30results about How to "Enhanced relaxation properties" patented technology

The invention relates to a method for preparing gadolinium-containing nano particles, belonging to the field of biomedicines. Liver-targeting compound and amido polymer are used to prepare polymer containing a liver-targeting group, which has ion crosslinking reaction with gadolinium brine solution to prepare the gadolinium-containing nano particles. The gadolinium-containing nano particles are used for MRI magnetic resonance imaging, and can evidently increase relaxivity and improve the imaging effect.

The invention relates to a high energy density sodium-bismuth titanate based thin dielectric film as well as a preparation method and application thereof. The high energy density sodium-bismuth titanate based thin dielectric film is prepared from Bi0.5(Na0.8K0.2)0.5TiO3-xSiZrO3. The preparation method of the high energy density sodium-bismuth titanate based thin dielectric film is a sol-gel methodand comprises the following steps: preparing a precursor solution according to stoichiometric ratio, and subsequently dropwise adding the precursor solution on a cleaned Pt / Ti / SiO2 / Si substrate for rotating and coating; carrying out 150 DEG C heat treatment, 350 DEG C heat treatment and 700 DEG C heat treatment in sequence, and repeating a spin-coating and heat treatment technology until the thickness of the film reaches 500 to 600nm; in addition, a metal top electrode also can be prepared by using a sputtering technology on the thin film. Compared with the prior art, a high energy density thin film capacitor has excellent energy storage performance (energy storage density of the high energy density thin film capacitor is 25J / cm<3> and the energy storage efficiency is 79.16 percent) and good temperature stability.

The invention provides a biodegradable poly-HPMA-Gd magnetic resonance imaging (MRI) probe used for inserting enzyme sensitive polypeptide GFLG into a poly-HPMA backbone structure. The molecular weight of a prepared polymer is basically controllable, the molecular weight is high, and the dispersion coefficient (PDI) is low; and linear HPMA-DOTA-Gd is obtained through coupling with Gd(III). The probe is an efficient nanoscale MRI probe with biocompatibility, and can be used for clinical tumor diagnosis and adjuvant therapy.

The present invention disclose a specific positive magnetic nuclear resonance contrast agent and method of preparing the same, the contrast agent is applying gadopentetate dimeglumine (Gd-DTPA) coating or scion grafting to 1-100 nm hydroxylapatite [Ca [10](PO [4][6](OH)[2], short as HA) particles, to obtain composite granule smaller than 1000 nm, modified by proserum, polyethylene imine (PEI), polyethyleneglycol (PEG) to get dispersion stability colloid solution. Comparing with the present technology the positive magnetic nuclear resonance contrast agent of the invention is provided with low toxicity, high stability, good biocompatibility, high sensibility, high relaxation capability and liver, spleen specificity. The contrast agent colloid solution can be used for enhancing contrast imaging of human body or non-human body liver or spleen.

The invention provides an oxidized graphene-metallic fullerene compound. The oxidized graphene-metallic fullerene compound comprises oxidized graphene and metallic fullerene. The metallic fullerene is loaded to the surface of the oxidized graphene under pi-pi interaction. The invention further provides a method for preparing the oxidized graphene-metallic fullerene compound and application of the oxidized graphene-metallic fullerene compound as a magnetic resonance imaging contrast agent. The oxidized graphene-metallic fullerene compound, the method and the application have the advantages that the metallic fullerene is loaded on the surface of the oxidized graphene in a pi-pi interaction mode, the method is simple, complicated surface modification effects can be omitted, and the oxidized graphene-metallic fullerene compound is excellent in water solubility, stability, biocompatibility and relaxation property and is quite suitable to be used as the MRI (magnetic resonance imaging) contrast agent.

A method for preparing gadolinium sulfide nanoparticles: using protein molecules as templates, synthesizing gadolinium sulfide nanoparticles through a biomimetic synthesis method. The preparation method of the invention has the advantages of simple process, mild reaction conditions, short preparation cycle, low cost and environmental protection. The gadolinium sulfide nanoparticles obtained in the invention have good stability, aqueous solution dispersibility and high relaxation performance, and can be used as contrast agents for magnetic resonance imaging.

