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EN
Ozone is known as a "god-given purifying agent", and its quantitative detection is of great significance. A low-cost photoacoustic spectroscopy (PAS) which is based on absorption at the low-power blue diode emitting at 403.65 nm has been used for nitrogen oxide (NO2) concentration measurements. According to the formula of nitric oxide (NO) reaction and ozone (O3) production of NO2 and the differential detection method, a dual-channel PAS system for O3 detection is reported. The consistency of NO2 detection with the dual-channel photoacoustic spectroscopy system is good by contrast. The coefficient of determination R2 can still reach 0.846. An intercomparison between the system and a cavity ring-down system (CRDS) was shown to verify the accuracy. The results showed a linear correction factor (R2) of 0.943 in a slope of 0.862±0.002, with an offset of (0.773±0.128) ppb. In addition, the measurement of O3 using the dual-channel cavity photoacoustic spectroscopy technique was deployed. These observations indicate that O3 concentrations can be effectively observed with the dual-channel PAS instrument.
EN
Fenton reaction is an important method to remove NO from flue gas. •OH radicals generated in the Fenton reaction can effectively oxidize NO to NO2, which is absorbed and removed by alkali sorbent. To supply guidance for engineering research, numerical simulation of NO oxidation by •OH radical clusters in flue gas has been carried out using Fluent software. The average concentration of NO on the cross sections at various positions of a cylindrical pipe with a circular surface was calculated by simulation. Under various working conditions (temperature, •OH/NO molar ratio, NO concentration in flue gas, and jet velocity), NO oxidation efficiency by •OH radical was simulated and the key factors affecting NO oxidation were analyzed. The results show that temperature and •OH/NO molar ratio are the key factors affecting the oxidation of NO by •OH radicals. The injection velocity has also a significant effect on the oxidation efficiency while the moisture and oxygen content are minor factors influencing the process. The optimum oxidation efficiency of NO is obtained at 473–523 K, the molar ratio of •OH/NO ca. 1.4, the jet velocity 10 m/s, and the flue gas velocity of 3 m/s.
EN
To reduce the emission of nitrogen oxides (NOx) during the co-disposal of sludge in a TTF-type precalciner, an optimized co-disposal process of a TTF-type precalciner has been implemented in a cement plant in Hebei. The model was built using ANSYS FLUENT software. The effects of three single-factor perspectives (sludge input ratio, gas flow rate, and tertiary air temperature on NO concentration) were investigated. The response surface method of Box–Behnken design was used. When the sludge ratio increased from 0 to 25%, the NO concentration at the outlet was 122–297 mg/m3. Meanwhile, it increased from 192 mg/ m3 to 241 mg/ m3 since the airflow increased from 95 m3/s to 122 m3/s. The maximum NO concentration was 192 mg/ m3 when the tertiary air temperature was 1170 K. The inter-action between airflow and sludge ratio was more significant than any other interaction between other conditions (P < 0.05). Finally, the optimum conditions were a sludge ratio of 5%, airflow 109 m3/s, and tertiary air temperature 1280 K. NO concentration was 166.9 mg/m3 under this condition.
PL
Podczas 104. posiedzenia Międzyresortowej Komisji ds. Najwyższych Dopuszczalnych Stężeń i Natężeń Czynników Szkodliwych dla Zdrowia w Środowisku Pracy (dalej: Międzyresortowa Komisja ds. NDS i NDN), które odbyło się 16 marca 2023 r., rozpatrywano m.in. propozycje wartości dopuszczalnych stężeń dla trzech nowych substancji: 1,2-dihydroksybenzenu, kwasu benzoesowego oraz N-nitrozodipropyloaminy.
PL
Buraki stanowią źródło wielu związków prozdrowotnych, o dobrze udokumentowanym wpływie na zdrowie człowieka. Ich działanie terapeutyczne jest zdeterminowane obecnością nieorganicznych związków azotu, flawonoidów, betalain, będących naturalnymi barwnikami, a także wybranych witamin i związków mineralnych. Aktualny stan wiedzy dowodzi, że buraki są szczególnie cenne dla układu krążenia. Wynika to z ich właściwości hipotensyjnych, jak również działania zmniejszającego sztywność tętnic. Co więcej buraki wykazują działanie krwiotwórcze, poprawiają funkcjonowanie mózgu, redukują stężenie glukozy we krwi, a także charakteryzują się właściwościami hepatoprotekcyjnymi.
