Cobalt is a nutrient to phytoplankton, but knowledge about its biogeochemical cycling is limited, especially in the Pacific Ocean. Here, we report sections of dissolved cobalt and labile dissolved cobalt from the US GEOTRACES GP16 transect in the South Pacific. The cobalt distribution is closely tied to the extent and intensity of the oxygen minimum zone in the eastern South Pacific with highes...

The effect of cobalt precursor on the structure of Co supported multi-walled carbon nanotubes (MWCNTs) were studied by using X-ray photoelectron spectroscopy (XPS). MWCNTs were treated with a mixture of nitric and sulfuric acids and decorated with cobalt and/or cobalt oxides via aqueous impregnation solutions of cobalt nitrate or cobalt acetate followed by reduction in hydrogen. XPS was mainly ...

Quality control and validity check of the solid-phase spectrophotometric procedure (Me-SPS) for determination of heavy metals important in pharmaceutical practice: zinc (Zn-SPS), lead (Pb-SPS), and cobalt (Co-SPS) were performed using a very simple and informative prevalidation concept. Further, metrological characteristics of the Me-SPS procedure together with the diagnosis of particular preva...

The blood-red plutonocene complex Pu(1,3-COT'')(1,4-COT'') (4; COT''=η8 -bis(trimethylsilyl)cyclooctatetraenyl) has been synthesized by oxidation of the anionic sandwich complex Li[Pu(1,4-COT'')2 ] (3) with anhydrous cobalt(II) chloride. The first crystal structure determination of an organoplutonium(IV) complex revealed an asymmetric sandwich structure for 4 where one COT'' ring is 1,3-substit...

Oxygenation Catalyst, Cobalt Schiff-Base Complex, Crystal Structure, Electrochemistry N,N'-Bis(salicylidene)ethylenediaminatocobalt(III) hydroxide is treated with chloroform in methanol to yield the corresponding chloride in pure, crystalline form. Results of the crystal structure determination compare well with those in earlier reports of dimeric [Co(salen)Cl]2 units and incorporated CHC13 mol...

The detector, a multi-channel photometric detector, described in this paper was developed using multi-wavelength LEDs (light emitting diode) and phototransistors for absorbance measurement controlled by an Intel 8031 8-bit single chip microcomputer. Up to four flow cells can be attached to the detector. The LEDs and phototransistors are both inexpensive, and reliable. The results given by the d...

The cobalt complex [{K(18-crown-6)}2(C5H5)][Co(C8H12)2]·(THF)2 (3) has been synthesized and characterized by X-ray single-crystal structure determination. The crystal structure of Co(C8H12)(C8H13) (2) has been reinvestigated and compared with the structure of 3. The 1,5-cyclooctadiene (C8H12) and C8H13 ligands are coordinated in an η4 and η3 fashion, respectively. The cyclopentadienyl anion in ...

Native zinc/cobalt-containing ATP sulfurylase (ATPS; EC 2.7.7.4; MgATP:sulfate adenylyltransferase) from Desulfovibrio desulfuricans ATCC 27774 was purified to homogeneity and crystallized. The orthorhombic crystals diffracted to beyond 2.5 A resolution and the X-ray data collected should allow the determination of the structure of the zinc-bound form of this ATPS. Although previous biochemical...

the potential of carbon nanotubes (cnt) supported cobalt catalysts for fischer-tropsch (ft) reaction is shown. using the wet impregnation method cobalt on carbon nanotubes catalysts were prepared with cobalt loading varying from 15 to 45 wt. %. the catalysts are characterized by different methods including: bet physisorption, x-ray diffraction, hydrogen chemisorption, and temperature-programmed...

Uranium and some other trace elements were determined in the size-separated airborne dust collected in Tsukuba with an Andersen-type high-volume cascade impactor. The fission track method and the instrumental neutron activation method were applied to the determination of uranium and other elements, respectively. Selenium, antimony, arsenic and zinc were found to be rich in particulates of small...