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High‑Performance Silicon‑Rich Microparticle Anodes for Lithium‑Ion Batteries Enabled by Internal Stress Mitigation 被引量:2
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作者 Yao Gao Lei Fan +3 位作者 Rui Zhou Xiaoqiong Du Zengbao Jiao Biao Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期99-114,共16页
Si is a promising anode material for Li ion batteries because of its high specific capacity,abundant reserve,and low cost.However,its rate performance and cycling stability are poor due to the severe particle pulveriz... Si is a promising anode material for Li ion batteries because of its high specific capacity,abundant reserve,and low cost.However,its rate performance and cycling stability are poor due to the severe particle pulverization during the lithiation/delithiation process.The high stress induced by the Li concentration gradient and anisotropic deformation is the main reason for the fracture of Si particles.Here we present a new stress mitigation strategy by uniformly distributing small amounts of Sn and Sb in Si micron-sized particles,which reduces the Li concentration gradient and realizes an isotropic lithiation/delithiation process.The Si8.5Sn0.5Sb microparticles(mean particle size:8.22μm)show over 6000-fold and tenfold improvements in electronic conductivity and Li diffusivity than Si particles,respectively.The discharge capacities of the Si_(8.5)Sn_(0.5)Sb microparticle anode after 100 cycles at 1.0 and 3.0 A g^(-1)are 1.62 and 1.19 Ah g^(-1),respectively,corresponding to a retention rate of 94.2%and 99.6%,respectively,relative to the capacity of the first cycle after activation.Multicomponent microparticle anodes containing Si,Sn,Sb,Ge and Ag prepared using the same method yields an ultra-low capacity decay rate of 0.02%per cycle for 1000 cycles at 1 A g^(-1),corroborating the proposed mechanism.The stress regulation mechanism enabled by the industry-compatible fabrication methods opens up enormous opportunities for low-cost and high-energy-density Li-ion batteries. 展开更多
关键词 Silicon anodes Silicon microparticles Lithium-ion batteries Internal stress
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Magnetic core-shell microparticles for oil removing with thermal driving regeneration property 被引量:1
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作者 Shi-Hao Chen Chuan-Lin Mou +3 位作者 Wen-Long Ma Ya-Dong Li Zi-Yu Tang Hong-Bo Deng 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2531-2544,共14页
Here, we report the construction of magnetic core-shell microparticles for oil removal with thermal driving regeneration property. Water-in-oil-in water (W/O/W) emulsions from microfluidics are used as templates to pr... Here, we report the construction of magnetic core-shell microparticles for oil removal with thermal driving regeneration property. Water-in-oil-in water (W/O/W) emulsions from microfluidics are used as templates to prepare core-shell microparticles with magnetic holed poly (ethoxylated trimethylolpropane triacrylate) (PETPTA) shells each containing a thermal-sensitive poly (N-Isopropylacrylamide) (PNIPAM) core. The microparticles could adsorb oil from water due to the special structure and be collected with a magnetic field. Then, the oil-filled microparticles would be regenerated by thermal stimulus, in which the inner PNIPAM microgels work as thermal-sensitive pistons to force out the adsorbed oil. At the same time, the adsorbed oil would be recycled by distillation. Furthermore, the adsorption capacity of the microparticles for oil keeps very stable after 1st cycle. The adsorption and regeneration performances of the microparticles are greatly affected by the size of the holes on the outer PETPTA shells, which could be precisely controlled by regulating the interfacial forces in W/O/W emulsion templates. The optimized core-shell microparticles show excellent oil adsorption and thermal driving regeneration performances nearly without secondary pollution, and would be a reliable green adsorption material for kinds of oil. 展开更多
关键词 MICROFLUIDICS Core-shell microparticles Thermal driving regeneration Secondary pollution Oil adsorption
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Research into Antibacterial Effects of Polysaccharide-Based Microparticles
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作者 Enkhtaivan Erdene Odonchimeg Munkhjargal +3 位作者 Nyamkhuu Lkhagva Enkhjargal Dorjbal Baatarkhuu Oidov Ariunsanaa Byambaa 《Advances in Microbiology》 2023年第8期386-398,共13页
