74results about How to "Increased tortuosity" patented technology

Methods of manufacturing polymeric intraluminal prostheses include annealing the polymeric material to selectively modify the crystallinity thereof. Annealing may be utilized to selectively modify various properties of the polymeric material of an intraluminal prosthesis, including: selectively increasing the modulus of the polymeric material; selectively increasing the hoop strength of the intraluminal prosthesis; selectively modifying the elution rate (increase or decrease) of a pharmacological agent subsequently disposed on or within the annealed polymeric material; selectively increasing/decreasing stress in the intraluminal prosthesis; and selectively modifying the polymeric material such that it erodes at a different rate.

The present invention is concerned with the use of transition coating and transition coating composition to control and or target the release of active pharmaceutical ingredients, and biological, chemical, neutraceutical, agricultural and nutritional materials and a method of preparing controlled release systems utilizing these components.

The invention belongs to the technical field of membranes, and in particular relates to a sulfonate functionalized metal-organic framework and graphene oxide compound modified polymer hybrid proton exchange membrane and a preparation method thereof. According to the invention, a compound(MOF-SO3H@GO) of the sulfonate functionalized metal-organic framework(MOF-SO3H) and graphene oxide(GO) is prepared first and then doped into a polymer to obtain the sulfonate functionalized metal-organic framework and graphene oxide compound particles hybridized polymer hybrid proton exchange membrane. The proton exchange membrane has excellent proton conductivity under a high dampness condition, and simultaneously improves the fuel obstructive capability of the hybrid proton exchange membrane. Therefore, the (MOF-SO3H@GO) modified polymer hybrid proton exchange membrane has more superior selectivity. The method has a simple operational process, mild preparation conditions, relatively low production cost, convenience for batch and large-scale production, good industrial production basis and wide application prospects.

The invention relates to a channel type thickener with a simple structure. The channel type thickener is characterized by comprising a thickening pool with a channel type structure, a sedimentation tank and a clean water tank which are sequentially arranged in a linear way, wherein the thickening pool, the sedimentation tank and the clean water tank are arranged underground, and a top cover is arranged at the upper parts of the thickening pool, the sedimentation tank and the clean water tank; the depth of the thickening pool is larger than the depths of the sedimentation tank and the clean water tank; the bottom of the thickening pool is provided with a discharge hole; the bottom of the sedimentation tank is provided with a mud cleaning valve; one end of the mud cleaning valve is communicated with the front end of the bottom of the sedimentation tank, and the other end of the mud cleaning valve is communicated with the lower part of the thickening pool and is led to the discharge hole; the liquid at the upper part of the tail end of the sedimentation tank is led to a drainage hole; the top cover is provided with a feeding hole at the position close to the initial end of the thickening pool. According to the channel type thickener, the thickening pool, the sedimentation tank and the clean water tank are sequentially arranged in a linear way; the channel type thickener is arranged underground, has a channel type structure, and is capable of carrying out concentration treatment on tailings and discharging and recycling the separated clear water in situ; the channel type thickener is simple in structure and space-saving, and the aims of saving electricity and water can be realized.

The invention belongs to the technical field of membranes and particularly relates to a carbon nanotube/graphene oxide nanoribbon-polymer hybrid proton exchange membrane and a preparation method thereof. The proton exchange membrane is prepared by: preparing multi-wall carbon nanotubes into carbon nanotube/graphene oxide nanoribbon composite; blending the carbon nanotube/graphene oxide nanoribbon composite with a polymer solution. The proton exchange membrane prepared herein is introduced with one-dimensional and two-dimensional composite (carbon nanotube/graphene oxide nanoribbons) and thereby has good dispersity and has proton conductivity greatly improved as compared to that of pure-polymer proton exchange membranes and multiply improved particularly in high-temperature low-humidity environment; meanwhile, the invention is low in production cost, easy for batch large-scale production and has good industrial production basis and promising application prospect.

