Displaying publications 141 - 160 of 473 in total

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  1. Tong SC, Siow LF, Tang TK, Lee YY
    J Sci Food Agric, 2025 Jan 30;105(2):913-925.
    PMID: 39264093 DOI: 10.1002/jsfa.13883
    BACKGROUND: Plant-based beverages have recently seen a significant increase in market demand. However, many of these products suffer from poor emulsion stability and low protein content. Gums have commonly been used to enhance emulsion stability but they do not improve the amino acid profile. This study investigated the use of multiples plant proteins to enhance both the stability and nutritional value of plant-based beverages.

    RESULT: Pea and rice bran proteins both enhanced emulsion stability. Pea protein enhanced the viscosity of the continuous phase whereas rice bran protein lowered interfacial tension. When applied synergistically, competitive adhesion occurred. Rice bran protein gradually displaced pea protein from the oil droplet surface as its concentration increased, leading to emulsion destabilization due to the displaced pea protein. The use of high-pressure homogenization further enhanced the stability of the emulsion by unfolding protein partially. However, increasing homogenization pressure (>500 Bar) and homogenization cycle (>2 cycles) led to protein aggregation due to excessive exposure of its hydrophobic core. The emulsion formed was resistant to coalescence at 4 °C for 28 days and was stable under high pH and low ionic conditions.

    CONCLUSION: The synergistic combination of plant proteins and the effective utilization of co-processing (homogenization) can enhance the functionality of the individual proteins significantly, leading to the formation of a stable emulsion. The use of plant protein mixture as a stabilizer not only improved the emulsion stability but also ensured a plant-based beverage with a complete amino acid profile for the vegan community. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

    Matched MeSH terms: Water/chemistry
  2. Musa HI, Hassan L, Shamsuddin ZH, Panchadcharam C, Zakaria Z, Aziz SA
    Environ Monit Assess, 2018 Mar 22;190(4):241.
    PMID: 29569066 DOI: 10.1007/s10661-018-6613-7
    Burkholderia pseudomallei causes melioidosis, a life-threatening infection in both humans and animals. Water is an important reservoir of the bacteria and may serve as a source of environmental contamination leading to infection. B. pseudomallei has an unusual ability to survive in water for a long period. This paper investigates physicochemical properties of water associated with the presence of B. pseudomallei in water supply in small ruminant farms in Peninsular Malaysia. Physicochemical properties of water samples taken from small ruminant farms that included temperature, pH, dissolved oxygen (DO2), optical density (OD), and chemical oxygen demand (COD) were measured after which the samples were cultured for B. pseudomallei. Multivariable logistic regression model revealed that slightly acidic water pH and higher COD level were significantly associated with the likelihood of the B. pseudomallei presence in the water.
    Matched MeSH terms: Fresh Water/chemistry; Water/chemistry
  3. Nhu TT, Schaubroeck T, Henriksson PJG, Bosma R, Sorgeloos P, Dewulf J
    Environ Pollut, 2016 Dec;219:156-165.
    PMID: 27814531 DOI: 10.1016/j.envpol.2016.10.006
    Pangasius production in Vietnam is widely known as a success story in aquaculture, the fastest growing global food system because of its tremendous expansion by volume, value and the number of international markets to which Pangasius has been exported in recent years. While certification schemes are becoming significant features of international fish trade and marketing, an increasing number of Pangasius producers have followed at least one of the certification schemes recognised by international markets to incorporate environmental and social sustainability practices in aquaculture, typically the Pangasius Aquaculture Dialogue (PAD) scheme certified by the Aquaculture Stewardship Council (ASC). An assessment of the environmental benefit of applying certification schemes on Pangasius production, however, is still needed. This article compared the environmental impact of ASC-certified versus non-ASC certified intensive Pangasius aquaculture, using a statistically supported LCA. We focused on both resource-related (water, land and total resources) and emissions-related (global warming, acidification, freshwater and marine eutrophication) categories. The ASC certification scheme was shown to be a good approach for determining adequate environmental sustainability, especially concerning emissions-related categories, in Pangasius production. However, the non-ASC certified farms, due to the large spread, the impact (e.g., water resources and freshwater eutrophication) was possibly lower for a certain farm. However, this result was not generally prominent. Further improvements in intensive Pangasius production to inspire certification schemes are proposed, e.g., making the implementation of certification schemes more affordable, well-oriented and facilitated; reducing consumed feed amounts and of the incorporated share in fishmeal, especially domestic fishmeal, etc. However, their implementation should be vetted with key stakeholders to assess their feasibility.
