Search

Copyright of Steel Pipe is the property of Steel Pipe Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study seeks to discover the change of cloud's expansion rate with self-designed shock wave dispersion system. Transmission, diffraction and reflection could be observed intuitively when shock waves passed through solid particle layers. Results show that the longitudinal motion of particle group greatly influenced cloud's volume growth, thus, the maximum rate of longitudinal expansion of clouds was almost twice that of lateral expansion. The cloud growth rate and volume acceleration increased with smaller particle size, thicker particle layer and stronger shock wave intensity. Also, the expansion rate initially had a drastic decrease, small particles made clouds volume acceleration unstable and experienced a subsequent swift rise. Shock wave intensity influenced diffraction and reflection formation waves as well as the cloud's shape and expansion rate. This study therefore proposed a controlling model for cloud's expansion rate, which could illustrate differences between acceleration stage of dynamic action and deceleration stage of resistance action. Unlabelled Image • The leading factor of cloud volume growth is longitudinal motion of particle group. • The maximum vertical expansion rate of cloud is almost twice that of the lateral. • Small particles make clouds growth acceleration unstable and rise suddenly. • Shock wave strength affects diffracted and back wave formation, then clouds shape. • A controlling mechanism for cloud cluster expansion rate is proposed. [ABSTRACT FROM AUTHOR]

Purpose: Liver transplantation is a curative treatment option for hepatocellular carcinoma. In this review, we aimed to review liver transplantation criteria for hepatocellular carcinoma and patient survivals. Methods: We reviewed literature in terms of liver transplant criteria for hepatocellular carcinoma. Patient eligibility criteria, post-transplant survivals, tumor recurrence and expansion of Milan criteria rates were analyzed. Results: The Milan criteria, after being published in 1996, have become for deceased donor liver transplantation in hepatocellular carcinoma worldwide. Later, many transplant centers published their own liver transplant criteria. Most of the criteria consisted of morphological tumor characteristics based on tumor size and number. The newest published one is Malatya criteria. The 5-year overall survival according the all of the criteria is greater than 50%. There were just one paper which compare criteria according to survival and Malatya criteria were the best amongst extended criteria with 5-year OS 79.7% in that study. Conclusion: It is clear that morphological criteria consisting only of tumor size and number are insufficient in patient selection for liver transplantation and should thus be combined with biological, inflammatory, radiological, pathological and genetic markers that predict the biological behavior of the tumor. Efforts to find the best criteria are still ongoing and 5-year overall survival should be greater than 60%. [ABSTRACT FROM AUTHOR]

Meshed skin grafting is a common technique in operations to minimize surgery on the donor site area. However, the donor site area is empirically determined by surgeons due to the lack of a reliable formula to calculate the donor area required to cover a skin defect. To determine the minimal size for donor skin, the expansion rates of 1.5:1, 3:1, and 6:1 meshed skin graft and the area actually covered by them were investigated in real‐world operations. About 51 patients who received 57 operations with meshed skin grafts were enrolled in this study. The average clinical coverage rates of area in cases in which 1.5:1, 3:1, or 6:1 meshed skin grafting was performed were 1.02, 1.29, or 2.18, respectively. Those rates were notably low when recipient sites were concave. The average expansion rates of 1.5:1, 3:1, and 6:1 meshed skin grafts were about 1.16, 1.61, and 2.32, respectively. These results indicate that the size of donor skin should be about 85%, 60%, and 45% size of the recipient site to achieve the target 1.5:1, 3:1, and 6:1 meshed skin graft, respectively. In addition, the donor area should be adjusted in consideration of the shape of the recipient sites. [ABSTRACT FROM AUTHOR]

The mechanical behaviors of the self‐stressing steel slag aggregate concrete filled steel tubular (SSSACFST) stub column are investigated for practical structural applications. Twelve specimens under axial and eccentric compression are tested. The influences of different parameters, such as the eccentricity, the diameter–thickness ratio of the steel tube and the expansion rate of the steel slag aggregate concrete (SSAC) are studied. The experimental results show that the shear and the bending deformation dominate the failures of the specimens under axial and eccentric compression, respectively. The column with a high diameter–thickness ratio has a low ultimate bearing capacity and ultimate strain. The incremental range of the load capacity and the ultimate axial and circumferential strains of the specimens will be increased by raising the expansion rate of the SSAC. Based on the experimental results, the applicability of the current concrete filled steel tube design provisions for the SSSACFST stub columns is evaluated, and two analytical models for predicting the bearing capacity of the SSSACSFT stub columns under axial and eccentric compression are proposed. [ABSTRACT FROM AUTHOR]

