Preparation of natural brucite nanofibers by the dispersion method

The preparation of natural brucite nanofibers through dispersion by the wet process is described. The test results indicate that brucite fibers can be well dispersed by using sodium dioctyl sulfosuccinate （OT） as the dispersant at a dispersant/fiber mass ratio of 0.15：1, dispersing for 30 min at a water/solid mass ratio of 20：1. The prepared nanofibers were characterized with X-ray diffraction （XRD）, scanning electron microscope （SEM）, and transmission electron microscope （TEM）. It is shown that the prepared single brucite nanofiber is around 30 nm in diameter and the talus of the nonsingle brucite nanofibers is about 50-150 nm in diameter. Natural brucite mineral fibers were treated by the dispersion method to obtain nanomaterials. These fibers have significant advantages over artificial nanofibers both in yield and in cost.

Ternary Diffusion Coefficients of 1-Hexanol-Hexane-Toluene and 1-Propanol-Water-Ethylene Glycol by Taylor Dispersion Method

The Taylor dispersion method was used to measure diffusion coefficients of three-component liquid systems. An improved constrained nonlinear least-square method was used to evaluate the ternary diffusion coefficients directly by fitting the mathematical solutions of the dispersion equation to eluted solute peaks detected using a differential refractometer. Diffusion coefficients of the three-component system of acetone-benzene-CCl4, determined at 25℃, were used to test the procedure. The measured diffusion coefficients were compared with values obtained by optical interferometry and the diaphragm cell method. Ternary diffusion coefficients are also determinated for solutions of 1-hexanol-hexane-toluene and 1-propanol- water-ethylene glycol at 25℃, with an accuracy of approximately 0.05 m^2·s^- 1.

Preparation of Thermosensitive Microcapsules Containing Water Soluble Powder by Melting Dispersion Cooling Method

It was tried to prepare the thermosensitive microcapsules containing the water soluble solid powder by the melting dispersion cooling method and to establish the optimum preparation conditions. As a model water soluble solid powder, sodium hydrogen carbonate was adopted in order to generate carbon dioxide gas and as a thermosensitive shell material, olefin resin with the melting point of ca. 40°C was used. In the experiment, the concentration of olefin resin in the shell material solution was mainly changed together with the concentrations of the oil soluble surfactant species and the α-tocopherol as a modifier of shell. Addition of α-tocopherol into the shell material solution could prevent the core from breaking away during the microencapsulation process and result in the higher microencapsulation efficiency, because the dispersion stability of solid powder in the shell material solution could be increased due to the increase in affinity between the shell material solution and solid powder. Also, the microencapsulation efficiency increased with the concentration of olefin resin, became maximum at 50 wt% and then, decreased. The microcapsules were found to begin melting at 36°C and to generate carbon dioxide gas.

Gap States of ZnO Thin Films by New Methods:Optical Spectroscopy,Optical Conductivity and Optical Dispersion Energy

The optical reflectance and transmittance spectra in the wavelength range of 300-2500 nm are used to compute the absorption coefficient of zinc oxide films annealed at different post-annealing temperatures 400, 500 and 600°C.The values of the cross point between the curves of the real and imaginary parts of the optical conductivity ɑ_1 and ɑ_1 with energy axis of films exhibit values that correspond to optical gaps and are about 3.25-3.3 eV. The maxima of peaks in plots dR/dλ and dT/dλ versus wavelength of films exhibit optical gaps at about 3.12-3.25 eV.The values of the fundamental indirect band gap obtained from the Tauc model are at about 3.14-3.2 eV. It can be seen that films annealed at 600°C have the minimum indirect optical band gap at about 3.15 eV. The films annealed at 600°C have Urbach＇s energy minimum of 1.38 eV and hence have minimum disorder. The dispersion energy d of films annealed at 500°C has the minimum value of 43 eV.

Optimization of preparation process of cationic liposome nanoparticles containing Survivin-siRNA and osthol

