Search results for: phosphorus uptake
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 923

Search results for: phosphorus uptake

923 Effects of Molybdenum on Phosphorus Concentration in Rice (Oryza sativa L.)

Authors: Hamed Zakikhani, Mohd Khanif Yusop, Amin Soltangheisi

Abstract:

A hydroponic trial was carried out to investigate the effect of molybdenum (Mo) on uptake of phosphorus (P) in different rice cultivars. The experiment was conducted using a randomized complete-block design, with a split-plot arrangement of treatments and three replications. Four rates of Mo (0, 0.01, 0.1 and 1 mg L−1) and five cultivars (MR219, HASHEMI, MR232, FAJRE and MR253) provided the main and sub-plots, respectively. Interaction of molybdenum×variety was significant on shoot phosphorus uptake (p≤0.01). Highest and lowest shoot phosphorus uptake were seen in Mo3V3 (0.6% plant-1) and Mo0V3 (0.14% plant-1) treatments, respectively. Molybdenum did not have a significant effect on root phosphorus content. According to results, application of molybdenum has a synergistic effect on uptake of phosphorus by rice plants.

Keywords: molybdenum, phosphorus, uptake, rice,

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922 Phosphorus Uptake of Triticale (Triticosecale Wittmack) Genotypes at Different Growth Stages

Authors: Imren Kutlu, Nurdilek Gulmezoglu

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Triticale (Triticosecale Wittmack) is a man-made crop developed by crossing wheat (Triticum L.) and rye (Secale cereale L.). Triticale has until now been used mostly for animal feed; however, it can be consumed by humans in the form of biscuits, cookies, and unleavened bread. Moreover, one of the reasons for the development of triticale is that it is more efficient in nutrient deficient soil than wheat cultivars. After nitrogen fertilizer, phosphorus (P) is the most used fertilizer for crop production because P fixation occurs highly when it is applied the soil. The aim of the present study was to evaluate P uptake of winter triticale genotypes under different P fertilizer rates in different growth stages. The experiment was conducted in Eskisehir, Central Anatolia, Turkey. Treatments consisted of five triticale lines and one triticale cultivars (Samursortu) with four rates of P fertilization (0, 30, 60 and 120 kg P2O5 ha⁻¹). Phosphorus uptake of triticale genotypes in tillering, heading, as well as grain and straw at harvest stage and yield of grain and straw were determined. The results showed that a P rate of 60 kg/ha and the TCL-25 genotype produced the highest yields of straw and grain at harvest. Phosphorus uptake was the highest in tillering stage, and it decreased towards to harvest time. Phosphorus uptake of all growth stage increased as P rates raised and the application of 120 kg/ha P₂O₅ had the highest P uptake. Phosphorus uptake of genotypes was found differently. The regression analyses indicated that P uptake at tillering stage was the most effective on grain yield. These results will provide useful information to triticale growers about suitable phosphorus fertilization for both forage and food usage.

Keywords: grain yield, growth stage, phosphorus fertilization, phosphorus uptake, triticale

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921 Simulation of 'Net' Nutrients Removal by Green Mussel (Perna viridis) in Estuarine and Coastal Areas

Authors: Chayarat Tantanasarit, Sandhya Babel

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Green mussels (Perna viridis) can effectively remove nutrients from seawater through their filtration process. This study aims to estimate 'net' nutrient removal rate by green mussel through calculation of nutrient uptake and release. Nutrients (carbon, nitrogen, and phosphorus) uptake was calculated based on the mussel filtration rate. Nutrient release was evaluated from carbon, nitrogen, and phosphorus released as mussel feces. By subtracting nutrient release from nutrient uptake, net nutrient removal by green mussel can be found as 3302, 380 and 124 mg/year/indv. Mass balance model was employed to simulate nutrient removal in actual green mussel farming conditions. Mussels farm area, seawater flow rate and amount of mussels were considered in the model. Results show that although larger quantity of green mussel farms lead to higher nutrient removal rate, the maximum green mussel cultivation should be taken into consideration as nutrients released through mussel excretion can strongly affect marine ecosystem.

Keywords: carbon, ecretion, filtration, nitrogen, phosphorus

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920 Technologies for Phosphorus Removal from Wastewater: Review

Authors: Thandie Veronicah Sima, Moatlhodi Wiseman Letshwenyo

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Discharge of wastewater is one of the major sources of phosphorus entering streams, lakes and other water bodies causing undesired environmental problem such as eutrophication. This condition not only puts the ecosystem at risk but also causes severe economic damages. Stringent laws have been developed globally by different bodies to control the level of phosphorus concentrations into receiving environments. In order to satisfy the constraints, a high degree of tertiary treatment or at least a significant reduction of phosphorus concentration is obligatory. This comprehensive review summarizes phosphorus removal technologies, from the most commonly used conventional technologies such as chemical precipitation through metal addition, membrane filtration, reverse osmosis and enhanced biological phosphorus removal using activated sludge system to passive systems such as constructed wetlands and filtration systems. Trends, perspectives and scientific procedures conducted by different researchers have been presented. This review critically evaluates the advantages and limitations behind each of the technologies. Enhancement of passive systems using reactive media such as industrial wastes to provide additional uptake through adsorption or precipitation is also discussed in this article.

Keywords: adsorption, chemical precipitation, enhanced biological phosphorus removal, phosphorus removal

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919 How Does Vicia faba-rhizobia Symbiosis Improve Its Performance under Low Phosphorus Availability?

Authors: B. Makoudi, R. Ghanimi, M. Mouradi, A. Kabbadj, M. Farissi, J. J. Drevon, C. Ghoulam

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This work focuses on the responses of Vicia fabarhizobia symbiosis to phosphorus deficiency and their contribution to tolerate this constraint. The study was carried out on four faba bean varieties, Aguadulce, Alfia, Luz Otono, and Reina Mora submitted to two phosphorus treatments, deficient and sufficient and cultivated under field and greenhouse hydroaeroponic culture. Plants were harvested at flowering stage for growth, nodulation and phosphorus content assessment. Phosphatases in nodules and rhizospheric soil were analyzed. The impact of phosphorus deficiency on yield component was assessed at maturity stage. Under field conditions, phosphorus deficiency affected negatively nodule biomass and nodule phosphorus content with Alfia and Reina Mora showing the highest biomass reduction. The phosphatase activities in nodules and rhizospheric soil were increased under phosphorus deficiency. At maturity stage, under soil low available phosphorus, the pods number and 100 seeds weight were reduced. The genotypic variation was evident for almost all tested parameters.

