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Preparation and properties of high-energy-density aluminum/boroncontaining gelled fuels
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作者 Yi Chen Kang Xue +3 位作者 Yang Liu Lun Pan Xiangwen Zhang Ji-Jun Zou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期230-242,共13页
Energetic nanofluid fuel has caught the attention of the field of aerospace liquid propellant for its high energy density(HED), but it suffers from the inevitable solid-liquid phase separation problem. To resolve this... Energetic nanofluid fuel has caught the attention of the field of aerospace liquid propellant for its high energy density(HED), but it suffers from the inevitable solid-liquid phase separation problem. To resolve this problem, herein we synthesized the high-Al-/B-containing(up to 30%(mass)) HED gelled fuels, with low-molecular-mass organic gellant Z, which show high net heat of combustion(NHOC), density, storage stability, and thixotropic properties. The characterizations indicate that the application of energetic particles to the gelled fuels obviously destroys their fibrous network structures but can provide the new particle-gellant gelation microstructures, resulting in the comparable stability between 1.0%(mass) Z/JP-10 + 30%(mass) Al or B and pure JP-10 gelled fuel. Moreover, the gelled fuels with high-content Al or B exhibit high shear-thinning property, recovery capability, and mechanical strength, which are favorable for their storage and utilization. Importantly, the prepared 1.0%(mass) Z/JP-10 + 30%(mass) B(or 1.0%(mass) Z/JP-10 + 30%(mass) Al) shows the density and NHOC 1.27 times(1.30) and 1.43 times(1.21)higher than pure JP-10, respectively. This work provides a facile and valid approach to the manufacturing of HED gelled fuels with high content of energetic particles for gel propellants. 展开更多
关键词 gelled fuels Energetic aluminum/boron Low-molecular-mass organic gellant Fuel property
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A Review of Soy-Tannin Gelling for Resins Applications
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作者 Antonio Pizzi 《Journal of Renewable Materials》 SCIE EI 2023年第1期1-25,共25页
Soy flour(SF),soy protein and soy protein isolates(SPI)have been the focus of increasing research on their application as new materials for a variety of applications,mainly for wood adhesives and other resins.Tannins ... Soy flour(SF),soy protein and soy protein isolates(SPI)have been the focus of increasing research on their application as new materials for a variety of applications,mainly for wood adhesives and other resins.Tannins too have been the focus of increasing research for similar applications.While both materials are classed as non-toxic and have achieved interesting results the majority of the numerous and rather inventive approaches have still relied on some sort of hardeners or cross-linkers to bring either of them or even their combination to achieve acceptable results.The paper after a presentation of the two materials and their characteristics concentrates on the formation of gels,gelling and even hardening in the case of soy-tannin combined resins.The chapter than finishes with details of the formation of resins giving suitable wood adhesive of acceptable performance by the covalent coreaction of soy protein and tannin without any other hardener,thus totally bio-sourced,non-toxic and environment friendly as a base of further advances to expect in future by these two materials combination. 展开更多
关键词 SOY TANNIN soy-tannin coreaction gellING HARDENING WOOD
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基于FPGA的La Gell5/3小波变换的硬件电路设计 被引量:2
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作者 侯宏录 姚恩源 《兵工自动化》 2013年第2期59-62,70,共5页
为了对冗余的图像数据进行有效的压缩,提出一种基于FPGA的快速小波变换的方案。介绍了La Gell 5/3提升小波变换的原理,设计了适用于高帧频CMOS相机的La Gell 5/3提升小波变换硬件结构,采用Verilog硬件语言在QuartusII软件平台下对设计... 为了对冗余的图像数据进行有效的压缩,提出一种基于FPGA的快速小波变换的方案。介绍了La Gell 5/3提升小波变换的原理,设计了适用于高帧频CMOS相机的La Gell 5/3提升小波变换硬件结构,采用Verilog硬件语言在QuartusII软件平台下对设计方案进行了实验,利用Matlab语言对图像进行反变换,并通过变换前与反变换后图像的比对,验证了算法的可行性。实验结果证明:该方案成功实现了基于FPGA的La Gell 5/3提升小波变换系统对给定图像的三级快速小波变换,相比较于DSP等硬件电路,更适合于高速图像实时处理的应用。 展开更多