Background: Due to worldwide increases in the prevalence of antibiotic-resistant bacteria, it is necessary to develop an active drug delivery system that can enable therapeutics to reach their molecular targets. Maint... Background: Due to worldwide increases in the prevalence of antibiotic-resistant bacteria, it is necessary to develop an active drug delivery system that can enable therapeutics to reach their molecular targets. Maintaining the concentration of any drug in the blood at a certain level for a long time is critical in the practice of drug therapy. With the increased frequency of drug use, the blood concentration of drugs exceeds the therapeutic level, leading to toxicity or ineffectiveness. To solve these problems, in recent years, much attention has been given to developing micro/nano preparations by encapsulating biologically active compounds on polymeric carriers. Therefore, we aimed to extract pectin from sea buckthorn peel, prepare microcapsules containing antibiotics, and determine their physical and chemical properties. Methods: Wastes were separated from sea buckthorn under “Medical raw materials Dry fruit of Hippophae rhamnoides MNS 5225:2002”. Pectin was isolated from sea buckthorn waste according to the “method for determination of pectins MNS3080:1981” standard. The degree of esterification was determined according to ISO 7623:2016. Antibiotic encapsulation with coacervates and water-based emulsions was performed. Antibiotic sensitivity was determined by microdilution according to the Clinical Laboratory Standard Institute (МТ100-S27) method. The results were determined between standard strains of Staphylococcus aureus ATCC 29213 and MRSA ATCC 2758 at different dilution concentrations. Result: Pectin is a brown powder with a sour taste and no odor. There was 71.4% esterification of pectin, 8.9% yield, 1.3% free carboxyl group, 3.2% methylated carboxyl group, 4.5% total carboxyl group, 3.5% ash, and 0.1% nitrogen. A study of the antibacterial activity of pectin containing doxycycline hyclate found that the inhibition of bacterial growth was 0.8 times less than that of pure pectin. It was 1 time less than that of doxycycline alone, and 33 times smaller than that of wontaxime when compared to pure pectin. Pectin containing doxycycline hyclate inhibited MRSA growth at a concentration 6 times lower than pure pectin. This was 2 times lower than doxycycline alone, and 8 times lower than wontaxime. Conclusion: Pectin yields 1.3 after 60 minutes of separation at a sediment concentration ratio of 1:1.15 and pH = 2. Pectin itself is antibacterial against MRSA. 展开更多
关键词 PECTIN microparticleS ANTIBACTERIAL MRSA Doxycycline Hyclate
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Study of the Effect of Preoperative Dietary Intervention on Gastrointestinal Reaction of Microparticle TACE
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作者 Weifang Liu Jingyi Lin 《Journal of Clinical and Nursing Research》 2023年第6期113-117,共5页
Objective:To evaluate the effect of preoperative dietary intervention on the gastrointestinal reaction of microparticle transcatheter arterial chemoembolization(TACE).Methods:A total of 60 patients with primary liver ... Objective:To evaluate the effect of preoperative dietary intervention on the gastrointestinal reaction of microparticle transcatheter arterial chemoembolization(TACE).Methods:A total of 60 patients with primary liver cancer who were treated in our hospital from January 2018 to October 2018 were selected for this study.The random sampling method was used to divide the patients into an intervention group(30 cases)and a control group(30 cases).The control group received routine intervention,whereas the intervention group received optimized nursing intervention.The incidence of gastrointestinal reactions,the vomiting frequency,the average vomiting volume,the incidence of stomach discomfort,the quality of life,and the anxiety and depression indicators of both groups were compared.Results:The results of all indicators of the intervention group were better than those of the control group.The incidence of gastrointestinal reactions in the intervention group was 13.9%,which was lower than 43.3%of the control group.The scores of QLQ-C30 of the intervention group were higher than those of the control group;the SAS and SDS scores in the intervention group were lower than those of the control group.Conclusion:Preoperative dietary intervention can reduce the incidence of gastrointestinal reactions of microparticle TACE and improve the symptoms of gastric discomfort among patients. 展开更多
关键词 microparticle TACE Dietary intervention Gastrointestinal reactions Quality of life Perioperative period
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A Novel Facial Cream Based on Skin Penetrable Hemp Oil Microparticles
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作者 Rachel Lubart Inbar Yariv +3 位作者 Dror Fixler Ayelet Rothstein Arie Gruzman Anat Lipovsky 《Journal of Cosmetics, Dermatological Sciences and Applications》 2023年第3期165-178,共14页
