The Fountains of Łódź: Their Relevance to the Lives of its Inhabitants

This paper presents the characteristics of the fountains of Łódź, their location in the public spaces of the city and changes in various time periods. Special attention is drawn to the function of fountains in contemporary cities and their social perception. Moreover, in the last part, the presumed reasons for their present distribution and typological variety are given

Maximum discharges and maximum runoffs in Poland

Published in: Natural environment of Poland and its protection in Łódź University Geographical Research, edited by E. Kobojek and T.Marsza

Spatial variability of precipitation in the area of Lodz

Opracowanie jest próbą ustalenia przestrzennej zmienności opadów atmosferycznych na obszarze Łodzi, w jej granicach administracyjnych, a równocześnie częścią większego projektu zmierzającego do opracowania zintegrowanego modelu odpływu rzecznego w warunkach silnej antropopresji. Do realizacji tego zadania, posłużono się danymi zarejestrowanymi w latach 2010–2012 przez różne instytucje działające w obrębie aglomeracji (rys. 1). Pozyskane szeregi cechowała jednak nieciągłość oraz istnienie błędów o różnej genezie i o różnym charakterze. Dlatego pierwszym zadaniem było wykrycie i uzupełnienie braków pomiarów lub ich poprawienie. Ostatecznym celem prezentowanego opracowania było uzyskanie sekwencji map obrazujących przestrzenne zróżnicowanie opadów w poszczególnych latach trzylecia 2010–2012 oraz ich średnich sum rocznych w tym okresie, co ma pozwolić na określenie przestrzennej zmienności dostawy wody do powierzchni terenu. Efektem była sekwencja map przedstawiających przestrzenne zróżnicowanie opadów atmosferycznych na obszarze miasta w poszczególnych latach okresu (rys. 3), średnich sum opadów (rys. 4), maksymalnych dobowych sum opadów (rys. 5), maksymalnych godzinowych sum opadów (rys. 6) oraz liczby dni z opadem >0,1 mm (rys. 7) w badanym okresie.This study is an attempt to determine the spatial variability of precipitation in the city of Lodz, within its administrative boundaries, and it’s a part of the larger project, which aims to develop an integrated river outflow model under a strong anthropopressure. Therefore, the hydrologic year was taken (from November 1 to October 31). To accomplish this task, the data recorded in 2010–2012 by various institutions operating within the agglomeration were used (fig. 1). Data strings from 24 rain gauges were used. However, the obtained sequences were characterized by discontinuity and the existence of various origin errors and different character. Therefore, the first task was to detect and fill the measurement gaps or to correct them. The ultimate aim of the present study was to obtain a cartographic representation of the spatial variability of precipitation in each year of the period 2010–2012 (fig. 3) and their average annual throughout this period (fig. 4), which made it possible to determine the spatial variability of water flow to the surface. Figs. 5 and 6 represent respectively the maximum daily rainfall and maximum hourly rainfall recorded in the investigated three-year period. Fig. 7 shows the average annual number of days with precipitation in the city area. Despite the very dense measurement network (which continues to be expanded) and a very high resolution of data, it was a difficult task, which required multi-step preparation and verification procedures. Data strings were incomplete or affected by errors of various kinds. One must therefore be aware of the imperfections of data collected automatically. Studies on spatial distribution of precipitation, their duration and intensity can be used to understand the causes and learn the scope of urban flooding. Creation of storm sewers control system which reacts in real-time to readings of automatic stations will avoid future losses related to sudden urban floods

