Search results

Introduction Natural gas hydrates (clathrate hydrate(s) of natural gas) are solid crystalline compounds in which water, at low temperatures and high pressure, forms a cage-like structure around gas molecules.
In this study, different architectures and training algorithms are used to find optimum structure of the neural network.
A number of training runs has been done until we find optimum RBFN structure.
Vuthaluru, "A novel correlation for estimation of hydrate forming condition of natural gases," Journal of Natural Gas Chemistry, vol. 18, pp. 453-457, 12// 2009
Ghiasi, "Initial estimation of hydrate formation temperature of sweet natural gases based on new empirical correlation," Journal of Natural Gas Chemistry, vol. 21, pp. 508-512, 9// 2012

Three polymorphic crystal structures of chitin and its deacetylated chitosan are known, α-, β- and γ-structure in nature [1, 2].
Due to its compact structure, α-chitin is insoluble in most common solvents and it is only limited swollen in alkaline aqueous solutions [2].
This remarkable difference in two types of chitin seems to be caused by relatively low crystalline or loosely ordered structure with weaker inter- and intramolecular hydrogen bonding in β-chitin compared to α-chitin [18, 19].
Roberts, in: Chitin Chemistry (edited by MacMillan Press, London 1992)
Zhang: Chemistry Bulletin Vol.3 (1992), p.39 [16] W.

Effect Of Bi Addition On The Electrochemical Behavior Of Zinc Electrodes In Concentrated Alkaline Solutions Liang Hongxia 1,a, Li Furong2,b ,Wang Zhilin 3,c 1Department of Resource and Environmental Engineering,Panzhihua University 61700,china 2Panzhihua University 61700,china 3State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry,Xiamen University, Xiamen 361005 China aemail:370499524@qq.com, bemail: 316709097@qq.com. cemail: 545942766@qq.com.
Since dissolution of crystalline structures typically proceeds layer by layer along the steps, the formation of solid particles along the steps may have an effect of blocking the sites for the dissolution reaction.
Increasing alloying concentration tend to increase the amount of surface active sites because it generally causes increasing inhomogeniety of the crystal structure, more displacement sites, vacant sites and misaligned regions such as grain boundaries.
In actual batteries the zinc anode is a porous structure made of zinc powder.
The effect of bismuth on the structure of zinc hot-dip galvanized coatings.

Their structural flexibility enables modulation of elasticity, rigidity, degradation rate, porosity, and surface chemistry, making them suitable for a broad range of biomedical applications [1].
Therefore, even subtle changes in surface chemistry or morphology can significantly affect protein adsorption, cell adhesion, proliferation, and differentiation.
Slightly hydrophilic surfaces have been shown to favor adhesion and spreading of human mesenchymal stem cells (hMSCs), promoting stable focal adhesions and organized cytoskeletal structures [17].
Polar component of the Surface Free Energy of structured PEEK samples, patterned with 4000 Hz and 6 kg of post-load (configuration d in Table 2), compared to the control group.
The process enabled the generation of highly accurate micrometric surface structuring while minimizing thermal effects on the polymer material.

In this paper, we employ software chemkin-4.5, concentrating our research on factors that may affect the treatment efficiency of reactor through simulating real chemical reaction and the structure of the reactor.
And the ion temperature in plasma system can be directly determined by user or be assumed as a constant. 2 Simulation Software and Model Structure 2.1 Simulation Software Introduced The numerical simulation of the low-temperature plasma synergistic catalytic reactor relies on software Chemkin 4.1.
Figure 1 The structure diagram of NTP and catalytic reactor for testing 2.2.2 Selection of network diagram of model Employing reactor of the plasma of one-dimensional plug-flow in the Chemkin-pro, showed in Figure 2.
(4)The simulation model is based on the source file's of CHEMKIN-PRO,taking the limitations of the input study of gas-phase chemistry and surface chemistry into account ,it may have a certain gap with the working condition of the actual low temperature ion synergistic catalytic reactor, and will eventually affect the output of the results.
Effect of Electrode Structure on the Parameters of Dielectric Barrier Discharge.

