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A field experiment was conducted with 8 genotypes of vegetable pea and 3 levels of rhizobial inoculation for two consecutive years. Inoculation with Rhizobium leguminosarum @ 20 g kg −1 seed made the plants taller and enhanced biomass production through branching, but delayed maturity. It resulted in more pods, enlarging them to contain more seeds, leading to higher test weight and enhanced harvest index. It increased nodulation, the benefit of which was reflected in most of the yield traits. It also enriched the seeds with nitrogen and protein, as well as activating nitrogenase enzyme in the root nodules to fix more atmospheric nitrogen.

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Abstract  

The present work deals with study of uptake behavior of zinc and mercury ions by hydrous ceric oxide applying a radiotracer technique. The influence of various parameters such as concentration, temperature and pH have been examined. It was observed that the amount of zinc and mercury ions adsorbed at equilibrium increases with increase of adsorptive concentration (1.0·10−7 to 1.0·10−2M), temperature (303–333K) and pH (ca. 3–10). Concentration dependence data agree well with the classical Freundlich isotherm. The radiation stability of hydrous ceric oxide was also investigated by exposing it to a 11.1 GBq (Ra−Be) source associated with γ-dose of 1.72 Gy·h−1 and also using a60Co source (4.66 kGy·h−1). Adsorption of these metal ions in the presence of some monovalent and divalent cations and complexing agents has also been included in the study.

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This paper reports findings from a study on the perceptions of work climate and the patters of relationships between work climate dimensions and performance of research and development units in six countries. The study is based on the analysis of the subset of date collected in Argentina, Egypt, India, Republic of Korea, Poland and UkSSR for the second round of International Comparative Study on the Organization and Performance of Research Units. The following dimensions of work climate have been usec: morale, openness, job satisfaction, work contacts, career opportunities, satisfaction with supervisor, information on research plans, research autonomy. Stepwise regression analyses were carrier out separately for each country and also on global sample to find out the important dimensions of work climate in explaining the variations in the performance of R&D units. The set of work climate dimensions are related separately for two different measures of performance of research units, viz. (1) scientific effectiveness; and (2) user-oriented effectiveness. The implications of this study for management of research and development groups are discussed.

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Inorganic particulates in removal of toxic heavy metal ions

VIII. Removal of zinc, cadmium and mercury ions from aqueous solution by hydrous titanium oxide

Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Mishra and V. Singh

Abstract  

Adsorption behavior of zinc, cadmium and mercury ions on hydrous titanium oxide in aqueous solution has been studied as a function of concentration of the metal ion (10−2−10−7M), temperature (303–333 K) and pH 3–10 by applying radiotracer technique. The kinetics of adsorption follows the first order rate law and agrees well with the classical Freundlich isotherm. The removal was found to increase with increasing pH but was suppressed in the presence of EDTA. The overall process is endothermic and irreversible in nature.

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The present report is in continuation to our earlier reports on the identification and fine mapping of three aroma QTLs in basmati rice using a bi-parental mapping population derived from a cross between Pusa 1121, a basmati rice variety, and Pusa 1342, a non-aromatic rice variety. We used a combination of genetic mapping and transcriptome profiling to narrow down the number of differentially expressed genes in rice to identify potential candidate genes for rice grain aroma. Highly aromatic and non-aromatic recombinant inbred lines (RILs) were identified through sensory analysis of mature milled grains. RILs with similar phenotypes were bulked together using bulk segregant analysis approach which drastically reduced the number of differentially expressed genes from 4016 to 1344. The transcriptome profiles generated were analyzed through Affymetrix rice genome array containing probe sets designed from all the predicted rice gene sequences. Microarray-based transcriptome profiling revealed one down-regulated gene co-located in QTL region aro3.1 on chromosome 3, eight genes co-located in the aro4.1 region on chromosome 4 and the badh2 gene on chromosome 8 to be differentially expressed in the aromatic parent and aromatic bulk. These genes are the most suitable candidates for future validation and development of new molecular functional markers to facilitate marker assisted breeding.

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Movement and abstraction of groundwater in the geological formations are dependent on the hydro-geological parameters of the aquifers. The purpose of any aquifer test is to determine the hydro-geological parameters. Among the basic parameters are the specific storage, permeability and leakage coefficients. The hydro-geological parameters are hidden in the field test data and their identification is possible using the available physically plausible models suitable for the prevailing field circumstances. In this context, a generalized theoretical solution for the effect of partial penetration superimposed over the full penetration on draw-down in a large-diameter well in artesian aquifer discharging at a constant rate has been presented for non-dimensional quantities describing the variable geometries of wells. The well-function curves are developed by varying the percentage amount of drilling and the percentage amount of casing lowered which then control to vary the percentage amount of open-hole or screened interval for the three categories: when the diameter of the cased interval in which the water level changes is greater than, equal to, and less than the diameter of the open interval. The skin effect and the effect of leakage are neglected. A comparison of results with the published works has also been presented. The present study is useful in such areas where wells are located either in harder or in collapsible loose formations; and a decision is required that, at the planning, construction, or development stage, as to what extent the amount of drilling be reduced, and/or an additional amount of casing be lowered within the aquifer. Also this reduces the cost of well construction and development in a specific situation.