    Matched MeSH terms: Fresh Water/chemistry; Waste Water/chemistry
  4. Sakai N, Dayana E, Abu Bakar A, Yoneda M, Nik Sulaiman NM, Ali Mohd M
    Environ Monit Assess, 2016 Oct;188(10):592.
    PMID: 27679511
    Polychlorinated biphenyls (PCBs) were monitored in surface water collected in the Selangor River basin, Malaysia, to identify the occurrence, distribution, and dechlorination process as well as to assess the potential adverse effects to the Malaysian population. Ten PCB homologs (i.e., mono-CBs to deca-CBs) were quantitated by using gas chromatography-mass spectrometry (GC/MS). The total concentration of PCBs in the 10 sampling sites ranged from limit of detection to 7.67 ng L(-1). The higher chlorinated biphenyls (tetra-CBs to deca-CBs) were almost not detected in most of the sampling sites, whereas lower chlorinated biphenyls (mono-CBs, di-CBs, and tri-CBs) dominated more than 90 % of the 10 homologs in all the sampling sites. Therefore, the PCB load was estimated to be negligible during the sampling period because PCBs have an extremely long half-life. The PCBs, particularly higher chlorinated biphenyls, could be thoroughly dechlorinated to mono-CBs to tri-CBs by microbial decomposition in sediment or could still be accumulated in the sediment. The lower chlorinated biphenyls, however, could be resuspended or desorbed from the sediment because they have faster desorption rates and higher solubility, compared to the higher chlorinated biphenyls. The health risk for the Malaysia population by PCB intake that was estimated from the local fish consumption (7.2 ng kg(-1) bw day(-1)) and tap water consumption (1.5 × 10(-3)-3.1 × 10(-3) ng kg(-1) bw day(-1)) based on the detected PCB levels in the surface water was considered to be minimal. The hazard quotient based on the tolerable daily intake (20 ng kg(-1) bw day(-1)) was estimated at 0.36.
    Matched MeSH terms: Water/chemistry*; Drinking Water/chemistry
  5. Abd Wahib SM, Wan Ibrahim WA, Sanagi MM, Kamboh MA, Abdul Keyon AS
    J Chromatogr A, 2018 Jan 12;1532:50-57.
    PMID: 29241956 DOI: 10.1016/j.chroma.2017.11.059
    A facile dispersive-micro-solid phase extraction (D-μ-SPE) method coupled with HPLC for the analysis of selected non-steroidal anti-inflammatory drugs (NSAIDs) in water samples was developed using a newly prepared magnetic sporopollenin-cyanopropyltriethoxysilane (MS-CNPrTEOS) sorbent. Sporopollenin homogenous microparticles of Lycopodium clavatum spores possessed accessible functional groups that facilitated surface modification. Simple modification was performed by functionalization with 3-cyanopropyltriethoxysilane (CNPrTEOS) and magnetite was introduced onto the biopolymer to simplify the extraction process. MS-CNPrTEOS was identified by infrared spectrometrywhile the morphology and the magnetic property were confirmed by scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM), respectively. To maximize the extraction performance of ketoprofen, ibuprofen, diclofenac and mefenamic acid using the proposed MS-CNPrTEOS, important D-μ-SPE parameters were comprehensively optimized. The optimum extraction conditions were sorbent amount, 40 mg; extraction time, 5 min; desorption time; 5 min; sample volume, 15 mL; sample pH 2.0; and salt addition, 2.5% (w/v). The feasibility of the developed method was evaluated using spiked tap water, lake water, river water and waste water samples. Results showed that ketoprofen and ibuprofen were linear in the range of 1.0-1000 μg L-1whilst diclofenac and mefenamic acid were linear in the range 0.8-500 μg L-1. The results also showed good detection limits for the studied NSAIDs in the range of 0.21-0.51 μg L-1and good recoveries for spiked water samples in the range of 85.1-106.4%. The MS-CNPrTEOS proved a promising dispersive sorbent and applicable to facile and rapid assay of NSAIDs in water samples.
