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In this paper we introduce differential subordination and superordination properties for certain subclasses of analytic functions involving certain linear operator, and obtain sandwich-type results for the functions belonging to these classes.

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A field experiment was conducted in China during winter season of 2001–2002 to study the response of time of nitrogen application on two cultivars (Xiumei 3 and 92-11) of barley. Apart from basal dose of 40 kg N/ha, 110 kg N/ha was applied at tillering (T 1 ) or in two equal splits at tillering and boot stages (T 2 ) or at boot stage (T 3 ). Cultivar 92-11 attained significantly lower plant height at boot stage and number of spikes/plant but took significantly more number of days to heading, registered significantly more chlorophyll content in leaves at different growth stages, produced significantly more number of grains/spike, grain weight/spike, single grain weight, N concentration at boot stage and consequently produced significantly higher grain yield (3764 kg/ha) than cultivar Xiumei 3 (3201 kg/ha). Application of nitrogen at boot stage significantly reduced the plant height at both stages, dry matter accumulation, days taken to heading, leaf chlorophyll content at boot stage, grains per spike, grain weight per spike and individual grain weight but recorded significantly higher chlorophyll content in leaves at heading stage and higher N content as compared to its application at tillering. Split application of nitrogen at tillering and boot stages also recorded significantly better growth and yield attributes, N concentration and grain yield than its application at boot stage alone but was at par with nitrogen applied at tillering except grain weight per spike. Consequently application of nitrogen at tillering or its split application at tillering and boot stages produced statistically similar (4052 and 3816 kg/ha, respectively) but significantly higher grain yield than its application at boot stage (2500 kg/ha).

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The effect of time of nitrogen application and position of kernels in spike on kernel weight, protein content, β-amylase activity and β-glucan content were examined in two cultivars of barley. Cultivar 92-11 produced significantly bold kernels and lower β-glucan content with slightly lower protein content and higher β-amylase activity than cultivar Xiumei 3. Time of nitrogen application significantly influenced the quality parameters studied. Application of 110 kg N/ha at tillering produced significantly higher kernel weight and significantly lower protein content as well as β-glucan content as compared to its application made at boot stage. β-Amylase activity was also lowest in case of nitrogen applied at tillering stage. There were significant differences between two cultivars for quality parameters when kernels were selected from different spike positions or where specific plant part was removed at heading. The highest 1000-kernel weight was recorded in 92-11 (52.5%) with removal of side tillers and in Xiumei 3 (42.2%) from the middle portion of spike; whereas for protein content, opposite trend was obtained. β-Amylase activity in both cultivars was the highest when middle portion of spike was removed. The lowest β-glucan contents in 92-11 and Xiumei 3 were registered with removal of flag leaf and in Xiumei 3 with the removal of middle portion of spike.

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Journal of Thermal Analysis and Calorimetry
Authors:
Xue-Gang Chen
,
Shuang-Shuang Lv
,
Ping-Ping Zhang
,
Lu Zhang
, and
Ying Ye

Abstract

In this study, we ashed rice hull in air and nitrogen, respectively, and systematically investigated the effects of ashing temperature and atmosphere on the structures, morphologies, and pore characteristics of rice hull ash (RHA). All RHA samples are amorphous materials with porous structures. IR spectra revealed that RHA that ashed in air (WRHA) exhibit more polar groups on the surface than that of ashed in nitrogen (BRHA). The silica and carbon contents, BET surface area, and pore volume of BRHA increase with ashing temperature. When ashed in air, however, the silica content of WRHA increases and carbon content decreases with temperature. The BET surface area and pore volume of WRHA increase with temperature firstly and decline subsequently due to the closure of pores. Compared with WRHA, BRHA shows higher surface areas, micropore volumes, carbon contents, and lower mesopore fractions and silica contents. This study provides essential information for choosing a suitable thermal treatment of rice hull for a given adsorbate.

