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1
Content available remote Analiza wybranych konstrukcji wielozłożowego adsorpcyjnego układu chłodniczego
PL
Omówiono budowę i funkcjonowanie prostego, jednozłożowego adsorpcyjnego układu chłodniczego. Dokonano analizy wybranych konstrukcji układów wielozłożowych. Zweryfikowano opracowany prototyp własnego rozwiązania systemu adsorpcyjnego. Zaprezentowano przykładowe wyniki z weryfikacji układu, dla którego osiągnięto temperaturę w parowniku na poziomie ok. 6°C. Innowacyjnym elementem tego układu był kształt prototypowych adsorberów ze stali nierdzewnej, które są wykonane jako dwa różne rozwiązania konstrukcyjne: walcowo-krzyżowy i walcowo-rurowy. Prezentowane systemy adsorpcyjne, ze względu na swoje parametry pracy, mogą być wykorzystywane do zagospodarowania niskotemperaturowego ciepła odpadowego w przemyśle.
EN
The construction and operation of a simple single-bed adsorption refrigeration system were discussed. Selected designs of multi-bed systems were analyzed. A verified prototype of our own soln. of a threebed adsorption refrigeration system was presented. Examples of results from the verification of the system for which the temp. in the evaporator was reached at the level of approx. 6°C were presented. An innovative element of the system was the shape of the prototype stainless steel adsorbers, which were made in 2 different design solns.: cylindrical-cross and cylindrical-tube. Due to their operational parameters, the presented adsorption systems can be used for the management of low-temp. waste heat in industry.
EN
Industrial activities in coastal areas can produce pollutant substances that are detrimental to the ecological environment. This study aimed to assess the ecological risks of heavy metal pollution in water, sediments, and polychaeta (Neoleanira tetragona) affected by aquaculture, urban rivers, and ports. Water parameters such as temperature, DO, pH, and salinity were measured in situ at fifteen observation stations. Samples were taken at three locations around the aquaculture area, namely the Barong River, the Musi River Estuary as an urban river area, and Tanjung Api-api port in South Sumatra, Indonesia. Analysis of sediment grain size and substrate types using the method of Shepard’s triangle Heavy metal concentrations were measured by graphite furnace atomic absorption spectrometry. Then, the data were analyzed using one-way analysis of variance (ANOVA) and post-hoc Tukey statistical analysis. Ecological risk assessment uses the bioconcentration factor (BCF), index geoaccumulation (Igeo), contamination factor (Cf), and pollution load index (PLI). Based on the results, the concentration of heavy metal Pb in water was not detected until 0.625 mg/L, and Cu was not detected. Furthermore, Pb in sediments was 1.261–11.070 mg/kg, Cu was 0.193–19.300 mg/kg, Pb polychaeta was not detected until 0.0044 mg/kg, and Cu ranged from 0.0003–0.0014 mg/kg. Ecological risk assessment for BCF showed that the level of accumulation of polychaeta (N. tetragona) was categorized as an excluder (BCF < 1). Igeo and Cf indicate uncontaminated pollution levels (Igeo < 0) and low contamination (Cf < 1). Meanwhile, the Pollution Load Index is included in the nonpolluted category (PLI <0). Based on the results, the quality of the ecological environment affected by aquaculture, urban rivers, and ports is still classified as safe for ecological risk assessment; further studies are needed regarding the relationship between pollution levels and the physiological response of biota.
PL
Woda, jak powszechnie wiadomo, jest źródłem życia. Jej dostępność szczególnie ważna jest na terenach zurbanizowanych, gdzie drzewa – zwłaszcza te nowo posadzone – bardzo często cierpią z powodu jej braku. Niewystarczająca ilość wody w pierwszych latach po posadzeniu drzewa skutkuje jego osłabionym wzrostem, a nawet zamieraniem. Fakt ten sprawia, że prawidłowe utrzymanie się młodych drzew w trudnych warunkach siedliskowych uzależnione jest głównie od prawidłowej ich pielęgnacji. Jednak wiele drzew mimo sumiennego podlewania wciąż rośnie źle lub zamiera. Gdzie szukać przyczyny?
