Researches on Fractal Features of Graphite Porous Materials

2012 ◽  
Vol 507 ◽  
pp. 25-29 ◽  
Author(s):  
Qi Liu ◽  
Ya Fei Hu ◽  
Qi Li Wang
Keyword(s):  
Fractal Dimension ◽  
Pore Formation ◽  
Inflection Point ◽  
Pore Diameter ◽  
Mercury Porosimetry ◽  
Microscopic Structure ◽  
Fractal Characteristics ◽  
The One ◽  
Main Factor

The mercury porosimetry experiment has tested three different kinds of porosity graphite and the microscopic structure of impregnation antimony materials, and has calculated the corresponding fractal dimension by using the Menger model. The results show that: the main pore diameter of the graphite materials is in the interval of , most of which can be filled by impregnation antimony, and graphite and impregnation antimony materials both have the fractal characteristics. Graphite materials also have the dual fractal characteristics. Its fractal inflection point aperture is about 1μm, and the fractal dimension (3.05 ~ 3.25) of the small pores (φ≤1μm) is less than the one (3.71 ~ 3.95) of the large pores (φ>1μm). The reason why existing the dual fractal characteristics is that the size of the pore formation mechanism is different. Impregnation occurs mainly in the range of large pores, characteristics of which is an important factor to influence the quality of impregnation materials. The material formula is the main factor to influence the large pores and an important guarantee to improve the quality of impregnation products.

The Pore Fractal Characteristics of Concrete Materials under Salt Freezing Conditions in Cold Area

2011 ◽  
Vol 233-235 ◽  
pp. 2522-2527
Author(s):  
Ming Tang ◽  
Yong Tian ◽  
Xiao Bo Mu ◽  
Ming Jiang
Keyword(s):  
Fractal Dimension ◽  
Pore Diameter ◽  
Total Porosity ◽  
Freezing Injury ◽  
Air Content ◽  
Before And After ◽  
Binder Ratio ◽  
Cold Area ◽  
Fractal Characteristics ◽  
Water Binder Ratio

For further research on durability of concrete material under salt frozen conditions in cold area, the non air-entraining concrete with water-binder ratio of 0.4 and 0.28, air-entraining concrete with water-binder ratio 0.28 and the air content 7.0% are studied respectively. The fractal dimension of three kinds of concrete pore at different pore diameter range were determined by MIP(mereury intrusion porosimetry) before and after salt freezing and were studied in a comparative way. The research shows that the fractal dimension of pore diameter at range of 50nm ~ 550nm after salt freezing changed remarkably, namely salt frozen process has greater influence on pore within this range. Objectively the pore within this range in concrete suffered supercooled water osmotic pressure is the greatest. In addition, the total porosity reduced after salt freezing injury while fractal dimension changed more obviously. The fractal dimension of concrete pore could be a good reflection of concrete structure after salt freezing injury, showing that the diameter at 50nm ~ 550nm after salt frozen injury coarsening is obvious. Thus the fractal dimension of diameter within this range can be used as a key parameters after salt freezing injury.

scholarly journals The collaboration between the cardiologist and general practitioner – the key of post-myocardial infarction management

2015 ◽  
Vol 62 (2) ◽  
pp. 125-129
Author(s):  
Alexandru Scafa-Udrişte ◽  
◽  
Oana Tăutu ◽  
Carmen Zaharescu ◽  
Vlad Bătăilă ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Myocardial Infarction ◽  
General Practitioner ◽  
Therapeutic Strategy ◽  
The Status ◽  
Long Time ◽  
Therapeutic Measures ◽  
The One ◽  
Main Factor

The therapeutic strategy for a discharged patient who suffered a miocardial infarction implies a complexity of therapeutic measures and recommendations that guide the mid- and long-time outcome. A main factor of this process is represented by the thrust the patient has in the physician, physician being the person who prescribes and adjusts the treatment, and decides upon the investigations that need to be done. This is a dinamic process, the status of a patient who suffered a miocardial infarction being able to vary at any time during this evolution, especially in associated pathologies. The patient may be evaluated by multiple doctors, the therapeutic strategy being established by a cardiologist, general practitioner, or a team composed of cardiologist and general practitioner. However, the one who knows this best is the patient. This study is exclusively addressed to the patients (structured as a qestionnaire), future discussion being based on their answers. In this context, following the guideline recommandations concerning monitorization, recovery and the quality of life of the patient suffering from miocardial infarction, best result are obtained when the therapeutic strategy is established by a team formed from cardiologist and general practitioner.

