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Recent results of the WA98 experiment with Pb induced reactions at 158. A GeV are presented. The scaling properties of the transverse energy and the charged particle multiplicity at midrapidity with the number of participants is studied. Neutral pion spectra are compared to hydrodynamical parameterizations. The analysis of collective flow at target rapidity and at midrapidity is presented. The status of the study of direct photons and the search for isospin fluctuations is discussed.

Neutral pion production in central 158A GeV [sup 208]Pb+ [sup 208] Pb collisions has been studied in the WA98 experiment at the CERN Super Proton Synchrotron. The [pi][sup 0] transverse mass spectrum has been analyzed in terms of a thermal model with hydrodynamic expansion. The high accuracy and large kinematic coverage of the measurement allow one to limit previously noted ambiguities in the extracted freeze-out parameters. The results are shown to be sensitive to the shape of the velocity distribution at freeze-out. [copyright] [ital 1999] [ital The American Physical Society ]

Thermal creep occurs in all nonisothermal gas–mixture systems. The effect is more pronounced in rarefied gases and can play a significant role in, for example, microgravity crystal growth experiments, where natural convection is suppressed. Experimental measurements of the thermal creep in gas mixtures are, however, simply not available. We report experimental measurements of thermal creep in three binary gas mixtures: He:Ar, He:CO2, and Ar:CO2 at different mole ratios (mixture fractions). A stainless steel two-bulb measurement system employing seven capillaries to connect the bulbs is used to measure the steady-state pressure differences that develop between the bulbs for each mixture at a selection of total system pressures. Values of the total system pressure that were used range from 0.12 to 10.00 Torr. For all of the data reported, the two bulbs were held at temperatures of 397 and 297 K for the hot and cold sides, respectively. From the measured pressure differences, experimental values are obtained...

Different criteria of designing electron gun, slow-wave structure, magnetic focusing system and multi-stage depressed collector for a highly efficient space TWT are presented in this paper.

Solid-desiccant dehumidifiers are increasingly becoming an integral part of desiccant based air-conditioning systems because of their effective handling of latent heat loads compared to conventional vapor compression units. In these units, either a silica gel or a molecular sieve is used for dehumidification of air. Both of them have the capability to co-adsorb various chemical pollutants during dehumidification of air. However, the shape of the isotherm for water vapor on these materials is not favorable for desiccant cooling applications. A mixture (IM desiccant) containing a silica gel, a molecular sieve, and a hydrophobic molecular sieve that was coated on an aluminum foil was studied for its capability for simultaneous removal of moisture and some selected pollutants from air. Experimental data were obtained in a fixed bed adsorber that simulated the operation of a rotary desiccant wheel. Air to be dehumidified and cleaned and the hot regeneration air were cycled in a specific time interval through this bed. The shape of the water isotherm on IM desiccant was found to be in between that of silica gel and molecular sieve 13×, but its uptake capacity was significantly lower than that of either silica gel or molecular sieve. A flow rate of about 100 L/min that provided a face velocity of about 132 cm/s was used in the adsorption step. The flow rate during regeneration was about 50 L/min. The temperature of the inlet air was about 23°C and its relative humidity was varied between 20 percent and 80 percent. The concentrations of pollutants were as follows; carbon dioxide: 1050 and 2300 ppm; toluene: 32 ppm; 1,1,1-trichloroethane: 172 ppm, and formaldehyde: 0.35 ppm. A complete breakthrough of all the pollutants was observed during an adsorption cycle. However, a removal efficiency greater than 50 percent for these pollutants was observed if the adsorption cycle time was about 1 minute.

The production of neutral pions in 158A GeV {sup 208}Pb+ {sup 208}Pb collisions has been studied in the WA98 experiment at the CERN Super Proton Synchrotron (SPS). Transverse momentum spectra are studied for the range 0.3{le}m{sub T}{minus}m{sub 0}{le}4.0 GeV /c . The results for central collisions are compared to various models. The centrality dependence of the neutral pion spectral shape and yield is investigated. An invariance of the spectral shape and a simple scaling of the yield with the number of participating nucleons is observed for centralities with greater than about 30thinspthinspparticipating nucleons. This is most naturally explained by assuming an equilibrated system. {copyright} {ital 1998} {ital The American Physical Society }

Transition energies, oscillator strengths and transition probabilities have been reported for the high lying quadrupolar excited states up to principal quantum number n = 7 for the first few members of the Cl isoelectronic sequence from Cl to Cr7+. A linearised version of the time-dependent coupled Hartree–Fock (TDCHF) theory has been adopted to calculate such transition properties. The data are very useful to explain the unidentified lines in the spectrum of the solar corona and flares. Most of the data for oscillator strengths and transition probabilities are new. Transition energies agree well with the existing experimental results wherever available.

