1.0 Abstract

SCADA is a system based on blocks of electronic and communication evolutions, it stands for Supervisory control and data acquisition, it comprises of plants where sensors and actuators are allocated and connected to either PLCs ( Programmable Logic Controllers ) or microprocessors like RTUs ( Remote Terminal Units), which control the sensors and actuator according to a software program and send this information to a SCADA master via a means of communication, this communication could be wired or wireless. This system was developed to automate plants, cut cost and decrease labor.

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SCADA systems (Supervisory control and data acquisition) is design that controls plants using computers, communication e.g. (Data networks, Fiber Optics) and GUI (Graphical user interface) to achieve an elevated level of process supervision and management, in order to interface with plants and machinery it also uses devices like PLCs (programmable logic Controllers), RTUs (Remote Terminal units) and PIDs (Proportional–Integral–Derivative), an interface helps the operator to monitor the process and issue commands e.g. (set point changes) through the SCADA master computer, which then communicates this command to the logic controller of microprocessor that perform calculations and connects to plant sensors and actuators.
This system is was built on the concept that helps an operator have remote access to various controllers that are local to the plants, to access standard automation protocols. They are able to control large scale processes at different locations, this has made it into a common method often used by industries and manufacturers.

Functionality of SCADA systems is accounted to its fortitude in supervision over various other devices.
The following diagram is a generalized model of a SCADA system showing the stages of control that SCADA systems go through, the control is greatly computerized so that operators can interface with the machinery.

• Stage 0 consists of plant level devices like sensors and actuators, depending on the type of application these sensors may be temperature sensors, pressure sensors or any other type, same goes to the actuators, they may be valves, electric arms etc…
• Stage 1 consists of logic control modules such as PLCs and RTUs (Microcontrollers) which is where the sensors and actuators are connected to.
• Stage 2 consists of computers that have the SCADA software which supervises the operation and can override process, these computers have software that is pre-programmed to control and supervise the processes of the sensors and actuators via the logic controllers, they receive information from processor nodes and have interfaces for controlling and changing set points and alarms, further a historian records all data to enable data trending and analysis at higher stages.
• Stage 3 This stage is largely concerned with controlling the production level, it does not directly control like stage 2, however it monitors production rate to check wither target production is going to be met or not.
• Stage 4 At this stage the production schedule is created and monitored.
Since SCADA systems are typically large scale, it would be hard to follow every piece of equipment, hence a “tag” system is used for controlling every piece of equipment by referencing to the tag identification.


SCADA systems are based on the connection between complex devices, In order to match a large scale of instruments protocols are needed to set communication parameters between connecting devices, Some of the common protocols are listed below:
• Modbus: A standard for Logic controller communications, a Modbus network protocol allows devices to recognize other devices address and determine messages sent to it so action may be taken, the main disadvantage is that it cannot transfer large positive and negative numbers.
• Modbus X : fixes the Modbus issues and has a larger resolution or up to 9 digits and plus or minus 99 decimals.
• Distributed network protocol (DNP) : this protocol is commonly used in electric power systems, the only shortcoming is that it has many rules which has made industries hesitant to implement it, however the protocol is actively upgrading and is up to version 3.0.
• American Standard Code for Information Interchange (ASCII) : an old and tested protocol for computers, modems, printers and many sensors and actuators.
• IEEE 60870 : This protocol is mainly used in power transmission and distribution. It has become an international protocol and is spreading through many regions.


SCADA systems use these protocols to communicate either wirelessly or hard wired, some of the communication methods used are as follows:
Type Advantages Disadvantages
Telephone Line Readily exists on site Usually needs third party to fix line problems, and has slow speed
Ethernet Good for low distances like local sites Signal is lost further than 1 kilometer and needs boasting.
Fiber Optic Very fast data transmission rate and high bandwidth High cost of implementation and monthly fees
Coaxial Cable Readily exists on site, good bandwidth Monthly fees
Type Advantages Disadvantages
UHF and VHF Voice Radio
Low maintenance and easily repaired Frequency license needed
900Mhz spread spectrum and
2.4Ghz Data Radio No license needed and has a high data transmission rate Needs to be within line of sight
Wi-Fi Good choice for short distances, good transmission rate Range is limited
Microwave Good for connecting high places such as mountains Hard to implement
Cellular Most popular option because costs are declining, good transmission speed Area coverage must be inspected for good cellular connection
Satellite Good for harsh condition like remote areas Very costly

