Search results

Nonisothermal crystallization kinetics of isotactic polypropylene filled with a novel nucleating agent Nai Xu1,2,a, Lisha Pan1,2,b*, Sujuan Pang1,2,c, Qiang Lin3,d 1 College of Materials and Chemical Engineering, Hainan University, Hainan, Haikou 570228, China. 2 Hainan Provincial Fine Chemical Engineering Research Center, Hainan University, Hainan, Haikou 570228, China. 3 College of Chemistry and Chemical Engineering, Hainan Normal University, Hainan, Haikou, 571158, China.
It is well known that the mechanical properties of iPP are largely related to the crystal structure and morphology, which in turn depends on the crystallization conditions and nucleating agents (NAs).
In our previous paper[3], the effect of TMC328 on crystallization behavior and crystal structure of iPP were reported.
Pukanszky, in Polypropylene Structure, Blends and Composites, Vol. 3, J.

However, the addition of roughness to the surface can increase the contact angle of water without altering the surface chemistry [3].
The presence of an uneven petal structure can be observed with pore diameters ranging from 200 to 900 nm and fibber length from 500 nm to several micrometers (Fig. 1b), resulting in a rough surface with porous structure.
Figures 3c-3d show the formation of a foam-like coating structure on stearic acid-CaCO3 nanoparticle surface for which there is a remarkable change in the surface morphology.

The fracture surface of the glass adhesive layer was fairly smooth which indicated a glassy, brittle structure.
This image showed that the molten glass adhesive does penetrate the alumina structure, which would indicate sufficient wetting of the alumina by the glass and also, that any excess glass remaining at the adhesive layer does fail in a brittle fashion.
Kashiwagi, Thermal Decomposition Chemistry of Poly (vinyl alcohol), in G.
Uspenskaya, Structure and glass transition temperature of sodium-silicate glasses doped with iron, J.

Introduction In concrete works their own weight is a very large part of the load influencing the structure, so decreasing the concrete´s specific mass becomes of major interest.
Strength is normally a general indication of concrete´s quality, being in direct relation with the hardened cement mass structure, so concrete´s characteristics must be defined by its ability to stand mechanical stresses it will undergo as well as durability issues [3].
In recent decades, numerous structures were seen to have been impaired as a result of durability issues, indicating the urgent need to widen materials and constructive methods research focusing on the quality of concrete, external attacks that might affect it and surface protections.
Advances in chemistry in recent years have enabled numerous of types of protection to be developed ensuring durability by reducing water absorption, penetration by salts and aggressive gases, provided the proposed protections are periodically inspected to see if they need renewing, for them to keep functioning [4].

Belous1,e, 1Institute of General and Inorganic Chemistry, Palladina avenue 32/34, 03142 Kyiv, Ukraine 2LUNAM, Institut des Molécules et Matériaux du Mans (IMMM UMR CNRS 6283), Université du Maine 72085 Le Mans Cedex 3National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan ayelenicho@ukr.net, bsolopan@ukr.net, ckolodiazhnyi.taras@nims.go.jp, djean-marc.greneche@univ-lemans.fr, ebelous@ionc.kar.net Keywords: diethylene glycol, microemulsion, nanoparticles, cryochemical synthesis.
Belous, Polyol Synthesis and Properties of AFe2O4 Nanoparticles (A = Mn, Fe, Co, Ni, Zn) with Spinel Structure, Solid State Phenomena 200 (2013) 149-155. ].
The X-ray diffraction revealed that the nanoparticles obtained are characterized by a cubic spinel crystal structure (JCPDS Card Number 19-0629 [[] Y.
It is important to emphasize that the hyperfine structure at 300K allows to be decomposed into two components ascribed to both maghemite and goethite phase, the second one well characterized by its typical quadrupole shift -2e = 0.23 mm/s.

It has special structure and excellent physical and chemical properties.
Among the conducting polymers, polyaniline(PANI) being cheap and easily obtained monomer[2-3] with special structure and excellent physical and chemical properties, it has extensive and in-depth prospect in the second battery, metal corrosion, sensors, capacitors, electromagnetic shielding and anti-static fields[4-8].
These results showed the crystal structure of nano-silver was successfully obtained.
References [1]Li Yongfang: J Progress in Chemistry.

Bradley 1 1 Department of Chemistry, University of Hull, Cottingham Road, Hull, HU6 7RX, UK 2 Laboratoire de Chimie Organométallique de Surface, 43 Bd du 11 Novembre 1918, 69616 Villeurbanne Cedex, France Keywords : Silicon boron imide; Gel; Pyrolysis; Silicon boron nitride; Mesoporous materials.
Both of the composite materials exhibited mesoporous structures with surface areas of 439 and 788 m2/g, respectively.
The major component with a isotropic chemical shift at 26 ppm for gel 2a and 29 ppm for gel 2b can be ascribed to the borazine -like ring structures coming from the precursor molecules.[16] The other two components show isotropic chemical shifts at about -2 ppm and 14 ppm, which are similar to those found for polyborosilazane reported by Jansen and coworkers [9] and ascribed to the formation of trigonal planar coordination of boron by nitrogen, probably due to the breaking of the borazine rings in the precursor molecules during the gelation process.
Physisorption analysis (Fig.3 and 4) indicates that both solids exhibit mesoporous structures (type IV nitrogen adsorption isotherms) with surface area of 439 m 2g -1 (solid 3a) and 788 m 2g -1 (solid 3b).

Subsequently, the slurry was injected into the mould which made from glass, as a result, the monomer and the cross linker were activated by initiator and catalyst and reacted to form a three-dimensional network structure which made the in-situ solidification of the ceramic powders slurry.
After the gelation for 10mins and demoulding process, a homogeneous wet green ceramic body with uniform chemistry and density that contained only a few percent organic binder was prepared.
On the other hand, this kind of structure of the green body also has the advantage of the removal of the monomer and the cross-linker which avoids the surface crack during the process of drying and sintering.
Dry press forming can not avoid the conglobation of ceramic powders and result of heterogeneous structure of the green body, and also, as a integrated arc -sharp plate, the arc-shape mould makes the spreading powders process very difficult, as far as hot isostatic press forming is concerned, a circular mould with diameter of 800mm must be required for preparation such an arc-shaped integrated ceramic plate with size of 300 × 250 × 6 mm, R400 mm, that would result in high capital equipment cost, operating difficulties and low productivity.

The leakage current and clamping of the domain walls by oxygen vacancies make ferroelectric materials unsuitable for practical applications.[13,14,15,16] Therefore, materials design based on defect chemistry is essential for fabricating high-quality Bi-based devices with superior piezoelectric properties.
Jones and Thomas have reported that BNT has tetragonal P4bm structure with a small Ps that is an intermediate phase between low-temperature rhombohedral R3c and high-temperature cubic phases.[6,7] The unit cell of the tetragonal P4bm structure has √2a×√2 a×c of cubic unit cell and includes two kinds of different crystallographic Ti ions.
This crystal structure gives rise to Ps along the c axis and leads to a possibility of ferrielectricity (the local ionic polarizations are opposite with different values and Ps can be switched by applying an E).

Geopolymers are then formed with tightly packed polycrystalline structure so as to give better mechanical properties.
The reaction mechanism involves the dissolution of Al and Si in the alkali medium, transportation of dissolved species, followed by polycondensation, forming a 3D network of alumino-silicate structure.
When Si/Al > 1, the silicate species formed as a result of hydrolysis of SiO2, tend to condense among themselves to form oligometric silicates whose condense with Al(OH)4- forming a rigid 3D network of geopolymer structures[15, 16].
Radke: The Journal of Physical Chemistry.