Experimental investigations on fibre reinforced geopolymer concrete as repair material for pavements

Geopolymer is a relatively new construction material which could be produced by the chemical action between alumino-silicate material such as fly ash and alkaline solutions like sodium silicate or sodium hydroxide. Geopolymer concrete (GPC) reduces the CO2 emission by 9 % compared to the concrete made with ordinary portland cement. Fibre reinforced geopolymer concrete (FRGPC) has already been used as a repair material for different construction purposes such as for tunnel linings and sewage pipes repairs due to its improved tensile characteristics and crack control properties. This study involves the experimental investigations on FRGPC as a repair material for rigid pavements. A mixture of sodium silicate and 8M sodium hydroxide solution is used as the alkaline activator to prepare the fly ash based geopolymer concrete. To increase the mechanical properties at ambient temperature calcium additives in the forms of calcium hydroxide and calcium oxide are added separately by replacing fly ash in the proportion 3%, 5% and 7% by weight of fly ash. Further to increase the low tensile strength of GPC, addition of polypropylene fibre in 0.2%, 0.4% and 0.6% by volume of concrete were also incorporated. The aspect ratio of the polypropylene fibres used is 300. The optimum values were determined based on the fresh concrete properties and mechanical properties. The results showed that the 7 day compressive and tensile strengths of FRGPC were increased by 36% and 14% respectively from fly ash GPC. The bond strength between the pavement substrate and the geopolymer repair material is also studied. The bond strength of the fibre reinforced repair material is found to be more than the permissible values as per relevant codes of practice. Abrasion resistance of the repair material is also tested as a measure of durability aspects to check the suitability for usage on rigid pavements. Keywords—Geopolymer Concrete, Alumino-Silicate, Rigid pavements, Substrate, Alkaline solution, Repair materia

Examining the Relationship between Tobacco Use and Perceptions of a New Tobacco-Free Campus Policy

The purpose of this study was to examine the perceptions of tobacco-free policy benefits and enforcement on a campus with a tobacco free policy. Young adults aged 18 to 24 have the highest rate of tobacco use compared with all other age groups in the United States, and are the most targeted by the tobacco industry. Experts recommend that smoke-free and tobacco-free areas are the most effective ways to reduce exposure to secondhand smoke and encourage cessation. Surveys were distributed on a campus three years after the implementation of the tobacco-free policy. The study included 198 participants (n=198) and 14% of the participants self-reported as tobacco-users. The results confirmed that students who use tobacco products do have a different perception of the tobacco-free campus policy

Durability of geopolymer concrete exposed to acidic environment – a review

Acids attack concrete by dissolving both hydrated and unhydrated cement compounds as well as calcareous aggregates and the subsequent chemical reaction forms water soluble calcium compounds which are then leached away. The aggressiveness of the reaction depends on the pH of the acidic medium and the types of salts formed. Concrete pipes made of ordinary portland cement (OPC) carrying sewage water have always the presence acidic solutions in it. They deteriorate and service life of the pipes is affected along with the increased maintenance costs and that process cause environmental impacts.  Geopolymer binders are novel binders that relies on alumina silicate rather calcium silicate bonds for structural integrity so they have been reported as being acid resistant. Those could be produced by the chemical action between alumino-silicate material such as fly ash(FA), granulated blast furnaces slag (GGBS), metakaoline or silica fume with alkaline solutions like sodium silicate or sodium hydroxide. Geopolymers show superior performance in terms of corrosion and fire resistance due to the absence of water and calcium in their structure.Utilisation of waste materials like FA and GGBS makes geopolymer    concrete (GPC) an environment friendly construction material. This review paper looks in to the effect of various acids such as sulphuric acid, acetic acid, nitric acids on durability properties of OPC specimens, GPC specimens and GPC composite specimens when immersed in acidic solutions for certain period. The performance of geopolymer is analysed by the visual inspection and studying the parameters like weight loss, loss in compressive strength and maximum depth of penetration. Keywords- Geopolymer concrete, Sodium hydroxide, sodium silicate, metakaoline, silica fume, alumina silicat

EFEKTIFITAS HYPNOTHERAPY UNTUK MENGATASI KETERGANTUNGAN NARKOTIKA PADA REMAJA DI LEMBAGA PEMBINAAN KHUSUS ANAK KOTA PEKANBARU