The invention discloses a two-dimensional metal-organic framework structure nano-sheet, a preparation method and applications thereof. The preparation method comprises the following steps: providing amixed solution containing tetraphenylporphyrin, gadolinium metal ions, an organic solvent and water, adjusting the ratio of the organic solvent to the water in the mixed solution, and carrying out asolvothermal reaction to obtain a two-dimensional metal-organic framework structure nano-sheet with uniform size distribution; and carrying out hydrogen protonation treatment on the nano-sheet to obtain the protonated nano-sheet with the two-dimensional metal-organic framework structure. According to the invention, the obtained two-dimensional metal-organic framework structure nano-sheet can be used for magnetic resonance imaging analysis or photodynamic therapy of tumors; and the nano-sheet with uniform size distribution is obtained by adjusting the proportion of the mixed solution and carrying out solvothermal treatment, and the ultraviolet and visible absorption intensity and the ultraviolet and visible absorption intensity range of the nano-sheet are improved through hydrogen protonation treatment, so that the nano-sheet generates sensitive magnetic resonance imaging and photodynamic treatment effects on tumors.

The invention discloses a compound for preparing a ceramic material, a preparation method of the compound and a ceramic capacitor, belonging to the technical field of dielectric energy storage ceramicmaterials. The general chemical formula of the material is (1-x-y)Bi<0.5>Na<0.5>TiO<3>-ySr<0.7>Bi<0.2>TiO<3>-xBi (Mg<2 / 3>Nb<1 / 3>)O<3>, wherein x is larger than or equal to 0.0 and smaller than or equal to 0.1, and y is larger than or equal to 0.1 and smaller than or equal to 0.45. The ceramic capacitor and a multi-layer ceramic capacitor are respectively prepared by a traditional solid-phase reaction method and a tape casting method through material drying, burdening, ball milling, drying, presintering, secondary ball milling, secondary drying, granulation, molding, sintering, polishing and gold electrode coating. The preparation method is simple in preparation process, low in cost, free of pollution and high in adaptability. The ceramic material is high in energy storage density and energy storage efficiency, and the processed MLCC multilayer capacitor has extremely high charge-discharge density and short charge-discharge time.

The invention discloses a batch preparation method of a suspended nanowire manipulator. The method comprises the following steps: preparing a nanowire array growing on the edge of a slope step definedby photoetching based on an IPSLS growth mode, then, spin-coating a layer of oxygen resin colloid on the substrate on which the silicon nanowires grow; carrying out photoetching pattern operation, removing an amorphous silicon dielectric layer on the surface of the substrate by wet etching, suspending an epoxy resin colloid thin film adhered to a nanowire array on the surface of a solution, fullyreplacing the epoxy resin colloid thin film with ethanol, and carrying out a drying technology to prepare the self-assembled suspended nanowire manipulator array. According to the invention, the nanowire array is transferred to the photoetched self-supporting substrate by using a transfer technology and a critical point drying technology; the influence of solution surface tension is eliminated, the original appearance of the nanowire manipulator is kept, finally, the operable suspended nanowire manipulator array is obtained, and the method can be widely applied to various fields of nano robots, biomedical cell detection, biosensors and the like.

The invention provides tumor targeting MRI contrast agent and a preparation method thereof. The contrast agent is characterized by comprising a micromolecule gadolinium chelate part and a targeting carrier part, wherein the micromolecule gadolinium chelate part and the targeting carrier part are coupled through a covalent bond, the micromolecule gadolinium chelate part is Gd-DO3A, and the targeting carrier part contains EBP molecules. The contrast agent is good in relaxation enhancement ability, can be combined with EGFR of tumor cells in a targeting mode, has a strong targeting radiography effect and has strong practicability. Furthermore, the imaging time of the contrast agent in a body is prolonged, and the adding amount of the contrast agent is reduced.

The invention relates to conjugates that consist of macrocyclic metal complexes with biomolecules and their production. The conjugates are suitable as contrast media in NMR diagnosis and radiodiagnosis as well as as agents for radiotherapy. High relaxivity is achieved by a special liganding of macrocyclic compounds, and a fine-tuning of the relaxivity is made possible.

The invention discloses a fluorine-doped iron oxide nanoparticle contrast agent and a preparation method thereof, wherein the nanoparticles form a magnetic aggregate with a cubic structure, and the magnetic aggregate is prepared by reacting an iron precursor such as carbonyl iron or ferric oleate with sodium fluoride in the presence of oleic acid and octadecene. Compared with a traditional spherical iron oxide nanoparticle contrast agent, the contrast agent has larger effective radius and local magnetic field non-uniformity, the transverse relaxation rate r2 is obviously higher than that of conventional spherical nanoparticles and T2 magnetic resonance imaging performance is very high, so that the more accurate and reliable basis can be provided for clinical research and disease diagnosis of magnetic resonance imaging.

The invention discloses an MRI contrast agent, which comprises gadolinium oxide nanoparticles and mesoporous carbon nanoparticles. The gadolinium oxide nanoparticles are loaded in the pores of the mesoporous carbon nanoparticles. and sexual substances. The invention also discloses the preparation method and application of the MRI contrast agent. Compared with the prior art, the preparation method of the MRI contrast agent of the present invention is simple, has high relaxation rate, better hydrophilicity and biocompatibility, and has longer blood circulation time and excellent tumor targeting performance.

