جستجوی مقالات مرتبط با کلیدواژه « Metal ions » در نشریات گروه « کشاورزی »

Interaction of floral pigments with metal ions can alter the final color of the petals. Metal ions can affect stability of flowers final color by altering vacuolar pH and activity of enzymes involved in biosynthesis، destruction، accumulation and transition of pigments. In this study، contents of metal ions of petal tissue and their relationships with parameters of petal color analyzed and compared in stage of full blooming in six varieties Gerbera with different colors. Investigation on metal ion contents in different varieties didn''t show statistically significant difference in Cu2+ content. Results showed that enhancement of Fe2+ content in petals increased a* and C* parameters and decreased L* value. Also، reduction of Zn2+ amounts in petal tissue increased h* value. Unlike Ca2+، a positive significant difference observed between Mg2+ contents and parameters of C* and a*، also a negative significant difference between Mg2+ content and L* value. Ions of Fe2+، Ca2+ and Mg2+ presented more effective relationship with flower color parameters. Concentration of Fe2+، Cu2+، Zn2+، Mn2+، Ca2+ and Mg2+ in petal tissue were ranged to 0. 0076-0. 012، 0. 0035-0. 004، 0. 0017-0. 003، 0. 0021-0. 0032، 2. 18-2. 97، 1. 45-1. 79 mg g-1 FW، respectively.

Industrial waste water usually has metal ions which can be harmful for human and other animals over the optimum level. In this study, removal of metal ions such as lead, copper and zinc from waste water using tree leaves were investigated aimingto introduce the cheap, effective and accessible adsorbents as compared to conventional adsorbents. For this aim 5 g of three leaves, namely Eucalyptus melanophlia and Eucalyptus camaldulensis from western Mazandaran province were selected, Then, 200 ml waste water containing metal ions such as lead, copper and zinc were prepared in specific concentrations and regulated at pH=5. The removal of metal ions from wastewater were tested in 30, 60, 90, 120 and 150 minutes. The result indicated significant differences between species and various removal time in 99% statistical confidence level; however Eucalyptus camaldulensis leaf had highest removal rate for zinc and copper as 68/86 and 35/32 percent, respectively. Eucalyptus melanophlia leaf had highest removal rate for lead as 33/67 percent. Also, the optimum connection time for removal of zinc from species, was 30 minutes. Also, the optimum connection time for removal of copper and lead was 120 minutes for Eucalyptus camaldulensis and the optimum connection time for removal of copper and lead for Eucalyptus melanophlia was 30 and 90 minutes. In general, for removal of zinc from waste water, the Leaves of all species has approximately equal efficiency in removing of metal ions, compared to the laboratory scale adsorbent (active carbon), which makes it more suitable regarding economical and environmental aspects. Also to remove metal ions, lead and copper leaf species compared with experimental adsorbent (activated carbon) is less effective.

Ohmic heating has an advantage over conventional indirect heating methods because heater (electrode) surfaces temperatures are comparatively lower as heat is generated within bulk fluid. Conventional ohmic heating under typical low frequency alternating current (50 or 60 Hz) could cause hydrogen and oxygen evolution due to electrolysis of water. This process could develop the electrodes decay or corrosion. Any decay or corrosion of electrodes shorten the life time and contaminate the food. The main objective of this study was to investigate the rate of the electrodes corrosion in the ohmic heating process. For this purpose the concentrations of Fe، Cr، Ni، Mn، and Mo from the stainless steel electrode migrated into ohmic and conventionally treated soup were measured. In this study migration of the major key metal ions from stainless steel measured by Atomic Absorption. The results showed that overall ohmic treatment yielded the same migration residues of all metal ions، compared to the conventional retorting with similar electrodes. Concentrations of all metal ions migrated into food samples after ohmic treatment were far lower than dietary exposure levels so that this technique can ensure the safety and quality of food supplies.

Industrial waste water usually has metal ions which could be dangerous over the optimum level for human and other animals. In this study the removal of metal ions such as lead, copper and zinc with tree leaves from waste water was investigated to introduce the cheap, effective and touchable adsorbents as compared with trade absorbent marks. For this reason 5gr of seven softwoods leaves such Beech, Oak, Alder, Mapel, Hornbeam, Walnut and Hazel were selected from the western part of Mazandaran providence, Then 200ml wastewater containing metal ions such as lead, copper and zinc were prepared in specific concentrations and then regulated in pH= 5. Then the removal of metal ions from wastewater were tested in 30, 60, 90, 120 and 150 minutes. The result indicated that there are significantl differences between species and various times in the removal of metal ions in 99% confident levels; however Beech leave had the highest removal rate of lead, copper and zinc as 51.89, 39.69 and 29.90 percent respectively. Also the optimum level of connection times for the removal of metal ions from hardwoods leaves are 90 minutes. The results revealed that beech leaves are more efficient in removing of metal ions, as compared with laboratory adsorbents (active carbon).