Keywords: faba bean, phosphorus, rhizobia, yield

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918 Impacts of CuO, TiO2, SiO2 Nanoparticles on Biological Phosphorus Removal

Authors: H. Shiu, M.S. Lu, Y.P. Tsai

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This study explored the impacts of CuO, TiO2, SiO2 nanoparticles on biological phosphorus removal. Experimental results showed that the phosphorus removal ability of phosphorus accumulating organism (PAO) was initially inhibited when CuO nanoparticle concentration was 5 mgl-1. The inhibition of phosphorus removal for 1000 mgl-1 of TiO2 with sunlight was higher than without sunlight case. The inhibition of phosphorus removal began at 500 mgl-1 SiO2 nanoparticle concentration. Inhibition became apparent when SiO2 nanoparticle concentration was up to 1000 mgl-1.

Keywords: nano copper oxide, nano titanium dioxide, nano silica, enhanced biological phosphate removal

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917 Carbothermic Reduction of Phosphoric Acid Extracted from Dephosphorization Slags to Produce Yellow Phosphorus

Authors: Ryoko Yoshida, Jyunpei Yoshida, Hua Fang Yu, Yasushi Sasaki, Tetsuya Nagasaka

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Phosphorous is an important element for agriculture and industry and is a non-renewable resource. Especially, yellow phosphorus is an essential material in advanced industrial technology, but phosphorus resources were not produced in Japan at all, and all depend on imports. It has been suggested, however, that the remaining accessible reserves of phosphate ore will be depleted within 50 years. Therefore, alternative resources for phosphate ore must be found. In this research, we have developed a process that enables the production of high-purity yellow phosphorus from domestic unused phosphorus resources such as steelmaking slags. The process consists of two parts: (1) the production of crude phosphoric acid from wastes such as steelmaking slag; (2) producing high-purity yellow phosphorus by low-temperature carbothermic reduction of phosphoric acid (H3PO4). The details of the carbothermic reduction of phosphoric acid are presented in this paper. Yellow phosphorus is commercially produced by carbothermic reduction of phosphate ore in an electric arc furnace at more than 1673K. In the newly developed system, gaseous P4O10 evaporated from H3PO4 is successfully reduced to yellow phosphorus by using carbon packed bed at less than 1273K. To meet the depletion of phosphate ore, the proposed process in this study to produce yellow phosphorus by carbothermic reduction of H3PO4 that are extracted from dephosphorization slags will be one of the effective and economical solutions.

Keywords: carbothermic reduction, phosphoric acid, dephosphorization slags, yellow phosphorus

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916 Nitrogen, Phosphorus, Potassium (NPK) Hydroxyapatite Nano-Hybrid Slow Release Fertilizer

Authors: Tinomuvonga Manenji Zhou, Eubert Mahofa, Tatenda Crispen Madzokere

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The nanostructured formulation can increase fertilizer efficacy and uptake ratio of the soil nutrients in agriculture production and save fertilizer resources. Controlled release modes have properties of both release rate and release pattern of nutrients, for fertilizers that are soluble in water might be correctly controlled. Nanoparticles can reduce the rate at which fertilizer nutrients are in the soil by leaching. A slow release NPK-hydroxyapatite nano hybrid fertilizer was synthesized using exfoliated bentonite as filler material. A simple, scalable method was used to synthesize the nitrogen-phosphorus hydroxyapatite nano fertilizer, where calcium hydroxide, phosphoric acid, and urea were used as precursor material, followed by the incorporation of potassium through a liquid grinding method. The product obtained was an NPK-hydroxyapatite nano hybrid fertilizer. A quantitative analysis was done to determine the percentage of nitrogen, phosphorus, and potassium in the hybrid fertilizer. AAS was used to determine the percentage of potassium in the fertilizer. An accelerated water test was conducted to compare the nutrient release behavior of nutrients between the synthesized NPK-hydroxyapatite nano hybrid fertilizer and commercial NPK fertilizer. The rate of release of Nitrogen, phosphorus, and potassium was significantly lower in the synthesized NPK hydroxyapatite nano hybrid fertilizer than in the convectional NPK fertilizer. The synthesized fertilizer was characterized using XRD. NPK hydroxyapatite nano hybrid fertilizer encapsulated in exfoliated bentonite thus prepared can be used as an environmentally friendly fertilizer formulation which could be extended to solve one of the major problems faced in the global fertilization of low nitrogen, phosphorus, and potassium use efficiency in agriculture.

Keywords: NPK hydroxyapatite nano hybrid fertilizer, bentonite, encapsulation, low release

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915 The Effects of Organic or Inorganic Zinc and Microbial Phytase, Alone or in Combination, on the Performance, Biochemical Parameters and Nutrient Utilization of Broilers Fed a Diet Low in Available Phosphorus

Authors: Mustafa Midilli, Mustafa Salman, Omer Hakan Muglali, Tülay Ögretmen, Sena Cenesiz, Neslihan Ormanci

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This study examined the effects of zinc (Zn) from different sources and microbial phytase on the broiler performance, biochemical parameters and digestibility of nutrients when they were added to broiler diets containing low available phosphorus. A total of 875, 1-day-old male broilers of the Ross 308 strain were randomly separated into two control groups (positive and negative) and five treatment groups each containing 125 birds; each group was divided into 5 replicates of 25 birds. The positive control (PC) group was fed a diet containing adequate concentration (0.45%) of available phosphorus due to mineral premix (except zinc) and feeds. The negative control (NC) group was fed a basal diet including low concentration (0.30%) of available phosphorus due to mineral premix (except zinc) and feeds. The basal diet was supplemented with 0.30% phosphorus and 500 FTU phytase (PH); 0.30% phosphorus and organic zinc (OZ; 75mg/kg of Zn from Zn-proteinate); 0.30% phosphorus and inorganic zinc (IZ; 75 mg/kg of Zn from ZnSO4); 0.30% phosphorus, organic zinc and 500 FTU phytase (OZ + PH); and 0.30% phosphorus, inorganic zinc and 500 FTU phytase (IZ + PH) in the treatment groups 1, 2, 3, 4 and 5, respectively. The lowest value for mean body weight was in the negative control group on a diet containing low available phosphorus. The use of supplementation with organic and inorganic zinc alone or in combination with microbial phytase significantly (P<0.05) increased the digestibility of Zn in the male broilers. Supplementation of those diets with OZ + PH or IZ + PH was very effective for increasing the body weight, body weight gain and the feed conversion ratio. In conclusion, the effects on broilers of diets with low phosphorus levels may be overcome by the addition of inorganic or organic zinc compounds in combination with microbial phytase.

