The study of the growth mechanism of TiO2 nanotubes and their applications

This research project focused on the creation of nanomaterials and their applications. The main aim was to control the growth of TiO2 nanotubes with various morphologies and to investigate potential applications for controlled drug release and for photocatalytic water splitting. The electrochemical anodisation process in fluoride-containing organic electrolytes was employed to prepare vertically aligned TiO2 nanotubular arrays, with inner diameters of individual nanotubes ranging from 50 to 150 nm. A variety of morphologies was created by precise control of experimental conditions and parameters. The formation of crystal phases in the TiO2 nanotubes was controlled by the annealing temperature (in air) and monitored by powder X-ray diffraction (XRD). The fundamental anodisation parameters affecting the morphologies, such as anodisation voltage, electrolyte composition, stirring and the effect of magnetic fields were investigated. Various processing procedures that affect the anodisation process have been studied. The influence of hydroxide islands on the growth mechanism was shown by analysis of anodisation current-time profiles, contact angle measurements and SEM observations. The effect of pre-patterns on the Ti substrate was also studied. The substrate was patterned either mechanically or by Electron Beam Lithography (EBL) with polymethylmethacrylate (PMMA) as a positive photoresist. Instead of circular nanotubes, polygonal TiO2 nanotubes were formed from the mechanically patterned substrate whereas rectangular and tube-in-tube TiO2 nanotubes were formed by using EBL. The TiO2 nanotubes were used as photoanodes for photocatalytic water splitting using a photoelectrochemical cell for generating hydrogen gas. The effects of nanotube morphology and crystal structure on the efficiency of the conversion of photon energy to chemical energy were studied on samples annealed at various temperatures, and with a range of organic hole scavengers. In addition, control of the morphology was realised by surface passivation with organic thin films and by the control of the anodisation parameters. With stepwise control, bottle shaped nanotubes (nanobottles) were designed and created for their application in controlled drug release. Scanning and transmission electronic microscopy (SEM and TEM) were used to examine the structure and morphology of the nanotubes. The surface composition was studied by X-ray Photo-electron Spectroscopy (XPS) and Energy Dispersive X-ray Spectroscopy (EDX). Crystal phases were identified by XRD

Effect of creep on time-dependent behaviour of prestressed concrete integral abutment bridge

A parametric study was conducted to assess effect of creep on long term behaviour of prestressed concrete Integral Abutment Bridge (IAB). Varying backfill soil types were provided behind the bridge abutment and the interaction was modelled using linear springs. The effect of backfill soil type on the behaviour of the bridge was assessed through 75-year time-history simulations carried out in Commercial Finite Element Software (LUSAS). CEB-FIP 1990 creep model was used to analyse the linear viscoelastic behaviour of creep. The result has shown that creep and backfill soil type have a no severe effect on the behaviour of the bridge

Study on Optical Properties of Tin Oxide Thin Film at Different Annealing Temperature

Tin Oxide (SnO2) thin film is one of the important transparent conducting oxides (TCOs) and applied in various fields such as in solar cells, optoelectronic devices, heat mirror, gas sensors, etc due to its electrical and optical transparency in visible light spectrum. In this paper, we presented the optical properties of tin oxide thin film at four different annealing temperatures (373 K, 437 K, 573 K and 673 K) prepared by radio frequency sputtering technique. The optical characteristic of these films was investigated using the UV-VIS 3101-PC Spectrophotometer. From this study, all samples exhibit high transmittance more than 70% in the visible light spectrum. Sample annealed at 473 K shows the maximum transmittance which is 87%. Refractive index, n were in the range of 2.33 – 2.80 at = 550 nm and enhanced with the annealing temperature. However the extinction of coefficient, k was found to be very small. The optical band-edge absorption coefficients were found in the range of 104 – 105cm-1. The energy gap value was decreased with increasing annealing temperature and the type of photon transition was allowed direct transition

Rancang Bangun Media Pembelajaran Android Untuk Pembelajaran Komputer dan Jaringan Dasar

