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51.
Djordje Grujcic Milanka Drinic Iva Zivanovic Ismail Cakmak Bal Ram Singh 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(4):301-310
Maize (Zea mays L.) is the most widely grown crop in Bosnia and Herzegovina especially in Northwest part of the country. Considering that, the maize is extremely sensitive to micronutrient deficiency the main aim of this study was to asses: (1) micronutrient availability in soil, (2) micronutrient status in silage maize; and (3) the relationship between micronutrient soil availability and maize plant concentration. Soil samples for micronutrient availability (n?=?112) were collected from 28 farms in 7 municipalities. Plant available micro- and macro- nutrients in soil were extracted using Mehlich-3, except plant available Se was extracted using 0.1M KH2PO4. Result showed that on average there was no significant difference between different soil types regarding their potential in plant available nutrients. P deficiency was present both, in soil and plants in whole region. Soil extractable P was ranging from 0.003–0.13?g?kg?1 and total plant P was ranging from 0.79–4.95?g?kg?1. Zinc deficiency was observed in two locations both in soil (0.71?mg?kg?1; 0.79?mg?kg?1) and plant (11.5?mg?kg?1; 15.8?mg?kg?1). Potential Se soil deficiency was observed on some locations, while Se plant status is not high enough to meet daily requirements of farm animals. Extractable soil nutrients could be used as relatively good predictor of potential soil and plant deficiencies, but soil nutrient interactions and climate conditions are highly effecting the plant uptake potential. 相似文献
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Effects of commonly used disinfectants on bacterial load,hatchability and survival of Bluefin Sea bream (Sparidentex hasta) eggs 下载免费PDF全文
The efficacy of four chemical reagents, iodophor, formalin, hydrogen peroxide and bronopol as fish egg surface disinfectants were evaluated in bluefin sea bream (Sparidentex hasta). Fertilized eggs were counted and subjected to a static bath dip treatment in different concentrations of the above chemicals for 4 min before being incubated at 20 ± 0.5°C for 40 h. Treatment efficacy of the different disinfectants was evaluated by assessing the bactericidal activity, egg hatch percentage and survival of larvae up to 3 days post hatch. Results showed that iodophor at medium concentrations (75 and 100 ppm) was the best of all tested disinfectants in bacterial killing ability (12% reduction in the bacterial counts), egg hatching per cent (99.8% and 99.6% respectively) and larval survival up to 3 days post hatch (50.8% and 54.8% respectively). Formalin was the second best disinfectant at levels of 100 and 150 ppm. Hydrogen peroxide gave good results compared with the control while, bronopol showed discouraging results. In conclusion, iodophor appeared to be suitable for bluefin sea bream eggs disinfection with a 4 min exposure to 75–100 ppm when applied 14–16 h after egg fertilization. 相似文献
55.
Erkut Turan Yelda Ozsunar Ismail Gokce Yildirim 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(1):77-80
The aim of this study was to determine the course of the median nerve and its adjacent structures in the carpal canals of 8 healthy dogs by using high-frequency transducers. Before performing ultrasonography, the transverse and posteroanterior diameters as well as the perimeter of the carpus were measured at just proximal to the side of the carpal pad. The anatomical structures were then determined at two levels of the carpal canal, which were named the proximal and distal levels, on the transverse sonograms. The cross-sectional areas, perimeters and the transverse and posteroanterior diameters of the median nerve were measured at these levels. Although all the measurements were larger at the proximal level, significant differences between the proximal and distal levels were determined for the cross-sectional area, the perimeter and the transverse diameter of the median nerve. On the transverse sonogram, the deep digital flexor tendon was seen in almost the center of the carpal canal like a comma shape and also it had a small concavity on the caudal side. The superficial digital flexor tendon was seen as an ovoid shape on the transverse sonograms and it was located nearly at the posterior side of the carpal canal. Both tendons were seen as intermediate-grade echogenic structures. The median artery was located inside of the concavity of the deep digital flexor tendon. Also, the median nerve was seen at the posteromedial side of the median artery. As a result of this study, the cross-sectional areas of the median nerve ranged between 1.01-2.68 mm2 at the proximal level and between 0.93-1.91 mm2 at the distal level. 相似文献
56.
Structural transformation from a linear chain structure to crosslinked chain structure, occuring during the thermal stabilization
stage of carbon fiber manufacture, was followed through the use of infrared spectroscopy, differential scanning calorimetry
(DSC), elemental analysis and gel-fraction measurements. The results obtained from the analysis of IR spectroscopy showed
the gradual and continuous loss of intensity of the nitrile (C≡N) vibration at 2242 cm−1 closely associated with the cyclization reactions whereas the intensity loss of the methylene (CH2) groups vibration around 2920–2939 cm−1 has been attributed to the loss of hydrogen atoms as part of the dehydrogenation reactions. The dehydrogenation index, evaluated
using the absorbance ratio of A1452/A1368, also indicated the gradual loss of hydrogens in agreement with decreasing hydrogen content with progressing stabilization
process. IR spectroscopy also showed the emergence of new absorption bands attributed to the formation of crosslinked ladder-like
structure in the 1590–1600 cm−1 region. The amount of newly formed crosslinked structure was characterized using DSC conversion index, IR conversion index
and gel-fraction measurements. The results are compared and discussed in detail. 相似文献
57.