Keywords: broiler, performance, phytase, phosphorus, zinc

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914 Correlation between Vitreoscilla Hemoglobin Gene (Vgb) and Cadmium Uptake in the Heterologous Host Enterobacter Aerogenes in Response to Metabolic Inhibitors

Authors: Khaled Khleifat, Muayyad Abboud, Ahmad Almustafa

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The effect of metabolic inhibitor/uncoupler(s) (CCCP and NaN3) and sulfhydryl reagents (dithiothreitol, 2 mercaptoethanol glutathione) on cadmium uptake was investigated in Enterobacter aerogenes strains. They include a transformed strain bearing the Vitreoscillahemoglobin gene, vgb as well as control strains that lack this transformed gene. The vgb-harboring strains showed better uptake of cadmium than vgb-lacking strains. Under low aeration, there was 2 fold enhancement of Cd+2 uptake in vgb-harboring strains compared with 1.6-fold enhancement under high aeration. The CCCP caused 36, 40 and 58% inhibition in cadmium uptake of parental, pUC9 harboring and VHb expressing cells, respectively. Similarly, the sodium azide exerted 44, 38 and 55% inhibition in Cd+2 uptake of parental, pUC9 harboring and VHb expressing cells, respectively. Less extensive inhibition of Cd+2 uptake in the range of 11 to 39% was observed with sulfhydryl reagents.

Keywords: bacterial hemoglobin, VHb, Cd uptake, biosorption

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913 Soil Macronutrients Sensing for Precision Agriculture Purpose Using Fourier Transform Infrared Spectroscopy

Authors: Hossein Navid, Maryam Adeli Khadem, Shahin Oustan, Mahmoud Zareie

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Among the nutrients needed by the plants, three elements containing nitrate, phosphorus and potassium are more important. The objective of this research was measuring these nutrient amounts in soil using Fourier transform infrared spectroscopy in range of 400- 4000 cm-1. Soil samples for different soil types (sandy, clay and loam) were collected from different areas of East Azerbaijan. Three types of fertilizers in conventional farming (urea, triple superphosphate, potassium sulphate) were used for soil treatment. Each specimen was divided into two categories: The first group was used in the laboratory (direct measurement) to extract nitrate, phosphorus and potassium uptake by colorimetric method of Olsen and ammonium acetate. The second group was used to measure drug absorption spectrometry. In spectrometry, the small amount of soil samples mixed with KBr and was taken in a small pill form. For the tests, the pills were put in the center of infrared spectrometer and graphs were obtained. Analysis of data was done using MINITAB and PLSR software. The data obtained from spectrometry method were compared with amount of soil nutrients obtained from direct drug absorption using EXCEL software. There were good fitting between these two data series. For nitrate, phosphorus and potassium R2 was 79.5%, 92.0% and 81.9%, respectively. Also, results showed that the range of MIR (mid-infrared) is appropriate for determine the amount of soil nitrate and potassium and can be used in future research to obtain detailed maps of land in agricultural use.

Keywords: nitrate, phosphorus, potassium, soil nutrients, spectroscopy

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912 Phosphorus Recovery Optimization in Microbial Fuel Cell

Authors: Abdullah Almatouq

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Understanding the impact of key operational variables on concurrent energy generation and phosphorus recovery in microbial fuel cell is required to improve the process and reduce the operational cost. In this study, full factorial design (FFD) and central composite designs (CCD) were employed to identify the effect of influent COD concentration and cathode aeration flow rate on energy generation and phosphorus (P) recovery and to optimise MFC power density and P recovery. Results showed that influent chemical oxygen demand (COD) concentration and cathode aeration flow rate had a significant effect on power density, coulombic efficiency, phosphorus precipitation efficiency and phosphorus precipitation rate at the cathode. P precipitation was negatively affected by the generated current during the batch duration. The generated energy was reduced due to struvite being precipitated on the cathode surface, which might obstruct the mass transfer of ions and oxygen. Response surface mathematical model was used to predict the optimum operating conditions that resulted in a maximum power density and phosphorus precipitation efficiency of 184 mW/m² and 84%, and this corresponds to COD= 1700 mg/L and aeration flow rate=210 mL/min. The findings highlight the importance of the operational conditions of energy generation and phosphorus recovery.

Keywords: energy, microbial fuel cell, phosphorus, struvite

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911 The Interactions between Phosphorus Leaching and Lime Application in Undisturbed Soil Columns with Different Soil Textures

Authors: Faezeh Eslamian, Zhiming Qi, Michael J. Tate

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Phosphorus losses from agricultural fields through leaching is one of the main contributors to eutrophication of lakes in Quebec as well as North America. The main objective of this study is to evaluate the application of high calcium hydrated lime as a soil amendment in reducing the subsurface transport of phosphorus to water bodies by studying the interactions between phosphorus leaching and lime application in three common agricultural soil textures (sandy loam, loam and clay loam) in Quebec. For this purpose, 6 intact soil columns of 10 cm diameter and 20 cm deep were taken from each of the three different soil textured agricultural fields. Lime (high calcium hydrated lime) was applied to the top 5 cm of half of the intact soil columns while the rest were left as controls. The columns were leached with artificial rainwater in-consecutively at a rate of 3 mm h-1 over a 90-day period. The total amount of water added was equal to the average total rainfall of the region in fall. The leachate samples were collected daily and analyzed for dissolved reactive phosphorus, total dissolved phosphorus, total phosphorus, pH, electrical conductivity, calcium, magnesium, potassium and iron. The results showed that lime was able to significantly reduce dissolved reactive phosphorus concentrations in the leachates by 70 and 40 percent in sandy loam and loam soil columns, respectively, while phosphorus concentration in the clay loam soil leachates were increased by 40 percent. The calcium in lime has P-binding capabilities. Soil chemical properties in sandy and loamy soils can affect phosphorus leaching, whereas, transport mechanisms in clay soils with macropores dominate phosphorus leaching behaviors. The presence of preferential pathways and cracks in the clay soil columns has led to a quick transport of phosphorus through the soil and the less contact time with the soil matrix, therefore, causing less opportunity for P sorption and larger P release. Application of lime to agricultural fields can be considered as a promising measure in mitigating phosphorus loss from sandy loam and loam soils.