关键词 LA gell 5 3 FPGA 提升小波变换 高帧频相机
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Gelled Ionic Liquid/PMMA Polymer Electrolyte Prepared by Radical Polymerization 被引量:1
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作者 李丽波 杨硕 +1 位作者 李捷斯 国绍文 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第4期485-490,J0002,共7页
The gel polymer electrolyte containing N-propyl, methylpyrrolidinium bis((trifiuoromethyl) sulfonyl)imide (PYR13TFSI) with better performance is prepared by radical polymerization method. The interface status be... The gel polymer electrolyte containing N-propyl, methylpyrrolidinium bis((trifiuoromethyl) sulfonyl)imide (PYR13TFSI) with better performance is prepared by radical polymerization method. The interface status between the LiFePO4 electrode and the electrolyte is characterized by a scanning electron microscope and X-ray photoelectron spectroscopy (XPS). There is a layer of membrane on the gel electrolyte and perfect shell membranes on the surface of active LiFePO4 cluster, on the other hand, N and S photoelectron signals are observed in XPS spectra after charge-discharge cycles. The results show that the ionic liquids and unpolymerized methyl methacrylate incorporate into the electrode surface and form the SEI membrane with Li ion and electrons while the gel electrolyte contacts with the electrode. The formation process of the SEI membrane needs at least three cycles, the discharge capacity increases as the SEI membrane becomes sufficiently thick, which blocks further electron transfer, and the system may approach steady state. The performance of cell with ionic liquid gel polymer electrolyte is measured at different rate. The cells retain 132 mAh/g at 0.2 C, 128 mAh/g at 0.5 C, and 120 mAh/g at 1.0 C after 30 cycles with charge-discharge efficiency of ca. 98% at every rate. 展开更多
关键词 Radical polymerization gelled ELECTROLYTE ELECTROCHEMISTRY
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High-energy-density gelled fuels with high stability and shear thinning performance 被引量:5
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作者 Yang Liu Hongzhi Zhang +3 位作者 Lun Pan Kang Xue Xiangwen Zhang Ji-Jun Zou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第3期99-109,共11页
Gelled fuels are the very promising propellants for new-generation rocket and ramjet propulsion.Here we report a new type of low-molecular mass organic gellant(Z),and prepared four kinds of stable gelled fuels based o... Gelled fuels are the very promising propellants for new-generation rocket and ramjet propulsion.Here we report a new type of low-molecular mass organic gellant(Z),and prepared four kinds of stable gelled fuels based on HD-01,HD-03,RP-3 and QC liquid fuels,with the critical gellant concentration less than 1%(mass).The characterizations show that the gellant can form 3D network structure,via hydrogen bonding,π-πstacking and van der Waals forces,to fix fuel molecules during the formation of gelled fuels.So,the gelled fuels show high stability,with the remaining gel mass of 0.25%(mass)Z/HD-01 more than 90%even at high centrifugal speed of 7500 r·min^(-1),but the rheological property test shows that all gelled fuels have obvious shear thinning property,which benefits its storage in gelled state while supply in liquid state.The gelation of liquid fuels by gellant Z can increase the volumetric net heat of combustion(for HD-01,it increases from 39.58 MJ·L^(-1) to 40.76 MJ·L^(-1) with 1%(mass)Z),and liquefied gelled fuels show the comparable ignition delay time with the pristine liquid fuels.So,the gelled fuels made by gellant Z have better stability,shear thinning and combustion performances,which have great potential for the practical application. 展开更多
关键词 High-performance fuel gelled fuel gellants Fuel properties
