Saturate formation water to the sand pack which permeability is 2 μm 2 by 1 mL/min at 75 ˚C. First, inject 0.3 VP cationic polymer solution to the core sample, and put it in constant temperature water bath for 8 h and water flooding 2 VP. Then inject 0.3 VP anionic polymer solution and put it in constant temperature water bath for 6 h and water flooding 2 VP. Determine the permeability of the core. Then repeat to inject the profile control agent alternatively like that until the permeability is stable. We change the injecting order of the profile control agent, first inject anionic polymer solution then cationic polymer solution. As the rounds of injection increases, the plugging rate can be shown by Figure 5. Figure 5 shows that alternative injection of anionic and cationic poly- mer has good plugging capacity, and all the plugging rates exceed 89%. With the increase of injection rounds, sealing capacity gets better. The plugging rate changes slightly after 3 rounds, because the adsorption achieves saturated. Considering the input-output ratio comprehensively, the rounds should not be more than 3. Preferen- tial injection of cationic polymer is better than preferential injection of anionic polymer. Meanwhile we can use this method to inject counter-ionic polymer into the formation in order to reuse the residual polymer in the for- mation.
In general, the future of polymer matrix composites is bright. The engineering community is now in the second generation of applications of composites, and primary structures are now being designed with these materials. There is a growing confidence in the reliability and durability of polymer composites and a growing realization that they hold the promise of economic as well as engineering gain. Commercial programs such as high speed civil transport will not succeed without the use of polymer composites. Integrated synthesis, processing, characterization, and modeling will allow the use of molecular concepts for the design of the material system and to estimate the effect of how the materials are put together on the performance, economy, and reliability of the resulting component. A more precise understanding of the manufacturing, processing, and component design steps will greatly accelerate the acceptance of these advanced materials. New horizons for properties and performance, for example, in smart and intelligent materials, actuators, sensors, high temperature organic materials and multi component hybrid systems, will involve the potential of introducing a new age of economic success and technical excellence. It has been estimated that finished product businesses already exist for the aggregate of polymers, reinforcements, prepregs, tooling machinery and other ancillary products.
Application of cheap domestic materials found in Kazakhstan – VEMA will allow simplification of the synthesis and decrease the cost of redox-polymers. Possibility of their multiply regeneration and decrease of the transportation expenditures will compensate production costs. Besides that, existence of amino group in the structure of VEMA excludes additional amination stage, gives hydrophilic properties to the polymer and improves kinetic properties. Due to the complexing and redox properties of the polymers they can be used as oxidants, deoxidants and dehydrating agents in chemical industry and hydrometallurgy for the separation and concentration of heavy and noble metals ions, waste water treatment, catalysis and to solve variety of ecological problems. Atomic absorption analysis is one of the most precise methods used to study sorptive power of polymers. Sorption of metals from НСl solution with normal concentration equal to
|| O results reveal that, synthesized polyesters have high thermal stability than polyamides. The fully aromatic polymers showed better stability than semi-aromatic ones. The higher thermal stability of polymer BETP could be attributed to the incorporation of azomethine, oxadiazole ring and fully aromatic nature of the polymer backbone. The higher thermal stability is due to the intense chain stiffness and intermolecular hydrogen bonding of azomethine groups between the neighboring chains. Introduction of performed oxadiazole ring, phenylation of polymer backbone and symmetry of the structures are the most important structural modifications for increase in thermal stability (char % yield 47.2 at 800°) 22 .The glass transition
