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71.
A great step toward the improvement of safety at work was made when electrosensitive protective devices (ESPDs) were applied to the protection of press and robot-assisted manufacturing system operators. The way the device is mounted is crucial. The parameters of ESPD mounting that ensure safe distance from the controlled dangerous zone are response time, sensitivity, and the dimensions of the detection zone. The proposed experimental procedure of response time measurement is realized in two steps, with a test piece penetrating the detection zone twice. In the first step, low-speed penetration (at a speed vm) enables the detection zone border to be localized. In the second step of measurement, the probe is injected at a high speed Vd. The actuator rod position is measured and when it is equal to the value L registered by the earlier measurements, counting time begins as well as the monitoring of the state of the equipment under test (EUT) output relays. After the state changes, time tp is registered. The experimental procedure is realized on a special experimental stand. Because the stand has been constructed for certification purposes, the design satisfies the requirements imposed by Polski Komitet Normalizacyjny (PKN, 1995). The experimental results prove the measurement error to be smaller than ± 0.6 ms.  相似文献   
72.
The aim of the study was to estimate copper (Cu) accumulation efficiency in whole-fruiting bodies of 18 edible and non-edible wild growing mushrooms collected from 27 places in the Wielkopolska Voivodeship. Mushrooms were collected each time from the same places to estimate the diversity in Cu accumulation between tested mushroom species within 3 consecutive years of study (2011–2013). The study results revealed various accumulation of Cu in the whole-tested mushroom fruiting bodies. The highest mean accumulation of Cu was observed in Macrolepiota procera (119.4 ± 20.0 mg kg?1 dm), while the lowest was in Suillus luteus and Russula fellea fruiting bodies (16.1 ± 3.0 and 18.8 ± 4.6 mg kg?1 dm, respectively). Significant differences in Cu accumulation between mushroom species collected in 2011 and in the two following years (2012 and 2013) were observed. The results indicated that sporadic consumption of these mushrooms was not related to excessive intake of Cu for the human body (no toxic influence on health).  相似文献   
73.
The aim of study was to determine 9 organic acids in nine aboveground and seven wood-growing wild edible mushroom species originated from an area under the direct influence of a busy trunk road in Poland. The organic acids in the extracts of samples were identified by reversed-phase column liquid chromatography (RPLC). The presented results show that all the mushroom species were characterized by high variation in the profile and content of the analyzed acids. Each of mushroom species contained oxalic acid, the profiles of the other acids strictly depended on mushroom species. Among aboveground species, the highest total content of organic acids was found in Lepista gilva (267.5 ± 26.6 mg g?1 dry weight (DW)), while Laccaria amethystina was characterized by the lowest content (37.7 ± 6.5 mg g?1 DW). Within wood-growing species, the highest content of organic acids was determined in Flammulina velutipes (171.9 ± 26.7 mg g?1 DW), whereas the lowest content (34.2 ± 2.9 mg g?1 DW) of the studied acids was observed in Grifola frondosa.  相似文献   
74.
The study assesses halogenated volatile organic compound concentrations in the water and wastewater streams of a petrochemical plant. Water samples were collected at 11 sampling points during 5 sampling campaigns. The samples were collected from the oil dewaxing unit and in the wastewater treatment plant. Dichloromethane and 1,2-dichloroethane were the most frequently determined compounds. Tetrachloroethene was also detected at the wastewater treatment plant inlets. The concentrations of halogenated volatile organic compounds dropped significantly at wastewater discharge points compared to wastewater treatment plant inlets. The application of 1,2-dichloroethane/dichloromethane ratio as a tool to assess evaporation processes is discussed.  相似文献   
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The aim of this article is to evaluate selected tourism development strategies in Poland, in the context of strategic planning, stakeholders’ participation, and sustainable development principles. A questionnaire evaluation of strategy (44 questions) was established and based on measurement scales developed and validated by other authors in earlier studies. The five authors of the study rated 37 tourism development strategies in 13 provinces, 11 cities, 5 counties, 6 municipalities, and 2 other areas. Analysis revealed that they implement paradigms of sustainable development of tourism to only a small extent. Definitely higher quality is documented for higher levels of administrative division. The highest rated domains of the tourism development strategy in the examined documents are Strategic Planning Indicators and Implementation, Monitoring, and Evaluation.  相似文献   
79.
Environmental Science and Pollution Research - The maximisation of the efficiency of the photovoltaic system is crucial in order to increase the competitiveness of this technology. Unfortunately,...  相似文献   
80.
The paper presents the first report on the application of a lead film electrode for the determination of ultratrace concentrations of platinum. The procedure is based on preconcentration of the Pt(IV)-formaldehyde complexes at an in situ plated lead film electrode held at ?0.9 V (vs. Ag/AgCl), followed by a negatively sweeping differential pulse voltammetric scan. The composition of the supporting electrolyte, the influence of accumulation potential and time on the sensitivity of platinum responses are discussed. The detection limit of Pt(IV) with the accumulation time of 60 was equal to 9.2?×?10?12 mol L?1. The application of this method was tested by recovery of Pt(IV) from spiked environmental water samples.  相似文献   
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