Objective: Hemp seed oil is perfect for most skin types;it moisturizes skin and protects it from inflammation, oxidation, and other causes of aging. The problem is that the Hemp oil-based products do not penetrate the... Objective: Hemp seed oil is perfect for most skin types;it moisturizes skin and protects it from inflammation, oxidation, and other causes of aging. The problem is that the Hemp oil-based products do not penetrate the skin;they remain on the skin’s surface. Recently researchers have been trying to prepare nano emulsions of hemp oil to facilitate its permeation to deep skin layers. In all techniques used today, surfactants are added to the emulsification process. These surfactants may cause unwanted skin side effects. In the present study, we prepare micronized Hemp (m-Hemp) without using any surfactants in the micronization process, thus avoiding the side effects associated with surfactant addition. Methods & Results: Particles size of m-Hemp was evaluated using electron microscopy. Various sizes of m-Hemp were found, the smallest being 100 nm in diameter. The antioxidation properties of m-Hemp were measured using the Electron Spin Resonance (ESR) technique and were found to be enhanced. Skin topography and morphology following a cream containing m-Hemp treatment were visualized by Optical Profilometry and ESEM respectively. The results show a marked improvement in skin topography in all measured parameters. In addition, human keratinocytes (HaCaT) were exposed to inflammatory conditions and were then treated using Hemp. As a result, one of the key inflammatory factors (IL-2) was significantly reduced after treatment with m-Hemp (p ≤ 0.0001). The skin penetration of the cream containing m-Hemp was tested on human skin using the IMOPE (Iterative Multi-plane Optical Property Extraction) system. The results indicate that m-Hemp penetrates both the stratum corneum and the deep epidermal layers towards the dermis. Conclusion: The new cream prepared with micronized Hemp shows significant anti-inflammatory and antioxidative effects and demonstrates the entrance of m-Hemp to the skin epidermal layer. 展开更多
关键词 HEMP microparticleS ANTI-INFLAMMATORY ANTIOXIDANT Skin Penetration
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New Properties of HM16 Ether, with Submicroparticles as Self-Functional Cells Interacting through Percussion Forces, Establishing Nature of Electrical Charges, including Gravitation
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作者 Ioan Has Simona Miclaus Aurelian Has 《Journal of Modern Physics》 2020年第6期803-853,共51页
Article continues and complements our previous articles on the HM16 ether (ETH) model. Here, we describe the mechanism of occurrence of the submicroparticle (SMP). A general hypothesis, HFVI, is introduced for the mod... Article continues and complements our previous articles on the HM16 ether (ETH) model. Here, we describe the mechanism of occurrence of the submicroparticle (SMP). A general hypothesis, HFVI, is introduced for the modalities of interaction between two SMPs, based on periodic mechanical percussion forces, produced by fundamental vibrations FVs. A mechanism for describing the interaction between a SMPs and the ETH is presented. Positive and negative particles are defined by their membrane types of movement, such as +, <span style="white-space:nowrap;">&minus;</span><em>u</em>/+, <span style="white-space:nowrap;">&minus;</span><em>v</em> vibrations, and rotations at speeds +<span style="white-space:nowrap;">&Omega;</span>/<span style="white-space:nowrap;">&minus;</span><span style="white-space:nowrap;">&Omega;</span>. The process of creating a pair of SMPs is discussed. Applying HFVI to the interaction between pairs of SMPs immobile in ETH, and considering longitudinal FVL, was obtained the forces of attraction/repulsion +<em>F</em><sub><em>L</em>21</sub>/–<em>F<sub>L</sub></em><sub>21</sub>, which correspond to the completed Coulomb force<em> F<sub>CC</sub></em> including gravitation. The resultant <em>F</em><sub>RL21</sub> will form an oriented field of forces, which is a quasielectric field <em>QE</em>, equivalent to actual <em>E</em> electric field. Considering transversal FVT, was obtained the vibratory forces +, <span style="white-space:nowrap;">&minus;</span><em>F<sub>T</sub></em><sub>21</sub>, whose resultant forms an vibrating field of forces, <em>QHs</em>, a quasimagnetic special field, which may explain some of the quantum properties of SMPs. Considering a mobile SMP, two new<em> <span style="white-space:nowrap;">&gamma;</span></em> strains in ETH appear. Strains <em><span style="white-space:nowrap;">&gamma;</span><sub>L</sub></em> are created by the displacement of SMP with velocity<em> V</em>, whose force +, <span style="white-space:nowrap;">&minus;</span><em>F<sub>T</sub></em><sub>12</sub> is the support of a component of the magnetic field <em>H</em> (quasimagnetic field <em>QH</em>), giving the <em>QH<sub>L</sub></em> component. Strains <em>γ</em><sub>R</sub> are created by the rotation of SMP with speed <span style="white-space:nowrap;">&Omega;</span>, whose force +, <span style="white-space:nowrap;">&minus;</span><em>F</em><sub>R12</sub> constitutes physical support of the component <em>QH<sub>R</sub></em> of magnetic field <em>H </em>(<em>i.e. QH)</em><em></em>. The creation of a photon PH is modelled as a special ESMP containing two zones of opposed rotations, and a mechanism is presented for its movement in the ETH with speed <em>c</em> based on the HS hypothesis of screwing in ETH, with frequency <em>ν</em>. 展开更多