PL
Martwe drewno – na przekór swej nazwie – pełne jest życia. Trudno dziś wyobrazić sobie zajęcia z ekologii, podczas których nie mówiłoby się o tym, jak jest ważne. I choć świadomość w tym zakresie rośnie, to wciąż myśli się o nim głównie w kontekście lasów o charakterze naturalnym. Tymczasem wielkogabarytowe martwe drewno w przestrzeni miejskiej to nie tylko siedlisko zastępcze dla niezliczonej rzeszy drobnych bezkręgowców, grzybów i mikroorganizmów, ale także magazyn wody, stanowiący wręcz alternatywę dla ogrodów deszczowych.
PL
W wielu polskich miastach jeziora i stawy (naturalne bądź sztuczne) od wielu lat podnoszą jakość krajobrazu aglomeracji, służą celom rekreacyjnym oraz stanowią siedlisko życia licznych gatunków flory i fauny. Stają się bardzo cenne zarówno przyrodniczo, jak i społecznie ze względu na stale zmieniające się warunki klimatyczne i brak stabilności pogodowej.
PL
Dyskusja o wodzie w przestrzeni naszego życia nie milknie. I milknąć nie może, skoro żyjemy w okresie przewlekłej suszy. W społeczeństwie slogan „woda to życie” ma wydźwięk starej prawdy – przecież wszyscy to wiemy. Jednak w nauce zdanie to staje się gorącym tematem, w szczególności w momencie gorącego lata.
EN
Purpose: Smart water meters (Internet of Things based) are technologically advanced tools delivering precise data on water consumption in a household. However, it has not been examined yet what influences consumer intention to adopt smart water meters. The study objective is to investigate predictors of consumer intention to install smart water meters. The Technology Acceptance Model was applied as the main theoretical framework. Design/methodology/approach: Data were collected from 366 respondents through an online survey conducted in 2021. Structural equation modeling was used for hypotheses verification. Findings: The intention to adopt smart water meters was mainly predicted by attitude towards the use of smart water meters. which, in turn, was predicted both by perceived ease of use and by perceived usefulness of these devices. The direct positive impact of perceived ease of use on the intention to adopt smart water meters was also found, whereas the direct relation between perceived usefulness of smart water meters and the intention for the adoption turned out to be statistically insignificant. Research limitations/implications: One research limitation is the probable lack of smart water meter usage among the responders, which may have affected their perception on how these devices are useful and easy to use. Additionally, only the main variables of TAM were applied, thus, other variables were not considered that may have had impact on perceived usefulness and perceived ease of use or usage behavior. Social implications: Considering practical implications, by analyzing what may influence consumers to adopt smart water meters, we are able to apply this knowledge in real life and increase the amount of smart water meters in households, which may lead to household water reduction. Originality/value: In previous research. what influences consumers to apply smart water meters has not been examined. This research indicates variables (adopted by TAM) influencing consumers to apply smart water meters, potentially leading to reduction in household water consumption.
EN
Performance modelling and assessment of Water Supply System (WSS) is a critical activity in system management process. It contributes into producing indicators necessary for the optimisation of the system operation, maintenance, safety, and resources use. The Water Supply Network (WSN) is a major component of any WSS. Assessing the performance of the WSN requires the development of dynamic-probabilistic models and the use of performance notions that are beyond the local availability and reliability of a cluster of pipes (mains, connections, and distributions) or nodes. The proposed performance notions are fully described in terms of performance-levels. The proposed modelling scheme is applied on a real WSN that has slightly been modified to preserve the didactic quality of the chapter and render the modelling scheme accessible at its first uses. Once the use of the scheme is mastered, its exploitation for real and complex WSN is straight forward.
9
Content available Analysis of tariff adjustment for clean water usage
EN
This study aims to assess the water supply company’s tariff modification under various circumstances. To evaluate the financial situation if no tariff modifications were made, the study first conducted an examination of the existing financial data. A tariff adjustment scenario is also run through an investment feasibility test and until it reaches the full cost recovery (FCR). A variety of scenarios for tariff adjustment were run, each one with a different percentage increase in tariffs and a different time period for the increase in tariffs. These scenarios were based on the findings of the analysis done on the water demand and the adjustment of water usage tariffs at PDAM Tirta Musi Palembang. This hypothetical situation demonstrated how higher tariffs will affect the company’s ability to increase revenue. To sum up, this study has offered a framework about tariff adjustment under various alternatives, and examples of successful and unsuccessful pricing strategies in the local water company.