Keywords: leaching, lime, phosphorus, soil texture

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910 Butene Catalytic Cracking to Propylene over Iron and Phosphorus Modified HZSM-5

Authors: Jianwen Li, Hongfang Ma, Haitao Zhang, Qiwen Sun, Weiyong Ying

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HZSM-5 zeolites modified by iron and phosphorus were applied in catalytic cracking of butene. N2 adsorption and NH3-TPD were employed to measure the structure and acidity of catalysts. The results indicate that increasing phosphorus loading decreased surface area, pore volume and strong acidity of catalysts. The introduction of phosphorus significantly decreased butene conversion and promoted propylene selectivity. The catalytic performance of catalyst was strongly dependent on the reaction conditions. Appropriate reaction conditions could suppress side reactions and enhance propylene selectivity.

Keywords: butene catalytic cracking, HZSM-5, modification, reaction conditions

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909 An Increase in Glucose Uptake per se is Insufficient to Induce Oxidative Stress and Vascular Endothelial Cell Dysfunction

Authors: Heba Khader, Victor Solodushko, Brian Fouty

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Hyperglycemia is a hallmark of uncontrolled diabetes and causes vascular endothelial dysfunction. An increase in glucose uptake and metabolism by vascular endothelial cells is the presumed trigger for this hyperglycemia-induced dysfunction. Glucose uptake into vascular endothelial cells is mediated largely by Glut-1. Glut-1 is an equilibrative glucose transporter with a Km value of 2 mM. At physiologic glucose concentrations, Glut-1 is almost saturated and, therefore, increasing glucose concentration does not increase glucose uptake unless Glut-1 is upregulated. However, hyperglycemia downregulates Glut-1 and decreases rather than increases glucose uptake in vascular endothelial cells. This apparent discrepancy necessitates further study on the effect of increasing glucose uptake on the oxidative state and function of vascular endothelial cells. To test this, a Tet-on system was generated to conditionally regulate Glut-1 expression in endothelial cells by the addition and removal of doxycycline. Glut-1 overexpression was confirmed by Western blot and radiolabeled glucose uptake measurements. Upregulation of Glut-1 resulted in a 4-fold increase in glucose uptake into endothelial cells as determined by 3H deoxy-D-glucose uptake. Increased glucose uptake through Glut-1 did not induce an oxidative stress nor did it cause endothelial dysfunction in rat pulmonary microvascular endothelial cells determined by monolayer resistance, cell proliferation or advanced glycation end product formation. Increased glucose uptake through Glut-1did not lead to an increase in glucose metabolism, due in part to inhibition of hexokinase in Glut-1 overexpressing cells. In summary, this study demonstrates that increasing glucose uptake and intracellular glucose by overexpression of Glut-1 does not alter the oxidative state of rat pulmonary microvascular endothelial cells or cause endothelial cell dysfunction. These results conflict with the current paradigm that hyperglycemia leads to oxidative stress and endothelial dysfunction in vascular endothelial cells through an increase in glucose uptake.

Keywords: endothelial cells, glucose uptake, Glut1, hyperglycemia

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908 Synergistic Effect of Plant Growth Promoting Bacteria and Arbuscular Mycorrhizal Fungi to Enhance Wheat Grain Yield, Biofortification and Soil Health: A Field Study

Authors: Radheshyam Yadav, Ramakrishna Wusirika

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Plant Growth Promoting Bacteria (PGPB) and Arbuscular Mycorrhizal (AM) Fungi are ubiquitous in soil and often very critical for crop yield and agriculture sustainability, and this has motivated the agricultural practices to support and promote PGPB and AM Fungi in agriculture. PGPB can be involved in a range of processes that affect Nitrogen (N) and Phosphorus (P) transformations in soil and thus influence nutrient availability and uptake to the plants. A field study with two wheat cultivars, HD-3086, and HD-2967 was performed in Malwa region, Bathinda of Punjab, India, to evaluate the effect of native and non-native PGPB alone and in combination with AM fungi as an inoculant on wheat grain yield, nutrient uptake and soil health parameters (dehydrogenase, urease, β‐glucosidase). Our results showed that despite an early insignificant increase in shoot length, plants treated with PGPB (Bacillus sp.) and AM Fungi led to a significant increase in shoot growth at maturity, aboveground biomass, nitrogen (45% - 40%) and phosphorus (40% - 34%) content in wheat grains relative to untreated control plants. Similarly, enhanced grain yield and nutrients uptake i.e. copper (27.15% - 36.25%) iron (43% - 53%) and zinc (44% - 47%) was recorded in PGPB and AM Fungi treated plants relative to untreated control. Overall, inoculation with native PGPB alone and in combination with AM Fungi provided benefits to enhance grain yield, wheat biofortification, and improved soil fertility, despite this effect varied depending on different PGPB isolates and wheat cultivars. These field study results provide evidence of the benefits of agricultural practices involving native PGPB and AM Fungi to the plants. These native strains and AM Fungi increased accumulations of copper, iron, and zinc in wheat grains, enhanced grain yield, and soil fertility.

Keywords: AM Fungi, biofortification, PGPB, soil microbial enzymes

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907 Catalytic Cracking of Butene to Propylene over Modified HZSM-5 Zeolites

Authors: Jianwen Li, Hongfang Ma, Haitao Zhang, Qiwen Sun, Weiyong Ying

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Catalytic cracking of butene to propylene was carried out in a continuous-flow fixed-bed reactor over HZSM-5 catalysts modified by nickel and phosphorus. The structure and acidity of catalysts were measured by N2 adsorption, NH3-TPD and XPS. The results revealed that surface area and strong acid sites both decreased with increasing phosphorus loadings. The increment of phosphorus loadings reduced the butene conversion but enhanced the propylene selectivity and catalyst stability.