Objective:To prepare cationic liposome nanoparticles loaded with survivin-siRNA and Cnidium monnieri based on the ability of liposomes to contain both water-soluble and lipid soluble components.Methods:The preparation technology of Osthol cationic liposomes was optimized by orthogonal test with membrane material ratio,drug lipid ratio,ultrasonic time and steaming temperature as factors.The volume ratio of HA-siRNA to protamine and the ratio of HA-siRNA protamine complex to liposome were investigated by control variable method with potential and particle size as indexes.The particle size and zeta potential were measured by potentiometric particle size analyzer,and the shape was observed by transmission electron microscope;The absorbance of different concentrations of FAM-Survivin-siRNA standard solution was measured by microplate analyzer,and the entrapment efficiency of cationic liposomes loaded with FAM-Survivin-siRNA and osthole was calculated.Results:The optimum preparation conditions of osthole loaded cationic liposomes were as follows:the ratio of membrane to material was 3:1,the ratio of drug to lipid was 1:5,the steaming temperature was 30℃,the ultrasonic time was 70 min,and the encapsulation efficiency was 78.34%.The optimum preparation conditions of osthole loaded cationic liposomes loaded FAM-Survivin-siRNA were as follows:the volume ratio of Survivin-siRNA to protamine was 1:1,Protamine complex 25μg.Add 50μL cationic liposomes.The particle size is 132.3±0.2nm,zeta potential is 43.15±0.05mv,and its shape is irregular round;According to the standard curve,the entrapment efficiency of cationic liposome nanoparticles co loaded with Survivin-siRNA and osthole was 81.34±0.041%.Conclusion:The prepared cationic liposome nanoparticles loaded with Survivin-siRNA and osthole have good encapsulation efficiency,particle size and zeta potential.

THE MICROSTRUCTURE AND COMPRESSIVE PROPERTIES IN NiAl(Co) MATRIX COMPOSITE

The microstructures of NiAl(Co)-TiB_2 composite prepared using exothermal dispersion (XD) method have been studied by optical microscopy, XRD, EDS, and TEM The results show that, TiB_2 paritcles are typically single crystal, and fairly uniformly distributed. The matrix mainly consists of β-NiAl phase, Ll_2γ′Ni_3Al phase and δ-Ni_3Al phase. The δNi_3Al has a fcc crystal structure with lattice parameter a=1.068nm.The data of compressive testing at room temperature show that the room temperature ductility of NiAl(Co) matrix composite is much better than that of stoichiometric NiAl.

半空间多层各向异性介质的面波频散方程

将地球物理学中各向异性研究的前沿课题同半空间面波问题结合在一起，用有限元方法建立了半空间多层各向异性介质的面波频散方程；同时，对该频散方程的有关问题进行了讨论，本研究对于勘探地震学和工程勘查具有理论意义和应用价值。

A novel chromatic dispersion monitoring method in terms of SO A spectral shift

In this paper a novel low power online chromatic dispersion (CD) monitoring method is presented, which employs spectral shift in the semiconductor optical amplifier (SOA). The advantage of this method lies in that the required input power can be much reduced, and the filter output can be used in the dynamic CD compensation system. The simulation indicates that the filtered power decreases with CD increases, and that the monitoring range increases as the filter bandwidth increases.

Optimum design of welding transformer

Welding transformer is widely used in industry manufacturing, depleting a large portion of electricity energy.Based on modern computer technology and mathematical programming, optimum design of electro-magnetic devices leads to highly efficient use of energy and materials. Are welding transformer is optimized here. A mathematical model,considering both productive cost and operating losses, which is called or Economical-through-Life transformer, is established. Mixed penalty function method, mixed dispersing variable method and improved orthogonal method have been applied to carry out the optimization calculations. Result shows that the power factor is quite important in an Economi-cal-through-Life transformer, and that some principles must be followed in the design work. Also discussed are the advantages and disadvantages of the three methods. In the end, the prospect of optimum design of welding transformer is forecast.

Viscoelastic modeling of the diffusion of polymeric pollutants injected into a pipe flow

This study focuses on the transient analysis of nonlinear dispersion of a polymeric pollutant ejected by an external source into a laminar pipe flow of a Newtonian liquid under axi-symmetric conditions.The influence of density variation with pollutant concentration is approximated according to the Boussinesq approximation and the nonlinear governing equations of momentum,pollutant concentration are obtained together with and Oldroyd-B constitutive model for the polymer stress.The problem is solved numerically using a semi-implicit finite difference method.Solutions are presented in graphical form for various parameter values and given in terms of fluid velocity,pollutant concentration,polymer stress components,skin friction and wall mass transfer rate.The model can be a useful tool in understanding the dynamics of industrial pollution situations arising from improper discharge of hydrocarbon pollutants into,say,water bodies.The model can also be quite useful for available necessary early warning methods for detecting or predicting the scale of pollution and hence help mitigate related damage downstream by earlier instituting relevant decontamination measures.

"External main and internal auxiliary" treatment on refractory radiation proctitis

Radiotherapy is an essential method in the comprehensive treatment of malignant tumors.However,radiation proctitis(RP)is a common complication of pelvic tumors after radiotherapy.Due to RP's various etiology and complex pathogenesis,it is currently no standard for traditional Chinese medicine(TCM)treatment.Professor Yuan-hong Zhao believes that refractory RP,which is named chronic hemorrhagic radiation proctitis(CHRP),should be classified as"Intestinal Wind Bleeding"(Bleeding like a note before defecation,bright red blood,no swelling and pain in the anus)and"Intestinal Afflux"(Refers to the symptoms of pus and blood in the lower mucus,similar to ulcerative colitis,peptic ulcer and other diseases in modern medicine.)in TCM.The critical pathogenesis of CHRP lies in local stasis and collaterals injury of intestinal collaterals.In general,it is a syndrome of excess and scarcity.External treatment with TCM is the preferred treatment strategy for CHRP,and the primary way is to disperse blood stasis and detoxify and nourish the intestinal collaterals.