We characterize geometrically the Lyapunov exponents of a cocycle (of arbitrary rank) with respect to a harmonic current defined on a hyperbolic Riemann surface lamination. Our characterizations are formulated in terms of the expansion rates of the cocycle along geodesic rays. [ABSTRACT FROM AUTHOR]

Monitoring foam expansion and the study of foaming kinetics during in-situ foam filling are essential to ensure a desirable quality of foam-filled profiles. In this current research, a novel technique is proposed for monitoring in-situ aluminum foam filling of hollow profiles. In this technique, instantaneous temperatures measured at various locations of the hollow profile being filled have been used to determine the foam expansion rate. Hence, the apparatus developed in this study is named as thermal expandometer. To demonstrate the usefulness of this thermal expandometer, aluminum foaming is performed inside a steel tube by heating the foaming precursor at different rates, and an analysis of the effect of heating rate on the foam expansion rate is presented. [ABSTRACT FROM AUTHOR]

Copyright of Mountain Research (10082786) is the property of Mountain Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biological invasion poses a huge threat to ecological security. Spartina alterniflora was introduced into China in 1979, and its arrival corresponded with negative effects on native ecosystems. To explore geographical variation of its expansion rate in coastal China, we selected 43 S. alterniflora sites from Tianjin Coastal New Area to Beihai. The area expansion rate, expansion rate paralleling and vertical to the shoreline were analysed based on Landsat images and field survey in 2015. Simple Ocean Data Assimilation (SODA) and climate data were collected to statistically analyse the influential factors of expansion rate. Results showed that significant difference of S. alterniflora area expansion rate among different latitude zones (P < 0.01), increasing from 6.08% at southern (21°N–23°N) to 19.87% in Bohai Bay (37°N–39°N) along latitude gradient. There was a significant difference in expansion rate vertical to shoreline in different latitude zones (P < 0.01) with the largest occurring in Bohai Bay (256 m/yr, 37°N–39°N), and showed an decreasing tendency gradually from north to south. No significant difference and latitudinal clines in expansion rate paralleling to shoreline were observed. Expansion rate had significant negative correlation with mean seawater temperature, the lowest seawater temperature, current zonal velocity and meridional velocity and presented a reducing trend as these biotic factors increased; however, they were not significantly correlated with the highest seawater temperature and mean seawater salinity. We identified significant correlations between expansion rate and annual mean temperature, the lowest temperature in January and annual precipitation, but there was little correlation with annual diurnal difference in temperature and the highest temperature in July. The rapid expansion rate in high-latitude China demonstrated a higher risk of potential invasion in the north; dynamic monitoring and control management should be established as soon as possible. [ABSTRACT FROM AUTHOR]

Biofilms are communities of tightly associated bacteria encased in an extracellular matrix and attached to surfaces of various objects, such as liquid or solid surfaces. Here we use the multi‐channel wide field stereo fluorescence microscope to characterize growth of the Bacillus subtilis biofilm, in which the bacterial strain was triple fluorescence labeled for three main phenotypes: motile, matrix producing and sporulating cells. We used the feature point matching approach analyzing time lapse experimental movies to study the biofilm expansion rate. We found that the matrix producing cells dominate the biofilm expansion, at the biofilm edge, the expansion rate of matrix producing cells was almost the same as the velocity of the whole biofilm; however, the motile and sporulating cells were nearly rest. We also found that the biofilm expansion rate evolution relates to cell differentiation and biofilm morphology, and other micro‐environments can influence the biofilm growth, such as nutrient, substrate hardness and colony competition. From our work, we get a deeper understanding of the biofilm growth, which can help us to control and to further disperse the biofilm. [ABSTRACT FROM AUTHOR]

• The entropy generation is introduced as a criterion to analyze the impact of expansion rate in a wet-steam flow. • The simulation of wet-steam flow in turbine cascades is performed using NURBS-based meshing technique. • The results show a significant improvement compared to those obtained by the typical H-type grid. • Impacts of the expansion rate on the condensation phenomenon are investigated. In this paper, the entropy generation is introduced as a criterion to analyze the impact of variation of expansion rate in a two-dimensional viscous wet-steam flow through stationary cascades of a steam turbine. In addition, for the first time the NURBS-based mesh generation method is introduced and assessed in the field of wet-steam flow. In the mentioned method, the computational grid with "curved" boundaries is generated by non-uniform rational B-spline (NURBS) surface that describes the geometry of the cascade. The results, which are validated against well-established experiments, reveal that compared to the typical H-type grid, employing the generated NURBS-based mesh significantly reduce the computational error of numerical simulation. According to the obtained results, the prediction errors of static pressure distribution and droplet average radius are reduced by 31% and 78.44%, respectively. Furthermore, it is observed that decreasing the expansion results in moving the nucleation zone toward downstream of the blade and increasing the rate of droplets nucleation. Additionally, the liquid mass fraction as well as the amount of entropy and total entropy generation in the fluid flow increases. [ABSTRACT FROM AUTHOR]

