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Kore Ekanath K. Shahane Guruling S. Mulik Ramesh N. 《Journal of Materials Science: Materials in Electronics》2022,33(13):9815-9829
Journal of Materials Science: Materials in Electronics - The Co1?xZnxFe2O4 (Co–Zn) ferrite nanoparticles with x varying from 0.0 to 0.4 have been manufactured by facile chemical... 相似文献
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M T Zaranski G W Patton L L McConnell T F Bidleman J D Mulik 《Analytical chemistry》1991,63(13):1228-1232
Glass cartridges containing 6-10 g of Tenax-GC or 15 g of XAD-2 resin packed between two slices of polyurethane foam (PUF) were used in a General Metal Works PS-1 high-volume sampler to collect chlorobenzenes (CBs) containing three to six chlorine atoms, hexachlorocyclohexanes (HCHs), and two-ring aromatic hydrocarbons from 35-385 m3 of air. Laboratory experiments were run by vaporizing known quantities of analytes into a clean airstream for sampling by the PS-1 system at 20 degrees C. Collection efficiencies, determined from mass balance of the quantities introduced and recovered, ranged from 70 to 120% for individual compounds and averaged 93% overall. Penetration of analytes to backup adsorbent traps showed an inverse correlation to vapor pressure. The method was used to collect the above compounds from urban and rural air. 相似文献
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The wear and friction properties of poly (ether‐ether‐ketone) (PEEK) reinforced with 0–33 vol % (60 wt %) micron size Al2O3 composites were evaluated at a sliding speed of 1.0 m/s and nominal pressure from 0.5 to 1.25 MPa under dry sliding conditions using a pin‐on‐disk wear tester. The wear resistance of the pure PEEK is 10‐fold higher than that of mild steel under the similar test condition. It is improved to 18‐fold as compared with mild steel at 3.5 vol % Al2O3 content. The improvement in wear properties may be attributed to the thin, tenacious, and coherent transfer film formed between the steel countersurface and composite pin. However, the wear resistance of PEEK containing above 3.5 vol % Al2O3 was deteriorated, despite their higher hardness and stiffness as compared with that of composites containing lower Al2O3 content. This is attributed to the formation of thick and noncoherent transfer film, which does not prevent the wear of the composites from hard asperities of countersurface. Moreover, hard Al2O3 particles present in transfer film act as third body wear mechanism. The coefficient of friction of the composites is higher than that of pure PEEK. SEM and optical microscopy have shown that wear of pure PEEK occurs by the mechanism of adhesion mainly whereas of PEEK composites by microploughing and abrasion. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
4.
P.Richard Mulik 《Fuel》1984,63(12):1731-1737
The testing of 18 alternative fuels was the basis for an extensive data bank of combustion parameters and fuel properties. This Paper represents an effort to correlate the three key dependent variables (NOx, smoke, and wall temperature) to the process conditions and fuel properties. Correlation was facilitated by the use of a multiple linear regression computer program. Linear terms, second-order terms, and their interactions were investigated. Correlation development is discussed and the results presented. Determining the physical meaning of the correlations is attempted together with a discussion concerning extrapolation of the correlations over the range of current operational gas turbine combustors. The correlations can be described as excellent for NOx and good-to-fair for smoke and wall temperature. 相似文献
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Parag V. Adhyapak Uttam P. Mulik Dinesh P. Amalnerkar Imtiaz S. Mulla 《Journal of the American Ceramic Society》2013,96(3):731-735
In this study, we report template and surfactant‐free, low temperature (70°C) synthesis of needle‐like α‐FeOOH and its conversion at 400°C into α‐Fe2O3 nanorods using Fe(+2) and Fe(+3) chlorides and urea as a hydrolysis‐controlling agent. The isolated needle‐like α‐FeOOH indicates asparagus‐type growth pattern having length ca. 600 nm with 80 nm diameter at base and apex diameter of around 10 nm. The sample on heating (α‐Fe2O3) shows nanorod‐like morphology. The samples were characterized using various physicochemical characterization techniques such as XRD, Raman spectroscopy, UV‐Vis spectroscopy, particle size distribution analysis, Field Emission Scanning Electron Microscopy (FE‐SEM), and humidity sensing performance. The humidity sensing behavior of both α‐FeOOH and α‐Fe2O3 was studied. The α‐FeOOH shows quicker (10 s) and higher response toward change in humidity from 20%RH to 90%RH as compared with α‐Fe2O3 (60 s). Their typical morphology and crystalline structure plays an important role in humidity sensing behavior. 相似文献
