Near neutral pH values are widely thought to be optimum for uptake of phosphate. This belief is based on an outdated view of soil phosphate chemistry. The literature on uptake by plants from solution ...and from soil, and especially on desorption by soil, are all consistent with a much lower pH optimum.
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BFBNIB, DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NMLJ, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This paper describes a journey which started with the question: why do farmers reapply phosphate? This led to understanding how phosphate and other specifically sorbed ions, both cations and anions ...react with soil. Under most soil conditions, they do not precipitate to give specific compounds. Rather they are specifically adsorbed onto the surface of soil particles and then penetrate the particles via diffusion mechanisms. The pathways by which they move differ between ion species; for example nickel penetrates the lattice of iron oxides but phosphate penetrates defects between particles. Such reactions change important properties of the soil. Reaction with phosphate conveys negative charge to the reacting surface and so decreases the buffering capacity for phosphate; this makes subsequent phosphate applications more effective. Nor does the diffusive penetration continue unabated; as phosphate builds up, diffusive penetration slows and then virtually stops. These effects mean that on long-term fertilised soils, phosphate fertiliser is much more effective and annual doses (if they are needed at all) should be much smaller. I suggest that failure to appreciate this is the cause of phosphate losses from farmland and consequent pollution of water bodies.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Demand for new and novel natural compounds has intensified the development of plant-derived compounds known as bioactives that either promote health or are toxic when ingested. Enhanced release of ...these bioactives from plant cells by cell disruption and extraction through the cell wall can be optimized using enzyme preparations either alone or in mixtures. However, the biotechnological application of enzymes is not currently exploited to its maximum potential within the food industry. Here, we discuss the use of environmentally friendly enzyme-assisted extraction of bioactive compounds from plant sources, particularly for food and nutraceutical purposes. In particular, we discuss an enzyme-assisted extraction of stevioside from Stevia rebaudiana , as an example of a process of potential value to the food industry.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Photon emitters placed in an optical cavity experience an environment that changes how they are coupled to the surrounding light field. In the weak-coupling regime, the extraction of light from the ...emitter is enhanced. But more profound effects emerge when single-emitter strong coupling occurs: mixed states are produced that are part light, part matter1, 2, forming building blocks for quantum information systems and for ultralow-power switches and lasers. Such cavity quantum electrodynamics has until now been the preserve of low temperatures and complicated fabrication methods, compromising its use. Here, by scaling the cavity volume to less than 40 cubic nanometres and using host–guest chemistry to align one to ten protectively isolated methylene-blue molecules, we reach the strong-coupling regime at room temperature and in ambient conditions. Dispersion curves from more than 50 such plasmonic nanocavities display characteristic light–matter mixing, with Rabi frequencies of 300 millielectronvolts for ten methylene-blue molecules, decreasing to 90 millielectronvolts for single molecules—matching quantitative models. Statistical analysis of vibrational spectroscopy time series and dark-field scattering spectra provides evidence of single-molecule strong coupling. This dressing of molecules with light can modify photochemistry, opening up the exploration of complex natural processes such as photosynthesis and the possibility of manipulating chemical bonds.
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IJS, KISLJ, NUK, SBMB, UL, UM, UPUK
Post-transition elements, together with zinc-group metals and their alloys belong to an emerging class of materials with fascinating characteristics originating from their simultaneous metallic and ...liquid natures. These metals and alloys are characterised by having low melting points (i.e. between room temperature and 300 °C), making their liquid state accessible to practical applications in various fields of physical chemistry and synthesis. These materials can offer extraordinary capabilities in the synthesis of new materials, catalysis and can also enable novel applications including microfluidics, flexible electronics and drug delivery. However, surprisingly liquid metals have been somewhat neglected by the wider research community. In this review, we provide a comprehensive overview of the fundamentals underlying liquid metal research, including liquid metal synthesis, surface functionalisation and liquid metal enabled chemistry. Furthermore, we discuss phenomena that warrant further investigations in relevant fields and outline how liquid metals can contribute to exciting future applications.
