in this paper metal-assisted chemical etching has been applied to pattern porous silicon regions and silicon nanohole arrays in submicron period simply by using positive photoresist as a mask layer. in order to define silicon nanostructures, metal-assisted chemical etching (mace) was carried out with silver catalyst. provided solution (or materiel) in combination with laser interference lithogr...

hydraulic fracturing (hf), as a stimulation technique in petroleum engineering, has made possible the oil production from reservoirs with very low permeability. the combination of horizontal drilling and multiple hf with various perforation angles has been widely used to stimulate oil reservoirs for economical productions. despite the wide use of hf, there are still ambiguous aspects that requi...

background: no uniform consensus exists to decide type of fixation for arthroscopic anterior cruciate ligament reconstruction. hypothsis: there is similar functional outcome after rigid fix compared to other methods of fixation which has been published. study design: retrospective observational study. methods: a total of 50 patients underwent arthroscopic anterior cruciate ligament reconstructi...

abstract field experiment was conducted to evaluate the effects of sowing date, crop density, and weed interference on yield and yield components of chickpea in lorestan province during 2005-06. the experimental was a randomized complete block design by factorial arrangement with 4 replications. the experiment had 3 factors: sowing date at 2 levels (autumn, and winter), crop density at 3 levels...