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121.
M. Yasin Ashraf Mahnaz Roohi Zafar Iqbal M. Ashraf Münir Öztürk 《Communications in Soil Science and Plant Analysis》2016,47(4):405-413
Addition of cadmium, lead, and cadmium + lead (Cd, Pb, and Cd+Pb) to growth medium leads to a reduction in seed germination, length, fresh and dry biomass of shoots and roots, total chlorophyll, chlorophyll a, chlorophyll b, and soluble proteins in plants. This study was undertaken on two mungbean cultivars (MN-92 and MN-98). Application of these metals in the growth medium reduced the bioabsorption of calcium (Ca), magnesium (Mg), and potassium (K). Concentrations of all the metals were greater in the roots than in the shoots except for K, which was greater in the shoots. Mungbean cultivar NM-98 performed better than NM-92 in response to heavy-metal toxicity. Overall, the metal-induced physiobiochemical changes resulted in reduced growth of both mungbean cultivars. 相似文献
122.
Faisal Mahmood Jacques Wery Sabir Hussain Tanvir Shahzad Muhammed Arslan Ashraf Olivier Therond 《Archives of Agronomy and Soil Science》2016,62(2):217-234
Cropping system models are widely used tools for simulating the growth and development of crops at field scale. However, it is often difficult to satisfy their detailed input and output data requirements for a proper evaluation of model. In this study, expert knowledge data were used as alternative source to fulfil these data requirements. The model was first calibrated for major crops of the studied area and then evaluated for the same crops by using expert knowledge data. Results showed that the model accurately simulated above-ground biomass and grain yield with a relative root mean square error (RRMSE) of 20% and 17%, respectively. On the other hand, simulated results were less satisfactory for N uptake and cumulated evapotranspiration with RRMSE of 27% and 31%, respectively. The model simulated cumulative variables more accurately than dynamic variables. The results of this study suggest that expert knowledge can be used to get data for intermediate variables rarely measured in experiments used for calibration (green leaf area index, actual evapotranspiration, rooting depth) in typical crop management conditions in the region. This approach enables a global and dynamic evaluation of cropping system models when experimental data is unavailable for large heterogeneous areas in a region. 相似文献
123.
Salman Naeem Vijay Baheti Jiri Militky Jakub Wiener Promoda Behera Azeem Ashraf 《Fibers and Polymers》2016,17(8):1245-1255
In this study, impregnation of iron chloride was carried out on needle punched web of waste acrylic fibers, which was subsequently carbonized under layer of charcoal by physical activation in high temperature furnace to produce iron impregnated activated carbon (FeAC). For comparison purpose, one more sample of activated carbon (AC) was prepared without impregnation of iron chloride. Both the webs were carbonized at 1200 °C with no holding time, and characterization of BET surface area, SEM morphology, EDX elemental analysis, XRD crystalline structure was performed. The FeAC web was used as adsorbent for the removal of methylene blue from aqueous solution. The dye removal percentage was investigated at different experimental parameters like different dye concentrations, adsorbent dosage, stirring speed and different pH. The obtained results were analyzed using linear and non-linear forms of Langmuir and Freundlich isotherms and adsorption kinetics (i.e. pseudo first order and pseudo second order model). 相似文献
124.
In this study, viral pathogens associated with nine outbreaks of naturally occurring dairy calf pneumonia in Mashhad area
of Khorasan Razavi province from September 2008 to May 2009 were assessed. Five diseased calves from each farm were chosen
for examination. Acute and convalescent serum samples were taken from calves with signs of respiratory disease. Sera were
analyzed for antibodies to bovine viral diarrhea virus (BVDV), bovine herpesvirus type 1 (BHV-1), bovine respiratory syncytial
virus (BRSV), parainfluenza virus type 3 (PI-3V), and bovine adenovirus-3 (BAV-3) by indirect ELISA kits. Among 42 serum samples
collected at sample 1, seroprevalence values for viruses BHV-1, BVDV, BRSV, PI-3V, and BAV-3 were 61.9% (26), 57.1% (24),
64.2% (27), 90% (38), and 61.9% (26), respectively. Seroconversion to BVDV, BRSV, PI-3V, and BAV-3 occurred in 11.9% (5),
16.6% (7), 26.1% (11), and 21.4% (9) of animals, and 52.3% (22) had generated antibodies against one or more viral infections
at sample 2. In addition, no significant relationship between seroprevalence of BHV-1, BVDV, BRSV, PI-3V, and BAV-3 and dairy
herd size was observed (P > 0.05). According to serological findings, BHV-1, BVDV, BRSV, PI-3V, and BAV-3 are common pathogens of the dairy calf pneumonia
in dairy herds in Mashhad area of Khorasan Razavi province, Iran. 相似文献
125.