Structural transformations taking place during the thermal stabilization of polyacrylonitrile (PAN) fiber used for the production
of carbon fiber were characterized using a combination of polarized infrared spectroscopy, thermogravimetric analysis (TGA),
scanning electron microscopy (SEM), and density measurements. Direct relationship between the increasing oxygen content and
the density values was confirmed with increasing stabilization time. Linear density values were found to be directly influenced
by the stabilization time. Thermal stability of stabilized precursor fibers was evaluated in terms of weight loss and residual
weight fraction. The results showed that a residual weight fraction of 65 % at 1000 °C can be obtained but longer stabilization
time resulted in a loss of residual weight fraction due to excessive thermal degradation. SEM was used for the observation
of surface morphological features of stabilized precursor fibers. Polarized infrared spectroscopy showed the loss of molecular
orientation of methylene (CH2), nitrile (Ct=N), and carbonyl (C=O) groups in direct response to the effects of cyclization, dehydrogenation, and amorphization
(i.e. decrystallization) processes taking place during the stabilization stage. 相似文献
58.
Abdullahi Iliyasu Zainal Abidin Mohamed Mohd Mansor Ismail Amin Mahir Abdullah Salleh Mohamed Kamarudin Hashim Mazuki 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):221-247
Most research works on the production frontier in aquaculture focus on efficiency measurement using either Stochastic Production Frontier (SPF) or Data Envelopment Analysis (DEA). The studies on productivity growth in aquaculture were limited, perhaps due to lack of time-series data. Nevertheless, total factor productivity analysis (TFP) in fish farms has started gaining popularity in recent years. In addition, the majority of the efficiency studies have centered on technical efficiency analysis but substantial increases in the output levels can be fully realized through improving overall economic efficiency. Therefore, this review suggests that future research should estimate all three efficiency indices (i.e., technical, allocative and economic efficiencies). 相似文献
59.
Insect reproduction may be affected by a number of factors including seasonal changes in larval or adult nutrition. The effect
of season on the reproductive potential ofMonochamus galloprovincialis (Olivier) females reared inPinus sylvestris L. (Scots pine) logs was investigated by constructing fertility tables for each log that differed only in the season they
were cut. Population parameters were compared among three seasonal cohorts. The intrinsic rate of increase and most of the
associated population parameters of beetles that emerged from logs cut during spring were higher than for beetles emerged
from summer and autumn logs. Slight differences were found between summer and autumn cohorts. We suggest that seasonal differences
in the nutritional quality of logs caused differences inM. galloprovincialis survival and reproductive potential.
http://www.phytoparasitica.org posting March 16, 2008. 相似文献
60.
Roziana Kamaludin Mohd Hafiz Dzarfan Othman Siti Hamimah Sheikh Abdul Kadir Ahmad Fauzi Ismail Mukhlis A. Rahman Juhana Jaafar 《Water, air, and soil pollution》2018,229(11):363
Bisphenol A (BPA) and reactive black 5 (RB5) dye are among the most persistent and non-biodegradable contaminants in water which require an urgent need for the development of effective removal method. The ubiquitous existence of both contaminants could interfere with the human health and aquatic environmental balance. Photocatalytic process as one of advanced oxidation processes (AOPs) has shown high performance for degradation of organic compounds to the harmless materials under sensible condition. Therefore, this study aims to develop a visible-light-driven photocatalyst that can efficiently degrade BPA and RB5 present in household water. N-doped TiO2 were successfully synthesized via simple and direct sol–gel method. The prepared TiO2 nanoparticles were characterized by field emission scanning microscope (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and Brunauere Emmette Teller (BET) analysis. The incorporation of nitrogen in TiO2 lattice exhibited excellent optical responses to visible region as revealed by UV–Vis–NIR spectroscopy absorption capability at 400–600 nm. The photocatalytic activity of the N-doped TiO2 nanoparticles was measured by photocatalytic degradation of BPA and RB5 in an aqueous solution under visible-light irradiations. Degradation of BPA and RB5 was 91.3% and 89.1%, respectively after 360 min illumination. The degradation of BPA and RB5 by N-doped TiO2 was increased up to 89.8% and 88.4%, respectively under visible-light irradiation as compared to commercial TiO2 P25. This finding clearly shows that N-doped TiO2 exhibits excellent photocatalytic degradation of BPA and RB5 under visible irradiation, hence have a promising potential in removing various recalcitrant contaminants for water treatment to fulfill the public need to consume clean water. 相似文献