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Experimental research on characteristic of start-up pressure wave propagation in gelled crude oil by large-scale flow loop 被引量:1
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作者 崔秀国 艾慕阳 +2 位作者 姜保良 霍连风 张立新 《Journal of Central South University》 SCIE EI CAS 2008年第S1期467-470,共4页
In order to research start-up pressure wave propagation mechanism and determine pressure wave speed in gelled crude oil pipelines accurately,experiment of Large-scale flow loop was carried out.In the experiment,start-... In order to research start-up pressure wave propagation mechanism and determine pressure wave speed in gelled crude oil pipelines accurately,experiment of Large-scale flow loop was carried out.In the experiment,start-up pressure wave speeds under various operation conditions were measured,and effects of correlative factors on pressure wave were analyzed.The experimental and theoretical analysis shows that thermal shrinkage and structural properties of gelled crude oils are key factors influencing on start-up pressure wave propagation.The quantitative analysis for these effects can be done by using volume expansion coefficient and structural property parameter of gelled crude oil.A new calculation model of pressure wave speed was developed on the basis of Large-scale flow loop experiment and theoretical analysis. 展开更多
关键词 gelled CRUDE oil START-UP pressure wave PROPAGATION CHARACTERISTIC lager-scale FLOW LOOP
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Numerical simulation of the blocking process of gelled particles in porous media with remaining polymers 被引量:1
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作者 Feng Qihong Zhang Ge +1 位作者 Yin Xiaomei Luan Zhiyong 《Petroleum Science》 SCIE CAS CSCD 2009年第3期284-288,共5页
Gelled particles can be transferred deeply inside oil reservoirs to block water channels due to their physicochemical characteristics, including swelling, deformation, and synergetic effect (reacting with polymers),... Gelled particles can be transferred deeply inside oil reservoirs to block water channels due to their physicochemical characteristics, including swelling, deformation, and synergetic effect (reacting with polymers), and then the injection profiles are significantly modified. At present, research on gelled particles is mainly focused on laboratory studies of drive mechanisms, and rarely on mathematical models describing the blocking process of gelled particles. In this paper, the blocking process of gelled particles is divided into two sub-processes: deposition and desorption due to particle deformation. A mathematical model based on filtration theory is proposed considering the effect of characteristics of gelled particles on the blocking process. Blocking laws were simulated and researched using the mathematical model. Results of the simulation of the blocking of gelled particles are quite consistent with the experimental results, which confirms the reliability of the mathematical model developed. 展开更多
关键词 gelled particles profile control blocking process numerical simulation SWELLING synergetic effect deformation
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Preparation and Properties of Embeddable Ag/Ag Cl Gelling Reference Electrode for Rebars Corrosion Monitoring in Concrete 被引量:1
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作者 汤雁冰 王胜年 +1 位作者 陈龙 范志宏 《China Ocean Engineering》 SCIE EI CSCD 2015年第6期925-932,共8页
Reference electrodes are a key part for corrosion monitoring and measurement of rebars in concrete. A reference electrode that can be buried in concrete is fabricated by using Ag/Ag Cl electrode and methyl cellulose g... Reference electrodes are a key part for corrosion monitoring and measurement of rebars in concrete. A reference electrode that can be buried in concrete is fabricated by using Ag/Ag Cl electrode and methyl cellulose gelling electrolyte. The stability, repeatability and anti-polarization of the reference electrode are investigated; the influences of the inner electrolyte loss, exterior OH- contamination, and temperature on the potential of the reference electrode are also investigated in this paper. The results show that the reference electrode has good stability, repeatability, and antipolarization. The influences of inner electrolyte loss, exterior OH- contamination, and temperature on the potential of the reference electrode are minimal. Therefore, it can be used for corrosion monitoring and measurement of rebars in concrete. 展开更多
