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[en] The throwing power of commercial acid zinc plating solutions is examined and the major factors that affect throwing power are discussed. The effect of the concentration of bath constituents on throwing power is shown in terms of conductivity and cathode efficiency. As the concentration of zinc chloride is decreased, the conductivity increases until a maximum value is reached and, upon further decrease, the value decreases very slowly. The cathode efficiency decreases with the decrease of concentration. Finally, the throwing power increases with the decrease of concentration rather slowly at first and then rapidly later, forming the plateau portion
[en] A theoretical phase diagram of [N(CD3)4]2ZnCl4 crystal is constructed in the plane of two thermodynamic-potential coefficients. The orientation of the temperature (T) and pressure (P) axes is chosen in the diagram. The first diagram is used as a basis to construct the second theoretical T-P phase diagram, expanded to the region of weak negative pressures for nondeuterated [N(CH3)4]2ZnCl4 crystal. It is suggested that this region can be observed for deuterated [N(CD3)4]2ZnCl4 crystal
[en] The reactions of 1H-1,2,4-triazole (Htr) with MX_2 (ZnCl_2 for 1: CdBr_2 for 2) resulted in two coordination polymers, [Zn(tr)Cl]_n and [Cd(Htr)_2Br_2]_n. The structural analyses indicate that 1 and 2 feature a 2D layer and 1D triple chain, respectively. In 1, neighbouring Zn atoms are connected by μ_3-1 _κN: 2 __κN: 4 __κN-tr"- anionic ligand into 6- and 16-membered rings, further grow into a 2D sheet. Cd atoms in 2 are bonded by two μ_2-Br"- bridges and neutral μ_2-1 __κN: 2 __κN-Htr to form a 1D triple chain. The fluorescent characterizations of 1, 2 and the free Htr ligand feature similar emission peaks at 444, 446 and 423 nm respectively, which can be assigned to intra-ligand π-π * transition of (H)tr. The energy gaps of 5.90 eV for 1, 5.16 eV for 2, and 5.93 eV for HTR suggest that the compounds behave as insulators
[en] Topological versus chemical ordering in disordered binary systems is investigated by using the Bhatia-Thornton formalism. The moments of the partial pair-distribution functions are considered and are related to relevant thermodynamic and other properties of the system. The results are illustrated by using the measured partial-pair distribution functions for the network forming glasses ZnCl2 and GeSe2
[en] The feasibility of cleaning three Turkish lignites (Beypazari, Goelbasi and Kangal lignites) by the dense medium separation or the froth flotation method has been investigated. Solutions of zinc chloride (ZnCl2) with specific gravities ranging from 1.1 to 1.75 have been used as the dense medium. In the case of froth flotation, methyl isobutyl carbinol (MIBC), diethyl isohexanol (DEH) and sodium dodesyl sulphonate (SDS) were used as the frother and kerosene was used as the collector. In both methods, each lignite sample was separated into two sub-fractions: the lignite rich part and the mineral matter rich part. The results indicate that the effectiveness of the methods in ash and sulphur removal is appreciably different for the different lignites. An effective pyritic sulphur removal (over 90%) was obtained for Beypazari or Goelbasi lignites by the dense medium separation. The effectiveness of the froth flotation was relatively different depending on both the lignite and frother type. The recovery is generally low and changes considerably depending on the frother type and particle size
[en] In the case of a conventional zinc bromide electrolyte solution using zinc chloride as additive, an undesirable reaction occurs. In this reaction, complex anions form between zinc and the chloride ions during charging and discharging. To overcome this problem, this paper describes an excellent electrolyte solution using zinc per-chlorate as the additive, resulting in a highly stable and reversible reaction in zinc-bromine flow cells. To show the effectiveness of the proposed solution, electrochemical analyses are carried out using cyclic voltammetry, a miniature zinc-bromine flow cell, and scanning electron microscopy. The solution is then compared with the conventional electrolyte solution using zinc chloride as the supporting material. Experimental results show that use of the zinc perchlorate additive increases the rate of zinc dissolution by improving the reaction rate of bromine in the catholyte half-cell. Consequently, this arrangement allows a highly stable operation for improving the current efficiency of zinc-bromine flow batteries.
