43 research outputs found
Effects of egg size on length, weight, growth and survival of prelarval and early feeding stage of Persian sturgeon (Acipenser persicus)
A study was conducted on the effects of egg size on length, weight, growth and survival of prelarval and early feeding stages of 19 female breeders of Persian sturgeon. The results showed that egg size can affect the total length and weight of prelarvae and there were positive and significant correlation between egg size and total length of prelarvae at the hatching stage and at 2,4,6,8 and 10 days post hatching (P<0.05). There were also positive and significant correlation between egg size and volume of yolk sac at hatching (P<0.05). However, during the first feeding stage the correlation between egg size and survival was very weak
Using sterile insect technique against Carob moth, Ectomyelois ceratoniae (Zeller) (Lep.: Pyralidae), in Yazd province, Iran
Carob moth, Ectomyelois ceratoniae (Zeller) (Lep.: Pyralidae), is the most important pest of pomegranate fruit in Iran where the cryptic activity of its larva makes the application of insecticides practically impossible. In this research, we evaluated the viability of the sterile insect technique against the carob moth in two isolated regions in Yazd province (Aqda and Mehriz). The mass rearing of the pest was performed in clean rooms on artificial diet under environmental conditions, 29±1 ºC and 75±5 %RH applying 165 Gy gamma ray as sterilizing doze. The sterile insects were released periodically in Aqda orchards (45 hectares) and in Chah Sheida (12 hectares) in Mehriz between March and November 2015. The infestation rate of carob moth in Aqda and Mehriz significantly reduced, in both target regions and control areas, by 12.27% and 44.02%, as well as 12.06% and 50.11%, for Aqda and Mehriz, respectively. It was concluded that periodical release of sterile carob moths can effectively lower the density of pest population and its economic loss on the harvest
Inter-seasonal compressed air energy storage using saline aquifers
Meeting inter-seasonal fluctuations in electricity production or demand in a system dominated by renewable energy requires the cheap, reliable and accessible storage of energy on a scale that is currently challenging to achieve. Commercially mature compressed-air energy storage could be applied to porous rocks in sedimentary basins worldwide, where legacy data from hydrocarbon exploration are available, and if geographically close to renewable energy sources. Here we present a modelling approach to predict the potential for compressed-air energy storage in porous rocks. By combining this with an extensive geological database, we provide a regional assessment of this potential for the United Kingdom. We find the potential storage capacity is equivalent to approximately 160% of the United Kingdom’s electricity consumption for January and February 2017 (77–96 TWh), with a roundtrip energy efficiency of 54–59%. This UK storage potential is achievable at costs in the range US$0.42–4.71 kWh−1
Polymorphism and magnetic properties of Li2MSiO4 (M 5 Fe, Mn) cathode materials
Transition metal-based lithium orthosilicates (Li2MSiO4,M=Fe, Ni, Co, Mn) are gaining a wide interest as
cathode materials for lithium-ion batteries. These materials present a very complex polymorphism that
could affect their physical properties. In this work, we synthesized the Li2FeSiO4 and Li2MnSiO4 compounds
by a sol-gel method at different temperatures. The samples were investigated by XRPD, TEM, 7Li MAS
NMR, and magnetization measurements, in order to characterize the relationships between crystal structure
and magnetic properties. High-quality 7Li MAS NMR spectra were used to determine the silicate structure,
which can otherwise be hard to study due to possible mixtures of different polymorphs. The magnetization
study revealed that the Neel temperature does not depend on the polymorph structure for both iron and
manganese lithium orthosilicates