EN
Beets are a source of many health-promoting compounds with a well-documented impact on human health. Their therapeutic effect is determined by the presence of inorganic nitrogen compounds, flavonoids, betalains, which are natural dyes, as well as selected vitamins and minerals. The current state of knowledge proves that beetroot is especially valuable for the circulatory system. This is due to their antihypertensive properties as well as reducing arterial stiffness. Moreover, beetroot has a hematopoietic effect, improves the functioning of the brain, lowers the level of blood glucose, and is also characterized by hepatoprotective properties.
EN
With rapid economic development and industrialization, air pollution is becoming a critical global issue affecting health. Sulfur dioxide and nitrogen oxides are the major contributors to acid rain and the key indicators for evaluating atmospheric pollution. And source intensity and meteorological factors are the main ways to influence the concentrations of sulfur dioxide and nitrogen oxides. Thus, to investigate the specific effects of source intensity, temperature, humidity, wind speed and atmospheric pressure on SO2 and NOx, the path analysis method was used for the model. The results showed that Source intensity significantly affects the concentrations of SO2and NO2. For both NO2 and SO2, the source intensity accounted for around 40%. Meteorological factors have very limited effects on the concentrations of SO2and NO2. The effects of the meteorological factors on air pollutants are specific as differences in material properties. Humidity significantly affects the concentration of SO2while temperature, humidity and wind speed have significantly affected the concentration of NO2.
7
Content available remote Kompozyty cementowe modyfikowane węglem aktywnym
PL
Współczesny rozwój cywilizacyjny ma negatywny wpływ na otaczające nas środowisko. Jest to szczególnie zauważalne na terenach zurbanizowanych, gdzie występuje intensywne zanieczyszczenie nie tylko gleby, wody, ale przede wszystkim powietrza. Wśród zanieczyszczeń gazowych należy zwrócić szczególną uwagę na tlenki azotu (popularnie oznaczane jako NOx). W artykule przedstawiono wyniki wstępnych badań laboratoryjnych nad zastosowaniem dodatku węgla aktywnego do modyfikacji kompozytów cementowych. Potwierdziły one korzystne efekty zastosowania tego dodatku w celu zwiększenia efektywności pochłaniania tlenków azotu. Proponowana technologia ma tę przewagę nad cementami z dodatkiem TiO2, że nie wymaga aktywacji promieniowaniem UV. Z tego powodu kompozyty cementowe modyfikowane węglem aktywnym mogą być zastosowane w garażach, przejściach podziemnych czy tunelach.
EN
Contemporary civilization development has a negative impact on the surrounding environment. It is especially noticeable in urbanized areas where there is intense pollution not only of soil and water, but most of all air. Among the gaseous pollutants, particular attention should be paid to nitrogen oxides (commonly written as NOx). The results of preliminary research on the use of the addition of activated carbon for the modification of cement composites are presented in the article. The obtained results of laboratory tests confirmed the beneficial aspects of using this additive in order to increase the efficiency of nitrogen oxide adsorption by cement composites. The proposed technology complements the hitherto used cements with the addition of TiO2. However, it has the advantage that it does not require activation by UV radiation. Hence, cementitious composites modified with activated carbon can be used in garages, underground passages and tunnels.