scholarly journals Fractal Dimension of Basalt Fiber Reinforced Concrete (BFRC) and Its Correlations to Pore Structure, Strength and Shrinkage

Materials ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3238
Author(s):  
Yue Li ◽  
Aiqin Shen ◽  
Hua Wu
Keyword(s):  
Fractal Dimension ◽  
Pore Structure ◽  
Pore Size ◽  
Pore Diameter ◽  
Size Range ◽  
Basalt Fiber ◽  
Shrinkage Strain ◽  
Fiber Reinforced Concrete ◽  
Average Pore ◽  
Fractal Characteristics

In this study, we focused on exploring the correlations between the pore surface fractal dimensions and the pore structure parameters, strength and shrinkage properties of basalt fiber-reinforced concrete (BFRC). The pore structure of BFRCs with various fiber contents and fiber lengths was investigated using mercury intrusion porosimetry (MIP) measurements. Through Zhang’s model, the fractal characteristics of BFRCs in the whole pore size range and in different pore size ranges were calculated from the MIP test data. The results showed that the addition of BF increased the total porosity, total pore volume and pore area but decreased the average pore diameter, indicating that BFs refined the pore structure of the concrete. BFRC presented obvious fractal characteristics in the entire pore-size range and individual pore-size ranges; generally, the fractal dimension increased with increasing fiber content. Moreover, correlation analysis suggested that the fractal dimension of BFRC in the whole pore-size range (FD) was closely related to the fractal dimension in the macropore region (Dm) and average pore diameter (APD). The influence of pore structure factors on mechanical strength and shrinkage was studied by grey correlation theory, and the results showed that Dm showed positive correlations with strength and fracture energy, with increasing Dm tending to strengthen and toughen the concrete. An increase in fiber content and length was detrimental to reducing the drying shrinkage strain. In the transition pore region, the fractal dimension (Dt) at diameters ranging from 20 to 50 nm and shrinkage strain exhibited a highly linear relation. These results merit careful consideration in macro-property evaluation by using the pore surface fractal dimension in a specific region instead of the whole region. Finally, grey target theory was applied to evaluate the rank of the mechanical strength and shrinkage of concrete, and the results showed that the overall properties of concrete with a BF length of 18 mm and a BF content of 0.06% ranked the best.

Evaluation of the Properties of Humus Liquid of Earthworm Eisenia Foetida Obtained from Different Rachis

2017 ◽  
Vol 3 (02) ◽  
Author(s):  
Ramiro Remigio Gaibor Fernández ◽  
Abraham Adalberto Bayas Zamora ◽  
Galo Israel Muñoz Sánchez ◽  
Cristhian Adrián Rivas Santacruz
Keyword(s):  
Plant Growth ◽  
Fulvic Acids ◽  
Cattle Manure ◽  
Eisenia Foetida ◽  
Humic And Fulvic Acids ◽  
Livestock Manure ◽  
A Value ◽  
The One ◽  
Liquid Slurry

The objective of the present investigation was to evaluate the physical characteristics of the vermicompost and the quality of the purine of the red Californian (Eisenia foetida) using different substrates of feed for these worms. For this purpose, nine treatments were studied: 75% African palm rachis + 25% cattle manure, 50% African palm rachis + 50% cattle manure, 25% African palm rachis + 75% livestock manure, 50% manure of cattle, 50% of manure of cattle, 25% of manure of cattle, 50% of manure of cattle, 50% of manure of cattle, 50% of rach of coconut + 50% of manure of Livestock, 25% coccus rachis + 75% livestock manure. The substrate made up of 50% of rachis of coconut and 50% of livestock manure can be used in nurseries or nurseries for being the one that registered a value of pH 7.3 plus the closest to the neutral compared to the others, besides this (75% of oil palm rachis and 25% of cattle manure) showed a higher content of humic and fulvic acids (0.87 and 0.45 p / p, respectively), compounds that are important for agriculture by stimulating plant growth, in addition to this reflection 0.06% sulfur content, 4.0 ppm boron, 7.0 ppm copper, 47.5 ppm iron, 6.0 ppm manganese, with a presence of microorganisms of the species Trichoderma, Penicillium, Cladosporium sp. in amounts of 1.91x105 UFC / ml, however in this substrate was obtained between 13.3 and 43.5% less liquid slurry in Comparison with other treatments.

