Plant cell cultivations are being considered as an alternative to agricultural processes for producing valuable phytochemicals. Since many of these products (secondary metabolites) are obtained by direct extraction from plants grown in natural habitat, several factors can alter their yield. The use of plant cell cultures has overcome several inconveniences for the production of these secondary metabolites. Organized cultures, and especially root cultures, can make a significant contribution in the production of secondary metabolites. Most of the research efforts that use differentiated cultures instead of cell suspension cultures have focused on transformed (hairy) roots. Agrobacterium rhizogenes causes hairy root disease in plants. The neoplastic (cancerous) roots produced by A. rhizogenes infection are characterized by high growth rate, genetic stability and growth in hormone free media. These genetically transformed root cultures can produce levels of secondary metabolites comparable to that of intact plants. Hairy root cultures offer promise for high production and productivity of valuable secondary metabolites (used as pharmaceuticals, pigments and flavors) in many plants. The main constraint for commercial exploitation of hairy root cultivations is the development and scaling up of appropriate reactor vessels (bioreactors) that permit the growth of interconnected tissues normally unevenly distributed throughout the vessel. Emphasis has focused on designing appropriate bioreactors suitable to culture the delicate and sensitive plant hairy roots. Recent reactors used for mass production of hairy roots can roughly be divided as liquid-phase, gas-phase, or hybrid reactors. The present review highlights the nature, applications, perspectives and scale up of hairy root cultures for the production of valuable secondary metabolites.

Chemical effects of contact glow discharge electrolysis (CGDE) at an electrode where a plasma is sustained by dc glow discharges between the electrode and the surrounding electrolyte, are remarkably nonfaradaic. A critical analysis of the chemical results of anodic CGDE at varying voltages, currents, power supplies, and pHs clearly shows that nonfaradaic yields originate in two separate reaction zones: the plasma around the anode and the liquid anolyte near the plasma-anolyte interface. The yields from the former zone appear from 250 V onward (the beginning of the onset of partial glow discharge) and vary linearly with the power dissipated in the glow discharge. The yields from the latter zone appear from 410 V onward (the beginning of the full glow discharge) and are independent of the power dissipated in the glow discharge. The relative contribution of the two zones to the total nonfaradaic yields is dependent on the voltage applied: the plasma zone having a share of 100% up to 400 V, followed by 20% up to 450 \) and thereafter rising steadily to 57% at 500 V. ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.64.11.153 Downloaded on 2014-12-02 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.64.11.153 Downloaded on 2014-12-02 to IP

This paper deals with the microstructural and mechanical properties of a transformation-induced plasticity-aided martensitic (TM) steel that is expected to serve as an advanced structural steel for automotive applications. The microstructure consisted of a wide lath-martensitestructured matrix and a mixture of narrow lath-martensite and metastable retained austenite of 2-5 vol% (MA-like phase). When 1%Cr and 1%Cr-0.2%Mo were added into 0.2%C-1.5%Si-1.5%Mn steel to enhance its hardenability, the resultant TM steels achieved a superior cold formability, toughness, fatigue strength, and delayed fracture strength as compared to conventional structural steel such as SCM420. These enhanced mechanical properties were found to be mainly caused by (1) plastic relaxation of the stress concentration, which resulted from expansion strain on the strain-induced transformation of the metastable retained austenite, and (2) the presence of a large quantity of a finely dispersed MA-like phase, which suppressed crack initiation or void formation and subsequent void coalescence.

Abstract. We investigated the application of one-dimensional fluid model in modeling of electron transport in carbon nanotubes and equivalent circuits for interconnections and compared the performances with the currently used copper interconnects in very-large-scale integration (VLSI) circuits. In this model, electron transport in carbon nanotubes is regarded as quasi one-dimensional fluid with strong electron-electron interaction. Verilog-AMS in Cadence/Spectre was used in simulation studies. Carbon nanotubes of the types single-walled, multiwalled and bundles were considered for ballistic transport region, local and global interconnections. Study of the S-parameters showed higher transmission efficiency and lower reflection losses. Theoretical modeling and computer-aided simulation studies through a complementary CNT-FET inverter pair, interconnected through a wire, exhibited reduced delays and power dissipations for carbon nanotube interconnects in comparison to copper interconnects in 22 nm and lower technology nodes. The performance of CNT interconnects was shown to be further improved with increase in number of metallic carbon nanotubes. Our study suggests the replacement of copper interconnect with the multiwalled and bundles of single-walled carbon nanotubes for the sub-nanometer CMOS technologies.

No abstract