Anisotropic transverse flow has been studied with a magnetic spectrometer at midrapidity and the Plastic Ball detector at target rapidity in the WA98 experiment. Our preliminary results show the existence of directed and elliptic flow in semi-central Pb+Pb collisions. The magnitude of the directed flow is found to be significantly smaller than those observed at the AGS energies.

Most of the emissions (about 60 per cent) from automobiles occur during a cold start before the catalytic converter becomes active. The use of an adsorbent trap for temporary storage of emitted hydrocarbons before catalysts attain the light-off temperature in the converter has been investigated as a means for reduction of cold-start emissions. The hydrocarbon emissions can be reduced significantly if the hydrocarbons are retained by the trap until catalysts reach the light-off temperature. The effect of engine speed on the emission of NO x, CO and hydrocarbons and their subsequent retention in the adsorption trap was studied. A hydrophobic adsorbent, Hisiv-1000, and molecular sieve 13X were used individually and in conjunction in the trap to adsorb hydrocarbons. Although significant amounts of hydrocarbons were adsorbed in the trap initially, they were released from the trap rather quickly even before catalysts reached the light-off temperature.

Neutron evaporation spectra alongwith γ -multiplicity has been measured from the 185 Re * compound nucleus at the excitation energies ~27 and 37 MeV. Statistical model analysis of the experimental data has been carried out to extract the value of the inverse level density parameter k at different angular momentum regions ( J ) corresponding to different γ -multiplicity. It is observed that, for the present system the value of k remains almost constant for different J . The present results on the angular momentum dependence of the nuclear level density (NLD) parameter a (=A/k) , for nuclei with A ~180 is quite different from our earlier measurements in case of light and medium mass systems. The present analysis provides useful information to understand the angular momentum dependence of NLD at different nuclear mass regions.

An excited state of 12 C having excitation energy (E x ) 9.65 ± 0.02 MeV and width (FWHM) 607 ± 55 keV, which decays to three α particles via Hoyle state (E x = 7.65 MeV), has been directly identified in the exclusive inelastic scattering of 60 MeV 4 He on 12 C, measured in coincidence with the recoiling 12 C Hoyle state (decaying mostly as 12 C* → 8 Be gs → α → α + α + α) by event-by-event kinematic reconstruction of the completely detected (4α) events. This state is likely to be a candidate for 2 2 + first excited of Hoyle state.

The 9Be(28Mg,27Na) one-proton removal reaction with a large proton separation energy of Sp(28Mg)=16.79 MeV is studied at intermediate beam energy. Coincidences of the bound 27Na residues with protons and other light charged particles are measured. These data are analyzed to determine the percentage contributions to the proton removal cross section from the elastic and inelastic nucleon removal mechanisms. These deduced contributions are compared with the eikonal reaction model predictions and with the previously measured data for reactions involving the re- moval of more weakly-bound protons from lighter nuclei. The role of transitions of the proton between different bound single-particle configurations upon the elastic breakup cross section is also quantified in this well-bound case. The measured and calculated elastic breakup fractions are found to be in good agreement., Comment: Phys. Rev. C 2014 (accepted)

A field experiment was conducted with wetland rice (Oryza sativa cv. IR-36) in a sandy clay loam soil (Entisol) to study the effect of inoculation with a soil-based mixed culture of four diazotrophic cyanobacteria,Aulosira fertilissima, Nostoc muscorum, N. commune andAnabaena spp., on the N-flux in inorganic NH4++NO3−+ NO2−), easily oxidizable, hydrolysable and non-hydrolysable forms of N in soil during vegetative growth periods of the crop. Effects on grain and straw yield and N uptake by the crop were estimated. The effects of applying urea N and N as organic sources, viz.Sesbania aculeata, Neem (Azardirachta indica) cake and FYM, each at the rate of 40 kg N ha−1, to the soil were also evaluated. Inoculation significantly increased the release of inorganic N, evidenced by its increased concentrations either in soil or in soil solution. However, such increases rarely exceeded even 4% of total N gained in different froms in the soil system by inoculation during the vegetative growth stages of the rice plant, when the nutritional requirement of the plants is at a maximum. Most of the N2 fixed by cyanobacteria remained in the soil as the hydrolysable form (about 85%) during this period. Inoculation caused an insignificant increase in grain (8%) and straw (11%) yield, which was, however, accompanied by a significant increase in N uptake by the grain (30%) and an increase in total uptake of 15.3 kg N ha 1. Such beneficial effects of inoculation varied in magnitude with the application of organic sources, with farmyard manure (FYM) being the most effective. Application of urea N, on the other hand, markedly reduced such an effect.