A methodology to improve nanosilica based cements used in CO2 sequestration sites

Attempts to reduce the amount of greenhouse gases released into the atmosphere in recent years have led to the development of Carbon Capture and Sequestration(CCS)technology.However,there have been many studies reporting leakages form CO2 storage sites as a result of cement degradation induced by generation of an acidic environment in the storage site.Although there are a number of approaches proposed to enhance the efficiency of the cement,the degradation issue has not been totally resolved yet perhaps due to the excessive corrosives nature of carbonic acid and supercritical CO2.The aim of this study is to propose a methodology to improve the physical and mechanical characteristics of the cement by nanomodification such that a consistent rheology,constant density and a good strength development can be achieved.A new dispersion technique was proposed to ensure that the cement formulation gives a consistent result.The results obtained indicated that unlike the literature mixing,cement slurries prepared by the new mixing technique are very consistent in their rheology,regardless of the sonication parameters chosen.The measurements of the compressive strength performed at the reservoir condition revealed that nanosilica contributes in the strength development up to a certain point.Thermogravimetric Analysis(TGA)conducted at the last stage indicated that the amount of Portlandite left in the cement by adding nanosilica is decreased due to the pozzolanic reaction,which would help the cement to have a higher chance of survival in a storage site.However,cautions must be taken to maintain a certain amount of Portlandite in the cement for slowing down the carbonation rate,as otherwise the matrix of the cement is attacked directly and the cement will be degraded very fast.

Circulation intensity and axial dispersion of non-cohesive solid particles in a V-blender via DEM simulation

In this study, discrete element method （DEM） was employed to simulate the movement of non-cohesive mono-dispersed particles in a V-blender along with particle-particle and particle-boundary interactions. To validate the model, DEM results were successfully compared to positron emission particle tracking （PEPT） data reported in literature. The validated model was then utilized to explore the effects of rotational speed and fill level on circulation intensity and axial dispersion coefficient of non-cohesive particles in the V-blender. The results showed that the circulation intensity increased with an increase in the rotational speed from 15 to 60 rpm. As the fill level increased from 20% to 46%, the circulation intensity decreased, reached its minimum value at a fill level of 34% for all rotational speeds, and did not change significantly at fill levels greater than 34%. The DEM results also revealed that the axial dispersion coefficient of particles in the V-blender was a linear function of the rotational speed. These trends were in good agreement with the experimentallv determined values reported bv previous researchers.

A review of CNTs and graphene reinforced YSZ nanocomposites:Preparation,mechanical and anti-irradiation properties

Yttria stabilized zirconia(YSZ)ceramics have been widely applied in areas of high-temperature thermal protection and nuclear radiation protection during the past decades.Both carbon nanotubes(CNTs)and graphene are regarded as highly ideal reinforcements for YSZ ceramics due to their natural excellent properties.However,is still a controversial topic how to make YSZ composites obtain better performance after adding CNTs and graphene.In particular,dispersion and sintering processes of CNTs and graphene in YSZ,are critical to the performance of the YSZ composites.So far,there is not a thorough analy-sis of the impact of CNTs and graphene on the mechanical characteristics and irradiation resistance of YSZ.Therefore,this paper focuses on the dispersion methods and sintering technologies of CNTs/YSZ and graphene/YSZ nanocomposites,as well as the mechanical properties and anti-irradiation properties.Fur-thermore,the potential applications are also prospected for CNTs/YSZ and graphene/YSZ nanocomposites.

Synthesis and surface modification of the nanoscale cerium borate as lubricant additive

Nanoparticle of cerium borate with a size of about 50 nm was synthesized via sol-gel precipitation method under micro-emulsion by oleic acid,using Na2B4O7 and Ce（NO3）3 aqueous solution as raw materials,and the morphology and microstructure of as-prepared particles were characterized by means of scanning electron microscopy（SEM） equipped with an energy-dispersive X-ray spectrometer（EDS）,X-ray diffraction（XRD）,infrared spectroscopy（IR）,and thermogravimetric analysis（TGA）.Two methods to disperse the particles into base oil were employed,and the results derived from the four-ball tribotester indicated that the friction coefficient of the base oil by the addition of the nanoscale cerium borate particles diminished greatly,and the anti-wear properties also depended on the dispersion methods.