    Matched MeSH terms: Fresh Water/chemistry*; Waste Water/chemistry
  6. Ab Razak NH, Praveena SM, Aris AZ, Hashim Z
    Public Health, 2016 Feb;131:103-11.
    PMID: 26715317 DOI: 10.1016/j.puhe.2015.11.006
    Information about the quality of drinking water, together with analysis of knowledge, attitude and practice (KAP) analysis and health risk assessment (HRA) remain limited. The aims of this study were: (1) to ascertain the level of KAP regarding heavy metal contamination of drinking water in Pasir Mas; (2) to determine the concentration of heavy metals (Al, Cr, Cu, Fe, Ni, Pb, Zn and Cd) in drinking water in Pasir Mas; and (3) to estimate the health risks (non-carcinogenic and carcinogenic) caused by heavy metal exposure through drinking water using hazard quotient and lifetime cancer risk.
    Matched MeSH terms: Drinking Water/chemistry*
  7. Lin YK, Show PL, Yap YJ, Ariff AB, Mohammad Annuar MS, Lai OM, et al.
    J Biosci Bioeng, 2016 Jun;121(6):692-696.
    PMID: 26702953 DOI: 10.1016/j.jbiosc.2015.11.001
    Aqueous two-phase system (ATPS) extractive bioconversion provides a technique which integrates bioconversion and purification into a single step process. Extractive bioconversion of gamma-cyclodextrin (γ-CD) from soluble starch with cyclodextrin glycosyltransferase (CGTase, EC 2.4.1.19) enzyme derived from Bacillus cereus was evaluated using polyethylene glycol (PEG)/potassium phosphate based on ATPS. The optimum condition was attained in the ATPS constituted of 30.0% (w/w) PEG 3000 g/mol and 7.0% (w/w) potassium phosphate. A γ-CD concentration of 1.60 mg/mL with a 19% concentration ratio was recovered after 1 h bioconversion process. The γ-CD was mainly partitioned to the top phase (YT=81.88%), with CGTase partitioning in the salt-rich bottom phase (KCGTase=0.51). Repetitive batch processes of extractive bioconversion were successfully recycled three times, indicating that this is an environmental friendly and a cost saving technique for γ-CD production and purification.
    Matched MeSH terms: Water/chemistry*
  8. Masood N, Zakaria MP, Halimoon N, Aris AZ, Magam SM, Kannan N, et al.
    Mar Pollut Bull, 2016 Jan 15;102(1):160-75.
    PMID: 26616745 DOI: 10.1016/j.marpolbul.2015.11.032
    Polycyclic aromatic hydrocarbons (PAHs) and linear alkylbenzenes (LABs) were used as anthropogenic markers of organic chemical pollution of sediments in the Selangor River, Peninsular Malaysia. This study was conducted on sediment samples from the beginning of the estuary to the upstream river during dry and rainy seasons. The concentrations of ƩPAHs and ƩLABs ranged from 203 to 964 and from 23 to 113 ng g(-1) dry weight (dw), respectively. In particular, the Selangor River was found to have higher sedimentary levels of PAHs and LABs during the wet season than in the dry season, which was primarily associated with the intensity of domestic wastewater discharge and high amounts of urban runoff washing the pollutants from the surrounding area. The concentrations of the toxic contaminants were determined according to the Sediment Quality Guidelines (SQGs). The PAH levels in the Selangor River did not exceed the SQGs, for example, the effects range low (ERL) value, indicating that they cannot exert adverse biological effects.
