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Organic electronics is currently experiencing a surge of activities worldwide prompted in part by recent advances in achieving high electronic mobility, light emission over a broad range of frequencies, demonstration of spin valve operation with giant magneto-resistance and other effects. Despite these encouraging promises, there are many roadblocks that hinder a broader proliferation of "plastic electronics" in contemporary technology. Such devices involve charge transport as a main process in their operation processes, and therefore, require high-performance charge-transporting materials. The charge-carrier mobility is the major determining factor for the speed of electronic devices. Arguably, the most significant of them is the challenge to achieve a comprehensive understanding of the fundamentals of charge injection and charge transport in organics. In spite of its simple definition, because of the difficulty of measuring velocity, accurate determination of the mobility of the carriers is not easy and indirect ways are used, each with its own advantages and disadvantages. The article discusses important mobility measurement techniques employed for organic optoelectronic devices.

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The paper reports that the mechanoluminescence (ML) is not an inherent property of only the non-centrosymmetric crystals. The ML may appear in number of centrosymmetric crystals due to variety of processes. The ML of 82 centrosymmetric crystals are reported and different models are proposed for the ML excitation. The models proposed are: space charge electrificaiton model, triboelectrification model, phase transformation model, gas adsorption model, chemical reaction model, thermal population model, molecular deformation model, cleavage electrification model, defective piezoelectric phase model, dislocation defect stripping model, dislocation unpinning model, dislocation annihilation model, charged dislocation model and incandecent light emission model. It is shown that on the basis of the proposed model, intense mechanoluminescent materials with desired nature and characteristics may be prepared.

II-VI semiconductor nanoparticles have recently attracted a lot of attention due to the possibility of their application in various devices. In the present study, chemical method has been used in synthesis of CdS nanoparticles and thiophenol was used as capping agent. X-ray diffraction studies of both samples were done. The dc conductivity of CdS increases at a lower rate or is approximately constant upto 500K and thereafter the conductivity increases at a rapid rate. Beyond T c it is seen that the portion of the σ dc versus 1000/T is almost a straight line showing an Arrehenious behaviour. The dielectric constant of nanoparticles of CdS is found to be larger than the corresponding values of CdS crystals. It is clearly observed that at lower wavelengths nanocrystalline samples show a blue-shift. The three peaks of sample (S2), A, Band C can be ascribed to the transition from Cd-O complex donor formed by adsorbed oxygen to the valance band, Cdexcess acceptor and the surface states, respectively.

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Project managers today rely on scheduling tools based on project network techniques like Critical Path Method (CPM) to determine the overall project duration and the activities float time. Such data provide important information about the degree of flexibility with respect to the project schedule that leads to greater efficiency in planning and control of projects. The traditional representation of CPM, however, is based on two unrealistic assumptions: that the project deadline is not restricted and that resources are unlimited. In most of the construction projects the deadline and resource limits are practical constraints that need to be satisfied simultaneously. While the available literatures describe several techniques to resolve the Time Cost Trade off (TCT) and Constrained Resource Scheduling (CRS) individually, little effort has been devoted to consider them simultaneously because of the higher modeling complexity involved. No commercial software includes any TCT heuristic to help meet deadline, let alone any procedure to resolve both deadline and resource constraints. In practice on the other hand there is a need to formulate a method that simultaneously resolves to meet out the specified duration and resource constraints. This paper therefore introduces a two-step procedure where first the TCT is applied using Microsoft excel software to meet the project deadline assuming unlimited resources. The various feasible schedules obtained in the first step are then explored by applying CRS using Microsoft Project Software (MSP) to arrive at the desired project schedule meeting the deadline with available resources. The proposed approach was experimented on several case studies that proved its usefulness. The intertwined approach using simple and popular Microsoft office tools (Excel and MSP) is logical, fast and provides a set of feasible project schedule meeting the deadline and that do not violate resource limits.