A long-term analysis of the declining population of the Egyptian vulture in the Italian peninsula: Distribution, habitat preference, productivity and conservation implications

Between the beginning of the 1970s and the early 1990s the breeding population of the Egyptian vulture (Neophron percnopterus) in the Italian peninsula declined from 29 to nine breeding pairs. We analysed the main aspects of the decline of this population during the last 30 years, namely: (1) landscape structure and composition of active and extinct nesting sites; (2) changes in the land use and number of cattle within the breeding range; (3) productivity (1986-1999) of the last nine pairs breeding in the Italian peninsula. Further decline in the breeding population was probably stopped by creating artificial feeding sites and protecting the last nesting sites from direct persecution. Nearly two-thirds of the pairs laid at least one egg per year, and half of the pairs fledged at least one young per year. The mean number of fledged young was 0.99±0.66 per breeding pair, and 1.27±0.45 per successful pair. About 75% of the breeding failures occurred during incubation, and 71% were related to human activities and direct persecution. The nesting cliff occupation rate, percentage of breeding attempts that fledged at least one chick and mean number of fledged young were negatively correlated with the distance to an artificial feeding site. © 2001 Elsevier Science Ltd. All rights reserved.Peer Reviewe

Radar-absorbent properties of a foam glass with gallium arsenide addition

The principal possibility of using wastes of semiconductor devices production containing gallium arsenide as a component of radio-absorbing material was established. The composition formulation including perlite, liquid glass, complex blowing agent and waste is developed. It is shown that with increase the waste amount in the composition from 10 to 30 wt. % the absorption coefficient increases from 80 to 98%, the transmission coefficient decreases to zero. The obtained results indicate a high absorbing capacity of composite in the frequency range of 120 - 260 GHz that refers to ultrasonic waves

Твердофазно-спектрофотометрическое определение ртути с использованием дифенилкарбазона

Объектом исследования является полимерный датчик с иммобилизированным реагентом для определения ионов ртути. Целью работы является создание оптического сенсора для твёрдофазно-спектрофотометрического определения ртути на основе полимерной матрицы. В процессе выполнения магистерской диссертации проведен анализ существующих методов определения ртути, проверена возможность применения твердофазной спектрофотометрии для определения ионов ртути, подобраны оптимальные условия иммобилизации реагента (время, pH), получены калибровочные зависимости, рассмотрены вопросы ресурсоэффективности и безопасности данного исследования.The object of the study is a polymer sensor with an immobilized reagent for the determination of mercury ions. The aim of the work is to create an optical sensor for solid-phase-spectrophotometric determination of mercury based on a polymer matrix. During execution master thesis analyzed existing mercury determination methods verified the possibility of applying solid phase spectrophotometry to determine the mercury ions, optimal conditions are selected immobilization reagent (time, pH), prepared according to the calibration, the issues of security and resource efficiency of the study

A design approach for adsorption energy systems integrating dynamic modeling with small-scale experiments

Adsorption energy systems can be driven by thermal energy from waste heat or the sun and thereby allow reducing fossil energy consumption and thus reduce global greenhouse gas emissions. Adsorption heat pumps and chillers can provide heating or cooling, adsorption thermal energy storage allows storing thermal energy. However, adsorption energy systems suffer from high investment costs due to low performance. Performance of adsorption energy systems strongly depends on the equilibrium properties of the working pair as well as heat and mass transfer mechanisms of the adsorption material in the adsorption energy system (adsorbent configuration).Evaluating new working pairs and adsorbent configurations is rather challenging: While the working pair's equilibrium properties can be determined with standardized measurement equipment, heat and mass transfer mechanisms cannot easily be determined, since they strongly depend on the full-scale adsorption energy system. Construction and operation of full-scale experiments requires high effort. Besides, often only small amounts of an adsorbent configuration are available, which are insufficient for full-scale experiments. To resolve these drawbacks, this thesis provides and validates a comprehensive method to determine the performance of working pairs and adsorbent configurations in adsorption energy systems from simple small-scale experiments. As a representative class of adsorption energy systems, adsorption chillers are investigated in this thesis. A small-scale Large-Temperature-Jump experiment is combined with dynamic modeling of the transient heat and mass transfer processes. Additionally, the experiment is extended by an infrared camera. The additional temperature information allows to distinguish and to determine the time-resolved effective heat transfer coefficient and diffusion coefficient in the heat and mass transfer model. The heat transfer and diffusion coefficients are inserted into a full-scale adsorption chiller model to predict the performance. Exemplarily, a commercial available silica gel and the adsorbent class of metal-organic frameworks (MOFs) are evaluated for an adsorption chiller application. The method is validated with experimental data of a full-scale prototype adsorption chiller and shows high accuracy. Furthermore, the method allows optimizing the adsorption chiller for a given working pair or adsorbent configuration and allows identifying bottlenecks and potential for improvement of the working pairs. In summary, this thesis bridges the gap between small-scale experiments and modeling of full-scale adsorption energy systems. The method allows for a comprehensive and reliable evaluation of working pairs and adsorbent configurations for adsorption energy systems