Proses pembelajaran yang ada di SMK Negeri 1 Bulango Selatan tidak berjalan maksimal dikarenakan masih dalam kondisi pandemi. Pada mata pelajaran Komputer dan Jaringan Dasar yang merupakan mata pelajaran program keahlian yang seharusnya dipelajari dengan cara interaktif, tetapi proses pembelajarannya hanya sekedar mencatat materi yang diberikan oleh guru. Penelitian ini bertujuan untuk menghasilkan sebuah media pembelajaran yang berbasis android untuk membantu memfasilitasi guru dan siswa agar bisa digunakan dalam pembelajaran mata pelajaran komputer dan jaringan dasar kelas X TKJ di SMK Negeri 1 Bulango Selatan. Metode penelitian adalah Penelitian dan Pengembangan (RD) model MDLC. Hasil penelitian melalui pengujian kelayakan media pembelajaran berbasis android oleh dua orang ahli materi diperoleh presentase kelayakan sebesar 100% dengan kategori sangat layak. Untuk hasil pengujian kelayakan media oleh dua orang ahli media masing-masing memperoleh presentase kelayakan sebesar 100% yang dapat dikatakan “sangat layak”. Adapun untuk hasil uji coba pengguna yang dilakukan pada 29 orang siswa mengenai tanggapan siswa terhadap media pembelajaran mendapatkan skor rata-rata sebesar 90% dengan kategori sangat praktis. Pengolahan uji validitas instrumen pada 19 item pernyataan pada kuisioner penilaian pengguna dengan menggunakan SPSS 25 menunjukkan hasil valid dan uji reliabilitas memperoleh nilai Alpha Cronbach’s sebesar 0,838 yang menyatakan bahwa instrumen sangat reliabel. Berdasarkan data tersebut dapat disimpulkan bahwa media pembelajaran berbasis android pada mata pelajaran Komputer dan Jaringan Dasar yang dirancang di SMK Negeri 1 Bulango Selatan layak digunakan dalam proses pembelajaran

Signature-based anomaly intrusion detection using integrated data mining classifiers

As the influence of Internet and networking technologies as communication medium advance and expand across the globe, cyber attacks also grow accordingly. Anomaly detection systems (ADSs) are employed to scrutinize information such as packet behaviours coming from various locations on network to find those intrusive activities as fast as possible with precision. Unfortunately, besides minimizing false alarms; the performance issues related to heavy computational process has become drawbacks to be resolved in this kind of detection systems. In this work, a novel Signature-Based Anomaly Detection Scheme (SADS) which could be applied to scrutinize packet headers' behaviour patterns more precisely and promptly is proposed. Integrating data mining classifiers such as Naive Bayes and Random Forest can be utilized to decrease false alarms as well as generate signatures based on detection results for future prediction and reducing processing time. Results from a number of experiments using DARPA 1999 and ISCX 2012 benchmark dataset have validated that SADS own better detection capabilities with lower processing duration as contrast to conventional anomaly-based detection method

Failure Mode Effect Analysis in Turning of Mild Steel Under MQL Condition

FMEA was commonly used to improve production quality by reducing workplace failures and preventing them from happening. Nowadays, tool failures are the most common problems that can be found in the machining practice. Hence, FMEA was used to reduce tool failure occurrence and improve the production quality. In this paper, FMEA analysis was done for a turning process of mild steel. Several turning operations were done, and the failure mode and failure effect were identified. Then, the tool failure effect was studied, and the causes were generated using the Ishikawa diagram. The occurrence, severity, and detection rating were assigned, and the Risk Priority Number (RPN) was generated. FMEA Risk Matrix was used to help provide a visual aid for classifying and categorizing the level of risk. The highest risk was then identified from the highest RPN value, and the cause and prevention methods were generated for each failure effect cause. This study can be used as a guide or reference in the turning process practice for a more effective process. &nbsp

Failure Mode Effect Analysis in Turning of Mild Steel Under MQL Condition

FMEA was commonly used to improve production quality by reducing workplace failures and preventing them from happening. Nowadays, tool failures are the most common problems that can be found in the machining practice. Hence, FMEA was used to reduce tool failure occurrence and improve the production quality. In this paper, FMEA analysis was done for a turning process of mild steel. Several turning operations were done, and the failure mode and failure effect were identified. Then, the tool failure effect was studied, and the causes were generated using the Ishikawa diagram. The occurrence, severity, and detection rating were assigned, and the Risk Priority Number (RPN) was generated. FMEA Risk Matrix was used to help provide a visual aid for classifying and categorizing the level of risk. The highest risk was then identified from the highest RPN value, and the cause and prevention methods were generated for each failure effect cause. This study can be used as a guide or reference in the turning process practice for a more effective process. &nbsp

Prevalence Of Pityriasis Alba Disease Among Primary Schools Children In Al-Kufa City.

