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The alates of Sitobion avenae started settling on wheat during first week of January (standard week 1) simultaneously with the activity of its predator, Coccinella septempunctata . However, the population density of this predator at this stage was very less. From standard week 5, the aphid population started increasing steadily and colonies of alates and apterous aphids were seen on leaves and stem. Middle of February to the start of March was the most favourable period for multiplication of this pest. The maximum population of cereal aphid was observed during standard week 10 (second week of March), when wheat ( Triticum aestivum ) crop was in earing stage and the temperature was between 8.5 and 23.1° C along with a relative humidity of 45.7 to 88.3 per cent. The aphid started declining gradually during following weeks, finally disappearing by second week of April (standard week 15). Its predator, C. septempunctata was observed feeding on aphid colonies during standard week 4, which increased steadily till middle of April, when the aphid population started declining. This asynchrony in their population pattern in wheat crop is being contemplated to be the major cause of flare up of the population of this pest. The correlation drawn between different stages of predator and aphid population revealed that the collective contribution of these factors was 93.92 per cent. Abiotic (temperature and relative humidity) and biotic (predator) factors were observed to be significantly influencing the aphid population in this crop ecosystem.

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The use of gamma rays for the sterilization of pharmaceutical raw materials and dosage forms is an alternative method for sterilization. However, one of the major problems of the radiosterilization is the production of new radiolytic products during the irradiation process. Therefore, the principal problem in radiosterilization is to determine and to characterize these physical and chemical changes originating from high-energy radiation. Parenteral drug delivery systems were prepared and in vitro characterization, biodistribution and treatment studies were done in our previous studies. Drug delivery systems (liposomes, niosomes, lipogelosomes and niogelosomes) encapsulating diclofenac sodium (DFNa) were prepared for the treatment of rheumatoid arthritis (RA). This work complies information about the studies developed in order to find out if gamma radiation could be applied as a sterilization method to DFNa, and the raw materials as dimyristoyl phosphatidylcholine (DMPC), surfactant I [polyglyceryl-3-cethyl ether (SUR I)], dicethyl phosphate (DCP) and cholesterol (CHOL) that are used to prepare those systems. The raw materials were irradiated with different radiation doses (5, 10, 25 and 50 kGy) and physicochemical changes (organoleptic properties pH, UV and melting point), microbiological evaluation [sterility assurance level (SAL), sterility and pyrogen test] and electron spin resonance (ESR) characteristics were studied at normal (25 °C, 60% relative humidity) and accelerated (40 °C, 75% relative humidity) stability test conditions.

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Abstract  

Airborne concentration levels of222Rn and its progeny, and220Rn progeny were measured in an underground U mine. In addition, concurrent measurements of several meteorological variables such as temperature, relative humidity, barometric pressure and airflow rate were also carried out. Mining operations and mining activities during the measurements were carefully noted. The data collected show great variability. Although not particularly strong, some definite correlations could be found between airborne radioactivity concentration levels, meteorological variables, and mining operations (and mining activities). The difficulty in obtaining stronger correlations between the above variables is attributed to the great and simultaneous variability of most of the variables measured. The data presented here are typical of active U–Th mining environments, i.e., of Ontario (Canada) underground U mines. Measurements extended for a period of a full calendar year and involved several thousand independent measurements.

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Abstract  

A method is proposed which, through the monitoring and modeling of the diurnal variation of α-radioactivity in the air near the ground, appears with a potential in enhancing the measurement of low radioactivity unexpected peaks over the natural background. Portable field instrumentation was used for the monitoring which further included the total γ-radiation at ground level, the relative humidity and temperature. The variation of the α-radioactivity follows a periodic form with peaks in the morning and in the afternoon. The applicability of a mathematical model to describe this variation of the α-radioactivity in terms of the meteorological variables and the γ-radiation was tested positive. This could reduce the difference between the measured and modeled periodic variation to an almost flat one, above which sudden unexpected peaks of radioactivity from possible undeclared nuclear activities could be easier identified.