5.0 History and Generations

In 1950, computers were first invented, they were used by industries for control purposes, this has initiated the need for further supervision and control. In the 1960s, telemetry was established for monitoring, which allowed for automated communications to transmit measurements and other data from remotes sites to monitoring equipment. The term “SCADA” was coined in the early 1970s, and the rise of microprocessors and PLCs during that decade increased enterprises’ ability to monitor and control automated processes more than ever before.
In the 80s and 90s, SCADA continued to evolve thanks to smaller computer systems, Local Area Networking (LAN) technology, and PC-based HMI software. SCADA systems soon were able to be connected to other similar systems. Many of the LAN protocols used in these systems were proprietary, which gave vendors control of how to optimize data transfer. Unfortunately, these systems were incapable of communicating with systems from other vendors. These systems were called distributed SCADA systems.
In the 1990s and early 2000s, building upon the distributed system model, SCADA adopted an incremental change by embracing an open system architecture and communications protocols that were not vendor-specific. This iteration of SCADA, called a networked SCADA system, took advantage of communications technologies such as Ethernet. Networked SCADA systems allowed systems from other vendors to communicate with each other, alleviating the limitations imposed by older SCADA systems, and allowed organizations to connect more devices to the network.

5.0 History and Generations Contd.

First generation: “monolithic”
Historically speaking the first SCADA systems operated using minicomputers, no networks have yet come to exist. That’s why early SCADA systems were not connected to other systems and therefore independent. All protocols of that time were managed by the SCADA developers, a backup main frame system was usually used in case the primary main system failed. Some first generation SCADA systems were developed as “turn key” operations that ran on minicomputers such as the PDP-11 series made by the Digital Equipment Corporation.

Second generation: “distributed”
At this stage the LAN (Local area network) came into play, SCADA implemented LAN in order to distribute data to multiple stations all connected to LAN, Real time communication was performed, to utilize this network each particular station was tasked independently, at this point all protocols were still developed mainly by the SCADA developers.

Third generation: “networked”
More communication protocols were developed by both independent developers and by the original SCADA developers, the evolution in networking has made it able to connect several networks by LAN in a Process and Control network (PCN), these networks may be remote to each other while still be connected to one single supervisor that’s also able to store and analyze data (historian), it has become a very powerful tool in system control.

Fourth generation: “Internet of things”
In the advent of Cloud computing SCADA systems have started using the Internet of things so that it may be able to reduce costs, elevate security, increase compatibility, ease maintenance and increase speed. To be able to adapt to this technology, the main concept or central data allocation needs to be decentralized, a new concept have been developed based on object oriented programming, this concept is called “data modeling”, data modeling uses a virtual representation of each device which contains rel time information about each device.

6.0 Benefits and issues

• The Following are the benefits or advantages of SCADA:
1. Collect data that otherwise may be hard to collect and use.
2. The system is very customize able and flexible.
3. It can interface a virtually unlimited amount of activity which makes it versatile.
4. Can obtain real time simulation.
5. Easy to interface to preexistent PLCs and RTUs.
6. The advancement of protocols allows for data supervision from remote locations..
7. Usually have back-up systems which renders it more robust.
8. It is scalable and flexible in adding additional resources.
9. Wide range of applications available.
10. cuts the cost of production.
11. Allows us to study and analyze data using the historian so we may find trends and increase production quality and rate.

• Following are the issues or disadvantages of SCADA:
1. Implementation may be complex depending on the plant.
2. As the system is complex, it requires skilled operators, analysts and programmers to maintain SCADA system.
3. Installation costs are high.
4. The system increases unemployment rates.
5. Compatibility issues exist.