    Matched MeSH terms: Waste Water/chemistry
  9. Zakaria MR, Hirata S, Hassan MA
    Bioresour Technol, 2015 Jan;176:142-8.
    PMID: 25460995 DOI: 10.1016/j.biortech.2014.11.027
    The present works investigate hydrothermal pretreatment of oil palm empty fruit bunch and oil palm frond fiber in a batch tube reactor system with temperature and time range from 170 to 250°C and 10 to 20min, respectively. The behavior of soluble sugars, acids, furans, and phenols dramatically changed over treatment severities as determined by HPLC. The cellulose-rich treated solids were analyzed by SEM, WAXD, and BET surface area. Enzymatic hydrolysis was performed from both pretreated slurries and washed solid, and data obtained suggested that tannic acid derived from lignin degradation was a potential cellulase inhibitor. Both partial removal of hemicellulose and migration of lignin during hydrothermal pretreatment caused structural changes on the cellulose-hemicellulose-lignin matrix, resulting in the opening and expansion of specific surface area and pore volume. The current results provided important factors that maximize conversion of cellulose to glucose from oil palm biomass by hydrothermal process.
    Matched MeSH terms: Water/chemistry*
  10. Sabiha-Hanim S, Mohd Noor MA, Rosma A
    Carbohydr Polym, 2015 Jan 22;115:533-9.
    PMID: 25439929 DOI: 10.1016/j.carbpol.2014.08.087
    Steam explosion of oil palm frond has been carried out under different temperatures between 180 and 210°C for 4 min (severity of 2.96-3.84) after impregnation of the frond chips with water or KOH solution. The effects of impregnation and steam explosion conditions of oil palm fronds on the water soluble fraction and insoluble fraction were investigated. The maximum yield of hemicelluloses in water soluble fractions recovered was 23.49% and 25.33% for water and KOH impregnation, treated with steam explosion at temperature of 210°C (severity of 3.84) with a fractionation efficiency of 77.30% and 83.32%, respectively. Under this condition, the water insoluble fractions contained celluloses at 60.83% and 64.80% for water and KOH impregnation, respectively. The steam explosion temperature of 210°C for 4 min (logR(o) 3.84) was found to be the best condition in the extraction of hemicelluloses from OPF for both types of impregnation.
    Matched MeSH terms: Water/chemistry
  11. Zailina H, Najibah H, Aiezzati AN, Praveena SM, Patimah I
    Biomed Res Int, 2014;2014:797603.
    PMID: 25530970 DOI: 10.1155/2014/797603
    A cross-sectional study was carried out to determine the arsenic (As) and cadmium (Cd) concentrations in blood, urine, and drinking water as well as the health implications on 100 residents in an urban and a rural community. Results showed the blood As, urinary Cd, DNA damage, and water As and Cs were significantly (P < 0.001) higher in the rural community. Findings showed significant (P < 0.005) correlations between blood As and DNA damage with household income, years of residence, and total glasses of daily water consumption among the rural residents. The urinary NAG concentrations, years of residence, milk powder intake (glass/week), and seafood intake (per week) were significantly correlated (P < 0.005) with urinary Cd concentrations among respondents. In addition, urinary Cd level significantly influenced the urinary NAG concentrations (P < 0.001). The rural respondents experienced significantly higher lymphocyte DNA damage and blood As influenced by their years of residence and water consumption. The Cd in drinking water also resulted in the rural respondents having significantly higher urinary NAG which had a significant relationship with urinary Cd.
    Matched MeSH terms: Drinking Water/chemistry*
  12. Tisa F, Raman AA, Daud WM
    ScientificWorldJournal, 2014;2014:348974.