10
Content available remote Woda a energetyka w obliczu wyzwań i realizacji celów zrównoważonego rozwoju
PL
Świadomość, że woda pokrywa 72% powierzchni globu, powoduje, że traktujemy ją jako dobro nieograniczone i ogólnodostępne. Wzrost populacji ludzi związany jest z potrzebami w zakresie wytwarzania żywności oraz energii, a do tego woda jest niezbędna. Woda wykorzystywana jest w gospodarstwach domowych w rolnictwie, w transporcie wodnym, w produkcji energii elektrycznej i we wszystkich gałęziach przemysłu. Potrzeby poszczególnych sektorów gospodarki, w zakresie wykorzystania zasobów wodnych, mogą się różnić, a nawet być przeciwstawne. Dlatego rola właściwego zarządzania zasobami wodnymi jest bardzo istotna. Powinna uwzględniać zarówno potrzeby ludności i gospodarki, jak i wymagania ochrony wód i ekosystemów z nimi związanych oraz kwestie dotyczące ochrony przed powodzią i suszą.
EN
Knowing that the water covers 72% of the globe's surface makes us treat it as an unlimited and universal good. The growth of the human population is related to the needs for food and energy production, and water is essential for this. Water is used in households in agriculture, in water transport, in electricity production and in all industries. The needs of individual economic sectors in terms of the use of water resources may differ and even be contradictory. Therefore, the role of proper management of water resources is very important. It should take into account both the needs of the population and the economy, as well as the requirements for the protection of water and related ecosystems, as well as issues related to protection against floods and drought, and each of us can take action to save the water.
EN
The main product of the conversion of ethanol to acetone on a ZnO-CaO catalyst is acetone, the yield of which strongly depends on the composition of the reaction environment. When oxygen is present, the yield of products of destructive and complete oxidation increases greatly. In contrast, when water vapor is present, both the selectivity and conversion of ethanol increase. Therefore, the conversion of ethanol is the limiting step in the overall process, which determines the selectivity of the conversion of ethanol to acetone. In this regard, it appeared suitable to investigate the effect of introducing water to the contact zone. As experiments indicated, the addition of water caused a significant effect on the conversion, selectivity, and acetone yield on the ZnO-CaO catalyst. As the partial pressure of water vapor increases, the conversion of ethanol and the acetone yield increase, while the yield of carbon dioxide decreases. The decrease in carbon dioxide is associated not only with the inhibition of the conversion of ethanol to CO2. In this study, the adsorption of water vapor and ammonia on the surface of the ZnO-CaO catalyst was examined by infrared spectroscopy method. It has been shown that water vapor at low temperatures is adsorbed on the catalyst surface in the molecular form, while at higher temperatures it is adsorbed in the dissociative form. Co-transformation reactions of ethanol with acetic acid, acetaldehyde with ethylene, and acetaldehyde with acetic acid have been studied. The obtained results indicated that acetone is formed mainly through the stage of complexation of acetaldehyde with ethylene. The isomerization reaction of 1-butene to 2-butene has been investigated. It was found that the yield of cis-2-butene in the absence of water vapor is higher, likely attributed to the molecular adsorption of water on Lewis centers. Based on these findings, a scheme for the vapor-phase conversion of ethanol into acetone on the studied catalysts was formulated.
