CAS Technical Institute of Physics and Chemistry | Date: 2010-06-23
The present invention relates to an electrospinning device for fabricating a membrane, in particular, to an electrospinning device for fabricating membrane by using spinnerets aligned in machine direction (MD) and transverse direction (TD) in a high-voltage DC electric field, and to method for using the same. In addition to producing a single-layer nanofiber membrane from a polymer composite, the electrospinning device according to the present invention can also conveniently produce a multilayer composite nanofiber membrane from more than one polymer composites. The electrospinning device comprises a control section, an electrospinning section and an ancillary section. The electrospinning section comprises a MD spinnerets set and a TD spinnerets set that are alternately arranged and moves above a membrane collecting device in a to-and-fro scanning manner so as to improve the evenness and strength of the obtained membrane. The high-voltage DC electric field is applied between the MD and TD spinnerets sets and a stainless steel conveyer belt for collecting the membrane. A polymer solution supplied to the MD and TD spinnerets sets is split into nanoflows under the action of the electric field, accumulated on the stainless steel conveyer belt to form a membrane and carried to a collecting roller to be collected.
CAS Technical Institute of Physics and Chemistry | Date: 2012-11-06
A method for preparing stably dispersed cellulose nanofibers comprises the following steps: 1) mixing cellulose and an organic solvent, the percentage of the cellulose being 1% to 15% in weight; 2) adding an esterification agent into the resultant mixture of step 1), the molar ratio of the esterification agent to the cellulose being from 1:0.1 to 4; and 3) physically breaking the resultant mixture of step 2) until a suspension liquid with stably dispersed cellulose nanofibers of 2-1000 nm in diameter and 10-100 m in length is obtained, an esterification reaction of hydroxyl group(s) on the surface of cellulose fibers occurring at the time of the breaking. Also disclosed are dispersed cellulose nanofibers with improved compatibility to the matrix than the untreated cellulose and an improved strength of the composite materials.
CAS Technical Institute of Physics and Chemistry | Date: 2011-11-04
Disclosed are a semiconductor photocatalyst for the photocatalytic reforming of biomass derivatives for hydrogen generation, and preparation and use thereof. The semiconductor photocatalyst has the atomic composition ratio of MN-Ax; wherein MN are IIB group elements to VIA group elements, or IIIA group elements to VA group elements, A being one element or more than two elements selected from the group consisting of cobalt, nickel, iron, copper, chromium, palladium, platinum, ruthenium, rhodium, iridium and silver; and 0.02%x1.0%. The method of in-situ preparation of the highly effective semiconductor photocatalyst and catalytically reforming biomass derivatives for hydrogen generation by driving photoreaction with visible light via quantum dots is simple, fast, highly effective, inexpensive and practical. The in situ reaction can occur in sunlight without the need of harsh conditions such as calcination.
CAS Technical Institute of Physics and Chemistry | Date: 2013-01-22
Disclosed is a molecular glass of a spirofluorene derivative having a molecular structure as follows: formula (I), wherein each of R
CAS Technical Institute of Physics and Chemistry | Date: 2012-05-25
The invention discloses a polymer micro-needle array chip, comprising a substrate and a micro-needle array standing thereon; the material for preparing the micro-needle array is a polyacrylamides polymer, with the molecular weight of 1.010