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The need for an improved control strategy for the operation of a wind-powered refrigeration system for the storage of apples was investigated. The results are applicable to other systems which employ intermittently available power sources, battery and thermal storage, and an auxiliary, direct current power supply. Tests were conducted on the wind-powered refrigeration system at the Virginia Polytechnic Institute and State University Horticulture Research Farm in Blacksburg, Virginia. Tests were conducted on the individual components of the system. In situ windmill performance were also conducted. The results of these tests have been presented. An improved control strategy was developed to improve the utilization of available wind energy and to reduce the need for electrical energy from an external source while maintaining an adequate apple storage environment. Ph. D.

The need for an improved control strategy for the operation of a wind-powered refrigeration system for the storage of apples was investigated. The results are applicable to other systems which employ intermittently available power sources, battery and thermal storage, and an auxiliary, direct current power supply. Tests were conducted on the wind-powered refrigeration system at the Virginia Polytechnic Institute and State University Horticulture Research Farm in Blacksburg, Virginia. Tests were conducted on the individual components of the system. In situ windmill performance were also conducted. The results of these tests have been presented. An improved control strategy was developed to improve the utilization of available wind energy and to reduce the need for electrical energy from an external source while maintaining an adequate apple storage environment. Ph. D.

Owing to their high luminous efficiency and tunable emission in both red light and far-red light regions, Mn4+ ion-activated phosphors have appealed significant interest in photoelectric and energy conversion devices such as white light emitting diode (W-LED), plant cultivation LED, and temperature thermometer. Up to now, Mn4+ has been widely introduced into the lattices of various inorganic hosts for brightly red-emitting phosphors. However, how to correlate the structure-activity relationship between host framework, luminescence property, and photoelectric device is urgently demanded. In this review, we thoroughly summarize the recent advances of Mn4+ doped phosphors. Meanwhile, several strategies like co-doping and defect passivation for improving Mn4+ emission are also discussed. Most importantly, the relationship between the protocols for tailoring the structures of Mn4+ doped phosphors, increased luminescence performance, and the targeted devices with efficient photoelectric and energy conversion efficiency is deeply correlated. Finally, the challenges and perspectives of Mn4+ doped phosphors for practical applications are anticipated. We cordially anticipate that this review can deliver a deep comprehension of not only Mn4+ luminescence mechanism but also the crystal structure tailoring strategy of phosphors, so as to spur innovative thoughts in designing advanced phosphors and deepening the applications.

Owing to their high luminous efficiency and tunable emission in both red light and far-red light regions, Mn4+ ion-activated phosphors have appealed significant interest in photoelectric and energy conversion devices such as white light emitting diode (W-LED), plant cultivation LED, and temperature thermometer. Up to now, Mn4+ has been widely introduced into the lattices of various inorganic hosts for brightly red-emitting phosphors. However, how to correlate the structure-activity relationship between host framework, luminescence property, and photoelectric device is urgently demanded. In this review, we thoroughly summarize the recent advances of Mn4+ doped phosphors. Meanwhile, several strategies like co-doping and defect passivation for improving Mn4+ emission are also discussed. Most importantly, the relationship between the protocols for tailoring the structures of Mn4+ doped phosphors, increased luminescence performance, and the targeted devices with efficient photoelectric and energy conversion efficiency is deeply correlated. Finally, the challenges and perspectives of Mn4+ doped phosphors for practical applications are anticipated. We cordially anticipate that this review can deliver a deep comprehension of not only Mn4+ luminescence mechanism but also the crystal structure tailoring strategy of phosphors, so as to spur innovative thoughts in designing advanced phosphors and deepening the applications.

The objective of the study was to evaluate the effect of two types of treated sewage sludge as soil amendment, composted with pruning wastes (CP) and thermally dried (ST) on the production of ten woody perennials species for energy purposes. The species used were: Paulownia tomentosa (princess tree), Populus x euramericana (Canadian poplar), Ulmus minor (field elm, tree clones), Ulmus laevis (European white elm), Prunus x amygdalo-persica (adafuel), Tamarix gallica (tamarisk), Salix alba (white willow) and Platanus x hispanica (plane tree). The increase in plant growth three years after amendment application is evaluated with the aim to analyze the long term effect of the treated sewage sludges application on plant production. In general, the plants developed in the soils treated with ST sludge present the highest values of growth (diameter, height and width), which can be due to the faster supply of nitrogen from this material. However, the growth rate was higher in the CP treatment for the most of the species due to a continuous release of nutrients from the CP degradation. In this sense, the effect of CP treatment on plant production would be observed at the longer time than the ST one. Proceedings of the 26th European Biomass Conference and Exhibition, 14-17 May 2018, Copenhagen, Denmark, pp. 369-373