Keywords: butene, catalytic cracking, HZSM-5, modification

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906 Phytoremediation of Arsenic-Contaminated Soil and Recovery of Valuable Arsenic Products

Authors: Valentine C. Eze, Adam P. Harvey

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Contamination of groundwater and soil by heavy metals and metalloids through anthropogenic activities and natural occurrence poses serious environmental challenges globally. A possible solution to this problem is through phytoremediation of the contaminants using hyper-accumulating plants. Conventional phytoremediation treats the contaminated hyper-accumulator biomass as a waste stream which adds no value to the heavy metal(loid)s decontamination process. This study investigates strategies for remediation of soil contaminated with arsenic and the extractive chemical routes for recovery of arsenic and phosphorus from the hyper-accumulator biomass. Pteris cretica ferns species were investigated for their uptake of arsenic from soil containing 200 ± 3ppm of arsenic. The Pteris cretica ferns were shown to be capable of hyper-accumulation of arsenic, with maximum accumulations of about 4427 ± 79mg to 4875 ± 96mg of As per kg of the dry ferns. The arsenic in the Pteris cretica fronds was extracted into various solvents, with extraction efficiencies of 94.3 ± 2.1% for ethanol-water (1:1 v/v), 81.5 ± 3.2% for 1:1(v/v) methanol-water, and 70.8 ± 2.9% for water alone. The recovery efficiency of arsenic from the molybdic acid complex process 90.8 ± 5.3%. Phosphorus was also recovered from the molybdic acid complex process at 95.1 ± 4.6% efficiency. Quantitative precipitation of Mg₃(AsO₄)₂ and Mg₃(PO₄)₂ occurred in the treatment of the aqueous solutions of arsenic and phosphorus after stripping at pH of 8 – 10. The amounts of Mg₃(AsO₄)₂ and Mg₃(PO₄)₂ obtained were 96 ± 7.2% for arsenic and 94 ± 3.4% for phosphorus. The arsenic nanoparticles produced from the Mg₃(AsO₄)₂ recovered from the biomass have the average particles diameter of 45.5 ± 11.3nm. A two-stage reduction process – a first step pre-reduction of As(V) to As(III) with L-cysteine, followed by NaBH₄ reduction of the As(III) to As(0), was required to produced arsenic nanoparticles from the Mg₃(AsO₄)₂. The arsenic nanoparticles obtained are potentially valuable for medical applications, while the Mg₃(AsO₄)₂ could be used as an insecticide. The phosphorus contents of the Pteris cretica biomass was recovered as phosphomolybdic acid complex and converted to Mg₃(PO₄)₂, which could be useful in productions of fertilizer. Recovery of these valuable products from phytoremediation biomass would incentivize and drive commercial industries’ participation in remediation of contaminated lands.

Keywords: phytoremediation, Pteris cretica, hyper-accumulator, solvent extraction, molybdic acid process, arsenic nanoparticles

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905 The Use of the Phytase in Aquaculture, Its Zootechnical Interests and the Possibilities of Incorporation in the Aquafeed

Authors: Niang Mamadou Sileye

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The study turns on the use of the phytase in aquaculture, its zootechnical interests and the possibilities of incorporation in the feed. The goal is to reduce the waste in phosphorus linked to the feeding of fishes, without any loss of zootechnical performances and with a decrease of feed costs. We have studied the literature in order to evaluate the raw materials (total phosphorus, phytate and available phosphorus) used by a company to manufacture feed for rainbow trout; to determine the phosphorus requirements for aquaculture species; to determine the requirements of phosphorus for aquaculture species, to determine the sings of lack of phosphorus for fishes; to study the antagonism between the phosphorus and the calcium and to study also the different forms of waste for the rainbow trout. The results found in the bibliography enable us test several Hypothesis of feed formulation for rainbow trout with different raw materials. This simulation and the calculation for wastes allowed to validate two formulation of feed: a control feed (0.5% of monocalcique phosphate) and a trial feed (supplementation with 0.002% of phytase Ronozyme PL and without inorganic phosphate). The feeds have been produced and sent to a experimental structure (agricultural college of Brehoulou).The result of the formulation give a decrease of the phosphorus waste of 28% for the trial feed compared to the feed. The supplementation enables a gain of 2.3 euro per ton. The partial results of the current test show no significant difference yet for the zootechnical parameters (growth rate, mortality, weight gain and obvious conversion rate) between control feed and the trial one. The waste measures do not show either significant difference between the control feed and the trial one, but however, the average difference would to decrease the wastes of 35.6% thanks to the use of phytase.

Keywords: phosphorus, phytic acid, phytase, need, digestibility, formulation, food, waste, rainbow trout

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904 Wasteless Solid-Phase Method for Conversion of Iron Ores Contaminated with Silicon and Phosphorus Compounds

Authors: А. V. Panko, Е. V. Ablets, I. G. Kovzun, М. А. Ilyashov

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Based upon generalized analysis of modern know-how in the sphere of processing, concentration and purification of iron-ore raw materials (IORM), in particular, the most widespread ferrioxide-silicate materials (FOSM), containing impurities of phosphorus and other elements compounds, noted special role of nano technological initiatives in improvement of such processes. Considered ideas of role of nano particles in processes of FOSM carbonization with subsequent direct reduction of ferric oxides contained in them to metal phase, as well as in processes of alkali treatment and separation of powered iron from phosphorus compounds. Using the obtained results the wasteless solid-phase processing, concentration and purification of IORM and FOSM from compounds of phosphorus, silicon and other impurities excelling known methods of direct iron reduction from iron ores and metallurgical slimes.

