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[en] In the modern construction, fire safety has significant consideration for the protection of people and assets. Several intumescent fire protection systems are in practice and have constrain of releasing toxic gases on degradation forms an insulating char layer protecting underlying substrate. An intumescent coating expands many times of its thickness on exposure to fire and protect the underlying substrate from fire. This study presents the results of thermal performance of an intumescent fire retardant coating (IFRC) developed for structural application. IFRC was developed using expandable graphite (EG), ammonium poly phosphate (APP) and melamine (MEL), epoxy resin Bisphenol-A (BPA) and hardener triethylenetetramine (TETA) were used as a binder as a curing agent. Char expansion of IFRC was measured by furnace fire test at 450 degree C, thermal performance was measured using a Bunsen burner at 950 degree C and temperature of substrate was recorded for 60 min at an interval of two min. Results showed that IFRC containing 3wt% alumina showed char expansion X19. After one hour exposure of coating to heat, substrate temperature recorded was 154 degree C. X-ray Diffraction (XRD) results showed the presence of high temperature compounds present in the char of coating, considered responsible to reduce the penetration of heat to the substrate. (author)
[en] Yield response of potato to planned water stress was studied in field experiments conducted during 1990-95. There were seven irrigation treatments comprising water stress and nonstress periods imposed at four growth stages. Each irrigation treatment was split into two fertilizer treatments where optimal and suboptimal fertilization levels were applied. The results obtained showed that the timing of water stress influenced the tuber yield differently. The stress imposed at ripening stage caused least reduction in yield whereas that imposed at early development followed by tuber formation stage the greatest reduction. A plot of relative yield reduction versus relative water use deficit revealed that the most sensitive period of growth to water stress, hence most responsive to irrigation, was early development compared to tuber formation and flowering. The traditional irrigation practice led to wasteful water applications. The efficiency of water use was increased by applying deficit irrigation at appropriate growth stages with no adverse effect on yield. The studies with 15N-labelled fertilizer showed that planting and earthing-up were equally important growth stages for applying N-fertilizer for its efficient utilization. (author). 16 refs, 1 fig., 5 tabs
[en] The responses of three cropping sequences to two tillage and nutrient-management factors with a view to improved and sustained productivity of a rainfed farming system were tested at the Nuclear Institute for Food and Agriculture (NIFA) Research Station and farmers' fields from 1998 to 2002. The tillage treatment improved grain yield of wheat at the research station, but did not improve farmers' yields significantly. Fertilizer-N utilization by wheat was greater on farmers' fields (up to 42% of applied N) than at the research station (up to 33%). Grain yield of lentil was not influenced by tillage or nutrient level, but N accumulation in grain was significantly greater at the higher P level. Nitrogen fixation was also stimulated by higher P. The lentil crop obtained 82 to 96% of its N from fixation, up to 6% from applied fertilizer and up to 12% from soil. The amounts fixed varied from 42 to 91 kg/ha in different treatments. The chickpea crop obtained 52 to 64% of its N from fixation, up to 9% from applied fertilizer and up to 39% from soil. Carbon-13 discrimination values (δ) of straw, grain and root of wheat revealed no evidence of water stress at NIFA under tillage. On a farmer's field at Urmar, tillage induced some water deficit as reflected by less-negative δ values of straw. Applied P had no significant effect on moisture availability. Intercropping of wheat, lentil and chickpea was not productive. Lentil, a legume, had a significant positive effect on yield of subsequent wheat as compared to a wheat-wheat sequence, potentially providing additional income. The %N derived from fertilizer and %N utilization from residual 15N-labelled urea indicated that wheat utilized less than 1% of the N applied in the previous year. Water-use efficiency (WUE) in terms of wheat grain was improved (3.31 kg ha-1 mm-1) in the lentil-wheat sequence and tillage treatment at NIFA as compared to no-tillage and wheat-wheat sequence. The WUE of wheat grain indicated a good correlation (R2=0.988) with δ13C values of grain. (author)
[en] In this work, a general two-point Ostrowski’s formula from an analytic point of view is presented. New triangle type inequalities for Riemann–Stieltjes integrals are established. Sharp two-point Ostrowski’s type inequalities for functions of bounded p-variation and functions satisfy Lipschitz condition involving -bounds are proved. Some sharp inequalities ramified from the presented inequalities are also obtained.
[en] In this work, inequalities of Beesack–Wirtinger type for absolutely continuous functions whose derivatives belong to spaces are proved. Generalizations of the results for n-times differentiable functions are established. Consequently, two Ostrowski and Čebyšev type inequalities for absolutely continuous functions whose derivatives belong to spaces are provided.