The objective of the study was to evaluate the effect of two types of treated sewage sludge as soil amendment, composted with pruning wastes (CP) and thermally dried (ST) on the production of ten woody perennials species for energy purposes. The species used were: Paulownia tomentosa (princess tree), Populus x euramericana (Canadian poplar), Ulmus minor (field elm, tree clones), Ulmus laevis (European white elm), Prunus x amygdalo-persica (adafuel), Tamarix gallica (tamarisk), Salix alba (white willow) and Platanus x hispanica (plane tree). The increase in plant growth three years after amendment application is evaluated with the aim to analyze the long term effect of the treated sewage sludges application on plant production. In general, the plants developed in the soils treated with ST sludge present the highest values of growth (diameter, height and width), which can be due to the faster supply of nitrogen from this material. However, the growth rate was higher in the CP treatment for the most of the species due to a continuous release of nutrients from the CP degradation. In this sense, the effect of CP treatment on plant production would be observed at the longer time than the ST one. Proceedings of the 26th European Biomass Conference and Exhibition, 14-17 May 2018, Copenhagen, Denmark, pp. 369-373

The climatic, energetic and political context promotes the development of bioenergies. However we have a lack of knowledge to find out the best energy crops, depending on the soil, the climate and the end­use. This work aimed at studying the adaptation and the biomass and biofuel yield, of several energy crops grown in France in different soil and climate conditions. The biomass yields were very variable between the different experimental sites and no differences were observed on the median biomass yield between crops. Moreover, there was no evidence of a highly productive crop in all the conditions of soil and climate. Because of little differences of the lower heating value between crops, no differences were observed on the primary energy yield. The ethanol yield per hectare was higher for miscanthus, switchgrass and fiber sorghum because of higher cellulose content in these crops. The nitrogen removed at harvest by miscanthus and switchgrass were significantly lower than the other crops witch could lead to reduced fertilizer­N requirements. Further research are needed to clarify the effect of limiting factors on the biomass yield of the different energy crops and to consider other parameters such as the environmental impacts to give rules to choose the most suitable crop in a given region. Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 269-272

The climatic, energetic and political context promotes the development of bioenergies. However we have a lack of knowledge to find out the best energy crops, depending on the soil, the climate and the end­use. This work aimed at studying the adaptation and the biomass and biofuel yield, of several energy crops grown in France in different soil and climate conditions. The biomass yields were very variable between the different experimental sites and no differences were observed on the median biomass yield between crops. Moreover, there was no evidence of a highly productive crop in all the conditions of soil and climate. Because of little differences of the lower heating value between crops, no differences were observed on the primary energy yield. The ethanol yield per hectare was higher for miscanthus, switchgrass and fiber sorghum because of higher cellulose content in these crops. The nitrogen removed at harvest by miscanthus and switchgrass were significantly lower than the other crops witch could lead to reduced fertilizer­N requirements. Further research are needed to clarify the effect of limiting factors on the biomass yield of the different energy crops and to consider other parameters such as the environmental impacts to give rules to choose the most suitable crop in a given region. Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 269-272

The paper aims to achieve a definition of the concept of sustainability and of sustainable system from a logical perspective. In this respect, it introduces and defines (through the sufficiency predicates) the concept of logically vivid system and, on this basis, are discussed a logical concept of sustainability, respectively of a sustainable system in general are discussed and built up. Sustainability is considered in light of identity preservation of the systems, as a static anchor, on one hand, and of the concept of automatic stabilizers as a dynamic anchor on the other side. Finally, the two sufficiency conditions for a logically vivid system be sustainable are identified: the presence of hyper-cycles, respectively the absence of positive feed-back.

The paper aims to achieve a definition of the concept of sustainability and of sustainable system from a logical perspective. In this respect, it introduces and defines (through the sufficiency predicates) the concept of logically vivid system and, on this basis, are discussed a logical concept of sustainability, respectively of a sustainable system in general are discussed and built up. Sustainability is considered in light of identity preservation of the systems, as a static anchor, on one hand, and of the concept of automatic stabilizers as a dynamic anchor on the other side. Finally, the two sufficiency conditions for a logically vivid system be sustainable are identified: the presence of hyper-cycles, respectively the absence of positive feed-back.