Nitrogen and phosphorus budgets for Iowa and Iowa watersheds

https://ir.uiowa.edu/igs_tis/1046/thumbnail.jp

Autonomous photovoltaic system for night-time lighting in the stable

ArticleAutonomous photovoltaic (PV) systems are suitable, for example, for powering various appliances or scientific instruments in the field, for automatic data collection, for signaling, etc. At the Czech University of Life Sciences Prague, we have designed an experimental autonomous PV system designed for night-time lighting for orientating in a stable for horses. The article describes the construction of a PV system with a PV panel rated at 170 Wp, with a lead-acid accumulator and a 1,5 W LED light source. The data collection was automated. The data evaluation shows that during the whole year, the PV system has been recharged and there was no lighting failure. The paper also presents important measured characteristics

Operation of the photovoltaic system in Prague and data evaluation

Received: January 6th, 2021 ; Accepted: April 7th 2021 ; Published: April 12th 2021 ; Correspondence: [email protected] on-grid photovoltaic system was installed at the Faculty of Engineering in 2015. The monitoring system developed in our laboratory monitors data and can also detect failure and type of failure. The evaluation of the data shows that the amount of electricity produced slightly exceeds the expected values predicted by the internationally used internet application PVGIS. The effect of the aging of PV panels has so far had a minimal effect on the electricity produced. Immediate output power is affected by multiple parameters. Higher temperatures reduce the efficiency of energy conversion, so in summer the instantaneous power may be lower even at higher radiation intensity and smaller angle of incidence

Design and data comparison of the photovoltaic power plants in the southern and northern hemispheres

We have recently developed a unique monitoring system for photovoltaic power plants and have gradually improved it in recent years. The system is installed at about 80 power plants in several European countries and at one power plant in Chile. We collect and evaluate all data in our laboratory. In this paper we describe the unique design of a photovoltaic power plant in the southern hemisphere in Chile with photovoltaic panels installed on tracking stands. We present the evaluated data and we discuss their comparison with photovoltaic power plants installed in Europe. We also discuss different solar conditions of these locations

Potential for Geologic Sequestration of CO2 in Iowa

https://ir.uiowa.edu/igs_tis/1056/thumbnail.jp

Modeling the water demand on farms

The decreasing availability of water caused by depletion and climate change combined with a growing world population requires the productive use of water now and in the future. The young researcher group "AgroHyd" at the Leibniz-Institute for Agricultural Engineering Potsdam-Bornim (ATB) is currently modeling the water demand for agricultural processes at the farm scale and developing indicators to link the hydrological and agricultural perspectives. The aim of the group is to increase productivity in agriculture by raising water productivity in plant production and livestock farming. The effects of various agronomic measures, individual and in combination, on water productivity are assessed using several indicators. Scenarios of agricultural measures, climate and diets are used to test to what extent the water demand for food production will increase due to growing global change in different regions of the world

Total nut, tree nut, and peanut consumption and metabolic status in southern Italian adults

Background: Nut consumption has been associated with cardio-metabolic health benefits. However, studies conducted in the Southern Italian population, where adherence to the Mediterranean diet has been reported being relatively high, are rather scarce. The aim of this study was to test the association between consumption of total and specific types of nuts and metabolic status among adults living in Sicily, Southern Italy. Methods: Demographic and dietary characteristics of 2044 adults living in Southern Italy were analyzed. Multivariate logistic regression analyses were performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of the association between nut consumption and metabolic status adjusting for potential confounding factors. Results: The energy-adjusted model revealed that higher nut intake was inversely associated with occurrence of hypertension, type-2 diabetes, and dyslipidemia. However, the association did not remain significant for the latter after adjusting for the main background characteristics, while an inverse association was stably confirmed for hypertension (OR = 0.61, 95% CI: 0.46–0.80 and OR = 0.44, 95% CI: 0.26–0.74, respectively) even after adjusting for adherence to the Mediterranean diet. Among individual nut types, most of the associations were null except for higher almond intake, which was inversely associated with occurrence of hypertension (OR = 0.70, 95% CI: 0.49–0.99). Conclusions: Higher nut consumption is associated with overall better metabolic status in individuals living in the Mediterranean area

Production of ethanol from livestock, agricultural, and forest residuals: An economic feasibility study

