The effect of (Ti + Al): V ratio on the structure and oxidation behaviour of TiAlN/VN nano-scale multilayer coatings

Nano-scaled multilayered TiAlN/VN coatings have been grown on stainless steel and M2 high speed steel substrates at U-B = - 85 V in an industrial, four target, Hauzer HTC 1000 coater using combined cathodic steered arc etching/unbalanced magnetron sputtering. X-ray diffraction (XRD) has been used to investigate the effects of process parameters (Target Power) on texture evolution (using texture parameter T*), development of residual stress (sin(2) psi method) and nano-scale multilayer period. The composition of the coating was determined using energy dispersive X-ray analysis. The thermal behaviour of the coatings in air was studied using thermo-gravimetric analysis, XRD and scanning electron microscopy. The bi-layer period varied between 2.8 and 3.1 nm and in all cases a {1 1 0} texture developed with a maximum value T* = 4.9. The residual stress varied between -5.2 and -7.4 GPa. The onset of rapid oxidation occurred between 628 and 645 degreesC depending on the (Ti+Al):V ratio. After oxidation in air at 550 degreesC AlVO4, TiO2 and V2O5 Phases were identified by XRD with the AlVO4, TiO2 being the major phases. The formation of AlVO4 appears to disrupt the formation of Al2O3 which imparts oxidation resistance to TiAlN based coatings. Increasing the temperature to 600 and 640 degreesC led to a dramatic increase in the formation of V2O5 which was highly oriented (0 0 1) with a plate-like morphology. At 640 degreesC there was no evidence of the coating on XRD. Increasing the temperature to 670 degreesC led to further formation of AlVO4 and a dramatic reduction in V2O5. (C) 2003 Elsevier B.V. All rights reserved

In-situ measurements of alloy oxidation/corrosion/erosion using a video camera and proximity sensor with microcomputer control

Two noncontacting and nondestructive, remotely controlled methods of measuring the progress of oxidation/corrosion/erosion of metal alloys, exposed to flame test conditions, are described. The external diameter of a sample under test in a flame was measured by a video camera width measurement system. An eddy current proximity probe system, for measurements outside of the flame, was also developed and tested. The two techniques were applied to the measurement of the oxidation of 304 stainless steel at 910 C using a Mach 0.3 flame. The eddy current probe system yielded a recession rate of 0.41 mils diameter loss per hour and the video system gave 0.27

Decreased myocardial injury and improved contractility after administration of a peptide derived against the alpha-interacting domain of the L-type calcium channel.

BackgroundMyocardial infarction remains the leading cause of morbidity and mortality associated with coronary artery disease. The L-type calcium channel (IC a-L) is critical to excitation and contraction. Activation of the channel also alters mitochondrial function. Here, we investigated whether application of a alpha-interacting domain/transactivator of transcription (AID-TAT) peptide, which immobilizes the auxiliary β2 subunit of the channel and decreases metabolic demand, could alter mitochondrial function and myocardial injury.Methods and resultsTreatment with AID-TAT peptide decreased ischemia-reperfusion injury in guinea-pig hearts ex vivo (n=11) and in rats in vivo (n=9) assessed with uptake of nitroblue tetrazolium, release of creatine kinase, and lactate dehydrogenase. Contractility (assessed with catheterization of the left ventricle) was improved after application of AID-TAT peptide in hearts ex vivo (n=6) and in vivo (n=8) up to 12 weeks before sacrifice. In search of the mechanism for the effect, we found that intracellular calcium ([Ca(2+)]i, Fura-2), superoxide production (dihydroethidium fluorescence), mitochondrial membrane potential (Ψm, JC-1 fluorescence), reduced nicotinamide adenine dinucleotide production, and flavoprotein oxidation (autofluorescence) are decreased after application of AID-TAT peptide.ConclusionsApplication of AID-TAT peptide significantly decreased infarct size and supported contractility up to 12 weeks postcoronary artery occlusion as a result of a decrease in metabolic demand during reperfusion

