mulches often use for weed control, hold soil moisture, decrease soil temperature, soil fertility, soil conservation, soil against rain and soil quality in organic farming. a field experiment was conducted to evaluate the effect of different wheat residue and sunflower densities on sunflower growth and yield during 2007 growing season at the research field of birjand university. the experimenta...

crop residue is a non-chemical method of weed control in agricultural sustainable systems. this research was conducted at the alarogh site of ardabilto evaluate the effect of integrated use of mulch and herbicide on weed emergence and growth in potato in 2007. treatments were four levels herbicide including: (1) paraquat [n,n'-dimethyl-4,4'-bipyridinium dichloride] herbicide as pre-pl...

representation of the dimeric units of K2[Zr(SO4)3]. 2H20. Examination of this structure shows that breaking and remaking one oxygen bridge in each dimeric ring of K2[Zr(SO4)3.2H20 would result in the formation of infinite-Zr-O-SO -Zr-chains similar to those found in Na2[Zr(SO4)3]. 3H20 [Fig. 3(c)] and we see that in these two compounds we have an extension of the structural arrangements alread...

The pharmacokinetics and tissue distribution of the monoclonal antibody radioconjugate 111In-diethylenetriaminepentaacetic acid-KC-4G3, which is directed against a high molecular weight mucin(s) antigen expressed on the human milk fat globule and many epithelial cell membranes, were examined in BALB/c nude mice with and without xenografts of the human tumor lines ZR-75 (mammary adenocarcinoma, ...

It is well known that plasma levels of dehydroepiandrosterone (DHEA), a steroid hormone secreted by zona reticularis (ZR) of the adrenal cortex, reach the maximal values in the third decade of life and then gradually decline with age. Moreover, the DHEA deficiency is probably responsible for several functional disturbances connected with aging. It was also found that ZR reaches its definitive v...

Recently, we have identified the Al-alkenyl species iBuAl(oct-7-en-1-yl)2 (Al-1) as a promising long-chain branching (LCB) promoter in ethylene polymerization catalyzed by rac-{EBTHI}ZrCl2-based systems, proposing incorporation of its alkenyl moiety into growing polyethylene (PE) chain crucial step for LCB formation. The success process was attributed to high copolymerization ability selected c...

chemistry of anion recognition is now being uncovered and producing a variety of practical applications, including separation and sensing. 1–3 The use of Lewis acid-base interactions is a promising approach in this respect. We previously found that zirconium(IV) could be immobilized on a chelating polymer, having an iminodiacetate (IDA) group (–LH2), as a 1:1 complex of [(–L)Zr(OH)2]. 4,5 This ...

Binuclear redox sites consisting of a Zr oxo-bridged to a Cu(I) center have been obtained on the pore surface of MCM-41 silicate sieve by a stepwise grafting procedure, along with isolated metal centers. The bimetallic site features a Zr(IV)-O-Cu(I) to Zr(III)-O-Cu(II) metal-to-metal charge-transfer (MMCT) absorption extending from the UV region to about 500 nm. The Zr-O-Cu linkage is revealed ...

An effort has been made to improve the coercivity of nanocomposite Nd10Fe82C6B2 alloys, using small amounts (up to 1 at%) of Cr, Ti, Nb, Zr, and Ga. X-ray studies revealed that the amount of –Fe phase in both as-spun and annealed ribbons was significantly reduced for Nb and Zr substitutions, but increased for all the other substitutions. From the magnetic properties point of view, Zr (1 at%) wa...

The TiCp/Cu master alloy was prepared via thermal explosion reaction. Afterwards, the nano-sized TiCp/Cu master alloy was dispersed by electromagnetic stirring casting into the melting Cu-Cr-Zr alloys to fabricate the nano-sized TiCp-reinforced Cu-Cr-Zr composites. Results show that nano-sized TiCp can effectively refine the grain size of Cu-Cr-Zr alloys. The morphologies of grain in Cu-Cr-Zr c...