    PMID: 25309949 DOI: 10.1155/2014/348974
    Simulation of fluidized bed reactor (FBR) was accomplished for treating wastewater using Fenton reaction, which is an advanced oxidation process (AOP). The simulation was performed to determine characteristics of FBR performance, concentration profile of the contaminants, and various prominent hydrodynamic properties (e.g., Reynolds number, velocity, and pressure) in the reactor. Simulation was implemented for 2.8 L working volume using hydrodynamic correlations, continuous equation, and simplified kinetic information for phenols degradation as a model. The simulation shows that, by using Fe(3+) and Fe(2+) mixtures as catalyst, TOC degradation up to 45% was achieved for contaminant range of 40-90 mg/L within 60 min. The concentration profiles and hydrodynamic characteristics were also generated. A subsequent scale-up study was also conducted using similitude method. The analysis shows that up to 10 L working volume, the models developed are applicable. The study proves that, using appropriate modeling and simulation, data can be predicted for designing and operating FBR for wastewater treatment.
    Matched MeSH terms: Waste Water/chemistry*
  13. Yarmand H, Gharehkhani S, Kazi SN, Sadeghinezhad E, Safaei MR
    ScientificWorldJournal, 2014;2014:369593.
    PMID: 25254236 DOI: 10.1155/2014/369593
    Thermal characteristics of turbulent nanofluid flow in a rectangular pipe have been investigated numerically. The continuity, momentum, and energy equations were solved by means of a finite volume method (FVM). The symmetrical rectangular channel is heated at the top and bottom at a constant heat flux while the sides walls are insulated. Four different types of nanoparticles Al2O3, ZnO, CuO, and SiO2 at different volume fractions of nanofluids in the range of 1% to 5% are considered in the present investigation. In this paper, effect of different Reynolds numbers in the range of 5000 < Re < 25000 on heat transfer characteristics of nanofluids flowing through the channel is investigated. The numerical results indicate that SiO2-water has the highest Nusselt number compared to other nanofluids while it has the lowest heat transfer coefficient due to low thermal conductivity. The Nusselt number increases with the increase of the Reynolds number and the volume fraction of nanoparticles. The results of simulation show a good agreement with the existing experimental correlations.
    Matched MeSH terms: Water/chemistry*
  14. Vakili M, Rafatullah M, Ibrahim MH, Abdullah AZ, Salamatinia B, Gholami Z
    PMID: 24984835 DOI: 10.1007/978-3-319-06746-9_3
    Many industries discharge untreated wastewater into the environment. Heavy metals from many industrial processes end up as hazardous pollutants of wastewaters.Heavy metal pollution has increased in recent decades and there is a growing concern for the public health risk they may pose. To remove heavy metal ions from polluted waste streams, adsorption processes are among the most common and effective treatment methods. The adsorbents that are used to remove heavy metal ions from aqueous media have both advantages and disadvantages. Cost and effectiveness are two of the most prominent criteria for choosing adsorbents. Because cost is so important, great effort has been extended to study and find effective lower cost adsorbents.One class of adsorbents that is gaining considerable attention is agricultural wastes. Among many alternatives, palm oil biomasses have shown promise as effective adsorbents for removing heavy metals from wastewater. The palm oil industry has rapidly expanded in recent years, and a large amount of palm oil biomass is available. This biomass is a low-cost agricultural waste that exhibits, either in its raw form or after being processed, the potential for eliminating heavy metal ions from wastewater. In this article, we provide background information on oil palm biomass and describe studies that indicate its potential as an alternative adsorbent for removing heavy metal ions from wastewater. From having reviewed the cogent literature on this topic we are encouraged that low-cost oil-palm-related adsorbents have already demonstrated outstanding removal capabilities for various pollutants.Because cost is so important to those who choose to clean waste streams by using adsorbents, the use of cheap sources of unconventional adsorbents is increasingly being investigated. An adsorbent is considered to be inexpensive when it is readily available, is environmentally friendly, is cost-effective and be effectively used in economical processes. The advantages that oil palm biomass has includes the following:available and exists in abundance, appears to be effective technically, and can be integrated into existing processes. Despite these advantages, oil palm biomasses have disadvantages such as low adsorption capacity, increased COD, BOD and TOC. These disadvantages can be overcome by modifying the biomass either chemically or thermally. Such modification creates a charged surface and increases the heavy metal ion binding capacity of the adsorbent.