Kinetika Perubahan Mutu Minyak Buah Merah (Pandanus Conoideus) Selama Penyimpanan

Minyak buah merah (Pandanus conoideus) mengandung asam lemak tidak jenuh tinggi sehingga mudah teroksidasi dan mempengaruhi mutunya selama penyimpanan. Penelitian ini bertujuan untuk menentukan stabilitas oksidasi minyak buah merah dan mendapatkan model kinetika kerusakan oksidatif mutu minyak buah merah selama penyimpanan pada suhu kritis. Minyak buah merah yang akan diuji stabilitas mutunya dikemas dalam botol gelap pada suhu 60 °C, 75 °C, dan 90 °C, kemudian dilakukan pengamatan terhadap kadar air, kadar asam lemak bebas (ALB), bilangan peroksida dan total karotenoid selama ±15 hari. Hasil penelitian menunjukkan bahwa mutu minyak buah merah menurun dengan meningkatnya suhu dan lama penyimpanan. Peningkatan kadar ALB dan bilangan peroksida minyak buah merah mengikuti orde nol, dengan nilai Ea berturut-turut 37.709 J/mol °K dan 29.437 J/mol °K; sedangkan penurunan kadar karotenoid mengikuti orde 1 dengan nilai Ea 78.113 J/mol °K. Bilangan peroksida minyak buah merah paling sensitif terhadap kerusakan oksidatif selama penyimpanan karena memiliki nilai Ea terendah. Pendugaan umur simpan minyak buah merah berdasarkan kenaikan nilai ALB dan peroksida mengikuti persamaan A=Ao-(t.eksp[5,6-4.536(1 /T)]) dan A=Ao-(t.eksp[4,7-3.541(1/T)). Sementara umur simpan berdasarkan penurunan kadar karotenoid mengikuti persamaan ln A=ln Ao-(t[20,8-9.395(1/T)) dimana A= kadar akhir; Ao= kadar awal; t= lama penyimpanan (jam); dan T= suhu penyimpanan (°K)

Profil Tinggi Badan Anak Usia Baru Masuk Sekolah (Tbabs) Di Beberapa Kabupaten/kota Di Indonesia: Analisis Data Riskesdas 2007

Background: One of nutrition indicator is determined by good quality of human resource reflected by anthropometry such as body height. Objectives: The aim of th1s analysis is to measure the height of pre-elementary school children in rural and urban Indonesia. Methods: Data source of this analysis is Riskesdas Data (2007). Analytic unit of this study was house hold who had new prelimenary school children. (6-7 years old). Variable which was anthropometry data, height for age and sex, was analysed using software anthropometry plus WHO 2007 as standard reference. Other variables were social economic, head of family's job, living place (rural or urban) and income expenditure per-capita (kuintil). Results: This result shows that prevalence of pre-elementary school children having stunted is 28.4%. Whereas having normal height standard (WHO 2007) is 90.4%. There is no significant difference between boys and girls' height. However, children's height in rural and urban are different signicantly. More short pre-elementary students are found in rural than urban area. No significant relationship is found beetwen house hold social economic status and children's height. Conclusions: Prevalence of pre-elementary school children having stunted is 28.4%. More short pre-elementary students are found in rural than urban area

Antioxidative Defense Responses to lead-induced Oxidative Stress in Glycine max L. CV. Merrill grown in Different pH Gradient

Physiological and biochemical changes as well as the activities of anti-oxidative enzymes under lead (Pb2+) phytotoxicity were investigated in 20 days old soybean (Glycine max L.) seedlings grown hydroponically in the laboratory under different pH conditions. The rapid uptake of Pb 2+ was observed immediately after the start of treatment. The quantity of accumulation of Pb2+ was much higher in roots than in shoots, its level rising with increasing pH from 3.0 to 8.0 . Not only that, an oxidative stress conditions were observed due to increased level of superoxide anion radical and hydrogen peroxide in shoots and root cells of 20 days old seedlings when treated with Pb(NO3)2 at a concentration of 0, 500, 1000 and 2000 μM. Spectrometric assays of seedlings showed increased level of activities of antioxidant enzymes like catalase, peroxidase and glutathione reductase. The presence of thiobarbituric acid reacting substances (TBARS) indicates the enhanced lipid peroxidation compared to controls. The alteration in the activities of the antioxidant enzymes and the induction of lipid peroxidation reflects the presence of Pb2+, which may cause oxidative stress