Energy levels, dipole oscillator strengths and transition probabilities for some highly stripped ions of Fe-group elements Fe8+, Co9+, Ni10+, Cu11+ and Zn12+ belonging to the astrophysically important Ar-isoelectronic series have been evaluated using the time-dependent coupled Hartree-Fock theory. The data can be employed to the analysis of spectral lines in the solar spectrum, high temperature astrophysical and laboratory plasma diagnostics. Estimated values compare favourably with existing experimental and theoretical data wherever available and many new ones reported here may constitute a useful set for future reference.

The first evidence of directed flow at 158 A GeV Pb + Pb collisions is observed using the Plastic Ball detector in WA98 experiment. The azimuthal angle of the total transverse energy, Phi(o), is determined for each event using the observed protons in the Plastic Ball. A clear azimuthal asymmetry of fragments is observed with respect to Phi(o). The degree of azimuthal asymmetry is found to be largest in mid-central collisions, which is consistent with the picture of the collective flow.The p(t) spectra of particles measured in the mid-rapidity spectrometer has been studied in conjunction with the Plastic Ball, and different p(t) slopes with respect to Phi(o) for proton and pi(+) are observed.

The excited states in the odd-$A$ $^{197}$Tl nucleus have been studied by populating them using the $^{197}$Au($\alpha$, 4$n$)$^{197}$Tl reaction at the beam energy of 48 MeV. The $\gamma-\gamma$ coincidence data were taken using a combination of clover, LEPS and single crystal HPGe detectors. Precise spin and parity assignments of the excited states have been done through the polarization and the DCO measurements. A new band structure has been identified and the evidence for a possible intruder $\pi i_{13/2}$ state has been found for the first time. Possible configurations of the observed bands have been discussed. The total Routhian surface calculations have been performed to study the shape of $^{197}$Tl for different configurations.

Neutron evaporation spectra at backward angles from ${}^{201}$Tl${}^{*}$, ${}^{185}$Re${}^{*}$, and ${}^{169}$Tm${}^{*}$ compound nuclei, having different ground-state deformations, have been measured at two excitation energies (${E}^{*}$ $\ensuremath{\sim}$ 37 and 26 MeV). The values of the inverse level density parameter ($k$), extracted at these excitations using statistical model calculations, are observed to decrease substantially at the lower excitation energy ($\ensuremath{\sim}$26 MeV) for nuclei having large ground-state deformation (residues of ${}^{185}$Re${}^{*}$ and ${}^{169}$Tm${}^{*}$), whereas for near-spherical nuclei (residues of ${}^{201}$Tl${}^{*}$), the $k$ value remains unchanged at the two energies. The decrease in $k$ at the lower excitation energy for the deformed systems amounts to a relative increase in nuclear level density, indicating a collective enhancement. The present observation clearly establishes the existence of a strong correlation between collectivity and ground-state deformation.

A high-statistics, high-resolution, complete kinematical measurement has been performed to estimate the quantitative contributions of various direct 3$\ensuremath{\alpha}$ decay mechanisms in the decay of the famous Hoyle state, the ${0}_{2}^{+}$ resonant excited state of ${}^{12}$C at an excitation energy of 7.654 MeV, using inelastic scattering of 60-MeV $\ensuremath{\alpha}$ particles on ${}^{12}$C. The present observation of nonzero branching ratios of various direct 3$\ensuremath{\alpha}$ decay modes, which have been extracted using $\ensuremath{\sim}$20$\phantom{\rule{0.16em}{0ex}}$000 fully detected (4$\ensuremath{\alpha}$) Hoyle events, is expected to remove the ambiguities among various previous estimates, extracted from fewer ($\ensuremath{\lesssim}$5000) events.

Inclusive energy spectra of the complex fragments (3 $\leq$ Z $\leq$ 5) emitted in the reactions $^{12}$C (77 MeV)+ $^{28}$Si, $^{11}$B (64 MeV)+ $^{28}$Si and $^{12}$C (73 MeV)+ $^{27}$Al (all having the same excitation energy of $ \sim$ 67 MeV), have been measured in the angular range of 10$^\circ$ $\lesssim \theta_{lab} \lesssim$ 60$^\circ$. The fully energy damped (fusion-fission) and the partially energy damped (deep inelastic) components of the fragment energy spectra have been extracted. It has been found that the yields of the fully energy damped fragments for all the above reactions are in conformity with the respective statistical model predictions. The time scales of various deep inelastic fragment emissions have been extracted from the angular distribution data. The angular momentum dissipation in deep inelastic collisions has been estimated from the data and it has been found to be close to the corresponding sticking limit value., Comment: 8 pages, 8 figures