    Matched MeSH terms: Waste Water/chemistry*
  15. Loo JL, Khoramnia A, Lai OM, Long K, Ghazali HM
    Molecules, 2014 Jun 23;19(6):8556-70.
    PMID: 24959682 DOI: 10.3390/molecules19068556
    Mycelium-bound lipase (MBL), from a locally isolated Geotrichum candidum strain, was produced and characterized as a natural immobilized lipase. A time course study of its lipolytic activity in 1 L liquid broth revealed the maximum MBL activity at 4 h for mycelium cells harvested after 54 h. The yield and specific activity of MBL were 3.87 g/L dry weight and 508.33 U/g protein, respectively, while less than 0.2 U/mL lipase activity was detected in the culture supernatant. Prolonged incubation caused release of the bound lipase into the growth medium. The growth pattern of G. candidum, and production and properties of MBL were not affected by the scale. The stability of mycelia harboring lipase (MBL), harvested and lyophilized after 54 h, studied at 4 °C depicted a loss of 4.3% and 30% in MBL activity after 1 and 8 months, while the activity of free lipase was totally lost after 14 days of storage. The MBL from G. candidum displayed high substrate selectivity for unsaturated fatty acids containing a cis-9 double bond, even in crude form. This unique specificity of MBL could be a direct, simple and inexpensive way in the fats and oil industry for the selective hydrolysis or transesterification of cis-9 fatty acid residues in natural triacylglycerols.
    Matched MeSH terms: Water/chemistry
  16. Thangalazhy-Gopakumar S, Al-Nadheri WM, Jegarajan D, Sahu JN, Mubarak NM, Nizamuddin S
    Bioresour Technol, 2015 Feb;178:65-9.
    PMID: 25278112 DOI: 10.1016/j.biortech.2014.09.068
    In this study, pyrolysis technique was utilized for converting palm oil sludge to value added materials: bio-oil (liquid fuel) and bio-char (soil amendment). The bio-oil yield obtained was 27.4±1.7 wt.% having a heating value of 22.2±3.7 MJ/kg and a negligible ash content of 0.23±0.01 wt.%. The pH of bio-oil was in alkaline region. The bio-char yielded 49.9±0.3 wt.%, which was further investigated for sorption efficiency by adsorbing metal (Cd(2+) ions) from water. The removal efficiency of Cd(2+) was 89.4±2%, which was almost similar to the removal efficiency of a commercial activated carbon. The adsorption isotherm was well described by Langmuir model. Therefore, pyrolysis is proved as an efficient tool for palm oil sludge management, where the waste was converted into valuable products.
    Matched MeSH terms: Water/chemistry
  17. Mohd Amin MF, Heijman SG, Lopes SI, Rietveld LC
    ScientificWorldJournal, 2014;2014:162157.
    PMID: 25197693 DOI: 10.1155/2014/162157
    This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with a 1 kDa membrane. The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments. In the beginning, the theoretical L-type of the isotherm of Giles' classification was expected with an increase in the dosage of the polymer. However, in this study, the conventional type of isotherm was not observed. It was found that the adsorption of the cationic polymer on the negatively charged glass surface was necessary and influential for the removal of atrazine. Surface-to-volume ratio adsorption experiments were performed to elucidate the mechanisms and the polymer configuration. The glass surface area was determined to be a limiting parameter in the adsorption mechanism.