PL
Głównym produktem konwersji etanolu do acetonu na katalizatorze ZnO-CaO jest aceton, którego wydajność silnie zależy od składu środowiska reakcji. W obecności tlenu znacznie wzrasta wydajność produktów destrukcyjnego i całkowitego utlenienia. Natomiast w obecności pary wodnej wzrasta selektywność i konwersja etanolu. Dlatego konwersja etanolu jest etapem ograniczającym w całym procesie, który określa selektywność konwersji etanolu do acetonu. W związku z tym celowe wydawało się zbadanie wpływu domieszek wody do strefy kontaktu. Jak wykazały doświadczenia, dodatek wody miał istotny wpływ na konwersję, selektywność i wydajność acetonu na katalizatorze ZnO-CaO. Wraz ze wzrostem ciśnienia cząstkowego pary wodnej wzrasta konwersja etanolu i wydajność acetonu, podczas gdy wydajność dwutlenku węgla maleje. Spadek dwutlenku węgla jest związany nie tylko z hamowaniem konwersji etanolu do CO2. W niniejszej pracy metodą spektroskopii w podczerwieni badano adsorpcję pary wodnej i amoniaku na powierzchni katalizatora ZnO-CaO. Wykazano, że para wodna w niskich temperaturach jest adsorbowana na powierzchni katalizatora w postaci cząsteczkowej, natomiast w wyższych temperaturach jest adsorbowana w postaci dysocjacyjnej. Zbadano reakcje kotransformacji etanolu z kwasem octowym, aldehydu octowego z etylenem i aldehydu octowego z kwasem octowym. Uzyskane wyniki wykazały, że aceton powstaje głównie na etapie kompleksowania aldehydu octowego z etylenem. Zbadano reakcję izomeryzacji 1-butenu do 2-butenu. Stwierdzono, że wydajność cis-2-butenu w nieobecności pary wodnej jest większa, co prawdopodobnie wynika z molekularnej adsorpcji wody na centrach Lewisa. Na podstawie uzyskanych wyników zaproponowano schemat przemiany etanolu do acetonu w fazie gazowej na badanych katalizatorach.
EN
In the geological structures containing crude oil and associated gases and located in areas where volcanic activity has been detected, radioactive substances and minerals are contained both in the structure of the reservoir waters and in the impurities related to the composition of the extracted crude oil. They are present during the extraction of crude oil and associated gases and affect human health and environmental safety. Radioactive elements have been detected in reservoir waters, in impurities associated with crude oil, and especially during the processing of drilling fluids (the separation of detritus sourced from geological strata from the used drilling fluid). Other radioactive elements were also detected in the areas polluted with oil and drilling waste. In order to determine the radioactivity level of crude oil originating from the area of volcanic activity of the Romanian Mountains, crude oil samples were collected from the oil field in a one-year analysis. The collected samples were analysed to determine their physical-chemical structure. The reservoir water associated with these samples and the minerals separated from the crude oil following their solvent extraction were also analysed. Radioactive elements were detected using X-ray spectrometry, and their chemical structures are also discussed.
PL
W strukturach geologicznych zawierających ropę naftową i towarzyszący jej gaz ziemny oraz zlokalizowanych w obszarach, w których wykryto aktywność wulkaniczną, substancje i minerały radioaktywne zawarte są zarówno w strukturze wód złożowych, jak również w zanieczyszczeniach powiązanych ze składem wydobywanej ropy. Są one obecne podczas wydobycia ropy naftowej i towarzyszącego jej gazu, mając wpływ na zdrowie ludzkie i bezpieczeństwo środowiska. Pierwiastki radioaktywne wykryto nie tylko w wodach złożowych i związanych z nią zanieczyszczeniach, ale przede wszystkim podczas obróbki płuczek wiertniczych, w tym w procesie oddzielania detrytusu pochodzącego z warstw skalnych od zużytej płuczki wiertniczej. Inne pierwiastki radioaktywne wykryto także w obszarach zanieczyszczonych ropą i odpadami wiertniczymi. Dla określenia poziomu radioaktywności ropy naftowej pochodzącej z obszaru aktywności wulkanicznej w górach Rumunii, z jednego ze złóż ropnych w ciągu jednego roku pobrano próbki ropy naftowej do analiz. Pobrane próbki przeanalizowano pod kątem struktury fizykochemicznej. Przebadano także wodę złożową powiązaną z tymi próbkami oraz minerały oddzielone z ropy naftowej po ich ekstrakcji rozpuszczalnikiem. Pierwiastki radioaktywne zidentyfikowano za pomocą spektrometrii rentgenowskiej, omówiono również ich struktury chemiczne.