关键词 Nature of Electrical Charges Submicroparticle Constitution microparticle Interaction by Percussions Ether Model HM16 with Fundamental Vibrations Completed Coulomb’s Law Photon Constitution and Travel
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Microparticle Formation and Crystallization Rate of HMX with Supercritical CO_2 Antisolvent Recrystallization 被引量:10
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作者 蔡建国 周展云 邓修 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第3期258-261,共4页
Microparticle formation and crystallization rate of 1,3,5,7-tetranitro-l,3,5,7-tetraazacyclooctane (HMX) in acetone solution using supercritical carbon dioxide antisolvent (GAS) recrystallization were studied. Scannin... Microparticle formation and crystallization rate of 1,3,5,7-tetranitro-l,3,5,7-tetraazacyclooctane (HMX) in acetone solution using supercritical carbon dioxide antisolvent (GAS) recrystallization were studied. Scanning electronic microscopy, X-ray diffraction and infrared radiation were used to examine particle size, crystallinity and chemical structure. The results show that B-HMX microparticle in different average size (2-9.5um) and with narrow size distribution were obtained by controlling the expansibility, expansion speed, initial concentration and temperature during recrystallization of HMX. The formation of nuclei may be a main cause of consumption of solute when the solution is expanded rapidly enough and the equilibrium concentration is lower, in which almost monodisperse microparticle can be obtained. 展开更多
关键词 supercritical carbon dioxide microparticle recrystallization rate 1 3 5 7-tetranitro-1 3 5 7-tetraazacyclooctane
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Preparation of Thermosensitive Chitosan Formulations Containing 5-Fluorouracil/Poly-3-hydroxybutyrate Microparticles Used as Injectable Drug Delivery System 被引量:7
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作者 昝佳 朱德权 +3 位作者 谭丰苹 蒋国强 林莹 丁富新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第2期235-241,共7页
The auto-gelling and drug release properties of the thermosensitive chitosan-β-glycerophosphate formulation were investigated. According to rheological study, gelation lag time of chitosan/β-glycerophosphate (GP) ... The auto-gelling and drug release properties of the thermosensitive chitosan-β-glycerophosphate formulation were investigated. According to rheological study, gelation lag time of chitosan/β-glycerophosphate (GP) solutions varied from 2 to 60min with different deacetylation degree of chitosan, pH, gelation temperature, and the particles in the sol. The gelation properties were also found to influence the release profilles of a hydrophilic drug, 5-fluorouracil (5-FU). Morphological examination by scanning electron microphotography demonstrated that large "pores" occurred during the gel-forming process, which created hydrophilic environment and led to the rapid initial release of the drug (85% in f'LrSt 8h). Poly-3-hydroxybutyrate (PHB), a biodegradable material, was applied here as scaffold to capture 5-FU into microparticles with high encapsulation efficiency by solvent-nonsolvent method. Combination of these microparticles into the chitosan-β-GP formulation could drop the rapid initial release from 85% down to 29% in the optimized PHB content (75%, by mass). The release could sustain for about 10 months. Tiffs study provided an understanding of the potential of injectable implant using thermosensitive chitosan-β-GP formulation containing PHB based particles for the water soluble drugs that need the property of long-term delivery. 展开更多
关键词 hydrogel CHITOSAN INJECTABLES microparticle drug release
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Role of microparticles in endothelial dysfunction and arterial hypertension 被引量:14
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作者 Thomas Helbing Christoph Olivier +2 位作者 Christoph Bode Martin Moser Philipp Diehl 《World Journal of Cardiology》 CAS 2014年第11期1135-1139,共5页
Microparticles are small cell vesicles that can be released by almost all eukaryotic cells during cellular stress and cell activation. Within the last 1-2 decades it has been shown that microparticles are useful blood... Microparticles are small cell vesicles that can be released by almost all eukaryotic cells during cellular stress and cell activation. Within the last 1-2 decades it has been shown that microparticles are useful blood surrogate markers for different pathological conditions, such as vascular inflammation, coagulation and tumour diseases. Several studies have investigated the abundance of microparticles of different cellular origins in multiple cardiovascular diseases. It thereby has been shown that microparticles released by platelets, leukocytes and endothelial cells can be found in conditions of endothelial dysfunction, acute and chronic vascular inflammation and hypercoagulation. In addition to their function as surrogate markers, several studies indicate that circulating microparticles can fuse with distinct target cells, such as endothelial cells or leukocyte, and thereby deliver cellular components of their parental cells to the target cells. Hence, microparticles are a novel entity of circulating, paracrine, biological vectors which can influence the phenotype, the function and presumably even the transcriptome of their target cells.This review article aims to give a brief overview about the microparticle biology with a focus on endothelial activation and arterial hypertension. More detailed information about the role of microparticles in pathophysiology and disease can be found in already published work. 展开更多
