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The emergency conservation of historical objects is necessary because several instances in which paintings and records were flooded owing to unusual weather conditions have recently been reported. Early action is especially important in preventing biodeterioration in case of flood damage. In this study, the feasibility of using gamma rays as a biological control method was assessed. Material stability was evaluated by applying different irradiation doses to natural dyes used in historical paintings and costumes. Sappan wood, gardenia fruit, and indigo were selected and prepared as natural dye samples using standard colorant materials. The fading behavior of the samples was analyzed by measuring their CIE L*a*b* color space values, and UV-Vis spectroscopy and liquid chromatography tandem mass spectrometry (LC-MS) were used to obtain their spectra. We confirmed that the dyes began to decompose upon exposure to gamma rays at a dose of 10 kGy. Irradiation at a dose of 50 kGy led to the complete decomposition of the chromophoric groups because the dye components could not be detected by LC-MS. Therefore, studying the influence of low-dose gamma-ray irradiation is necessary to preserve dye colorants. The data obtained in this study can be used as a foundation for further research on the influence of gamma rays on historical objects.

We investigated the properties of Korean traditional animal glue which are associated with the use of different parts of cattle hide and extraction conditions. Both average molecular weight(Mw, Mz) and polydispersity (PDI) of the animal glue increased with extraction time, whereas only PDI decreased after 48h. There were no differences in the average molecular weight and PDI for the different cattle hide parts used, although a individual difference was observed with regard to total molecular weight. Differences in extracts over time were compared by investigating the amide regions representing the gelatien component of the animal glue. The triple helix structure of the belly skin deteriorated in a manner proportional to the extraction time, and differences were observed for each cattle hide part. The yellowness increased with the extraction time; however, the viscosity was not proportional to the average change in molecular weight. This study has some limitations because of difficulties in the quality control of cases where small amounts of glue were extracted as small differences might impact the overall results considerably. Further research exploring various extraction conditions is required to ensure the prodiction of traditional animal glue with optimum qualities.

It has been recognized that an integration of neuronal and genetic mechanisms supports brain function, regulates behaviour, and underpins response to environmental or disease stimuli. Several different technologies are available for imaging and studying neuronal activity in living brains, such as functional magnetic resonance imaging (fMRI), and have been translated to humans. However, the tools available to measure gene expression are destructive. Here we present a method, called epigenetic MRI (eMRI), that overcomes this limitation. eMRI achieves for the first time direct and noninvasive imaging of DNA methylation, a major gene expression regulator, in intact brains. eMRI exploits the methionine metabolic pathways that are responsible for DNA methylation to label the methyl-cytosine in brain genomic DNA through carbon-13 enriched diets. It then uses a novel carbon-13 magnetic resonance spectroscopic imaging (13C-MRSI) method to map the spatial distribution of labeled DNA. We demonstrated successful 13C labeling of brain DNA through diet using mass spectrometry, and robust and specific detection of labeled DNA using 13C-MRSI. We used eMRI and a biomedical piglet model to produce the first DNA methylation map of an intact brain hemisphere. With both noninvasive labeling and imaging, we expect eMRI to be readily translated to humans and thus enable many new investigations into the epigenetic basis of brain function, behavior, and disease.

A major challenge to experimental studies and therapeutic uses of hematopoietic stem cells (HSC) is the limited options for analytical tools that can reliably resolve functional differences in heterogeneous HSC subpopulations at the single cell level. Currently available methods require the use of external labels and/or separate clonogenic and transplantation assays to identify bona fide stem cells, necessitating the harvest of bulk cell populations and long incubation times that obscure how individual HSCs dynamically respond to exogenous and endogenous stimuli. In this study, we employ Raman spectroscopy to noninvasively resolve the dynamics of individual differentiating hematopoietic progenitor cells during the course of neutrophilic differentiation. We collected Raman peaks of individual cells daily over the course of 14-day neutrophilic differentiation. Principal component analysis (PCA) of the Raman peaks revealed spectral differences between individual cells during differentiation that were strongly correlated with changes in the nucleus shape and surface antigen expression, the primary traditional means of monitoring neutrophilic differentiation. Additionally, our results were consistently reproducible in independent rounds of neutrophilic differentiation, as demonstrated by our partial least-squares discriminant analysis (PLS-DA) of the Raman spectral information that predicted the degree of neutrophilic differentiation with high sensitivity and specificity. Our findings highlight the utility and reliability of Raman spectroscopy as a robust molecular imaging tool to monitor the kinetics of HSC differentiation patterns.