关键词 reference electrode methyl cellulose gelling electrolyte Ag/AgCl electrode corrosion monitoring rebarsconcrete
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Encapsulation of Almond Essential Oil by Co-Extrusion/Gelling Using Chitosan as Wall Material 被引量:1
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作者 Capablanca Lucía Ferrándiz Marcela López Ainhoa 《Journal of Encapsulation and Adsorption Sciences》 2017年第1期67-74,共8页
Encapsulation confers protection to substances as essential oils from processes like oxidation, evaporation or uncontrolled release. In this study almond oil capsules were obtained by co-extrusion/gelling technique. C... Encapsulation confers protection to substances as essential oils from processes like oxidation, evaporation or uncontrolled release. In this study almond oil capsules were obtained by co-extrusion/gelling technique. Chitosan was used as shell material and sodium triphosphate pentabasic as cross linking agent. Different encapsulation process variables were studied: cross-linker concentration, nozzles size and potential. Optical microscopy was used to determine the capsules morphology and degradability tests were performed in order to study capsules degradation over time. Results showed that nozzles size and cross linking concentration are key variables to consider in the encapsulation process. Degradability tests showed rapid weight loss. 展开更多
关键词 CHITOSAN ALMOND Oil TTP Co-Extrusion/gelling
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Measurement of Reaction Rate of Gelled Acids and Calcite with the Rotating Disk Apparatus 被引量:1
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作者 Yunhu Liao Dezheng Zhang +2 位作者 Jianfeng Peng Hao Liang Yunlei Gong 《Natural Resources》 2017年第8期559-568,共10页
An investigation has been made to study the reaction kinetics of gelled acids with calcite using a rotating disk apparatus. The rheological experiments revealed that all gelled acids behaved as non-Newtonian shear thi... An investigation has been made to study the reaction kinetics of gelled acids with calcite using a rotating disk apparatus. The rheological experiments revealed that all gelled acids behaved as non-Newtonian shear thinning fluids. With the rotating disk apparatus, the reaction kinetics parameters, activation energy, and effective diffusion coefficients were determined. It was found that the reaction of gelled acid with calcite was mass transfer limited at low polymer concentration and moving toward surface reaction limited at higher polymer concentration. And the diffusion rate marginally decreased, with increasing the polymer concentration. 展开更多
关键词 REACTION Rate Mass TRANSFER Surface REACTION gelled ACID Effective DIFFUSION COEFFICIENT
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Development and evaluation of Panax notoginseng saponins contained in an in situ pHtriggered gelling system for sustained ocular posterior segment drug delivery 被引量:2
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作者 Peng Lu Renxing Wang +10 位作者 Yue Xing Yanquan Gao Qingqing Zhang Bin Xing Ying Zhang Changxiang Yu Xinfu Cai Qiang Shang Dereje Kebebe Jiaxin Pi Zhidong Liu 《Acupuncture and Herbal Medicine》 2021年第2期107-121,共15页
