Showing papers by "Aligarh Muslim University published in 1986"
01 Apr 1986-Precision Engineering-journal of The International Societies for Precision Engineering and Nanotechnology
TL;DR: In this article, an analysis for the computation of the plasma channel size was presented as a function of pulse-on-duration (POND) in edm machined workpieces and the analytical values of the resolidified layer thickness agreed well with published experimental data.
Abstract: An analysis for the computation of the plasma channel size, is presented as a function of pulse-on duration in edm . It has been shown that accounting for the effects of the plasma growth leads to marked improvement in analytical results obtained. The paper also suggests a method for evaluating the thickness of the resolidified layer in edm machined workpieces. The analytical values of the resolidified layer thickness agree well with published experimental data.
112 citations
TL;DR: In this paper, the nature of galactic cosmic ray transient modulation associated with three types of interplanetary magnetic clouds - clouds associated with shocks, stream interfaces and cold magnetic enhancements -was analyzed.
Abstract: Neutron monitor data has been analyzed to study the nature of galactic cosmic ray transient modulation associated with three types of interplanetary magnetic clouds - clouds associated with shocks, stream interfaces and cold magnetic enhancements.
86 citations
TL;DR: Pallidol, a new 3,5,4′-trihydroxystilbene dimer, isolated from the stemwood of Cissus pallida is assigned the structure 5,11 p -hydroxyphenyl-2,4,8,10-tetrahydroxydibenzo[a,e]tetrahedropentalene on the basis of spectral evidence.
82 citations
TL;DR: A clinical survey of 500 patients revealed 4.2% incidence of Arnold's ear-cough reflex, and the reflex was bilateral in 2.8% of the patients, thus questioning the classically taught distribution of Schwarzenegger's nerve.
Abstract: A clinical survey of 500 patients revealed 4.2% incidence of Arnold's ear-cough reflex. The reflex was bilateral in 2.8% of the patients. It was also elicitable from the anterior meatal wall in 2% of the patients, thus questioning the classically taught distribution of Arnold's nerve. Arnold's nerve also mediates the auriculo-palatal auriculo-lacrimal, auriculo-cardiac and the ear-vomiting reflexes; but these are less apparent and not so commonly encountered.
64 citations
TL;DR: A hot water extract of C. chinensis markedly delayed the appearance and retarded the growth of papillomas and the incidence of carcinoma in Swiss albino mice, and its prophylactic effect was found to be statistically significant.
50 citations
TL;DR: In this paper, a capacitance multiplier circuit, using operational transconductance amplifiers, is realized, which provides widerange linear control of the capacitance value with direct voltage or current.
Abstract: A capacitance multiplier circuit, using operational transconductance amplifiers, is realised. The circuit provides widerange linear control of the capacitance value with direct voltage or current. This makes the realisation of large-valued grounded capacitors possible in IC fabrication. The linearly tunable capacitor is expected to find attractive applications in voltage/current-controlled filters, oscillators etc.
44 citations
TL;DR: The results suggest that the initial interaction of quercetin with DNA may have a stabilizing effect on its secondary structure, but prolonged treatment leads to an extensive disruption of the double helix.
Abstract: I n vitro experiments to study interaction of the mutagenic flavonoid quercetin with DNA are described. Calf thymus DNA treated with quercetin for various time periods was subjected to S1 nuclease hydrolysis. Thermal melting profles of treated DNA were also determined using St nuclease. The rate of DNA hydrolyzed after 1 hr of pre-treatment with quercetin was found to be only about 50% of that in its absence. However, after 10 and 24hrs of treatment with the drug, the rate of S1 nuclease hydrolysis was observed to be greater than that of native DNA. Thermal melting profiles of DNA, treated with quercetin for 10 and 24 hrs, indicated a slight decrease in melting temperatures. Gel filtration of native DNA, which had been digested with S1 nuclease after preincubation with quercetin for 24 hrs, indicated the production of various sized degraded molecules. The results suggest that the initial interaction of quercetin with DNA may have a stabilizing effect on its secondary structure, but prolonged treatment leads to an extensive disruption of the double helix.
38 citations
TL;DR: In this article, a new computer equation is used for the psychrometric properties of air, based on the observation that the cooling effect of product desiccation is significant during the initial stages but becomes negligible later.
Abstract: A calculation scheme has previously been reported for predicting air blast cooling of spherical food products. This was based on the observation that the cooling effect of product desiccation is significant during the initial stages but becomes negligible later. This work was extended so that the calculation scheme can also be used for cylindrical products. A new computer equation is used for the psychrometric properties of air.