Soil phosphate research has been hampered by the persistence of superseded ideas and language. Consequently few have recognised the two phosphate-sparing effects of previous phosphate fertilizer ...application: one caused by the decreased buffering capacity; the other caused by the eventual cessation of the diffusive movement of phosphate into the adsorbing particle. This is one cause of excessive phosphate applications and thence to contamination of water.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Developing new colors for the food industry is challenging, as colorants need to be compatible with a food flavors, safety, and nutritional value, and which ultimately have a minimal impact on the ...price of the product. In addition, food colorants should preferably be natural rather than synthetic compounds. Micro-organisms already produce industrially useful natural colorants such as carotenoids and anthocyanins. Microbial food colorants can be produced at scale at relatively low costs. This review highlights the significance of color in the food industry, why there is a need to shift to natural food colors compared to synthetic ones and how using microbial pigments as food colorants, instead of colors from other natural sources, is a preferable option. We also summarize the microbial derived food colorants currently used and discuss their classification based on their chemical structure. Finally, we discuss the challenges faced by the use and development of food grade microbial pigments and how to deal with these challenges, using advanced techniques including metabolic engineering and nanotechnology.
Functional foods are a fastest growing sector of the food industry. The development of functional foods comprising omega-3 fatty acids and probiotic bacteria, through complex coacervation process is ...an emerging area of research and product development.
We reviewed relevant literature concerning the use of complex coacervation in microencapsulation, focusing primarily on the inclusion of probiotic bacteria and omega-3 oils into a single delivery format. This review covers advantages and disadvantages of the complex coacervation process to microencapsulate bioactive ingredients, viability of probiotic bacteria and oxidative stability of omega-3 oil during the complex coacervation process, the bioaccessibility of omega-3 oil and probiotic bacteria during simulated gastrointestinal conditions and in-vivo testings.
The review describes the advantages of co-encapsulation using complex coacervation followed by spray drying. It also describes the technological hurdles that need to be resolved for further development of industrial applications of co-encapsulation of probiotic bacteria and omega-3 lipids. The co-encapsulation concept has been widely used in pharmaceutical delivery systems, but is a relatively new concept in food ingredient stabilisation and delivery. There is a commercial need of co-encapsulation of multiple bioactive ingredients within a single microcapsules, due to decreased cost and enhanced product quality. Complex coacervation has been shown to be a useful method for the co-encapsulation of multiple unstable bioactive ingredients. Although in-vitro evaluation deliver useful bioavailability information, additional in-vivo and clinical trials are needed to determine the efficacy of bioactive release, particularly for microcapsules containing multiple bioactive ingredients.
•Various aspects of protein-polysaccharide complex coacervation is discussed.•Microencapsulation of omega-3 oil and probiotic bacteria through complex coacervation is reviewed.•Bioaccessibility of omega-3 oil and probiotic bacteria is investigated.•The progress in co-encapsulation of omega- 3 oil and probiotic bacteria is summarized.•Key areas of co-encapsulation in which further research is needed are highlighted.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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•The importance of surface chemistry of graphene materials is clearly described.•We discuss molecularly engineered graphene surfaces for sensing applications.•We describe the latest ...developments of these materials for sensing technology.
Graphene is scientifically and commercially important because of its unique molecular structure which is monoatomic in thickness, rigorously two-dimensional and highly conjugated. Consequently, graphene exhibits exceptional electrical, optical, thermal and mechanical properties. Herein, we critically discuss the surface modification of graphene, the specific advantages that graphene-based materials can provide over other materials in sensor research and their related chemical and electrochemical properties. Furthermore, we describe the latest developments in the use of these materials for sensing technology, including chemical sensors and biosensors and their applications in security, environmental safety and diseases detection and diagnosis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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