In the past decade, the interest in repair and retrofitting of existing structures and rehabilitation of the damaged structures has led to the development of more effective and low invasive architectural and engineering strategies. In this aspect, the application of fibre reinforced polymer (FRP) strengthening techniques has become reasonably widespread as suitable solutions in addition to the traditional ones. They are promising techniques because of their key characteristics such as: high specific strength, high stiffness, small thickness compared to conventional materials, low influence on the global mass, little durability concerns, ease of handling, flexibility and fast installation that improve on-site productivity, and have a low impact on building functions. In this context, the use of carbon fibre reinforced polymers (CFRP) and glass fibre reinforced polymers (GFRP) for the rehabilitation of damaged small masonry walls (here called wallettes) was investigated experimentally. This study sought to measure the maximum loading carrying capacity of the wallettes and to assess the possible structural rehabilitation in the damaged masonry structures after their reinforcement with the composite polymers. For the adhesion between the wallettes and the reinforcement fibres, primer, putty and a saturant glue epoxy resins were used. Debonding between the FRP composites and the substrate has been recognized as the primary failure mechanism of this reinforcement system and it occurs when the system shear capacity is reached and the FRP is detached from the element. This phenomenon is also addressed in this paper. In general, the experimental results showed the recovery of the original compressive loading bearing capacity of the structures, in spite of the debonding of the FRP composites. Moreover, it could be observed an increasing of up to 39% and up to 49% of the compressive strength for the damaged masonry wallettes reinforced with CFRP and GFRP systems, respectively. The recover (or even rise) in the loading capacity of the reinforced structures due to the external fibres bonding is a good indication of their effectiveness in these situations.
Polymer heat exchanger technologies are very advanced. However, if we compare the thermal and chemical properties of polymers in Table 1 with those of metal alloys used in compact heat exchangers (listed in Table 3), big differences can be found. As show in Figure 1, the most significant difference between polymer and metal materials is the thermal conductivity. The thermal conductivities of most polymers listed are lower than 1W/mK, which are around 100 times lower than those of most metals. Because of this, it might appear futile to pursue polymers for heat transfer application. However, if we consider the application of heat exchangers with corrosive fluids, seawater in particular, the only possible metals will be Cu-Ni alloys and Titanium. Cu-Ni alloys offer good resistance to corrosion, polluted water, and deposit attack, but can be expensive. Recent advances in manufacturing technologies now permit the use of titanium, which is highly resistant to corrosion and provides more flexibility in the design of heat exchangers due to its low density and high strength. However, as shown in Table 3, corrosion resistant materials such as Cu-Ni alloys and titanium have low thermal conductivities compared to copper and aluminium, (17 to 50W/m K). To overcome this, the conductive thermal resistance of these materials is generally lowered by decreasing the thickness of the heat exchanger wall 8 .
The application of air in micro-bubbles DR is environmentally friendly and cheaper compared to polymers and surfactants [77–78]. Micro-bubbles have diameters less than ten-microns and exhibit behaviours different from those of larger size bubbles. These differences are seen in their chemical and physical characteristics such as the tendency to be suspended in the liquid phase over a longer time . The first work published on the application of micro-bubbles as DRAs was by . The mechanism of DR by micro-bubbles is not yet well understood. Similar to other DR techniques, the essence of micro-bubble injection is to change the boundary layer structure. It had been suggested that micro-bubbles reduce drag by altering both laminar and turbulent boundary-layer characteristics . It has been reported that, injecting air bubbles increases kinematic viscosity and decreases turbulent Reynolds number in the buffer layer . This results in enlarging the viscous sub-layer thereby decreasing the velocity gradient at the wall.  used particle image velocimetry (PIV) to investigate the effect of injecting low void fraction micro-bubbles into the boundary layer of a channel flow. Some of their results showed some similarities with drag reduction behaviour by polymers or surfactants as well as reports of some earlier investigations [80–81]. These similarities include thickening of the buffer layer as well as upward shift of the log-law region. They stated that the micro- bubble layer formed at the top of the channel was not responsible for the drag reduction recorded. This micro-bubble layer served to reduce the slip between the micro-bubbles and the liquid. The major contribution to drag reduction is the accumulation of micro-bubbles in a critical zone within the buffer layer. The interaction of micro-bubbles with turbulence in the buffer layer is responsible for the observed DR. in general, injection of micro bubbles reduces turbulent energies with the shear in the boundary layer remaining unchanged . There appears to be some agreement on the mechanism of micro-bubble drag reduction especially as it relates to thickening of the viscous sub- layer and turbulence suppression.