Measurements of direct photon production in p + Pb and p + C collisions at root(NN)-N-s = 17.4 GeV are presented. Upper limits on the direct photon yield as a function of p(T) are derived and compared to the results for Pb + Pb collisions at root(NN)-N-s = 17.3 GeV. The production of the eta meson, which is an important input to the direct photon signal extraction, has been determined in the eta -> 2 gamma channel for p + C collisions at root(NN)-N-s = 17.4 GeV. (c) 2012 Elsevier B.V. All rights reserved.

We present theoretical results for electron emission in collisions between helium atoms and dressed projectiles at high energies. Double-differential cross sections (DDCSs) as a function of the emitted electron energies and angles are calculated. In our study we have applied the three-body formalism using the three-Coulomb wave (3CW–3B) model. The interaction between the dressed projectile and the active electron in the target has been approximated by a model potential having both a long-range Coulomb potential part and a short-range part. However, the active electron in the target has been treated as hydrogenic. We have also studied the projectile charge state dependence of the DDCS. Our theoretical results are compared with available experimental data as well as other theoretical calculations. The comparison shows a good agreement between the present calculations and the measurements. The obtained results are also compatible with other theoretical findings.

Time-dependent coupled Hartree–Fock theory was applied to estimate the allowed oscillator strengths of the astrophysically important highly stripped ions of the carbon isoelectronic sequence Ne4+, Mg6+, Si8+, S10+, Ar12+, Ca14+, and Ti16+ from their ground and valence-excited states up to principal quantum number n = 6. Oscillator-strength values compare favourably with the existing available data and many of the results are reported for the first time.

Ghosh, Tapan K., Michael R. Van Scott, and Oommen P. Mathew. Epithelial modulation of afferent nerve endings : differential effects of amiloride on afferent subtypes. J. Appl. Physiol. 78(6) : 2235-2240, 1995.-Mechanisms underlying the differing chemosensitivity of laryngeal afferents have not been defined. The role of airway epithelium in transducing the chemical stimuli to neural signals was investigated by using Na + - and Cl - -channel inhibitors in anesthetized spontaneously breathing cats. Single-fiber action potentials were recorded from the peripheral cut end of the superior laryngeal nerve. Luminal application of amiloride (10 -4 M), an inhibitor of epithelial Na + channels, reduced the responsiveness of non-respiratory-modulated endings (n = 25) to distilled water (65.76 ± 5.77 vs. 50.67 ± 5.13 Hz ; P < 0.01). Water responsiveness of these endings was unaffected by 4,4'-diisothiocyanostilbene-2,2 '-disulfonic acid and diphenylamine-2-carboxylate, two Cl - -channel blockers. Respiratory-modulated endings (water responsive, n = 8 ; water nonresponsive, n = 9) were unaffected by Na + - and Cl - -channel blockers. These results suggest that epithelial Na + channels play a role in the modulation of non-respiratory-modulated laryngeal endings. The lack of an effect by amiloride on other subtypes may be due to differences in location or intrinsic properties of nerve endings. Cl - channels do not appear to play an important role in the modulation of laryngeal afferents targeted in this study.

As a part of our detailed comparative studies of groups of Liquid Crystalline compounds belonging to N(p-n-Alkyloxy Benzylidene) P′-Alkylanilines, (nO.m′s), we present here the phase transition studies of the compounds 90.8 and 100.6 using X-Ray diffraction study. The compounds 100.6 and 90.8 exhibit ACFG phase variant. The temperature dependence of tilt angle in Sm C and Sm F phases in both of the compounds is presented. A comparative study of tilt angle measured by different experimental techniques is also presented.

The interaction of an E/A=70 - MeV 7Be beam with a Be target was used to populate levels in 6Be following neutron knockout reactions. The three-body decay of the ground and first excited states into the alpha+p+p exit channel were detected in the High Resolution Array. Precise three-body correlations extracted from the experimental data allowed us to obtain insight into the mechanism of the three-body democratic decay. The correlation data are in a good agreement with a three-cluster-model calculation and thus validate this theoretical approach over a broad energy range., 5 pages, 7 figures; Corrected typos

Neutron evaporation energy spectra have been measured in coincidence with $\ensuremath{\gamma}$ rays of different multiplicities for ${}^{119}$Sb${}^{*}$ in the excitation energy range of $\ensuremath{\sim}31$--43 MeV. The inverse level density parameter ($k$) have been extracted for different angular momentum regions corresponding to different $\ensuremath{\gamma}$-ray multiplicities by comparing the experimental neutron energy spectra with statistical model prediction. It has been observed that the level density increases with the increase in angular momentum. Possible reasons for this variation have been discussed.

