As an alternative to conventional encapsulation concepts for a double glass photovoltaic(PV)module,we introduce an innovative ionomer-based multi-layer encapsulant,by which the application of additional edge sealing t...As an alternative to conventional encapsulation concepts for a double glass photovoltaic(PV)module,we introduce an innovative ionomer-based multi-layer encapsulant,by which the application of additional edge sealing to prevent moisture penetration is not required.The spontaneous moisture absorption and desorption of this encapsulant and its raw materials,poly(ethylene-co-acrylic acid)and an ionomer,are analyzed under different climatic conditions in this work.The relative air humidity is thermodynamically the driving force for these inverse processes and determines the corresponding equilibrium moisture content(EMC).Higher air humidity results in a larger EMC.The homogenization of the absorbed water molecules is a diffusion-controlled process,in which temperature plays a dominant role.Nevertheless,the diffusion coefficient at a higher temperature is still relatively low.Hence,under normal climatic conditions for the application of PV modules,we believe that the investigated ionomer-based encapsulant can“breathe”the humidity:During the day,when there is higher relative humidity,it“inhales”(absorbs)moisture and restrains it within the outer edge of the module;then at night,when there is a lower relative humidity,it“exhales”(desorbs)the moisture.In this way,the encapsulant protects the cell from moisture ingress.展开更多
Moisture sorption isotherms and thermodynamic properties of Camellia oleifera seeds as influenced by oil content were investigated.Moisture desorption and adsorption isotherms of Camellia oleifera seeds,kernels and sh...Moisture sorption isotherms and thermodynamic properties of Camellia oleifera seeds as influenced by oil content were investigated.Moisture desorption and adsorption isotherms of Camellia oleifera seeds,kernels and shells from three varieties were determined using constant temperature and humidity chamber method at different temperatures(10°C,25°C,and 40°C)with water activity ranging from 0.20 to 0.90.Six selected mathematic models were employed to fit the experimental data.The Peleg model gave the best results for both seeds and kernels and Langmuir model was the best for shells.The difference of equilibrium moisture contents at the same water activities during desorption and adsorption indicated the occurrence of hysteresis of adsorption processes and the equilibrium moisture contents tended to decrease with the increasing oil content and temperature.The binding energy and average capacity per unit mass decreased with increasing temperature and oil content.The relationships between water activity and the logarithm of sorption activity showed the capillary porous body characteristics of the seeds.展开更多
文摘As an alternative to conventional encapsulation concepts for a double glass photovoltaic(PV)module,we introduce an innovative ionomer-based multi-layer encapsulant,by which the application of additional edge sealing to prevent moisture penetration is not required.The spontaneous moisture absorption and desorption of this encapsulant and its raw materials,poly(ethylene-co-acrylic acid)and an ionomer,are analyzed under different climatic conditions in this work.The relative air humidity is thermodynamically the driving force for these inverse processes and determines the corresponding equilibrium moisture content(EMC).Higher air humidity results in a larger EMC.The homogenization of the absorbed water molecules is a diffusion-controlled process,in which temperature plays a dominant role.Nevertheless,the diffusion coefficient at a higher temperature is still relatively low.Hence,under normal climatic conditions for the application of PV modules,we believe that the investigated ionomer-based encapsulant can“breathe”the humidity:During the day,when there is higher relative humidity,it“inhales”(absorbs)moisture and restrains it within the outer edge of the module;then at night,when there is a lower relative humidity,it“exhales”(desorbs)the moisture.In this way,the encapsulant protects the cell from moisture ingress.
基金The authors acknowledge that this work was financially supported by the Gannan Oil Tea Camellia Industry Collaborative Innovation Center(Grant No.YP201610).
文摘Moisture sorption isotherms and thermodynamic properties of Camellia oleifera seeds as influenced by oil content were investigated.Moisture desorption and adsorption isotherms of Camellia oleifera seeds,kernels and shells from three varieties were determined using constant temperature and humidity chamber method at different temperatures(10°C,25°C,and 40°C)with water activity ranging from 0.20 to 0.90.Six selected mathematic models were employed to fit the experimental data.The Peleg model gave the best results for both seeds and kernels and Langmuir model was the best for shells.The difference of equilibrium moisture contents at the same water activities during desorption and adsorption indicated the occurrence of hysteresis of adsorption processes and the equilibrium moisture contents tended to decrease with the increasing oil content and temperature.The binding energy and average capacity per unit mass decreased with increasing temperature and oil content.The relationships between water activity and the logarithm of sorption activity showed the capillary porous body characteristics of the seeds.
