semiconducting carbon nanofibers (cnf) are prepared from three different sources, i.e., acetylene, ethanol, and cotton by the chemical vapor deposition (cvd) process. these fibers are having rich elastic, engineering and conductivity properties. fresh self-compacting concrete (scc) flows into place and around obstructions under its own weight to fill the formwork completely and self-compact, wi...

one of the most effective tools for decline cost and time, quality improvement and consequently project performance enhancement especially in construction projects, is value engineering. there are linguistic judgments in many cases of value engineering studies in construction projects such as interior design, mechanical installations design, and etc. therefore multiple attribute decision-making...

upgrading recycled fiber properties has been a constant concern in pulp and paper industry. in this respect many researches has been applied. the present paper has been considered the effect of amylase enzyme in pulping stage of old corrugated container (occ). also, pre-soaking of occ (first step of pre-soaking for 6 hours in 3% consistency in different ph(s) and second step of pre-soaking at 6...

The design and performance of land grid array (LGA) sockets are discussed with respect to high-performance server applications. Motivations for the use of this technology are presented, and the specific challenges associated with its application are discussed from a mechanical perspective. A variety of mechanical performance considerations are identified for LGA socket technologies, and a detai...

Problem statement: Abrasive is one of key influencing factors on the polished surface quality in Chemical Mechanical Polishing (CMP). Solid abrasives in CMP slurries are easy to cause polishing scratches. It is well known that reducing the hardness of abrasives would improve the polished surface quality. Therefore, the change in structure or shape of the abrasives means a change in polished sur...

This paper presents two recent developments in deep silicon etching for MEMS applications using an Alcatel ICP deep dry etching system. In the first part of the paper, a new technique for doubling the state-of-the-art Trench Aspect Ratio from 30 to 60 is introduced. Results are presented showing submicron 0.4 μm wide trenches etched to a depth of 24 μm. In the second part, a new method for dry ...

polyvinylidene fluoride/polyvinylpyrrolidone (pvdf/pvp) hollow fiber membranes were fabricated by dry-jet wet-spinning process. the correlated effects of the air gap length and pvp concentration ((1) the air gap length effect at the low and high pvp concentration in the dope solutions, as well as (2) the effect of the pvp concentration at the same air gap length) on the cross-section structure ...

MEMS (microelectromechanical system) fabrication can be organized as three sub-processes, that is, the front-end process, the wafer cap process, and the back-end process. The coordination between the releases of raw wafers to the two parallel sub-processes, the front-end process, and the wafer cap process, is always an important issue. Previous research work has developed synchronization rules ...

since co2 pneumoperitoneum is the dominant method of laparoscopic exposure due to facility and good view, its physiologic effects are most relevant to the surgeons. co2 pneumoperitoneum may affects hemodynamics by increased intra-abdominal pressure (iap) and the physiologic effects of absorbed co2. the adverse effects of both mechanisms relate directly to the duration of the pneumoperitoneum an...

reactive powder concrete (rpc) is an ultra high performance concrete which has superior mechanical and physical properties. the rpc is composed of cement and very fine powders such as crushed quartz (100–600 μm) and silica fume with very low water/binder ratio (w/b) (less than 0.20) and super plasticizer (sp). the rpc has a very high compressive and tensile strength with better durability prope...