The Research of CFB Boiler Operation for Oxygen Enhanced Dried Lignite Combustion

The paper presents the research of CFB boiler operation for oxygen-enhanced dried lignite combustion. The combustion in oxygen-enhanced conditions generally leads to reducing the emissions of CO and NOx and N2O due to reduced volume of flue gas. The maximum oxygen content for oxygen-enhanced combustion in O2/N2 conditions should not exceed 60%, however, the maximum drying extent of fuel should not be higher than 50% of the initial moisture content in an examined lignite

The Research of CFB Boiler Operation for Oxygen Enhanced Dried Lignite Combustion

ABSTRACT The paper presents the research of CFB boiler operation for oxygen-enhanced dried lignite combustion. The combustion in oxygen-enhanced conditions generally leads to reducing the emissions of CO and NO x and N 2 O due to reduced volume of flue gas. The maximum oxygen content for oxygen-enhanced combustion in O 2 /N 2 conditions should not exceed 60%, however, the maximum drying extent of fuel should not be higher than 50% of the initial moisture content in an examined lignite

First experience in operation of cold model of fb-clc-sf (fluidized-bed chemical-looping-combustion solid-fuels) facility

The first experiences with the cold model of dual fluidized bed unit designed for chemical looping combustion of solid fuels (FB-CLC-SF) will be presented. The constructed facility combines two different type reactors. The first one, which is the Air Reactor (AR) is operated in a regime of fast fluidized bed, whereas, the second one, which is the Fuel Reactor (FR) works under bubbling fluidized bed conditions. However, the integrated reactors make the whole construction being a CFB-type (Circulating Fluidized Bed) unit. The facility is made entirely of transparent material (Plexiglas). This feature supports effectively the measurements, which enables to conduct the comprehensive studies in the field of investigations. During this research, the air was used for bed fluidization in both reactors. As an inventory, the round glass beads were employed, since they size and density relate closely to the properties of the oxygen carriers developed concurrently in the project, whereas they are significantly less expensive and friendlier in use. Over a dozen ports for pressure measurements are provided along the main circulation path of the solids. These experimental data enable to determine the pressure balance around the whole CFB loop, which becomes the starting point for further studies. The cold simulations of solids flow demonstrate the conditions that are expected in the case of the hot 5 kW test rig operation, which remains under construction. Therefore, the main goal of this work and the challenge as well are to establish the operating conditions that consider both: a smooth fluidization throughout the FB-CLC-SF unit and an efficient oxidation/reduction of oxygen carriers in AR and FR, respectively. Moreover, these studies support directly the modelling work (Submitted paper: A 1.5D model of a laboratory scale fluidized bed CLC equipment), which makes the whole investigations being complementary

Wewnątrznaczyniowe leczenie tętniaków naczyń mózgowych przy użyciu spirali odczepianych hydraulicznie

Background: Authors analysed results of endovascular treatment using platinum hydraulically detachable coils in ruptured and unruptured cerebral aneurysms. The aim of the study was to evaluate the efficacy of the presented method and safety of the treatment for patients with cerebral aneurysms. Material/Methods: Authors describe a clinical analysis in a group of 129 patients with 153 cerebral aneurysms treated with endovascular embolization in Department of Neurosurgery and Neurotraumatology of University of Medical Sciences in Poznań, Poland. 116 patients were hospitalized with a history of subarachnoidal hemorrhage, while 13 patients were without previous onset of bleeding. In bled group the clinical condition was assessed according to Hunt-Hess's scale. All patients were treated using Balt (MDS Pression) hydraulically detachable coils system. Based on angiographic examination results one evaluated the anatomical conditions of the aneurysm, its size, and relationship of the aneurysmal sac to its neck. Considering 116 patients with ruptured aneurysms, endovascular embolization within 72 hours was performed in 70 cases, in case of 46 patients the procedure was delayed. Results: Complete occlusion of the lumen of the aneurysmal sac was achieved in 126 (82.3%) patients, while incomplete occlusion in 27 (17.7%). The efficacy of embolization was connected with the size and morphology of the aneurysm, as well as the relationship of the neck to the aneurysmal sac. Complete embolization was obtained specially in case of small aneurysms and those with a narrow neck. Conclusions: Authors proof justness of transarterial embolisation as a highly effective first choice procedure of aneurismal sack exclusion from cerebral circulation