Objective:This study aimed to lay the foundation for the research on Panax notoginseng saponins(PNS)in pH-sensitive in situ gel and the development and improvement of related preparations.Methods:We used Carbopol■940... Objective:This study aimed to lay the foundation for the research on Panax notoginseng saponins(PNS)in pH-sensitive in situ gel and the development and improvement of related preparations.Methods:We used Carbopol■940,a commonly used pH-sensitive polymer,and the thickener hydroxypropyl methylcellulose(HPMC E4M)as an ophthalmic gel matrix to prepare an ophthalmic in situ gel of PNS.In addition,formula optimization was performed by assessing gelling capability with the results of in vitro release studies.In vitro(corneal permeation,rheological,and stability)and in vivo(ocular irritation and preliminary pharmacokinetics in the vitreous)studies were also performed.Results:The results demonstrated that the in situ gelling systems containing PNS showed a sustained release of the drug,making it an ideal ocular delivery system for improving posterior ocular bioavailability.Conclusions:This study lays the foundation for the research of PNS contained in an in situ pH-triggered gel as well as the development and improvement of related preparations.It concurrently traditional Chinese medicine with a contemporary in situ gelling approach to provide new directions for the treatment of posterior ocular diseases such as diabetic retinopathy. 展开更多
关键词 Carbopol■940 Hydroxypropyl methylcellulose Panax notoginseng saponins pH-triggered gelling system Sustained release drug delivery
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Alumina Ceramics Fabricated by in-situ Consolidation of Pre-gelling Starch 被引量:2
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作者 朱田丽 王友法 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第3期758-766,共9页
An in-situ consolidation method was developed and optimized to successfully fabricate alumina ceramics using pre-gelling starch. Our results showed that the obtained ceramics have more homogeneous microstructure, high... An in-situ consolidation method was developed and optimized to successfully fabricate alumina ceramics using pre-gelling starch. Our results showed that the obtained ceramics have more homogeneous microstructure, higher density, higher flexural strength, and favorable biocompatibility compared to the regular one. During the process, cornstarch granules swelled and deformed but no fracture was observed. After the cornstarch granules bursted, alumina particles were suspended uniformly in the three-dimensional network structure to generate a much smoother surface. Below 0.5 wt% higher cornstarch content increased the flexural strength of prepared ceramics, while above 0.5 wt% the mechanical properties were compromised. Therefore the cornstarch content of 0.5% was the optimal concentration to achieve the highest mechanical strength of the prepared ceramics, with a measured flexural strength of 341 MPa, and a relative density of 96.01%. 展开更多
关键词 pre-gelling starch in-situ consolidation alumina-ceramic flexural strength biocompatibility
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Microencapsulation of Rosemary Essential Oil by Co-Extrusion/Gelling Using Alginate as a Wall Material 被引量:1
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作者 Celia Dolcà Marcela Ferrándiz +4 位作者 Lucia Capablanca Esther Franco Elena Mira Fernanda López David García 《Journal of Encapsulation and Adsorption Sciences》 2015年第3期121-130,共10页
An essential oil is the volatile lipophilic component extracted from plants. Microencapsulation systems protect the essential oil from degradation and evaporation, and at the same time allow a sustained release. This ... An essential oil is the volatile lipophilic component extracted from plants. Microencapsulation systems protect the essential oil from degradation and evaporation, and at the same time allow a sustained release. This work analyzed and characterized the rosemary essential oil microcapsules prepared by co-extrusion technique using alginate as wall material and calcium chloride as cross linker. Several instrumental techniques were used: optical microscopy, coulter counter, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), termogravimetric analysis (TGA), spectrophotometry, antimicrobial test and chromatography. Results show that rosemary oil has pesticidal properties, and its microencapsulation allows knowing that these properties remain inside the microcapsules. 展开更多
