Local structures around metal atoms in Hi and Zn substituted 132-hydroxy-bacteriochlorophyll a (Ni-HOB, and Zn-HOB) with and without insertion into the accessory bacteriochlorophyll a (BChla) sites in Rhodobacter sphaeroides photosynthetic reaction centers (RC) are studied using X-ray absorption spectroscopy. The penta-coordination of Ni-HOB and Zn-HOB in the RC is similar to that of BChl a in ...

In the present investigation flocculation of dissolved Cu, Zn, Pb, Ni and Mn in a series of mixtures with salinities ranging from 1.5 to 9.5% during mixing of Talar river water with the Caspian Sea water was studied. The flocculation trend of Zn (87.22%) >Mn (45.31%) >Pb (39.09%) >Cu (36.58%)>Ni (12.70%) indicates that Cu, Zn, Pb and Mn have non-conservative behavior and Ni has relatively conse...

The focus of the review is on the specific aspects of Ni and Zn effects on growth morphology, Biochemical activity/responses, mineral nutrition and enzyme activity of plants. The quantity of Ni required for normal growth and development of plant is very low. Ni has been identified as a component of various enzymes in plants, various other biochemical, physiological and growth responses. The con...

17O NMR is used to probe the local influence of nonmagnetic Zn and magnetic Ni impurities in the superconducting state of optimally doped high TC YBa2Cu3O7. Zn and Ni induce a staggered paramagnetic polarization, similar to that evidenced above TC, with a typical extension xi=3 cell units for Zn and xi>or=3 for Ni. In addition, Zn is observed to induce a local density of states near the Fermi e...

The present work is concerned with sulfidation of Cu, Zn and Ni containing plating wastewater with CaS. The sulfidation experiments were carried out at a room temperature by adding solid CaS to simulated metal solution containing either single-metal of Ni, Zn and Cu, or Ni-Zn-Cu mixture. At first, the experiments were conducted without pH adjustment and it was found that the complete sulfidatio...

A preconcentration method was developed for the determination of trace amounts of Co, Ni, Cd and Zn by atomic absorption spectrometry. The method is based on the retention of the metal cations by naphthalene–2,4,6-trimorpholino-1,3,5-triazin adsorbent in a column. The adsorbed metals were then eluted from the column with hydrochloric acid and the Co, Ni, Cd and Zn were determined by flame atomi...

In certain areas of Varanasi city, waste water from Dinapur sewage treatment plant is used for irrigating vegetable plots. We quantified the concentrations of heavy metals, viz. Cd, Cr, Cu, Ni, Pb and Zn in soil, vegetables and the waste water used for irrigation. The waste water used for irrigation had the highest concentration of Zn followed by Pb, Cr, Ni, Cu and Cd. Continuous application of...

Freshwater quality criteria for iron (Fe), lead (Pb), nickel (Ni), and zinc (Zn) were developed with particular reference to aquatic biota in Malaysia, and based on USEPA's guidelines. Acute toxicity tests were performed on eight different freshwater domestic species in Malaysia which were Macrobrachium lanchesteri (prawn), two fish: Poecilia reticulata and Rasbora sumatrana, Melanoides tubercu...

the study aimed to come up with a list of specific macroalgae species, which could be used to biomonitor specific metal elements in the coastal waters of east africa. water extraction, edta, aqua regia extraction and optimized bcr 3-step sequential extracts were used to mimic bioavailable metals under various environmental conditions. the results indicated that ulva lactuca could be used as a b...

abstruct anzali wetland in north of guilan provience is an international important wetland that is recorded in ramsar convension. pollution is one of the major problems facing this wetland. in order to investigate the pollution situation, sediment core samples were taken in 7 stations in 4 districts within the wetland, namely abkenar, siakishom, hendekhale and shijan). elements were determined ...