Banyaknya remaja yang saat ini mengkonsumsi narkotika berupa ganja, sabu dan sebagainya. berawal dari coba-coba dan keingin tahuannya tinggi. Remaja yang sudah merasakan efek dari narkotika akan sulit melepaskan diri dari narkotika. Jika narkotika sudah masuk kedalam tubuh baik melalui mulut, jarum suntik ataupun hisap, maka zat tersebut akan merusak system saraf pusat dan fungsinya. Akibatnya pengguna narkotika akan ketagihan secara fisik dan psikis serta pecandu juga akan sulit untuk fokus. Penelitian ini bertujuan untuk mengetahui perubahan yang terjadi pada pecandu narkotika di LPKA. Metode hypnotherapy dijadikan untuk menghentikan kebiasaan menggunakan narkotika dikalangan remaja. Metode hypnotherapy memerlukan waktu dan penyesuaian terlebih dahulu terhadap klien yang mengalami kecanduan. Kerjasama yang baik antara hipnoterapis dan klien menjadi hal yang sangat penting untuk kelangsungan terapi. Hipnoterapi memberikan efek yang rileks pada saraf otak yang menegang akibat zat addaktif narkoba. Hypnotherapy memanfaatkan sugesti dalam terapinya, tata laksana dalam hypnotherapy dengan wawancara pra-induksi atau pre-talk dan sugestivitas,induksi,deepening dan depth level test,suggestion dan termination. Imiplikasi yang terjadi pada klien setelah mendapatkan hypnotherapy adalah klien merasa nyaman, tenang, bahagia, stamina meningkat serta mampu berpikir lebih bijak. Dari serangkaian pelaksanaan hypnotherapy hasil menunjukkan bahwa hypnotherapy tidak cukup efektif untuk mengatasi kecanduan pada remaja di lembaga pembinaan khusus anak kota Pekanbaru. Factor yang menyebabkan kurang efektif nya hypnotherapy diantara nya tidak adanya kepercayaan klien dengan peneliti dalam melakukan terapi, kurang mendukung nya tempat yang digunakan untuk terapi, dan kurang terampilnya peneliti dalam melakukan terapi

Digital Watermarking Technique used for Security of Digital Images during Broadcasting and Telecasting by Using DWT

Signals are any time varying quantity having lot of Information and have its own frequency. Signal can be classified into random signal, periodic signals, and non-periodic signals, discrete or digital signal. Signal may contain various data like audio, vedio, or in text format. Signal also has information like images. But question arises of security of signal. So; Signals can be making secure by using the different Security techniques such as encryption and decryption by using RSA algorithm, Stegnography, Digital watermarking techniques. In this paper we are going to discuss transmission of Signal and their modulation techniques and its security by using “Digital Watermarking Techniques” with help of “Discrete Wavelet Transform”

Refractory vasospasm of the left anterior descending artery causing hemodynamic instability after percutaneous coronary intervention

Refractory coronary vasospastic angina is prone to fatal outcomes. Therefore, it is crucial that the most suitable treatment strategy be promptly elected so as to avert further cardiac complications. Here, authors present the clinical course of profound refractory coronary vasospastic angina in a 50-year-old man. Authors elected to manage the patient through stent implantation. Despite, a complication of perforation followed by refractory coronary vasospasm, authors elected to implant a second stent to relieve the patient from all symptoms

STUDY OF RATIONAL PRESCRIBING AND DISPENSING OF PRESCRIPTIONS WITH NONSTEROIDAL ANTI-INFLAMMATORY DRUGS IN ORTHOPEDIC OUTPATIENT DEPARTMENT

ABSTRACTObjective: To study the prescribing pattern of non-steroidal anti-inflammatory drugs (NSAIDs) in outpatient orthopedic hospitals from a rural areaof Maharashtra, India.Methods: A total of 237 prescriptions containing NSAIDs evaluated for their distribution according to the classification of NSAIDs and World HealthOrganization core indicators for prescribing practices and patient care.Results: The average number of drugs per prescription was 3.5. The average number of NSAIDs per prescription found to be 1.12. The incidenceof generic prescribing was very low. The overall average consultation time and dispensing time found to be 4.5 and 1.9 minutes respectively.The percentage of drugs adequately labeled was 61.44%. Out of the 843 drugs, 267 were systemic NSAIDs, of which 50.56% and 49.43% usedas monotherapy and fixed dose combinations respectively. The prescriptions are containing either one or two NSAIDs. Non-selective NSAIDs mostcommonly prescribed than selective cyclooxygenase-2 (COX2) inhibitors and highly selective COX2 inhibitors. The ratio of non-selective to selectiveNSAID usage pattern was 1:1.28.Conclusion: The study shows more use of traditional NSAIDs and underutilization of COX2 inhibitors. The study suggests that there is the immensescope of improvement for prescribing in the hospitals.Keywords: Prescribing pattern of non-steroidal anti-inflammatory drugs, Rational use of non-steroidal anti-inflammatory drugs, World HealthOrganization core drug use indicators

Optical pumping via incoherent Raman transitions

A new optical pumping scheme is presented that uses incoherent Raman transitions to prepare a trapped Cesium atom in a specific Zeeman state within the 6S_{1/2}, F=3 hyperfine manifold. An important advantage of this scheme over existing optical pumping schemes is that the atom can be prepared in any of the F=3 Zeeman states. We demonstrate the scheme in the context of cavity quantum electrodynamics, but the technique is equally applicable to a wide variety of atomic systems with hyperfine ground-state structure.Comment: 8 pages, 4 figure