Lowpermeability soil was collected from the Hawks bay beach in Karachi. The soil sample was classified as sandy soil (97.6% sand, 2% silt and 0.4% clay) by the Unified Classification System procedure (based on ASTM D-2487) with 6.17% of organic matter (OM) and a cation exchange capacity (CEC) of 25.2 mmol/kg. The soil was passed through a 2 mm sieve to remove stones, branches and any other coarse material. The soil sample was then washed with distilled water followed by 2% commercial sulphuric acid (Merck, Pakistan) to remove organic components from the soil. Rinsing with distilled water was repeated. Properties of the soil such as pH and moisture content were determined in the laboratory using standard methods . An initial concentration of 200 mg/kg of nickel was detected in the soil sample, which was beyond the limits specified by Yawar et al. . Hydraulic conductivity of the soil was measured in the laboratory as reported in the literature  and was found to be in the range of 10 -10 to 10 -9 m/s. Initial pH of the soil was 5.5 as shown in Table 2.
of back muscle activity in LBP patients differed from healthy controls. Particularly, a 9 × 7 (63)-channel LA-SEMG system (62 electrodes plus one common ground located at the center of the pad) measuring 25 cm tall by 19 cm wide was attached to the low back region bilaterally. Two-dimensional muscle activity scans (root mean square [RMS] value of the voltage over 1 s) were taken during three tasks, including upright stand- ing, trunk forward flexion in 20°, and standing while holding a 3-pound dumbbell in each hand. Two reviewers, blinded to group status, qualitatively described the visual characteristics of each scan. The study team recruited 13 participants with acute LBP, 25 participants with chronic LBP, and 163 pain- free controls. Additionally, participants with acute LBP were followed up for up to 6 weeks. In the pain-free population, > 90% participants demonstrated balanced regional muscle activity patterns (nominally identified as diamond, Vee, and columnar) symmetrically over both sides of the spine. In addi- tion, higher muscle activity was observed in muscles located closer to the spinal column and from L3 to S1. In contrast, participants with acute LBP demonstrated increased muscle activity asymmetrically on the painful side, or multifocal, also with higher RMS values on the painful side. Participants with
The extent of gastro-intestinal absorption is one of the key properties for drugs intended for oral administration [1-6]. Of many factors that govern intestinal absorption of a compound, permeability is often tested in vitro by means of cell-based assays such as the Caco-2 assay [2- 8]. While the Caco-2 assay is the gold standard for in vitro permeability assessment, interpretation of the results from such assays needs careful attention due to high lab-to-lab variability [6, 8].
The diversification of macro-organisms over the last 500 million years often coincided with the development of new environmental niches. Microbial diversification over the last 4 billion years likely followed similar patterns. However, linkages between environmental settings and microbial ecology have so far not been described from the ancient rock record. In this study we investigated carbon, nitrogen and molybdenum isotopes and iron speciation in five non-marine stratigraphic units of the Neoarchean Fortescue Group, Western Australia, that are similar in age (2.78-2.72 Ga) but differ in their hydro-geologic setting. Our data suggest that the felsic-dominated and hydrologically open lakes of the Bellary and Hardey formations were probably dominated by methanogenesis (δ 13 C
The literatures studied establish the possibility of utilizing solid waste materials like, plastic, wood, metal, paper, glass and demolished concrete as constituent of building materials. The use of these wastes at adequate level of replacement or proportions as the case may be, will improve the intrinsic properties of the building materials concerned. The application of these construction materials in real construction is limited. More research is needed to study the actual behaviour or performance of solid waste-based building materials in their practical applications because, properties like durability which has to do with long-term performance can be best studied through this means. In addition, the need to establish an energy efficient method for processing the solid waste to make them suitable for use in concrete standard mix design formulation is also required.