EN
Arterial blood flow waveform shape (ABFWS) analysis is usually employed in vessels diagnosis. This review presents links between ABFWS and some other physiological and psychological aspects. ABFWS for brachial and common carotid arteries is quantified with a Waveform Age (WA) index. WA well correlates with calendar age (CA): r = 0.79 and 0.88 for carotid and brachial arteries, respectively. The mean (expected) WA for a particular CA is equal to it. WA depends on blood flow wave reflections: WA is older for lower reflections (smaller flow pulsatility). An upper death limit of WA seems to exist; hypertension in the elderly may be a defense mechanism protecting against exceeding this limit. Relationships between WA and heart rate, fatigue and cognitive functions are most interesting. Regardless of breathing pattern, respiratory induced changes of heart rate are strongly correlated with WAs that were 1.7 s earlier (r = 0.87). Fatigue is associated with WA increase (p < 0.002); in a way, fatigue accompanies aging or temporary mimics it. WA is significantly lower than CA in persons with high intelligence quotient and significantly higher in patients with intellectual disability of unknown etiology (p < 0.000001). WA relatively well correlates with Matrices Tests scores (r = 0.65 for a linear combination of WAs for all the four arteries; 42 students, 16 yrs, the same social and educational levels). ABFW-Sdependent production of vasoactive substances (including nitric oxide being also a neurotransmitter) by endothelium, might be responsible for those surprising relationships. ABFWS can be treated, though only to some extent, as a kind of Damasio’s somatic markers.
10
Content available Nowotwory kości : nowe możliwości terapeutyczne
EN
Among bone tumours, Osteosarcoma (OS), Chondrosarcoma (CS) and Fibrosarcoma (FS) are highly metastatic with poor prognostic for survival. Standard procedures as surgery resection, radiotherapy and chemotherapy do not lead to full recovery or they do not affect metastasis [1-4]. Nowadays new molecular targets to cure cancer are during clinical trials. Clinical trials for OS are focused on using monoclonal antibody (dinutuximab) [5], immunotherapy (as using GM-CSF with influence on white blood cells) [6] or compounds acting as VEGFR inhibitor or PDGFR inhibitor - to reduce metastasis [7-9]. Clinical trials for CS are targeting the hedgehog pathway, focused on its inhibition [10], inhibition of IDH1/2 (common mutation in CS leading to hypermethylation) [11] or, as in OS treatment, inhibition of metastasis by acting on VEGFR [12]. Beyond new chemotherapy and chemotherapy correlated with radiotherapy [13] clinical trials for FS are targeting gene fusion NTRK acting through inhibition of tropomyosin kinase receptor [14]. This approach to treatment is a novelty on the global scale [15]. Nitric oxide (NO) has many biological functions, e.g.: acting as neurotransmitter, reduced aggregation of platelets, acting as EDRF or reducing the oxidative stress in tumours [16-18]. Due to the dual nature of NO [19] anti-proliferative, pro-apoptotic and cell cycle arrest effect of NO were observed [20-25]. It could be a new area to find novel anti-cancer compound. One of the molecular targets under the scientists consideration is the activation of nitric oxide synthase (NOS). Górska-Ponikowska et al. [26-28] focused on experiments on OS 143B cells with 2-methoxyestradiol (2-ME) treatment, potentially novel compound playing the role of n-NOS activator. The researchers reported influence of 2-ME on down-regulation of mitochondrial biogenesis via direct influence on n-NOS level in OS 143B cells. What is more, L-lactate was indicated as potential molecular marker of anticancer therapy of tumours with metastasis.
PL
Opracowano multiplikatywny model matematyczny pozwalający opisać przebieg procentowej (względem średniej globalnej) cyklicznej zmienności stężenia NO2 w powietrzu. Stwierdzono, że zbudowany matematyczny model regresji, uwzględniający parametry cykliczności związane z porą dnia, tygodnia i roku, w 26,7% wyjaśnia zmienność stężenia NO2 w atmosferze w badanym środowisku miejskim.
EN
To continue the former study on NOx concn. in town air (Sz. Ignaciuk et al., 2019), the NO2 concn. under the same conditions was performed. Cyclicity of the NO2 concn. changes (time of a day, day of a week and month of a year) was math. modelled. The model explained 26.7% of the obsd. changes.
PL
Ustalono zasady cyklicznej zmienności zawartości NOx w powietrzu w zależności od czasu. Pomiary prowadzono co 1 h przez 7 lat na wybranej stacji w Europie Środkowej. Zbudowany model regresji uwzględniający parametry cykliczności związane z porą dnia, tygodnia i roku w ok. 11,4% wyjaśniał zmienność zawartości NOx w atmosferze. Po uzupełnieniu tego modelu regresji tylko jednym odchyleniem standardowym uzyskano aż 89,9-proc. obszar ufności prognozy dla stężenia NOx.