关键词 microparticleS Arterial hypertension Endothelial dysfunction Biological vectors INFLAMMATION
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Flexible Ag Microparticle/MXene-Based Film for Energy Harvesting 被引量:4
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作者 Yunpeng Jia Yamin Pan +5 位作者 Chunfeng Wang Chuntai Liu Changyu Shen Caofeng Pan Zhanhu Guo Xianhu Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第12期235-246,共12页
Ultra-thin flexible films have attracted wide attention because of their excellent ductility and potential versatility.In particular,the energy-harvesting films(EHFs)have become a research hotspot because of the indis... Ultra-thin flexible films have attracted wide attention because of their excellent ductility and potential versatility.In particular,the energy-harvesting films(EHFs)have become a research hotspot because of the indispensability of power source in various devices.However,the design and fabrication of such films that can capture or transform di erent types of energy from environments for multiple usages remains a challenge.Herein,the multifunctional flexible EHFs with e ective electro-/photo-thermal abilities are proposed by successive spraying Ag microparticles and MXene suspension between on waterborne polyurethane films,supplemented by a hot-pressing.The optimal coherent film exhibits a high electrical conductivity(1.17×10^(4)S m^(-1)),excellent Joule heating performance(121.3℃)at 2 V,and outstanding photo-thermal performance(66.2℃ within 70 s under 100 mW cm^(-1)).In addition,the EHFs-based single-electrode triboelectric nanogenerators(TENG)give short-circuit transferred charge of 38.9 nC,open circuit voltage of 114.7 V,and short circuit current of 0.82μA.More interestingly,the output voltage of TENG can be further increased via constructing the double triboelectrification layers.The comprehensive ability for harvesting various energies of the EHFs promises their potential to satisfy the corresponding requirements. 展开更多
关键词 Energy harvesting MXene Ag microparticle Triboelectric nanogenerator
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Supercritical Antisolvent Precipitation of Microparticles of Quercetin 被引量:5
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作者 刘学武 李志义 +1 位作者 韩冰 苑塔亮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第1期128-130,共3页
Supercritical antisolvent (SAS) process is a recently developed technology to produce micro- and nano particles. This paper presents a continuous apparatus to conduct experiment of SAS process. With the apparatus, the... Supercritical antisolvent (SAS) process is a recently developed technology to produce micro- and nano particles. This paper presents a continuous apparatus to conduct experiment of SAS process. With the apparatus, the effects of pressure, temperature and flow ratio of CO2 to the solution on the shape and size of particles are studied for the quercetin-ethanol-CO2 system. Spherical quercetin microparticles with diameters ranging form 1 μm to 6μm can be obtained while ethanol is used as organic solvent. The most effective fact on the shape and size of particles is pressure, the next is temperature and the last is the flow ratio of CO2 to solution. 展开更多
关键词 supercritical antisolvent process microparticleS QUERCETIN
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Comparison of chemiluminescence enzyme immunoassay based on magnetic microparticles with traditional colorimetric ELISA for the detection of serum α-fetoprotein 被引量:5
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作者 Qian-Yun Zhang a,b,Hui Chen a,Zhen Lin a,Jin-Ming Lin a a Beijing Key Laboratory of Microanalytical Methods and Instrumentation,Department of Chemistry,Tsinghua University,Beijing 100029,China b Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第2期130-135,共6页
A chemiluminescence enzyme immunoassay based on magnetic microparticles (MmPs-CLEIA) was developed to evaluate serum a-fetoprotein (AFP) in parallel with traditional colorimetric enzyme-linked immunosorbent assay (ELI... A chemiluminescence enzyme immunoassay based on magnetic microparticles (MmPs-CLEIA) was developed to evaluate serum a-fetoprotein (AFP) in parallel with traditional colorimetric enzyme-linked immunosorbent assay (ELISA).A systematic comparison between the MmPs-CLEIA and colorimetric ELISA concluded that the MPs-CLEIA exhibited fewer dosages of immunoreagents,less total assay time,and better linearity,recovery,precision,sensitivity and validity.AFP was detected in forty human serum samples by the proposed MPs-CLEIA and ELISA,and the results were compared with commercial electrochemiluminescence immunoassay (ECLIA) kit.The correlation coefficient between MPs-CLEIA and ELISA was obtained with R 2 0.6703;however,the correlation between MPs-CLEIA and ECLIA (R 2 0.9582) was obviously better than that between colorimetric ELISA and ECLIA (R 2 0.6866). 展开更多
