Advanced Materials Research Vols. 779-780

Abstract: In the present paper, nano-scale magnesium hydroxide has been prepared at low temperature via a wet chemical process using MgCl₂· 6H₂O (or Mg(NO₃)₂) and NaOH as the starting reagents under normal pressure. The fresh synthesized magnesium hydroxide nanocrystals were characterized by X-ray diffraction (XRD), selected area electronic diffraction (SAED) and transmission electron microscopy (TEM) measurements. Patterns of XRD and SAED exhibited that the products were high-quality hexagonal crystal system nanocrystals. Though the TEM pictures, large quantities of lamellar-like and needle-like magnesium hydroxide nanocrystals could be observed without obvious aggregation. Using the present method, high yield magnesium hydroxide nanoparticles would be produced without expensive equipments like the high temperature and high-pressure reactor.

Abstract: In the current paper, hydroxyapatite (HAP) nanorods have been synthesized via a precipitation method with membrane separation technique assisted. The reactants were Ca(NO₃)_{2 ·}4H₂O, NH₄H₂PO₄ and ammonia water. The synthesized HAP nanocrystals were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements. Patterns of XRD exhibit that the products are indexed high-quality hexagonal crystal system nanocrystals. Though the TEM pictures, large quantities of HAP nanorods could be observed with a length of about 50-80nm and a diameter of about 10-20 nm. Preliminary study on the membrane based purifing process is also discussed by comparion the membrane of molecular weight cut-off 6000 to 10000. The resulting HAP nanorods have extensive use in biomedical area such as the bone graft substitute, drug delivery system, carrier for gene transfection, and etc.

Abstract: The study on separation of nickel ions with S.D.D from six kinds of solutions or systems was conducted. One of six kinds of systems was prepared with the solution (called as original solution here) leached from pyrolusite with pyrite and H₂SO₄, and the other five kinds of systems were prepared with analytical reagents, they are respectively: a monophyletic system of NiSO₄, two binary systems of MnSO₄NiSO₄ and (NH₄)₂SO₄NiSO₄, a ternary system of MnSO₄(NH₄)₂SO₄NiSO₄, a pentanary system of MnSO₄(NH₄)₂SO₄NiSO₄CoSO₄ZnSO₄. The experiments about reaction time and S.D.D dosage were conducted. Results showed that the equilibrium time of reactions for the prepared five systems were equally 10min at most, while 3h was needed at least for original solution under the conditions of low temperature and low stirring speed. The residual nickel ion concentrations of the six systems were different when the same multiples of S.D.D theory dosage of each system was used for separation of nickel ions, and the S.D.D dosages for the six systems needed to meet the requirement of electrolysis were also different.

Abstract: The factor and technology of synthsis dimethyl ether by one step method were studied in slurry reactor with bi-function catalyst by phophorus modified (C301/ P-γ-Al₂O₃) and liquid paraffin. The results showed that the temperature, pressure, space velocity of reaction system and CO₂ content in the syngas have a greater influenced to synthsis dimethyl ether. The CO conversion per pass reached 93% and DME selective was more than 60% at 150mL liquid paraffin catalyst for solvent quality of 7.3%, H₂ (mol) to CO (mol) of 2, 270°C, 4.3MPa, space velocity of 600mL/h·g_cat. The existence of CO₂ in the syngas improved the produce yield of dimethyl ether.

Abstract: According to the properties of cleancool fiber, two different kind of fabrics for sportswear were designed in this paper first, then fabrics properties of bursting strength, air permeability, ygroscopicity and anti-bacterial Property were test, and according to the test results, the durability performance, thermo-hydro comfortbility and anti-bacterial property of the developed fabrics were analyzed. The analyzing results indicated that developed fabrics have excellent performance and they are suitable for making high quality sportswear .

Abstract: The paper presents the structural characteristics of solid wastes separation sieve. Pieces of plastic film and sandstones with different friction factors and elasticity coefficients are chosen as the research objects. The motion and the separation mechanism of materials in the sorting process are studied. According to the motion analysis on pieces of plastic film and sandstones on solid wastes separation sieve, it can be concluded that the materials with different friction factors and elasticity coefficients can all be sorted by solid wastes separation sieve. The more difference they have in friction factors and elasticity coefficients, the better separation performance can be achieved. The selection and calculation on the kinetic parameters of solid wastes separation sieve is carried out, which provides the theory evidence for the design of new friction sorting equipment and opens up new prospects for the application of solid wastes separation sieve.

Abstract: This study was conducted to discover the relations between thermal property of building materials and people's physiology and psychology. Heart rate variability of electrocardiogram ( ECG ) and alpha, beta, theta waves of electroencephalogram ( EEG) were examined in ten adult healthy volunteers. And also a combined analysis on inner correlations among physical parameters of material, human physiological indexes and subjective rating was proceeded. Physiological experiment research was carried out in environmental science laboratory. Environmental stimuli derived mainly from the building material to be tested. The results suggest that the density and coefficient of thermal conductivity are decisive effect factors on the physiological changing degree of human.

Abstract: Magnetic fluid is the key core of magnetic fluid sensor. Here magnetic model of magnetic fluid is analyzed. The magnetic curve of magnetic fluid is divided into 3 parts and the liner area is presented to make magnetic fluid sensor more sensitively. The magnetic force of magnetic fluid in magnetic field is calculated and analyzed. The magnetic permeability of magnetic fluid in sensor could be treated as a constant in the linear area of magnetization curve. And the magnetic force of magnetic fluid in magnetic field could be ignored if the length to diameter ratio of the solenoid is large enough.

Abstract: For a better design of Jet Grouting (JG) and Cutter Soil Mixing (CSM) technologies, a set of laboratory formulations are usually prepared aiming to give a first idea of the mechanical behavior of the final mixture. However, these formulations can represent an important cost to the project. Therefore, aiming to reduce such cost, in the present work the analytical expressions proposed by Eurocode 2 for strength and stiffness prediction of concrete were adapted to soil-cement laboratory formulations for JG and CSM projects. It is shown that these expressions can be successful applied in mechanical properties prediction over time of soft soil stabilized with cement for a wide range of cement content, water cement ratios and soil types.

Abstract: The chemical modified jute fibres were spun into jute/cotton blended yarns by using of two different blending methods (the fibre blending and the sliver blending) on ring spinning system. The tensile, hairiness, Uster evenness properties of two kinds of blended yarns with different blend ratios and yarn counts were investigated in this paper. It was found that the tensile, hairiness index, mass irregularity and imperfections of blended yarn depended on amount of jute fibres in blends. The draw frame blended yarns processed the better quality than that of intimate blended yarns.