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991.
Megh Singh J. R. Orsenigo D. O. Shah 《Journal of the American Oil Chemists' Society》1984,61(3):596-600
Contact angle and surface tension were measured for distilled and hard water solutions of adjuvants, Ortho X-77, Span-20,
Sterox-NJ. Surfactant-WK, Triton B-1956, Triton X-114, Tween-20, and Sun Oil 11E. The same parameters were measured for suspensions
of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] and ametryne [2-(ethylamino)-4-(isopropylamino)-6-(methylthio)-s-triazine] with and without each adjuvant. All adjuvants reduced surface tension and contact angle of distilled water; Surfactant-WK
was most effective and Tween-20 was least effective. Increasing concentration of surfactants from 0 to 0.1% (v/v) gave progressive
reduction in surface tension and contact angle while higher concentrations, 0.1 to 2.0% (v/v), had no further effect. Surfactant-WK
at 0.1% (v/v) in distilled water reduced the surfact tension from 72.8 dynes/cm to 27 dynes/cm and contact angle from 110°
to 41°. An additional increase in Surfactant-WK concentration from 0.1% (v/v) to 2% (v/v) did not further reduce surface tension
and contact angle. Sun Oil 11E was identical in behavior except that it was less effective than the surfactants. Water hardness
up to 1,000 ppm as Ca ions did not affect surface tension and contact angle in surfactant solutions. An aqueous solution of
atrazine had a higher surface tension and contact angle than ametryne in the absence of surfactants. However, these differences
were not observed when surfactants were added to either herbicide. 相似文献
992.
Thermal stability of PVC blends with chlororubber-20-graft polyblend-styrene-acrylonitrile [CR-20gp-SAN (2:1)] was studied by HCI evolution techniques and thermogravimetry under isothermal condition. The thermal stability of PVC/CR-20gp-SAN (2:1) blends has been compared with those of PVC/CR-20 and PVC/KM-365B blends. It has been observed that the thermal stability of modified PVC is less than that of unmodified PVC. The CR-20gp-SAN (2:1) modified PVC blends were found to be more stable than PVC/CR-20 blends but less stable than PVC/KM-365B blends. The rate of degradation in PVC blends were observed to be unaffected by the concentration of the modifiers, but the PVC/KM-365B blends were found to be degrading slower in comparison with PVC/CR-20 and PVC/CR-20gp-SAN (2:1) blends. The rate of degradation for PVC/CR-20 blends at lower concentrations (<10%) of modifiers is almost equal to that of PVC/CR-20-gp-SAN (2:1) blends, but more at higher concentrations of modifiers (>10%). The experimental results have been explained on the basis of the chemical nature of the modifiers and their miscibility with PVC. 相似文献
993.
An empirical correlation between reduced viscosity and reduced temperature for molten salt hydrates showing Arrhenius behavior above their melting points has been reported. This correlation predicts the viscosity of molten salt hydrates at temperatures not more than 15 to 30°C above the melting points, within an accuracy of ±5%. Consistency tests for viscosity data using reduced parameters have been reported. 相似文献
994.
N.B. Singh 《Cement and Concrete Research》1976,6(3):409-412
Structure and reactivity of solid solutions of C3S doped with NiO have been studied using x-ray, DTA, I.R. spectroscopy and isothermal microcalorimetry. I.R. spectra and free lime determinations show that probably Ni substitutes for Ca. Differential thermal analysis shows that NiO changes the transition temperatures of C3S. Calorimetric studies indicate that hydration of C3S is accelerated in presence of NiO. Electrical conductivities of the samples were also measured in the solid state in the temperature range of 800–1000°C. It is pointed out that solid solutions are electronic conductors. 相似文献
995.
Prices of fuels such as coal and diesel are showing uptrend continuously in India due to which the manufacturing sector is finding it hard to control the production cost. The manufacturing units are emphasising upon innovative practices to reduce the electrical energy consumption in order to reduce production cost. They are recognising renewable energy as one of the options to save fuel cost to some extent by running some partial load on this energy. This paper is presenting a technical and economic analysis for proposing a hybrid renewable energy system, comprising Solar Photovoltaic, wind, a storage battery and a diesel unit, for running auxiliary load of a cement manufacturing unit located in Durg district of Chhattisgarh, India. As the diesel prices are continuously increasing almost rupees 0.5 per month in India for the last few months, the diesel price sensitivity analysis is also done for optimal system sizing. The results show that diesel price increment from $1.01 to $1.09 does not affect optimal system size but only net present cost and levelised cost of energy. When diesel price increases beyond $1.09, the optimal system size increases resulting in capital cost increment. It attains a new optimal system size at a diesel price of $1.13. 相似文献
996.