The invention belongs to the technical field of membranes, and particularly discloses a zeolite imidazate skeleton coated carbon nanotube composite material modified polymer hybrid proton exchange membrane and a preparation method thereof. Composite particles (ZIF@CNT) of a zeolite imidazate skeleton (ZIF) fully-coated carbon nano tube (CNT) are firstly prepared and are uniformly dispersed in a polymer base body, the proton conduction rate of the prepared ZIF@CNT modified polymer hybrid proton exchange membrane, compared with a relatively pure polymer proton exchange membrane, is obviously improved, and is also higher than that of a CNT modified polymer hybrid proton exchange membrane. Besides, through strong mutual effect between imidazole and polymer in ZIF@CNT, the fuel obstructing capacity of the hybrid proton exchange membrane is further improved. Therefore, the ZIF@CNT modified polymer hybrid proton exchange membrane has higher selectivity. The method disclosed by the invention is simple in operation process, mild in operation condition, relatively low in production cost and easy for batch and large-scale production, and has a wide application prospect.

The invention relates to a preparation method and applications in supported catalysts of a carrier type titanium dioxide ultrafiltration membrane. According to the preparation method, a ceramic membrane is used as the support body, the self-growing phenomenon of titanium dioxide particles at high temperature is utilized, a titanium dioxide ultrafiltration membrane layer with high flux and tortuosity is formed on the surface of the ceramic membrane support body through the interweaving of titanium dioxide nanorods and calcining, thus the tortuosity and loose degree of the membrane layer can be effectively increased; an enough space is provided for supporting catalysts on the basis of ensuring the retention capacity of the original ceramic membrane; and the overall functionalization of the ceramic membrane is realized, namely the ceramic membrane supporting of multiple catalysts is realized and the product can be used in the fields such as photocatalysis, catalytic ozonation, catalytic hydrogen peroxide oxidation and catalytic wet oxidation.

Valve for the venting circuit of a liquid tank, said valve containing:

• • a) a chamber (3) which opens into the tank and is connected via an aperture to the venting circuit; b) a float containing a head provided with a needle and able to slide vertically inside the chamber; and c) a closure member for closing off the venting aperture and itself having an aperture that can be closed off by the needle of the float, the closure member having a flexible seal which is capable of moving substantially vertically relative to the head of the float, said head being provided with a device for limiting the movement of the seal

A soundproofing assembly includes stacked layers in the form of a first set of layers (36) having good resistance to the passage of air, and a second set of layers (24) with mass-spring function including a layer (28) having a heavy viscoelastic mass and a spring type layer (26); the first set of layers includes a layer (36) of a foam with open cells of high porosity, high tortuosity and good resistance to the passage of air, the layer (36) having, owing to its high tortuosity, excellent sonic absorption properties at medium and high frequencies. The invention is useful for soundproofing motor car passenger compartments.

The invention relates to a green process for synthesizing adipic acid from cyclohexanone, wherein a transition metal modified composite MFI titanium-silicon molecular sieve is adopted as a catalyst and catalyzes molecular oxygen to oxidize cyclohexanone at an operating temperature of 40-180 DEG C under an operating pressure of 0.1-2.0 MPa so as to prepare the adipic acid, wherein a transition metal salt is modified and then is subjected to a high-temperature calcination treatment to form a composite catalyst precursor, and then a water vapor heat treatment is performed to make the transition metal ions be subjected to an ectopic selection treatment process on the catalyst so as to obtain the composite catalyst. According to the present invention, the advantages of high adipic acid selectivity and green process are provided.

The invention belongs to the technical field of membranes, and particularly relates to a CNT@Fe3O4@C modified polymer hybrid proton exchange membrane and preparation method thereof. The method comprises the step that one-dimensional (1D) type CNT@Fe3O4@C is uniformly dispersed into a polymer matrix in an oriented mode by means of a magnetic field, and the oriented CNT@Fe3O4@C modified polymer hybrid proton exchange membrane is obtained, wherein the proton conductivity of the proton exchange membrane is obviously improved compared with a pure polymer hybrid proton exchange membrane and is higher than the proton conductivity of a non-oriented CNT@Fe3O4@C modified polymer hybrid proton exchange membrane. Meanwhile, the fuel blocking capacity of the hybrid proton exchange membrane is further improved through orientation arrangement of CNT@Fe3O4@C. Accordingly, the oriented CNT@Fe3O4@C modified polymer hybrid proton exchange membrane has more excellent selectivity. The method is simple in operation process, mild in preparation condition, low in production cost and prone to batched and large-scale production and has a wide application prospect.