In this study, the economic feasibility of producing ethanol from gasification followed by syngas fermentation via commercially available technologies was theoretically evaluated using a set of selected livestock and agricultural and forest residuals ranging from low valued feedstocks (i.e., wood, wheat straw, wheat straws blended with dewatered swine manure, and corn stover) to high valued oilseed rape meal. A preliminary cost analysis of an integrated commercial system was made for two cases, a regional scale 50 million gallon (189,271 m3) per year facility (MGY) and a co-op scale 1–2 MGY facility. The estimates for the minimum ethanol selling prices (MESP) depend heavily on the facility size and feedstock costs. For the 1–2 MGY (3785–7571 m3/y) facility, the MESP ranged from $5.61–$7.39 per gallon ($1.48–$1.95 per liter) for the four low-value feedstocks. These high costs suggest that the co-op scale even for the low-value feedstocks may not be economically sustainable. However, the MESP for the 50 MGY facility were significantly lower and comparable to gasoline prices ($2.24–$2.96 per gallon or $0.59–$0.78 per liter) for these low-value feedstocks, clearly showing the benefits of scale-up on construction costs and MESP. © 2019 by the authors. Licensee MDPI, Basel, Switzerland

Short-term and long-term effects of natural and artificial carbonaceous substrates on greenhouse gas fluxes.

The emissions of two greenhouse gases (GHG), carbon dioxide (CO2) and nitrous oxide (N2O), from six substrates with different carbonaceous content were compared in short and long-term incubation experiments. Three natural soils and three artificial chars were mixed with carbon (C) poor soil (Cambisol) to simulate real conditions after application of char to farmland. The natural soils were a Cambisol, an Anthrosol and a Histosol with C contents of 1.3%, 4.4% and 13.2%, respectively. The three chars produced through thermal conversion of wood chips by hydrothermal carbonisation (HTC), fluidized bed gasification and pyrolysis had C contents of 56.9%, 75.4% and 79.9%, respectively. Emission rates of CO2 and N2O from the rewetted substrates were measured by gas chromatography over a short time of 72 h and over a long period of nearly two years. The short-term CO2 emissions from the natural soils showed a clear relationship to their C content. The emission rate for the Histosol/Cambisol mixture was three times higher than that for the pure Cambisol, 77.1 vs. 23.5 mg CO2-C kg(-1) organic matter (OM) per hour. The C emission rates for the char/Cambisol mixtures were much lower, ranging between 3.0 and 9.1 mg CO2-C kg OM-1 h(-1), and did not correspond to their total C contents. Comparison between the two incubation lengths showed that the long-term CO2 emission rates were generally one order of magnitude lower than the short-term rates. The final emission rates for natural substrates over a period of two years were still twice those for artificial char substrates, between 2.2-3.5 mg CO2-C kg OM-1 h(-1), and 1.3-1.8 mg CO2-C kg OM-1 respectively. Although the contents of total nitrogen (N-tot) and extractable nitrogen (N-min) were con siderable in the chars under study, enhanced N2O release was not observed in the incubation experiments. Instead, N2O emission rates in the three mixtures of chars and Cambisol were lower by one to two orders of magnitude compared to the pure Cambisol in short-term incubations. Even long-term N(2)O( )emissions were 5 to 9 times lower. The highest degree of N2O reduction was found for the HTC char. Because of the high global warming potential of N2O, this positive effect of chars may play an important role in mitigating emissions of CO2 equivalents. Both CO2 and N2O must be taken into account when balancing GHG emitted after chars (biochar, gasifier char, HTC char) are applied to soil

Association between Nutrient-Based Dietary Patterns and Bladder Cancer in Italy

Limited knowledge is available on dietary patterns and bladder cancer risk. We analyzed data from an Italian case-control study carried out between 2003 and 2014, including 690 incident bladder cancer cases and 665 hospital-controls. We derived nutrient-based dietary patterns applying principal component factor analysis on 28 selected nutrients. We categorized factor scores according to quartiles, and estimated the odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) through logistic regression models, adjusted for major confounding factors. We identified four dietary patterns named "Animal products", "Vitamins and fiber", "Starch-rich", and "Animal unsaturated fatty acids". We found an inverse association between the "Vitamins and fiber" pattern and bladder cancer (OR = 0.70, 95% CI: 0.48-0.99, IV versus I quartile category). Inverse relationships of borderline significance were also found for the "Animal products" and the "Animal unsaturated fatty acids" dietary patterns. No significant association was evident for the "Starch-rich" pattern. The current study allowed us to identify major dietary patterns in this Italian population. Our study confirms available evidence and shows that scoring high on a fruit-and-vegetables pattern provides beneficial effects on bladder cancer risk