7.0 Components

Supervisory computers
The base of any SCADA system is its supervisory computer, this is where the data pools in from the logic controllers, data can come from processes and events that take place in the plant where filed devices like sensors and actuators are located. Depending on the size of the system there may be several work station connected to the logic controllers, theses work station all have HMI (human machine interface) which allows the operator to supervise the station, a master station may also include a single or several computers with HMIs, several servers may be used for data acquisition, distribution of software application and disaster recovery locations. To strengthen the system both primary and backup servers are often set on ready standby in case of system server crashes or malfunction.

Remote terminal units or Programmable logic controllers
RTUs Remote terminal units or PLCs is where sensors and actuators are connected to the I/O (input/output), PLCs are more easily configured, more versatile, and cost effective than RTUs, using protocols they communicate process information to the supervisory computers, they are always programmed and tested prior to production, some commonly used software to program PLCs are ladder logic, which is easily programmed and modified by the supervisory computers.

Communication infrastructure
As we discussed before in the communication section, using protocols logic controllers are connected to supervisory computers, this communication be in wired or wireless form, the supervisory computers monitor the process either in real time, or on a periodic basis, in case the communication is cut the plant does not stop working, and when communication is resumed the supervisory computer may resume monitoring, to prevent this from happening industries use dual redundant communication forms so if one fails the other continues to transfer data.

7.0 Components Contd.

Human-machine interface
HMI stands for human machine interface, it’s the window where operator may supervise the SCADA system, the HMI shows the site in a graphical representation often using schematics to view the instruments and devices in action, alarms and logs of trending data using graphs are also presented using the HMI, further the HMI is capable of creating reports, and sending notifications.
Graphical diagrams are lines and symbols that present process of devices, some installation may include an actual digital image with symbols drawn over it to show the actual process location and ease understanding.
The operator that supervises the plant using the HMI may perform overriding of the process in cases of alarm, or change a set point for an actuator or sensor simply by pointing a cursor and clicking on the symbol of event in real time.
Often the HMI package includes a drawing program, where operators may change the interface in a way that suits them.
Further the HMI collects data but does not delete it, it saves it in the historian, this way it can create trends and analyze the information so it may help production and understanding.

8.0 Power Distribution

Most cutting edge technology these days depends on computers to control solutions, this way it can cut the cost of production and improve reliability. Using computers allows for optimized operation, controlled decision making as well as damage management of a power system network. Being able to collect data SCADA system have proved to be an efficient solution in power operations.

Usually, SCADA systems used for electrical power distribution are used to automate a network by providing remote supervision, coordination, controlling and operating distribution components.
They replace manual labour with automated equipment, to improve efficiency of a power distribution system, SCADA operators use real-time view, data trends and logging, maintain optimal voltage and current, maintain power factors as well as generate alarms.

8.0 Power Distribution Contd.

SCADA does the following tasks in a power distribution system, automatic supervision, protects and controls equipment using logic controllers like (RTUs), it resumes power service in case of error condition, further it maintains optimal operating conditions.
Moreover, SCADA enhances the redundancy of supply by reducing duration of outages and also gives the cost-effective operation of distribution system. Therefore, distribution SCADA supervises the entire electrical distribution system. The major functions of SCADA can be categorized into following types.

• Substation Control
• Feeder Control
• End User Load Control

8.0 Power Generation and Distribution Contd.

• Substation Control using SCADA
In substation automation system, SCADA performs the operations like bus voltage control, bus load balancing, circulating current control, overload control, transformer fault protection, bus fault protection, etc.
SCADA system continuously monitors the status of various equipments in substation and accordingly sends control signals to the remote control equipments. Also, it collects the historical data of the substation and generates the alarms in the event of electrical accidents or faults.

8.0 Power Generation and Distribution Contd.

The above figure shows the typical SCADA based substation control system. Various input/output (I/O) modules connected to the substation equipment gathers the field parameters data, including status of switches, circuit breakers, transformers, capacitors and batteries, voltage and current magnitudes, etc. RTUs collect I/O data and transfers to remote master unit via network interface modules.
The central control or master unit receives and logs the information, displays on HMI and generate the control actions based on received data. This central controller also responsible for generating trend analysis, centralized alarming, and reporting.
The data historian, workstations, master terminal unit and communications servers are connected by LAN at the control center. A Wide Area Network (WAN) connection with standard protocol communication is used to transfer the information between field sites and central controller.
Thus, by implementing SCADA for substation control eventually improves the reliability of the network and minimizes the downtime with high speed transfer of measurements and control commands.