The invention discloses a spiral hole dual-porosity sound absorbing device and application thereof. The device is realized by forming a spiral hole in a substrate of a porous material, and the sinuosity of wound waves entering the porous material is greatly improved by a spiral channel. The sound waves first enter the spiral hole at a low frequency band and then enter micro pores of the porous material via the spiral hole. By utilizing sound energy dissipation brought by strong coupling of the wound waves between the spiral hole formed in the porous material and the micro pores of the porous material, the low-frequency sound absorption property of the sound absorbing material in the invention is enhanced. Moreover, by combining the consistently good high-frequency sound absorption propertyof the porous material, the spiral hole dual-porosity sound absorbing device disclosed by the invention can reach a sound absorption peak value at an ultralow frequency under the condition that the thickness is small, and also has a certain medium-high frequency sound absorbing ability. The device disclosed by the invention is simple in structure and practical and has excellent and wide application prospects.

The present application discloses strategies to recruit and mobilize stem cells using S1P receptor selective agonists and antagonists as wells as regulators of chemokine receptors. In an in vivo ischemic model, S1P₁/S1P₃ activation with FTY720 impeded inflammatory cell infiltration and recruited endothelial progenitor cells (EPCs) with the potential to increase microvascular remodeling. S1P₃ expression on marrow-derived cells was essential for this remodeling. Concurrent systemic S1P₃ and CXCR4 antagonism mobilized hematopoietic stem cells (HSCs) with the ability to engraft and repopulate blood cells. Pre-treatment of donor HSCs with FTY720 increased homing toward SDF-1 and improved engraftment in marrow. FTY720-coated bone allografts coupled with systemic administration of VPC01091 enhanced bone allograft integration and new bone formation in bone defects. MSCs pre-treated with FTY720 exhibited increased migration toward SDF-1, a CXCR4+ ligand. The results show that S1P is a very powerful role player in pharmacological marrow-derived stem cell mobilization and recruitment.

The invention relates to a process for preparing adipic acid through cleaning catalytic oxidation of cyclohexanone, a catalyst, and a catalyst preparation method, and discloses a transition metal-modified composite MFI titanium silicon molecular sieve and a preparation method thereof, and an adipic acid preparation, wherein a mass ratio of the preferred transition metal salt to the titanium silicon molecular sieve is (0.01-0.2):1. The catalyst preparation process respectively comprises dry ball milling, high temperature calcination, hydrothermal crystallization, and other steps. According to the present invention, the catalyst prepared according to the method is the composite catalyst having the characteristic of high dispersion of the transition metal oxide on the catalyst surface; and the modified composite MFI titanium silicon molecular sieve has high catalytic oxidation activity, and can be recovered and recycled.

The invention discloses a lithium-sulfur battery, positive electrode and negative electrode materials of the lithium-sulfur battery and a preparation method thereof. The preparation method of the positive electrode and negative electrode materials of the lithium-sulfur battery comprises the following steps: (1) in a nitrogen atmosphere, heating graphene oxide to obtain reduced graphene; and (2) ina nitrogen atmosphere, respectively mixing the reduced graphene obtained in the step (1) with sulfur powder and lithium powder, then respectively carrying out heating reaction in the nitrogen atmosphere, and after the reaction is finished, respectively obtaining the lithium-sulfur battery positive electrode material and the lithium-sulfur battery negative electrode material. The prepared positiveelectrode material and negative electrode material of the lithium-sulfur battery are used for preparing the lithium-sulfur battery, the capacity of the lithium-sulfur battery reaches 400Wh/Kg, and after 160 cycles, the charging efficiency still reaches 98%.

Described herein is a multilayer microporous film or membrane that may exhibit improved properties, including improved dielectric break down and strength, compared to prior monolayer or tri-layer microporous membranes of the same thickness. The preferred multilayer microporous membrane comprises microlayers and one or more lamination barriers. Also disclosed is a battery separator or battery comprising one or more of the multilayer microporous films or membranes. The inventive battery and battery separator is preferably safer and more robust than batteries and battery separators using prior monolayer and tri-layer microporous membranes. Also, described herein is a method for making the multilayer microporous separators, membranes or films described herein.