关键词 Sodium Alginate Rosemary Oil CO-EXTRUSION gellING FTIR DSC TGA
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Extraction and characterization of gelling pectin from the peel of Poncirus trifoliata fruit 被引量:1
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作者 Kouassi L.Koffi Beda M.Yapo V.Besson 《Agricultural Sciences》 2013年第11期614-619,共6页
In the framework of searching for new pectin sources to partially compensate for domestic and regional demands, the peel (albedo) of the “non-comestible” fruit of Poncirus trifoliata was investigated using a relativ... In the framework of searching for new pectin sources to partially compensate for domestic and regional demands, the peel (albedo) of the “non-comestible” fruit of Poncirus trifoliata was investigated using a relatively simple experimental design for optimization, in which only the variable was the extraction pH (1.0, 1.5, and 2.0) on the basis of our previous studies on diverse pectin sources. The results showed that the yield of pectin (7.4%-19.8%) was strongly influenced by the extraction pH when the other parameters, namely the solid to liquid extractant (S/L) ratio, temperature (T &degC), and time (t) were fixed to 1:25 (w/v), 75&degC, and 90 min, respectively. Likewise, the galacturonic acid content (GalA: 61.4%-79.2%), total neutral sugar content (TNS: 9.1%-22.5%), degree of branching (3.5%-13.9%), homogalacturonan (HG) to rhamnogalacturonan-I (RG-I) ratio (2.2-5.6), degree of methylesterification (DM: 54-77), viscosity average molecular weight (Mν: 57-82), and gelling capacity (GC: 124-158) were all affected by the extraction pH. The optimum pH for producing pectin with good yield, quality characteristics (GalA > 65%, DM > 60, Mν > 80 kDa), and gelling capacity (GC > 150), from the peel of P. trifoliata fruit, was found to be pH 1.5. 展开更多
关键词 Poncirus trifoliata PECTIN Block Copolymers Macromolecular Characteristics gelling Strength
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The Microstructure and Gelling Mechanism of Thermo-responsive Chitosan Hydrogel System
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作者 樊东辉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第2期109-112,共4页
Thermo-respansive chitosan hydrogel system (TRCHS) was prepared and its mierostructure was investigated by scaning electron microscope (SEM) and mercury intrusion poremaster (MIP). Based on analyzing the data, a... Thermo-respansive chitosan hydrogel system (TRCHS) was prepared and its mierostructure was investigated by scaning electron microscope (SEM) and mercury intrusion poremaster (MIP). Based on analyzing the data, a special porosity property was reported at the first time. Its gelling mechanism was studied by a group of contrast experiments. Results may provide experimental and theoretical supports for how to apply it on tissue engineering scaffold and how to influeuee or control its essential properties. 展开更多
关键词 thermo-responsive chitosan hydrogel system TRCHS MICROSTRUCTURE gelling mechanism
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Preparation of Microcapsules Containing Artificial Diet for Tropical Fishes with Spray Gelling Method
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作者 Yoshinari Taguchi Takanori Suzuki +1 位作者 Natsukaze Saito Masato Tanaka 《Journal of Encapsulation and Adsorption Sciences》 2017年第1期1-9,共9页