Reactive Flow Simulation of Micromixers Based On Grid Deformation Techniques

Process intensification of engineering applications in the framework of reacting flows in micromixer devices attracts the attention of engineers and scientists from various fields. With the steadily increasing available computational resources the traditional experimentally supported investigations may be extended by computational ones. For this purpose, a simulation framework based on state of the art numerical techniques extended with special grid deformation techniques has been developed. Its validation in terms of comparison with computational and experimental results in reacting, as well as in non-reacting frameworks has been performed on the basis of the T-mixer, and SuperFocus mixer, respectively. The computational efficiency of the developed tool is shown to be applicable for optimization tasks, such as reverse engineering purposes

Effect of Electron Beam Irradiation and Storage on the Quality Attributes of Sausages with Different Fat Contents

Sausages with different fat contents (16 or 29%) were purchased from local stores, vacuum-packaged in oxygen-impermeable bags, and irradiated at 0 or 5 kGy using a linear accelerator. The changes in quality attributes of irradiated sausages were determined during storage at 4°C. The 2-thiobarbituric acid-reactive substance values of sausages were not affected by fat content but were increased after irradiation (5 kGy). Storage for 60 d increased the 2-thiobarbituric acid-reactive substance values of nonirradiated sausages (P \u3c 0.05) but had no effect on irradiated sausages. The numbers of volatile compounds and the amounts of total volatiles were increased by irradiation in both the high-fat (29% fat) and low-fat (16% fat) sausages. Dimethyl sulfide was detected only in irradiated sausages, regardless of fat content (P \u3c 0.05), but it disappeared after 60 d of storage. Pentane and 1-heptene were detected only in irradiated samples after 60 d of storage. Low-fat sausages had greater L* values, but had lesser a* and b* values than high-fat sausages. Irradiation and storage had little effect on either the exterior or interior color (L*, a*, and b* values) of sausages. Fat content had no effect on the sensory variables of sausages, regardless of irradiation and storage. However, irradiated sausages had significantly stronger off-odors and off-flavors than nonirradiated sausages regardless of fat content (P \u3c 0.05). This indicated that fat content in sausages had a minimal effect on the quality of irradiated sausages during storage

Antioxidant properties of tropical juices and their effects on in vitro hemoglobin and low density lipoprotein (LDL) oxidations

Antioxidant properties of tropical juices, namely bambangan (Mangifera pajang), cocoa (Theobroma cacao) pulp and guava (Psidium guajava) juices and their effects on in vitro hemoglobin and low density lipoprotein (LDL) oxidations were determined. Total phenolics and its compounds in selected juices were determined using Folin-Ciocalteu assay and high performance liquid chromatography (HPLC), respectively. Evaluation of antioxidant properties was done using in vitro assays namely as diphenyl-1-picrylhydrazyl (DPPH) scavenging, β-carotene bleaching (BCB), hemoglobin and LDL oxidation assays. Guava and bambangan juices had the highest and lowest of total phenolic content (TPC), respectively. Nevertheless, bambangan juice showed the greatest scavenging activity on DPPH radical. Furthermore, antioxidant activity (AA) in BCB assay was in the order of cocoa pulp (79%) > bambangan (76%) > guava (47%) juices. Interestingly, the highest inhibition of malondialdehyde (MDA) formation was exhibited by bambangan juice (0.31 µM MDA) in hemoglobin oxidation, while guava juice (0.27 µM MDA) in LDL oxidation systems. The study indicated that bambangan juice may have a potential to be introduced as functional foods product because of its antioxidant propertie