Detection and clearing of trapped ions in the high current Cornell photoinjector

We have recently performed experiments to test the effectiveness of three ion-clearing strategies in the Cornell high intensity photoinjector: DC clearing electrodes, bunch gaps, and beam shaking. The photoinjector reaches a new regime of linac beam parameters where high CW beam currents lead to ion trapping. Therefore ion mitigation strategies must be evaluated for this machine and other similar future high current linacs. We have developed several techniques to directly measure the residual trapped ions. Our two primary indicators of successful clearing are the amount of ion current removed by a DC clearing electrode, and the absence of bremsstrahlung radiation generated by beam-ion interactions. Measurements were taken for an electron beam with an energy of 5 MeV and CW beam currents in the range of 1-20 mA. Several theoretical models have been developed to explain our data. Using them, we are able to estimate the clearing electrode voltage required for maximum ion clearing, the creation and clearing rates of the ions while employing bunch gaps, and the sinusoidal shaking frequency necessary for clearing via beam shaking. In all cases, we achieve a maximum ion clearing of at least 70 percent or higher, and in some cases our data is consistent with full ion clearing

The Dependence Of Lead-Salt Nanocrystal Properties On Morphology And Dielectric Environment

The IV-VI semiconductors, and specifically the lead-salts (PbS, PbSe, and PbTe), are a natural choice for nanocrystal science. In nanocrystals, because of their narrow band gap, small effective masses, and large dielectric constants, they offer a unique combination of both strong confinement and strong dielectric contrast with their environment. Studying how these two effects modify optical and electrical properties of nanocrystals will be the topic of this dissertation. We begin with a summary of the synthesis of high-quality PbS and PbSe nanocrystals. Special care is taken to explain the chemical procedures in detail to an audience not expected to have significant prior chemistry knowledge. The synthesized nanocrystals have bright and tunable emission that spans the edge of the visible to the near-IR spectrum (700-1800 nm), and they are capped with organic ligands making them easily adaptable to different substrates or hosts . This combination of high optical quality and flexible device engineering make them extremely desirable for application. Moving beyond single-material nanocrystals, we next explore nanocrystal heterostructures, specifically materials with a spherical core of one semiconductor and a shell of another. Core-shell structures are commonly used in nanocrystals as a method to separate the core material, where the electrons and holes are expected to stay, from interfering effects at the surface. This typically results in improvements in stability and fluorescence quantum efficiency. To that end, we develop a model to explain how confinement plays out across abrupt changes in material, focusing on the optical and electrical properties of recently synthesized PbSe/PbS core-shell quantum dots. We show that for typical sizes of these nanocrystals, a novel type of nanocrystal heterostructure is created, where electrons and holes extend uniformly across the abrupt material boundary, and the shell does not act as a protecting layer. For very large sizes not yet achievable, we expect that the electron and hole will separate in different layers, with potentially measurable effects. Comparisons are made to optical and electrical measurements on these structures, showing good agreement. Next, we explore how shape can impact nanocrystal properties, on top of their intrinsic size or material dependence. By looking at cylindrically shaped nanocrystals, called "nanorods," with aspect ratios 10, we explore how having a slightly extended dimension can impact nanocrystal properties. A model is developed to explain their electronic structure, with surprising results. Foremost is that along the extended dimension, electrons and holes are strongly electrically bound, not with each other directly, but with their image charges in the outer host dielectric material. Nevertheless, the energy spectra of the excitons remains nearly hostindependent, with the effects of this strong binding instead seen in a redistribution of transition oscillator strength. To test the model, we develop a novel synthesis of high quality PbSe nanorods, and find good agreement with measured absorption spectra. Finally, we present a study on the transfer of charge into and out of a nanocrystal. By modeling the charge transfer process within a modified Marcus Theory, we isolate the relevant parameters that can be used to control the rate of transfer. Primary among these are the values of the quantum dot energy levels, and the electrostatic charging energy of the acceptor. We vary the former by changing the quantum dot size, and the latter by varying the host dielectric constant. To test the model, we chemically bind a small molecular acceptor molecule to the surface of PbS nanocrystals and use transient fluorescence to measure the rate of charge transfer. Both the dependence of the rate on quantum dot size and host dielectric constant show good agreement with the model

Funkcjonowanie osadników i zbiorników przepływowych w warunkach zlewni miejskiej i podmiejskiej (Sokołówka i Dzierżązna)

