摘要:
A new method for the preparation of microencapsulated essential oils is disclosed. The microcapsules containing essential oils or a formulation containing thereof may be used for various non-agricultural applications.
摘要:
An amphiphilic compound is provided capable of forming vesicles or liposomes, said amphiphilic compound having at least one headgroup containing a selectively cleavable group or moiety such as a residue of a choline or phenylalanine derivative, and at least one hydrogen-bonding group located either within said headgroup and/or in close proximity thereto. The cleavable group or moiety is cleaved under selective conditions including change of chemical, physical or biological environment and is preferably cleaved enzymatically in a biological environment such as the brain or the blood. Vesicles or liposomes made from said amphiphilic compounds are suitable for delivery of a therapeutic substance or a diagnostic agent specifically to a target organ or tissue, or for delivery of a nucleic acid for gene therapy.
摘要:
The invention provides a process for improving the antifouling properties and for increasing the selectivity of commercial composite polyamide nanofiltration (NF) and reverse osmosis (RO) membranes comprising circulating a low concentration of water soluble monomers and an initiating redox couple in an aqueous solvent, without transverse pressure over the surface of the membrane thereby effecting a free-radical graft polymerization on the surface of the membrane.
摘要:
Method for the preparation of nano- and mesosized particles consisting of a lipid layer comprising at least one amphiphile and a core of an inorganic compound and/or a metal, comprising: (i) dissolving in a common solvent at least one self-aggregating amphiphile with at least one inorganic, organometallic or metallorganic precursor of said inorganic compound or metal; and (ii) either injecting the resulting solution into an aqueous solution or drying the resulting solution and re-hydrating it, so as to form particles in which the precursor is encapsulated by the amphiphile(s) and is converted therein to said inorganic compound and/or metallic solid form.
摘要:
The invention provides a process for improving the antifouling properties and for increasing the selectivity of commercial composite polyamide nanofiltration (NF) and reverse osmosis (RO) membranes comprising circulating a low concentration of water soluble monomers and an initiating redox couple in an aqueous solvent, without transverse pressure over the surface of the membrane thereby effecting a free-radical graft polymerization on the surface of the membrane.
摘要:
The invention provides a process for producing a tubular membrane assembly comprising helically winding at least one strip of fibrous material on a mandrel to produce at least a single ply tubular support member for a semi-permeable membrane, characterized by passing the strip through a heated section of the mandrel during the helical winding thereof to flatten and smooth fibers protruding along the cross-sectional width of the strip, whereby a tube with a smooth inner bore along its entire length is formed.
摘要:
The invention provides a multistage membrane system for the recovery of solvents and solutes from chromatographic systems, including first means for directing a first fluid stream of a main eluting fraction, containing target molecules to be concentrated and solvent, to a first filtration membrane unit for concentration and recovery of the target molecules at the feed side of the first membrane; second means for directing fluid streams of other eluting fractions of the chromatographic process, containing contaminants and solvent, to a second filtration membrane unit for concentration and collection of the contaminant solutes at the feed side of the second membrane unit; and third means for directing filtered solvent coming from the permeate side of the first filtration unit to the feed side of the second filtration membrane unit, whereby the filtered solvent intermixes with the fluid stream of other eluting fractions.
摘要:
Immobilized buffered gels obtained from hydroxy group containing natural or synthetic polymers and acid or basic di- or triazine derivatives are useful and highly effective media, e.g. in form of membranes, for preparative isoelectric focusing electrophoresis for separating high molecular compounds, such as proteins or peptides, from biological mixtures.
摘要:
A composite membrane which is substantially insoluble (and preferably swells no more than 10%) in acetonitrile, ethanol, hexane, toluene, N-methylpyrrolidone, dimethylsulfoxide, dimethylformamide, dimethylacetamide, and their mixtures with each other and/or with water, comprises a substrate made from copolymers or homopolymers of ethylenically unsaturated nitriles, the substrate having been subjected to the steps of: (1) insolubilizing the polymer by crosslinking; (2) coating with a silicone layer; and (3) crosslinking the silicone layer. Prior to step (2), the substrate is preferably treated with a pore protector in absence of curing agents and catalysts. The pore protector is e.g. a hydroxy-terminated polysiloxane, particularly a silanol-terminated polysiloxane; it prevents the pores from collapsing, when the support is dried during step (3), and prevents passage of the coating material deeply into the pores, thus also preventing an undue reduction of the flux of the finished membrane.
摘要:
Composite solvent stable membranes for treating organic liquids comprise a crosslinked layer of less than 5 microns in thickness supported on a solvent stable porous membrane substrate, which layer includes at least one polymer selected from polyphenylene oxide type polymers and polysulfone type polymers, provided that the crosslinked layer includes at least one polymer derived from haloalkylated polyphenylene oxide type monomers. Such composite membranes include solvent stable membranes which swell to an extent of no more than about 10% when immersed in various organic solvents, and their mixtures with each other and/or water.