• Feeder Control using SCADA
This automation includes feeder voltage or VAR control and feeder automatic switching. Feeder voltage control performs voltage regulation and capacitor placement operations while feeder switching deals with remote switching of various feeders, detection of faults, identifying fault location, isolating operation and restoration of service.
In this system, SCADA architecture continuously checks the faults and their location by using wireless fault detector units deployed at various feeding stations. In addition, it facilitates the remote circuit switching and historical data collection of feeder parameters and their status. The figure below illustrates feeder automation using SCADA.

8.0 Power Generation and Distribution Contd.
In the above typical SCADA network, different feeders (underground as well as overhead networks) are automated with modular and integrated devices in order to decrease the number and duration of outages. Underground and overhead fault detection devices provide accurate information about transient and permanent faults so that at the remote side preventive and corrective measures can be performed in order to reduce the fault repeatability.
Ring main units and Remote Control Units (RTUs) of underground and overhead network responsible for maintenance and operational duties such as remote load switching, capacitor bank insertion and voltage regulation. The entire network is connected with a communication medium in order to facilitate remote energy management at the central monitoring station.
• End User Load Control Automation by SCADA
This type of automation at user end side implements functions like remote load control, automatic meter reading and billing generation, etc. It provides the energy consumption by the large consumers and appropriate pricing on demand or time slots wise. Also detects energy meter tampering and theft and accordingly disconnects the remote service. Once the problem is resolved, it reconnects the service.

The above figure shows a centralized meter data-management system using SCADA. It is an easy and cost-effective solution for automating the energy meter data for billing purpose.
In this, smart meters with a communication unit extract the energy consumption information and made it available to a central control room as well as local data storage unit. At the central control room, AMR control unit automatically retrieves, stores and converts all meter data.
Modems or communication devices at each meter provide secure two-way communication between central control and monitoring room and remote sites.

8.0 Power Generation and Distribution Contd.

• Advantages of Implementing SCADA systems for Electrical Distribution

Due to timely recognition of faults, equipment damage can be avoided
Continuous monitoring and control of distribution network is performed from remote locations
Saves labor cost by eliminating manual operation of distribution equipment
Reduce the outage time by a system-wide monitoring and generating alarms so as to address problems quickly
Improves the continuity of service by restoring service after the occurrence of faults (temporary)
Automatically improves the voltage profile by power factor correction and VAR control
Facilitates the view of historian data in various ways
Reduces the labor cost by reducing the staff required for meter reading