The rheological properties of reactive materials are of importance in industrial or academic purpose. However, it is hard to characterize these properties for overall range of reaction, because curing reaction accompanies enormous and intricate structural changes. Consequently, it is demanded to establish the model which elucidates the rheological changes as a function of degree of reaction. In this study, we observed the curing behavior of novolac epoxy/phenol novolac/triphenylphosphane (TPP) system in stoichiometrically balanced state. We developed a new empirical model describing the change of rheological profile of epoxy system for the wider range of degree of reaction, α. Newly suggested empirical equation as a function of α is applied to analyze the evolution of rheological variables during polymerization of polymethyl methacrylate. It is shown that the new empirical model is suitable to analyze the viscosity profile for systems including reactions such as curing or polymerization.

Adhesion is a critical cellular process that contributes to migration, apoptosis, differentiation, and division. It is followed by the redistribution of cellular materials at the cell membrane or at the cell-surface interface for cells interacting with surfaces, such as basement membranes. Dynamic and quantitative tracking of changes in cell adhesion mass redistribution is challenging because cells are rapidly moving, inhomogeneous, and nonequilibrium objects, whose physical and mechanical properties are difficult to measure or predict. Here, we report a novel biosensor based microscopy approach termed Photonic Crystal Enhanced Microscopy (PCEM) that enables the movement of cellular materials at the plasma membrane of individual live cells to be dynamically monitored and quantitatively imaged. PCEM utilizes a photonic crystal biosensor surface, which can be coated with arbitrary extracellular matrix materials to facilitate cellular interactions, within a modified brightfield microscope with a low intensity non-coherent light source. Benefiting from the high sensitivity, narrow resonance peak, and tight spatial confinement of the evanescent field atop the photonic crystal biosensor, PCEM enables label-free live cell imaging with high sensitivity and high lateral and axial spatial-resolution, thereby allowing dynamic adhesion phenotyping of single cells without the use of fluorescent tags or stains. We apply PCEM to investigate adhesion and the early stage migration of different types of stem cells and cancer cells. By applying image processing algorithms to analyze the complex spatiotemporal information generated by PCEM, we offer insight into how the plasma membrane of anchorage dependent cells is dynamically organized during cell adhesion. The imaging and analysis results presented here provide a new tool for biologists to gain a deeper understanding of the fundamental mechanisms involved with cell adhesion and concurrent or subsequent migration events.

In our body, stem cells reside in a microenvironment termed the niche. While the exact composition and therefore the level of complexity of a stem cell niche can vary significantly tissue-to-tissue, the stem cell niche microenvironment is dynamic, typically containing spatial and temporal variations in both cellular, extracellular matrix, and biomolecular components. This complex flow of secreted or bound biomolecules, cytokines, extracellular matrix components, and cellular constituents all contribute to the regulation of stem cell fate specification events, making engineering approaches at the nano- and micro-scale of particular interest for creating an artificial niche environment in vitro. Recent advances in fabrication approaches have enabled biomedical researchers to capture and recreate the complexity of stem cell niche microenvironments in vitro. Such engineered platforms show promise as a means to enhance our understanding of the mechanisms underlying niche-mediated stem cell regulation as well as offer opportunities to precisely control stem cell expansion and differentiation events for clinical applications. While these principles generally apply to all adult stem cells and niches, in this review, we focus on recent developments in engineering synthetic niche microenvironments for one of the best-characterized stem cell populations, hematopoietic stem cells (HSC). Specifically, we highlight recent advances in platforms designed to facilitate the extrinsic control of HSC fate decisions.