关键词 a-Fetoprotein Hepatocellular carcinoma Chemiluminescence enzyme immunoassay Magnetic microparticles Colorimetric enzyme-linked immunosorbent assay
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Preparation and Crystal Modification of Ibuprofen-Loaded Solid Lipid Microparticles 被引量:4
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作者 龙春霞 章莉娟 钱宇 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4期518-525,共8页
An emulsion-congealing technique is used to prepare solid lipid microparticles (SLM) containing ibuprofen with glyceryl behenate, tripalmitin and beewax as excipients. The difference of the solubility parameters bet... An emulsion-congealing technique is used to prepare solid lipid microparticles (SLM) containing ibuprofen with glyceryl behenate, tripalmitin and beewax as excipients. The difference of the solubility parameters between the excipients and ibuprofen are used to analyze their compatibility. Both the solubility parameter analysis and the experimental results show that glyceryl behenate is the best among the three excipients. The solid particles disperse well in aqueous phase when the drug loading reaches 10% (relative to lipid only). Glycerides exhibit marked polymorphism and their rapid rates of crystallization accelerate the formation of metastable crystal modification. The metastable crystal modification characterizes high drug loading capacity but less stability. Increasing the content of lipophilic drug in a lipid matrix facilitates the transformation of excipients to more stable polymorphic forms. 展开更多
关键词 solid lipid microparticles crystal modification solubility parameter drug loading capacity IBUPROFEN
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Seasonal and Spatial Variability of Microparticles in Snowpits on the Tibetan Plateau, China 被引量:3
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作者 ZHANG Yulana KANG Shichang +3 位作者 ZHANG Qianggong CONG Zhiyuan ZHANG Yongjun GAO Tanguang 《Journal of Mountain Science》 SCIE CSCD 2010年第1期15-25,共11页
The work presents microparticle concentrations in snowpits from the East Rongbuk Glacier on Mt. Qomolangma (Everest) (ER) (28.02°N, 86.96°E, 6536 m a.s.l.), the Zhadang Glacier on Mt. Nyainqentanglha (NQ) (3... The work presents microparticle concentrations in snowpits from the East Rongbuk Glacier on Mt. Qomolangma (Everest) (ER) (28.02°N, 86.96°E, 6536 m a.s.l.), the Zhadang Glacier on Mt. Nyainqentanglha (NQ) (30.47°N, 90.65°E, 5800m a.s.l.), and the Guoqu Glacier on Mt. Geladaindong (GL) (33.95°N, 91.28°E, 5823m a.s.l.) over the Tibetan Plateau (TP). Variations of microparticle and major ions (e.g. Mg2+, Ca2+) concentrations in snowpits show that the values of the microparticles and ions in the non-monsoon seasons are much higher than those in the monsoon seasons. Annual flux of microparticle deposition at ER is lower than those at NQ and GL, which could be attributed to the long distance away from the possible dust source regions as well as the elevation for ER higher than the others. Compared with other remote areas, microparticle concentrations in the southern TP are much lower than those in the northern TP, but still much higher than those in Greenland and Antarctica. The seasonal and spatial microparticle variations are clearly related to the variations of atmospheric circulation according to the air mass 5-day backward trajectory analyses of HYSPLIT Model. Resultingly, the high microparticle values in snow are mainly attributed to the westerlies and the strong dust storm outbreaks on the TP, while the monsoon circulation brings great amount of precipitation from the Indian Ocean, thus reducing in the aerosol concentrations. 展开更多
关键词 microparticle seasonal change SPATIALVARIATION snowpits Tibetan Plateau
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Synthesis and morphology of triangular pyramid-shaped puerarin microparticle with nanostructure 被引量:3
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作者 Lu, Chuan Hua Zhang, Qun Wei 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第4期484-487,共4页
A type of triangular pyramid-shaped microparticles of puerarin was synthesized by using oil-in-oil microemulsion approach which is simple and economical under the action of copper substrate.The pyramid-shaped micropar... A type of triangular pyramid-shaped microparticles of puerarin was synthesized by using oil-in-oil microemulsion approach which is simple and economical under the action of copper substrate.The pyramid-shaped microparticles would be made up of deposit of nanospheres or nanorods and have two significant characters.One is its complex surface morphology like coral reef.The other is a lot of nanopores in existence in the microparticle body.Two possible formation routes were speculated. 展开更多