We present the characteristic modulated structures of nanoparticles and calculate the parameters of these structures.
Spiral structures, longitudinal and transverse spin-wave structures, fan structures, etc. were revealed.
Parameters of modulated nanoparticle structures.
Parameters for these structures are given in Table 2.
Cava et al, Future directions in solid state chemistry: report of the NSF-sponsored workshop, in: Progress in Solid State Chemisty. 30 (2002) 1-10

The obtained results confirmed the possibility of using marine macrophyte biomass for heavy metal biosorption and evidenced a strong dependence of lead and arsenic uptake on the macrophyte structure.
A first investigation was aimed at the study of macrophyte structure effect on lead biosorption equilibrium.
This bad sorption abilities might be related to the simple structure of the thallus [7]; - the two green algae species showed a similar behaviour, with a maximum uptake of about 60-70 mg/g for both Ulva species.
In fact, brown algae and seagrasses, known to have a more complex structure than green and red algae, were found to be the best sorbents for lead and also showed good sorption abilities for arsenic.
On the other hand, red algae, which have a relatively simple structure of the thallus and were the worst lead sorbents, resulted to be the best arsenic sorbents, in the investigated experimental conditions.

Hydrothermal Synthesis and Photocatalytic Activity of Mesoporouse TiO2 with High Surface Area and Different Pore Size Fengjiao Chen1, a, Zhaosheng Bu1,2,b, Guowei Zhou*1,c 1Key Laboratory of Fine Chemicals in Universities of Shandong, School of Chemistry and Pharmaceutical Engineering, Qilu University of Technology, Jinan 250353, China 2School of Chemical Engineering and Environment, Weifang University of Science and Technology, Weifang 262700, China afengjiaobaoche1987@163.com, bbuzhsh@126.com, cguoweizhou@hotmail.com Keywords: Mesoporous titanium dioxide, Surface area, pore size, Photocatalytic activity Abstract.
Mesoporous TiO2 with high surface area (SBET) and different pore size was successfully fabricated via hydrothermal method using cetyltrimethylammonium bromide and PEO-PPO-PEO as the structure-directing agents, and tetrabutyl titanate (TBT) as titanium source.
The crystal structures of the TiO2 powders were characterized by X-ray diffraction (XRD, Bruker Company) with Cu Ka radiation (40 kV, 40 mA, l = 0.15406 nm).
Morphology of cluster nanostructures was nearly spherical-shape, as structure-directing agents were added.
These results can be explained that P123 and CTAB promote accumulation of grain: when less TBT amount was added to system, accumulation was packed densely to form tight structure; more TBT amount brought grain density increase, thus hydrolysis of TBT can improve grain to escape the shackles of structure-directing agents and formed loose structure.

All the ceramics possess a pure perovskite structure, indicating that Bi3+ and Y3+ are incorporated into Ba0.85Ca0.15Ti0.9Zr0.1O3 lattices to form a solid solution.
The phase structure and microstructure of the sintered disks were characterized by X-ray diffraction (XRD, PANalytical Xpert) and SEM (JSM-5900), respectively.
As can be seen from these patterns,all samples have single phase of perovskite structure, and nosecondary phase could be observed in BCZT-BY ceramic samples sintered at different temperatures.
This indicates that the BY has completely diffused into the BCZT lattice and thus maintained the perovskite structure of BCZT solid solution.
Conclusions The 0.996(Ba0.85Ca0.15)(Zr0.1Ti0.9)O3-0.004BiYO3ceramics sintered at different temperatures arepossess the single perovskite structure.

Ca3Co4O9 have the same structure with NaCo2O4.
All the particles are presented in a form of lamellar structure [11].
The particles present lamellar structure with the grain size of 200 nm ~ 1.5 μm.
Modulated Structure of the Thermoelectric Compound [Ca2CoO3]0.62CoO2, J.
Inorganic Chemistry.49(2010) 3216-3223