This study highlights the importance of considering the stage of life when using capability measures and in economic evaluations of health and care interventions more generally.

Effect of Fe and Co promoters on CO methanation activity of nickel catalyst prepared by impregnation – co-precipitation method

2020 ◽  
Vol 18 (5-6) ◽  
Author(s):  
Buyan-Ulzii Battulga ◽  
Tungalagtamir Bold ◽  
Enkhsaruul Byambajav
Keyword(s):  
Synergetic Effect ◽  
Space Velocity ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Alumina Support ◽  
Co Methanation ◽  
Temperature Range ◽  
Co Precipitation ◽  
Catalyst Distribution

AbstractNi based catalysts supported on γ-Al2O3 that was unpromoted (Ni/γAl2O3) or promoted (Ni–Fe/γAl2O3, Ni–Co/γAl2O3, and Ni–Fe–Co/γAl2O3) were prepared using by the impregnation – co-precipitation method. Their catalytic performances for CO methanation were studied at 3 atm with a weight hourly space velocity (WHSV) of 3000 ml/g/h of syngas with a molar ratio of H2/CO = 3 and in the temperature range between 130 and 350 °C. All promoters could improve nickel distribution, and decreased its particle sizes. It was found that the Ni–Co/γAl2O3 catalyst showed the highest catalytic performance for CO methanation in a low temperature range (<250 °C). The temperatures for the 20% CO conversion over Ni–Co/γAl2O3, Ni–Fe/γAl2O3, Ni–Fe–Co/γAl2O3 and Ni/γAl2O3 catalysts were 205, 253, 263 and 270 °C, respectively. The improved catalyst distribution by the addition of cobalt promoter caused the formation of β type nickel species which had an appropriate interacting strength with alumina support in the Ni–Co/γAl2O3. Though an addition of iron promoter improved catalyst distribution, the methane selectivity was lowered due to acceleration of both CO methanation and WGS reaction with the Ni–Fe/γAl2O3. Moreover, it was found that there was no synergetic effect from the binary Fe–Co promotors in the Ni–Fe–Co/γAl2O3 on catalytic activity for CO methanation.

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