Hb Acharnes or [β53(D4) Ala - Thr] is a newly discovered unstable hemoglobin variant. It has been reported in very few literatures across the world and no cases have been reported from India till date. Hb Acharnes is known to interact with β°-thalassemia to produce thalassemia intermedia and heterozygotes may present with borderline HbA2 levels. Here we report a rare case discovered during routine screening of thalassemia and hemoglobinopathies in a 19 year old pregnant lady. To emphasize the diagnostic difficulties and importance of detection of a rare hemoglobin variant Hb Acharnes [β53(D4) Ala - Thr] in an asymptomatic patient in West Bengal, India. The 19 year old asymptomatic pregnant lady P1+0, LMP - 21.01.2011 reported in antenatal OPD of Burdwan Medical CollegeHospital, Burdwan, West Bengal, India for routine follow up. After proper antenatal check up her blood was collected as a routine screening for Thalassemia, EDTA blood was taken on 5th April 2011 and was subjected to Hemoglobin estimation by Cyanmethemoglobin method, Cell parameters in automated cell counter (SYSMEX KX21) and Hemoglobin analysis by HPLC in BIORAD VARIANT system. The patient was normal with respect to clinical examination and urinalysis. Routine blood counts revealed mild microcytic hypochromic anemia and on HPLC an unknown band (retention time 2.2 minutes, 21.2%, appearing as a shoulder of HbA0 band) of hemoglobin variant was discovered with normal level of HbF and HbA2. Hemoglobin analysis of her mother showed similar pattern while her father and her husband had normal Hb-HPLC pattern. The unknown hemoglobin variant was identified as Hemoglobin Acharnes or [β53 (D4) Ala - Thr] by the Biorad laboratories upon consulting the standard chromatogram patterns for this particular hemoglobin variant. Only Haemoglobin Electrophoresis by conventional gel technique may miss the case and the HPLC pattern may be used as a standard control for identification.

An experiment was conducted to exploit the immune-modulation effect of trivalent chromium (Cr) for augmenting immunity against peste des petits ruminants (PPR) in dwarf black Bengal goats (Capra hircus). The goats (n = 6 per treatment group) either received a basal diet devoid of supplemental Cr (control) or were supplemented with 0.5 mg Cr as chromic chloride (+Cr) for 60 days. Live weight gain and feed conversion efficiency improved (P < 0.05) in the +Cr dietary group. Supplemental Cr did not affect the total number of monocytes, eosinophils and basophils (P > 0.1) although total leukocytes increased (P < 0.05) and the ratio of neutrophils to lymphocytes narrowed down (P < 0.05) in the +Cr dietary group. The effect of Cr supplementation on variables of the intravenous glucose tolerance test (IVGTT) was inconclusive. Compared to the control group, the basal concentration of glucose (P < 0.05) and insulin (P < 0.001) was higher, clearance rate was slower (P < 0.05) and serum half-life was greater (P < 0.05) in the +Cr dietary group during the IVGTT. Over the duration of the experiment, serum concentration of insulin increased (P < 0.001) and that of cortisol decreased (P < 0.01) in the +Cr group, which also showed a relatively higher primary antibody (Ab) response against PPR on days 10 (P < 0.01) and 20 (P < 0.05) post-vaccination. In conclusion, the experiment indicated that supplementation of Cr as CrCl3, in the diet of non-stressed goats, may improve primary Ab response against PPR and help confer an augmented immunity to the disease besides promoting growth and feed conversion.

Elastic scattering of alpha particles from 208Pb at higher energy is explained by a microscopic and phenomenological alpha potential. The same complex potential is used to calculate the alpha width of 212Po from the principle of detailed balance. The alpha width of the ground state can be reproduced to within a factor of 3 of the experimental value.