Surface runoff estimation over heterogeneous foothills of Aravalli mountain using medium resolution remote sensing rainfall data with soil conservation system‐curve number method: A case of semi‐arid ungauged Manesar Nala watershed 下载免费PDF全文
Manesar Nala watershed, having an aerial extent of 71.53 km2, was subjected to modelling of its hydrological behaviour for assessing its water resource potential. Modern tools and techniques of Remote Sensing (RS) and Geographic Information System (GIS) were used for assessment of runoff generating potential using the Hydrologic Soil Cover Complex (HSCC) Method [U.S. Department of Agriculture (USDA)‐Soil Conservation System‐Curve Number (SCS‐CN) approach]. RS and GIS were used in generation and integration of thematic maps [such as Land use/Land cover (using LISS‐III data) and Hydrologic Soil Group (HSG), (using soil map of study area) to derive the Curve Number (CN) for simulating Runoff (Ro)]. The daily rainfall (P) data for the study period 2002–2015 were acquired from NOAA Climate Prediction Center (NCPC). Corresponding Ro from the watershed for intense storm events for 14 years were calculated through RS and GIS. GIS and SCS‐CN model was employed for modelling the runoff production to study its hydrological behaviour. The study showed that the Manesar Nala watershed was having a composite Curve Number – II (CNII) value of 82.5 for normal conditions. For dry and wet conditions these values were estimated at 66.44 (CNI) and 91.56 (CNIII), respectively. This investigation showed that Manesar Nala watershed exhibited an annual average (of 14 years, 2002–2015) Ro volume of 4 542 514.37 m3 based on the average annual rainfall (P) of 0.72 m (720 mm). The average annual surface runoff (Ro) was predicted to be approximately 0.21 m with annual runoff coefficient (CR) of 0.29. During the study, we also found a strong correlation ‘r’ between satellite driven P and Ro from NRCS‐CN method of the order of 0.94. The methodology so developed has the potential to be used in other similar ungauged watersheds in the same agro‐climatic conditions for the purpose of planning of watershed conservation measures and other developmental activities. 相似文献
997.
Estimation of greenhouse gas emissions from municipal wastewater treatment systems in India 下载免费PDF全文
Greenhouse gas (GHG) emissions generated from municipal wastewater treatment plants in India is estimated in this study. The emissions from the wastewater treatment process as well as from the electricity used during the treatment process are estimated by using the methodology of Intergovernmental Panel on Climate Change. The present treatment plants of capacity 15 997 million litres per day (MLD) contributes towards GHG emissions of 7.3 Mt of CO2‐eq/year. The future GHG emissions would depend upon the treatment technology used for treating 34 109 MLD of untreated wastewater. The highest GHG emissions would occur if all new wastewater treatment plants are based on upflow anaerobic sludge blanket technology, 19.66 Mt CO2‐eq/year and lowest if sequential batch reactor technology is adopted, 2.93 MtCO2‐eq/year. 相似文献
998.
Forest fire is an serious hazard in many places around the world. For such threats, video-based smoke detection would be particularly important for early warning because smoke arises in any forest fire and can be seen from a long distance. This paper presents a novel and robust approach for smoke detection that employs Deep Belief Networks. The proposed method is divided into three phases. In the preprocessing phase, the region of high motion is extracted by background subtraction method. During the next phase, smoke pixel intensities are extracted from the Red, Green and Blue and Luminance; Chroma:Blue; Chroma:Red color spaces for foreground regions. Subsequently, second feature which is based on texture is computed for detecting smoke regions in which Local Extrema Co-occurrence Pattern, an improved version of local binary patterns are extracted from different foreground regions which compute not only texture of smoke but also intensity and color of smoke using Hue Saturation Value color space. Finally, Deep Belief Network is employed for classification. The proposed method proves its accuracy and robustness when tested on different varieties of scenarios whether wildfire-smoke video, hill base smoke video, indoor or outdoor smoke videos. 相似文献
999.
In this paper, the absorption spectra of multilayer structures have been obtained and analysed in the wavelength range 0.5–10 μm. The multilayer system is an SMS type in which M is a thin metallic layer sandwiched between two semiconducting layers. The systems (i) B.S./Cu/B.S. and (ii) Cu2S/Cu/Cu2S (where B.S. = black sulphide) are developed by the methods of electrodeposition/chemical dipping, whereas the ZnS/Cu/ZnS system is fabricated in vacuo. The /ε ratios are also calculated using the experimentally observed absorption spectra, and found to be higher in the case of the ZnS/Cu/ZnS system, in comparison to the other two systems. The absorption spectra have also been calculated using our theoretical model of the above-mentioned systems. 相似文献
1000.
A Simple Conceptual Model of Sediment Yield 总被引:2,自引:0,他引:2
Pradeep Kumar Bhunya S. K. Jain P. K. Singh S. K. Mishra 《Water Resources Management》2010,24(8):1697-1716
The sediment graphs (time distribution of sediment yield) are very essential if the sediment transports the pollutants that
are toxic at high concentrations, requiring determination of peak, rather than average sediment flow rate. In this paper,
an effort has been made to develop a simple conceptual model of sediment yield based on Soil Conservation Service Curve Number
(SCS-CN) method, instantaneous unit sediment graph (IUSG) method, and Power law and the performance is tested using real field
data of Chaukhutia watershed of Ramganga river catchment (area = 452.25 km2). The proposed model is found to provide realistic estimates of temporal variation of sediment yield as well as total sediment
yield during a storm event. The model is found to be most sensitive to parameter β followed by k,
\upalpha\upalpha, A, and ns. A comparison is made with the existing IUSG based models of Kumar and Rastogi (J Hydrol 95:155–163, 1987) and Raghuwanshi et al. (J Hydraul Eng ASCE 120(4):495–503, 1994) for developing sediment graphs. 相似文献