EN
Data of NOx content in air in a large city located in the south-eastern Poland were measured in 1 h intervals from January 2011 to December 2017 to develop a math. model of the course of the pollution changes. The content of NOx in air varied significantly in the time of a day, day of a week and month of a year. The model explained 11.4% of the obsd. changes in NOx concn.
PL
W artykule opisano wyniki badań dotyczące emisji limitowanych składników spalin z jednocylindrowego, badawczego silnika firmy AVL serii 5402 zasilanego mieszaninami oleju rzepakowego i eteru dietylowego. W badaniach wykorzystano olej rzepakowy do którego dodano 10, 20, 30 i 40 % objętościowo eteru dietylowego. Oceniono właściwości fizykochemiczne przygotowanych mieszanin paliwowych i ich wpływ na emisję limitowanych składników spalin, a w szczególności cząstek stałych, tlenków azotu oraz niespalonych węglowodorów. Stwierdzono, że dodatek DEE do oleju rzepakowego sprzyja zmniejszeniu emisji szkodliwych składników spalin do otoczenia, a w szczególności cząstek sadzy oraz niespalonych węglowodorów. Eter dietylowy dodany do oleju rzepakowego nie ma istotnego znaczenia na zmianę emisji tlenków azotu. Wskazany problem stanowi barierę typową dla procesu spalania paliwa i w niewielkim stopniu jest zależny od jego rodzaju. Mając to na uwadze należy stwierdzić, że ograniczenie emisji NOx do otoczenia wymaga zmiany spalania paliwa w kierunku realizacji tzw. procesu niskotemperaturowego. W konwencjonalnych systemach spalania redukcja emisji NOx w dalszym ciągu będzie wymagała stosowania dodatkowych układów oczyszczających jak np. SCR tj. selektywna redukcja katalityczna.
EN
The paper describes the results of research on the emission of limited exhaust components from a single-cylinder, research engine of the AVL series 5402 powered by mixtures of rapeseed oil and diethyl ether. Rapeseed oil was used in the research, to which 10, 20, 30 and 40% by volume of diethyl ether was added. The physicochemical properties of the prepared fuel mixtures and their impact on the emission of limited exhaust components, in particular particulates, nitrogen oxides and unburned hydrocarbons, were evaluated. It was found that the addition of DEE to rapeseed oil helps to reduce the emission of harmful exhaust components to the environment, in particular soot particles and unburned hydrocarbons. Diethyl ether added to rapeseed oil has no significant effect on changing the emission of nitrogen oxides. The indicated problem is a barrier typical of the fuel combustion process and is slightly dependent on its type. With this in mind, it should be noted that reducing NOx emissions to the environment requires a change in fuel combustion towards the implementation of the so-called low temperature process. In conventional combustion systems, the reduction of NOx emissions will still require the use of additional treatment systems such as SCR, i.e. selective catalytic reduction.
PL
W pracy przedstawiono wyniki wstępnych badań nad efektywnością ograniczenia stężenia tlenków azotu w gazach odlotowych z instalacji wypalania klinkieru metody suchej z długim piecem obrotowym przy wykorzystaniu nadtlenku wodoru o stężeniu 30%. Badania przeprowadzono na doświadczalnej instalacji o przepustowości gazów wynoszącej 5000 m3n/h, przy temperaturze na wejściu do instalacji ok. 170°C i wilgotności gazów na poziomie 3–4%. Podczas badań w sposób ciągły kontrolowano parametry gazu, takie jak: strumień gazów, temperatura, skład gazów. Efektywność usuwania NOx z gazów wynosiła od 10 do 60%. Podstawowe czynniki wpływające na tę efektywność to strumień masy dozowanego nadtlenku wodoru oraz skład oczyszczanych gazów.