We report final-state-exclusive measurements of the light charged fragments in coincidence with 26Ne residual nuclei following the direct two-proton removal from a neutron-rich 28Mg secondary beam. A Dalitz-plot analysis and comparisons with simulations show that a majority of the triple- coincidence events with two protons display phase-space correlations consistent with the (two-body) kinematics of a spatially-correlated pair-removal mechanism. The fraction of such correlated events, 56(12) %, is consistent with the fraction of the calculated cross section, 64 %, arising from spin S = 0 two-proton configurations in the entrance-channel (shell-model) 28Mg ground state wave function. This result promises access to an additional and more specific probe of the spin and spatial correlations of valence nucleon pairs in exotic nuclei produced as fast secondary beams., Comment: accepted for publication in Physical Review Letters

Time-dependent perturbation theory has been applied to calculate the doubly excited triplet statesNsns:3Se,Npnp:3De andNdnd:3Ge (N=2, 3, 4,n=N+1, ... ,5) for He, Li+, Be2+ and B3+. A time-dependent harmonic perturbation causes simulataneous excitation of both the electrons with a change of spin state. The doubly excited energy levels have been identified as the poles of an appropriately constructed linearized variational functional with respect to the driving frequency. In addition to the transition energies, effective quantum numbers of these doubly excited states have been calculated and analytic representations of their wave functions are obtained. These are utilized to estimate the Coulomb repulsion term for these states which checks the consistency of the wave functions. These wave functions may also be used for calculating other physical properties of the systems.

Effects of intralaryngeal CO2 on the response of superior laryngeal afferents to negative pressure were investigated in 20 anesthetized spontaneously breathing adult cats. Single-fiber action potentials were recorded from the peripheral cut end of the superior laryngeal nerve. The larynx was exposed to negative pressure during inspiration when the animal breathed against an occluded upper airway. Among the 99 receptors evaluated, 54 were respiratory modulated and 45 were nonmodulated endings. The effect of intralaryngeal CO2 on the response of 39 receptors responding to negative pressure was determined by exposure of the larynx to CO2 or air for 1 min followed immediately by upper airway occlusion. The mean discharge frequency of 22 fibers inhibited by negative pressure was 32.4 +/- 2.6 Hz during air trials compared with 29.9 +/- 2.6 Hz during CO2 trials (P < 0.005). During occlusion of the upper airway after the warm humidified air trial, the discharge frequency of these endings decreased to 24.2 +/- 2.3 Hz compared with 17.5 +/- 2.2 Hz after CO2 trial (P < 0.001). The mean discharge frequencies of 17 fibers stimulated by negative pressure were 3.7 +/- 2.6 and 4.4 +/- 1.8 Hz, respectively, during air and CO2 trials. The mean frequencies increased to 14.7 +/- 3.5 Hz (air) and 18.6 +/- 4.0 Hz (CO2) during upper airway occlusions (P < 0.01). We conclude that intralaryngeal CO2 can alter the response of pressure-sensitive laryngeal afferents, thereby having a role in the maintenance of upper airway patency.(ABSTRACT TRUNCATED AT 250 WORDS)

Two types of airlift fermenters, conventional (UT-ALF) and modified (CDT-ALF) were investigated to evaluate their performance with respect to baker's yeast growth. The riser tube of conventional external loop airlift fermenter is replaced by a converging-diverging tube, which is named as modified airlift fermenter having downcomer to riser cross-sectional area ratio Ad/Ar=1.8.

Application of the time-dependent coupled Hartree—Fock theory of many-electron systems like the ions in the argon isoelectronic sequence reveals the occurrence of a new resonance, hitherto unreported in the literature. This resonance is observed from K + onwards and falls within the normal dispersion region for the isoelectronic ions having Z ⩾ 20 and is believed to be due to the dynamic correlations present in such systems. In the neighbourhood of this resonance dynamic polarizability values exhibit complex structure. The oscillator strength associated with the transition is found to be low.

Snakehead fish of the genus Channa have well-developed air-breathing organs (ABO) yet retain their gill arches for respiratory and non-respiratory functions. Alterations in the macrocirculation accompany inclusion of the ABO and appear to enhance gas exchange efficiency (Munshi et al., 1994. Anat. Rec. 238:77–91). In the present study, the microcirculatory anatomy of gill and ABO from two facultative air-breathing Channa, C. punctata and C. gachua, and one obligate air-breather, C. marulius, were examined in detail using scanning electron microscopy (SEM) of vascular corrosion replicas and fixed whole-sectioned tissue. The results show that the circulation in the filaments from the first, second, and third gill arches is similar to that found in water-breathing teleosts. Fourth gill arch microcirculation of C. punctata is not different from the other three, whereas in C. marulius, it has been greatly modified into a network of low-resistance vascular shunts, although remnants of an intralamellar filamental microcirculation remain. The vascular shunts are formed from extensions of afferent and efferent lamellar arterioles and the complete, or nearly complete, loss of a lamellar sinus. The vasculature of the ABO has been highly modified in all species into a coiled-spiral capillary network with a constricted aperture guarding a dilated capillary dome at the epithelial surface. Microvilli are found congregated on the aperture endothelium of C. punctata but they are virtually absent from C. marulius endothelium. Less than 15% of the ABO capillary surface appears to face the epithelium and thereby contributes directly to gas exchange. These findings suggest that the microvascular modifications observed in Channa entail more than a simple increase in the contact surface between ABO vessels and air and they may serve other unknown physiological functions. © 1994 Wiley-Liss, Inc.