Abstract One of the best ways to increase the fiber content in the diet is supplementing wheat bran in bread. Wheat bran is known to affect the cellular structure of the dough, resulting in lower final bread volume. The present study was focused on analyzing the effect of wheat bran in throughout the bread making process; the results were compared with the recipe without bran. Wheat bran at different level viz., 0%, 8%, 16% and 24% w/w on flour basis was added into the wheat flour for the preparation of sandwich bread. Results showed that wheat bran significantly (p < 0.05) affected the dough kneading parameters. Dough properties like stickiness and extensibility decreased with respect to increase in bran quantity. Unexpectedly, wheat bran enhanced the aeration of dough during mixing and the expansion rate of dough during fermentation. However, wheat bran decreased the specific volume of bread upto 10.81%, which was confirmed using 2D image analysis method where it was observed as the wheat bran alters the pore size distribution in bread crumb. Highlights • Wheat bran improves the fiber content of the sandwich bread and affects dough and bread properties. • Effect of wheat bran on carbon dioxide release was studied by measuring expansion rate of dough during fermentation. • Dough rheological properties with and without addition of bran were studied to quantify its effect on dough. • Wheat bran at higher level significantly increased the dough development time and porosity. • Image analysis was carried out to find the effect of bran on pore area distribution in bread crumb. [ABSTRACT FROM AUTHOR]

The influence of admixture water retention agent and plastic expansive agent on performance of grouting agent were studied. The results shows that admixture provides fluidity for grouting materials there is a big difference in different cement the higher cement specific surface area and water requirement of normal consistency the larger admixture dosage rang and the lower admixture sensitivity. Starch ether can effectively improve the stability of grouting and the amount is between 0.10% and 0.17% the stability of grouting is good. The mass percentage of plastic expansive agent between 0.33% and 0.67% can provide slight expansion in grouting materials. [ABSTRACT FROM AUTHOR]

The American mink, an invasive mammal introduced to Europe, severely impacts native biodiversity. The history of its invasion has been poorly investigated in central and eastern Europe, and the current variations in densities of mink populations are not well studied, thus making a reduction of its impact difficult. Here we analyse the temporal dynamics and spatial distribution of the American mink population in Poland, which began to establish itself at the beginning of the 1980s and originated from Polish farm escapees and immigrants from Lithuania and Belarus. Mink dispersal started in the north and continued to the south and in 2016 mink occurrence was recorded across ca. 75% of the country. By about 1997 mink had colonised half of Poland, and in 2016 the only mink-free area was in the south and south-east of the country. The rate of expansion showed accelerating and decelerating patterns, and reached its maximum 12 years after the beginning of the expansion. Mink farming in western Poland developed rapidly after 2000 and probably influenced acceleration of mink range expansion rates in years 2006-2008. Indices of mink densities showed significant nonlinear change over time since local populations were established and were highest in populations estimated to be 10-15 years old. The prediction of non-native species invasion rates and population dynamics should be incorporated into management actions curbing their negative impact on native fauna. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas & Oil is the property of Editorial Department of Natural Gas & Oil and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of compressive strength and expansion rate of filler grout on bond behavior of grouted pipe splice is discussed. Three types of grout were designed and utilized to prepare coupler specimens as filler material. The compressive strength ranged from 67.5 to 91.8 MPa. The volume expansion rate changed from -0.023% to -0.037% under airtight curing condition, and from 0.027% to 0.057% under water curing condition, respectively. Based on pullout test, it was found that the bond strength and stiffness of grouted splice both improve with the increment of the expansion rate due to the increased initial confinement. By experimentally measuring the exterior surface transverse strain of grouted sleeve in curing stage, the confinement and its influencing factor on bond performance were derived. The confinement increases nonlinearly with the increment of grout shell thickness and sleeve radial stiffness other than grout expansion rate. The diameter-thickness ratio of sleeve should not exceed 13 to avoid a possible debonding failure at bar-grout interface. Utilizing the calculated confining pressures, the bond strength of the grouted splice was determined and compared with pullout test result, which shows a good agreement. [ABSTRACT FROM AUTHOR]