The invention relates to the field of electronic ceramic materials, in particular to a lead-free piezoelectric ceramic material for ventilators and a preparation method thereof, which is represented by the following chemical formula: x(Bi a Na 1‑a )TiO 3 ‑yLiNbO 3 ‑(1‑x‑y)(Bi b K 1‑b )HfO 3 ‑αLa 2 O 3 ‑βLiBiO 2 , x is 0.55-0.70, y is 0.10-0.25, a is 0.45-0.75, b is 0.45-0.75, α is 0.15-0.3%, β is 0.01-0.1%, the density of the piezoelectric ceramic material prepared by the present invention is High, piezoelectric performance is better than most lead-free piezoelectric ceramic materials, has broad application prospects, can be used to make piezoelectric valves for ventilator use.

The invention discloses a biodegradable core-crosslinked gadolinium complex-containing polymer, a preparation method and application thereof. The invention also discloses a biodegradable linear HPMA copolymer, a preparation method and application thereof. The biodegradable gadolinium complex-containing polymer of the invention has a high relaxation rate, has excellent effect as a magnetic resonance imaging contrast agent, is degradable, nontoxic, has good biocompatibility, and has good clinical application prospects.

The invention provides a tumor-targeted MRI contrast agent and a preparation method thereof, characterized in that: the contrast agent includes a small-molecule gadolinium chelate part and a targeting carrier part, a small-molecule gadolinium chelate part and a target Coupling to the carrier part through a covalent bond; wherein, the small molecule gadolinium chelate part is Gd-DO3A; the targeting carrier part includes EBP molecules. The contrast agent of the present invention has good relaxation enhancement ability, and can be targetedly combined with EGFR of tumor cells, not only has a strong targeted contrast effect, but also prolongs the imaging time of the contrast agent in the body, thereby reducing the contrast agent Adding dosage has strong practicality.

The invention provides barium titanate-based relaxor ferroelectric ceramic powder, ceramic and a preparation method and application thereof, the chemical general formula of the ceramic powder is (1-z) (Ba1-xCax) (Ti1-ySny) O3-zBi (Zn2 / 3 (Nb0.85Ta0.15) 1 / 3) O3, 0 < = x < = 0.05, 0 < = y < = 0.09, and 0.1 < = z < = 0.15. The ceramic powder is obtained by adopting a traditional solid-phase ceramic preparation technology and industrial raw materials, the sintering temperature of the ceramic can be reduced to 1150 DEG C, the discharging speed t0.9 of the material is 24 ns, the charging and discharging speed is extremely high, and the ceramic powder belongs to a novel lead-free energy storage ceramic capacitor material. The barium titanate-based relaxor ferroelectric ceramic has ultra-fast charging and discharging capacity and high power density, and has wide application prospects in the fields of pulse power equipment, high-power capacitors, directional energy weapons and the like.

The invention provides a lead-free ceramic material with high energy storage and charge-discharge performance and a preparation method thereof, the chemical formula of the ceramic material is (1-x) (Na0.5Bi0.5) 0.7 Sr0.3TiO3-xSr (Ti0.85Zr0.15) O3, and x is more than or equal to 0.10 and less than or equal to 0.40. The preparation method comprises the following steps: (1) uniformly mixing SrCO3, Na2CO3, TiO2, ZrO2 and Bi2O3 to obtain raw material powder, briquetting, presintering, crushing and sieving to obtain presintered powder; (2) carrying out ball milling on the presintered powder to obtain raw material powder; and (3) tabletting and molding the raw material powder, and sintering into porcelain to obtain the lead-free high-energy-storage and charge-discharge-performance ceramic material. The ceramic material has high energy storage performance and excellent charging and discharging performance, is a promising high-performance dielectric candidate material, and has the characteristics of environmental friendliness, high practicability and the like.

The invention relates to a micron-sized protease-sensitive near-infrared fluorescent light and magnetism dual-response micro-capsule. The micro-capsule is divided into an outer layer, a middle layer and an inner layer which are compactly combined; the outer layer comprises polymer molecules provided with electronegative functional groups and coated on the middle layer; the middle layer is a capsule wall of the micro-capsule, which is formed by wrapping and hybridizing a protease-sensitive positive ion peptide chain and magnetic nanoparticles; near-infrared fluorescent molecules and fluorescent quenching molecules are enveloped in the capsule wall; the inner layer is a capsule cavity of the micro-capsule; and the capsule cavity comprises one or a plurality of cavities which are separated by protease-sensitive positive ion peptide chain molecules. In tissues without specific proteases, real-time development and track of the micro-capsule can be finished through MRI (Magnetic Resonance Imaging) development enhancement; when reaching to tissues with specific proteases, the micro-capsule disintegrates and sends near-infrared fluorescent light, and meanwhile, MRI development is weakened; and therefore, the function of double targeted development of the micro-capsule is realized.