Keywords: iron ores, solid-phase reduction, nanoparticles in reduction and purification of iron from silicon and phosphorus, wasteless method of ores processing

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903 Bioavailability of Zinc to Wheat Grown in the Calcareous Soils of Iraqi Kurdistan

Authors: Muhammed Saeed Rasheed

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Knowledge of the zinc and phytic acid (PA) concentrations of staple cereal crops are essential when evaluating the nutritional health of national and regional populations. In the present study, a total of 120 farmers’ fields in Iraqi Kurdistan were surveyed for zinc status in soil and wheat grain samples; wheat is the staple carbohydrate source in the region. Soils were analysed for total concentrations of phosphorus (PT) and zinc (ZnT), available P (POlsen) and Zn (ZnDTPA) and for pH. Average values (mg kg-1) ranged between 403-3740 (PT), 42.0-203 (ZnT), 2.13-28.1 (POlsen) and 0.14-5.23 (ZnDTPA); pH was in the range 7.46-8.67. The concentrations of Zn, PA/Zn molar ratio and estimated Zn bioavailability were also determined in wheat grain. The ranges of Zn and PA concentrations (mg kg⁻¹) were 12.3-63.2 and 5400 – 9300, respectively, giving a PA/Zn molar ratio of 15.7-30.6. A trivariate model was used to estimate intake of bioaccessible Zn, employing the following parameter values: (i) maximum Zn absorption = 0.09 (AMAX), (ii) equilibrium dissociation constant of zinc-receptor binding reaction = 0.680 (KP), and (iii) equilibrium dissociation constant of Zn-PA binding reaction = 0.033 (KR). In the model, total daily absorbed Zn (TAZ) (mg d⁻¹) as a function of total daily nutritional PA (mmole d⁻¹) and total daily nutritional Zn (mmole Zn d⁻¹) was estimated assuming an average wheat flour consumption of 300 g day⁻¹ in the region. Consideration of the PA and Zn intake suggest only 21.5±2.9% of grain Zn is bioavailable so that the effective Zn intake from wheat is only 1.84-2.63 mg d-1 for the local population. Overall results suggest available dietary Zn is below recommended levels (11 mg d⁻¹), partly due to low uptake by wheat but also due to the presence of large concentrations of PA in wheat grains. A crop breeding program combined with enhanced agronomic management methods is needed to enhance both Zn uptake and bioavailability in grains of cultivated wheat types.

Keywords: phosphorus, zinc, phytic acid, phytic acid to zinc molar ratio, zinc bioavailability

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902 Macronutrient Accumulation and Partitioning for Six Wheat Genotypes Grown at Contrasting Nitrogen Supply

Authors: E. Chakwizira, D. J. Moot, M. Andrews, E. Teixeira

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Partitioning of macro-nutrients in wheat (Triticum aestivum L.) plant organs have not been extensively studied, particularly for modern genotypes grown under contrasting N supply. Nutrient accumulation and partitioning of phosphorus, potassium, calcium, magnesium and sulphur (P, K, Ca, Mg and S) were determined for six wheat genotypes [12S2-2021, 12S3-3019, 13S3-2026, Discovery, Duchess and Reliance] grown with (200 kg/ha) or without (0 kg/ha) nitrogen (N), in a fully irrigated field experiment in 2017-18 season at Lincoln, New Zealand. Data were collected at three growth stages (GS): tillering (GS21), anthesis (GS60) and grain maturity (GS92). Grain yield varied with both N and genotype; from 6-7.5 t/ha for the 0 kg N/ha crops and 8.1-9.3 t/ha for the 200 kg N/ha treatments. Plant nutrient uptake at maturity responded to both N supply and genotype for all nutrients, except S which did not differ among the genotypes. For example, total P uptake averaged 13.5 (12.4-14.3) kg/ha for the 0 kg N/ha treatments and 17.8 (15.1-19.7) kg/ha when 200 kg N/ha was applied. Similarly, K uptake increased from an average of 23 (21.6-25.3) for the 0 kg N/ha treatments to 34.3 (32.4-40.8) kg/ha when 200 kg N/ha was applied. Similar trends were observed for Ca and Mg. The S content only responded to N supply but not to genotype, increasing from 7.9 kg/ha for the 0 kg N treatments to 12.8 kg/ha when 200 kg N was applied. Relative nutrient content at anthesis compared with those at maturity were 30% for P, 100% for both K and Ca and 34% of Mg. Sulphur content at anthesis decreased 29% with N supply and was highest for genotypes 12S2-2021 compared with the other five genotype. At grain maturity, the ratio of nutrients in grain to total plant nutrient, defined as the nutrient harvest index (NHI) varied with both N supply and genotype. Averaged across treatments, the NHI was 0.96 for P, 0.53 for K, 0.58 for Ca, 0.90 for Mg and 0.85 for S. These results suggest that Ca and K should be provided earlier in the season as there is limited or no uptake after anthesis. These results also show that Ca and K are important for structural functions, while P, Mg and S are remobilised to the grains and become important for quality.

Keywords: anthesis, genotype, nutrient harvests index, NHI, Triticum aestivum L.

Procedia PDF Downloads 123
901 Effect of Nitrogen Management on Nitrogen Uptake, Dry Matter Production and Some Yield Parameters

Authors: Mandana Tayefe, Ebrahim Amiri, Azin Nasrollah Zade

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Effect of nitrogen (N) fertilizer levels on nitrogen uptake, dry matter production, yield and some yield components of rice (Hashemi, Kazemi, Khazar) was investigated in an experiment as factorial in RCBD with 3 replications in a paddy light soil at Guilan province, Iran, 2008-2009. In this experiment, four treatments including: N1-control (no N fertilizer); N2- 30 kgN/ha; N3- 60 kgN/ha; N4- 90 kgN/ha were compared. Results showed that total biomass (8386 kg/ha), grain yield (3662 kg/ha), panicles m-2 (235.8) and total grain per panicle (103.8) were reached the highest value at high nitrogen level. Among the varieties the highest total biomass (7734 kg/ha), grain yield (3414 kg/ha) and total grain per panicle (78.2) belonged to Khazar. Dry matter, total N uptake was varied in different cultivars significantly and Khazar variety had the highest contents. Total biomass and total N uptake was varied significantly with the increasement of the amount of nitrogen applied. As total biomass and total N uptake increased with increasing in N fertilizing.