Perspectives of discovering unconventional hydrocarbon resources are associated with the development areas of immature «rich» and «very rich» potential oil source shaly low-permeability rocks at the initial stage of the «oil window» or at the approach to it in the source beds containing rich but relatively immature organic matter. At that, the major criterion for the exploration for shale hydrocarbons are not traps where hydrocarbons accumulate and accumulations form but directly the rock volumes where hydrocarbons were generated but did not emigrate from them. The recoverable hydrocarbons will be contained in a bed at concentration, which emerged as a result of their generation in situ. Targets of the forecast and exploration should be oil and gas plays.
five load steps, applied using a stress increment ratio of unity, and covering the stress range of 12.5 to 200 kPa. two-way drainage was allowed via porous discs in contact with the top and bottom ends of the test specimens. The coefficient of permeability values in the vertical and horizontal directions were measured directly during the pause stages of consolidation tests conducted in the hydraulic consolidation (Rowe cell) apparatus. These specimens were allowed to drain to atmosphere under stresses of 20, 30 and 40 kPa (applied across the cell diaphragm) over a period of 24 h. The constant head permeability tests were each of 8 h duration and were conducted at the end of each load step. The first 6 h period of the permeability test allowed for steady flow conditions to become established under the constant head of 1.15 m applied. The quantity of flow over the following 2 h period was then measured by recording the mass of the effluent water collected in a graduated cylinder.
Therefore, we want to study the variation of the SPC with micro-structure parameters and elastic moduli of rocks when taking into account the effects of the difference in the zeta potential between samples for a set of Berea sandstone that has not yet studied. To do so, the ratio of the SPC and zeta potential is used rather than the SPC only. The results have shown that the SPC strongly depends on the permeability and the porosity of the samples for low fluid electrical conductivity. However, when the fluid conductivity is larger than a certain value that is determined by the mineral compositions of the sample, the SPC is completely independent of permeability. The results also show that there is no clear correlation between the SPC and porosity, grain density, tortuosity, formation factor, bulk modulus and or shear modulus of rocks.
(2) Vitrinite reflectance: 1. 50 points of measurement were assessed to obtain the vitrinite reflectance measurement of the Jiao-Zuo coal sample and the Fu-Xin coal sample and the average Ro% values were respectively 3.43 and 0.61 (Fig. 16). 2. According to the original mixing proportion, as determined by the pyrolysis analysis and using random sampling, 50 measured points respectively that complied with the proportion were taken and then averaged. Each sample with mixing proportion was taken in this manner for 1000 times and then the average was calculated as the vitrinite reflectance results after proportional mixing. The results for mixed samples are as follows (Fig. 17): Sample no. 2 (mixed sample)had an Ro% of 3.32; sample no. 3 (mixed sample) had an Ro% of 3.15; sample no.4 (mixed sample) had an Ro% of 2.87; sample no. 5 (mixed sample) had an Ro% of 2.59. Besides, each Ro% value of randomly mixed proportion was stable. As the vitrinite reflectance measured point of low maturity increased, the vitrinite reflectance results of mixed samples showed a linear decline. Not quite unexpectedly one obtains a approximate "mixing line" for the Vitrinite Reflectance values : Ro% (xH)= xH*3.5 + (1-xH)*0.6in the figure 17 (xH : the mixing proportion of high maturity Jiao-Zuo original coal sample). Nevertheless, several mixed samples continued to show high maturity characteristics. 3. The vitrinite reflectance results of the original samples and mixed samples, as well as the corresponding Tmax values, were placed on a plot of good correlation (Lang Dongsheng et al, 1999). The results display that in more extreme cases (mixed samples comprising of substrates with highly different maturities), the relationship of mixed samples deviates from the general linear trajectory (Fig. 18). This suggests that when extracting strata samples that contain reworked sedimentary materials, the Tmax measurement of the sample is likely to reflect the maturity of the younger materials present.