Until now most of the leadership studies have been focused to managers having in formal authority. However, in the recent business environment, team member should also demonstrate his leadership. Hence, the purpose of this study has been focused to the team member`s leadership and their leadership effectiveness. In this study, we verified how the degree of master sergeant`s support can control to moderate the intensity of the team member`s leadership behavior. The analysis results were as follows: we have found that team member`s issue leadership can effect on positive(+) way on the audience`s acceptance to the leader as well as team performance. But the moderating effects of master sergeant`s support on the team member`s issue leadership and leader acceptance was not significant in terms of statistical point of view. It has also shown even the negative(-) effects of master sergeants`s support on the team member`s issue leadership and leader acceptance as well as team performance. Through this study, we can understand that the master sergeant`s support may impeding the team member`s independent leadership.

Microfiltration (MF) processes are used in a variety of separation and concentration applications. Since membrane fouling is inevitable, membranes must be regularly cleaned to remove both organic and inorganic material deposited on the surface and/or into the membrane bulk. Optimization of the cleaning conditions for MF membranes is especially important. If the dose of cleaning chemical or cleaning time is inadequate, the membrane permeability is not recovered. If a dose of the chemical or the time is excess, irreversible damages in membrane properties occur. However, it is difficult to find the optimum conditions for chemical cleaning of MF. In this study, response surface methodology (RSM), a facile tool for optimization, was employed to determine the optimum conditions for chemical cleaning of MF. The Box–Behnken center-united experimental design was used to quantify the effects of respective chemicals (citric acid and sodium hypochlorite) dose and treatment time on fouling control and organic ...

According to the recent community-based structures enlargement, specification, and diversification. It needs appropriate construction materials in terms of intensity and environmental aspects. Thus, in manufacturing the cement using micro limestone powder that is main material. It is also expected to save energies and reduces CO2, by using the blast furnace slag and fly ash which are mitigated environmental load construction materials that emerged. In this research, the durability aspect tries to be grasped considering the chemical property according to the coherence of the hydration product. Consequently, the compressive strength was measured over 30Mpa on 3rd. In addition, according to the content of the limestone powder, the setting time is promoted. It has the feature expanded in the length change. And it is determined because the possibility of replacing the existing for construction material such as it is measured compared with the time to use the portland cement usually that flexural strength is high with the age 7 days ago, so it is sufficient.

This research is to observe the shoreline changes in Jinha beach over the 50 years with aerial photographs and satellite images. The shoreline image feature was retrieved from the corrected images using wet and dry techniques and analyzed by DSAS from the statistical point of view. From 1967 to 1992, the mouth of Hoeya River was severely blocked and the northern shoreline off Jinha beach was eroded. The blockade of river mouth seemed to have been eased along with the completion of the dike, but soil continued to be deposited along the high sea away from the river month. Compared to the past, a layer of sediment has been formed off the northern coastline while the southern coastline has eroded. At least in the region subject to this research, the construction of a training dike is to blame. On top of that, a mere combination of dredges and artificial nourishment is not enough to take under control the changing shorelines properly. Thus, it is necessary to devise a more fundamental solution by taking into account reasons behind sediment from the river area that could change the shorelines besides the costal environment.

Roads play a crucial role in societal infrastructure as a main artery for the economy and lives of people. However, numerous deformations are caused by an increasing number of overloaded vehicles. Accordingly, an efficient managing system for preventing overloaded vehicles could be organised by using the road as a scale by applying a genetic algorithm to analyse the load and drive information of vehicles. First, accurate analysis of loads by using the behaviour of the road itself is needed to solve illegal axle manipulation problems of overloaded vehicles and to install intelligent embedded load analysis systems. Accordingly, to use the road behaviour, the transformation in this way was measured by installing an underground box-type indoor model, and an indoor experiment was conducted by using a genetic algorithm. After five driving sessions with each vehicle, 50 sets of dynamic responding data were attained. The recognition variables were calculated to be within the error range of 10%.