Keywords: rice, nitrogen, nitrogen uptake, dry matter

Procedia PDF Downloads 380
900 Assessing Impacts of Climate Variability and Change on Water Productivity and Nutrient Use Efficiency of Maize in the Semi-arid Central Rift Valley of Ethiopia

Authors: Fitih Ademe, Kibebew Kibret, Sheleme Beyene, Mezgebu Getnet, Gashaw Meteke

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Changes in precipitation, temperature and atmospheric CO2 concentration are expected to alter agricultural productivity patterns worldwide. The interactive effects of soil moisture and nutrient availability are the two key edaphic factors that determine crop yield and are sensitive to climatic changes. The study assessed the potential impacts of climate change on maize yield and corresponding water productivity and nutrient use efficiency under climate change scenarios for the Central Rift Valley of Ethiopia by mid (2041-2070) and end century (2071-2100). Projected impacts were evaluated using climate scenarios generated from four General Circulation Models (GCMs) dynamically downscaled by the Swedish RCA4 Regional Climate Model (RCM) in combination with two Representative Concentration Pathways (RCP 4.5 and RCP8.5). Decision Support System for Agro-technology Transfer cropping system model (DSSAT-CSM) was used to simulate yield, water and nutrient use for the study periods. Results indicate that rainfed maize yield might decrease on average by 16.5 and 23% by the 2050s and 2080s, respectively, due to climate change. Water productivity is expected to decline on average by 2.2 and 12% in the CRV by mid and end centuries with respect to the baseline. Nutrient uptake and corresponding nutrient use efficiency (NUE) might also be negatively affected by climate change. Phosphorus uptake probably will decrease in the CRV on average by 14.5 to 18% by 2050s, while N uptake may not change significantly at Melkassa. Nitrogen and P use efficiency indicators showed decreases in the range between 8.5 to 10.5% and between 9.3 to 10.5%, respectively, by 2050s relative to the baseline average. The simulation results further indicated that a combination of increased water availability and optimum nutrient application might increase both water productivity and nutrient use efficiency in the changed climate, which can ensure modest production in the future. Potential options that can improve water availability and nutrient uptake should be identified for the study locations using a crop modeling approach.

Keywords: crop model, climate change scenario, nutrient uptake, nutrient use efficiency, water productivity

Procedia PDF Downloads 45
899 Development of Soil Test Kits to Determine Organic Matter Available Phosphorus and Exchangeable Potassium in Thailand

Authors: Charirat Kusonwiriyawong, Supha Photichan, Wannarut Chutibutr

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Soil test kits for rapid analysis of the organic matter, available phosphorus and exchangeable potassium were developed to drive a low-cost field testing kit to farmers. The objective was to provide a decision tool for improving soil fertility. One aspect of soil test kit development was ease of use which is a time requirement for completing organic matter, available phosphorus and exchangeable potassium test in one soil sample. This testing kit required only two extractions and utilized no filtration consuming approximately 15 minutes per sample. Organic matter was principally created by oxidizing carbon KMnO₄ using the standard color chart. In addition, modified single extractant (Mehlich I) was applied to extract available phosphorus and exchangeable potassium. Molybdenum blue method and turbidimetric method using standard color chart were adapted to analyze available phosphorus and exchangeable potassium, respectively. Modified single extractant using in soil test kits were highly significant matching with analytical laboratory results (r=0.959** and 0.945** for available phosphorus and exchangeable potassium, respectively). Linear regressions were statistically calculated between modified single extractant and standard laboratory analysis (y=0.9581x-12.973 for available phosphorus and y=0.5372x+15.283 for exchangeable potassium, respectively). These equations were calibrated to formulate a fertilizer rate recommendation for specific corps. To validate quality, soil test kits were distributed to farmers and extension workers. We found that the accuracy of soil test kits were 71.0%, 63.9% and 65.5% for organic matter, available phosphorus, and exchangeable potassium, respectively. The quantitative survey was also conducted in order to assess their satisfaction with soil test kits. The survey showed that more than 85% of respondents said these testing kits were more convenient, economical and reliable than the other commercial soil test kits. Based upon the finding of this study, soil test kits can be another alternative for providing soil analysis and fertility recommendations when a soil testing laboratory is not available.

Keywords: available phosphorus, exchangeable potassium, modified single extractant, organic matter, soil test kits

Procedia PDF Downloads 105
898 Boosting the Agrophysiological Performance of Chickpea Crop (Cicer Arietinum L.) Under Low-P Soil Conditions with the Co-application of Bacterial Consortium (Phosphate Solubilizing Bacteria and Rhizobium) and P-Fertilizers (RP and TSP Forms)

Authors: Rym Saidi, Pape Alioune Ndiaye, Ibnyasser Ammar, Zineb Rchiad, Khalid Daoui, Issam Kadmiri Meftahi, Adnane Bargaz

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Chickpea (Cicer arietinum L.) is an important leguminous crop grown worldwide and plays a significant role in humans’ dietary consumption. Alongside nitrogen (N), low phosphorus (P) availability within agricultural soils is one of the major factors limiting chickpea growth and productivity. The combined application of beneficial bacterial inoculants and Rock P-fertilizer could boost chickpea performance and productivity, increasing P-utilization efficiency and minimizing nutrient losses under P-deficiency conditions. A greenhouse experiment was conducted to evaluate the response of chickpeas to two P-fertilizer forms (RP and TSP) under N2-fixer and P-solubilizer consortium inoculation to improve biological N fixation and P nutrition under P-deficient conditions. Under inoculation, chickpea chlorophyll content and chlorophyll fluorescence (RP+I and TSP+I) were increased compared to uninoculated treatments. The RP+I treatment increased both shoot and root dry weights by 48,80% and 72,68%, respectively, compared to the uninoculated RP fertilized control. Indeed, the bacterial consortium contributed to enhancing root morphological traits (e.g., root volume, surface area, and diameter) of all inoculated treatments versus the uninoculated treatments. Furthermore, soil available P and root inorganic P were significantly improved in RP+I by 162,84% and 73,24%, respectively, compared to uninoculated RP control. Our research outcomes suggest that the co-inoculation of chickpeas with N2-fixing, and P-solubilizing bacteria improves biomass yield and nutrient uptake. Eventually, enhancing chickpea agrophysiological performance, especially in restricted P-availability conditions.

Keywords: chickpea, consortium, beneficial bacterial inoculants, phosphorus deficiency, rock p-fertilizer, nutrient uptake

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897 Effects of Chemical and Biological Fertilizer on, Yield, Nitrogen Uptake and Nitrogen Harvest Index of Rice

Authors: Azin Nasrollah Zadeh

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A factorial experiment was applied to evaluate the effect of chemical and biological fertilizer on yield, total nitrogen uptake and NHI of rice. Four biological treatments including:(M1:no fertilizer),( M2:10 ton/ha cow dung ),(M3:20 ton/ha cow dung) and (M4:5 ton/ha azolla compost) and four chemical fertilizer treatments including: (S1: no fertilizer),(S2:40 kg N /ha),(S3:60 kg N /ha) and ( S4:80 kg N /ha ) were compared. Results showed that highest rate of yield (3387 kg/ha) and total nitrogen uptake (81.4 kg/ha) were reached the highest value at M4. Among the chemical fertilizers the highest grain yield (3373 kg/ha) and total nitrogen uptake (87.7) belonged to highest nitrogen level (S4).Also biological and chemical fertilizers were no significant on Harvest index (NHI). Interaction effect of chemical × biological fertilizers didn't show significant difference between all parameters except of yield, as the most grain yield were obtained in M4S4. So it can be concluded that using of bioilogical fertilizers at appropriate rate and type, considering plant requirement, may improve grain yield, nitrogen uptake and use efficiency in rice.