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Aphids have acquired the status of major pest in North-western plains of India. A complex of five species infests the wheat in this part of the country. The diatomaceous earth (DE) has the potential to substitute the most widely used method of chemical control. Laboratory and field investigations were conducted to evaluate the effectiveness of DE either as soil or foliar application for suppression of wheat aphids during 2013–2014 and 2014–2015. The fecundity, adult longevity and total developmental duration of Rhopalosiphum padi decreased with the increasing dosage of soil application of DE in laboratory evaluation. However in field studies, no significant difference in aphid population was observed among different levels of DE application in soil. Foliar application of DE 150 kg/ha and higher dosages significantly reduced aphid population for initial two days but thereafter it had no effect on aphid prevalence. Wheat plant dusted with different dosages of DE did not show any visible injury but the reduction in chlorophyll content was observed in them. Overall, poor field efficacy coupled with loss of chlorophyll and safety issues relating to foliar application of DE proved against its use for control of sucking insect pests.

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Time dependent seismicity investigation in six seismogenic sources of Nepal and its adjoining areas in the Central Himalaya reveal that there is intermediate time clustering of the moderate size shallow earthquake in each seismogenic source. The inter-event times, between the successive shallow mainshocks, of the magnitude equal to or larger than certain cut-off magnitudes for each of these sources are used for long-term earthquake hazard prediction corresponding to individual sources of the region. For the hazard estimation, the following relations have been established here as: log T t = 0.46 M min +0.07 M p +0.02 log m 0 −2.38, and M f = 0.78 M min −0.25 M p −0.04 log m 0 + 4.32, where T t is the inter-event time measured in years; M min is the moment magnitude of the smallest mainshock considered; M p is the magnitude of preceding main shock, M f is the magnitude of the following mainshock and m 0 is the moment rate in each source per year. The value of σ = 0.22 and multi-correlation coefficient, R = 0.62 for the first equation and σ = 0.30 and R = 0.59 for the second equation are estimated.Based on these relations and using the magnitude and time of occurrence of the last main shocks in each seismogenic source, time dependent conditional probabilities of the next shallow main shocks during the next 10, 20 and 30 years as well as the magnitude of the expected main shocks are forecast.

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Seismically Kutch peninsula is very active. The distribution of seismicity in Peninsular Shield region from 1902 to 2001 show 12 earthquakes of M ≥ 6. The energy ratio from Kutch basin to Deccan trap is 20:1 and from trap to rest of the shield is 5:1. The last one hundred years seismicity data show Kutch basin is seismically more active than Deccan trap and the rest of the Peninsular Shield. The maximum magnitude of earthquake in the Kutch region is 7.7. The generations of large earthquakes in the region are difficult to explain, as plate boundary does not exist. In order to understand the physical processes that are taking place in the region to generate such large events the detailed analyses of geophysical and geological data have been examined in the light of development of rift, subsidence of basin, vertical tectonics and recent geophysical findings. In such regions, petrologic model can provide better explanation for release of fluid that generates large earthquakes, sprouting of sands, liquefaction, and large number of aftershocks activities and direction of stresses for aftershock sequences. The presence of magma in the Kutch upper mantle could be derived from various geological (subsidence of basin, development of rift faults) and geophysical observations (high heat flow over Cambay region, prominent positive Bouguer gravity anomalies and low shear velocity in the upper mantle). The inspection of seismological data shows all the medium size to large earthquake have occurred in shear zone of large gravity gradients or along the four major faults of the region. In view of geological and geophysical observations, petrologic model is proposed for generation of earthquakes in the region. The number of aftershocks and direction of stresses in the focal region of aftershocks would depend on the direction of movement of fluid incursion in the focal region after the occurrence of the main events. The recent Bhuj earthquake also shows more than 3000 aftershocks from Jan 29 to April 15, 2001. The expanding swarm activity in the focal region and the direction of stresses derived from first motion data of aftershocks for focal depths 2 to 8 km, 8 to 25 km, and 25 to 38 km supports the proposed model. Also, shear wave tomography studies in this region have revealed low shear wave velocity in the upper mantle of Cambay from shallow depth to 200 km depth showing high temperature zone. The analyses reveal the presence of conducting fluid in the focal zone, which is the main cause for generation of medium size to large earthquake in the region.

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