We demonstrate photonic crystal enhanced fluorescence (PCEF) microscopy as a surface-specific fluorescence imaging technique to study the adhesion of live cells by visualizing variations in cell-substrate gap distance. This approach utilizes a photonic crystal surface incorporated into a standard microscope slide as the substrate for cell adhesion, and a microscope integrated with a custom illumination source as the detection instrument. When illuminated with a monochromatic light source, angle-specific optical resonances supported by the photonic crystal enable efficient excitation of surface-confined and amplified electromagnetic fields when excited at an on-resonance condition, while no field enhancement occurs when the same photonic crystal is illuminated in an off-resonance state. By mapping the fluorescence enhancement factor for fluorophore-tagged cellular components between on- and off-resonance states and comparing the results to numerical calculations, the vertical distance of labelled cellular components from the photonic crystal substrate can be estimated, providing critical and quantitative information regarding the spatial distribution of the specific components of cells attaching to a surface. As an initial demonstration of the concept, 3T3 fibroblast cells were grown on fibronectin-coated photonic crystals with fluorophore-labelled plasma membrane or nucleus. We demonstrate that PCEF microscopy is capable of providing information about the spatial distribution of cell-surface interactions at the single-cell level that is not available from other existing forms of microscopy, and that the approach is amenable to large fields of view, without the need for coupling prisms, coupling fluids, or special microscope objectives.

According to the recent community-based structures enlargement, specification, and diversification. It needs appropriate construction materials in terms of intensity and environmental aspects. Thus, in manufacturing the cement using micro limestone powder which is main material. It is also expected to save energies and reduces , by using the blast furnace slag and fly ash which are mitigated environmental load construction materials that emerged. In this research, The durability aspect tries to be grasped considering the chemical property according to the coherence of the hydration product. Consequently, The compressive strength was measured over 30 Mpa on 3rd. In addition, according to the content of the limestone powder, the setting time is promoted. It has the feature expanded in the length change. And it is determined because the possibility of replacing the existing for construction material such as it is measured compared with the time to use the portland cement usually that flexural strength is high with the age 7 days ago, so it is sufficient.

In this study, a new type of thiophene-based polybenzimidazole was synthesized by the condensation polymerization of 2,5-thiophene dicarboxylic acid and 3,3′-diaminobenzidine for high-temperature proton exchange membrane fuel cells. The resulting poly(benzimidazole-co-thiophene) (PBITH) membrane was prepared using the direct casting method at 200 °C in a hot press. The PBITH membranes were immersed in a 10 mol phosphoric acid (PA) solution for 2 weeks. The proton conductivity of the doped-PBITH (DPBITH) membrane increased with increasing temperature, and the maximum conductivity was 0.120 S cm−1 at 150 °C and 15 % relative humidity. The DPBITH showed higher proton conductivity than the doped-polybenzimidazole membrane due to the presence of additional thiophene heterocycles. Incorporation of the thiophene groups as an additional sulfur containing heterocycle increased the basicity of the polymer backbone and enhanced the interaction between PA and the polymer. A novel thiophene-based polybenzimidazole membrane was synthesized through the condensation polymerization of 2,5-thiophene dicarboxylic acid and 3,3′-diaminobenzidine in phosphorous pentoxide/methanesulfonic acid solvent medium. The proton conductivity of the phosphoric acid–doped membrane was found to be 0.120 S cm−1 at 150 °C and 15 % relative humidity.

Primary murine HSCs show divergent fate decisions with biomaterial engagement and due to marrow-inspired biophysical cues., Hematopoiesis is the physiological process where hematopoietic stem cells (HSCs) continuously generate the body’s complement of blood and immune cells within unique regions of the bone marrow termed niches. Although previous investigations have revealed gradients in cellular and extracellular matrix (ECM) content across the marrow, and matrix elasticity and ligand type are believed to be strong regulators of stem cell fate, the impact of biophysical signals on HSC response is poorly understood. Using marrow-inspired ECM ligand–coated polyacrylamide substrates that present defined stiffness and matrix ligand cues, we demonstrate that the interplay between integrin engagement and myosin II activation processes affects the morphology, proliferation, and myeloid lineage specification of primary murine HSCs within 24 hours ex vivo. Notably, the impact of discrete biophysical signals on HSC fate decisions appears to be correlated to known microenvironmental transitions across the marrow. The combination of fibronectin and marrow matrix-associated stiffness was sufficient to maintain hematopoietic progenitor populations, whereas collagen and laminin enhanced proliferation and myeloid differentiation, respectively. Inhibiting myosin II–mediated contraction or adhesion to fibronectin via specific integrins (α5β1 and ανβ3) selectively abrogated the impact of the matrix environment on HSC fate decisions. Together, these findings indicate that adhesive interactions and matrix biophysical properties are critical design considerations in the development of biomaterials to direct HSC behavior in vitro.