This is the third of a three-part series describing an attempt to develop a comprehensive computational framework for aiding the engineering design of woven industrial fabrics. The main aim of this work is to develop a generalized knowledge-based CAD system for fabric design. The present status of this research has been described in [3]. Completing the CAD system entails detailed development of an analytic phase comprised of a set of computational models for simulation of fabric behaviour under external stimuli, and for the predictive estimation of some important properties. Toward that end, an analysis of uniaxial/biaxial load-deformation of a plain woven fabric has been developed under certain restrictive conditions. Part III describes, in detail, the theoretical and practical aspects of this analysis (model). A brief literature review of previous work on this subject is followed by a description of the mathematical model, its computational expression, and the experimental tests performed to validate th...

The macrocirculation in the head of three air-breathing species of Channa was examined with the aid of vascular corrosion replicas and a scanning electron microscopic study was conducted on the pseudobranch, choroid gland and lentiform body. Two facultative air-breathing murrles, C. punctata and C. gachua, and one obligate air-breather, C. marulius were examined. In all three, the air-breathing organs (ABO) and systemic circulations were in-parallel, and both were in-series with the branchial circulation. Efferent branchial arteries from the first and second gill arches formed the arterial supply to the ABO, whereas the third and fourth arch efferents perfused systemic tissues. Postbranchial blood from the second gill arch also entered the systemic circulation directly via a shunt from the efferent branchial artery to the lateral aorta and via hypobranchial arteries. Vascular specialization to prevent mixing of oxygenated ABO venous and deoxygenated systemic venous blood was evident in arterial, but not venous circuits. Pseudobranchs of C. gachua and C. punctata are tri-lobed, in C. marulius they have numerous lobules. Pseudobranch lamellae are wider and shorter along the axis of blood flow than gill lamellae and folded perpendicular to this axis. Pseudobranch lamellae appear to be modified to minimize their epithelial surface while retaining an extensive vascular endothelial-pillar cell surface area, counter-current amplification is also possible. The choroid gland is an extensive planar counter-current capillary rete. The lentiform body of the eye is a globular capillary rete but there is no evidence of a counter-current circulation. The choroid and lentiform rete may have distinct physiological functions. © 1994 Wiley-Liss, Inc.

Deviations from the isobaric multiplet mass equation are presented and discussed for the $A=7$, $T=3/2$ quartet and the $A=8$, $T=2$ quintet.

The interactions of an E/A=70-MeV {sup 9}C beam with a Be target was used to populate levels in Be, B, and C isotopes, which undergo decay into many-particle exit channels. The decay products were detected in the HiRA array and the level energies were identified from their invariant mass. Correlations between the decay products were examined to deduce the nature of the decays, specifically to what extent all the fragments were created in one prompt step or whether the disintegration proceeded in a sequential fashion through long-lived intermediate states. In the latter case, information on the spin of the level was also obtained. Of particular interest is the five-body decay of the {sup 8}C ground state, which was found to disintegrate in two steps of two-proton decay passing through the {sup 6}Be{sub g.s.} intermediate state. The isobaric analog of {sup 8}C{sub g.s.} in {sup 8}B was also found to undergo two-proton decay to the isobaric analog of {sup 6}Be{sub g.s.} in {sup 6}Li. A 9.69-MeV state in {sup 10}C was found to undergo prompt four-body decay to the 2p + 2{alpha} exit channel. The two protons were found to have a strong enhancement in the diproton region and the relativemore » energies of all four p-{alpha} pairs were consistent with the {sup 5}Li{sub g.s.} resonance.« less

Mass distribution of fission fragments and neutron multiplicity in the ${}^{16}\text{O}+{}^{238}$U reaction were measured at near- and below-barrier energies. A sudden change in the fragment mass width, observed in the present measurement, confirmed the transition to quasifission at below-barrier energies; the same was indicated earlier from the study of fission fragment angular anisotropy. However, the present measurement of prescission neutron multiplicity as well as the earlier measurement of evaporation residue yield did not indicate any significant departure from the respective statistical model predictions throughout the energy range. It is argued that the first two probes are more sensitive for highly asymmetric systems, whereas all probes would be useful and complimentary to each other for study of quasifission in more symmetric systems, where quasifission is more dominant.

