Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 39

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  temperature change
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
1
100%
Subject of the study are changes of the water temperature occurring on the Polish Baltic coast during years 1951-2010 (in Kołobrzeg, due to deficiencies in the data, for the years 1957-2010). It is expressed in the form of a linear trend. The study was based on the monthly average temperature of the sea water in the following stations: Świnoujście, Międzyzdroje, Kołobrzeg, Władysławowo, Hel and Gdynia. For most of analyzed stations an increase in average annual temperature of the water were observed. The largest one was recorded in Gdynia. In Świnoujście there were no significant changes in water temperature except for the slight its drop in June. A significant increase in the water temperature occurred in Międzyzdroje in February, March, April and May; in Kołobrzeg in January and March; in Władysławowo in January, February, March, April and June and in Hel and Gdynia in February, March, April, May, July and August. The greatest changes were in April in Hel and Gdynia.
The impact of climate change on annual air temperature has received a great deal of attention from climatologists worldwide. Many studies have been conducted to illustrate that changes in temperature are becoming evident on a global scale. Air temperature, one of the most important components of climate parameters, has been widely measured as a starting point towards the apprehension of climate change and variability. The main objective of this study is to analyse the temporal variability of mean monthly temperature for the period of 1941 to 2010 (70 years). To detect the magnitude of trend in mean monthly temperature time series, we have used non-parametric test methods such as The Mann-Kendall test, often combined with the Theil-Sen’s robust estimate of linear trend. Whatever test is used, the user should understand the underlying assumptions of both the technique used to generate the estimates of a trend and the statistical methods used for testing. The results of this analysis reveal that four months – January, February, March and December – indicate a decreasing trend in average temperature, while the remaining eight months have an increasing trend. The magnitude of Mann-Kendall trend statistic Zc for this declining temperature and the magnitude of slope for the months of January, February and December are confirmed at the high significance levels of α = 0.001, 0.01 and 0.1 respectively. Though, the overall trend is positive for monthly as well as seasonally efficient time series.
The article analyses the air temperature characteristics of the winter season in Koszalin from 1850 to 2010. The trends of changes have been determined. In addition, the frequency of thermal anomalies has been shown. The thermal classification of Lorenc has been adopted for this study. The relationship between the North Atlantic Oscillation and the air temperature in winter seasons has been estimated.
The knowledge about the awakening of hibernating bats is not sufficient. Unknown are also factors affecting the cyclical nature of this process. The aim of the study was to determine the impact of changes of phases of the moon, and thus changes in the Earth's magnetic field on the behaviour of wintering common noctules Nyctalus noctula Schreber. Hibernation of 336 common noctules placed in the hibernation shed was investigated. The shed was equipped with loggers which measured temperature. Based on the temperature changes inside the shed, a drop or an increase in bat activity was determined. Periodicity of temperature increase was observed and it correlated with the current moon phases. The moon phase regarded as the bright referred to more than 70% of moon face illuminated (MFI). The significant temperature increase inside the shed was observed at 70% MFI. This is also when the bats demonstrated an increased activity. The observed differences in the temperature inside the shed during bright nights were statistically significant. The results of the research indicate that moon phases have influence on awakenings coordination in the wintering colony of noctule bat. This phenomenon causes difficulties in interpretation. If bats are in fact able to distinguish moon phases the moon appears to be the perfect tool to control their internal biological clock.
The aim of this study was to determine changes in temperature found during short-term seedling storage on shelves kept on racks under different cover materials. Analyses assessed the effect of different materials for covering of loading space on interior temperature changes. Collected results were to supply information on the effect of this factor on the quality of seedling material in view of specific conditions produced under the cover. Analyses were conducted under conditions found in the loading space using temperature and humidity sensors by Vaisala. The distribution of sensors at different levels in the loading space and the fact that some of them were coupled with fans enforcing air circulation made temperature measurements possible over a larger space. Results were recorded using a KNE Data Logger, recording the results on the PCMCIA memory card. The device recorded data collected from the measurements taken over any selected period. This facilitated analysis of the effect of a direct impact of external conditions on temperature changes in containers under covering made of different materials. It results from the conducted investigations that air temperature in each measurement site fluctuated. During intensive solar radiation a marked increase in temperature was observed under container covering. It was found that the covering material for the racks has a very big effect on the course of changes in temperature inside the racks.