In this chapter, we describe recent advances in the noninvasive optical imaging of stem cells using photonic crystal label-free biosensor surfaces. Technological progress in bioengineering approaches now enables the sophisticated control of live cells in vitro. In such applications, stem cells are often selected as the cell source, as they have the capacity to expand to provide a large pool of cells with varying levels of self-renewal and differentiation potential (stem cells, progenitor cells, terminally differentiated cells) necessary to meet desired therapeutic goals. Precisely engineering stem cell fate decisions, however, has remained a challenge due to the lack of analytical tools that allow dynamic monitoring of heterogeneous stem cell populations in situ in real time at the single-cell level. Currently available technologies such as fluorescence labeling or clonal expansion assays are almost always end-point analyses of ensemble populations of cells that are expensive, labor intensive, and time delayed. New optical imaging tools may increasingly permit label-free imaging of live cells for subcellular-resolution quantification of cellular activities in real time. Noninvasive optical imaging using a nanostructured photonic crystal surface in place of an ordinary glass or plastic substrate for cell growth can be easily integrated into existing bioengineering platforms such as microfluidics or microarrays and can provide a novel, alternative approach to monitor single stem cell activities in vitro. Here, we first detail the principles of photonic crystal enhanced microscopy (PCEM) then offer a detailed rationale for developing new tools that enable monitoring and screening of increasingly small populations of stem cells in vitro. Finally, we close by describing efforts to apply PCEM to characterize stem cell differentiation events via adhesion-based metrics of stem cell differentiation.

The cement industry consumes large amounts of energy and uses limestone as a main raw material. The associated CO 2 emissions are a main target of efforts to combat global warming and other environmental problems. With the advent of cutting-edge technology and increased public awareness of global environmental issues, the cement industry is actively seeking ways to diversify resources. This study was designed to assess the material properties of zeolite cement mortar that primarily consists of natural zeolite, which has recently drawn attention as an alternative cement material. We address strength properties and optimal mix proportions using an alkali activator (NaOH) instead of water (H 2 O) for preparing hardened zeolite mortar samples through alkali-activated reactions. The 7-day compressive strength of natural zeolite cement mortar was 43.5 MPa when optimal proportions of the alkali activator and curing temperature were applied. In the results of this study, zeolite cement has greater strength than existing normal Portland cement and has great potential to replace current construction materials.

The ability to self-renew and differentiate into multiple types of blood and immune cells renders hematopoietic stem and progenitor cells (HSPCs) valuable for clinical treatment of hematopoietic pathologies and as models of stem cell differentiation for tissue engineering applications. To study directed hematopoietic stem cell (HSC) differentiation and identify the conditions that recreate the native bone marrow environment, combinatorial biomaterials that exhibit lateral variations in chemical and mechanical properties are employed. New experimental approaches are needed to facilitate correlating cell differentiation stage with location in the culture system. We demonstrate that multivariate analysis of time-of-flight secondary ion mass spectrometry (TOF-SIMS) data can be used to identify the differentiation state of individual hematopoietic cells (HCs) isolated from mouse bone marrow. Here, we identify primary HCs from three distinct stages of B cell lymphopoiesis at the single cell level: HSPCs, common lymphoid progenitors, and mature B cells. The differentiation state of individual HCs in a test set could be identified with a partial least-squares discriminant analysis (PLS-DA) model that was constructed with calibration spectra from HCs of known differentiation status. The lowest error of identification was obtained when the intrapopulation spectral variation between the cells in the calibration and test sets was minimized. This approach complements the traditional methods that are used to identify HC differentiation stage. Further, the ability to gather mass spectrometry data from single HSCs cultured on graded biomaterial substrates may provide significant new insight into how HSPCs respond to extrinsic cues as well as the molecular changes that occur during cell differentiation.