EN
This paper presents the results of preliminary research on efficiency of nitrous oxides concentration reduction in exhaust gases from long dry kiln using 30% hydrogen peroxide solution. Research was conducted on an experimental installation with a gas throughput of 5000 nm3/h at the gas inlet temperature of 170°C and gas moisture of 3–4%. During the tests parameters such as: gas flow rate, temperature and gas composition were monitored constantly. The efficiency of removing NOx from exhaust gases was from 10 to 60%. Primary factors influencing this efficiency are mass flow rate of hydrogen peroxide and composition of exhaust gas.
EN
Cryosurgery is a procedure in which diseased tissue is destroyed by freezing. During a strictly controlled process, low temperature is used to separate diseased from healthy tissue with minimal bleeding. It is an effective method that has been applied in many areas of medicine for a number of years, especially in dermatology, oncology, laryngology, gynecology, vascular surgery and ophthalmology. There are many technical solutions different probes for applying low temperature to tissue. The detailed construction of the probes are trade secrets and will not be discussed here. In the paper the authors present the results of research on a chosen type of cryosurgical probe for various conditions: feeding gases, flow rates and external conditions. The results are illustrated in the form of graphs showing the temperature of the tip of the probes in changing conditions.
EN
This paper presents a way of predicting NOx emissions from circulating fluidized bed combustors (CFBC) in air-fired and oxyfuel conditions, using the Artificial Neural Network (ANN) Approach. The Original Neural Networks Model was successfully applied to calculate the NOx (i.e. NO + NO2) emissions from coal combustion under air-fired and oxygen-enriched conditions in several CFB boilers. The ANN model was shown to give quick and accurate results in response to the input pattern. The NOx emissions, evaluated using the developed ANN model are in good agreement with the experimental results.
EN
Examinations were carried out to investigate the effectiveness of natural zeolite clinoptilolite and its thermally activated and modified forms in decreasing the concentration of nitrogen oxides, the frequently monitored components of the environment, in automobile exhaust gases. Since nitrogen oxides contribute to the greenhouse effect, the public increases pressure on motor vehicle manufacturers to intensify their efforts toward the reduction of the relevant emissions. One option is the use of a combination of a conventional three-way catalytic converter with either a synthetic or modified natural zeolite. Researchers and designers are coming up with new solutions, which are protected by patents. In this study, natural zeolite clinoptilolite (grain size 5–8 mm) and its thermally treated (270°C, 2 hours) and modified forms (ammonia, cobalt) were used in the form of filters. The results of our measurements showed high the effectiveness of the tested forms which are relatively easy to prepare and are economically advantageous in comparison with the synthetic alternatives. The heat treated and ammonia forms decreased the concentration of nitrogen oxides in the exhaust gases by 31% and 59%, respectively. The cobalt form appeared prospective as it exhibited not only adsorption but also catalytic properties which are effective in decreasing nitrogen oxides emissions. After initial stabilization, its effectiveness did not change with time. With this modification, 46.4% reduction in nitrogen oxide emissions was achieved.
PL
Badania przeprowadzono w celu zbadania skuteczności naturalnego zeolitu klinoptylolitu aktywowanego termicznie i w zmodyfikowanej formie do zmniejszania stężenia tlenków azotu w gazach spalinowych samochodów. Ponieważ tlenki azotu przyczyniają się do zwiększenia efektu cieplarnianego, społeczeństwo zwiększa presję na producentów samochodów do wzmożenia wysiłków w kierunku redukcji emisji gazów cieplarnianych. Jedną z możliwości jest stosowanie kombinacji konwencjonalnej trójdrogowego konwertora katalitycznego albo z syntetycznych lub naturalnych modyfikowanych zeolitów. Obecnie znane są nowe rozwiązania, które jednak chronione są patentami. W tym badaniu, naturalny zeolit klinoptylolit (wielkość ziarn 5−8 mm) po obróbce cieplnej (270°C, 2 godziny) i zmodyfikowaniu formy (amoniak, kobalt) użyto w postaci filtrów. Wyniki pomiarów wykazały wysoką skuteczność badanych form, które są stosunkowo łatwe do wytworzenia i są korzystne ekonomicznie w porównaniu z syntetycznymi alternatywami. Obróbka zeolitu ciepłem i amoniakiem zmniejszyła stężenia tlenków azotu w gazach odlotowych odpowiednio o 31 i 59%. Zeolit modyfikowany kobaltem wykazywał nie tylko adsorpcję, ale również właściwości katalityczne, które są skuteczne w zmniejszaniu emisji tlenków azotu. Po wstępnej stabilizacji, jego skuteczność nie zmienia się w czasie. Dzięki tej modyfikacji, redukcja 46,4% emisji tlenków azotu została osiągnięta.