The increase of Lyme borreliosis (LB) can be expected due to climate change, while the distribution of the disease and annual activity of the vector and host animals depend on several factors of the environment. The presented study aimed to assess expressly the spring season temperature dependence on the incidence of LB in Hungary. The weekly LB data were obtained from the National Epidemiologic and Surveillance System for a period of 13 years – 1998–2010. Daily temperature data were derived from the European Climate Assessment and Dataset. The association was studied at national level, descriptive statistics and linear regression models were applied. A significant increasing trend was observed in the mean temperature of the analysed years (0.052 °C per year). The annual LB incidence doubled during the 13 year period. The incidence rates of the periods 1998–2001 and 2007–2010 were 11.1 resp. 17.0 per 100,000. The start of a steep increase in weekly LB incidence (0.1 per 100,000) shifted significantly by 3 weeks earlier, the start date of spring showed similar trend (p=0.0041). LB incidence increased more steadily in spring than in summer, with 79% of the increase being reported during weeks 15–28, with maximum rates of increase occurring in weeks 23–25. The trend was significant between the weeks 15–28. In the warmer years with 19.02 °C mean temperature in May and June, the LB incidence curve reached the annual peak 2–3 weeks earlier, and the descending phase of the curve started earlier than in the colder years with 17.06 °C of the same period.
Wyznaczono daty początku i końca oraz liczbę dni okresu wegetacyjnego (1971-2005). Ponadto analizie poddano średnie miesięczne wartości temperatury powietrza po-szczególnych miesięcy okresu wegetacyjnego. Kierunek oraz istotność tendencji zmian określono na podstawie równań trendu liniowego. Termiczny okres wegetacyjny w środkowo-wschodniej Polsce rozpoczynał się około 28 III i trwał do 30 X. Południowo-zachodnia część badanego obszaru charakteryzowała się najwyższą średnią temperaturą powietrza okresu wegetacyjnego (IV-X), a północno-wschodnia najniższą. W większości analizowanych stacji w kwietniu, lipcu i sierpniu zanotowano dodatnie istotne statystycznie zmiany temperatury powietrza. Najwyższy wzrost tego parametru (średnio o 0,7oC na 10 lat) zanotowano w kwietniu. W stacjach położonych we wschod-niej części badanego regionu istotny (średnio o 0,4oC na 10 lat) wzrost temperatury wystąpił rów-nież w październiku.
The aim of this work was to examine the influence of drying parameters on temperature changes during vacuum drying of defrosted and osmotically dehydrated strawberries. This work presents curves of temperature above fruits, temperature of fruits’ surfaces and internal temperature of strawberries’ flesh during 8 h of drying. The increase of the setting temperature of drying from 40 to 60°C was observed to affect the samples’ surface and the internal temperature (to a greater extent in the case of defrosted strawberries than osmotically dehydrated strawberries) and the temperature above fruits (to the same degree in the case of defrosted strawberries and osmotically dehydrated strawberries). Furthermore, the pressure decrease from 20 to 4 kPa had an influence on the declining samples’ surface and internal temperature as well as on the temperature above fruits (to a greater extent in the case of defrosted strawberries than in the case of osmotically dehydrated strawberries). During vacuum drying, the temperatures of fruits’ surface or tissue and above fruits were lower in the case of defrosted strawberries than in the case of osmotically dehydrated strawberries.
The article is devoted to temperature changes in the ground massif with the horizontal heat exchanger as an energy source for a heat pump. The article was aimed at analyzing temperature changes in the ground massif with the horizontal heat exchanger at the beginning, in the course of and at the end of the heating season. Another aim was to analyze temperature differences in the area of the horizontal exchanger and the reference lot. The heat flow utilized in the evaporator of heat pump was extracted from the ground exchanger (nominal output at the condenser was 10.5 kW). Temperatures of the ground massif with the horizontal heat exchanger were measured in its plane in depths of 0.75 m, 0.5 m and 0.25 m. The temperature inside the ground massif on the reference lot and ambient parameters were measured as well. It is obvious that the difference of energetic potentials inside the ground massif with the heat exchanger and on the reference lot is insignificant at the beginning of the heating season. During the heating season, the difference of ground massif energetic potentials increases; at the end it is constant. The difference of temperatures in horizontal planes was not significant at the beginning of the heating season; however, it gradually increased. Maximum differences were detected in the area of the heat exchanger. In higher strata, the difference between temperatures decreases. During a major part of the heating season, temperatures at pipes of the ground exchanger were negative. This fact affected amounts of heat extracted from the ground massif.