On the search of new NLO materials with better mechanical properties, many researchers have focused on the small organic molecules having a large dipole moment and a chiral structure. These molecules are usually linked through the hydrogen bond 1-2. Nonlinear optical (NLO) single crystals establish a variety of applications to perform functions like electro-optic switching, optical memory storage, frequency conversion, second harmonic generation and high energy lasers for inertial con?nement fusion research 3–7. Because of the large nonlinearities and optical threshold of organic materials, a wide range of such materials has been found by many researchers 8-10. In general, most of the organic molecules designed for nonlinear optical applications are the derivatives of an aromatic system substituted with donor and acceptor substituent 11-13. In recent years there have been extensive researches in the investigation of nonlinear optical crystals because of their potential applications in fabrication of optoelectronic devices 11–14.
The organic crystals have large nonlinearity, but they have poor mechanical and thermal stability and are susceptible to damage during processing. Moreover, the growth of large size single crystal is difficult to grow for the fabrication of devices. Inorganic crystals have excellent mechanical and thermal properties, but possess relatively modest optical nonlinearity because of the lack of extended pi-electron delocalization. Due to the above reasons, investigations have been made with semi-organic crystals which have combined properties of both organic and inorganic crystals and it is more suitable for device fabrication 15-19.
Sulphanilic acid (SAA) is a very interesting compound due to a number of medical, biological, NLO, irradiation and radiation dosimeter properties. SAA is virtually tissue equivalent, which enables its use in radiation therapy. EPR signal intensity shows noticeable stability of transfer dosimeter 20-24. SAA containing two functional groups like sulfonic acid (-So3H) and amine groups, thereby it acts as a base which makes a compound through nitrogen (amino) atom. In recent times, the growth and NLO properties of sulphanilic acid derivatives have been reported.
In this research article, the growth of transition metal incorporated novel SAA crystal grown from an aqueous solution involving electron transfer from donor to acceptor followed by hydrogen bond formed from the acceptor is presented. Also the characterization studies, like FT-IR, UV-Vis-NIR, X-ray diffraction, NMR, thermal, hardness, etching, EDAX analysis, nonlinear optical and dielectric properties were carried out and the obtained results are reported in the present work and discussed. These results are not yet reported in the literature to our knowledge.
2.1 Materials and spectral measurements
The compound Sulpanilic acid and Zirconium oxychloride are purchased from Sigma-Aldrich and Merck Chemicals Company. These chemicals were used without purification. The grown crystals have been subjected to single crystal X- ray diffraction studies using an ENRAF NONIUS CAD4 diffractometer with MoK? radiation (?=0.71073 A?) to determine the unit cell dimensions with space group. The powder samples have been analyzed by using BRUCKER, Germany (model D8 Advance) X-ray diffractometer with CuK (wavelength=1.5405A0) radiation. The powder sample was scanned over the range 10– 80oC at a scan rate of 1oC/ min. Infrared spectrum was recorded using the Alpha Bruker ATR technique with a resolution of 2 cm-1 at room temperature. 1H & 13C NMR spectra of the crystals were run on a Bruker FT-NMR spectrophotometer operated at 400 MHz at room temperature using dimethyl methoxide (DMSO) as a solvent and tetra methylsilane (TMS) as an internal reference. The optical transmission spectrum was recorded using DOUBLE BEAM UV-Vis-NIR Spectrophotometer (Model:2202) in the region 200-1200nm. Thermal stability of the crystals was done by thermogravimetric analysis (TGA) method using Dupont 951 thermogravimertic analyzers. The work was performed from 30 to 800°C at the heating rate of 200C min-1 in a nitrogen atmosphere with a gas flow rate of 100ml min-1. The Vicker’s hardness test was carried out on the grown crystal using SHIMADZU HMV microhardness tester fitted with a diamond pyramidal indenture. The surface morphology and particle sizes of the samples were determined by field emission scanning electron microscopy (FESEM; Hitachi S4800; Japan).
2.2 Synthesis of SAOZR crystals
The SAOZR has been synthesized by taking the chemicals in equimolar ratio and dissolved in aqueous solution. The solution was stirred well using a magnetically stirred at room temperature. The solution was kept in undisturbed condition and after 45 days transparent crystals of SAOZR in pyramidal shape were collected. These crystals are in yellow-reddish color with an average size of 8x7x15 mm3. The purity of the synthesized crystal was improved by successive re-crystallization process. The synthesis route is shown in figure 1.
2.3 Crystal Growth of SAOZR
The bulk growth of SAOZR single crystal was carried out from slow evaporation solution growth method and good quality single crystals were obtained. Figure 2 shows photographs of the as grown crystal. The optimized growth conditions of SAOZR single crystal are given in table 1. All the crystals have good compositional stability. Samples were stored at room temperature and at 90% relative humidity showed no degradation after several months. Fig. 2. The photograph of the as grown crystal of SAOZR.