A greenhouse experiment was conducted with wetland rice (Oryza sativa cv. IR-50) in a clay-loam soil (Fluventic Eutrochrept) to study the effect of cyanobacterial inoculation a mixed culture of Aulosira fertilissima, Nostoc muscorum, Nostoc spp., and Anabaena spp., applied at the rate of 0.15 g (dry weight pot-1 or 43 kg ha-1) on acetylene reduction activity in soil and the root system (excised root), and the grain and straw yield. The effects of applying P (40 kg ha-1), N (60 kg ha-1), and P+N to the soil were also evaluated. Cyanbacterial inoculation significantly increased (more than 200% on average) photo-dependent acetylene reduction activity in soils, particularly where the indigenous activity was considerably low, i.e. under unfertilized and N-fertilized conditions. The effect of inoculation was prominent at the maximum tillering and grain formation stages of the crop. This inoculation benefit was, however, marginal in P-applied soils (P and P+N), where the indigenous activity was stimulated more than threefold. The inoculation led to a remarkable increase in root-associative acetylene reduction activity after the maximum tillering stage of the crop, particularly with applied N but for other treatments this inoculation effect was not significant. Cyanobacterial inoculation also increased the grain and straw yield of the crop when N was not applied. The grain and straw yield was significantly correlated with the acetylene reduction activity in flooded soils and in the root system during the tillering and maximum tillering stages of rice growth, respectively.

Fractional gas holdup study was carried out in two airlift fermenters: one having of conventional design, the other having an asymetric riser arm. Air flow rate was varied from 1.5 to 9.0 cm/sec and gas hold-up values compared. Fractional gas holdup, ɛG, was strongly dependent on superficial gas velocity and initial liquid height. The modified fermenter always showed a higher gas holdup than the conventionally designed one.

An approach to modify external loop airlift bioreactor is presented that examines its performance with respect to mass transfer. There are various designs of airlift fermenter [1]. In the proposed system [2] the riser has been replaced by a tube of irregular geometry, in the form of converging-diverging sections (CDT-ALF), so that better mass transfer may be obtained due to better liquid mixing caused by the bubble flow, pulsation effect and early transition to turbulence. Mass transfer characteristics of the modified airlift fermenter CDT-ALF were studied and compared with those of a conventional one, UT-ALF. Overall volumetric mass transfer coefficient,KLa, was determined by sulfite oxidation method.KLa was determined with respect toUG for differenthi. HigherKLa was always observed in CDT-ALF compared to that in UT-ALF under any operating condition ofhi andUG. If theKLa values are compared in both the systems under their optimum conditions ofhi andUG, CDT-ALF showed 122.5% higher values ofKLa compared to UT-ALF. However, when both the systems were operated at the lowest experimental conditions ofUG, thekLa in CDT-ALF was found to be 170% higher. In UT-ALF while with the decrease ofUG,kLa decreased, in CDT-ALF the reverse was observed i.e. at lowUG,KLa was higher. However with the increase ofhi,KLa decreased in both the systems. To predict volumetric mass transfer coefficientKLa, empirical correlations were developed by dimensional analysis for both the reactors. The correlations were experimentally verified to determine their reliability to predict mass transfer coefficient and the deviation was found within reasonable limit.

$^{8}\mathrm{C}$ is found to decay to four protons and an $\ensuremath{\alpha}$ particle in two $2p$ emission steps. The correlations between the protons in the first step ($^{8}\mathrm{C}$ to $^{6}\mathrm{Be}$) exhibit a significant enhancement in the region of the decay phase space where the two protons have small relative energy, a region sometimes called the diproton region. The decay of the isobaric analog of $^{8}\mathrm{C}$ in $^{8}\mathrm{B}$ is also found to decay by $2p$ emission. This is the first case of isospin-allowed $2p$ decay between isobaric analog states.

The influence of alpha clustering on nuclear reaction dynamics is investigated using the giant dipole resonance (GDR) lineshape studies in the reactions 20Ne (Elab=145,160 MeV) + 12C and 20Ne (Elab=160 MeV) + 27Al, populating 32S and 47V, respectively. The GDR lineshapes from the two systems are remarkably different from each other. Whereas, the non alpha-like 47V undergoes Jacobi shape transition and matches exceptionally well with the theoretical GDR lineshape estimated under the framework rotating liquid drop model (RLDM) and thermal shape fluctuation model (TSFM) signifying shape equilibration, for alpha cluster 32S an extended prolate kind of shape is observed. This unusual deformation, seen directly via -decay for the first time, is predicted to be due to the formation of orbiting di-nuclear configuration or molecular structure of 16O+ 16O in 32S superdeformed band., 12 Pages, 5 Figures, Accepted for publication as Rapid Communication in Phys. Rev. C