28 citations
TL;DR: In this article, simple circuits using only two operational transeonductance amplifiers are given for the simulation of positive and negative resistors, which are electronically tunable over several decades with bias voltage/current control.
Abstract: Simple circuits using only two operational transeonductance amplifiers are given for the simulation of positive and negative resistors. The component values of these resistors are electronically tunable over several decades with bias voltage/current control. This makes the simulators very attractive for use in integrated circuits.
26 citations
TL;DR: In this paper, a new and simple technique for capacitance measurement is presented, which uses a dc supply, and capacitance is measured using a single resistance variation, and experimental results confirm the theory developed.
Abstract: A new and simple technique for capacitance measurement is presented. It uses a dc supply, and capacitance is measured using a single resistance variation. Experimental results confirm the theory developed.
26 citations
TL;DR: In this article, macaflavones I and II, isolated from the leaves of Macaranga indica, have been characterized as 6,7,2,2-dimethylchromeno-8,γ,γ-dimmethylallyl-3,3′,4′-trihydroxyflavone and 6.7, 2, 2-dimethyltimethylchromoeno-8.
TL;DR: Chromatographic separation of the acetone extract of Lannea acida leaves resulted in the separation of a new flavanone, 6,7,2,2-dimethylchromeno-8γ,γdimethylallyl flavanones.
TL;DR: For homogeneous spherical produce numerically generated time-temperature data are used to develop a relationship between the Fourier number, Biot number, dimensionless radial distance and normalized temperature as discussed by the authors.
Abstract: For homogeneous spherical produce numerically generated time-temperature data are used to develop a relationship between the Fourier number, Biot number, dimensionless radial distance and normalized temperature. This allows determination of thermal diffusivity through time-temperature measurements. The method is used to determine the thermal diffusivity of apples, oranges and portatoes. The results are compared with those from previous studies 1,2 , and good agreement is observed.
01 Jan 1986-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this article, a beam of alpha-particles of energy ≈ 40 MeV has been made to bombard a stack of ten gold foils, which were selected so as to obtain an energy degradation of the order of 2 to 4 MeV.
Abstract: The stacked foil technique has been used to measure the excitation functions for the reactions 197Au(α, xn), x = 1 to 3. A beam of alpha-particles of energy ≈ 40 MeV has been made to bombard a stack of ten gold foils. The thickness of the gold foils was selected so as to obtain an energy degradation of the order of 2 to 4 MeV. The induced activities in each foil were followed using a HPGe system. Theoretical excitation functions for these reactions based on the equilibrium decay model do not agree, in general, with the measured ones towards the high energy tails. Excitation functions have also been calculated simulating the pre-equilibrium emission by a hybrid model. The experimental excitation functions are best reproduced by taking a mixture of both the equilibrium and pre-equilibrium emissions.
TL;DR: The crosslinked concanavalin A-amyloglucosidase preparations were, however, only slightly more stable against thermal denaturation than the soluble enzyme.
TL;DR: Considerable variations of trichome type, frequency and distribution were observed on both the leaf surfaces of S. melongena grown near the Thermal Power Plant Complex of Kasimpur, West Uttar Pradesh, India.
TL;DR: Sterculia foetida methyl esters were used as a reference standard in this paper to establish the co-occurrence of these two acids in seed oils of Gnetum scandens and Sterculia pattens.
Abstract: Seed oils ofGnetum scandens (Gnetaceae) andSterculia pattens (Sterculiaceae) were found to contain sterculic (28.57,6.97) and malvalic (11.27,3.87) acids, respectively. Gas Chromatographic analysis of silver nitrate/meth-anol-treated methyl esters was used to establish the co-occurrence of these two acids.Sterculia foetida methyl esters were used as a reference standard.
TL;DR: In this paper, the kinetics of the reaction of hexaaquachromium(III) ion with aspartic acid in aqueous acidic medium have been investigated spectrophotometrically at [H+]=1×10−4 − 10× 10−4mol dm−3, t=35-45 °C and μ=1.0 mol dm −3 (KNO3).