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Thermal properties of polysaccharides at low moisture

II. Molecular order and control of dissolution temperature in agar

Journal of Thermal Analysis and Calorimetry
Authors: D. Cooke, M. J. Gidley, and N. D. Hedges

Differential scanning calorimetry (DSC) has been used to probe ordered structures and glassing behaviour for a range of agars containing < 25% w/w water. Most commercial agars are supplied in an ordered (double-helical) state, show an endothermic helix-to-coil transition above 100‡C at low-moisture, and require 90–100‡C for solubilisation in excess water. Agars dried from the coil (single-chain) state show no corresponding endothermic transitions and only require a minimum of 45‡C for aqueous dissolution. Evidence from helix-to-coil transition enthalpies, equilibrium water content as a function of relative humidity, and solid-state13C NMR spectroscopy suggests that water molecules are associated enthalpically with double-helical agar. Single-chain agar is apparently not obtained in a glassy state by direct drying from solution, but in common with double-helical forms, exhibits rubber/glass transition behaviour following heating (in a DSC pan) to 180‡C.

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Abstract  

Knowledge of the dynamics of HTO in leafy plant–soil system is required to verify models, such as the NORMTRI code, which predict environmental tritium following its release. Tritium concentrations in plants has been evaluated using the code NORMTRI and experimentally by collection of samples of different plants and their soils samples. In the present study, major seasonal crop plants i.e. wheat, mustard, sugar cane, coriander, spinach, potato, were collected beyond Narora Atomic Power Station site boundary and gular, arandi, neem, ashok, amaltas, csuarina leaf samples within NAPS site boundary for analysis of HTO content. Data analysis indicated that HTO in leaf is strongly influenced by atmospheric relative humidity and type of the plant.

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Journal of Thermal Analysis and Calorimetry
Authors: M. Odlyha, Q. Wang, G. M. Foster, J. de Groot, M. Horton, and L. Bozec

Summary  

Dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC) and thermogravimetry (TG) have been used to characterise model tapestries, especially woven for the EC-funded project (MODHT) and to historic tapestries in royal palaces and museums. Modulus values of woollen threads from model tapestries are reported and the effects of traditional dyeing and mordanting processes quantified. TG, particularly of black woollen threads showed alterations in thermal stability. Tests of creep on immersion in water and subsequent heating to 90C and on exposure to a controlled relative humidity programme were also used to rank these effects. Modulus values of historic woollen samples were also obtained and DSC studies of model and historic silk samples are reported together with preliminary atomic force microscopy (AFM) images of silk fibres.

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Abstract

This work deals with the photocatalytic oxidation of toluene at room temperature and atmospheric pressure in the gas phase. The differential equations of the reactor model are solved numerically with simultaneous estimation of the model parameters. Estimation of the kinetic data is performed using a modified differential method of data analysis and a Nelder–Mead method of nonlinear optimization for parameter estimation. The reaction is performed in an annular photoreactor using UVA black light blue fluorescent lamp. The experiments are carried out at different total flow rates of the reaction feed (20–160 cm3 min−1), two different inlet concentrations of toluene (2.67 and 5.24 g m−3) and at constant relative humidity (25%). A good agreement between the experimental data and theoretical predictions is obtained, supporting the applicability of the proposed models to describe the investigated process performed in laboratory annular photoreactor.

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An impact of temperature, light and relative humidity were studied on root colonisation by mycorrhizal fungi and on pine seedling growth. Moderate and high light intensities favoured mycorrhizal colonisation and seedling growth. Pine seedlings inoculated with Pisolithus tinctorius compared to other fungi attained maximum growth. Survival of pine seedlings was higher under moderate light intensity than low and high light intensity. Seedling growth and mycorrhizal colonisation was better at 25°C than 10°C. Variation in humidity did not show much difference in mycorrhizal colonisation and seedling growth. However, seedling survival was greater at high than at low humidity. Pine seedlings showed best survival with 0.5 P level (46.153 mg P/kg soil) of phosphorus at 25 °C temperature and under moderate light intensity. Among the mycorrhizal fungi used P. tinctorius was the most effective endophyte and was followed by Laccaria laccata, Rhizopogon luteolus and Collybia radicata under various physical factors.

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The present paper focuses on the re-evaluation of archive engineering geological data of sic core drillings at one of the new metro stations of Budapest (Kálvin square, metro line 4). More than 1000 data of total coring length of more than 210 meters were used for statistical calculations. The data set includes index of plasticity, skewness, void ratio, water content, dry and water saturated bulk density, relative humidity, angle of friction, cohesion and compressive strength. Based on the data set the engineering geological description of sediments was reevaluated, and sand, clay, silt and bentonite-rich horizons were identified. Three new crosssections were prepared. Statistical analyses proved that there is an increase in cohesion and density of clays and silts with depth, indicating the role of consolidation.

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