The presence of small artificial water reservoirs is typical of the landscape of small agricultural catchments. The old mill dammings are used today mostly for recreation and fish farming. Moreover, they are a very important part of the hydrological system of small rivers, stabilizing and shaping the discharge and physico-chemical characteristics of water. Coupled with the landscape function of the ponds goes their functioning in conditions of strong human pressure in the urban space. A canalized rivers in the urban parts of its courses picks up rubbishes washed down from the surface and coming from a storm sewer system and sometimes from leachate from a sanitary sewage system.An example of hydrological systems operating in such environments are Dzierżązna and Sokołówka catchments (Fig. 1). The first one is located north of Zgierz in the impact zone of the city of Łódź. Despite agro-forestry character, a significant impact on water quality is the chalets area and the A2 motorway crossing the catchment. The Sokołówka catchment is flowing through the urban area of the Łódź city. Both of the river flows are highly variable, and the water is heavily contaminated and has a high load of suspension (Tab. 1)In both of the catchments the role of artificial reservoirs created to improve the quality of water is the important issue. In the Dzierżązna catchment the several retention and infiltration ponds are working for regulating the outflow from the A2 motorway. In the Sokołówka valley the biofilter has been recently built (Fig. 2). It was constructed in order to purify urban storm- and waste water (sequential biofiltration system of Sokołówka – SSBS). The main purpose of the constructed SSBS was to remove sediments, suspended solids, particulate pollutants, petroleum hydrocarbons, heavy metals, nutrients and bacterial contamination from storm-water runoff through sedimentation and filtration mechanisms.The paper discusses the construction of both systems and technical solutions. To evaluate the effectiveness of their operation analyzed changes in the basic characteristics of physicochemical water parameters (water temperature, conductivity (SEC), pH, the concentration of dissolved oxygen, turbidity (NTU)) measured before and after both of cleansing systems in the year and multiyear (Fig. 3, Fig. 4).Attention has been also paid to the distribution of the mineral sediment deposited on the bottom of the biofilter SSBS system (Fig. 5). It was found that lowering the temperature in the winter and the appearance of a compact ice cap adversely affect the ability of biofilm to absorb pollutants causing (relative to the hot half year) an increase of conductivity, a higher pH and reducing of oxygenation of water.Identified mean changes of the selected physicochemical parameters of water discharged from the area of the A2 motorway to the Dzierżązna river system and as a result of the SSBS system operation to Sokołówka river (Fig. 6).All the measured parameters are reduced after passing through both of systems. As a result of mechanical sedimentation the greatest reduction is suspended material transported by water – in the SSBS on average about 16% less than in untreated waters (in the Dzierżązna catchment this element was not measured). The pH of the water in both systems changes to the same extent – decreases by 10% in the Dzierżązna, and 7% in SSBS.The presence of small artificial water reservoirs is typical of the landscape of small agricultural catchments. The old mill dammings are used today mostly for recreation and fish farming. Moreover, they are a very important part of the hydrological system of small rivers, stabilizing and shaping the discharge and physico-chemical characteristics of water. Coupled with the landscape function of the ponds goes their functioning in conditions of strong human pressure in the urban space. A canalized rivers in the urban parts of its courses picks up rubbishes washed down from the surface and coming from a storm sewer system and sometimes from leachate from a sanitary sewage system.An example of hydrological systems operating in such environments are Dzierżązna and Sokołówka catchments (Fig. 1). The first one is located north of Zgierz in the impact zone of the city of Łódź. Despite agro-forestry character, a significant impact on water quality is the chalets area and the A2 motorway crossing the catchment. The Sokołówka catchment is flowing through the urban area of the Łódź city. Both of the river flows are highly variable, and the water is heavily contaminated and has a high load of suspension (Tab. 1)In both of the catchments the role of artificial reservoirs created to improve the quality of water is the important issue. In the Dzierżązna catchment the several retention and infiltration ponds are working for regulating the outflow from the A2 motorway. In the Sokołówka valley the biofilter has been recently built (Fig. 2). It was constructed in order to purify urban storm- and waste water (sequential biofiltration system of Sokołówka – SSBS). The main purpose of the constructed SSBS was to remove sediments, suspended solids, particulate pollutants, petroleum hydrocarbons, heavy metals, nutrients and bacterial contamination from storm-water runoff through sedimentation and filtration mechanisms.The paper discusses the construction of both systems and technical solutions. To evaluate the effectiveness of their operation analyzed changes in the basic characteristics of physicochemical water parameters (water temperature, conductivity (SEC), pH, the concentration of dissolved oxygen, turbidity (NTU)) measured before and after both of cleansing systems in the year and multiyear (Fig. 3, Fig. 4).Attention has been also paid to the distribution of the mineral sediment deposited on the bottom of the biofilter SSBS system (Fig. 5). It was found that lowering the temperature in the winter and the appearance of a compact ice cap adversely affect the ability of biofilm to absorb pollutants causing (relative to the hot half year) an increase of conductivity, a higher pH and reducing of oxygenation of water.Identified mean changes of the selected physicochemical parameters of water discharged from the area of the A2 motorway to the Dzierżązna river system and as a result of the SSBS system operation to Sokołówka river (Fig. 6).All the measured parameters are reduced after passing through both of systems. As a result of mechanical sedimentation the greatest reduction is suspended material transported by water – in the SSBS on average about 16% less than in untreated waters (in the Dzierżązna catchment this element was not measured). The pH of the water in both systems changes to the same extent – decreases by 10% in the Dzierżązna, and 7% in SSBS