The invention discloses a batch preparation method of a suspended nanowire manipulator. The method comprises the following steps: preparing a nanowire array growing on the edge of a slope step definedby photoetching based on an IPSLS growth mode, then, spin-coating a layer of oxygen resin colloid on the substrate on which the silicon nanowires grow; carrying out photoetching pattern operation, removing an amorphous silicon dielectric layer on the surface of the substrate by wet etching, suspending an epoxy resin colloid thin film adhered to a nanowire array on the surface of a solution, fullyreplacing the epoxy resin colloid thin film with ethanol, and carrying out a drying technology to prepare the self-assembled suspended nanowire manipulator array. According to the invention, the nanowire array is transferred to the photoetched self-supporting substrate by using a transfer technology and a critical point drying technology; the influence of solution surface tension is eliminated, the original appearance of the nanowire manipulator is kept, finally, the operable suspended nanowire manipulator array is obtained, and the method can be widely applied to various fields of nano robots, biomedical cell detection, biosensors and the like.

The present invention disclose a specific positive magnetic nuclear resonance contrast agent and method of preparing the same, the contrast agent is applying gadopentetate dimeglumine (Gd-DTPA) coating or scion grafting to 1-100 nm hydroxylapatite [Ca [10](PO [4][6](OH)[2], short as HA) particles, to obtain composite granule smaller than 1000 nm, modified by proserum, polyethylene imine (PEI), polyethyleneglycol (PEG) to get dispersion stability colloid solution. Comparing with the present technology the positive magnetic nuclear resonance contrast agent of the invention is provided with low toxicity, high stability, good biocompatibility, high sensibility, high relaxation capability and liver, spleen specificity. The contrast agent colloid solution can be used for enhancing contrast imaging of human body or non-human body liver or spleen.

The invention relates to the field of electronic ceramic materials, and in particular, relates to a lead-free piezoelectric ceramic material for a breathing machine and a preparation method of the lead-free piezoelectric ceramic material, wherein the lead-free piezoelectric ceramic material is represented by the following chemical formula: x(Bi[a]Na[1-a])TiO[3]-yLiNbO[3]-(1-x-y)(Bi[b]K[1-b])HfO[3]-alphaLa[2]O[3]-betaLiBiO[2], x is 0.55-0.70, y is 0.10-0.25, a is 0.45-0.75, b is 0.45-0.75, alpha is 0.15-0.3%, and beta is 0.01-0.1%. The prepared piezoelectric ceramic material is high in density, the piezoelectric property of the piezoelectric ceramic material is superior to that of most of lead-free piezoelectric ceramic materials, and the piezoelectric ceramic material has wide application prospects and can be used for manufacturing piezoelectric valves for breathing machines.

The invention discloses a high-d33 lead-free strontium calcium niobate sodium tungsten bronze piezo-ferroelectric ceramic material and a preparation method thereof. The general formula of the ceramic material is Sr1.85Ca0.15NaNb5O15+x wt.%M, wherein M is Bi2O3, CuO or Li2CO3, and x is 0.1-0.25. The Bi, Cu and Li are doped to modify Sr1.85Ca0.15NaNb5O15, thereby greatly enhancing the d33 of the Sr1.85Ca0.15NaNb5O15-system dielectric ceramic. The lead-free strontium calcium niobate sodium tungsten bronze piezo-ferroelectric ceramic material has lower dielectric loss, higher maximum dielectric constant and obviously higher relaxation property, i.e., the ceramic material has higher dielectric constant within a wider temperature range. Besides, the ceramic material has favorable ferroelectric properties. The doping modification is adopted to lower the coercive field, so that the high-temperature air is polarized, thereby greatly enhancing the d33 of the ceramic material and futher displaying the piezoelectric properties of the ceramic material. The preparation method of the ceramic material is simple, and has the advantages of high repetitiveness and high yield.