Mehdi Heydari Bernard Prévosto Hamid Reza Naji Ali Ashraf Mehrabi David Pothier 《European Journal of Forest Research》2017,136(2):287-305
In seasonally dry environments such as the Zagros woodlands (Iran), severe drought stress and lack of appropriate management practices can cause failure of oak afforestation or reforestation. We investigated the effect of soil properties and burial depth on Persian oak (Quercus brantii Lindl.) establishment in different microhabitats resulting from traditional forest practices. Four microhabitats that were based on forest structure were considered for oak acorn seeding: (1) inside old sprout clumps (ISPC); (2) under the canopy of tall trees (UCTT); (3) outside the canopy of tall trees and sprout clumps; and (4) near recent stumps or sprout clumps. Acorns were seeded at two depths (2 and 5 cm), and seedling survival and growth variables were recorded for 4 years, together with soil chemical and biological attributes. Stepwise discriminant analysis showed that a combination of total soil nitrogen, cation exchange capacity, available phosphorus and potassium, litter depth, microbial quotient, metabolic coefficient, substrate-induced respiration and earthworm abundance was the best variables to characterise the microhabitats. With the exception of pH, bulk density and soil texture, these variables were higher in UCTT and ISPC than in the other microhabitats. Seedling emergence and survival were greater at a seed depth of 5 cm than at 2 cm. Seedling height and shoot, root and leaf biomasses were higher in the UCTT microhabitat compared to the other microhabitats and correlated positively with soil nutrients contents and most of the soil biological variables but negatively with soil bulk density. This study emphasised the role of microhabitats in creating a “canopy effect” producing favourable physical, chemical and biological soil conditions. In particular, large oak trees form islands of fertility and therefore are of key importance for successful seedling establishment in forests subjected to intense human activities. 相似文献
126.
Muhammad Azeem Ashraf Jakub Wiener Assad Farooq Jana Saskova Muhammad Tayyab Noman 《Fibers and Polymers》2018,19(8):1735-1746
Maghemite glass fibre nanocomposite with excellent magnetic and adsorption properties was successfully developed from nontoxic and eco-friendly reagents by thermal decomposition approach. The developed nanocomposite was utilized in adsorption of methylene blue which follows Freundlich adsorption isotherm. The excellent value of adsorption capacity (51.31 mg g-1) as compared to other adsorbents recommends its potential role for adsorption phenomenon in multiple applications. The developed nanocomposite can be recycled and reused easily. Surface and other functional characteristics of developed nanocomposite were determined through scanning electron microscopy, X-ray diffraction, raman spectroscopy, energy dispersive X-ray spectroscopy and vibrating sample magnetometer. The obtained results revealed that maghemite glass nanocomposite is a potential tool that can be utilized in waste water treatments. 相似文献
127.
Hoagland's nutrient solution of 0, 25, 50, or 75% strength with or without soil-applied nitrogen, phosphorus, and potassium (NPK) fertilizers were sprayed at 7, 14, and 21 days after emergence on two cultivars (AZRI-2006 and NIAB-2011) of mung bean (Vigna radiata (L.) Wilczek). Hoagland's nutrient solution of 75% strength with soil-applied NPK fertilizers markedly increased the growth and yield of mung bean cultivars if applied at 21 days after crop emergence. However, 75% strength Hoagland's nutrient solution without soil-applied NPK fertilizers was comparable to 0, 25, and 50% strengths without NPK fertilizers. Foliar application of 75% strength of Hoagland's nutrient solution with soil-applied NPK fertilizers might enhance the yield of mung bean in low fertile areas. Performance of NIAB-2011 was superior to the other cultivar. It is concluded that Hoagland's nutrient solution of 75% strength can be sprayed at 21 days after emergence to get better yield of mung bean. 相似文献
128.