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S. V. Sujith Manas Mohan Mahapatra Rahul S. Mulik 《Transactions of the Indian Institute of Metals》2018,71(4):923-934
Automobile and aerospace industries use thin wall aluminium alloy castings which provide lighter structures with excellent mechanical properties. Production of thin wall castings is more challenging due to hot tear formation. Lack of fluidity in molten alloy causes hot tears and must be addressed in thin wall castings of Al-alloys. The present study is focused on a new technique known as stepped ring mould casting. It is possible to assess the hot tear susceptibility of Al–6Zn alloys by varying ring thickness to find out the critical thickness for occurrence of hot tears. The alloy was cast using different strontium (Sr) concentrations (0.2, 0.4, 0.6%). Effects of strontium concentrations were studied in terms of fluidity, porosity content, microstructure and tensile properties of Al–6Zn alloy. In the present work, unmodified and Sr modified alloy casts were characterized by SEM, EDS and XRD respectively. Al–6Zn ingots were procured by master alloy route. Repetition of stepped ring test on the critical thickness showed that hot tear were successfully eliminated significantly due to the addition of Sr. On the other hand, 0.6% Sr also exhibited a good amount of porosity and decrease in elongation. Shorter fluidity length was observed in 0.2% Sr modified alloy. Mechanical and metallographic tests revealed that the alloy castings modified with 0.4% Sr offered better results in yield strength, less porosity and an improved hot tear resistance at micro and macro levels. 相似文献
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G.D. Khuspe R.D. Sakhare S.T. Navale M.A. Chougule Y.D. Kolekar R.N. Mulik R.C. Pawar C.S. Lee V.B. Patil 《Ceramics International》2013,39(8):8673-8679
We report the synthesis of nanostructured SnO2 by a simple inexpensive sol–gel spin coating method using m-cresol as a solvent. This method facilitates rapid synthesis at comparatively lower temperature enabling formation of nanostructures suitable for gas-sensing applications. Various physicochemical techniques have been used for the characterization of SnO2 thin films. X-ray diffraction analysis confirmed the single-phase formation of tetragonal SnO2 having crystallite size 5–10 nm. SnO2 showed highest response (19%) with 77.90% stability toward 100 ppm nitrogen dioxide (NO2) at 200 °C. The response time of 7 s and recovery time of 20 min were also observed with the same operating parameters. The probable mechanism is proposed to explain the selective response toward nitrogen dioxide. Impedance spectroscopy studies showed that the response to nitrogen dioxide is mainly contributed by grain boundaries. The reproducibility and stability study of SnO2 sensor confirmed its candidature for detection of NO2 gas at low concentration (10–100 ppm) and lower operating temperature. 相似文献
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Parag Adhyapak Poonam Mahapure Rohini Aiyer Suresh Gosavi Uttamrao Mulik Dinesh Amalnerkar 《应用聚合物科学杂志》2012,123(6):3565-3574
Cobalt (Co) nanoparticles (with different loadings, 1 and 2 wt %, of Co) were synthesized in situ in a poly(vinyl alcohol) (PVA) matrix with and without meta‐nitroaniline (m‐NA) as a dopant (2.5 wt %). The obtained nanocomposite films were characterized with various physicochemical techniques, including ultraviolet–visible spectrophotometry, X‐ray diffraction analysis, scanning electron microscopy, and Fourier transform infrared analysis. To study the effect of the humidity, the nanocomposite solutions were coated on planar glass substrates. The beam of an He–Ne laser was incident normal to the film surface and was subjected to variable relative humidities (RHs; 4–93%); the transmitted intensity was measured on a photovoltaic diode. Variations in the intensity of light caused by the changes in RH within the range 3–93% were recorded. We optimized the response by varying the film thickness by coating the solution layer by layer. We generated the RH (4–100%) by passing wet water vapors. The neat PVA film of similar thickness gave humidity sensing in the range 78–93% RH. The sensors with m‐NA‐doped Co/PVA gave better sensitivity (6.4 mV/% RH) than the undoped samples (1.78–2.45 mV/% RH), exhibiting a fast response of 3 s (2–93% RH) and a recovery of 10 s (93 to 2% RH). These samples also showed reversible behavior and long‐term stability (for nearly a year) with a good sensitivity and a large dynamic range (2–95% RH). An attempt was made to explain the results on the basis of a bulk mechanism. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献