The preparation of the new ligand 1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane, (-N(Me)-(CH2)2-)4 (= L), and the complexes [NiL] (ClO4)2, [NiL(OCHNMe2)] (ClO4)2, [NiLN3] ClO4, [CuL] (ClO4)2, and [NiY] (ClO4)2, where Y = (-N(Me)(CH2)2N(Me)(CH2)3-)2, 1,4,8,11-tetra-methyl-1,4,8,11-tetraazacyclotetradecane, are described. The magnetic moments of the nickel((11) species are reported, and the labile low-spin/high spin equilibria characterizing the [NiLI2+ and [NiY]2+ systems over a range of temperatures and ionic strengths in aqueous solution are discussed. The spectrophotometric titration of the aqua ligands in [NiLH2O]2+, [CuLH2O]2+, and [NiYH2O]2+ against sodium hydroxide yields pKa values of 10.2 � 0.2, 12.0 � 0.3 and 10.7 � 0.2, respectively, and a study, using Job's method of continuous variations, of the formation of azide species shows [NiLN3]+ and [NiYN3]+ to be formed predominantly in aqueous solution.

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A common voltage-controlled oscillator (VCO) architecture used in the phase locked loop (PLL) is the ring oscillator (RO). RO consist of number of inverters cascaded together as the input of the first stage connected to the output of the last stage. It is important to design the RO to be work at desired frequency depend on application with low power consumption. This paper presents a review the performance evaluation of different delay cell topologies the implemented in the ring oscillator. The various topologies analyzed includes current starved delay cell, differential delay cell and current follower cell. Performance evaluation includes frequency range, frequency stability, phase noise and power consumption had been reviewed and comparison of different topologies has been discussed. It is observed that starved current delay cell have lower power consumption and the different of the frequency range is small as compared to other type of delay cell.

Negative Bias Temperature Instability (NBTI) has become one of the critical reliability concerns as scaling down CMOS technology especially on the pMOSFET device. A simulation study had been conducted on 32 nm conventional pMOSFET using the technology CAD (TCAD) Sentaurus Synopsys simulator tool. In this paper, the effects of the gate oxide thickness together with drain bias variations on the NBTI are studied. The effect on the device parameters such as interface traps concentration (N it ), threshold voltage (V th ) and drain current (I d ) degradation had been investigated and explained in detail.

<span>This paper describes the design and development of a measuring tool using a mobile robot. At present, contractors are measuring distances using measuring tape which has few limitations. This includes using of another manpower or a marking flag. The Robot Measuring System is designed to measure distances at multiple conditions such as smooth and rough surface. An optical quadrature encoder is used as a sensor to measure the distances while a program is installed in Arduino Uno for reading and data collection. Graphical User Interface (GUI) was created using Android software so that the movement of the robot can be controlled using a smartphone within a Bluetooth range. An experiment was conducted to test the reliability in terms of accuracy and precision. The best accuracy and precision were obtained when the robot speed is at 90 cm/s on the plain tiles, 80 cm/s on the tar road and 90 cm/s on the grass surface. The robot speed needs to be adjusted accordingly based on the surfaces in order to get an accurate result. <br /> This paper proved that the robot measuring system was successfully designed, implemented and analyzed.</span>

This paper describes the design and development of a shoe dryer using a microcontroller. Nowadays, people often travel and sometimes in rainy day, they need to dry their shoe in a very short time anywhere. However, very rare of places including shopping mall and hotel provide a shoe dryer. The shoe dryer is designed to help people who are in hurry to dry their shoe on the go. A temperature sensor is used to measure the temperature inside the shoe dryer, while a program is uploaded in the microcontroller for reading and data collection. The programming includes the activation of shoe dryer with the GSM module, thus it can be controlled using a mobile phone. An experiment was conducted to test the performance of the shoe dryer. The optimum performance was obtained when the temperature is set at 36°C, and timer at 60 seconds with normal room temperature. The temperature and timer need to be adjusted accordingly based on the shoe condition in order to get very satisfying results. This paper proved that the shoe dryer was successfully designed, implemented and analyzed.