Keywords: azolla, fertilizer, nitrogen uptake, rice, yield

Procedia PDF Downloads 260
896 Dietary Vitamin D Intake and the Bladder Cancer Risk: A Pooled Analysis of Prospective Cohort Studies

Authors: Iris W. A. Boot, Anke Wesselius, Maurice P. Zeegers

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Diet may play an essential role in the aetiology of bladder cancer (BC). Vitamin D is involved in various biological functions which have the potential to prevent BC development. Besides, vitamin D also influences the uptake of calcium and phosphorus , thereby possibly indirectly influencing the risk of BC. The aim of the present study was to investigate the relation between vitamin D intake and BC risk. Individual dietary data were pooled from three cohort studies. Food item intake was converted to daily intakes of vitamin D, calcium and phosphorus. Pooled multivariate hazard ratios (HRs), with corresponding 95% confidence intervals (CIs) were obtained using Cox-regression models. Analyses were adjusted for gender, age and smoking status (Model 1), and additionally for the food groups fruit, vegetables and meat (Model 2). Dose–response relationships (Model 1) were examined using a nonparametric test for trend. In total, 2,871 cases and 522,364 non-cases were included in the analyses. The present study showed an overall increased BC risk for high dietary vitamin D intake (HR: 1.14, 95% CI: 1.03-1.26). A similar increase BC risk with high vitamin D intake was observed among women and for the non-muscle invasive BC subtype, (HR: 1.41, 95% CI: 1.15-1.72, HR: 1.13, 95% CI: 1.01-1.27, respectively). High calcium intake decreased the BC risk among women (HR: 0.81, 95% CI: 0.67-0.97). A combined inverse effect on BC risk was observed for low vitamin D intake and high calcium intake (HR: 0.67, 95% CI: 0.48-0.93), while a positive effect was observed for high vitamin D intake in combination with low, moderate and high phosphorus (HR: 1.31, 95% CI: 1.09-1.59, HR: 1.17, 95% CI: 1.01-1.36, HR: 1.16, 95% CI: 1.03-1.31, respectively). Combining all nutrients showed a decreased BC risk for low vitamin D intake, high calcium and moderate phosphor intake (HR: 0.37, 95% CI: 0.18-0.75), and an increased BC risk for moderate intake of all the nutrients (HR: 1.18, 95% CI: 1.02-1.38), for high vitamin D and low calcium and phosphor intake (HR: 1.28, 95% CI: 1.01-1.62), and for moderate vitamin D and calcium and high phosphorus intake (HR: 1.27, 95% CI: 1.01-1.59). No significant dose-response analyses were observed. The findings of this study show an increased BC risk for high dietary vitamin D intake and a decreased risk for high calcium intake. Besides, the study highlights the importance of examining the effect of a nutrient in combination with complementary nutrients for risk assessment. Future research should focus on nutrients in a wider context and in nutritional patterns.

Keywords: bladder cancer, nutritional oncology, pooled cohort analysis, vitamin D

Procedia PDF Downloads 50
895 Phosphorus Reduction in Plain and Fully Formulated Oils Using Fluorinated Additives

Authors: Gabi N. Nehme

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The reduction of phosphorus and sulfur in engine oil are the main topics of this paper. Very reproducible boundary lubrication tests were conducted as part of Design of Experiment software (DOE) to study the behavior of fluorinated catalyst iron fluoride (FeF3), and polutetrafluoroethylene or Teflon (PTFE) in developing environmentally friendly (reduced P and S) anti-wear additives for future engine oil formulations. Multi-component Chevron fully formulated oil (GF3) and Chevron plain oil were used with the addition of PTFE and catalyst to characterize and analyze their performance. Lower phosphorus blends were the goal of the model solution. Experiments indicated that new sub-micron FeF3 catalyst played an important role in preventing breakdown of the tribofilm.

Keywords: wear, SEM, EDS, friction, lubricants

Procedia PDF Downloads 251
894 Preparation and Flame-Retardant Properties of Epoxy Resins Containing Organophosphorus Compounds

Authors: Tachita Vlad-Bubulac, Ionela-Daniela Carja, Diana Serbezeanu, Corneliu Hamciuc, Vicente Javier Forrat Perez

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The present work describes the preparation of new organophosphorus compounds with high content of phosphorus followed by the incorporation of these compounds into epoxy resin systems in order to investigate the phosphorus effect in terms of thermal stability, flame-retardant and mechanical properties of modified epoxy resins. Thus, two new organophosphorus compounds have been synthesized and fully characterized. 6-Oxido-6H-dibenz[c,e][1,2]oxaphosphorinyl-phenylcarbinol has been prepared by the addition reaction of P–H group of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide to carbonyl group of benzaldehyde. By treating the phenylcarbinol derivative with POCl3 a new phosphorus compound was obtained, having a content of 12.227% P. The organophosphorus compounds have been purified by recrystallization while their chemical structures have been confirmed by melting point measurements, FTIR and HNMR spectroscopies. In the next step various flame-retardant epoxy resins with different content of phosphorus have been prepared starting from a commercial epoxy resin and using dicyandiamide (DICY) as a latent curing agent in the presence of an accelerator. Differential scanning calorimetry (DSC) has been applied to investigate the behavior and kinetics of curing process of thermosetting systems. The results showed that the best curing characteristic and glass transition temperature are obtained at a ratio of epoxy resin: DICY: accelerator equal to 94:5:1. The thermal stability of the phosphorus-containing epoxy resins was investigated by thermogravimetric analysis in nitrogen and air, DSC, SEM and LOI test measurements.

Keywords: epoxy resins, flame retardant properties, phosphorus-containing compounds, thermal stability

Procedia PDF Downloads 273