Puffed cereals with added chamomile – quantitative analysis of polyphenols and optimization of their extraction method

Introduction Functional food plays an important role in the prevention, management and treatment of chronic diseases. One of the most interesting techniques of functional food production is extrusion-cooking. Functional foods may include such items as puffed cereals, breads and beverages that are fortified with vitamins, some nutraceuticals and herbs. Due to its pharmacological activity, chamomile flowers are the most popular components added to functional food. Objective. Quantitative analysis of polyphenolic antioxidants, as well as comparison of various methods for the extraction of phenolic compounds from corn puffed cereals, puffed cereals with an addition of chamomile (3, 5, 10 and 20%) and from Chamomillae anthodium. Material and Methods Two modern extraction methods – ultrasound assisted extraction (UAE) at 40oC and 60oC, as well as accelerated solvent extraction (ASE) at 100oC and 120oC were used for the isolation of polyphenols from functional food. Analysis of flavonoids and phenolic acids was carried out using reversed-phase high-performance liquid chromatography and electrospray ionization mass spectrometry (LC-ESI-MS/MS). Results and Conclusions For most of the analyzed compounds, the highest yields were obtained by ultrasound assisted extraction. The highest temperature during the ultrasonification process (60oC) increased the efficiency of extraction, without degradation of polyphenols. UAE easily arrives at extraction equilibrium and therefore permits shorter periods of time, reducing the energy input. Furthermore, UAE meets the requirements of ‘Green Chemistry

The Effect of Boron Content on Wetting Kinetics in Si-B Alloy/h-BN System

In this work, the effect of boron content on the high-temperature wetting behavior in the Si-B alloy/h-BN systems was experimentally examined. For this reason, hypoeutectic, eutectic and hypereutectic Si-B alloys (Si-1B, Si-3.2B and Si-5.7B wt.%, respectively) were produced by electric arc melting method and then subjected to sessile drop/contact heating experiments with polycrystalline h-BN substrates, at temperatures up to 1750 °C. Similar to pure Si/h-BN system, wetting kinetics curves calculated on a basis of in situ recorded drop/substrate images point toward non-wetting behavior of all selected Si-B alloy/h-BN couples. The highest contact angle values of ~ 150° were obtained for hypoeutectic and eutectic Si-B alloys in the whole examined temperature range. © 2018, The Author(s)

Physical Activity, Aerobic Capacity, and Total Antioxidant Capacity in Healthy Men and in Men with Coronary Heart Disease

Objective. The purpose of the study was to assess total antioxidant capacity (TAC) of blood serum in relation with habitual leisure time physical activity (LTPA) and aerobic capacity in a group of 90 men with coronary heart disease (CHD) aged 34.8–77.0 years and in 90 age-matched peers without CHD. Methods. Two spectrophotometric methods were applied to assess TAC: Ferric Reducing Ability of Serum (TAC-FRAS) and 2.2-diphenyl-1-picryl-hydrazyl (TAC-DPPH) tests. Aerobic capacity was expressed as physical working capacity at 85% of the maximal heart rate (PWC85%HRmax). Results. CHD patients had higher values of TACFRAS (1.37±0.28 versus 1.27±0.23 mmol FeCl2·L−1; P<0.05) but there were no group differences for TAC-DPPH and for uric acid (UA). Negative correlation was found between LTPA (also when calculated per kg of body mass) and TAC-DPPH in CHD patients. In CHD patients, TAC-FRAS and UA were lower in subjects with higher aerobic capacity expressed as PWC85%HRmax/kg. Those associations were not found in healthy men. Conclusions. We conclude that TAC of blood serum is moderately adversely related to LTPA and aerobic capacity in patients with CHD. UA, as the main determinant of serum TAC, may be partially responsible for those associations

Modelling of SO2 and NOx Emissions from Coal and Biomass Combustion in Air-Firing, Oxyfuel, iG-CLC, and CLOU Conditions by Fuzzy Logic Approach