Contribution to a Magnetite Consumption in the Karviná Mine's Preparation Plant of the Lazy Plant / Příspěvek Ke Spotřebě Magnetitu Na Úpravně Dolu Karviná, Závodu Lazy

2012 ◽  
Vol 58 (2) ◽  
pp. 1-6
Author(s):  
Radim Pavlík ◽  
Vlastimil Řepka
Keyword(s):  
The One ◽  
Preparation Plant

Abstract In its introduction, this contribution deals with the usage of magnetite during the process of coal separation in the Karviná Mine's preparation plant of the Lazy Plant. Next it deals with the evaluation of quality of magnetite used in the preparation plant, losses of magnetite adhering to the products leaving the preparation plant, the recovery of a diluted suspension with focus on the efficiency of magnetite separation of the diluted suspension and the comparison of the magnetite consumption with the one in the ČSM preparation plant. In conclusions, the article presents options leading to the reduction of the magnetite consumption in the Karviná Mine's preparation plant of the Lazy plant. For comparison, the data of the ČSM Mine is stated here.

The concept of motivation for effective credit risk management

2020 ◽  
Vol 26 (11) ◽  
pp. 2567-2593
Author(s):  
M.V. Pomazanov
Keyword(s):  
Risk Management ◽  
Economic Modeling ◽  
Type I ◽  
Credit Risk Management ◽  
Curve Modeling ◽  
Business Functions ◽  
The Common ◽  
Lending Decisions ◽  
The One

Subject. The study addresses the improvement of risk management efficiency and the quality of lending decisions made by banks. Objectives. The aim is to present the bank management with a fair algorithm for risk management motivation on the one hand, and the credit management (business) on the other hand. Within the framework of the common goal to maximize risk-adjusted income from loans, this algorithm will provide guidelines for ‘risk management’ and ‘business’ functions on how to improve individual and overall efficiency. Methods. The study employs the discriminant analysis, type I and II errors, Lorentz curve modeling, statistical analysis, economic modeling. Results. The paper offers a mechanism for assessing the quality of risk management decisions as opposed to (or in support of) decisions of the lending business when approving transactions. The mechanism rests on the approach of stating type I and II errors and the corresponding classical metric of the Gini coefficient. On the ‘business’ side, the mechanism monitors the improvement or deterioration of the indicator of changes in losses in comparison with the market average. Conclusions. The study substantiates the stimulating ‘rules of the game’ between the ‘business’ and ‘risk management’ to improve the efficiency of the entire business, to optimize interactions within the framework of internal competition. It presents mathematical tools to calculate corresponding indicators of the efficiency of internally competing entities.

The Development of Agritourism in the Podkarpackie Voivodeship in the Light of International and National Conditions

2017 ◽  
Vol 13 ◽  
pp. 244-261
Author(s):  
Mariola Tracz ◽  
Małgorzata Bajgier-Kowalska ◽  
Radosław Uliszak
Keyword(s):  
Development Strategy ◽  
Current State ◽  
Central Statistical ◽  
Central Statistical Office ◽  
Tourism Resources ◽  
The One ◽  
The Impact ◽  
District Offices ◽  
Socio Economic Factors

Podkarpackie Voivodeship is one of the regions of Poland in which the number of agritourism entities is very high. Therefore tourism plays a significant role in its development strategy. The aim of the paper is to identify the current state of agritourism and the changes that have occurred in the region in the years 2000–2016. Specific objectives are to determine the distribution of agritourism farms and their offer, together with a comprehensive analysis of the environmental and socio-economic factors, as well as the impact of the Slovak-Ukrainian border. The report was developed on the statistical materials from the Polish Central Statistical Office, Podkarpackie Agricultural Advisory Centre in Boguchwała and data collected from municipalities and district offices that is published on their websites, as well as through interviews with 100 owners of agritourism farms in the Podkarpackie Voivodeship. The research has shown, on the one hand, the decline in the number of farms in the region and, on the other hand, the increase in the diversity of the tourist offer of these entities. Distribution of agritourism farms is closely linked to the attractiveness of natural environment and quality of secondary tourism resources. Traditional agritourism has not yet fully used its countryside, as well as cross-border advantages of its location.