The microcapsules containing the artificial diet for tropical fishes were prepared with the spray gelling method in order to prevent water environmental pollution. The carboxymethyl cellulose sodium aqueous solution, ... The microcapsules containing the artificial diet for tropical fishes were prepared with the spray gelling method in order to prevent water environmental pollution. The carboxymethyl cellulose sodium aqueous solution, in which α-tocopherol droplets containing the powdery artificial diet were dispersed, was dropped or sprayed into the chitosan aqueous solution. Microcapsules were prepared by forming polyionic complex shell made from chitosan and carboxymethyl cellulose sodium. In the experiment, the concentration of carboxymethyl cellulose sodium (CMCNa) was mainly changed to investigate the effect on the diameters of microcapsules, the content and the microencapsulation efficiency. The microcapsules couldn’t be prepared with the concentration of carboxymethyl cellulose sodium less than 3.0 wt%. The microcapsules were the core-shell type. The diameters of microcapsules were increased with the concentration of CMCNa and the microencapsulation efficiency of ca. 100% could be obtained by the preparation method presented in this study. The microcapsules were found to be eaten well by tropical fishes and to prevent water environmental pollution. 展开更多
关键词 Microencapsulated Diets SPRAY gellING METHOD HETEROCOAGULATION Artificial Diet CARBOXYMETHYL Cellulose Sodium
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Gelle试验假阴性原因初步分析
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作者 张爱萍 唐琦 +3 位作者 朱晓晖 商莹莹 杨华 高志强 《听力学及言语疾病杂志》 CAS CSCD 北大核心 2015年第6期578-581,共4页
目的 分析Gelle(盖莱)试验假阴性的原因。方法 2013年8月-2014年7月间因耳聋或耳鸣就诊的60例(120耳)患者行纯音听阈(PTA)、声导抗、畸变产物耳声发射(DPOAE)测试和Gelle试验,根据Gelle试验为阴性、但纯音测听显示为感音神经性... 目的 分析Gelle(盖莱)试验假阴性的原因。方法 2013年8月-2014年7月间因耳聋或耳鸣就诊的60例(120耳)患者行纯音听阈(PTA)、声导抗、畸变产物耳声发射(DPOAE)测试和Gelle试验,根据Gelle试验为阴性、但纯音测听显示为感音神经性聋或听阈正常则初步判定为Gelle试验“假阴性”;分析Gelle试验阴性耳中假阴性耳数及可能原因。结果 60例(120耳)纯音测听显示:7耳为传导性聋,23耳为混合性聋,52耳为感音神经性聋,38耳纯音听阈正常,这4类纯音测听结果相对应的Gelle试验阴性耳分别为5、11、16、3耳,其中19耳判定为“假阴性”(3耳纯音听阈正常,16耳为感音神经性聋)。110耳同时进行了声导抗测试,鼓室图为A、B及C型者分别为102、2、6耳,这三类鼓室导抗图者Gelle试验阴性者分别为22、2、4耳(其中假阴性分别为A型12耳,As型2耳,Ad型1耳,C型2耳);113耳同时进行了DPOAE测试,56耳可引出,57耳未引出,Gelle试验阴性者DPOAE引出和未引出分别为12、17耳(其中假阴性分别为DPOAE引出10耳、未引出8耳)。结论 各种类型的听力损失患者中均存在Gelle试验阴性者,但部分受试者可能为Gelle试验假阴性。在诊断听骨链异常时,Gelle试验检查只能作为辅助检查手段,须结合病史、纯音测听、声导抗、DPOAE等检查综合判断。 展开更多
关键词 gelle试验 假阴性
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Gelling Behavior of Plant Proteins and Polysaccharides in Food Systems
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作者 Florence O. Uruakpa 《Journal of Food Science and Engineering》 2012年第5期247-256,共10页
Biological macromolecules, such as proteins and polysaccharides, are widely used in food systems because their interactions impart a desirable texture to food products. Plant proteins interact with food components via... Biological macromolecules, such as proteins and polysaccharides, are widely used in food systems because their interactions impart a desirable texture to food products. Plant proteins interact with food components via protein-protein and protein-polysaccharide associations, and the formation of a matrix, which can entrap other food components such as water, lipids and flavors. These networks provide structural integrity to food products and can serve as important functional ingredients in processed foods. Intermolecular interactions of typical polysaccharides result either in simple associations or in the form of a double or triple helix. The linear double helical segments may then interact to form a super junction and a three-dimensional gel network. The formation of these structural networks takes place during processing and involves the transformation from a liquid or viscous sol into a solid material with elastic properties. Interests in the behavior of mixed gels center on the prospects of enhanced flexibility in their mechanical and structural properties compared to those of pure gels. Findings on molecular interactions between plant proteins (e.g., soy, canola and pea proteins) and polysaccharides (e.g., guar gum, carrageenan, and pectin) allow for the modification of physical and textural characteristics of mixed biopolymers to meet desired functional property. 展开更多
关键词 Molecular interactions plant proteins and polysaccharides gelling macromolecules.
