scholarly journals Preparation and Characterization of Environmentally Friendly Controlled Release Fertilizers Coated by Leftovers-Based Polymer

Processes ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 417 ◽  
Author(s):  
Cong Jia ◽  
Panfang Lu ◽  
Min Zhang
Keyword(s):  
Controlled Release ◽  
Chemical Structure ◽  
Nutrient Release ◽  
Environment Friendly ◽  
Structure Surface ◽  
Agricultural Applications ◽  
Coated Urea ◽  
Microstructure Morphology ◽  
Controlled Release Fertilizers

In this work, a novel bio-based polyurethane (PU) was synthesized by using a leftovers (SF)-based polyol and isocyanate for controlled release fertilizers (CRFs). Its chemical structure, surface elemental compositions and distribution were examined by Fourier transform infrared (FTIR), energy dispersive spectroscopy (EDX) and a multifunctional imaging electron spectrometer (XPS). The microstructure morphology of CRFs were examined by SEM. The nutrient release behaviors of CRFs were observed in water. The results demonstrated that SF-based PU-coated urea (FPU) had a denser structure and better nutrient releasing ability. Findings from this work indicated that the use of SF as a coating material of environment-friendly CRFs had great potential, and would hopefully be used for horticultural and agricultural applications.

Optimization and characterization of flavonoids extracted from Cannabis sativa fibers

2021 ◽  
pp. 004051752110277
Author(s):  
Qilu Cui ◽  
Jiawei Li ◽  
Chongwen Yu
Keyword(s):  
Chemical Structure ◽  
Cannabis Sativa ◽  
Ethanol Concentration ◽  
Extraction Process ◽  
Test Results ◽  
Hemp Fiber ◽  
Hemp Fibers ◽  
Structure Surface ◽  
Degumming Process

In this paper, the extraction process of flavonoids from hemp fibers was studied. Response surface methodology (RSM) analysis of the extraction parameters indicated that optimized results would be ethanol concentration 76 vol.%, bath ratio 1:50, and reaction time 139 min; therefore, an optimal extraction rate of flavonoids of 0.2275% can be obtained. The chemical structure, surface morphology and element composition of flavonoid extracts were analyzed. The test results indicated that hemp extract contains flavonoids, which can be used to extract flavonoids from hemp fiber, so as to comprehensively develop hemp fiber and reduce the discharge of waste liquid in the traditional degumming process.

scholarly journals Soil solution and plant nitrogen on irrigated rice under controlled release nitrogen fertilizers

2017 ◽  
Vol 48 (1) ◽  
Author(s):  
Thais Antolini Veçozzi ◽  
Rogério Oliveira de Sousa ◽  
Walkyria Bueno Scivittaro ◽  
Cristiano Weinert ◽  
Victor Raul Cieza Tarrillo
Keyword(s):  
Controlled Release ◽  
Rice Field ◽  
Nutrient Release ◽  
Nitrogen Fertilizers ◽  
Irrigated Rice ◽  
Plant Nitrogen ◽  
Coated Urea ◽  
Use Efficiency ◽  
Polymer Coated Urea ◽  
N Use

ABSTRACT: A study was conducted to evaluate the solubilization and nitrogen (N) use efficiency (NUE) of controlled release nitrogen fertilizers in irrigated rice, compared to urea. It was developed under semi-controlled conditions, including five treatments: Control, Splitted Urea (pre-sowing and topdressing), Pre-sowing urea, and Polymer Coated Urea (PCU) with 60-day and 90-day release. PCUs did not maintain high NH4 + and NO3 - levels in solution over a longer period than urea. NUE of PCUs was similar to uncoated urea, not increasing nutrient release in irrigated rice field.

scholarly journals Plant Growth and Leachate Electrical Conductivity and pH as Influenced by Controlled-release Fertilizer Blends and Coating Technologies

2017 ◽  
Vol 27 (5) ◽  
pp. 639-643 ◽  
Author(s):  
Carey Grable ◽  
Joshua Knight ◽  
Dewayne L. Ingram
Keyword(s):  
Trace Elements ◽  
Controlled Release ◽  
Polymer Coating ◽  
Ornamental Plants ◽  
Nutrient Release ◽  
Dry Weight ◽  
Polymer Coatings ◽  
Release Rates ◽  
Shoot Dry Weight ◽  
Controlled Release Fertilizers