Microscopic structure of the one-phonon 2+ states of Po208

2021 ◽  
Vol 104 (2) ◽  
Author(s):  
D. Kalaydjieva ◽  
D. Kocheva ◽  
G. Rainovski ◽  
V. Karayonchev ◽  
J. Jolie ◽  
...  
Keyword(s):  
Microscopic Structure ◽  
The One

scholarly journals Why Do Our Cancer Patients Sleep So Badly? Sleep Disorders in Cancer Patients: A Frequent Symptom with Multiple Causes

2021 ◽  
pp. 1-7
Author(s):  
Herwig Strik ◽  
Werner Cassel ◽  
Michael Teepker ◽  
Thomas Schulte ◽  
Jorge Riera-Knorrenschild ◽  
...  
Keyword(s):  
Sleep Disorders ◽  
Cancer Patients ◽  
Treatment Options ◽  
Ethics Committee ◽  
Breathing Disorders ◽  
The One ◽  
Diagnosis Therapy ◽  
The University ◽  
Insomnia Symptoms

<b><i>Introduction:</i></b> On the one hand, sleep disorders in cancer patients are reported in 30–50% of cancer patients. On the other hand, specific causes for these sleep disorders are little known. This study was done to evaluate factors which may affect sleep of cancer patients. To our knowledge, this is the first study which includes return to work as one factor of sleep disturbance. <b><i>Methods:</i></b> 107 patients with various types of cancer treated in 2 hospitals were interviewed with a battery of questionnaires after having given informed consent. The questionnaires intended to detect abnormalities of sleep and related pain, breathing disorders, restless legs syndrome, depression, rumination, medication, and psychosocial distress. The study was approved by the ethics committee of the University of Marburg. <b><i>Results:</i></b> The analysis of the 6 sleep-related questionnaires indicated a sleep disorder of any kind in 68% of all patients. Insomnia symptoms were present in 48 patients (44.9%). Pain, depression, anxiety, and worries about the workplace were significantly related to sleep disorders. <b><i>Conclusion:</i></b> Sleep disorders are common in cancer patients. The causes are manifold and should be considered by caregivers during diagnosis, therapy, and aftercare of cancer patients. Tumour patients should actively be asked about sleep disorders. If these are present, they should be addressed, and as they have a large impact on quality of life, treatment options should be offered in cooperation with sleep specialists.

scholarly journals Personality and Dementia: an Approach to Differential Profile of the Caregiver

2011 ◽  
Vol 1 (3) ◽  
pp. 85-94
Author(s):  
Elena de Andrés-Jiménez ◽  
Rosa Mª Limiñana-Gras ◽  
Encarna Fernández-Ros
Keyword(s):  
Relevant Information ◽  
Personality Profile ◽  
Family Carers ◽  
Psychological Variables ◽  
People With Dementia ◽  
The Family ◽  
Study Population ◽  
The One ◽  
The Impact

The aim of this study is to determine the existence of a characteristic personality profile of family carers of people with dementia. The correct knowledge and use of psychological variables which affect the carer, helps to promote appropriate actions to mitigate the impact of care and improve the carer’s quality of life and likewise the one of the person cared for. The study population consists of 69 family carers of people with dementia, members of various associations and care centers. The results allow us to identify a characteristic personality profile for these carers and it reveals a specific psychological working in this sample, although we cannot directly relate it with the tasks of caring for people with this disease, this profile gives us very relevant information to pay more attention to the needs of this group. Moreover, the analysis of personality styles depends on the sex of the family carer, showing, once again, that the woman is in a situation of most vulnerability.

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