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

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 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 relates to a high energy storage density bismuth sodium titanate-based dielectric film and its preparation method and application, consisting of Bi 0.5 (Na 0.8 K 0.2 ) 0.5 TiO 3 ‑xSrZrO 3 , the preparation method is the sol-gel method, the precursor solution is configured according to the stoichiometric ratio, and then dropped into the cleaned Pt / Ti / SiO 2 / Spin coating on Si substrate, followed by heat treatment at 150°C-350°C-700°C, repeat the above spin coating and heat treatment process until the film thickness reaches 500-600nm, and the sputtering process can also be used on the thin film to prepare the metal upper electrode . Compared with the prior art, the high energy storage density film capacitor prepared by the present invention has excellent energy storage performance, and its energy storage density is 25J / cm 3 , the energy storage efficiency is 79.16%, and the temperature stability is good.

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 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 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 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 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 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.