3.1. Single Crystal X-Ray Diffraction (SXRD) Analysis
The single crystal X-ray diffraction studies of pure SAA and SAOZR crystal revealed that both pure and SAOZR single crystal crystallize in the orthorhombic system with space group belong to P212121. The lattice parameters are a= 7.31 Å, b = 7.51 Å, c = 13.92Å and volume =765 Å3 and slight variations in these values were observed in SAZOR crystal when compared with pure SAA. This type of variations may be recognized to the incorporation of zirconium oxychloride in the SAA crystal lattices. This result is presented in table 2.
3.2. Powder X-ray diffraction (PXRD) analysis
In powder XRD pattern, a well defined Bragg’s peak is obtained at specific 2? angles for SAOZR crystal. The crystallinity of SAOZR was confirmed by PXRD analysis and diffraction sharp peaks are indexed from crystal structure parameters shown in figure 3. This reveals that the grown crystal has good quality and possesses high crystalline nature. The variations of intensity of peaks compare with pure SAA crystal 24. It is clearly indicated that the doping (zirconium oxychloride) could be incorporated into the pure SAA crystal lattice.
3.3. FT-IR Spectral Analysis
The FT-IR spectral analysis of as grown crystal SAOZR was carried out between 4000 and 500 cm-1. The observed spectrum is shown in figure 4. The peak at 2648 cm-1 is assigned to hydrogen bonded N-H—O vibration of amine with zirconium oxychloride. The asymmetric bending vibration of NH3 of sulphanilic acid occurs at 1631 cm-1. The benzene ring resonance vibration produces peaks at 1598, 1549, 1578 and 1423 cm-1. The corresponding asymmetric vibration of SO3- vibration gives the peaks at 1318, 1246, 1158 and 1162 cm-1. The peak at 564 cm-1 is due to torsional oscillation of NH3+. The broad and intense peak due to C-H stretching, vibration appeared as a strong absorption band in the region 2881 and 3065 cm-1. The -NH2+ bending at 1598 cm-1 is shifted to a higher frequency region as 1631 cm-1 due to the presence of resonance structure (–NH3+ and -NH2+). The peak observed at 1318 cm-1 reveals C=S bend. Symmetric C=S stretching vibrations at 831 cm-1 is shifted to the low frequency region at 685 cm-1.
3.4. 1H and `13C NMR Spectra
Figures 5a and 5b represent the proton NMR and carbon NMR spectrum of SAOZR respectively. The presence of NH3+ protons in the synthesized SAOZR crystal appears at ?=4.3ppm in the 1H NMR spectrum. The aromatic protons are appearing around 6.8 and 7.1 ppm. The synthesized crystal SAOZR contains only aromatic carbon atom which appears in 13C NMR at ?=127ppm. Fig.5. 1H and `13C NMR spectrum of SAOZR crystal
3.5. Optical transmission studies
The optical transmission spectrum of SAOZR crystal is shown in Figure 6. The transmission is maximum in the entire visible region and infrared region. In the grown SAOZR crystal, the UV transparency cutoff wavelength lies at 247nm and the percentage of transmission is high in the entire visible region from 247nm to 1200nm. The absence of absorption in the entire visible region makes the SAOZR crystal as a potential candidate for second harmonic generation and optical applications
3.6. SHG efficiency studies
The Powder SHG test offers the possibility of assessing the non-linearity of new materials. Kurtz-Perry powder second harmonic generation (SHG) measurements were carried out using a spectrum-physics Q-switched Nd:YAG laser with the first harmonic input at 1064nm and a pulse width of 10ns at a repetition rate of 10Hz. This SHG efficiency diagram was shown in figure 7. The second harmonic signal generated by the compound was confirmed by emission of green radiation and the powder SHG efficiency of SAOZR was found to be comparable to that of Potassium Dihydrogen Phosphate (KDP). The SHG behavior was confirmed from the emission of bright green radiation (532nm). So it is a good NLO material for several applications.
3.7. Photoluminescence study of SAOZR crystal
The PL study finds wide applications in the field of medical, biochemical and chemical research for analyzing compounds. Photoluminescence in solids is the phenomenon in which electronic states of solids are excited by light of particular energy and the excitation energy is released as light. The photon energies reflect the variety of energy states that are present in the material. Figure 8 shows a PL emission spectrum recorded in the range of 300–800nm with an excitation wavelength of 341nm. The highest emission peaks in the spectrum were observed at 341nm and 667nm which indicates the emission of blue and red light. Other observed peaks are due to anionic and cationic nature of the sample.
3.8. Thermal analysis of SAOZR crystal
The thermogram and differential thermogravimetric traces are shown in Figure 9. It is observed from DTA curve, the material exhibits single sharp weight loss at 366.5 °C. It is observed that there is no weight loss from ambient temperature to 366.5 °C which indicates the grown SAOZR crystal is totally devoid of any inclusion of solvent and also indicating that the SAOZR crystal is stable up to 383.9 °C. At this decomposition stage, 86.8 % weight loss was observed from the thermogravimetric (TG) analysis.
3.9. Mechanical study of SAOZR crystal
The fastest and simplest type of mechanical testing is the Vickers microhardness measurement. Among the different testing methods, the Vicker’s hardness test method is more commonly used. Microhardness measurements were done on SAOZR for the applied load (p) varying from 25 to 100g for a constant indentation time 10s.Several indentations were made for each load and the diagonal length (d) of the indentation was measured.