>> Phosphoric acid-doped poly (2,5-benzimidazole) (DABPBI) was prepared by condensation polymerization of 3,4-diaminobenzoic acid for high temperature proton electrolyte membrane fuel cells. The membranes were casted directly using a hot-press unit and characterized by fourier transform infrared spectroscopy, thermogravimetric analysis, conductivity measurement, scanning electron microscopy and tensile test. The proton conductivities of DABPBI are observed to be 0.062 and 0.018 S·cm -1 under 30 and 1% relative humidity, respectively at a temperature of 120 o C whichis appreciably higher than that of Nafion 115 under similar conditions. The DABPBI membrane has demonstrated excellentthermo- mechanical properties and proton conductivity suggesting its suitability as a high temperature membrane. Key words : Poly(2,5-benzimidazole)(폴리(2,5-벤지이미다졸)), Membrane(전해질막), High temperature proton electrolyte membrane fuel cells(고온용 고분자 전해질 막 연료전지), Mechanical property(기계적 특성),Proton conductivity(수소 이온 전도도)

Differential Power Analysis is fully affected by various noises including temporal misalignment. Recently, Ryoo et al have introduced an efficient preprocessor method leading to improvements in DPA by removing the noise signals. This paper experimentally proves that the existing preprocessor method is not applied to all processor. To overcome this defect, we propose a Differential Trace Model(DTM). Also, we theoretically prove and experimentally confirm that the proposed DTM suites DPA.

This paper investigates the possibilities of protecting game developers under the work-for-hire provision of copyright law. Fundamentally, the work-for-hire clause provides the authorship status to companies, not to game developers. Some argue that the clause is especially appropriate in software industries including game industries because they are new and different from typical types of copyright industries. However, game industries are different from software industries as well as typical types of copyright industries in that they have both cultural (artistic) as well as industrial characteristics. Game developers not being provided with the authorship status may be one of the reasons for the disputes related to turnover and knowledge leakage. This paper mainly suggests three kinds of solutions: first, protecting the moral right even in the work-for-hire provision; second, protecting game developers as coauthorship; and third, providing monetary compensation as it is in employee invention.

Background Although seasonal affective disorder and premenstrual syndrome (PMS) are frequently observed in mood disorders, little is known as to whether lifetime traits of seasonality and premenstrual distress are related to bipolar disorder independent of mood episodes. This study aimed at investigating these two cyclic traits with respect to bipolar I and II disorders as well as evaluating the association between them. Methods Subjects included 61 female patients with bipolar I or II disorders and 122 healthy women. Seasonality and premenstrual symptoms were measured retrospectively on a lifetime basis using the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Premenstrual Symptoms Screening Tool (PSST). Results Patients showed higher global seasonality scores on the SPAQ compared to the normal controls. Further, the patient-control difference was more prominent in cases of bipolar II disorder ( p p = 0.001). The prevalence of moderate to severe PMS as indicated on the PSST was also signifcantly higher in bipolar II disorder patients (51.6%) as compared to controls (19.7%). A significant association between seasonality and PMS was observed in both patient and control groups. Conclusions The results suggested that female patients with bipolar disorder experience seasonal and premenstrual changes in mood and behavior regardless of their mood episodes, and traits of seasonality and PMS are associated with each other. A common biological mechanism of these two cyclic conditions may be involved in the development of the cyclicity of bipolar disorder.