Abstract: The kinetics of the reaction of hexaaquachromium(III) ion with aspartic acid in aqueous-acidic medium have been investigated spectrophotometrically at [H+]=1×10−4 – 10× 10−4mol dm−3, t=35–45 °C and μ=1.0 mol dm−3 (KNO3). The results are in accord with a mechanism involving a fast 1∶1 outer-sphere association between hexaaquachromium(III) ion and the substrate species, followed by their transformation into the product by the process where the incoming ligand is appreciably bounded to the metal ion in the transition state. The rate law consistant with the mechanism is as follows:
$$\begin{gathered} k_{obs} = \frac{{\left( {k_1 K_{IP} K_2 + k_2 K'_{IP} \left[ {H^ + } \right]} \right)\left[ A \right]_T }}{{\left( {{{\left[ {H^ + } \right]^2 } \mathord{\left/ {\vphantom {{\left[ {H^ + } \right]^2 } {K_1 }}} \right. \kern-
ulldelimiterspace} {K_1 }}} \right) + \left[ {H^ + } \right] + K_2 + \left( {K_{IP} K_2 + K'_{IP} \left[ {H^ + } \right]} \right)\left[ A \right]_T }} \hfill \\ A = Aspartic acid \hfill \\ \end{gathered} $$
The rate parameters were evaluated and associated activation parameters calculated using the Eyring equation. Enthalpy and entropy terms for the rate constants:viz. ΔH≠(k1)=+81±1 kJ mol−1, ΔH≠(k2)=+50±1 and ΔS≠(k1)=−54±3 JK−1 mol−1, ΔS≠(k2)=−157±2 JK−1 mol−1 are indicative of an (Ia) mechanism. Comparison of the results with published data on this metal ion also provide evidence of an associative interchange mechanism.
TL;DR: The adsorption thermodynamics of carbofuran has been studied on antimony (V) silicate cation exchanger at 30 and 50 degrees C and the adsorbed isotherms have been found to follow the Freundlich adsorptive model and yield "S" class isotherm.
TL;DR: The cambial cells vary considerably in size and number with the girth of stem axis in Holoptelen integrifolia, and the proportion of fusiform initials exhibits an almost gradual decrease with the age of the meristem.
TL;DR: Two types of frontal glands, cortical and medullary, have been observed in the scolex parenchyma of Tentacularia coryphaenae Bosc 1802 and their structure, position, mode of secretion and possible functions have been elucidated through standard histochemical techniques.
Abstract: Two types of frontal glands, cortical and medullary, have been observed in the scolex parenchyma ofTentacularia coryphaenae Bosc 1802. Their structure, position, mode of secretion and possible functions have been elucidated through standard histochemical techniques. An overview of the structure and function of similar glands in other cestodes is also presented.
TL;DR: In this article, a detailed study of the libratory modes of H2O molecules in the i.r. spectra of SrX2 · 6H2O (X = Cl, Br) is reported.
TL;DR: Variational Monte Carlo calculations have been made for the s-shell hypernuclei and also of Λ 9 Be with a 2α + Λ model as mentioned in this paper, where the well depth is calculated variationally with the Fermi hypernetted chain method.
TL;DR: In this article, 2H-Azirine derivatives (IV, V and VI) of acetylenic fatty acid esters, methyl 10-undecynoate (I), methyl 9-decyclic acid (II), and methyl 9 octadecynoate (III), respectively, have been obtained with the help of spectral and micro analyses.
Abstract: Lead tetraacetate (LTA) oxidations of N-aminophthalimide in the presence of acetylenic fatty acid esters have resulted in the formation of corresponding 1H-azirines that spontaneously rearranged to give 2H-azirines in moderate yields. 2H-Azirine derivatives (IV, V and VI) of acetylenic fatty acid esters, methyl 10-undecynoate (I), methyl 9-undecynoate (II) and methyl 9-octadecynoate (III), respectively, have been prepared and characterized with the help of spectral and micro analyses.
TL;DR: In this article, the dimensionless time parameter (τ) was evaluated as a function of fractional exchange of H(I) for some bivalent ions and of the bivalent ion for H (I) using the explicit approximation given by Helfferich et al., applicable to a particle diffusion-controlled ion exchange process.
TL;DR: Experiments indicate that in the presence of nicotinamide, streptozotocin causes the formation of a greater proportion of alkylated bases in relation to alkyl phosphotriesters.
Abstract: S1 nuclease hydrolysis and hydroxyapatite chromatography were used to study the effect of the alkylating antibiotic, streptozotocin, on the secondary structure of DNA. Native calf thymus DNA was alkylatedin vitro with increasing concentrations of streptozotocin and subjected to S 1 nuclease hydrolysis. An increasing degree of DNA degradation was seen, suggesting a destabilization of the secondary structure. Indirect evidence, deduced from alkaline hydrolysis, effect of NaCl on S1 nuclease hydrolysis, and hydroxyapatite chromatographic analysis of alkylated DNA, suggested a significant alkylation of DNA phosphates in addition to DNA bases. Nictotinamide has been reported to alter the cytotoxic and carcinogenic effects of streptozotocin. Our experiments indicate that in the presence of nicotinamide, streptozotocin causes the formation of a greater proportion of alkylated bases in relation to alkyl phosphotriesters. This may have significance in relation to the differential cytotoxicity of streptozotocin in the absence and presence of nicotinamide.