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The Vickers hardness number was determined using the formula H? = 1.8544 P/d2 (Kg/mm2). A graph was plotted between H? and load (p) shown in Figure 10. For an indentation load of 100 g, crack was initiated on the crystal surface, around the indented. This is due to the release of internal stress locally initiated by indentation. The work hardening coefficient (n) has been calculated from the slope of a straight line between log p and log d from Figure 11 and it is found to be 2.9 which indicates moderately soft nature of material (25-27).
3.10. Dielectric Studies of SAOZR crystal
The dielectric constant and the dielectric loss of the SAOZR sample were measured using HIOKI 3532-50 LCR HITESTER. Dielectric constant and dielectric loss of the sample has been measured for different frequencies (100 Hz to 5 MHz) at different temperatures (308 to 368 K). Figures 12 and 13 shows the variations of dielectric constant and dielectric loss, respectively, as a function of frequency at different temperatures. It is observed from Figure 12 that the dielectric constant decreases with increase in frequency from 50 Hz to 5 MHz and then attains almost constant. The same trend is observed for other temperatures too. It is also observed that the value of dielectric constant increases with temperature. Such variations in higher temperature may be attributed to the blocking of charge carriers at the electrodes. The decrease of dielectric constant at low frequency region may be due to space charge polarization. Figure 13 indicates that as the frequency increases, the dielectric loss decreases exponentially and then attains constant. The low value of dielectric loss confirms that the sample possesses lesser defects.
3.11. Etching Analysis of SAOZR crystal
The etching study was demonstrated for 5 s and 10 s, and the observed etch patterns of as grown SAOZR crystals are shown in Figure 14a and 14b. From the Figure 14a, it is observed that there is a smooth surface and rectangular shape etch pits observed on the surface of the sample when the etch pattern was taken within 5s. In the etch pattern recorded for 10s, in addition to rectangle shape etch pits, the dark spot is also observed. These etch pits are due to the chemical impurities and crystal undergoes selective dissolution during growth.
3.12. EDAX Analysis of SAOZR crystal
The elemental analysis was done using the Oxford INCA Energy Dispersive Atomic X-ray Fluorescence Spectrometer (EDAX). From the analysis, it is noticed that the equal mole percentage of Zirconium Oxychloride sulphanillic acid has been incorporated into the as grown crystal of SAOZR. The element chloride was traced in EDAX analysis and shown in the figure 15. The chemical composition is also calculated theoretically as C, 25.79; H, 2.16; N, 5.01; O, 22.90; S, 11.48; Zr, 32.65 and these values agree with EDAX analysis.
1.13. FESEM
The surface morphology and the particle size of the crystal were evaluated through FESEM analysis and the results are displayed in Figure 16. From the figure, it is interpreted as Zirconium particle agglomerated on the surface of the crystal (17, 28).
Well developed good quality transparent crystal of (((4-sulfonatophenyl)ammonio)oxy)zirconium (SAOZR) was grown successfully by slow evaporation technique. A single crystal XRD study has been carried out to identify the lattice parameters and the grown crystal belongs to the orthorhombic crystal system. Powder XRD shows good crystallinity of the grown crystal. The UV cutoff wavelength of SAOZR crystal is found to be around 247nm, which reveals grown crystal is a potential candidate for NLO applications. TGA and DTA analysis were carried out to characterize the melting behavior and stability crystal. The emission of intense green light from SAOZR crystal confirms the nonlinear optical properties. Photoluminescence study shows in wide blue color light emission. The dielectric behavior of the sample has been analyzed with various frequencies at different temperatures. The mechanical strength of growing crystal was analyzed by the Vickers micro hardness tester. The elemental analysis was done by EDAX. The dielectric response of the these crystals was studied in the frequency range 50 Hz to 5MHz at various temperatures and the results are discussed. Finally, it is concluded that SAOZR crystal is suitable for industrial applications as it possesses good thermal stability, moderate SHG efficiency and soft nature.


