crop residues management is one of the most important factors to sustain agro-ecosystems. application of plant residues as organic fertilizers has functional role on the amount of soil elements, their availability for crops and finally yield obtained. in order to investigate the effect of different crop residues and their management on providing wheat potassium requirement, a four-replicated fi...

The polyhedral complex [Cu(4)L(H(2)O)(4)]solv (NOTT-140) shows a 4,8-connected structure of rare scu topology comprising octahedral and cuboctahedral cages; desolvated NOTT-140a shows a total CO(2) uptake of 314.6 cm(3) (STP) cm(-3) at 20 bar, 293 K, and a total H(2) uptake of 6.0 wt% at 20 bar, 77 K.

This work studied simultaneous removal of ammonium and potassium ions by ion exchange with the natural zeolite clinoptilolite. Synthetic and real RO permeate used in experiments contained approximately 250 mg NH4/L and 200 mg K/L. The real RO permeate was obtained from membrane treatment of anaerobically digested cattle manure effluents. Batch experiments were conducted to determine ammonium an...

Potassium (K(+)) is an essential nutrient required by plants in large quantities, but changes in soil concentrations may limit K(+) acquisition by roots. It is not known how plant root cells sense or signal the changes that occur after the onset of K(+) deficiency. Changes in the kinetics of Rb(+) uptake in Arabidopsis roots occur within 6 h after K(+) deprivation. Reactive oxygen species (ROS)...

PURPOSE Cultured rabbit nonpigmented ciliary epithelium (NPE) transports ascorbic acid (ASC) inward through a sodium-dependent mechanism. This study was conducted to test whether Na-K transport is activated to export the additional sodium, which enters the cell in cotransport with ASC. METHODS Studies were conducted using a cell line derived from rabbit NPE. ASC uptake was measured using [14C...

Polyamine uptake, the kinetics of this uptake, and the competition among polyamines and between polyamines and inorganic cations were studied in petals of Saintpaulia ionantha Wendl. Uptake experiments using (14)C-labeled polyamines were carried out on single petals, at room temperaure (20 degrees C) and in the light. The results show that putrescine, spermidine, and spermine uptake was depende...

Tetraphenyladamantane-based porous poly(Schiff base)s with BET surface area (>1000 m(2) g(-1)), CO2 uptake (15 wt%, 273 K/1 bar) and H2 uptake (1.26 wt%, 77 K/1 bar) were synthesized. The structure-directing effect of isomers of phenyl diamines on building porous architecture was investigated.

A porous metal-organic framework with high surface area was designedly synthesized, in which polyhedral cages and one-dimensional channels coexist. It shows a total gravimetric H2 uptake of 11.35 wt% at 77 K and 90 bar and a total CH4 uptake of 305.07 cm(3) g(-1) at 298 K and 35 bar.

In hepatocyte cultures, insulin stimulates cellular accumulation of K+, partly (approximately 20%) by net replacement of cell Na+, but largely (approximately 80%) by increasing the cell K++Na+ content, with a consequent increase in cell volume. An increase in cation content occurred within 5 min of exposure to insulin and was not secondary to metabolic changes. Insulin also increased the cation...

Prolonged exhaustive submaximal exercise in humans induces marked metabolic changes, but little is known about effects on muscle Na+-K+-ATPase activity and sarcoplasmic reticulum Ca2+ regulation. We therefore investigated whether these processes were impaired during cycling exercise at 74.3 +/- 1.2% maximal O2 uptake (mean +/- SE) continued until fatigue in eight healthy subjects (maximal O2 up...