TL;DR: Seed oil ofCupania anacardioides (Sapindaceae) was found to contain cyanolipid I and cyanolIPid III at 41.3% and 11.7%, respectively.
Abstract: Seed oil ofCupania anacardioides (Sapindaceae) was found to contain cyanolipid I and cyanolipid III at 41.3% and 11.7%, respectively. Structures of these cyanolipid fractions were confirmed by spectroscopic methods.
TL;DR: Results from a study of interactions of a 340-GeV/c beam with emulsion nuclei at the CERN SPS are presented and limits are placed on the heavy-particle annihilation cross sections in the formation process.
Abstract: Results from a study of interactions of a 340-GeV/c beam with emulsion nuclei at the CERN SPS are presented. Some characteristics of heavy- and shower-particle multiplicity distributions are reported. The Koba-Nielsen-Olesen scaling hypothesis has been tested. Single-particle pseudorapid- ity distributions and rapidity-gap distributions have been studied in detail. The pseudorapidity distributions show a bimodal structure in all A interactions and the rapidity-gap distributions indicate the production of clusters during the multiparticle production process. The production of heavy clusters has also been studied using the rapidity-interval method proposed by Adamovich et al. The result shows that 340 GeV is belgical-model predictions for this ratio in nuclear matter are approx. =10 . Any comparison of these two values assumes no mass fractionation has occurred in the geophysical disposition and subsequent extraction of the sodium forming the atomic beam and also no differences in the distribution of heavy isotopes among the elements, compared to normal isotopes, during their astrophysical formation. Making these assumptions enables limits to be placed on the heavy-particle annihilation cross sections in the formation process.
TL;DR: The chromatographic behavior of metal ions on silica gel thin layers has been studied in aqueous formic acid and mixed annealing systems containing formic acids as mentioned in this paper.
Abstract: The chromatographic behaviour of some metal ions on silica gel thin layers has been studied in aqueous formic acid and mixed aqueous-organic solvent systems containing formic acid. Many analytically important separations of cations have been achieved in varying concentrations of formic acid solution in DMSO, acetone, and methyl ethyl ketone. Semiquantitative determination of nine cations has also been attempted.
TL;DR: In this paper, a chemical analysis of seven seeds of six species of plants belonging to six different botanical families have been carried out with the help of UV, IR, TLC-GLC techniques.
Abstract: Physico-chemical analysis of seven seeds of indigenous species of plants belonging to six different botanical families have been carried out with the help of UV, IR, TLC-GLC techniques. All the seed oils were found in agreement with the simple fatty acid composition i.e. linoleic-oleic-palmitic type. The chief components among unsaturated acids in the six seed oils are oleic and linoleic acids together forming 40.0-86.0 %. Polygonum sp. surprisingly is found to have combined content of oleic and linoleic acid 13.3 % only but having unexpected high amount of linolenic acid (37.8 %). Among saturated acids, palmitic acid was predominant acid found in the range of 10.0-483 %. This chemical screening of seed oils reveals that the species producing highly unsaturated oils merit attention for utilization as minor seed oils.
Untersuchungen an weniger bedeutenden Saatolen XII
Es wurden mittels UV,IR und DC-GC-Techniken physikalisch-chemische Analysen von sieben Saaten einheimischer Pflanzenarten, die zu sechs unterschiedlichen Pflanzenfamilien gehoren, durchgefuhrt. Man fand heraus, das alle Saatole mit der einfachen Fettsaurezusammensetzung des Typs Linol-, Ol-, Palmitinsaure ubereinstimmen. Die Hauptbestandteile unter den ungesattigten Sauren der 6 Saatole sind Ol- und Linolsaure, die zusammen 40.0-86.0% ausmachen. Uberraschenderweise zeigte sich, das Polygonum sp. einen Gesamtgehalt an Ol- und Linolsaure von nur 13.3 % hatte, wahrend es einen unerwartet hohen Gehalt an Linolensaure besas (37.8%). Unter den gesattigten Sauren dominierte Palmitinsaure mit 10.0-48.3%. Diese chemische Untersuchung zeigt, das Arten, die hochungesattigte Ole liefen, Beachtung zur Nutzung als weniger bedeutende Saatole verdienen.