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Recent analyses of coal structure have suggested that high-rank coals where carbon content is higher than 84%, micro-porosity dominates yielding an average pore diameter of less than 2 nm [2,14,15].
Such observation is in agreement with the porous structure of the high rank coals which is dominated by micro-pores, while lower rank coals with carbon content <75% contain mainly macro-pores [2,14,15].
Following work of Gensterblum et al. [2] who have suggested that small poro-elastic changes in cleat aperture may result in enhancement of slip flow, this observation could be related to the effect of effective stress on the cleat aperture where due to compressible structure of the coal, cleats become narrower which for a constant mean gas pressure, i.e. constant mean free path length of gas molecules, enhances the effect of slip flow.
[22] Information on: http://webbook.nist.gov/chemistry/fluid [23] S.

As they are also exceptionally durable responders to water chemistry, such as the temperature, conductivity or ionic composition [5], and alkalinity.
There are many factors to limit size of diatom, and it was shown that Silica is often a major limiting nutrient for diatom growth because it is necessary for the siliceous structures in diatom valves [19].
It is worth mentioning that the water in the upper reaches of Li River was in the status of cleaning and balanced structure of ecology with proper portion of different kinds of species, especially in the reaches of Guilin section.
[16] DENG hong-ping, community structure of diatom in Nanchong Section of Jialing River and analysis of its water environment, 2008, 4th, p 586-590

Introduction The studies aimed at establishing the structure formation patterns of a clinkerless cement stone of alkaline activation confirm the opinion of numerous scientists [1 - 5] that to obtain a strong and durable composite, components of aluminosilicate and silica nature, mixed with an alkaline solution, are required.
This type of binder bond is characteristic of powders made of limestone, sandstone, volcanic tuff, quartz flour, silicified marl, and quartz and dune sand, it is obtained to accelerate the hardening process and gain strength, catalysts should be introduced into the system, otherwise, under normal conditions, the formation of the structure is delayed for a long time, yes and the resulting composites are unlikely to have hydraulic capacity.
Krivenko Operational properties of concrete on slag-alkali cement, Building materials and structures (1980). 4.
Chemistry and applications (2008)

The authors are grateful for the porphyrin compound received from the research team of the Institute of Chemistry "Coriolan Dragulescu".
Amoruso: 6 - Plume characterization in pulsed laser deposition of metal oxide thin films, In: Metal Oxides, Metal Oxide-Based Thin Film Structures, edited by N.
Făgădar-Cosma: Structured Thin Films Based on Synergistic Effects of MnTa2O6 Oxide and bis-Carboxy-phenyl-substituted Porphyrins, Capable to Inhibit Steel Corrosion Processes Vol. 9 (2021) p. 1890 [16] M.
Fagadar-Cosma: Structured Thin Films Based on Synergistic Effects of MnTa2O6 Oxide and bis-Carboxy-phenyl-substituted Porphyrins, Capable to Inhibit Steel Corrosion Processes Vol. 9 (2021), p.1890.

Influence of Voids on Dimensional Accuracy and Stability in Bonded Metal-Composite Hybrid Joints Radim Kupcak1,a *, Jan Zouhar2,b and Radek Prikryl3,c 1Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno, Czech Republic 2Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno, Czech Republic 3Faculty of Chemistry, Brno University of Technology, Purkynova 464, 612 00 Brno-Medlanky, Czech Republic aRadim.Kupcak@vutbr.cz, bJan.Zouhar@vut.cz, cprikryl@fch.vutbr.cz Keywords: precision bonding, epoxy, voids, computed tomography, carbon fibre, composite materials Abstract.
Composite structures often require bonding, as it is not feasible to manufacture an interface on composite materials that would allow for precise positioning of mating parts.
Since optical instruments predominantly utilize rotationally symmetric lenses, the associated mechanical structures are also generally rotationally symmetric.
Beukers, Analysis and evaluation of bondline thickness effects on failure load in adhesively bonded structures, J.