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Voids size distribution in gelled waxy crude oil under dynamic and static cooling
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作者 Girma T.Chala Shaharin A.Sulaiman 《Petroleum Research》 EI 2024年第1期109-114,共6页
Waxy crude oil is known for its high wax contents that can potentially result in gelling following sufficient cooling of the transportation line in the subsea bed at offshore fields.The gelling over the entire lines r... Waxy crude oil is known for its high wax contents that can potentially result in gelling following sufficient cooling of the transportation line in the subsea bed at offshore fields.The gelling over the entire lines requires an accurately predicted restart pressure to restart the clogged and idle system.However,the common way of predicting the restart pressure has been reported to result in over-designed and predicted piping parameters.Recent research findings evidenced the formation of voids which would reduce the restart pressure significantly.The study conducted in this paper is aimed at investigating the voids size distribution in gelled crude oil across and along transportation pipelines.Sets of experiments simulating crude oil transportation during both static and dynamic cooling were conducted.The gelled crude oil below the pour point temperature was then scanned using a Magnetic Resonance Imaging(MRI)system to detect the voids formed.The resulting voids at each scanning cross-section were quantified,and their distributions were investigated.It was observed that dynamic cooling had minimal impacts on the voids size difference along the pipeline with the difference in voids areas within 10 mm^(2) to be twice and uniform for the entire flow rates tested.However,voids size in statically cooled waxy crude oil was found to be highly distributed with a maximum of 6 voids size distribution in 10 mm2 ranges.The low-end temperature had the highest size difference while the difference was decreasing with higher end temperatures.This study shows that the voids amount in dynamically cooled waxy crude oil could also be estimated with lower numbers of cross-sectional voids areas.However,the higher cross-sectional voids detection is recommended while estimating voids in statically cooled waxy crude oil. 展开更多
关键词 gelled crude oil Voids size distribution Dynamic cooling Static cooling
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海藻酸钠改性垃圾焚烧底灰-矿渣基胶凝堵漏材料研究
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作者 窦国兰 简赫达 +3 位作者 仲晓星 秦波涛 刘根 张恬 《煤炭学报》 EI CAS CSCD 北大核心 2024年第3期1475-1487,共13页
针对传统矿用水泥基堵漏材料存在的收缩开裂、高能耗及高碳排放的问题,探索采用海藻酸钠(SA)交联金属离子,制备SA改性垃圾焚烧底灰(MSWI-BA)-粒化高炉矿渣(GBFS)基胶凝堵漏材料(SWM)。通过抗压强度和凝结时间的测试,确定了最佳水固比为... 针对传统矿用水泥基堵漏材料存在的收缩开裂、高能耗及高碳排放的问题,探索采用海藻酸钠(SA)交联金属离子,制备SA改性垃圾焚烧底灰(MSWI-BA)-粒化高炉矿渣(GBFS)基胶凝堵漏材料(SWM)。通过抗压强度和凝结时间的测试,确定了最佳水固比为0.4。通过胶凝材料在不同温度下的抗压强度、收缩率及裂缝形貌的分析,探究了SA改性对胶凝材料的耐高温性能的影响,结果表明SA改性后,胶凝材料的耐高温性得到了改善,受热后改性胶凝材料表面裂缝明显减少,收缩率较改性前最大降低了26.5%,在400℃受热后,剩余抗压强度仍高达17.25 MPa。结合微观形貌、孔结构性能和热分析实验,探究了SA改性胶凝材料的形成机理,结果表明,SA改性MSWI-BA-GBFS基胶凝堵漏材料通过SA与底物中的Ca^(2+)/Al^(3+)的配位交联与碱激发底物形成的硅铝酸盐共价网络协同作用,细化孔径,减小孔容,在受热后保持基体结构的完整性,从而改善胶凝材料的抗收缩开裂性。堵漏风模拟实验结果表明,水固比0.4的SA改性MSWI-BA-GBFS基胶凝堵漏材料的堵漏性能优于矿用水泥基材料,表现出较好的堵漏性能。SA改性MSWI-BA-GBFS基胶凝堵漏材料的研制不仅为城市垃圾焚烧底灰的资源化利用提供了有效途径,还提供了一种抗压强度高、抗收缩开裂且耐高温的可以完全替代传统矿用水泥基堵漏材料的环保防灭火材料。 展开更多
关键词 海藻酸钠 垃圾焚烧底灰 胶凝材料 堵漏风 防灭火
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