关键词 Triangular pyramid-shaped puerarin microparticles SYNTHESIS NANOSPHERE Nanorod
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Synthesis of Iron-containing Carbon Microparticles from Deoiled Asphalt and Ferrocene 被引量:3
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作者 YANG Yong-zhen ZHANG Chun-yi +2 位作者 JI Wei-yun LIU Xu-guang XU Bing-she 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第B12期228-231,共4页
The deoiled asphalt as the carbon source and the ferrocene as the metal source and the catalyst precursor were chosen to synthesize iron-containing carbon microparticles through co-carbonization at the temperature of ... The deoiled asphalt as the carbon source and the ferrocene as the metal source and the catalyst precursor were chosen to synthesize iron-containing carbon microparticles through co-carbonization at the temperature of about 450℃ for 3 h. The resulting products were treated at 2 000 ℃ for 2 h. All samples were examined by high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). The results show that the iron particles in the heat-treated material are completely coated by carbon. In addition to the fully filled carbon microparticles as well as hollow carbon ones, also form carbon fibers with hollow centers. The formation mechanism of the as-prepared products was discussed briefly. 展开更多
关键词 aeronautic materials iron-containing carbon microparticles deoiled asphalt co-carbonizition high temperature heat treatment
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Increased levels of circulating platelet-derived microparticles in psoriasis:Possible implications for the associated cardiovascular risk 被引量:2
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作者 Evangelia Papadavid Konstantina Diamanti +8 位作者 Aris Spathis Maria Varoudi Ioanna Andreadou Kostas Gravanis Kostas Theodoropoulos Petros Karakitsos John Lekakis Dimitrios Rigopoulos Ignatios Ikonomidis 《World Journal of Cardiology》 CAS 2016年第11期667-675,共9页
AIM To evaluate platelet activation markers in psoriasis patients, compared to controls, and investigate their association with the inflammatory burden of psoriasis.METHODS Forty psoriatic patients without cardiovascu... AIM To evaluate platelet activation markers in psoriasis patients, compared to controls, and investigate their association with the inflammatory burden of psoriasis.METHODS Forty psoriatic patients without cardiovascular disease,and 12 healthy controls were subjected to measurement of baseline platelet CD62 P, CD63 and CD42 b expression, platelet-leukocyte complexes, i.e., platelet-monocyte complexes(PMC), platelet-neutrophil complexes(PNC) and platelet-lymphocyte complexes, and concentrations of platelet-derived microparticles(PMPs) using flow cytometry. Both larger-size(0.5-0.9 μm) and smallersize(< 0.5 μm) PMPs were determined. Serum interleukin(IL)-12 and IL-17 levels were also measured by enzyme-linked immunosorbent assay. The severity of psoriasis was evaluated by the Psoriasis Area Severity Index(PASI).RESULTS PMP concentrations were significantly higher in psoriasis patients than controls [mean±standard error of mean(SEM): 22±5/μL vs 11±6/μL; P=0.018), for both smaller-size(10±2/μL vs 4±2/μL; P=0.033) and larger-size(12±3/μL vs 6±4/μL; P=0.014) PMPs. Platelet CD62 P, CD63 and CD42 b expression and circulating PMC and PNC were similar between the two groups. Lower circulating PLC were observed in psoriasis patients compared to controls(mean±SEM: 16%±3% vs 23%±6%; P=0.047). Larger-size PMPs were related with IL-12 levels(P<0.001) and smaller-size PMPs with both IL-12 and IL-17 levels(P<0.001). Total PMPs also correlated with IL-12(P<0.001). CD63 expression was positively correlated with both IL-12 and IL-17(P<0.05). Increased PASI score was associated with increased levels of larger-size PMPs(r=0.45; P=0.011) and increased CD63 expression(r=0.47; P<0.01).CONCLUSION PMPs, known to be predictive of cardiovascular outcomes, are increased in psoriasis patients, and associated with high inflammatory disease burden. Enhanced platelet activation may be the missing link leading to cardiovascular events in psoriatic patients. 展开更多
关键词 PSORIASIS ATHEROSCLEROSIS INFLAMMATION Platelet activation Platelet-derived microparticles
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DETECTION OF PLATELET-DERIVED MICROPARTICLES USING FLOW CYTOMETRY AND ITS CLINICAL APPLICATION 被引量:2
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作者 崔巍 马文新 +1 位作者 林其燧 韩晔华 《Chinese Medical Sciences Journal》 CAS CSCD 2003年第1期26-30,共5页