W pracy przedstawiono wyniki badań nad próżniowym schładzaniem pieczarek. Schładzano je w komorze próżniowej podłączonej do pompy próżniowej. Podczas schładzania mierzone były następujące parametry: temperatura w komorze, temperatura na powierzchni pieczarki, temperatura w centrum pieczarki, zmiany masy pieczarek oraz ciśnienie w komorze. Na podstawie uzyskanych wyników przedstawiono kinetykę zmian temperatury w centrum i na powierzchni pieczarek podczas badanego procesu. Przeanalizowano zmiany masy schładzanych pieczarek i zmiany ciśnienia w komorze próżniowej. Przedstawiono tabelaryczną zależność ubytku masy od temperatury schładzanych grzybów. Najwyższa szybkość obniżania temperatury wystąpiła w początkowym fazie schładzania i wyniosła 2,7 deg·min-1. W końcowym okresie szybkość schładzania zmalała do 0,75 deg·min-1. Podobnie jak w przypadku zmian temperatury szybkość zmian masy malała wraz z czasem trwania procesu schładzania. Na początku wynosiła 1,8 g·min-1, a w końcowym okresie zmalała do 1,2 g·min-1. Średnia szybkość ubytku masy podczas całego procesu wyniosła 1,4 g·min-1.
The aim of the study was to investigate changes of internal temperature and locomotor activity of birds in conditions of endotoxin fever, pyrogenic tolerance and its suppression. The experiment was performed in pigeons (n = 12). On the first day of the experiment a state of endotoxin fever was evoked. The pigeons were categorized into two groups: experimental and control. The first group of the animals (n = 8) received Escherichia coli LPS intravenously once at the dose of 10 µg/kg b.w. whereas the control pigeons (n = 4) were administered in the apyrogenic saline intravenously once at the dose of 1 ml/kg b.w. On the second and third day of the experiment the state of pyrogenic tolerance was induced in the pigeons and their internal temperature and locomotor activity were investigated. To this end the experimental group of birds received E. coli LPS intravenously twice at 24 h intervals at a dose of 10 µg/kg b.w. Conversely, the control pigeons were twice treated with saline (1 ml/kg b.w.). On the fourth day of the study an attempt of pyrogenic tolerance suppression in the pigeons was carried out. The experimental birds with the stable state of pyrogenic tolerance were then categorized into two subgroups. The first subgroup (n = 4) received Salmonella Abortusequi LPS intravenously at the dose of 10 µg/kg b.w., whereas the second one (n = 4) - E. coli LPS at a double amount of the pyrogen (20 µg/kg b.w.). The control pigeons were administered S. Abortusequi LPS in an analogical dose as the first experimental subgroup. Results of the study indicated the occurrence of endotoxin fever and depression of locomotor activity of the pigeons in response to the first injection of E. coli LPS. The third administration of the pyrogen stabilized the state of pyrogenic tolerance, manifested by the reduction of the increased internal temperature and the stimulation of pigeon locomotor activity. Whereas in the state of stable pyrogenic tolerance in pigeons the intravenous injection of the other exogenous pyrogen, i.e. S. Abortusequi LPS, and also the double dose of E. coli pyrogen caused the suppression of the tolerance and the restoration of endotoxin fever in the birds.
The effect of air temperature on variability of phenophase dates and the length of spring triticale interphases was investigated by means of simple linear regression analysis. An increase in the mean temperature in Poland observed in 1965-2004, the biggest for the mean temperature in August (+0.53°C/10 years, P<0.01) and April (+0.50°C/10 years, P<0.01), caused significant, with P<0.01, acceleration of phenophase dates. The bigger the size of changes, the later the phenophase it concerned – for beginning of tillering the average acceleration of the date amounted to +1.8 day/10 years, for beginning of shooting +3,4 day/10 years, for beginning of heading +4.2 days /10 years, and for wax maturity as many as +10.2 days /10 years. The duration of periods of emergencetillering and tillering-shooting in 1984-2004 became shortened by, respectively, -1.0 day/10 years and –1.5 day/10 years, and the period of heading-wax maturity by –5.9 day/10 years. On the basis of the generalized method of cluster analysis it was determined that the biggest yields of spring triticale crops can be obtained with earlier than average dates from sowing to beginning of heading, and close to average dates of wax maturity and harvesting, and also longer than average interphases: sowing-emergence, emergence-tillering, shooting-heading and periods: sowing-wax maturity and sowing-harvesting, and with close to average duration of periods: heading-wax maturity and wax maturity-harvesting.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.