Although controlled-release fertilizers (CRFs) have been used in container-grown ornamental plants for decades, new coating technologies and blends of fertilizers coated for specific release rates are being employed to customize fertility for specific environments and crops. A study was conducted in the transitional climate of Kentucky to determine the nutrient release rates of three controlled-release blends of 8- to 9-month release and growth response of ‘Double Play Pink’ japanese spirea (Spiraea japonica) and ‘Smaragd’ arbovitae (Thuja occidentalis). Fertilizer 1 (16N–3.5P–8.3K–1.8Mg + trace elements) and Fertilizer 2 (18N–3.1P–8.3K–1.8Mg + trace elements) were prototype blends with different experimental polymer coatings. Fertilizer 3 was a blend of 18N–2.2P–6.6K–1.1Ca–1.4Mg–5.8S + trace elements, which combined 100% resin-coated prills with a polymer coating. Fertilizer 4 was commercially available 15N–3.9P–10K–1.3Mg–6S + trace elements. Fertilizer 3 released its nutrients earlier in the 12-week study than the other three fertilizers and resulted in lower shoot dry weight in both species. The new polymer coating technologies show promise for delivering a predicted release rate and are appropriate for container production of these woody shrubs in Kentucky. An interesting side note of this experiment was that leachate pH measurements across treatments averaged 1.2 units lower for arbovitae (6.3) than for japanese spirea (7.5) at week 12. It was assumed that chemical and/or biological reactions at the root/substrate interface in arbovitae moderated pH increases over the study.

scholarly journals Nitrogen Release Properties of Controlled-release Fertilizers during Tomato Production

HortScience ◽  
2014 ◽  
Vol 49 (12) ◽  
pp. 1568-1574 ◽  
Author(s):  
Luther C. Carson ◽  
Monica Ozores-Hampton ◽  
Kelly T. Morgan ◽  
Jerry B. Sartain
Keyword(s):  
Controlled Release ◽  
Nonlinear Regression ◽  
Nutrient Release ◽  
Nitrogen Release ◽  
Data Logger ◽  
Tomato Crop ◽  
Tomato Production ◽  
N Release ◽  
Soil Temperatures ◽  
Controlled Release Fertilizers

Determination of nutrient release duration from controlled-release fertilizers (CRFs) or soluble fertilizers encapsulated in polymer, resin, or sulfur covered fertilizer coated with a polymer differs among manufacturers, but may be determined as 75% to 80% nitrogen (N) release at a constant temperature (e.g., 20 to 25 °C). Increases or decreases in temperature compared with the manufacturer release determination temperature increase or decrease CRF N release; thus, coated fertilizer may release more rapidly than stated during the fall season when soil temperatures in seepage-irrigated tomato (Solanum lycopersicum) production can reach 40.1 °C. The objectives of this study were to evaluate N release duration of CRFs by measuring N release from CRFs incubated in pouches under polyethylene mulch-covered raised beds and to determine the CRF duration suitable for incorporation into a fall tomato fertility program. In 2011 and 2013, 12 and 14 CRFs from Agrium Advanced Technologies, Everris, Florikan, and Chisso-Asahi Fertilizer were sealed in fiberglass mesh pouches (12.7 × 14 cm) that were buried 10 cm below the bed surface in a tomato crop grown using commercial production practices. A data logger collected soil temperature 10 cm below the bed surface. Pouches were collected and N content was measured eight times through two fall seasons. A nonlinear regression model was fit to the data to determine N release rate. During the 2011 and 2013 seasons, minimum, average, and maximum soil temperatures were 21.2 and 19.2, 25.7 and 23.5, and 32.2 and 27.7 °C, respectively. Seasonal total CRF N release was between 77.6% and 93.8% during 2011 and 58.3% and 94.3% in 2013. In 2011, PCU90 and in 2013, PCU90 and PCNPK120 had the highest seasonal total percentage N release (PNR) and FL180 had the lowest in both years. A nonlinear regression fit N release from CRF with R2 = 0.85 to 0.99 during 2011 and 0.49 to 0.99 during 2013. Nitrogen release from all CRFs was faster than the manufacturer’s stated release, probably as a result of high fall bed temperatures. A CRF or CRF mixture containing CRFs of 120- to 180-day release duration may be recommended, but the CRFs must release greater than 75% N during the season.