The protective antigen (PA) of Bacillus anthracis is a secreted protein that functions as a critical virulence factor. Protective antigen has been selected as a biomarker in detecting bacterial infection. The in vitro selection method, systematic evolution of ligands by exponential enrichment (SELEX), was used to find single-stranded DNAs that were tightly bound to PA. After 8 rounds of the SELEX process with PA, 4 different oligonucleotides (referred to as aptamers) that contain a 30-residue ssDNA sequence were identified. Dissociation constant (K(d)) values with Cy3-attached aptamers were determined via fluorophotometry to be within a nanomolar range. The authors attempted to visualize the detection of PA using an aptamer-based enzyme-linked immunosorbent assay method, which has proven to be successful within a nanomolar K(d) value range. Furthermore, 2 of the 4 aptamers exhibited specificity to PA against bovine serum albumin and bovine serum. The results of this study demonstrate the analytical potential of an oligonucleotide-based biosensor for a wide variety of applications, particularly in diagnosing disease through specific protein biomarkers.

Cement is becoming a principal factor in air pollution because of the creation of CO2 during its manufacturing. The exhaustion of the natural resources needed for Portland cement production is also an issue. Therefore, a substitute material for this type of cement is needed. Nano-scale materials are of great interest due to their unique optical, electrical, and magnetic properties. These properties are strongly dependent on the sizes and shapes of the particles, and, therefore, it is important to be able to develop the construction part which retains the excellent properties of the nano-sized material. The purpose of this study was to synthesize nano-powder as a substitute for cement using a chemical method. This study investigated the compressive strengths of concretes with various compositions. Specimens were tested for compressive strength three, seven, 14, and 28 days after manufacture. In the results of this study, the medium-sized (50% by weight) nano-cement particles created via chemical synthesis were less than 168 nm in size, and the compressive strength of the mortar prepared using these nanoparticles was 53.9 MPa

In South Korea, as the living standard has been getting higher, meat consumption is steadily increasing. To meet the country's demand, livestock houses become larger and wider with increased raising density. In larger livestock houses, pollutants such as flake of pig skin, excrement, odor, various dusts and noxious gas like ammonia are excessively accumulated inside the facility. These will cause weak immunity for the pigs, diminution of productivity and degeneration of working condition. These problems can be solved through the ventilation performance of the facility. In the winter time, ventilation must be controlled to minimum to maintain a suitable thermal condition. However, this affects the other internal environmental condition because of the minimum ventilation. The installation of “wet air cleaner” especially in the winter time can be an alternative solution. For efficient application of this machine, there is a need to understand the existing ventilation condition and analyze the interaction of existing ventilation system with the wet air cleaner considering its appropriate location. In this study, the existing ventilation system as well as the internal environmental condition negatively inside the facility with the wet air cleaner has been studied using CFD technology. The CFD simulation model was validated from the study conducted by Seo et al. (2008). Results show that the elimination rate of ammonia was 39.4 % and stability could be improved to 35.1 % (Comparing case 5 to 1 where wet air cleaner machine was not used). It can therefore be concluded that case 5 shows the optimum location of a wet air cleaner in the livestock house.

Hyperbranched poly(benzimidazole-co-benzene) (PBIB) with a honeycomb structure is synthesized by condensation polymerization of trimesic acid (TMA) and 3,3′-diaminobenzidine (DAB) for use as a membrane high-temperature proton-exchange membrane fuel cells (HT-PEMFCs). The hyperbranched honeycomb structure of polybenzimidazole (PBI) has been introduced to impart higher mechanical strength to doped PBI membranes. The stress at break of the phosphoric acid doped PBIB (DPBIB) membrane (29 ± 3 MPa) is comparable with that of Nafion (28 ± 2 MPa) and much superior to doped PBI membranes. The DPBIB membrane exhibits lower proton conductivity than Nafion 115. On the other hand, the proton conductivity of Nafion 115 is enhanced with increase in relative humidity, whereas humidity has only a moderate effect on the proton conductivity of the DPBIB membrane. Consequently, the Nafion 115 membrane in a fuel cell cannot operate in the absence of humidity, whereas the DPBIB membrane can perform well. The power output of the DPBIB membrane in a fuel cell is superior under humid conditions than under dry conditions. The maximum power output from the DPBIB and Nafion 115 membranes is comparable under humid conditions. It is concluded that the DPBIB membrane, but not Nafion, is suitable for application in HT-PEMFCs.