Muhammad Naeem Muhammad Shahbaz Naeem Rashid Ahmad Muhammad Zahid Ihsan Muhammad Yasin Ashraf Yasir Hussain 《Archives of Agronomy and Soil Science》2018,64(1):116-131
Water and nutrient restrictions are the factors that limiting growth of maize in arid/semi-arid climate. Calcium (Ca2+) uptake is affected severely under drought stress (DS). The objectives of this study were to investigate the effects of DS and foliar applied Ca2+ on growth, physiological, biochemical, yield and grain-nutrient content in two maize cultivars i.e. drought-tolerantDekalb-6525 and drought-sensitive Yousafwala-hybrid. The study comprised of two phases; firstly the best rate of Ca2+ (20, 40 and 60 mg L?1) was evaluated. Secondly, optimized rate of Ca2+ (40 mg L?1) was used to assess physio-biochemical and yield responses of maize under DS. The applied DS caused significant reduction in maize growth, water-status, photosynthesis and grain nutrient contents. Foliar Ca2+ markedly improved plant growth, water-potential (18%), turgor-potential (75%), photosynthesis (45%), stomatal-conductance (47%), transpiration rate (43%) and accumulation of total soluble sugars (20%) along with decline in H2O2 content (23%) in both cultivars under DS. Furthermore, optimized rate of Ca2+ improved maize grain yield and quality under water-deficit conditions. Cultivar Dekalb-6525 presented significant response to Ca2+ over Yousafwala-hybrid. Results of the study surmise that foliar supply of Ca2+ is an effective approach to make plants vigorous to thrive under limited-water supply. 相似文献
129.
Optimizing the manufacturing conditions of veneer strand-flanged I-beams was continued in this study and focused on the strand
density and preparation method. Three levels of strand density were used, while the strands were prepared by either saw or
roll-press splitter. The main results indicated that: within the compaction ratios (1.4–2.3) investigated in this study, the
strand with lower density showed slight improvement in the dimensional stability and the bond strength between web and flange,
but not in bending properties of the I-beams. The strand preparation method was concluded to be dependent on species for akamatsu,
sugi, and bamboo strands; roll-press splitter-prepared strands tended to negatively affect dimensional stability and mechanical
properties of the I-beams. When using akamatsu or sugi strands, low density allowed the possibility of using lower resin application
rates between strands.
Part of this paper was presented at the 54th Annual Meeting of the Japan Wood Research Society in Sapporo, August 2004 相似文献
130.
Ashraf Samy El‐Shahway Mahmoud M. A. Mahmoud Theophilus K. Udeigwe 《Land Degradation \u0026amp; Development》2016,27(2):231-238
Changes in soil chemical properties resulting from continuous rice (Oryza sativa) cultivation on the Nile Delta soils of Egypt were examined. The eight soil profiles characterized for this study were designated as 0 (crop rotation without rice), 1 (crop rotation with rice after every 2 years), and 2, 3, 4, 5, 6, and 7 representing continuous rice cultivation for 2, 4, 8, 12, 15, and 20 years, respectively. Sampling was conducted at 0–20, 20–40, 40–60, and 60–80 cm depths for each profile and samples analyzed for a suite of chemical properties. Soil pH, salinity indicators [electrical conductivity (EC), and exchangeable sodium percentage (ESP)], as well as soluble and exchangeable cations and anions such as chloride and sulfate, all tended to decrease with years of continuous rice cultivation, with a number of significant (p < 0·05) differences observed. Cation exchange capacity (CEC) increased with years of continuous rice cultivation, with a 12% increase observed between 2‐ and 20‐year continuous rice cultivation systems. Principal component analysis conducted on soil properties within the continuous rice cultivation systems (profiles 2–7) revealed two possible components, namely F1 (pH, EC, ESP, and soluble Na+, Mg2+, K+, Cl−, and SO4−2) and F2 (clay, organic matter, and CEC), which could be broadly associated to soil salinity and soil fertility, respectively. Findings suggested possible alterations in soil chemical properties by continuous rice cultivation practices on these Nile Delta soils of Egypt, Africa. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献