1.0 Pengenalan
Berfikir ialah proses semula jadi. Kita sering kali ditekankan oleh orang yang lebih berkuasa untuk lebih berfikir dan “menggunakan akal” tetapi apa sebenarnya yang perlu kita ketahui adalah bagaimana untuk melakukan proses berfikir secara teliti serta kemahiran berfikir secara reflektif. Kerana individu hari ini sudah terbiasa dengan jawapan yang mudah dan jalan penyelesaian yang sedia ada untuk digunakan sedangkan masalah dan cabaran dalam kehidupan adalah sukar dan kompleks.
Oleh itu, masalah ini sebenarnya memerlukan kita memupuk pemikiran lebih mendalam dan bukan hanya sekadar berfikir di peringkat permukaan contohnya pengurusan dalam organisasi antara pengurus yang bernama Janice dan pekerjanya Rogers yang telah bekerja di syarikat GHJ selama hampir 15 tahun dan rogers sukakan pekerjaannya kerana rakan-rakannya yang ramah dan suka membantu.Dengan tempat kerja terletak berhampiran dengan rumahnya. Walau bagaimanapun, dia tidak begitu gembira kerana pengurus yang baru itu sangat keras kepala. Dia tidak sopan ketika membuat permintaan dari orang bawahannya untuk melakukan tugas. Bila Janice iaitu penurusnya yang tidak berpuas hati dengan kerja yang disiapkan oleh kakitangannya, dia boleh sahaja meledak dengan kemarahan di hadapanumu. Ini telah menjadikan Rogers berfikir sama ada untuk terus bekerja atau berhenti,dalam konteks ini kita membincangkan isu, masalah kes tersebut dan penyelesaian kepada masalah ini dan apa-apa model atau teori dan strategi serta kenalpasti apa-apa model . Antara objektif yang boleh dibincangkan adalah :
i. Untuk meningkatkan kemahiran berfikir secara kritikal dan kreatif para pelajar
ii. Untuk mendedahkan pelajar kepada pelbagai cara penyelesaian masalah yang yang boleh digunakan dalam kehidupan seharian.
iii. Dan pelajar boleh memberi idea dan pandangan dengan menggunakan sumber yang berkaitan.
iv. Untuk mengenalpasti masalah isu kes yang perlu diatasi dan menyelesaikan masalah.
v. Mengenalpasti strategi yang boleh digunakan dan berkaitan dengan masalah yang dihadapi oleh Rogers.
Perlu difahami bahawa setiap nilai pembacaan paling berharga bukannya informasi yang kita perolehi tetapi apa sebenarnya yang kita fahami dan fikir serta bagaimana kita memproses informasi semasa membaca. Oleh yang demikian pilihan bahan pembacaan sangat penting untuk diambil kira kerana seseorang perlu fahami bahawa objektif utama membaca bukan untuk memenuhkan minda dengan informasi tetapi untuk memberi ruang untuk minda berfikir dan membuat pertimbangan. Pembaca perlu berhenti seketika dari semasa ke semasa untuk meneliti dan membuat kesimpulan tentang apa yang telah dibaca. Ini akan merangsang proses pemikiran serta berupaya mengaplikasikan apa yang telah dibaca dalam kehidupan seharian. Kejelasan ialah kuasa dan ia lahir daripada berfikir.
Manusia bukan hanya perlu berfikir tetapi perlu memikirkan dengan lebih mendalam tentang pilihan dan kearah kehidupan mereka. Masa ialah sumber paling berharga yang seseorang individu ada. Dipercayai kehidupan seseorang itu ialah jumlah keseluruhan apa yang dilakukan dengan masa tersebut. Oleh itu, sesungguhnya amat berharga melabur lebih banyak masa dalam proses berfikir secara mendalam dan konstruktif.


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