scholarly journals 372 Nitrogen and Phosphorus Release from Controlled-release Fertilizers while Overwintering Nursery Stock under Plastic

HortScience ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 456D-456
Author(s):  
Andrew Ristvey ◽  
John Lea-Cox
Keyword(s):  
Controlled Release ◽  
Variable Temperature ◽  
Nutrient Release ◽  
Phosphorus Release ◽  
Early Spring ◽  
Late Winter ◽  
Nitrogen And Phosphorus ◽  
Major Loss ◽  
Few Data ◽  
Controlled Release Fertilizers

Nutrient release patterns from several different controlled-release fertilizers (CRF) were studied during the overwintering period of a long-term nutrient uptake, leaching, and loss study of Azalea (Rhododendron) cv. `Karen' and Holly (Ilex cornuta) cv. `China Girl', under sprinkler and drip irrigation. In Maryland, diurnal winter temperatures can vary from ≈10 °C to above 15 °C. Most growers, therefore, cover frames with opaque plastic for cold protection from November through April. This is also the period when many growers apply CRFs on those plant species that take more than 1 year to produce. Few data are presently available on the release patterns of CRFs under variable temperature conditions in late winter/early spring. We hypothesized that substrate temperatures warmer than 15–16 °C will result in CRFs releasing nutrients at a time when root systems are inactive, with a major loss of nutrients with the first few irrigations in Spring. This 105-day study quantified nitrogen (N) and phosphorus release patterns from four brands of CRF (Osmocote, Nutricote, Scotts High N, and Polyon) with 270- and 360-day release rates, under these conditions. Each CRF was top dressed onto blocks of 18-month-old holly or azalea (n = 112) in 11.5-L (3-gal) containers, at a (low) rate of 6.1 g N per container. Ten randomly selected pots from each treatment were sampled every 15 days using two sequential leachings of distilled water, for a target leaching fraction of 25%. Leachates were recovered and analyzed for nitrate and orthophosphate concentrations. Ambient canopy temperatures were recorded continuously with remote temperature (HoBo) sensors from which degree days above 15–16 °C were calculated and correlated with CRF release patterns.

scholarly journals Nutrient Release from Controlled-release Fertilizers in Acid Substrate in a Greenhouse Environment: I. Leachate Electrical Conductivity, pH, and Nitrogen, Phosphorus, and Potassium Concentrations

HortScience ◽  
2006 ◽  
Vol 41 (3) ◽  
pp. 780-787 ◽  
Author(s):  
Donald J. Merhaut ◽  
Eugene K. Blythe ◽  
Julie P. Newman ◽  
Joseph P. Albano
Keyword(s):  
Electrical Conductivity ◽  
Controlled Release ◽  
Nutrient Release ◽  
Low Fertility ◽  
Plant Production ◽  
Production Cycle ◽  
Permissible Levels ◽  
Phosphorus And Potassium ◽  
Acid Substrate ◽  
Controlled Release Fertilizers

Release characteristics of four types of controlled-release fertilizers (Osmocote, Nutricote, Polyon, and Multicote) were studied during a 47-week simulated plant production cycle. The 2.4-L containers containing a low-fertility, acid-based substrate were placed in an unheated greenhouse and subjected to environmental conditions often used for production of azaleas and camellias. Leachate from containers was collected weekly and monitored for pH, electrical conductivity, and concentrations of NH4+ N, NO3–N, total P and total K. Leachate concentrations of all nutrients were relatively high during the first 10 to 20 weeks of the study, and then gradually decreased during the remaining portion of the experiment. Differences were observed among fertilizer types, with Multicote often resulting in higher concentrations of N, P, and K in leachates compared to the leachates from the other fertilizer types during the first half of the study. Concentrations of NO3– and P from all fertilizer types were often above permissible levels as cited in the federal Clean Water Act.

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