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College of Resource and Environment, Shaanxi University of Science & Technology, Xi’an Shaanxi, China，710021; 2.College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 ayanjing915@163.com, b429431766@qq.com Keywords: electrospinning; magnetic nanoparticles; high magnetic sensitivity Abstract.
Electrospinning is a polymer processing technique [7] that can control secondary structures of nanofibers.
Electrospun nanofibers have a uniform structure with various ingredients homogeneously distributed on the polymer matrix [9].
The internal structures of Fe3O4@SiO2 magnetic composite particles were deserved by transmission electron microscope (TEM) (H-800, Hitachi, Japan).
From the SEM images we can clearly observe the surface morphology of the electrospun nanofibers that all the fibers have uniform structures and smooth surfaces.

Introduction Aerobic granular sludge was sphere-like, denser aggregates with high activity which form from microorganisms, intertwining and gathering mutually under certain condition, which is provided with stronger microbial aggregate structure and excellent sludge settle-ability and a special form of biofilm[1,2].
Moreover, volatile fatty acids in aerobic granular system were detected to investigate its influence to environment, microbial metabolites in sludge were detected in order to speculate their community structure.
Chemistry oxygen demand (COD) was detected with rapid digestion method was determined by the catalytic oxidation method (Shimadzu TOC-VCPH).
The sludge morphology and structure were observed by using optic microscope (XSJ-HS type) and environmental scanning electron microscope (Phillips XL30).
Biodegradation of MTBE with ethanol co-substrate using an SBR and microbial community structure, Acta Scientiae Circumstantiae. 28 (2008) 2206-2212

Due to lack of point symmetry in its wurtzite structure, ZnO is piezoelectric.
Among other processing techniques for preparing ZnO nanoparticles, wet-chemistry sol-gel technique is well-known as simple and cheap method.
Based on Fig. 1a, it can be seen that the dried sample without pre-hydrothermal treatment (trace i) did not provide any peaks which can be assigned to the wurtzite structure of ZnO.
Instead, it demonstrated several small peaks belong to zinc-acetate () and hydro-zincite structures ().
All these peaks can be indexed successfully as (100), (002), (101), (102), (110), (103), (200), (112), (201) and (004) crystal planes of wurtzite structure ZnO ().

The main structure of coal gangue—Al2O3, SiO2 may change by erosion in alkaline circumstance, which can provide favorable conditions in the process of forming gel materials.
Ye Danian held that the activity of Al2O3 and SiO2 was essential in cement product, from the crystal chemistry, the admixture of cement must hold the cleavage silico-oxygen tetrahedron skeleton.
Coal gangue always contains carbon more or less, and carbon may have negative influence for cement product, after calcining, the internal structure would change and the impurities（C, Fe）could be removed, so as to increase the activation.
Song Xuyan[3]found that when compared with calcined samples, the structure of un-calcined sample was relatively compact, while the calcined samples presented loose state and the activation increased accordingly.
Meanwhile, the surface of particles would possess dislocation, point defects , structure defects, so after mechanical force action, the activation could increase accordingly.

The cartridge design allowed removing the solution-melt off of the structure at the temperature of the end of growth.
The optimal combination of the growth temperatures range and the composition of the initial liquid phase should be selected depending on the specific purpose of the grown structures.
The obtained results and techniques, used and proposed in this paper have both scientific and practical significance in the manufacture of semiconductor structures.
As well, the same patterns are typical in the manufacturing of intelligent engineering materials (thin doped layers, micro- and nano-structures, etc.).
The Ga-GaAs-GaP system: phase chemistry and solution growth of GaAS 1-X P X.

Since it was found in 2004 [9], graphene became one of the hottest topics in pure and applied physics, chemistry and materials science, and has attracted more and more attention.
TEM was also employed to determine the interior and wall structures of the carbon nanotubes.
The graphene sheets, consisting of a thin wrinkled paper-like structure, can be detected in the Fig. 1(c).
In respect of the graphene sheets, one may consider that it could be easy to form a porous structure in the macroscopic scale due to the curled and wrinkled graphene sheets stacked structure [15].
Figure 1(c) insertion demonstrated the two-dimensional ultrathin flexible structure of graphene.

Under the effects of these dynamic loads, the defects are more easily occurred in offshore jacket platform, thus resulting in the overall structure damage and serious marine accident.
Table 2 Groups of the optimum laser processing parameters Current (mA) Pulse width (ms) Frequency (HZ) Scanning Speed (mm/s) 160 10 8 1.0 160 10 8 1.5 160 10 8 2.0 170 10 8 1.5 Experimental Results and Analysis Influence of Laser Welding Processing Parameters on Structure of the Welded.
It can be seen that, with the increase of scanning current, the structure of welding zone gets more and more thick.
Djanarthany and et al. : Materials Chemistry and Physics, Vol.72 (2001), pp:301-319

Basically, protein is often categorized as functional and nutritional ingredients in food or feed instead of industrial structure elements.
As the MBA content increased more than 0.2wt%, a higher crosslinker content will produce more crosslinked points in polymeric chains, cause a higher crosslinking density, and decrease the space between the copolymer chains to form a highly crosslinked rigid structure, which cannot be expanded easily and hold a large quantity of water.
As we know, the hydrophilic units fixed on the hydrogel backbone contribute to the ionic charges in the swelling polymeric structure and the swelling of an anionic superabsorbent polymer is mainly caused by the electrostatic repulsion of the ionic charges of its network.
Flory, Principles of Polymer Chemistry, (Cornell University Press, Ithaca,NY 1953) [10] K.

Effects of Hard Segment Contents on Dynamic Mechanical Properties of Gap-based Polyurethane Elastomers Hai-qin Ding a,Le-qin Xiao b, Wei-liang Zhou c,li-rong He d,Huai-long Zhang e School of chemistry and Engineering,Nanjing University of Science and Technology,210094 Nanjing,China, adinghaiqin0816@yeah.net, bleqinxiao@hotmail.com, c121787089@qq.com, chelirongnjust@hotmail.com,ezhhlchxjx@qq.com Keywords：GAP; hard segment contents; mechanical property; fragility parameter; fractional free volume.
And the main chain of GAP is polyether structure .GAP has some merits such as plus heat of formation, big density, low mechanical sensitivity and well stability[1,2].Gap-based polyurethane elastomer(GAPE) is expected to meet the requirements of energy and mechanical performance of modern gun propellants ,which will be the research emphases on energetic binds for propellant abroad.
Based on the time temperature superposition principle of dynamic mechanical performance, constants C 1 and C 2 of WLF equation were obtained, then the fragility parameters and activation energy of GAPE were calculated form C1 and C2.The differences of toughness and rigidity of GAPE with different hard segments contents were explained form the point of view of molecular structure. 1 Experimental 1.1 Materials Glycidyl azide polymers was obtained from the 42nd Institute of The Fourth Academy of CASC (GAP, molecular weight (Mn) = 3430g·mol−1.4’4-Diphenylmethane diisocyanate was supplied from Chemical Co.
Moleculara structure of the ideal solid propellant binder.

This optimum performance can be achieved by the application of the better lubricating oil with enhanced characteristics that can provide a better surface chemistry of the bearings.
Adhvaryu et al. [13] studied the chemical structure influence that can happen on soybean oil’s teribochemical behaviour through the use of chemical and thermal modifications.
From the results, it was observed that when there was a rise in polar functionality for the vegetable oil structure, wear protection tended to be positive affected.
The mixing process is rudimentary in nature and was achieved at room temperature (20 ᵒC) until homogenous structure was attained.