    Matched MeSH terms: Water/chemistry*
  18. Maail CM, Ariffin H, Hassan MA, Shah UK, Shirai Y
    Biomed Res Int, 2014;2014:465270.
    PMID: 25057489 DOI: 10.1155/2014/465270
    Oil palm frond (OPF) juice is a potential industrial fermentation substrate as it has high sugars content and the OPF are readily available daily. However, maximum sugars yield and storage stability of the OPF juice are yet to be determined. This study was conducted to determine the effect of physical pretreatment and storage duration of OPF petiole on sugars yield. Storage stability of OPF juice at different storing conditions was also investigated. It was found that OPF petiole squeezed by hydraulic pressing machine gave the highest sugars recovery at almost 40 g/kg, accounting for a recovery yield of 88%. Storage of OPF petiole up to 72 hrs prior to squeezing reduced the free sugars by 11 g/kg. Concentrated OPF juice with 95% water removal had the best storage stability at both 4 and 30°C, when it was stored for 10 days. Moreover, concentrated OPF syrup prepared by thermal processing did not give any Maillard effect on microbial growth. Based on our results, OPF juice meets all the criteria as a good fermentation substrate as it is renewable, consistently available, and easy to be obtained, it does not inhibit microbial growth and product formation, and it contains no impurities.
    Matched MeSH terms: Water/chemistry
  19. Woi PM, Bakar MA, Rosli AN, Lee VS, Ahmad MR, Zain S, et al.
    J Mol Model, 2014 May;20(5):2219.
    PMID: 24770548 DOI: 10.1007/s00894-014-2219-3
    DFT and G4 results reveal that cations display the following trends in imparting its positive charge to acrylonitrile; H⁺ > Li⁺ > Na⁺ > K⁺ for group I and Be²⁺ > Mg²⁺ > Ca²⁺ for group II. Solvation by water molecules and interaction with cation make the cyano bond more polarized and exhibits ketene-imine character. Bond order in nitrile-cation complexes has been predicted based on the s character of the covalent bond orbitals. Mulliken, CHELPG, and NPA charges are in good agreement in predicting positive charge buildup and GIAO nuclear deshileding on C1. G4 enthalpies show that Mg²⁺ is more strongly bound to acrylonitrile than to acetonitrile by 3 kcal mol⁻¹, and the proton affinity of the former is higher by 0.8 kcal mol⁻¹. G4 enthalpies of reductions support prior experimental observation that metalated conjugated nitriles show enhanced reactivity toward weak nucleophiles to afford Michael addition products.
    Matched MeSH terms: Water/chemistry
  20. Azeem B, KuShaari K, Man ZB, Basit A, Thanh TH
    J Control Release, 2014 May 10;181:11-21.
    PMID: 24593892 DOI: 10.1016/j.jconrel.2014.02.020
    With the exponential growth of the global population, the agricultural sector is bound to use ever larger quantities of fertilizers to augment the food supply, which consequently increases food production costs. Urea, when applied to crops is vulnerable to losses from volatilization and leaching. Current methods also reduce nitrogen use efficiency (NUE) by plants which limits crop yields and, moreover, contributes towards environmental pollution in terms of hazardous gaseous emissions and water eutrophication. An approach that offsets this pollution while also enhancing NUE is the use of controlled release urea (CRU) for which several methods and materials have been reported. The physical intromission of urea granules in an appropriate coating material is one such technique that produces controlled release coated urea (CRCU). The development of CRCU is a green technology that not only reduces nitrogen loss caused by volatilization and leaching, but also alters the kinetics of nitrogen release, which, in turn, provides nutrients to plants at a pace that is more compatible with their metabolic needs. This review covers the research quantum regarding the physical coating of original urea granules. Special emphasis is placed on the latest coating methods as well as release experiments and mechanisms with an integrated critical analyses followed by suggestions for future research.
    Matched MeSH terms: Water/chemistry
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