ألخلاصة: أجريت هذه الدراسة المقطعية في قضاء الكوفة/ محافظة النجف الاشرف لتحديد نسبة الإصابة بمرض داء النخالية البيضاء ,هدف الدراسة: تحديد نسبة الإصابة بمرض النخالية البيضاء عند تلاميذ المدارس الابتدائية, مكان الدراسة: المدارس الابتدائية في قضاء الكوفة/ محافظة النجف الاشرف حجم عينة الدراسة :العدد الكلي للمدارس الابتدائية التي شملتها الدراسة 38 مدرسة و عدد التلاميذ  الكلي فيها 18356. تاريخ جمع العينة:الفترة من 1 / 10 / 2011  لغاية 31 / 4 / 2012 .التحليل البياني :التحليل البياني باستخدام التحليل الإحصائي الوصفي المتضمن (مربع كاي)  .النتائج: بينت الدراسة أن عدد المصابين بداء النخالية البيضاء 1935 بنسبة (10.54%)، وعدد الذكور المصابين 1067 (55.14%) وعدد الإناث 868 (44.86%) و نسبة الإصابة بداء النخالية البيضاء عند الذكور أكثر من الإناث  والفئة  العمرية بين (6 – 8) سنة أكثر الفئات تعرضاً للإصابة من الفئات العمرية الأخرى، كما وتبين إن البقع البيضاء أكثر وضوحاً عند الأطفال  ذوي البشرة السمراء من الأطفال ذوي ألبشرة البيضاء، ولوحظ أن ظهور البقع في الوجه أكثر من بقية أجزاء الجسم الأخرى، وان عدد المصابين اللذين يعانون من فقر الدم 232 من المصابين بنسبة  (12%)، 242  بنسبة  12.5% يعانون من الإصابة بالديدان الدبوسية، وطفيلي الجيارديا لامبيليا، والانتيميبا الحالة للنسيج فضلا عن وجود طفيليات معوية أخرى.الاستنتاجات : في هذه الدراسة تبين بان نسبة الإصابة بداء النخالية البيضاء كانت مقبولة مقارنة بالدراسات المشابهة التي أجريت في عدة أقطار و ذلك يعكس الإهمال ,قلة العناية الشخصية,نقص التغذية, وقلة الرعاية الصحية الأولية.التوصيات : بناءا على نتائج هذه الدراسة نوصي بإجراء  الفحص الطبي في بداية العام الدراسي , إجراء الفحص الدوري للتلاميذ ذات أهمية .التربية الصحية للمعلمين والآباء حول العناية الصحية الشخصية و نظافة البيئة .مفردات البحث :تحديد نسبة , مرض النخالية البيضاء, تلاميذ المدارس الابتدائية .الكوفة.Abstract         This is a cross-sectional study was conducted in Al-Kufa city/ Al-najaf Al-Ashraff  province to determine the prevalence of pityriasis alba in the children of primary school. Study aims  to determine the prevalence of Pityriasis alba in the children of primary schools. The setting of study: The study was conducted in Al-Kufa city /Al-Najaf Al-Ashraff  province.Data collection : During  the period  from  1/4/2011 to 31\4\2012. The study sample: The total number of primary school submitة ted was 38 and the number of total pupil were 18356, and founded the number of infected pupil with pityriasis alba was 1935 with percentage (10.54%), number of male was 1067 (55.14%) and number of  female was 868(44.86%).Data analysis: The data was analyzed through the application of descriptive statistical analysis that include)Chi-square) , and application of inferential statistical analysis that include (chi-square , P value) . Results: The results of this study showed that the prevalence of pityriasis alba in the male is more than in the female, the more exposed  infected age  group was  between (6-8 year). The white patches were more clear in dark color, appearance of  patches  in the face  was more clear than other parts of the body. The number of  pupil who suffered from anemia was 232 (12%), and 242 (12.5%) suffered from infected with Oxyuris vermicularis, Giardia lamblia, Entamoeba  histolytic  and other parasites. Conclusion: We conclude in this study that the prevalence of pityriasis alba was acceptable in comparison with other similar studies in many countries, this may reflect some negligence, poor personal hygiene and nutrition in primary schoolchildren, care health provided was inadequate.Recommendation: Based on the above results, this study recommended that the primary health care sector must examine the children in beginning of study. Periodic skin examination is of a high value. Health education for teachers and parents on sound personal hygiene and clean environment are recommended.Keyword: Prevalence, Pityriasis alba, Primary schools

Transverse slab reinforcement design of concrete bridge deck: A review

This paper reviews the current design practices of transverse slab reinforcement design in concrete bridge deck, which consist of concrete deck slab on wide concrete T-beams. The conventional bridge design method results in the provision of excessive transverse steel reinforcement in the concrete bridge deck slab due to the fact that, the slab is assumed to bear the applied vehicular loadings alone without considering the contribution of the wide T-beam flanges. Thus, the design which is based on bending and failure proved to be too conservative. Through critical review, issues regarding some design approaches were discussed. It has been found that, designing the deck slab in transverse direction would enable the vehicle wheel loads to be supported by the wide T- beam flanges and performance enhancement can be achieved by compressive membrane action resulted from the natural stiffness of the wide girder flanges. The presence of this membrane forces provides a punching shear capacity, which is far beyond the flexural design capacity for the new bridge deck system. This capacity would result in substantial reduction of the transverse reinforcement within the slab