[en] Synthetic application of Silica–ZnCl2, as an efficient and eco-friendly catalyst for the synthesis of a small library of dihydropyrimidinones is described in this report. The reaction involves a one pot, multicomponent reaction of β-oxodithiocarboxylates, aldehydes, and urea under solvent-free conditions. The experimental procedure is simple, environmental benign, tolerated with many functional groups, and results in good to excellent yield of the products
[en] Background: Administration of quinolone therapy is controversial during growing age as stated by earlier authors. The flouroquinolones are currently not indicated for young children because of arthropathy and adverse effect as new born shown by studies. However the effects of ciprofloxacin and ZnCl/sub 2/ on prenatal conceptus have remained undocumented. The present study was designed to compare the effects on conceptus after maternal ingestion of ciprofloxacin and ZnCl/sub 2/ using Wastar albino rats. Methods: Ciprofloxacin and ZnCl/sub 2/ was administrated to pregnant female albino rats. Ciprofloxacin with a dose of 20 mg/Kg bodyweight and ZnCl/sub 2/ 120 micro g/100 gm bodyweight two times therapeutic dose for 10 days (from day 8-18 of pregnancy). Each animal was weighted on day 1, day 8 and day 18 of pregnancy. Abortion resulted on day 18th of pregnancy. Each group of pregnant animals were sacrificed on day 18 of gestation by over dose of either anaesthesia, abdomen opened, uterus and both cornua containing conceptus identified, removed, there weight recorded, crown rump length was measured and was compared with similar value of control animals. The results were statistically analysed to find out the significance. Results: The ciprofloxacin induces a mordanting effect as obviated by increased basophilia. Our study reveals that ciprofloxacin administered in maternal, decreased maternal body weight to 38.4+-0.9 gm. However simultaneous ZnCl/sub 2/ maintained the body weight to 41.4+-0.7 gm, while ZnCl/sub 2/ increased the body weight to 46.5+-2.25 gm. The body weight and Crown Rump length (CR Length) in conceptus decreased by 4.52+-0.10 gm and 3.06+-0.09 Cm respectively. That ciprofloxacin and ZnCl/sub 2/ administration maintained the body weight and CR length by 5.46+-0.09 gm and 3.79+-0.13 Cm respectively. That ZnCl/sub 2/ administration increased the body weight and CR length by 6.71+-0.05 gm and 4.15+-0.08 Cm respectively. Conclusion: Prenatal administration of Ciprofloxacin caused reduction in growth rate and CR length, and ZnCl/sub 2/ maintained body weight and CR length and growth of the rat conceptus. (author)
[en] A metal hydro-borate Zn(BH_4)_2 was prepared by milling ZnCl_2 and NaBH_4 in a planetary ball mill in an Ar atmosphere. This sample contained NaCl. 95 wt% MgH_2-2.5 wt% Zn(BH_4)_2-2.5 wt% Ni samples [named MgH_2-2.5Zn(BH_4)_2-2.5Ni] were then prepared by milling in a planetary ball mill in a hydrogen atmosphere. The hydrogen absorption and release properties of the prepared samples were investigated. In particular, variations in the initial hydriding and dehydriding rates with temperature were examined. MgH_2-2.5Zn(BH_4)_2-2.5Ni dehydrided at the fourth cycle contained Mg, MgO, and small amounts of β-MgH2 and Mg2Ni. The sample after hydriding-dehydriding cycling had a slightly smaller average particle size and a larger BET specific surface area than the sample after milling. Increasing the temperature from 573 K to 623 K led to a decrease in the initial hydriding rate. The initial dehydriding rate increased as the temperature increased from 573 K to 643 K. At 573 K under 12 bar H_2, the sample absorbed 3.85 wt% H for 2.5 min, 4.60 wt% H for 5 min, 4.64 wt% H for 10 min, and 4.80 wt% H for 60 min. The MgH_2-2.5Zn(BH_4)_2-2.5Ni had an effective hydrogen storage capacity (the quantity of hydrogen absorbed for 60 min) of near 5 wt% (4.96 wt% at 593 K).
[en] A new formulation of a freeze-dried kit for the labeling of a novel recombinant Annexin V molecules (with a single cysteine residue at its C-terminal, Cys-Annexin V) with technetium-99m has been developed. Effects of the amount range of Cys-Annexin V, stannous chloride, glucoheptonate and disodium edetate on the radiolabeling yield were studied in details. The stabilities of 99mTc-Cys-Annexin V and freeze-dried kits were performed, respectively. In vitro cell uptake studies showed the binding of 99mTc-Cys-Annexin V was specific on testing with apoptotic H446 cells. Therefore, 99mTc-Cys-Annexin V is a potential apoptosis imaging agent and further study is needed. (author)