14
Content available remote Specyfika dachów
EN
Flame retardants (FRs) that have an adverse effect on human and the environment have been subject to regulation since 1972. However, FRs emerging as a replacement, are not proving to be fully environmentally safe. Water and sediment contamination by FRs, including organophosphorus (OPFRs) and novel brominated (NBFRs) ones, is a matter of major concern. Due to their common usage, many release sources, and relatively high mobility, they pose a threat to aquatic organisms and ecosystems. This review summarises studies on the OPFRs’, and NBFRs’ simultaneous occurrence in water and corresponding sediment. The main sources of occurrence and routes of entry of FRs into the environment are presented. The newest reports on the ecotoxicity of selected FRs had been summarised in order to bring the matter to attention. The research revealed that although great efforts had been made to study the occurrence of OPFRs and NBFRs in water and sediment separately, there is a lack of research on their occurrence in both media in the same area. Although major efforts have been made to study the ecotoxicity of OPFRs, there are some deficiencies for the NBFRs. Considering their relatively high ecotoxicity, further studies should be conducted on joint ecotoxicity, which may cause synergistic or antagonistic effects.
EN
In recent years, many researchers have expressed interest in wastewater treatment using activated carbon produced from cheap raw materials. In this work, an activated carbo-aluminosilicate (ACS) – supported zero-valent iron (ZVI) composite was produced from Um AL-Rasa oil shale mine and examined to eliminate Chromium (VI) from contaminated water. Activation of raw oil shale fine particles (< 212 μm) was chemically performed using 95 and 5% wt of H2SO4 and HNO3, respectively, as activating agents. The activated material was further treated with caustic soda, named ACS, and modified with fine zero-valent iron particles < 212 μm), called ZVI/ACS composite. Kaolin was added to the composite with the ratio: (50 % wt. light kaolin: 50 % wt. ACS), named as ZVI/ACS/K. The XRD analysis for both composites confirmed iron dispersion at 45°. Adsorption experiments were carried out using the two adsorbents ZVI/ACS & ZVI/ACS/K under different values of pH, and adsorbent dosage. The results indicated that the reduction of Chromium was maximum under the 3 pH value and 2.0 gm amount of ZVI/ACS/K. Furthermore, it was found the removal rate was enhanced by 17% and 24.7% when ZVI/ACS & ZVI/ACS/K adsorbents were used, respectively, compared to that when only ACS adsorbent was used alone. Finally, the dependency of Chromium removal on its initial concentration by ZVI/ACS/K adsorbent was also investigated at two different temperatures of 27° and 50°. The results indicated a decrease in the removal rate of the Chromium as the concentration increased at 27°; however, the removal rate previously enhanced at 50° at all initial concentrations.
EN
At present, the problem of the availability of high-quality fresh water is urgent. The reservoirs from which water is extracted are running low. The amount of fresh water on the planet has decreased significantly in recent years. A big problem for the use of fresh water is its pollution. Groundwater remained relatively clean, but even when used, it needs to be controlled. Goal of research was the quality control of water from ponds and water sources in the National Dendrological Park (NDP) "Sofiyivka" of the National Academy of Sciences (NAS) of Ukraine in terms of physicochemical and bacteriological indicators and a study of the park's hydrosystem. When conducting research, potentiometric, gravimetric, titrimetric, colorimetric and spectrophotometric methods were used. The hydrosystem of the NDP "Sofiyivka" of the NAS of Ukraine, created during the period of its foundation, has basically retained its planning forms and all its artificial structures. The water system is an important environmental factor that contributes to the quality development of plants, and also has an aesthetic value. The analysis of the results of a study of the physicochemical and bacteriological composition of drinking water from the studied water catchments showed that the water is safe for consumption in terms of such indicators as the content of sulfates, nitrites, chlorides, but contains a significant amount of nitrates and has a high hardness, which can contribute to the development of a number of diseases. Long-term consumption of such water will have a negative impact on the human body. In all water samples from the capture, the growth of common coliforms in 100 cm3 and the presence of Escherichia coli were found, which is dangerous when drinking unboiled water and can bring to intestinal infectious diseases. According to the obtained experimental results of the quality of the studied water samples from the Krasnostavsky, Upper and Lower ponds of the NDP "Sofiyivka" NAS of Ukraine, the general physical and chemical indicators fully comply with the established standards, but the results of studies of the ponds in terms of bacteriological indicators, namely the index of lactose-positive E. coli indicate their significant excess and non-compliance with the standards in the Krasnostavsky and Verkhny ponds by 48 and 12 times, respectively.