Objective.To establish a flow cytometric internal standard method for counting platelet-derived microparti-cles(PMPs)and to study its clinical significance. Methods. PMPs suspension(platelet poor plasma,PPP) was extra... Objective.To establish a flow cytometric internal standard method for counting platelet-derived microparti-cles(PMPs)and to study its clinical significance. Methods. PMPs suspension(platelet poor plasma,PPP) was extracted by gradual centrifugation. According to the size of PMPs,3 μm and 0.8μm latex beads were used as internal standards for the quantitation. PMPs were counted by adjusting flow cytometric discrimination and voltage of forward scatter and side scatter. Results. In 30 healthy donors,the average concentration of resting PMPs was(1.2×105±5.7×104 )/ml and that of activated PMPs was(1.6×106±9.1×105)/ml. Compared with healthy donors,PMPs mean value was significantly higher(P< 0.001)in 18 patients with coronary artery disease,12 with acute cerebral infraction and 23 with chronic renal failure[the average PMPs concentration,( 6.1×105±2.5×105 )/ml, ( 6.8×105±3.4×105)/ml and(5.9×105±3.1×105)/ml respectively]. However,no significant difference in PMPs concentration was observed in 25 patients with acute leukemia and severe thrombocytopenia during the aplastic phase after chemotherapy [1.3×105±6.1×104)/ml,(P >0.05)] .Conclusions. PMPs is a useful indicator in monitoring platelet activation,and plays an important role in thrombotic disease. By flow cytometric internal standard method,PMPs can be counted rapidly and accurately,which may be very helpful in interlaboratory comparative studies. 展开更多
关键词 platelet microparticles platelet activation flow cytometry
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Influence of solvent mixtures on HPMCAS-celecoxib microparticles prepared by electrospraying 被引量:3
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作者 Adam Bohr Yingya Wang +1 位作者 Moritz Beck-Broichsitter Mingshi Yang 《Asian Journal of Pharmaceutical Sciences》 SCIE 2018年第6期584-591,共8页
Hypromellose acetate succinate(HPMCAS) microparticles containing the poorly-water soluble drug celecoxib(CEL) were prepared by electrospraying intended for oral drug delivery. Various solvent mixtures with different s... Hypromellose acetate succinate(HPMCAS) microparticles containing the poorly-water soluble drug celecoxib(CEL) were prepared by electrospraying intended for oral drug delivery. Various solvent mixtures with different solubility for CEL and HPMCAS were used to induce changes in the polymer structural conformation of the microparticles. The performance of the prepared microparticles was evaluated by studying the solid state from, particle size and morphology, radial drug distribution and drug release. CEL was amorphous in all electrosprayed HPMCAS microparticles. The particle size and morphology was dependent on the solubility of HPMCAS in the solvent mixture used with poorer solvents resulting in smaller microparticles with rougher appearance. The CEL distribution on the particles surface was relatively homogeneous and similar for all microparticles. Drug release from the microparticles was observed at a higher rate depending on the solubility of HPMCAS in the solvent used for electrospraying, and in all cases an at least 4-fold higher rate was observed compared with the crystalline drug. Drug precipitation from the supersaturated solution was inhibited by HPMCAS for all microparticles based on its parachute effect while crystalline CEL did not reach supersaturation. This study demonstrated that electrospraying can be used to produce microparticles with tailored properties for pharmaceutical application by adjusting solvent selection. 展开更多
关键词 CELECOXIB ELECTROSPRAYING Hypromellose acetate succinate Oral drug delivery Polymeric microparticles Solvent mixture
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Dynamics of circulating microparticles in chronic kidney disease and transplantation:Is it really reliable marker? 被引量:3
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作者 Ismail Dursun Sibel Yel Emel Unsur 《World Journal of Transplantation》 2015年第4期267-275,共9页
The deterioration of endothelial structure plays a very important role in the development of vascular diseases. It is believed that endothelial dysfunction starts in the early stage of kidney disease and is a risk fac... The deterioration of endothelial structure plays a very important role in the development of vascular diseases. It is believed that endothelial dysfunction starts in the early stage of kidney disease and is a risk factor of an unfavorable cardiovascular prognosis. Because a direct assessment of biological states in endothelial cells is not applicable, the measurement of endothelial microparticles(EMPs) detached from endothelium during activation or apoptosis is thought to be a marker of early vascular disease and endothelial dysfunction in children with chronic kidney disease(CKD). Few studies have shown increased circulating EMPs and its relationship with cardiovascular risk factors in patients with CKD.MPs contain membrane proteins and cytosolic material derived from the cell from which they originate. EMPs having CD144, CD 146, CD31+/CD41-, CD51 and CD105 may be used to evaluate the vascular endothelial cell damage and determine asymptomatic patients who might be at higher risk of developing cardiovascular disease in CKD and renal transplant. 展开更多
关键词 ENDOTHELIAL DYSFUNCTION ENDOTHELIAL microparticleS KIDNEY transplantation Chronic KIDNEY disease
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