In terms of the composition of hydrocarbon components of bitumoid and products of desulfurization of its polar fraction, the main bio-producers that contributed to the composition of OM of Jurassic deposits are marine phytoplankton and, to a lesser extent, Embryophytes. One of the main differences in the composition of pyrolysis products of kerogens isolated from rocks comprising various concentrations of total organic carbon (TOC) is the increasing proportion of thiophenic structures as TOC increases. The presence of low-molecular or short-chain alkyl-substituted thiophenes with a linear carbon skeleton in pyrolysis products is due to the involvement of carbohydrate components of the starting organic matter in the processes of sulfur bonding in the stages of sedimentogenesis and diagenesis. Sulfurization of carbohydrates resulted in the formation of a poly-sulfur-bound structure that is part of kerogen, which, when pyrolyzed, yields thiophenes of similar structure. There was an increase in the content of long-chain n-alkylthiophenes in the higher-molecular fraction.
The Court has a wide margin of manoeuvre in its application of the Priority Policy, which can sensibly influence the volume of pending applications and the ratio of the various categories within them. For example, in 2011 fewer judgments were deliv- ered, but the focus was given to the top three categories, which was quite the opposite of what happened in 2013. In 2014, there was again an increase in dealing with the top three categories. The outcome of the implementation of the priority policy has to be read in conjunction with the introduction of new formations. While they seem to have different scope, these two reforms in fact complete each other. With the introduction of the single judge formation and the new competences of the three judges committees, judges have more time to dedicate to more serious issues. In 2014, almost half of the high priority (Category I to III) applications originated from two States: Russia and Romania, Turkey being third on this unflattering podium. Also, almost half of the cases are part of the “Brighton backlog” which, despite the increase in by 30 of the number of cases disposed of in 2014, has increased by 16%. In 2015, 35% of the top three category cases were to be considered as “Brighton backlog”. These cases take precedence over all others and more resources are dedicated to them.
Scaffold provides adequate signals (e.g., through the use of adhesion peptides and growth factors) to the cells, to induce and maintain them in their desired differentiation stage and for their survival and growth Thus, equal effort should be made in developing strategies on how to incorporate adhesion peptides and growth factors into the scaffolds to influence cell behaviour, and to establish the concentrations and distributions required for successful outcomes. Additionally, the incorporation of drugs (i.e., inflammatory inhibitors and/or antibiotics), into scaffolds may be used to prevent infection after surgery. The field of biomaterials has played a crucial role in the development of tissue engineered products. An alternative to using prefabricated scaffolds is to use a polymer system that is injected directly into the defect site which is polymerised in situ using either heat , thermo responsive polymers, or light (photo responsive polymers). The advantages for the patient with this approach are that injectable delivery systems fill both regularly and irregularly shaped defects, and so “get a custom fit”, they represent a minimally invasive procedure therefore avoiding surgery and its potential risks, eliminate the need for donor tissue or a donor site, and waiting time for treatment is reduced. At present, there is a vast amount of research being performed on all aspects of tissue
The model established consider all the variables in the system that influence the transport of water in concrete structure, initially, concrete attained strength by curing the structure component, but when it has attained the required strength, the fluid passing through the macropores established is through the influence of permeability, this will decrease the structural compressive strength, water transport on the structure are caused by the variables on the model developed. Applying the mathematical expression will definitely monitor the rate of water migrating on concrete structure, the variable that allows the water transport has been expressed. The permeability influence that relate with the macropores between the constituent of the concrete is the mixture of fine. Sand, cement, water and coarse aggregate, including the mixture and compressibility of concrete placement through compaction are expressed base on various rates. The model can be simulated to develop the theoretical values that can be compared with the experimental values for validation of permeability coefficient in concrete structure.