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Abstract  

To simplify TRPO process, a novel ligand, N,N’-dimethyl-3-oxa-glutaramic acid (DMOGA), was synthesized and used for stripping of An(III, IV) from 30% TRPO-kerosene. The distribution ratios for transuranium elements, including Np(IV), Pu(IV), Am(III), and some fission products, including Eu(III), Fe and Zr between 30% TRPO-kerosene and various HNO3-DMOGA solutions were measured. An(III, IV) and Ln(III) extracted to TRPO from simulated high level liquid waste could be recovered with an efficiency of 99.9% above in one stream with a 3-stage crosscurrent strip experiment with 0.2M DMOGA in HNO3 solution. Using this new agent, the back extraction of TRU elements from loaded TRPO phase becomes more simple and practical. Therefore, the original TRPO process could be simplified.

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Periodica Mathematica Hungarica
Authors:
Peter Buczkowski
,
Gary Chartrand
,
Christopher Poisson
, and
Ping Zhang
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Abstract  

Alkaline earth metal (Mg, Ca, Sr and Ba) ions were exchanged into Hβ zeolite, which were used as the supports to load the noble metal Pt to prepare bifunctional catalysts for hydroisomerization of n-heptane. The catalysts were characterized by ICP, XRD, BET, NH3-TPD, H2-TPR and H2-chemisorption techniques, and evaluated in an atmospheric fixed bed reactor. The catalysts promoted by the alkaline earth metals are revealed to present much higher selectivity to isomerization than the counterpart Pt/Hβ. Moreover, the Ba-bearing catalyst loaded with 0.4 wt% Pt and 5:1 molar ratio of Ba to Pt gives a very high selectivity to iso-heptanes 95.4% with a considerable high conversion of n-heptane 61.7%. The promotion effect of alkaline earth metals is briefly discussed in relation to characterization data.

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Abstract  

Differential elastic scattering cross sections for backscattering of 0.96–2.74 MeV protons incident on an aluminum layer covered by a gold layer deposited on a graphite crystal have been measured. The lowest proton energy in the experiment is in the Rutherford backscattering energy region. The measured cross sections are compared with the previous data and presented in graphical and tabular forms.

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Abstract  

This study characterized the removal of strontium from an aqueous solution via co-precipitation followed by microfiltration (CPMF) on a lab-scale. Sodium carbonate was used as the precipitating agent. Ferric chloride was added to a settler at a dosage of 20 mg/L to improve strontium removal, and it was added to a membrane separator at a dosage of 10 mg/L to reduce membrane fouling. The concentration of strontium in the raw water used in this study was about 5 mg/L. In two intermittent tests, where dosages of sodium carbonate were 2000 mg/L and 1000 mg/L, the mean decontamination factors (DFs) were 237 and 158 and the mean concentration factors (CFs) were 288 and 462, respectively. Although the mean DF value was lower when the sodium carbonate dosage was 1000 mg/L instead of 2000 mg/L, the rate at which the specific flux (SF) of the membrane declined decreased as the amount of the effluent treated increased. The problem of strontium release at the beginning of the operation was controlled by a continuous test in which the dosage of sodium carbonate still was 1000 mg/L and the other parameters were the same as in the other tests. The results showed that the mean DF and CF were 157 and 480, respectively.

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Abstract

Platinum nanoparticles, synthesized via ethanol reduction of hexachloroplatinic acid in the presence of poly-(N-vinyl-2-pyrrolidone), were anchored on magnesium aluminate spinel using a colloidal deposition method. The samples were characterized using the following methods: transmission electron microscopy, powder X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The results revealed that platinum nanoparticles, with an average diameter of 2.8 nm, are homogenously dispersed on the surface of the carrier. Under very mild conditions, supported Pt/MgAl2O4 catalysts demonstrated excellent catalytic activity and high selectivity in the hydrogenation reaction of benzaldehydes to benzyl alcohols. The reaction kinetics for the catalytic hydrogenation of 3-phenoxybenzaldehyde to 3-phenoxybenzyl alcohol on a Pt/MgAl2O4 catalyst can be described by equation , and the apparent activation energy is 35.6 kJ mol−1.

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