Hydrological Effects of Urbanization: The Experience from the Sokołówka Catchment (Łódź)

This study is a part of the project The Impact of the Degree of Environment Change on the Cycle and the Quality of Water in the Urban and Suburban Catchments financed by Polish Ministry of Science and Higher Education (NCN – N 306 073340)

Springs of the Bystrzyca Dusznicka Drainage Basin

This article is an attempt of a presentation concerning the springs of the upper part of the Bystrzyca Dusznicka drainage basin against a background of the tectonic structure and geology. All the measurements and mapping of the surface hydrolographical objects were carried out in July 1993. The most important tectonic element of the researched area, which determines the spatial layout and the features of the springs, seems to be the Zieleniec overthrust consisting of the folded Proterozoik mica slates. The lower edge of its overthrust is at a height of 800 m. The rest of the drainage basin is formed of upper Cretaceous sediments dipping in the inner-Sudeten syncline. Later alpine deformations modified the geological structure of this area. The faults formed in such a way as to form 2 systems of crackings: the parallelone and slanted one running NW to SE. The Bystrzyca Dusznicka valley which runs alongside the axis of the drainage basin shows the water-gap character. In the researched area the authors observed either subsurface water in the mantle rocks, or fissure water circulating in the deeper metamorphic rocks. The upper Cretaceous porous sandstones form the most capacious underground water basin. Each water-bearing underground water horizon is separated with marly rocks. From among springs of the researched area three basic types of them were distinguished: fissure, fissure-mantle and mantle springs. Five big fissure springs ranged between 18 and 36 dm3• S-l form the source of the Bystrzyca Dusznicka river. In the drainage basin area over 100 outflows were recorded of which more than 20 were classified as spring sappings. The springs with the biggest average yield equal 2,5 dm3• S-I found in the escarpment zone of the mentioned above overthrust; whereas alongside the eastern undercut there are many small springs and spring sappings of the valley and channel character. Value of the correlation coefficient between spring water temperature and its altitude is equal to r =-0,62. It testifies to the evident inversely proportional relationship between these factors. In the upper parts of the basin fissure springs dominate whereas in the lower parts - hotter mantle ones do. At the height-interval of 700-900 m there are either mantle springs or fissure ones. The conclusions which flow from this article prove the thesis that in the mountainous areas the following factors determine the regime and localization of springs: tectonics, geology and relief of the researched area.Opracowanie niniejsze jest próbą prezentacji źródeł zlewni górnej Bystrzycy Dusznickiej na tle budowy geologicznej i tektoniki obszaru. W opracowaniu zwrócono szczególną uwagę na termikę wód źródlanych i związek występowania obszarów źródliskowych z budową geologiczną zlewni