EN
Aggregation of red blood cells in the micro vasculature may affect blood viscosity in the vessel. The purpose of this study was to investigate the potential effect of non-uniform viscosity caused by red blood cell (RBC) aggregation on nitric oxide (NO) concentration and distribution. A 3-D multi-physics model was established to simulate the production, transport and consumption of NO. Two non-uniform viscosity models caused by RBC aggregation were investigated: one assuming a linear and the other a step hematocrit distribution. In addition, the effect of the thickness of the plasma layer was tested. Simulation results demonstrate that non-uniform viscosity caused by RBCs aggregation influences NO concen-tration distribution. Compared with the uniform viscosity model, NO concentration using non-uniform viscosity is lower than that using uniform viscosity. Moreover, NO concentration calculated from the step hematocrit model is higher than that calculated from the linear hematocrit model. NO concentrations in the endothelium and the vascular wall decrease with the decline of the thickness of the plasma layer. The relative decrease differs between the linear and the step model. Our results suggest that non-uniform viscosity caused by red blood cell aggregation affects nitric oxide distribution in the micro vasculature. If uniform viscosity is assumed when performing numerical simulations, NO concentration values may be overestimated.
19
Content available remote Katalityczne oczyszczanie spalin z kotłów małej mocy
PL
Przeprowadzono badania rozkładu temperatury na powierzchni deflektora w retortowym kotle małej mocy zasilanym peletem drzewnym. Spreparowano katalizatory wanadowe osadzone bezpośrednio na podłożu deflektora oraz na krzemionkowej warstwie pośredniej o zawartości wanadu 20,1 g/m² deflektora. Ponadto spreparowano katalizator platynowy o warstwie pośredniej z Al₂O₃ o zawartości platyny 0,08 g/m² deflektora. Oznaczono stężenia CO oraz NOx w spalinach emitowanych z kotła podczas rozruchu oraz pracy z mocą nominalną. Efektem działania katalizatorów było zmniejszenie zawartości NOx do ok. 8%.
EN
Temp. distribution on the surface of the deflector in a retort small power boiler supplied with wood pellet was studied. Two V₂O₅ catalysts were deposited directly on the deflector surface or intermediately on SiO₂ carrier and one Pt catalyst was deposited on an intermediate Al₂O₃ layer. The exhaust gases were studied for CO and NOx contents. Use of the catalysts resulted in redn. of NOx with CO or hydrocarbons present. The deflector-supported V₂O₅ catalyst was the most efficient.
PL
W artykule przedstawiono wyniki weryfikacji konkluzji BAT 20, 22 i 23 dla spiekalni rud. Badania przeprowadzono na linii do półprzemysłowej symulacji procesu spiekania rud żelaza, będącej na wyposażeniu Zakładu Badań Procesów Surowcowych Instytutu Metalurgii Żelaza. Stwierdzono, że możliwe jest spełnienie tych konkluzji BAT. Dzięki właściwościom wkładów ceramicznych pokrytych katalizatorem V2O5/TiO2 uzyskano prawie 100% redukcję pyłów i SOx oraz około 60% redukcję NOx ze spalin.
EN
The paper presents the results of the verification of BAT conclusions 20, 22 and 23 for the sinter plants. The research was carried out on a line for semi-industrial simulation of iron sintering at the Department of Primary Processes of the Institute for Ferrous Metallurgy. Based on the obtained data, it was found that it is possible to realise these BAT conclusions. Owing to the properties of ceramic inserts coated with a V2O5/TiO2 catalyst nearly 100% reduction of particulate matter and SOx, as well as about 60% reduction of NOx from flue gas were achieved.
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