The invention discloses a lead-free thin film with high energy storage density and wide working temperature, a capacitor and a preparation method thereof, the lead-free thin film with high energy storage density and wide working temperature comprises an Nb: SrTiO3 substrate and a thin film, and the thin film is arranged on the surface of the Nb: SrTiO3 substrate; the thin film is a BaHf < x > Ti < 1-x > O < 3 > thin film, wherein x is larger than or equal to 0.05 and smaller than or equal to 0.32. The preparation method comprises the following steps: preparing the BaHf < x > Ti < 1-x > O3 thin film on the surface of the Nb: SrTiO3 substrate by utilizing a ceramic target material of the BaHf < x > Ti < 1-x > O3 thin film in a magnetron sputtering manner, and then annealing to obtain the lead-free thin film with high energy storage density and wide working temperature. The lead-free film with high energy storage density and wide working temperature has the characteristics of high energy storage density and wide temperature range.

The invention provides a biodegradable poly-HPMA-Gd magnetic resonance imaging probe, which inserts the enzyme-sensitive polypeptide GFLG into the poly-HPMA main chain structure; the molecular weight of the prepared polymer is basically controllable, and the molecular weight polydispersity coefficient ( PDI) is low; and linearized HPMA-DOTA-Gd is obtained by coupling with Gd(III). The probe is a high-efficiency biocompatible nanoscale MRI magnetic resonance imaging probe, which can be used for clinical tumor diagnosis and adjuvant therapy.

The invention belongs to the technical field of nanometer materials and particularly discloses a microwave-assisted method for preparing a nano-zeolite magnetic resonance imaging contrast agent. The method comprises the following steps of: digesting an organic template agent in synthesized nano-zeolites under the assistance of microwaves, and adding into a transition metal or rare-earth metal ionsolution at certain concentration; regulating the pH value by using hydrochloric acid; putting into a microwave reactor, and performing microwave irradiation; and finally, repeatedly washing to obtain nano-zeolites exchanged by transition metals or rare-earth metals which can be taken as a magnetic resonance imaging contrast agent. The method is easy to operate, equipment is simple, and the reaction is quick. A paramagnetic, ferromagnetic or superparamagnetic magnetic resonance imaging contrast agent can be prepared; and the contrast agent is small in particle size, high in water solubility, monodispersity, stability and relaxivity, and low in toxicity. The magnetic resonance imaging contrast agent has potential clinical application value.

The invention discloses an MRI contrast agent, which is prepared from gadolinium oxide nanoparticles and mesoporous carbon nanoparticles. The gadolinium oxide nanoparticles are loaded into holes of the mesoporous carbon nanoparticles, and the surfaces of the mesoporous carbon nanoparticles are modified with biological affinity substances such as PEG. The invention further discloses a preparation method and application of the MRI contrast agent. Compared with the prior art, the MRI contrast agent is simple in preparation method, has the high relaxation rate, and good hydrophilicity and biocompatibility, and has the longer blood circulation time and excellent tumor target performance.

The invention discloses a composite for preparing ceramic materials, a preparation method thereof and a ceramic capacitor, and relates to the technical field of dielectric energy storage ceramic materials. The general chemical formula of the material is: (1‑x‑y)Bi 0.5 Na 0.5 TiO 3 -ySr 0.7 Bi 0.2 TiO 3 ‑xBi(Mg 2 / 3 Nb 1 / 3 )O 3 , where 0.0≤x≤0.1, 0.1≤y≤0.45; through the traditional solid-state reaction method and tape casting method after drying, batching, ball milling, drying, pre-calcination, secondary ball milling, secondary drying, granulation , Forming, sintering, polishing and covering gold electrodes to make ceramic capacitors and multilayer ceramic capacitors respectively. The invention has simple preparation process, low cost, no pollution and strong adaptability, the ceramic material has high energy storage density and energy storage efficiency, and the processed MLCC multilayer capacitor has extremely high charge and discharge density and short charge and discharge time.

The invention discloses a two-dimensional metal-organic framework structure nanosheet, a preparation method and application thereof. The preparation method includes: providing a mixed solution containing tetraphenylporphyrin, gadolinium metal ions, an organic solvent and water, adjusting the ratio of the organic solvent and water in the mixed solution, and performing a solvothermal reaction to obtain a binary powder with uniform scale distribution. Two-dimensional metal-organic framework nanosheets; and hydrogen protonation treatment on the nanosheets to obtain protonated two-dimensional metal-organic framework nanosheets. The two-dimensional metal-organic framework nanosheet can be used in magnetic resonance imaging analysis or photodynamic therapy of tumors. The invention obtains nanosheets with uniform size distribution by adjusting the ratio of the mixed solution and performing solvothermal treatment, and improves the ultraviolet-visible absorption intensity and range of the nanosheets through hydrogen protonation treatment, so that the nanosheets can produce sensitive magnetic properties against tumors. Resonance imaging and photodynamic therapy effects.