23 research outputs found
Multi-variant analysis of the geothermal heating system in Konstantynów Łódzki
W artykule przedstawiono informacje geologiczne i hydrogeologiczne o poziomach wód geotermalnych w rejonie miasta Konstantynów Łódzki, w aspekcie wykorzystania ich dla celów ciepłowniczych. Jako najbardziej przydatny do tych celów wytypowano zbiornik jury dolnej. Opracowany wielowariantowy model źródła energii zawierał następujące elementy: bezpośredni wymiennik ciepła geotermalnego, pompy ciepła absorpcyjne albo sprężarkowe (alternatywnie) oraz przyłącze do istniejącej sieci ciepłowniczej. Najlepszym wariantem energetycznym był wariant zakładający włączenie do systemu części odbiorców systemu ciepłowniczego miasta Łodzi. W aspekcie ekonomicznym najlepszy okazał się wariant zakładający wykorzystanie energii geotermalnej przy wspomaganiu pomp ciepła przez Konstantynów Łódzki i przejęcie części odbiorców zasilanych z miejskiej sieci ciepłowniczej poza sezonem grzewczym. Wszystkie analizowane warianty wykorzystania energii geotermalnej dla Konstantynowa Łódzkiego zakładające wykorzystanie energii geotermalnej uzyskały pozytywny efekt ekologiczny w postaci redukcji emisji zanieczyszczeń.The article presents geological and hydrogeological information on geothermal waters in the area of the city of Konstantynów Łódzki, in terms of their use for heating purposes. The Lower Jurassic aquifer was selected for this purpose. The developed multi-variant power source model included the following: a direct geothermal heat exchanger, an absorption or compressor heat pump (alternatively) and a connection to an existing district heating network. The best was the option of incorporating into the system some of the recipients of the heating system of the city of Lodz into the system. In the economic aspect, the best option was the use of geothermal energy supported by heat pumps – by Konstantynów Łódzki and the takeover of part of the customers supplied from the district heating network outside the heating season. All the analyzed variants of geothermal energy used for Konstantynów Łódzki assuming the use of geothermal energy have gained a positive ecological effect in the form of the reduction of pollutant emissions
Characterization of natural gas by Raman spectroscopy and its application for in-situ measurements
Gaseous hydrocarbons and nitrogen mixtures are characterized with an own designed portable Raman system equipped with a high pressure autoclave and fiber-optic probe. Backscattered radiation is collected through a sapphire window with a probe and transferred to the spectrometer. Samples are measured for a set of pressures in the range of 1–150 bar in ambient temperature. Measurement conditions are set to maintain an one-phase system. Spectra are collected in a wide range of wavenumber 350–3500 cm–1. Initial composition of measured samples is measured be means of gas chromatography. Design computer algorithms automatically detects and characterizes Raman bands for given species and their peak areas. The influence of both pressure and concentration of a given element on given band position and area are demonstrated
Application of Raman spectroscopy analysis in unconventional natural gas reservoirs – density and pressure dependence on Raman signal intensity
This paper contains information about Raman spectroscopy, describing its possible application in the oil and gas industry. This method allows the performance of a series of repetitive measurements to determine the composition of samples and its changes with high accuracy. In the article, the data presented in the literature connected with Raman spectroscopy and the oil and gas industry is analyzed. This paper considered measurements of a natural gas composition in simulated in-situ conditions performed using Raman spectroscopy. The current research project is trying to develop a mobile apparatus which would use Raman spectroscopy for defining reservoir fluid compounds in high pressure and high temperature conditions. The preliminary measurements were carried out in the simulated in-situ in variant pressure conditions
Damage Trajectories in Systemic Sclerosis Using Group-Based Trajectory Modeling
First published: 28 February 2022Objective. Systemic sclerosis (SSc) is an autoimmune disease characterized by progressive organ damage, which can be measured using the Scleroderma Clinical Trials Consortium Damage Index (SCTC-DI). We aimed to identify whether distinct trajectories of damage accrual exist and to determine which variables are associated with different trajectory groups. Methods. Incident cases of SSc (<2 years) were identified in the Australian Scleroderma Interest Group and Canadian Scleroderma Research Group prospective registries. Group-based trajectory modeling was used to identify SCTC-DI trajectories over the cohort’s first 5 annual visits. Baseline variables associated with trajectory membership in a univariate analysis were examined in multivariable models. Results. A total of 410 patients were included. Three trajectory groups were identified: low (54.6%), medium (36.2%), and high (10.3%) damage. Patients with faster damage accrual had higher baseline SCTC-DI scores. Older age (odds ratio [OR] 1.57 [95% confidence interval (95% CI) 1.18–2.10]), male sex (OR 2.55 [95% CI 1.10–5.88]), diffuse disease (OR 6.7 [95% CI 2.57–17.48]), tendon friction rubs (OR 5.4 [95% CI 1.86–15.66]), and elevated C-reactive protein level (OR 1.98 [95% CI 1.49–2.63]) increased the odds of being in the high-damage group versus the reference (low damage), whereas White ethnicity (OR 0.31 [95% CI 0.12–0.75]) and anticentromere antibodies (OR 0.24 [95% CI 0.07–0.77]) decreased the odds. Conclusion. We identified 3 trajectories of damage accrual in a combined incident SSc cohort. Several characteristics increased the odds of belonging to worse trajectories. These findings may be helpful in recognizing patients in whom early aggressive treatment is necessary.Ariane Barbacki, Murray Baron, Mianbo Wang, Yuqing Zhang, Wendy Stevens, Joanne Sahhar, Susanna Proudman, Mandana Nikpour, and Ada Man, on behalf of the Australian Scleroderma Interest Group and the Canadian Scleroderma Research Grou