EN
Microplastics are emerging contaminants that degrade from textile plastic products, petroleum, and cosmetic equipment with sizes less than 5 mm. There are more than 70,000 settlements located along the Ciliwung River in DKI Jakarta that use the river water as a source of clean water. The most common type of waste found in the Ciliwung River to date is plastic waste, which can cause flooding and other disasters. The Ciliwung River can currently be found with microplastic pollution which has an impact on exposure to living things in the river, such as in case studies in the Ciliwung River estuary area. The problem is the exposure to 75% of blue panchax fish (Aplocheilus sp.) as many as 1.97 particles per fish with sizes of 300 to 500 μm. This research will focus on analyzing the dynamics of microplastic quantity in water and sediment of the Ciliwung River along with the correlation between field parameters and population density around the banks of the Ciliwung River. When viewed from the seven points that represent the Ciliwung River downstream to upstream in DKI Jakarta Province, the number of microplastics is in the range of 320–741 particles/L. For the dominating form, it can be analyzed that the majority of microplastic forms are fragments (97%), followed by fibers (2.9%) and pellets (0.1%). While in the sediment, the number of microplastics in the Ciliwung River sediment is in the range of 6560–10630 particles/kg. The population density factor has the highest correlation to the number of microplastics with a value of r = 0.702. This is associated between population density and high microplastic emission loads.
EN
Generally, pesticides are the products containing at least one chemical substance which should protect plant or plant products against pests/diseases. Among them, the most important ones are herbicides, followed by insecticides and fungicides. As a result of intensive agriculture techniques, large amounts of pesticides are applied on agricultural soil. They remain and degrade in soil, but they can enter water bodies and negatively affect water quality and the aquatic ecosystem. The article deals with the level of pesticide load in soil, bottom sediment and surface water in chosen agriculture catchments in the Czech Republic. Results revealed that the main general problem is glyphosate and its metabolite AMPA, although their application has been constrained for several years. Furthermore, the difference in contents of chosen parent pesticide substances and their metabolites in soils and waters were pointed out.
EN
The accident at the Chornobyl nuclear power plant was one of the most serious nuclear incidents in human history. A radioactive plume covered a whole strip of northeastern Europe. The consequences of this catastrophe are still being felt, both in Ukraine and around the world. The article is devoted to the assessment of the consequences of radiocesium contamination of agricultural lands and irrigated waters during a possible accident at the Zaporizhzhia NPP and the associated Cs137 contamination of sunflower products in the Zaporizhzhia region. The studies were carried out using a dynamic mathematical model for the formation of radionuclide activity in the "water-soil-plant-product" system, ECOSIS-87 (Ecoplant). The article presents the results of studies of possible contamination of the environment by radiocesium according the Chornobyl NPP-86 scenario and sunflower production by the method of mathematical dynamic modeling. The calculations were carried out on the basis of the results of an agrochemical and agroecological survey of the state of soils in Ukraine and the Dnipro cascade of reservoirs. If an explosion occurs at the Zaporizhzhia NPP, the power of which will be equal to the Chornobyl NPP, then 100,000 hectares of agricultural land in the region will be taken out of the agricultural production of the Zaporizhzhia region. On agricultural lands where soil contamination with radiocaesium will be more than 5 Ci/km2, and the concentration in irrigated waters will reach 2 Bq/dm3, sunflower, which was grown for seeds to produce oil will need to be replaced with an industrial crop, which will also lead to loss of seed yield sunflower. Crop losses will lead to a decrease in the volume of sunflower oil. It should also be taken into account that the purification of soil and water does not occur in one year. At least in 5 years the situation will begin to improve.
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