Chemical looping combustion (CLC) is one of the most advanced technologies allowing for the reduction in CO2 emissions during the combustion of solid fuels. The modified method combines chemical looping with oxygen uncoupling (CLOU) and in situ gasification chemical looping combustion (iG-CLC). As a result, an innovative hybrid chemical looping combustion came into existence, making the above two technologies complementary. Since the complexity of the CLC is still not sufficiently recognized, the study of this process is of a practical significance. The paper describes the experiences in the modelling of complex geometry CLC equipment. The experimental facility consists of two reactors: an air reactor and a fuel reactor. The paper introduces the fuzzy logic (FL) method as an artificial intelligence (AI) approach for the prediction of SO2 and NOx (i.e., NO + NO2) emissions from coal and biomass combustion carried out in air-firing; oxyfuel; iG-CLC; and CLOU conditions. The developed model has been successfully validated on a 5 kWth research unit called the dual fluidized bed chemical looping combustion of solid fuels (DFB-CLC-SF)

Long-term outcome of rotational atherectomy according to burr-to-artery ratio and changes in coronary artery blood flow: Observational analysis

Background: Rotational atherectomy (RA) has been proven to be efficient for the treatment of calcified and diffuse coronary artery lesions. However, the optimal burr-to-artery ratio (BtAR) remains unidentified as well as an influence of change in blood flow on long-term outcome. Aim of our study was to examine the association between long-term outcome, and both BtAR and change in coronary flow during RA. Methods: We conducted a retrospective study including patients who underwent RA. Two independent observers calculated BtAR, pre- and postprocedural corrected Thrombolysis in Myocardial Infarction (TIMI) Frame Count (cTFC) for artery treated with RA. The long-term outcome was defined as all-cause mortality.   Results: Receiver operating characteristic (ROC) curve analysis of BtAR determined threshold of 0.6106 for all-cause mortality detection with sensitivity 50.0%, specificity 90.8%, and area under the curve (AUC) 0.730 (p &lt; 0.001). Kaplan-Meier survival analysis showed that the all-cause mortality rate in the group with the BtAR &gt; 0.6106 is significantly higher compared to the patients with lower BtAR (hazard ratio [HR] 3.76, 95% confidence interval [CI] 1.51–9.32; p &lt; 0.001). Kaplan-Meier survival analysis revealed that the all-cause mortality rate in the group with impairment in coronary flow was significantly higher compared to group with cTFC difference ≤ 0 after RA (HR 3.28, 95% CI 1.56–9.31; p = 0.02). Conclusions: BtAR &gt; 0.6106 is associated with worse prognosis of patients treated with RA. Patients showing post-RA impairment in blood flow in the target artery have worse prognosis

Association between polymorphisms in the SOX9 region and canine disorder of sex development (78,XX; SRY-negative) revisited in a multibreed case-control study

Testicular or ovotesticular disorders of sex development (DSD) in individuals with female karyotype (XX) lacking the SRY gene has been observed in several mammalian species, including dogs. A genetic background for this abnormality has been extensively sought, and the region harboring the SOX9 gene has often been considered key in canine DSD. Three types of polymorphism have been studied in this region to date: a) copy number variation (CNV) in a region about 400 kb upstream of SOX9, named CNVR1; b) duplication of SOX9; and c) insertion of a single G-nucleotide (rs852549625) approximately 2.2 Mb upstream of SOX9. The aim of this study was thus to comprehensively analyze these polymorphisms in a large multibreed case-control cohort containing 45 XX DSD dogs, representing 23 breeds. The control set contained 57 fertile females. Droplet digital PCR (ddPCR) was used to study CNVR1 and the duplication of SOX9. Fluorescent in situ hybridization (FISH) was used to visualize copy numbers on a cellular level. The Sanger sequencing approach was performed to analyze the region harboring the G-insertion. We confirmed that CNVR1 is highly polymorphic and that copy numbers varied between 0 and 7 in the case and control cohorts. Interestingly, the number of copies was significantly higher (P = 0.038) in XX DSD dogs (mean = 2.7) than in the control females (mean = 2.0) but not in all studied breeds. Duplication of the SOX9 gene was noted only in a single XX DSD dog (an American Bully), which had three copies of SOX9. Distribution of the G-nucleotide insertion was similar in the XX DSD (frequency 0.20) and control (frequency 0.14) cohorts. Concluding, our study showed that CNVR1, located upstream of SOX9, is associated with the XX DSD phenotype, though in a breed-specific manner. Duplication of the SOX9 gene is a rare cause of this disorder in dogs. Moreover, we did not observe any association of G-insertion with the DSD phenotype. We assume that the genetic background of XX DSD can be different in certain breeds