Utilization of Calcium Alginate Silica Based on Coral Skeleton and Wedi Awu Beach Sand as NaCl Adsorbent Al Izza Hafilah1,a Alif Alfarisyi Syah1,b Anugrah Ricky Wijaya1,c Irma Kartika Kusumaningrum1,d Neena Zakia1,e 1Departement of Chemistry, Faculty of Mathematic and Natural Science, Universitas Negeri Malang aAl.izza.2003326@students.um.ac.id, balif.alfarisyi.2203328@students.um.ac.id, c*anugrah.ricky.fmipa.
Calcium carbonate (CaCO3) is an inorganic mineral with a porous structure that can be used in the adsorption process [9] [10].
So, this peak can identify that the silica structure in the beach sand is in the form of quartz crystals with a peak of 26.81.
FTIR results of Wedi Awu Beach Sand Silica Synthesis of Calcium-Alginate-Silica Gel The mechanism of calcium alginate silica synthesis takes place in 4 stages, namely (1) the formation of sodium alginate, (2) silica, (3) the formation of sodium alginate when reacting with silica, mixing sodium alginate solution with silica will cause the SiO2 surface to interact with the -O- group of sodium alginate to form a new structure. the mixture is white in color indicating that silica dispersed in sodium alginate, and (4) sodium alginate silica is dripped into CaCl2 solution from coral skeleton and forms Ca2+ crosslinks.

Chemical structure of methylene blue.
Chemical structure of Toluidine Blue O.
Chemical structure of Indocyanine Green.
Chemical structure of Hematoporphyrin.
Chemical structure of Curcumin longa L.

Fig. 2 Crystalline structures of both (a) half and (b) full Heusler alloys; C1b and L21 structures, respectively.
Atomically disordered structures, (c) B2 and (d) A2, are also shown (http://www.riken.jp/lab-www/nanomag/research/heusler_e.html) 3.2 C1b Structure: The C1b structure is similar to the L21 structure adopted by the full Heusler alloys, like Ni2MnSb where the X site is occupied by a Ni atom.
The C1b structure has Fm3m space group symmetry (225).
The B2 structure is treated as more disordered structure as compared to the L21 structure and it shows antiferromagnetic behavior.
This shape-memory alloy (SMA) is now called Nitinol (NiTi) and is the commercially most known SMA [62].This alloy exhibits excellent shape-memory characteristics and can have variable transformation temperatures by changing its chemistry or composition [63, 64].

This research is likely to have widespread applications in the oil and gas industry for predicting more accurate corrosion rates. 1.0 Introduction Improving the quality of corrosion rate prediction in determining the design life of industrial structures and all of the associated safety, health, environmental, and economic repercussions has been strongly motivated by a deeper comprehension of corrosion phenomena and the development of corrosion rate predictive tools [1–3].
The complex chemistry of water, the formation of its surface layer, its multiphase movement, and its high temperature and pressure are additional factors.
Research was also conducted to study the corrosion of steel in other structures used in the oil and gas industries.
The peak in the corrosion rate is usually seen between 60 and 80 °C, depending on water chemistry and flow conditions [30].

Rare earth doped and dehydrated zeolites X and Y, which are readily formed by aqueous ion exchange, were treated with a series of volatile fluorides containing precursors: (ammoniumfluoride, NH4F and NH4HF2 respectively; trifluoroacetic acid, CF3COOH, 'tfa'; hexafluoracetylacetone, F3C-CO-CH2-CO-CF3, 'hfa' ; perfluormethylsulfodiimine, H[(F3C-SO2)2N], 'pms'; (for the structures see Fig. 3) and the sol-gelmaterials by infiltration of the corresponding complexes from solution or the gas phase.
Practically independent of the rare earth content, analytically ratios of 5 to 6 F per rare earth ion are obtained, while the crystal structure of the zeolite is mostly conserved (XRD).
Under conditions similar to the zeolite chemistry described above, no evidence for particles < 5 nm was found.
The open pore structure of the sol-gel matrix is also suited to secondary surface modification.