[en] We present a new approach for the two-temperature molecular dynamics (MD) model for coupled simulations of electronic and phonon heat conduction in nanoscale systems. The proposed method uses a master equation to perform heat conduction of the electronic temperature eschewing the need to use a basis set to evaluate operators. This characteristic allows us to seamlessly couple the electronic heat conduction model with MD codes without the need to introduce an auxiliary mesh. We implemented the methodology in the large-scale atomic/molecular massively parallel simulator code, and through multiple examples, we validated the methodology. We then study the effect of electron–phonon interaction in high energy irradiation simulations and the effect of laser pulse on metallic materials. We show that the model provides an atomic level description in complex geometries of energy transfer between electrons and phonons. Thus, the proposed approach provides an alternative way to the two-temperature MD models. The parallel performance and some aspects of the implementation are presented. (paper)
[en] A field experiment was conducted to study the effect of crop residues and tillage practices on BNF, WUE and yield of mungbean (Vigna radiata (L.) Wilczek) under semi arid rainfed conditions at the Livestock Research Station, Surezai, Peshawar in North West Frontier Province (NWFP) of Pakistan. The experiment comprised of two tillage i) conventional tillage (T1) and ii) no-tillage (T0) and two residues i) wheat crop residues retained (+) and ii) wheat crop residues removed (-) treatments. Basal doses of N at the rate of 20: P at the rate of 60 kg ha-1 were applied to mungbean at sowing time in the form of urea and single super phosphate respectively. Labelled urea having 5% 15N atom excess was applied at the rate of 20 kg N ha-1 as aqueous solution in micro plots (1m2) in each treatment plot to assess BNF by mungbean. Similarly, maize and sorghum were grown as reference crops and were fertilized with 15N labelled urea as aqueous solution having 1% 15N atom excess at the rate of 90 kg N ha/sup -1/. The results obtained showed that mungbean yield (grain/straw) and WUE were improved in notillage treatment as compared to tillage treatment. Maximum mungbean grain yield (1224 kg ha/sup -1/) and WUE (6.61kg ha/sup -1 mm/sup -1/) were obtained in no-tillage (+ residues) treatment. The N concentration in mungbean straw and grain was not significantly influenced by tillage or crop residue treatments. The amount of fertilizer-N taken up by straw and grain of mungbean was higher under no-tillage with residues-retained treatment but the differences were not significant. The major proportion of N (60.03 to 76.51%) was derived by mungbean crop from atmospheric N2 fixation, the remaining (19.6 to 35.91%) was taken up from the soil and a small proportion (3.89 to 5.89%) was derived from the applied fertilizer in different treatments. The maximum amount of N fixed by mungbean (82.59 kg ha/sup -1/) was derived in no-tillage with wheat residue-retained treatment. By using sorghum as reference crop, the biological nitrogen fixed by mungbean ranged from 37.00 to 82.59 kg ha/sup -1/ whereas with maize as a reference crop, it ranged from 34.74 to 70.78 kg ha/sup -1/ under different treatments. In comparison, non-fixing (reference) crops of sorghum and maize derived up to 16.6 and 15.5% of their nitrogen from the labelled fertilizer, respectively. These results suggested that crop productivity, BNF and WUE in the rainfed environment can be improved with minimum tillage and crop residues retention. (author)
[en] This contribution represents the manufacturing of a hybrid organic–inorganic proton conducting compound, which involves the introduction of heteropoly acid (HPA) of different concentrations into poly-vinyl alcohol (PVA). These compounds were irradiated by γ-rays at different doses of 10, 20, 30, and 40 kGy. The unirradiated and irradiated compounds were characterized by XRD and DSC. The XRD results showed that the crystallinity and d-spacing were strongly influenced by the amount of HPA and irradiation doses. The DSC results showed that the melting point was decreased as a result of HPA concentration and irradiation doses. The degree of crystallinity calculated from XRD is in good agreement with that calculated from DSC. The activation energy of the Unirradiated and irradiated compounds was calculated using the Flynn–Wall–Ozawa model. - Highlights: ► Keggin-structure compound immobilized in a polymeric matrix was prepared. ► These samples were subjected to different doses 10, 20, 30, and 40 kGy of γ-rays. ► The crystallinity and d-spacing were changed by HPA amount and irradiation doses. ► The melting point was decreased as a result of HPA amount and irradiation doses.
[en] The mass attenuation coefficients (μ/ρ) of a natural material, i.e., olive peat, were measured at photon energies of 0.059, 0.356, 0.662, 1.17, and 1.332 MeV and compared with those of concrete and Pb. The experimental samples were irradiated with 214Am, 133Ba, 137Cs, and 60Co point sources using a transmission arrangement. The olive peat samples were obtained from different areas in Jordan, namely Mafraq (sample M), Kerak (sample K), Ajloun (sample A), and Irbid (sample I), and photon energies were measured using a NaI(Tl) scintillation detector with an energy resolution of 7.6% at 662 keV. The differences in the µ/ρ of olive peat samples and the calculated µ/ρ of concrete were consistently within 0.7% at photon energies of 0.356–1.332 MeV. This finding indicates that olive peat can be used in radiation applications in the field of medical physics. Finally, the half-value layer (HVL) of the experimental samples was measured, and results were compared with those of concrete and Pb. Pb and concrete exhibited minimal HVL values due to their high density, and the HVL of olive peat revealed lower shielding effectiveness than that of concrete.