The foamed asphalt was produced by selfdeveloped foaming machine. The effects of asphalt types, heating temperature, foaming water content and pressure (air pressure and water pressure) on the performance of asphalt foaming were investigated through orthogonal test, and the foaming factors and the foaming process were analyzed. The results show that proper asphalt temperature can improve the asphalt fluidity to enlarge the expansion rate of foamed asphalt. It is not appropriate to increase water consumption only for enlarging expansion rate, and excessive water consumption can inhibit the growth of asphalt foam, especially for modified asphalt. The effect of pressure on foaming properties of matrix asphalt is opposite to that of modified asphalt. The foaming performance of matrix asphalt and modified asphalt should be treated separately, and on the basis of modified asphalt, the expansion rate and the half-time of matrix asphalt from Panjin Liaoning should be increased by 25% and 30%, respectively. [ABSTRACT FROM AUTHOR]

To identify cost-effective ways to control invasive species, we need to evaluate alternative methods. The invasion of tropical Australia by cane toads (Rhinella marina) has killed many native predators, prompting efforts to cull adult toads. We analyzed a dataset on > 17,500 toads killed by government-employed teams from 2005 to 2008, using a range of methods (incidental captures, targeted searches, traps) as well as records of toads found as road kills. The culling occurred in the northwestern part of the Northern Territory, moving west as the toad front expanded into Western Australia. Both season and method affected rates of capture and demographic attributes (sex ratio, proportion of adults) of the culled anurans, with a strong interaction between these factors. Most methods were more effective during and after the seasonal monsoons (when moist conditions facilitated anuran activity), but that seasonal variation was greater for numbers of toads found on the roads than captured in other ways. Juvenile toads and adult female toads constituted higher proportions of total captures in the Early Dry than in other times of year, reflecting seasonal breeding. Traps caught a higher proportion of adult female toads than did other methods, but overall had low capture rates. Rates of range expansion by toads were similar before, during and after the culling effort, suggesting that removing adult toads did not affect the speed of the invasion. Nonetheless, culling adult cane toads may be effective in some situations (“island” populations, extralimital translocations), and results from this program may be valuable for future toad-control efforts. [ABSTRACT FROM AUTHOR]

• Effects of water-cement ratios on the ASR of SWSSC were investigated. • Pore structure and Na+ consumption are two dominant factors influencing ASR of SWSSC. • The worst water-cement ratio of SWSSC for the highest expansion rate is 0.45. • Magnesium element mainly coexists in Na-shlykovite and transition zone in SWSSC with W/C = 0.55. Research of seawater and sea sand concrete (SWSSC) is the current hot topic, but effects of water-cement ratios (W/C) on alkali-silica reaction (ASR) of SWSSC haven't been investigated. To solve this issue, the ASR products, pore structure and expansion rate of specimens with different W/C (0.35 ∼ 0.55) were measured. The study shows that pore structure and Na+ consumption are two key factors influencing ASR of SWSSC. When the W/C increases from 0.45 to 0.55, Na+ in specimen replaces K+ in ASR-P1(K 0.52 Ca 1.16 Si 4 O 8 (OH) 2.84 ·1.5H 2 O), and ASR-P1 is converted into Na-shlykovite(NaCaSi 4 O 8 (OH) 3 ·2.3H 2 O); the porosity is the dominant factor for the expansion rate of SWSSC. When the W/C increases from 0.35 to 0.45, the Na+ consumption is the dominant factor for the expansion rate of SWSSC. Magnesium element mainly coexists in Na-shlykovite and transition zone in SWSSC with W/C = 0.55. The research results are beneficial to inhibit ASR of SWSSC with different W/C and improve their durability. [ABSTRACT FROM AUTHOR]

The overall and integrated development of the country, in a way which covers all people and groups and also all its places, needs a balanced spatial structure and settlement system. Access to such balanced situation needs the strengthening and development of small and medium cities in Iran provinces. Therefore the main question of this research is that "How much is the development rate of small and medium cities of Iran's provinces in year 2006"? To answer this question, after reviewing the theoretical bases, the evaluation variables were determined and the research hypothesis was offered based on more development of small and medium cities in the northern and western provinces of Iran". For evaluating and testing the research hypothesis, in the frame work of analytical-descriptive method, the overall index of "development rate of small and medium cities" was operated and measurable by six main indicators and based on simple weighting method. The required data were gathered by library method. The weights of indicators were obtained by AHP group method. Data analysis and hypothesis test was made by descriptive statistical methods and also independent t-test. The results showed that expansion rate in small and medium cities in different provinces is various. The significant difference between the northern and western provinces with the provinces of southern and eastern ones was approved. The results showed a relation between the expansion rate of such cities with the natural environment and also the regional and national pattern of expansion.